Canadian Standards Association

Transcription

1 S6S Laterally supported members When continuous lateral support is provided to the compression flange of a member subjected to bending about its major axis, the factored moment resistance, M r, shall be calculated as M r = s Z x F y = s M px Laterally unbraced members For a section subjected to bending about its major axis and laterally unbraced over a length, L, the factored moment resistance, M r, shall be calculated as Mp (a) Mr = 115 smp f smp Mu Mp ; or M f, when > 067. u (b) M r = s M u, when M u 0.67M p The critical elastic moment, M u, of a monosymmetric section shall be taken as w Mu = 2 π EIGJ 2 s y s B + + B + B L where 4M max w 2 = Mmax + 4Ma + 7Mb + 4Mc 25. where M max = maximum factored bending moment magnitude in unbraced segment, N mm M a = factored bending moment at one-quarter point of unbraced segment, N mm M b = factored bending moment at midpoint of unbraced segment, N mm M c = factored bending moment at three-quarter point of unbraced segment, N mm L = length of unbraced segment of beam, mm B 1 = π b EI x sy 2L GJ s where x = coefficient of monosymmetry B 2 = π 2 EC s w 2 LGJ s For doubly symmetric sections, x = 0.0 B 1 = 0.0 so that π E M u = s EIGJ sy s + p lc y w L L The general expression for the critical elastic moment and formulas for x, J, and C w for I-girder and open-top box girders as specified in Clause C of CSA S6.1 may be used for guidance. A more rigorous analysis, taking into account both elastic and inelastic behaviour, may also be used. w Bending about the minor axis For a section subjected to bending about its minor axis, whether laterally braced or unbraced, the factored moment resistance, M r, shall be calculated as M r = s Z y F y = s M py 456 (Replaces p. 456, November 2006)

2 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Longitudinal stiffeners shall be proportioned so that (a) the stiffener width-to-thickness ratio does not exceed 200/ unless the section properties are deemed to be based on an effective width of 200/ ; (b) the projecting stiffener width is less than or equal to 30t ; (c) I hw 3 (2.4(a/h) ); and F y (d) r a 1900 where I and r are calculated about a centroidal axis parallel to the web for a section comprising the stiffener or stiffeners and a strip of web 10w wide on each side Transverse stiffener requirements for longitudinally stiffened webs Transverse stiffeners for girder panels with longitudinal stiffeners shall meet the requirements of Clause In addition, the section modulus of the transverse stiffener, where I is calculated with respect to the base of the stiffener, shall not be less than S t = hs h / 3a. When j is calculated for the purpose of calculating the required moment of inertia, I, of the transverse stiffener in accordance with Clause (a), the depth of subpanel, h p, shall be used for calculating h/a. When Clause (b) is applied to longitudinally stiffened girders, the depth of subpanel, h p, shall be used for calculating a/h in the equation for A s ; the full depth of the web, h, shall be used for calculating C and V r. F y F y Bearing stiffeners Web crippling and yielding Bearing stiffeners shall be provided where the factored concentrated loads or reactions at the ULS exceed the factored compressive resistance of the webs of beams or girders. The factored compressive resistance of the web, B r, shall be calculated as follows: (a) for concentrated loads applied at a distance from the member end greater than the member depth, the lesser of (i) B r = bi w (N + 10t )F y (b) 2 (ii) B r = 145. f bi w where F y E s bi = 0.80 N = length of bearing, mm t = flange thickness, mm for end reactions, the lesser of (i) B r = be w (N + 4t )F y (ii) 2 B r = 060. f be w F y E s where be = 0.75 N = length of bearing, mm t = flange thickness, mm (Replaces p. 461, November 2006) 461

3 S6S Bearing resistance and details Bearing stiffeners shall extend the full depth of the web and shall be fitted to bear against the flange through which the loads are transmitted or be connected to the flange by welds. Stiffeners shall preferably be symmetrical about the web and extend as close to the edge of the flanges as practicable. The width-to-thickness ratio of bearing stiffeners shall not exceed 200/ F y. The factored bearing resistance of the bearing stiffeners, B r, shall be calculated as B r = 1.50 s A s F y where A s = area of stiffener in contact with the flange, mm 2 F y = yield stress of the stiffener or flange, MPa, whichever is less Compressive resistance Bearing stiffeners shall be designed as compression members in accordance with Clause 10.9, assuming a column section comprising all of the projecting stiffener element plus a strip of web extending not more than 12w on both sides of each stiffener element. The effective column length shall be taken as not less than 0.75 times the depth of the girder. Connections shall be designed for the interface force transmitted from the web to the stiffeners Lateral bracing, cross-frames, and diaphragms Intermediate cross-frames or diaphragms The spacing of intermediate cross-frames or diaphragms shall be determined from an investigation of the lateral torsional buckling resistance of the longitudinal girders, the need to transfer lateral wind forces, and the need to provide torsional restraint to the girders for any anticipated applied torsional loading. Cross-frames and diaphragms shall be designed for the lateral loads they are required to resist plus a lateral load equivalent to 1% of the compression flange force in the beam or girder at the location under consideration. If the intermediate cross-frames or diaphragms are included in the structural model used to determine the forces in the girders, they shall be designed for the forces that they attract. Intermediate cross-frames shall be placed normal to the main members when the supports are skewed more than 20 and shall be designed for the forces they attract. Where girders support deck slabs proportioned in accordance with the empirical design method of Clause , the spacing of intermediate cross-frames, ties, or diaphragms shall satisfy the requirements of Clause Lateral Bracing If lateral loads are not resisted by the girders alone, a lateral bracing system shall be provided at or close to either the top or bottom flanges. Bracing systems shall be designed to resist a lateral load equivalent to at least 1% of the compression flange force in the beam or girder at the location under consideration, in addition to other applied forces for the limit state under consideration. The bracing system shall have sufficient stiffness to maintain the stability of the braced flange when the system has displaced, at the location under consideration, through the distance required to develop the bracing resistance. A steel or concrete deck used for this function shall be rigidly connected to the compression flange. Timber floors shall not be considered to provide adequate lateral support unless the floor and fastenings are designed for this purpose. Unless otherwise justified by analysis, girder spans longer than 50 m shall have a system of lateral bracing at or close to the bottom flange. As required by Clause A5.1.6, lateral bracing systems shall be designed for the forces they attract in maintaining the compatibility of deformations of girders under vertical loading. 462 (Replaces p. 462, November 2006)

4 t c d y t y b Centre of gravity of steel section b e A r A s f s F y (a) Plastic neutral axis in the concrete slab a Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Compression zone f r f y 0.85f c f c T s C c C r e c e r d s b e 0.85f c f c f r f y d s Plastic neutral axis of composite section A r t c C c C r y tc y bc d A s h t t y t f s F y T s C s es e c e r t b y b f s F y (b) Plastic neutral axis in the steel section Figure 10.1 Class 1 and 2 sections in positive moment regions (See Clauses , , and ) Plastic neutral axis in concrete When C 1 is greater than C 2, the plastic neutral axis is in the concrete slab as shown in Figure 10.1(a), and the depth of the compressive stress block, a, shall be calculated as C2 frarfy a = 085. f bf c e c The factored moment resistance, M r, of the section shall be calculated as M r = C c e c + C r e r where C c = 0.85 c b e a f c (Replaces p. 465, November 2006) 465

5 S6S Plastic neutral axis in steel When C 1 is less than C 2, the plastic neutral axis is in the web as shown in Figure 10.1(b), and the depth of the compressive stress block, a, shall be taken as equal to t c. The factored moment resistance, M r, shall be calculated as M r = C c e c + C r e r + C s e s where C c = 0.85 c b e t c f c C s = 0.5( s A s F y C 1 ) Negative moment regions Moment resistance of composite section When (a) shear connectors are provided; and (b) slab reinforcement is continuous over interior supports or the slab is prestressed longitudinally, the factored moment resistance, M r, of the section shall be calculated on the basis of a fully plastic stress distribution in the structural steel, reinforcement, and prestressing strands, as shown in Figure 10.2, as follows: M r = T r e r + T s e s where T r = r A r f y T s = 0.5( s A s F y T r ) The requirements of Clause shall also be satisfied. When shear connectors are not provided in the negative moment regions, the factored moment resistance shall be taken as that of the steel section alone, calculated in accordance with Clause b e A r T r f r f y t c y t Neutral axis T s e r d A s f s F y C s y b e s f s F y Figure 10.2 Class 1 and 2 sections in negative moment regions (See Clause ) 466 (Replaces p. 466, November 2006)

6 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Longitudinal reinforcement in non-prestressed slabs When the longitudinal tensile stress in non-prestressed deck slabs at SLS exceeds c f cr, the longitudinal reinforcement, including longitudinal distribution reinforcement, shall not be less than 1% of the cross-sectional area of the slab. At least two-thirds of this reinforcement shall be placed in the top layer of the slab reinforcement and within the effective width of the slab Negative moment regions without shear connectors When shear connectors are not provided in the negative moment region, the longitudinal reinforcement shall be extended into the positive moment regions in accordance with Clause 8.15, and additional shear connectors shall be provided in accordance with Clause Class 3 sections Width-to-thickness ratios The portions of the steel section in compression shall comply with Clause Positive moment regions Moment resistance For composite sections in which the depth of the compression portion of the web of the steel section, calculated on the basis of a fully plastic stress distribution, equals or is less than 850w/ F y, the factored moment resistance shall be determined in accordance with Clause Moment resistance of slender members When the depth of the compression portion of the web of the steel section, calculated in accordance with Clause , exceeds 850w/ F y, the factored moment resistance, M r, of the composite section shall be calculated on the basis of fully plastic stress blocks, as shown in Figure 10.3, as follows: M r = C c e c + C r e r + C s e s where C c = 0.85 c b e t c f c C r = r A r f y C s = s A sc F y The area of the steel section in compression, A sc, shall include the top flange and a web area of (850w 2 )/ F y, and the area of the steel section in tension, A st, shall be calculated as follows: C + C + C Ast = F c r s f s y (Replaces p. 467, November 2006) 467

7 S6S1-10 t c d b e A r w A s 850 w/ F y t t 0.85f c f c y t f s F y f r f y C r C c C s e e r c e s T s y b Figure 10.3 Class 3 Sections in positive moment regions (See Clause ) Negative moment regions Composite sections When (a) shear connectors are provided; and (b) slab reinforcement is continuous over interior supports or the slab is prestressed longitudinally, the factored moment resistance of the composite section shall be taken as the resultant moment based on the linear stress distribution at first yielding or buckling, as shown in Figure 10.4, and the requirements specified in Clause shall be satisfied The following requirements shall be satisfied: (a) M fd /S + (M fsd + M fl )/S s F cr where S and S are the elastic section moduli with respect to the bottom fibre, F cr = M r / s S, and M r is determined in accordance with Clause , based on the steel section. (b) M fd /S + (M fsd + M fl )/S s F y where S and S are the elastic section moduli with respect to the top fibre of the steel section. (c) (M fsd + M fl )/S r f y where S is the elastic section modulus with respect to the centroid of the top layer of longitudinal slab reinforcement. The applicable requirements of Clauses and shall also be satisfied. 468 (Replaces p. 468, November 2006)

8 M fd S Dead load on bare steel girder f r f y + = M fsd + M fl S Superimposed dead plus live load on composite girder Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code < f s F cr f s F y Total accumulated stresses Figure 10.4 Class 3 Sections in negative moment regions (See Clause ) Non-composite sections When shear connectors are not provided in the negative moment regions, the factored moment resistance shall be taken as that of the steel section alone, calculated in accordance with Clause The requirements of Clause shall also be satisfied Stiffened plate girders Width-to-thickness ratios Stiffened plate girders shall meet the requirements of Clauses and Positive moment regions Moment resistance For composite sections in which the depth of the compression portion of the web of the steel section, calculated on the basis of a fully plastic stress distribution, does not exceed 850w/ F y, the factored moment resistance shall be determined in accordance with Clause Moment resistance of slender webs When the depth of the compression portion of the web of the steel section calculated in accordance with Clause exceeds 850w/ F y, whether or not longitudinal stiffeners are provided, the factored moment resistance of the composite section shall be calculated on the basis of fully plastic stress blocks, as in Clause (Replaces p. 469, November 2006) 469

9 S6S Negative moment regions Composite sections When (a) shear connectors are provided; and (b) slab reinforcement is continuous over interior supports or the slab is prestressed longitudinally, the factored moment resistance of the section shall be calculated in accordance with Clause If longitudinal stiffeners are not provided and 2d c /w > 1900 F y, the factored moment resistance shall be reduced by the factor specified in Clause Non-composite sections When shear connectors are not provided in the negative moment region, the factored moment resistance shall be taken as that of the steel section alone (see Clause ). The requirements of Clause shall also apply Shear connectors General Shear connectors shall comply with the applicable materials specification of Clause 10.4 and shall be capable of resisting both horizontal and vertical movements between the concrete slab and the steel beam or girder. The fatigue resistance of the base metal at the connection weld of shear connectors shall meet the requirements of Clause The fatigue resistance of stud shear connectors shall meet the requirements of Clause Cover and edge distances The clear depth of concrete cover over the top of shear connectors shall meet the requirements of Clause Shear connectors shall extend into the concrete deck so that the clear distance from the underside of the head of the shear connector to the top of the bottom transverse reinforcement or, when the slab is haunched, to the top of the transverse reinforcement in the slab haunch, is at least 25 mm. The clear distance between the edge of a girder flange and a shear connector shank shall be at least 25 mm Resistance, placement, and spacing In determining the resistance of shear connectors, connector strength and spacing, concrete strength and, where stud connectors are embedded in grout, grout strength, including grout side cover to the studs, shall be taken into consideration. Use of connectors that are fastened to the steel section by means other than welding shall require Approval. The minimum number of shear connectors in each shear span shall be calculated as follows: N = P/q r where a shear span is a segment between points of maximum and zero moment at the ULS and P is determined as follows: (a) for positive moment: (i) when the plastic neutral axis is in the concrete slab: P = s A s F y ; and (ii) when the plastic neutral axis is in the steel section: P = 0.85 c f c b e t c + r A r f y ; and (b) for negative moment: P = r A r f y. The factored shear connector resistance, q r, shall be determined in accordance with Clauses to Stud connectors in cast-in-place deck slab The factored shear resistance, q r, of a headed stud shear connector with h/d 4 shall be taken as q = 05. f A f E f F A r sc sc c c sc u sc 470 (Replaces p. 470, November 2006)

10 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code where F u = minimum tensile strength of the stud steel (450 MPa for CSA W59 Type B studs) A sc = cross-sectional area of one stud shear connector, mm 2 The spacing of shear connectors shall not be less than 4d, nor greater than 600 mm. Stud connectors shall be spaced uniformly in a shear span or spaced according to the variation in the interface shear Stud connectors in full-depth precast panels This Clause applies to full-depth precast panels where grout pockets (blockouts) are provided to accommodate clusters of stud connectors welded to the steel section. The pockets are filled with non-shrink grout to provide composite action. The grout pockets shall be shaped to prevent vertical separation between the deck slab and the steel section unless other means of interlocking are provided. The concrete used in the precast panels shall have f c 35 MPa and the compressive strength of the grout shall be equal to or greater than the f c of the concrete. The precast panels shall meet all the requirements of Section 8. Local effects due to the actions of the studs shall also be considered. Post-tensioning, when specified, shall precede the grout placement. The maximum spacing of stud clusters shall not exceed 1200 mm. The minimum spacing of studs within the pocket shall be 4d. The grout side cover, taken as the shortest distance from the grout pocket perimeter to the shank of the nearest stud, shall be greater than or equal to 1.5d. The factored resistance of a stud shear connector, q r, shall be determined in accordance with Clause In this calculation, the values for f c and E c shall be based on the compressive strength of the grout. The grout strength shall not be greater than 1.3 times the f c of the precast concrete. Where the stud cluster spacing exceeds 600 mm, the minimum number of studs per cluster shall vary according to the variation in the interface shear. The use of stud connectors 25 mm in diameter or larger shall require Approval Channel connectors in cast-in-place deck slab In solid slabs of normal-density concrete, the factored shear resistance for channel shear connectors shall be taken as ( ) q = 45f t w L f r sc c c where t = average thickness of channel shear connector flange, mm w = thickness of channel shear connector web, mm L c = length of channel shear connector, mm Channel connectors shall be spaced according to the variation in the interface shear Longitudinal shear The longitudinal factored shear resistance along any potential shear planes shall be greater than the factored longitudinal shear. The factored longitudinal shear in the slab of a composite beam, V u, shall be taken as V = Sq 085. f A f f A f u r c c c r rl y For normal-weight concrete, the factored shear resistance along any potential shear surface in the concrete slab shall be calculated as V = 080. f A f f A 050. f A f r r rt y c cv c cv c For lightweight concrete, the constant 2.76 with units of MPa shall be replaced by (Replaces p. 471, November 2006) 471

11 S6S Lateral bracing, cross-frames, and diaphragms The requirements of Clause shall be met Composite box girders General Clause applies to the design of simple and continuous composite box girder bridges of spans up to 110 m, consisting of one or more straight steel single-cell box girders, acting compositely with a concrete deck, and symmetrical about a vertical axis. For longer spans, other requirements may apply. The top of the box may be open with twin steel flanges or closed with a steel flange plate. Exterior access holes with hinged and locked doors shall be provided. Openings in box sections shall be screened to exclude animals. The requirements of Clauses to shall also apply Effective width of tension flanges The effective width of bottom flange plates in tension shall be taken as not more than one-fifth of the span for simply supported structures and not more than one-fifth of the distance between points of contraflexure under dead load for continuous structures Web plates Webs shall be proportioned in accordance with Clause and, for single box girders, in accordance with Clause The shear force to be considered on each web shall be V f /cos, where V f is one-half of the total vertical shear force at the ULS on one box girder and is the angle of inclination of the web plate to the vertical. The inclination of the web plates shall not exceed 1 horizontal to 4 vertical Flange-to-web welds The total effective throat of the flange-to-web welds shall not be less than the thickness of the web unless internal diaphragms or cross-frames are spaced in accordance with Clause and a minimum of two intermediate diaphragms per span are used inside the box. If fillet welds are used, they shall be placed on both sides of the connecting flange or web plate Moment resistance Composite and non-composite sections The factored moment resistance of the steel section acting alone before the attainment of composite action shall be determined in accordance with (a) (b) Clauses 10.10, , and for regions of positive moment; and Clauses and to for regions of negative moment, using the elastic section modulus of the steel section alone The factored moment resistance of the composite section shall be determined in accordance with (a) Clauses 10.11, , and for regions of positive moment; and (b) Clause for regions of negative moment, except that in applying Clause or , F cr shall be determined in accordance with the applicable requirements of Clauses to (Replaces p. 472, November 2006)

12 Unstiffened compression flanges Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The factored moment resistance with respect to the compression flange shall be calculated as follows: (a) when b/t 510/ : M r = s F y S (b) when 510/ < b/t 1100/ : M r = s F cr S where C = 1100 ( b/ t) 590 (c) when b/t > 1100/ F y : M r = s F cr S where F cr = ( b/ t) F y F y F cr = πc Fy sin 2 where F y F y Compression flanges stiffened longitudinally The factored moment resistance with respect to the compression flange shall be calculated as follows: (a) when bs / t 255 k 1 / Fy : M r = s F y S (b) when 255 k1/ Fy < bs / t 550 k1/ Fy : M r = s F cr S 472A

13

14 where F cr = πcs Fy sin 2 where C s = 550 k1 ( bs / t) Fy 295 k (c) when bs / t > 550 k 1 / Fy: M r = s F cr S where F cr = The buckling coefficient, k 1, in Clause shall be determined as follows: (a) For n = 1: 8Is k1 = 3 bt s (b) For n > 1: Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code 14 3Is k1 = 3 4. bt s n 40. where n = number of longitudinal stiffeners I s = moment of inertia of each stiffener about an axis parallel to the flange and at the base of the stiffener, mm The longitudinal stiffeners shall be equally spaced across the flange width. A transverse stiffener shall be placed near the point of contraflexure under dead load and shall be equal in size to a longitudinal stiffener Compression flanges stiffened longitudinally and transversely The factored moment resistance with respect to the compression flange shall be calculated as follows: (a) when bs / t 255 k 2 / Fy: M r = s F y S (b) when 255 k / F < b / t 550 k / F : M r = s F cr S 18k ( b / t) 13 / s / 2 y s 2 y 1 where F cr = πcs Fy sin 2 (Replaces p. 473, November 2006) 473

15 S6S1-10 where C s = (c) when bs / t > 550 k 2 / Fy: M r = s F cr S where F cr = k 2 = k ( b / t) s 4 k ( b / t) F [ 1+ ( a/ b) ] ( n+ 1) ( a/ b) [ ( n+ 1)] s k 2 y The longitudinal stiffeners shall be equally spaced across the flange width and shall be proportioned so that the moment of inertia of each stiffener, I s, about a transverse axis at the base of the stiffener is at least equal to I s = 8t 3 b s The transverse stiffeners shall be proportioned so that the moment of inertia of each stiffener, I t, about a longitudinal axis through its centroid is at least equal to I n b F cr A f t = 055. ( + 1) 3 s 3 Ea s The ratio a/b shall not exceed 3.0. The maximum value of the buckling coefficient k 2 shall be 4.0. When k 2 has its maximum value, the transverse stiffeners shall have a spacing, a, equal to or less than 4b s. The transverse stiffeners need not be connected to the flange plate but shall be connected to the webs of the box and to each longitudinal stiffener. The connection to the web shall be proportioned for a vertical force, R w, of sfs y t Rw = f 2b The connection to each longitudinal stiffener shall be proportioned for a vertical force, R s, of R s FS = f s y t nb Diaphragms, cross-frames, and lateral bracing Diaphragms and cross-frames within girders Internal diaphragms, cross-frames, or other means shall be provided at each support to resist transverse rotation, displacement, and distortion and to transfer vertical, transverse, and torsional loads to the bearings. The effect of access holes shall be considered and adequate reinforcement provided if necessary. Intermediate internal diaphragms or cross-frames shall be used to control deformation, torsional warping, and distortion of open box girders during fabrication, transportation, erection, and placement of the deck. Cross-frames, diaphragms, or cross-ties between top flanges shall be used in open trapezoidal box girders to resist the transverse resultant induced by the sloping web force opposing the vertical loads acting on the top flanges during construction. 474 (Replaces p. 474, November 2006)

16 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Super-elevation and centrifugal forces The super-elevation of the deck shall be considered when the wheel loads due to the combined effects of the centrifugal forces and the vertical live loads are being determined Thermal forces Tangential and radial movements, potential uplift at the bearings, and induced restraining forces due to the temperature changes and gradients shall be taken into account Uplift The structure shall be assessed for uplift at the supports. The assessment for dead loads shall take into account the intended sequence of construction Design theory General The whole structure shall be modelled in the analysis, including the transverse members. The analysis shall include, in addition to the torsional shear stresses, an evaluation of the longitudinal stresses due to restrained warping of members with non-uniform torsion Limiting curvature Provided that the conditions of Clause A are met, the bridge shall be considered straight for the purposes of structural analysis Bearings Bearings shall be designed to resist the vertical loads (including uplift) and the horizontal loads to which they could be subjected (including centrifugal force effects) and be designed and oriented to permit thermal movement consistent with the design assumptions Diaphragms, cross-frames, and lateral bracing Unless otherwise Approved, longitudinal girders shall be connected at each support by diaphragms designed to prevent twisting of the girders. Diaphragms or cross-frames shall be provided between I-girders, i.e., at intervals between supports, to further facilitate resistance to twisting of the girders. Each line of diaphragms or cross-frames shall extend continuously across the full width of the bridge. Diaphragms or cross-frames shall be provided between box girders where needed to augment the resistance of the girders to torsion. Diaphragms or cross-frames shall be provided inside the girders in line with those provided between the girders. Diaphragms and cross-frames shall be treated as main structural members. They shall be approximately as deep as the girders they connect and shall be connected to the girders to transfer all of the loads that they attract. In addition to the diaphragms or cross-frames used to control torsion, other cross-frames shall be provided in box girders, if necessary, to resist the distortional effects of eccentric loads on the cross-section. The need for lateral bracing between the top flanges of curved box girders and between I-girders to ensure stability and resist the effects of wind shall be assessed for all stages of construction as well as for service conditions. Where girders support deck slabs proportioned in accordance with the empirical design method of Clause , the lateral spacing of intermediate cross-frames or diaphragms shall satisfy the requirements of Clause (Replaces p. 477, November 2006) 477

17 S6S Steel I-girders Non-composite girder design Limits of applicability The following requirements shall apply: (a) The absolute value of the ratio of the torsional warping normal stress to the normal flexural stress shall, as far as possible, not exceed 0.5 at any point in the girder. (b) The unbraced length between cross-frames shall not exceed 25 times the width of the flange or 0.1 times the mean radius of the girder. (c) Flanges shall be Class 3 or better Flanges Flanges shall be proportioned to satisfy the following requirements: (a) Strength of either flange: M M fx rx Mfw + <1 M ry (b) Stability of compression flange: M fx M rx where M fx = factored bending moment due to flexure M rx M fw M ry = s F y S x where S x = elastic section modulus of the girder about its major axis = factored bending moment in the flange due to torsional warping = s F y S y where S y = elastic section modulus of the flanges only about an axis in the plane tangent to the web of the girder M rx = s F y S x (1 3 2 ) b w where = b = L b F y 2 2 π Es L L R 2b w = smaller of w1 and w2 when f w / f b is positive = w1 when f w / f b is negative 478 (Replaces p. 478, November 2006)

18 where w1 = w2 = 1 fw L 1 1 f 150 b b L b L R fw fb f w = coexisting warping normal stress, MPa Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code f b = flexural stress due to the larger of the two moments at either end of the braced segment, MPa f w / f b is positive when f w is compressive on the outside edge of the curved flange Webs The factored shear resistance shall be calculated in accordance with Clause (a) (neglecting tension field action). The following requirements shall also apply: (a) Webs without stiffeners: transverse stiffeners shall not be required if h/w 150. (b) Webs with transverse stiffeners only: when a a 150 < h/w Fy R +. R transverse stiffeners shall be provided at a spacing a < h. (c) Webs with transverse and longitudinal stiffeners: when a a < h/w < Fy R a a. R Fy R +. R the longitudinal stiffeners shall be provided at a distance 0.2h from the compression flange. When same-size longitudinal stiffeners are located 0.2h from both the compression flange and the tension flange, the web slenderness ratio shall not exceed 6000/ F y. (d) Proportioning of transverse web stiffeners: in addition to meeting the b/t requirements of Clause , stiffeners shall be proportioned so that I aw 3 j where j = 2 h X 05. a where X = = 1.0 when a h 078. a h Z a when 078. < < 10., 0 Z 10, and Z = h Rw I shall be taken about an axis at the mid-plane of the web for stiffener pairs, or at the near face of the web for single stiffeners. 2 a (Replaces p. 479, November 2006) 479

19 S6S1-10 (e) Longitudinal stiffeners shall meet the requirements of Clause (f) Monosymmetric sections: the slenderness ratio of the compression portion of webs of monosymmetric sections with an axis of symmetry in the plane of loading shall not exceed one-half of the applicable value specified in Item (a), (b), or (c). Longitudinal stiffeners, if required, shall be placed 0.4d c from the inner surface of the compression flange Composite I-girders General Clauses to shall apply to simple and continuous span curved I-girders, fastened throughout their full length to a concrete deck by shear connectors Webs The web of the steel girder shall be designed to carry the entire vertical shear in accordance with Clause Flanges Flanges shall be Class 3 or better and meet the strength and stability requirements of Clause Shear connectors Shear connectors shall meet the requirements of Clauses and Composite box girders General Clause shall apply to simple or continuous span curved box girders fastened throughout their length to a concrete deck by shear connectors. The behaviour of a girder before the concrete deck has cured may be analyzed as a quasi-closed section by replacing the lateral bracing with an equivalent plate. The top flanges shall meet the requirements of Clause and the bottom flange shall meet the requirements of Clause Webs The inclination of the webs from the normal to the bottom flange shall not exceed 1 in 4. The webs shall meet the requirements of Clause for combined flexural and torsional shear Top flanges The top flanges of open-box girders shall meet the requirements of Clauses and and the top flanges of closed-box girders shall meet the requirements of Clause In both cases, lateral bending and buckling of the steel flange shall be checked for strength and stability during placement of concrete, but may be assumed to be restrained by the concrete deck when the deck has cured Bottom flanges Tension flanges The factored moment resistance with respect to the tension flange shall be determined using an effective width in accordance with Clause (a) and using a reduced normal stress, R v F y, in place of F y, with R v as follows: 480 (Replaces p. 480, November 2006)

20 Preferably no snipe in web Single groove butt weld on permanent backing bar. Backing bar fillet welds continuous. (a) Welded longitudinal field splice of deck plate 80% penetration 50R a 20 c e h Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code 80% penetration Grind ends of weld do not wrap around Note: c > h/3 (75 mm minimum). (b) Intersection of closed ribs with floor beams 20R Edge of sidewalk (c) Open ribs at floor beams Figure 10.5 Detailing requirements for orthotropic decks (See Clause ) Wearing surface The wearing surface shall be considered an integral part of the orthotropic deck and shall be bonded to the top of the deck plate. The contribution of a wearing surface to the stiffness of the members of an orthotropic deck shall not be considered unless the structural and bonding properties are satisfactorily demonstrated over the design temperature range. If the contribution is considered, the required engineering properties of the wearing surface shall be specified on the Plans. (Replaces p. 487, November 2006) 487

21 S6S1-10 For the purpose of design, the following requirements shall apply: (a) the long-term composite action between the deck plate and the wearing surface shall be demonstrated by both static and dynamic cyclic load tests; (b) the determination of force effects in the wearing surface and at the interface with the steel deck plate shall take into account the engineering properties of the wearing surface at anticipated extreme service temperatures; and (c) the wearing surface shall be assumed to act compositely with the deck plate whether or not the deck plate is designed on that basis Structural fatigue General The FLS considered shall include direct live load effects, i.e., live load-induced fatigue, and the effects of local distortion within the structure, i.e., distortion-induced fatigue Live-load-induced fatigue Calculation of stress range The stress range for load-induced fatigue shall be calculated using ordinary elastic analysis and the principles of mechanics of materials. A more sophisticated analysis shall be required only in cases not covered in Tables 10.7 and 10.8, such as major access holes and cutouts. Because the stress range shall be the algebraic difference between the maximum stress and minimum stress at a given location, only the stresses due to live load shall be considered. At locations where the stresses resulting from the permanent loads are compressive, load-induced fatigue shall be disregarded when the compressive stress is at least twice the maximum tensile live load stress Design criteria For load-induced fatigue, except in bridge decks, each detail shall satisfy the requirement that 0.52C L f sr < F sr where C L = 1.0, except when W > 625 kn and the volume of heavy trucks prompting the use of a level of loading greater than that for CL-625 Trucks constitutes not more than the greater of 200 per day and 5% of the ADTT on the highway, C L = /W f sr = calculated fatigue stress range at the detail due to passage of the CL-W Truck, as specified in Clause For load-induced fatigue in bridge decks, each detail shall satisfy the requirement that 0.62f sr F sr where f sr = calculated fatigue stress range at the detail due to passage of a tandem set of 125 kn axles spaced 1.2 m apart and with a transverse wheel spacing of 1.8 m Fatigue stress range resistance Fatigue stress range resistance of a member or detail The fatigue stress range resistance of a member or a detail, F sr, other than for shear studs or cables, shall be calculated as follows: F sr = ( /N c ) 1/3 F srt / (Replaces p. 488, November 2006)

22 where Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code = fatigue life constant pertaining to the detail category established in accordance with Clause and specified in Table 10.4 N c = 365y N d (ADTT f ) where y = design life (equal to 75 years unless otherwise specified by the Owner or Engineer) N d = number of design stress cycles experienced for each passage of the design truck, as specified in Table 10.5 ADTT f = single-lane average daily truck traffic, as obtained from site-specific traffic forecasts. In lieu of such data, ADTT f shall be estimated as p (ADTT), where p is 1.0, 0.85, or 0.80 for the cases of one, two, or three or more lanes available to trucks, respectively, and ADTT is as specified in Table Fatigue stress range resistance of fillet welds transversely loaded The fatigue stress range resistance, F sr, of fillet welds transversely loaded shall be calculated as a function of the weld size and plate thickness, as follows: F sr = F sr c [( D/t)/(0.64t 1/6 )] where c F sr = fatigue stress range resistance for Category C, as determined in accordance with Clause , based on no penetration of the weld root D = weld leg size, mm t = plate thickness, mm Table 10.4 Fatigue life constants and constant amplitude threshold stress ranges (See Clauses and ) Detail category A B B1 C C1 D E E1 M164 M253 Fatigue life constant, Constant amplitude threshold stress range, F srt, MPa (Replaces p. 489, November 2006) 489

23 S6S1-10 Longitudinal members Simple-span girders Continuous girders Near interior support (within 0.1L on either side) All other locations Cantilever girders Trusses Table 10.5 Values of N d (See Clause ) Span length, L, 12 m Table 10.6 Average daily truck traffic (See Clause ) Span length, L, < 12 m Transverse members Spacing 6 m Spacing < 6 m All cases 1 2 Class of highway A B C D ADTT Detail categories The detail categories shall be as specified in Tables 10.7 and The following details shall be prohibited for use when cyclic loading is present: (a) partial penetration groove welds loaded transversely; and (b) cover plates attached to girder flanges using only fillet welds that are oriented transversely with respect to the direction of stress in the member Width-to-thickness ratios of transversely stiffened webs The width-to-thickness ratios of transversely stiffened webs, h/w, shall not exceed 3150/ F y unless a longitudinal stiffener is provided in accordance with Clause In determining a width-to-thickness ratio, F y may be replaced by the maximum compressive stress due to the factored ULS loads if the maximum shear at the FLS does not exceed V r calculated in accordance with Clause , taking F t = 0 and s = (Replaces p. 490, November 2006)

24 General condition Welded rib splice without backing bar Rib intersection with floor beam Situation Single-groove butt weld without backing bar Table 10.8 (Concluded) Axial stress in rib wall at the lower end of rib to floor beam weld Detail category E1 D Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Illustrative example Deck plate to floor beam connection Deck plate stress parallel to floor beam at deck to floor beam junction D 1 Q e Floor beam web at cutout Vertical stress in floor beam web at floor beam cutout at the bottom of rib. f = stress in floor beam web due to bending moment, V H h, where V H = V LL+I (a + e) Q/I and Q and I are properties of the floor beam cross-section at Section 1-1. D 1 V H f h Fatigue resistance of high-strength bolts loaded in tension High-strength bolts subjected to tensile cyclic loading shall be pretensioned to the minimum preload specified in Clause Connected parts shall be arranged so that prying forces are minimized. The calculated prying force shall not exceed 30% of the externally applied load Fatigue resistance of stud shear connectors Stud shear connectors shall be designed for the following stress range, rs : sc t rs C V Q s = 052. L A I n sc t where C L = 1.0, except when W > 625 kn and the volume of heavy trucks prompting the use of a level of loading greater than that for CL-625 Trucks constitutes not more than the greater of 200 per day and 5% of the ADTT on the highway, C L = /W V sc = design shear force at the section along the length of the beam where the fatigue resistance of the shear connectors is being evaluated, N Q = first moment of area of the transformed section at the interface between the concrete slab and the steel section, mm 3 s = shear stud group spacing, mm A sc = cross-sectional area of a shear stud, mm 2 n = number of shear studs in the group at the cross-section being evaluated I t = moment of inertia of the transformed composite section about the axis of bending, mm 4 Fatigue Category D shall be used to evaluate the fatigue resistance of stud shear connectors. (Replaces p. 499, November 2006) 499

25 S6S1-10 When stud shear connectors are not provided in negative moment regions, additional connectors, N a in number, shall be provided at each location of contraflexure, where N C Af rsr a = 052. L Z sr where Z sr = the allowable range of interface shear in an individual shear connector, given as ( ) 9 13 sr c sc sc Z = N A 24A where N c = number of cycles as specified in Clause These additional connectors shall be placed within a distance equal to one-third of the effective slab width on each side of the point of dead load contraflexure Fatigue resistance of cables Suspension cables and hangers Cables and hangers used in suspension bridge construction need not be designed for fatigue, unless, in the judgment of the Engineer, special fatigue provisions are required Cable-stays and cable-stayed bridge tie-downs Inspectable stays The fatigue stress range for cable-stays and tie-downs that are replaceable without significant loss of function of the bridge, and in which wire breaks can be detected in service, shall not exceed the fatigue stress resistance established by test. An acceptable test is a test of cable and sockets in which the stress range is applied for cycles and, at the end of which, the test stay has at least 0.95 of its specified breaking strength. The lowest stress range of three successful tests shall be taken as the fatigue stress range resistance. For the purpose of this Clause, secondary (bending) stresses shall be calculated, but only secondary stresses exceeding 50 MPa shall be added to the primary (tension) stress to derive the test fatigue stress range Non-inspectable or non-replaceable stays The fatigue stress range resistances for cable stays and tie-downs in which wire breaks cannot be detected while they are in service, or for cable stays and tie-downs that cannot be readily replaced, shall not exceed 0.75 of the fatigue stress range resistance established by test Distortion-induced fatigue General When members designed in accordance with Clause for load-induced fatigue are provided with interconnection components such as diaphragms, cross-bracing, and lateral bracing, both the members and the interconnection components shall be examined for distortion-induced fatigue. Wherever practicable, elements of the primary member shall be fastened to the interconnection member unless otherwise Approved. The requirements for controlling web buckling and flexing of girder webs specified in Clause shall apply. 500 (Replaces p. 500, November 2006)

26 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Connection of diaphragms, cross-frames, lateral bracing, and floor beams Connection to transverse elements Unless otherwise Approved, the connections of diaphragms, including internal diaphragms, cross-frames, lateral bracing, floor beams, etc., to main members shall be made using transverse connection plates that are welded or bolted to both the tension and compression flanges of the main member. If transverse stiffeners of the main members form part of the connection, they shall be similarly connected. In straight non-skewed bridges, the connections shall be designed to resist a factored horizontal force of 90 kn unless a more exact value is determined by analysis Connection to lateral elements If connections of diaphragms, including internal diaphragms, cross-frames, lateral bracing, floor beams, etc., are to be made to elements that are parallel to the longitudinal axis of the main member, the lateral connection plates shall be attached to both the tension and compression flanges of the main member. Where this is not practicable, then lateral connection plates shall be located as follows: (a) Transversely stiffened girders: where lateral connection plates are fastened to a transversely stiffened girder, the attachment shall be located at a vertical distance not less than one-half the flange width from the flange. If located within the depth of the web, the lateral connection plate shall be centred with respect to the transverse stiffener, whether or not the stiffener and the connection plate are on opposite sides of the web. If the lateral connection plate and the transverse stiffener are located on the same side of the web, the plate shall be attached to the stiffener. Transverse stiffeners at locations where lateral connection plates are attached shall be continuous between the flanges and shall be fastened to them. Bracing members attached to the lateral connection plates shall be located so that their ends are at least 100 mm from the face of the girder web and the transverse stiffener. (b) Transversely unstiffened girders: lateral connection plates may be fastened to a transversely unstiffened girder, provided that the attachment is located a vertical distance not less than one-half the flange width or 150 mm from the flange. Bracing members attached to the lateral connection plates shall be located so that their ends are at least 100 mm from the face of the girder web Orthotropic decks Distortion-induced fatigue shall be minimized through appropriate detailing in accordance with Clause The stress ranges for live-load-induced fatigue shall be as specified in Clause Splices and connections General General design considerations Splices and connections shall be designed at the ULS for the larger of (a) the calculated forces at the splice or connection; or (b) 75% of the factored resistance of the member, such resistance to be based on the condition of tension, compression, bending, or shear that governed selection of the member. Except for handrails and non-load-carrying components, connections shall contain at least two 16 mm diameter high-strength bolts or equivalent welds Alignment of axially loaded members When the centroidal axes of axially loaded members meeting at a joint do not intersect at a common point, the effect of joint eccentricity shall be considered. (Replaces p. 501, November 2006) 501

27 S6S Proportioning of splices and connections Splices and connections shall be designed for all of the forces, including axial, bending, and shear forces, that can occur in the connected components (allowing for any eccentricity of loading). Where the fatigue requirements of Clause govern the design, the connections shall be designed to the same requirements Compression members finished to bear At the ends of compression members that are finished to bear, splice material and connecting bolts or welds shall be arranged to hold all of the components in place and shall be proportioned to resist not less than 50% of the force effects at the ULS Beam and girder connections End connections for beams and girders that are proportioned to resist vertical reactions only shall be detailed to minimize the flexural end restraint, except that inelastic action in the connection at the SLS shall be permitted in order to accommodate the end rotations of unrestrained simple beams. The connections of beams and girders subject to both reaction shear and end moment due to rigid, continuous, or cantilever construction shall be proportioned for the loads at the ULS. Axial forces, if present, shall also be considered. Coping of flanges at connections may be used for secondary members in bridges with straight girders. Coping of flanges at connections of floor beams and main girders shall not be permitted. Blocks shall be used instead of copes whenever possible Bolted connections General All high-strength bolts shall be pretensioned in accordance with Clause Bolts in tension Tensile resistance at the ultimate limit states The factored tensile resistance, T r, developed by the bolts in a bolted joint subject to tension, T f, shall be taken as T r = 0.75 b n A b F u where F u = specified ultimate tensile strength of the bolt material Bolts in tension shall be proportioned to resist the factored tensile force, T f, taken as the sum of the factored external load and any additional tension resulting from prying action produced by the deformations of the connected parts, but neglecting bolt pretension Tensile resistance at the fatigue limit state High-strength bolts subjected to tensile cyclic loading shall meet the requirements of Clause Bolted joints in shear General Bolted joints required to resist shear between the connected parts shall be designed as slip-critical connections at FLS and SLS, except for connections of bracing members in straight girder bridges and connections not subjected to stress reversal. 502 (Replaces p. 502, November 2006)

28 Slip resistance at the service load levels Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The slip resistance, V s, of a bolted joint in a slip-critical connection subjected to shear, V, shall be taken as V s = 0.53c 1 k s mna b F u where k s = mean slip coefficient determined in accordance with Table 10.9 or by Approved tests c 1 = coefficient that relates the specified initial tension and mean slip to a 5% probability of slip for bolts installed by turn-of-nut procedures, as specified in Table 10.9 For installation using other procedures, different values of c 1 apply. In long-slotted holes, the shear resistance shall be taken as 0.75V s. A slip-critical connection shall also satisfy the shear and bearing criteria at the ULS. Contact surface of bolted parts Class Description Table 10.9 Values of k s and c 1 (See Clauses and ) k s c 1 (ASTM A 325 and ASTM F 1852) A Clean mill-scale or blast cleaned with Class A coatings c 1 (ASTM A 490 and ASTM F 2280) B Blast-cleaned surfaces or blast-cleaned surface with Class B coatings C Hot-dip galvanized with hand wire-brushed surfaces Note: Class A and B coatings are those coatings that provide a mean slip-coefficient of not less than 0.33 and 0.50, respectively. Values of c 1 for a 5% probability of slip for values of k s other than those specified in this Table shall be determined by an Approved means Shear resistance at the ultimate limit states The factored shear resistance of a bolted joint subject to a shear force, V f, shall be taken as the lesser of (a) the bearing resistance, B r, of the plate adjacent to the bolts, as follows: (b) B r = 3 br ntdf u where F u = ultimate strength of the plate br = 0.80 the shear resistance, V r, of the bolts, as follows: V r where F u = 0.60 b nma b F u = ultimate strength of the bolt material For axially loaded lap splices with shear transfer length > 760 mm: V r = 0.50 b nma b F u If any bolt threads are intercepted by a shear plane, the factored shear resistance of the joint shall be taken as 0.7V r. (Replaces p. 503, November 2006) 503

29 S6S Bolts in shear and tension Resistance at the serviceability limit states Bolts in a connection subjected to loads that cause shear, V, and tension, T, shall satisfy the following relationship: V V T na F 10. s b u The requirements of Clause shall also be met Resistance at the ultimate limit states A bolt that is required to resist a tensile force and a shear force at the ULS shall satisfy the following relationship: 2 2 Vf Tf V + r Tr Welds General Welding design shall comply with CSA W59, except as otherwise specified in Clause The matching electrode classifications for CSA G40.21 and CSA W59 steels shall be as specified in Table Table Matching electrode classifications for CSA G40.21 and CSA W59 steels (See Clause ) Matching electrode* CSA G40.21 grade X X X X X X X X X *The number indicates the tensile strength of the weld metal in megapascals, as indicated in the electrode classification number. For hollow structural steel sections only. For uncoated applications using A or AT steels, where the deposited weld metal is to have atmospheric corrosion resistance and/or corrosion characteristics similar to those of the base metal, the requirements of Clauses and of CSA W59 shall apply Shear Complete and partial joint penetration groove welds The factored shear resistance,v r, shall be taken as the lesser of (a) for base metal: V r = 0.67 w A m F u 504 (Replaces p. 504, November 2006)

30 (b) for weld metal: V r = 0.67 w A w X u Fillet welds Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The factored resistance for tension- or compression-induced shear, V r, shall be taken as the lesser of (a) for base metal: (b) V r = 0.67 w A m F u for weld metal: V r = 0.67 w A w X u ( sin 1.5 ) R w where = angle between the axis of the weld segment and the line of action of the applied force (e.g., 0 for a longitudinal weld and 90 for a transverse weld) R w = strength reduction factor. = 1.0 for the weld segment with the largest = 0.85 for the other weld segments Note: It is a conservative simplification to take the bracketed quantity in Item (b) equal to Tension normal to the weld axis Complete joint penetration groove welds shall be made with matching electrodes. The factored tensile resistance shall be taken as that of the base metal Compression normal to the weld axis Complete and partial joint penetration groove welds shall be made with matching electrodes. The factored compressive resistance shall be taken as that of the effective area of the base metal in the joint. For partial penetration groove welds, the effective area in compression shall be taken as the nominal area of the fusion face normal to the compression plus the area of the base metal fitted to bear Hollow structural sections The provisions of Appendix L of CSA W59 should be applied to hollow structural sections. Note: Use of these provisions is strongly recommended Detailing of bolted connections Contact of bolted parts Bolted parts shall fit together solidly when assembled and shall not be separated by gaskets or any other interposed compressible material Hole size The nominal diameter of a hole shall not be more than 2 mm greater than the nominal bolt size, except that where shown on the Plans, oversize or slotted holes may be used with high-strength ASTM A 325 or ASTM A 490 bolts 5/8 in or larger in diameter, or with ASTM A 325M or ASTM A 490M bolts 16 mm or larger in diameter. Joints with oversize or slotted holes shall meet the following requirements: (a) Oversize holes shall not be more than 4 mm larger than bolts 22 mm or less in diameter, not more than 6 mm larger than bolts 24 mm in diameter, and not more than 8 mm larger than bolts 27 mm or more in diameter. Oversize holes used in any plies of connections shall be provided with hardened washers under heads or nuts adjacent to plies containing oversize holes. (Replaces p. 505, November 2006) 505

31 S6S1-10 (b) (c) (d) (e) Short slotted holes shall not be more than 2 mm wider than the bolt diameter and shall not have a length that exceeds the oversize diameter requirements of Item (a) by more than 2 mm. When used in any plies of connections, hardened washers shall be provided under heads or nuts adjacent to plies containing slotted holes. Long slotted holes shall not be more than 2 mm wider than the bolt diameter and shall not be greater than 2.5 times the bolt diameter. They shall also comply with the following requirements: (i) when the slotted hole is normal to the direction of the load, the shear resistance shall be as specified in Clause ; (ii) they shall be used in only one of the connected parts at a given faying surface; and (iii) structural plate washers or a continuous bar not less than 8 mm thick shall cover long slots that are in the outer plies of joints after installation. When ASTM A 490 or ASTM A 490M bolts larger than 26 mm in diameter are used in oversize or slotted holes in outer plies, the hardened washers shall be at least 8 mm thick and comply with ASTM F 436. The requirements for the nominal diameter of a hole shall not preclude the use of the following bolt diameters and hole combinations: (i) a 3/4 in bolt or an M20 bolt in a 22 mm diameter hole; (ii) a 7/8 in bolt or an M22 bolt in a 24 mm diameter hole; and (iii) a 1 in bolt or an M24 bolt in a 27 mm diameter hole Coatings The faying surfaces of slip-critical connections shall be shown on the Plans as coated or uncoated. Where faying surfaces are to be coated, one of the following processes shall be used: (a) hot-dip galvanizing, provided that the faying surfaces are hand wire-brushed after galvanizing and before assembly; (b) sprayed-zinc coatings, applied in accordance with CSA G189; or (c) other Approved materials and methods, provided that these have been tested in accordance with the Specification for Structural Joints Using ASTM A325 or A490 Bolts issued by the Research Council on Structural Connections Bolt spacing The minimum distance between centres of bolt holes shall not be less than 3 bolt diameters wherever practicable and never less than 2.7 diameters. The maximum bolt spacing shall be governed by the requirements for sealing or stitching specified in Clauses to Sealing bolts For sealing bolts, the pitch, p, between bolts on a single line adjacent to a free edge of an outside plate or shape shall be equal to or less than ( t) 180 When a second line of fasteners is uniformly staggered with those in the line adjacent to the free edge, at a gauge less than t therefrom, the staggered pitch, p, in two such lines considered together shall be equal to or less than t g 180 d or one-half the requirement for a single line, whichever is greater. 506 (Replaces p. 506, November 2006)

32 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Stitch bolts Unless closer spacing is required for transfer of load or for sealing inaccessible surfaces, the longitudinal spacing in-line between intermediate bolts in built-up compression members shall not exceed 12t. The gauge, g, between adjacent lines of bolts shall not exceed 24t. The staggered pitch between two adjacent lines of staggered holes shall not exceed g p 15 t 3 t 8 12 The pitch for tension members shall not exceed twice that specified for compression members. The gauge for tension members shall not exceed 24t. 506A

33

34 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Stiffener connection and stiffener length Stiffeners shall be connected so that the force in the stiffener is transferred through the stiffener connection. When beams frame to one side of a column only, the stiffeners need not be longer than one-half the depth of the column Anchor rods General Anchors provided to connect the superstructure to the substructure shall be proportioned to withstand the effect of uplift forces, bending moments, and shear at the ULS determined in accordance with Sections 3 and 5. Anchor rods for bearing assemblies shall have a minimum diameter of 30 mm and a minimum embedment length of 300 mm. The compression resistance of the concrete, the anchorage of rods, the shear resistance between the baseplate and substructure, and the moment resistance of anchorage systems shall be determined in accordance with Clause Anchor rod resistance Tension The factored tensile resistance, T r, of an anchor rod shall be taken as T r = b A s F u where A s = tensile stress area π = 4 ( d p) 2 where p = pitch of threads, mm Shear The factored shear resistance, V r, of an anchor rod shall be taken as V r = 0.60 b n A b F u but not be greater than the lateral bearing resistance specified in Clause When rod threads are intercepted by the shear plane, the factored resistance shall be taken as 0.70V r Combined tension and shear An anchor rod required to develop resistance to both tension and shear shall be proportioned so that 2 2 Vf Tf V + r Tr 10. where V r = portion of the total shear per rod transmitted by bearing of the anchor rods on the concrete, as required by Section 8 (Replaces p. 509, November 2006) 509

35 S6S Combined tension and bending Anchor rods required to develop resistance to both tension and bending shall be proportioned to meet the requirements of Clause The tensile and moment resistances, T r and M r, respectively, shall be based on the properties of the cross-section at the critical section; M r shall be taken as b SF y Pins, rollers, and rockers Bearing resistance The factored bearing resistance, B r, developed by a component or portion of a component subjected to bearing shall be calculated as follows: (a) on the contact area of machined, accurately sawn, or fitted parts and on the bearing area of pins: (b) B r = 1.50 s F y A where the bearing area of pins is taken as the pin diameter multiplied by the thickness of the connected parts; and on expansion rollers or rockers: B where F y = specified minimum yield point of the weaker part in contact Pins R1 R 1 R LF 2 r = fs y Bending resistance The factored bending resistance of a pin shall be taken as M r = s SF y Shear resistance The factored shear resistance of a pin shall be taken as V r = 0.60 s AF y Combined bending and shear Sections of pins subject to both bending and shear shall be proportioned so that Mf M r Vf + Vr Pin connection details Pins shall be of sufficient length to ensure full bearing of all parts connected to the turned body of the pin. They shall be secured in position by hexagonal recessed nuts or by hexagonal solid nuts with washers or, if the pins are bored, by throughrods with recessed cap washers. Pin nuts shall be malleable steel castings or steel and shall be secured by cotter pins in the screw ends or with locknuts. Pins shall be located so as to minimize the force effects due to eccentricity. Pin plates shall contain sufficient welds or fasteners to distribute their portion of the pin load to the full cross-section of the component with due consideration given to the effects of eccentricity. 510 (Replaces p. 510, November 2006)

36 10.21 Torsion Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code General Members and their connections subjected to torsion shall have sufficient strength and rigidity to resist the torsional moments and forces in addition to other moments and forces. The torsional deformations at the SLS shall be within acceptable limits Members of closed cross-section Torsional resistance The factored torsional resistance, Q r, taking the warping constant, C w, to be zero, shall be calculated as Q r 2 = sfyat 3 f where t = minimum thickness of material, provided that the width-to-thickness ratios of elements are (a) for flat plate elements: (b) b/t 1100/ F y for circular hollow sections (or multi-sided hollow sections that approximate a circle): D/t / F y When a width-to-thickness ratio exceeds a ratio specified in Item (a) or (b), as applicable, the torsional resistance shall be calculated using an elastic analysis Combined axial compression, flexure, and torsion Members of closed cross-section subject to combined axial compression, flexure, and torsion shall be proportioned so that C C f r + M r M f C 1 C f e Qf + Qr where C r is as specified in Clause , M r is as specified in Clause 10.10, and Q r is as specified in Clause Reinforcement of cut-outs Members with cut-outs whose torsional design is based on the cross-sectional properties of the closed cross-section shall be detailed as follows: (a) cut-outs shall have semicircular ends; (b) the width of a cut-out shall not exceed 0.17 times the circumference of the member; (c) a stiffener shall be provided around the perimeter of the cutout and welded to develop the full cross-section of the wall. The stiffener shall have a cross-sectional area, A, of A = L( t/ 3) where L = length of the cut-out measured parallel to the longitudinal axis of the member t = thickness of the wall of the member (d) the width-to-thickness ratio of the outstanding portions of the stiffener shall not exceed 170/. F y (Replaces p. 511, November 2006) 511

37 S6S Members of open cross-section St. Venant torsional constant The St. Venant torsional constant shall be calculated as 3 bt J = S 3 where b = length of the plate element t = thickness of the plate element The width-to-thickness ratios of elements shall meet the requirements of Clause Warping constant The warping constant, C w, shall be calculated as follows: (a) for a doubly symmetric I-shaped section: 2 lh y Cw = 4 (b) for a monosymmetric I-shaped section: C w hly ly = ( ly1+ ly2) (c) where I y = moment of inertia about the minor axis I y1, I y2 = moment of inertia of the upper and lower flanges, respectively, about the y-axis of symmetry for a closed rectangular section: C 2 2 w = 2lf w where I f = d b I bt 12 I w = dw Torsional resistance The factored torsional resistance of members of open cross-section shall be calculated based on accepted principles of elastic torsional analysis, taking into account the St. Venant and warping torsional resistance as a function of the loading and restraint conditions Combined bending and torsion For I-shaped members subject to torsion or combined bending and torsion, the maximum combined normal stress due to warping torsion and bending at SLS loads, as determined by an elastic analysis, shall not exceed F y. 512 (Replaces p. 512, November 2006)

38 10.22 Steel piles Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code General The structural design of steel piles shall be in accordance with this Section. The geotechnical design shall be in accordance with Section Resistance factors The resistance factor to be used when calculating the factored axial compressive resistance for piles under axial compression alone in accordance with Clause shall be The factor given in Clause shall also apply unless the pile is not driven into the soil but rather lowered into a pre-augered hole. When calculating the resistance of the pile above the point of fixity, the resistance factors for coincident axial compression and bending shall be 0.70 for compression and 0.95 for flexure Compressive resistance Axial compression For piles under axial compression alone, the factored axial compressive loads shall not exceed the factored compressive resistance specified in Clause Combined axial compression and bending Piles under coincident axial compression and bending shall satisfy the following: (a) The factored axial compressive loads shall not exceed the axial compressive resistance of the pile, as calculated under Clause (b) The coincident axial compressive and flexural loads and resistance of the pile above the point of fixity shall satisfy the requirements of Clause Unsupported length For piles that are subjected to axial compression alone and are fully embedded in soil, the unsupported length, L, shall be taken as zero. If the pile extends above the ground surface in air or water, or is subjected to combined axial compression and bending, the unsupported length of the pile shall include the length of the pile above the soil, if any, plus an embedded depth to fixity Effective length factor The effective length factor, K, shall be determined on the basis of the restraint provided by the soil, the pile cap, the structure, and the substructure, as specified in Section Splices Splices shall be proportioned to develop the full cross-sectional strength of the pile Welding Welding shall be in accordance with Clause Composite tube piles For composite tube piles, the applicable requirements of Clause shall be met. (Replaces p. 513, November 2006) 513

39 S6S Fracture control General Fracture control shall be considered throughout material selection and structural design. Consideration shall be given to (a) designation of fracture-critical and primary tension members; (b) the level of quality control, inspection, and monitoring during fabrication; (c) the likelihood of crack initiation and crack growth; (d) selection of steel and welding consumables with appropriate toughness; and (e) controlling stress concentrations and improper alignment Identification The components identified as fracture-critical members and primary tension members shall be clearly identified in the Plans. Shop drawings shall identify the extent of fracture-critical and primary tension members. Attachments longer than 100 mm in the direction of tension and welded to the tension zone of a fracture-critical or primary tension member shall be treated as part of that member. For each component of a fracture-critical or primary tension member, records shall be kept to identify the heat number of the material and its corresponding mill test certificate. The fracture-toughness and welding requirements of Clauses to shall apply only to members designated as fracture-critical and primary tension members Fracture toughness General The Charpy V-notch requirements specified in Clause shall apply only to standard full-size specimens. For plates from 8 to 11 mm thick, subsize specimens with adjusted energy levels may be used, as permitted by CSA G The requirements of Clause shall apply to both bolted and welded construction Fracture-critical members For fracture-critical members, Charpy V-notch tests shall be specified on a per plate frequency, as defined in CSA G40.20/G The steel shall meet the impact energy requirements specified in Table Primary tension members For primary tension members, Charpy V-notch tests shall be specified on a per heat frequency, as defined in CSA G40.20/G The steel shall meet the impact energy requirements specified in Table Service temperature The applicable minimum service temperature, T s, shall be the minimum daily mean temperature in Figure A Weld metal toughness For fracture-critical and primary tension members, the weld metal shall meet the impact energy requirements of (a) Clause ; and (b) Tables 10.14A and 10.14B, respectively Steel for permanent backing bars Steel for permanent backing bars shall meet the requirements of Clause of CSA W59 and shall meet the Charpy impact energy requirements of Table or 10.13, as applicable. 514 (Replaces p. 514, November 2006)

40 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Table Impact test temperatures and Charpy impact energy requirements for fracture-critical members (See Clauses , , and ) CSA G40.21 grade Commonly used steels 260 WT 300 WT 350 WT and AT 400 WT and AT Minimum average energy, J Steels requiring Approval 480 WT and AT 700 QT Test temperature, T t, C, for minimum service temperature, T s, C T s > T s 60 T s < Table Impact test temperatures and Charpy impact energy requirements for primary tension members (See Clauses , , and ) CSA G40.21 grade Minimum average energy, J Test temperature, T t, C, for minimum service temperature, T s, C T s > T s 60 T s < 60 Commonly used steels 260 WT 300 WT 350 WT and AT 400 WT and AT Steels requiring Approval 480 WT and AT 700 QT A

41

42 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Table 10.14A Impact test temperatures and Charpy impact energy requirements for weld metal in fracture-critical members (See Clauses and ) Base metal CSA G40.21 grade 260 WT 300 WT 350 WT and AT 400 WT and AT 480 WT and AT 700 QT Minimum average energy, J Test temperature, T t, C, for minimum service temperature, T s, C T s > T s 60 T s < * * * * *Welded construction using 480WT and 700QT steels shall require Approval and special considerations. Joining by bolting is recommended for these applications. Table 10.14B Impact test temperatures and Charpy impact energy requirements for weld metal in primary tension members (See Clauses and ) Base metal CSA G40.21 grade Minimum average energy, J Test temperature, T t, C, for minimum service temperature, T s, C T s 40 T s < WT 300 WT 350 WT and AT 400 WT and AT 480 WT and AT 700 QT Welding of fracture-critical and primary tension members General The requirements of Clauses to and shall apply to the welding of fracture-critical and primary tension members Welding consumables Except as permitted by Clause , only welding consumables with Charpy V-notch toughness requirements in compliance with Tables 10.14A and 10.14B, as applicable, and certified by the Canadian Welding Bureau to CAN/CSA-W48 shall be used. In the absence of an applicable CAN/CSA-W48 requirement, the applicable Standard(s) in the American Welding Society A5 series of Standards shall be used. In groove welds connecting two different grades of steel, the classification of consumables used, including Charpy V-notch impact requirements, shall be that applicable to the grade with the lower ultimate tensile strength. (Replaces p. 515, November 2006) 515

43 S6S Approval and verification of consumables For groove welds in fracture-critical and primary tension members using certified consumables where the Charpy V-notch test temperature required by Tables 10.14A and 10.14B is lower than the test temperature required by CAN/CSA-W48 or the applicable Standard(s) in the American Welding Society A5 series of Standards, or where these Standards are not applicable, welding consumables shall be Approved by the Canadian Welding Bureau and qualified using a verification test assembly to establish the impact properties of the weld metal. The test procedures shall be those specified in CAN/CSA-W48 or the applicable American Welding Society Standard, except that only Charpy V-notch tests shall be required and welding shall be carried out using the preheat and the maximum heat input to be used in practice. The Charpy V-notch results shall meet the requirements of Table 10.14A or 10.14B, as applicable. Qualification shall be required for each electrode diameter used and for the consumables supplied by each manufacturer. The qualification shall be valid for consumables for all groove weld procedures that use a heat input the same as or lower than that used in the qualification test Welding 700Q and 700QT steels For groove weld procedures involving fracture-critical and primary tension members made of 700Q and 700QT steels, consumables shall be qualified by welding procedure tests and Approved by the Canadian Welding Bureau. The tests shall be conducted in accordance with CSA W47.1 using 700Q or 700QT steels for the base plate and shall include weld metal and heat-affected zone (HAZ) Charpy V-notch impact tests in accordance with Appendix E of CSA W47.1. Weld metal impact tests shall meet the requirements of Table 10.14A or 10.14B, as applicable, and HAZ impact tests shall meet the requirements of Tables or for the base plate, as applicable. Only manufacturers of qualified consumables shall supply consumables for fabrication. The qualification shall be valid for all groove weld procedures that use a heat input the same as or lower than that used in the qualification test Qualification of consumables When the welding consumables have not previously been certified by the Canadian Welding Bureau, they shall be qualified by welding procedure tests in accordance with Clause (b) of CSA W47.1 and shall include Charpy V-notch impact tests of the weld metal. For steels other than 700Q and 700QT Charpy V-notch tests in the HAZ shall not be required. Weld metal Charpy V-notch properties shall be established by qualification tests in accordance with CSA W47.1 (including Appendix E) and shall meet the requirements of Tables 10.14A and 10.14B, as applicable. Only manufacturers of qualified consumables shall supply consumables for fabrication. Qualification testing shall be performed for each lot or batch of consumables. The qualification shall be valid for all weld procedures that use a heat input the same as or lower than that used in the qualification test. Consumables for 700Q and 700QT steels shall be qualified in accordance with Clause Tack welds and temporary welds Tack welds shall not be used on fracture-critical or primary tension members unless they are incorporated into the final weld. Temporary welds shall not be used on fracture-critical or primary tension members, or on flange material in compression, unless Approved Welding corrections and repairs to fracture-critical members General Except as specified in Clause (c), repairs to base metal and to welded joints shall be documented. The documentation shall include all of the details specified in Clauses and Welding repair procedures shall be Approved by the Engineer in accordance with Clauses and , as applicable Repair of base metal Repair of base metal by welding at the producing mill shall not be permitted. 516 (Replaces p. 516, November 2006)

44 Table Minimum elapsed time for acceptance testing (See Clause ) Plate thickness, t, mm t 50 t > 50 Magnetic particle for fillet welds 24 h 24 h Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Ultrasonic examination of groove welds Compliance with Approved procedures All repair welding and non-destructive testing shall be performed as described in the Approved repair procedure Records Approved critical repair procedures shall be retained as part of the project records Non-destructive testing of fracture-critical members The use of Cobalt 60 as a radiographic source in quality control shall be permitted only when the steel being tested is more than 75 mm thick. The Constructor shall maintain documentation of all visual and non-destructive testing for review and confirmation by the Engineer. The documentation shall be submitted to the Engineer on completion of the project. 24 h 48 h Construction requirements for structural steel General Clauses to specify requirements for the construction of structural steel for highway bridges and applies unless otherwise specified by the authority having jurisdiction. The requirements specified in these Clauses are provided to ensure compliance with the design philosophy of this Section Submissions General Erection diagrams, shop details, welding procedures, and erection procedure drawings and calculations shall be submitted to the Owner. This requirement shall be stipulated on the Plans Erection diagrams Erection diagrams are general-arrangement drawings showing or indicating the principal dimensions of the bridge, piece marks, the sizes of all members, field welding requirements, the sizes and types of bolts, and bolt installation requirements Shop details Shop details shall provide (a) full detail dimensions and sizes of all component parts of the structure. These dimensions shall make allowance for changes in shape due to weld shrinkage, camber, and any other effects that cause finished dimensions to differ from initial dimensions; (b) all necessary specifications for the materials to be used; (c) identification of areas requiring special surface treatment; (d) identification of fracture-critical and primary tension members and component parts; (Replaces p. 519, November 2006) 519

45 S6S1-10 (e) (f) bolt installation requirements; and details of all welds Welding procedures Welding procedures shall comply with CSA W Erection procedure drawings and calculations The erection procedure drawings and calculations shall fully indicate the proposed method of erection, including the sequence of erection, the weights and lifting points of the members, and the location and lifting capacities of the cranes used to lift them. Details of temporary bracing and bents to be used during construction shall be shown. Calculations shall be provided to show that members and supports are not overloaded during erection Symbols for welding and non-destructive testing The symbols for welding and non-destructive testing on shop drawings shall be in accordance with CSA W Materials Steel Substitution of steel members or components for size and grade shall not be permitted unless Approved. All steel shall be new. Acceptance of any material by an inspector shall not preclude subsequent rejection of the material if it is found defective High-strength bolts, nuts, and washers Nuts and bolts shall be shipped together as an assembly. The nuts of galvanized fasteners shall be overtapped by the minimum amount required for assembly and shall be lubricated with a lubricant containing a visible dye. The use of a mechanically deposited zinc coating shall require Approval Deleted Deleted Fabrication Quality of work The standards for quality of work and finish shall comply with the best modern practices for steel bridge fabrication (with particular attention to the appearance of parts exposed to view) Storage of materials Plain or fabricated structural steel shall be stored above the ground on skids or other supports and kept free from dirt and other foreign matter. Long members shall be adequately supported to prevent excessive deflection Plates Direction of rolling Unless otherwise shown on the Plans, steel plates for main members (and their splice plates) shall be cut so that the primary direction of rolling is parallel to the direction of tensile or compressive stress. 520 (Replaces p. 520, November 2006)

46 Plate edges Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Sheared edges of plates more than 16 mm thick and carrying calculated tension shall be planed, milled, or ground a minimum of 3 mm. Oxygen cutting of structural steel shall be done by machine, except that hand-guided cutting shall be allowed for copes, blocks, and similar cuts where machine cutting is impracticable. Re-entrant corners shall be free from notches and shall have a fillet of the largest practical radius, but not less than 25 mm. The quality and repair of the cut edges shall comply with Clause 5 of CSA W59. All cut edges shall have a surface roughness not greater than 1000, as specified by CSA B95. Corners of oxygen-cut girder flange tips shall be chamfered 2.0 mm by grinding Camber in web plates Webs shall be cut to the prescribed camber, with allowance for shrinkage due to cutting and subsequent welding. The requirements of Clauses and shall also apply Bent plates The following requirements shall apply to bent plates: (a) Load-carrying, rolled steel plates to be bent shall (i) be cut from the stock plates so that the bend line is at right angles to the direction of rolling, except as otherwise Approved for orthotropic decks; and (ii) have their corners lightly chamfered by grinding in the region of the bend before bending. (b) Cold bending shall be carried out so that no cracking or tearing of the plate occurs. Minimum bend radii, measured to the concave face of the metal, shall be as shown in Table (c) Hot bending at a plate temperature not greater than 600 C shall be used to form radii less than those specified for cold bending. Accelerated cooling using compressed air or water shall be used for a hot bent component only when its temperature is below 300 C. Table Minimum bend radii for bent plates (See Clause ) t, mm Minimum radius 12 or less 2t Over 12 to t Over 25 to 38 3t Over 38 to t Over 65 to 100 4t Straightening material All steel shall be flat and straight before being worked. Steel with sharp kinks or bends may be rejected. Attempts to straighten sharp kinks or bends shall require Approval. Rolled plates, sections, and built-up members may be straightened using mechanical means or by the application of a controlled heating procedure in accordance with Clause of CSA W59. After straightening of a bend or buckle, the surface of the steel shall be examined for evidence of fracture or other damage and corrective action taken if necessary. (Replaces p. 521, November 2006) 521

47 S6S Bolt holes General All holes shall be drilled or reamed to the finished diameter, except that punched holes shall be allowed in material up to 16 mm thick. When shown on the Plans, oversize or slotted holes in accordance with Clause are permitted Punched holes The diameter of a punched hole shall be not more than 2 mm larger than the nominal diameter of the bolt unless oversize holes are specified. The diameter of the die shall not exceed the diameter of the punch by more than 2 mm. Holes shall be clean cut and without ragged or torn edges, but the lightly conical hole that results from clean cutting shall be acceptable. Holes may be reamed to admit fasteners Reamed holes Holes that are to be reamed to final diameter shall first be subdrilled or subpunched to 4 mm smaller than the nominal diameter of the bolt. With the connecting parts assembled and securely held, the holes shall then be reamed to 2 mm larger than the nominal diameter of the bolts. The parts shall be match-marked before disassembly Drilled holes Holes that are drilled full-size shall be 2 mm larger than the nominal diameter of the bolt unless oversize holes have been specified. They shall be accurately located by using suitable numerically controlled drilling equipment, or by using a steel template carefully positioned and clamped to the steel. The accuracy of the holes prepared in this manner, and their locations, shall be such that like parts are identical and require no match-marking. The holes for any connection may be drilled full-size when the connecting parts are assembled and clamped in position, in which case the parts shall be match-marked before disassembly Pins and rollers Pins and rollers shall be accurately turned to the dimensions and finish shown on the drawings and shall be straight and free from flaws. Pins and rollers more than 175 mm in diameter shall be forged and annealed. Pins and rollers 175 mm or less in diameter may be either forged and annealed or of cold-finished carbon-steel shafting. Holes for pins shall be bored to the specified diameter and finish at right angles to the axis of the member. The diameter of the pin hole shall not exceed that of the pin by more than 0.5 mm for pins 125 mm or less in diameter or more than 0.75 mm for larger pins. Pin holes shall be bored on completion of the assembly of built-up members Curved girders General Flanges of curved, welded I-girders may be cut to the radius. However, they may be curved by applying heat if the radius, R, is greater than mm and also exceeds 37bh f 51700bf and Fyy w Fyy where F y = specified minimum yield stress of the web 522 (Replaces p. 522, November 2006)

48 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Heat curving of rolled beams and welded girders Steel beams and girders with a specified minimum yield point greater than 350 MPa shall not be heat curved. In heat curving using the continuous or V-type heating pattern, the temperature of the steel shall not exceed 600 C, as measured by temperature-indicating crayons. A detailed procedure for the heat-curving operation shall be submitted for review. The procedure shall describe the type of heating to be employed, the extent of the heating patterns, the sequence of operations, and the method of support of the girder, including an assessment of any dead-load stresses present during the operation. Transverse web stiffeners may be welded in place either before or after the heat-curving operation. However, unless allowance is made for the longitudinal shrinkage, bracing connection plates and bearing stiffeners shall be located and welded after curving. Girders shall be cambered before heat curving. Rolled sections may be heat cambered using an Approved procedure. Plate girders shall have the required camber cut into the web, with suitable allowance for camber loss due to cutting, welding, and heat curving Identification marking Each member shall carry an erection mark for identification. Low-stress stamps stamps with blunt-nosed markings may be used on low-stress areas of main members or on secondary members as a means of permanent identification Welded construction General All welding procedures, including those related to quality of work, techniques, repairs, and qualifications, shall comply with CSA W47.1 and CSA W59, except where modified by Clauses to Processes with limited application The electroslag and electrogas welding processes specified in Clause 5 of CSA W59 shall not be used for welding quenched and tempered steels or for welding components of members subject to tension stress or stress reversal Primary tension and fracture-critical members Members and components of members designated primary-tension or fracture-critical shall meet the requirements of Clause in addition to the requirements of CSA W59. The use of heat to alter the sweep or camber of fracture-critical girders shall require Approval Submissions CWB-accepted welding procedure specifications, data sheets, and repair procedures for prequalification shall be submitted to the Owner in compliance with the Plans Certification of welding operations Any company undertaking welded fabrication and/or welded erection (including steel piles, railings and guards, or other welded attachments) shall be certified to Division 1 or 2 of CSA W Complete joint penetration groove welds Complete joint penetration groove welds shall conform to CSA W59, Clause 12. Runoff tabs or extension bars shall be provided so that groove welds terminate on the tab and shall be removed upon completion of the joint. The welds that attach the tabs to the piece being welded shall be placed inside the joint so that they are incorporated into the final weld. The conditions for the type, use, and removal of the welding backing bar, if used, shall comply with CSA W59, Clause 12, or as otherwise directed by the Engineer. (Replaces p. 523 November 2006) 523

49 S6S Web to flange fillet welds Where practicable, web to flange fillet welds shall be made continuously by machine or automatic welding. Welds may be repaired using either a semi-automatic or manual process, but the repaired weld shall blend smoothly with the adjacent welds Bolted construction General Clauses to specify requirements for bolted steel construction using ASTM A 325/A 325M or ASTM A 490/A 490M high-strength bolts Assembly When assembled, all joint surfaces, including those adjacent to bolt heads, nuts, and washers, shall be free from loose scale, burrs, dirt, and foreign material that would prevent the solid seating of the parts. The faying surfaces of connections designed in accordance with Clause shall be prepared as follows: (a) (b) (c) For clean mill scale, the surfaces shall be free from oil, paint, lacquer, or any other coating in all areas within the bolt pattern and for a distance beyond the edge of the bolt hole that is the greater of 25 mm or the bolt diameter. For Classes A and B (see Table 10.9), the surfaces shall have the same blast cleaning and coating application as was used in the tests to determine the mean slip coefficient. Coated joints shall not be assembled before the coating has cured for the minimum time used in the tests to determine the mean slip coefficient. For Class C (see Table 10.9), the surfaces shall be hot-dip galvanized in accordance with CAN/CSA-G164 and subsequently roughened by hand wire-brushing. Power wire-brushing shall not be used Installation of bolts Pretensioned bolts shall be tightened in accordance with Clause to at least 70% of the minimum tensile strength specified in the applicable ASTM Standard Hardened washers The following requirements shall apply to hardened washers: (a) Hardened washers shall be provided as follows under the element turned (head or nut) during installation: (i) as required by Clause ; and (ii) for ASTM A 490/A 490M bolts. (b) Hardened washers shall also be required (i) for oversize or slotted holes that meet the requirements of Clause ; (ii) under the head and nut of ASTM A 490/A 490M bolts when used with steel with a specified minimum yield strength of less than 280 MPa; and (iii) when ASTM A 490/A 490M bolts of greater than 26 mm diameter are used in oversize or slotted holes. The washers in this case shall have a minimum thickness of 8 mm. 524 (Replaces p. 524, November 2006)

50 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Bevelled washers Bevelled washers shall be used to compensate for lack of parallelism where, in the case of ASTM A 325/A 325M bolts, an outer face of bolted parts has more than a 5% slope with respect to a plane normal to the bolt axis. In the case of ASTM A 490/A 490M bolts, bevelled washers shall be used to compensate for any lack of parallelism due to the slope of outer faces Turn-of-nut tightening After the holes in a joint are aligned, a sufficient number of bolts shall be placed and brought to a snug-tight condition to ensure that the parts of the joint are brought into full contact with each other. Following the initial snugging operation, bolts shall be placed in any remaining open holes and brought to snug-tightness. Resnugging can be necessary in large joints. When all bolts are snug-tight, each bolt in the joint shall be further tightened by the applicable amount of relative rotation specified in Table 10.18, with tightening progressing systematically from the most rigid part of the joint to its free edges. During this operation, there shall be no rotation of the part not turned by the wrench unless the bolt and nut are match-marked to enable the amount of relative rotation to be determined. Table Nut rotation from snug-tight condition* (See Clauses and ) Disposition of outer faces of bolted parts Bolt length Turn from snug Both faces normal to the bolt axis or one face normal to the axis and the other sloped 1:20 (bevelled washers not used) Both faces sloped 1:20 from normal to the bolt axis (bevelled washers not used) Up to and including four diameters 1/3 Over four diameters and not exceeding eight diameters or 200 mm 1/2 Exceeding eight diameters or 200 mm 2/3 All lengths 3/4 *Nut rotation is rotation relative to a bolt regardless of whether the nut or bolt is turned. The tolerance on rotation is 30 over. This Table applies to coarse-thread, heavy-hex structural bolts of all sizes and lengths used with heavy-hex semi-finished nuts. Bolt length is measured from the underside of the head to the extreme end point. Bevelled washers are necessary when ASTM A 490/A 490M bolts are used Inspection An inspector shall determine whether the requirements of Clauses and to have been met. Installation of bolts shall be observed to ascertain that a proper tightening procedure is employed. The turned element of all bolts shall be visually examined for evidence that they have been tightened. When properly installed, the tip of the bolt shall be flush with or outside the face of the nut. Tensions in bolts installed by the turn-of-nut method exceeding those specified in Clause shall not be cause for rejection. When there is disagreement concerning the results of an inspection of bolt tension, the following arbitration procedure shall be used unless a different procedure has been specified: (a) The inspector shall use an inspection wrench that is a manual or power torque wrench capable of indicating a selected torque value. (b) Three bolts of the same grade and diameter as those under inspection and representative of the lengths and conditions of those in the bridge shall be placed individually in a calibration device capable of measuring bolt tension. There shall be a washer under the part turned if washers are so used in the bridge or, if no washer is used, the material abutting the part turned shall be of the same specification as that in the bridge. (Replaces p. 525, November 2006) 525

51 S6S1-10 (c) (d) (e) When the inspection wrench is a manual wrench, each bolt specified in Item (b) shall be tightened in the calibration device by any convenient means to an initial tension of approximately 15% of the required fastener tension, and then to the minimum tension specified for its size in Clause Tightening beyond the initial condition shall not produce greater nut rotation beyond that permitted by Table The inspection wrench shall then be applied to the tightened bolt and the average torque necessary to turn the nut or head 5 in the tightening direction shall be determined. The average torque measured in these tests of three bolts shall be taken as the job inspection torque to be used in the manner specified in Item (e). The job inspection torque shall be established at least once each working day. When the inspection wrench is a power wrench, it shall first be applied to produce an initial tension of approximately 15% of the required fastener tension and then adjusted so that it will tighten each bolt specified in Item (b) to a tension of at least 5% but not more than 10% greater than the minimum bolt tension specified for its size in Clause This setting of the wrench shall be taken as the job inspection torque to be used in the manner specified in Item (e). Tightening beyond the initial condition shall not produce greater nut rotation than that permitted by Table The job inspection torque shall be established at least once each working day. Bolts represented by the sample specified in Item (b) that have been tightened in the bridge shall be inspected by applying, in the tightening direction, the inspection wrench and its job inspection torque to 10% of the bolts (but not fewer than two bolts) selected at random in each connection. If no nut or bolt head is turned by this application of the job inspection torque, the connection shall be accepted as being properly tightened. If any nut or bolt head is turned by the application of the job inspection torque, this torque shall be applied to all of the bolts in the connection, and all of the bolts whose nut or head is turned by the job inspection torque shall be retightened and reinspected. Alternatively, the fabricator or erector, at his or her option, may retighten all of the bolts in the connection and then resubmit the connection for inspection Reuse of bolts ASTM A 490/A 490M and galvanized ASTM A 325/A 325M bolts shall not be reused once they have been fully tightened. Other ASTM A 325/A 325M bolts may be reused up to two times, provided that proper control on the number of reuses can be established. Touch-up of pretensioned bolts in a multi-bolt joint shall not constitute a reuse unless a bolt becomes substantially unloaded as other parts of the joint are bolted Shop trial assembly Girders and other main components shall be preassembled in the shop in order to prepare or verify the field-splices. Components shall be supported in a manner consistent with the finished geometry of the bridge, as specified on the Plans, with allowance for any camber required to offset the effects of dead load deflection. Holes in the webs and flanges of main components shall be reamed or drilled to final size while in assembly. The components shall be pinned and firmly drawn together by bolts before reaming or drilling. Drifting done during assembly shall be sufficient only to align the holes and not to distort the steel. If necessary, reaming shall be used to enlarge holes. When a number of sequential assemblies are necessary because of the length of the bridge, the second and subsequent assemblies shall include at least one section from the preceding assembly to provide continuity of alignment. Trial assemblies shall be required whether the field-splices are bolted or welded. Each assembly shall be checked for camber, alignment, accuracy of holes, and fit-up of welded joints and milled surfaces. Corrective work, if necessary, shall be carried out at no cost to the Owner Holes drilled using numerically controlled machines As an alternative to the trial assembly specified in Clause when the bolt holes have been prepared by numerically controlled drilling or using a suitable template, the accuracy of the drilling may be demonstrated by a check assembly consisting of the first components of each type to be made. If the check assembly is satisfactory, further assemblies of like components shall not be required. 526 (Replaces p. 526, November 2006)

52 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code If the check assembly is unsatisfactory for any reason, the work shall be redone or repaired in a manner acceptable to the Owner. Further check assemblies shall be required, as specified by the Owner, to demonstrate that the required accuracy of fit-up has been achieved Match-marking Connecting parts that are assembled in the shop for reaming or drilling holes shall be match-marked. A drawing shall be prepared to show how the marked pieces should be assembled in the field to replicate the shop assembly Tolerances Structural members Structural members consisting of a single rolled shape shall meet the straightness tolerances of CSA G40.20, except that columns shall not deviate from straight by more than 1/1000 of the length between points of lateral support. A variation of 1 mm from the detailed length shall be permissible in the length of members that have both ends finished for contact bearing. Other members without finished ends may have a variation from the detailed length of not more than 2 mm for members 10 m or less in length, and not more than 4 mm for members over 10 m in length Abutting joints When compression members are butted together to transmit loads in bearing, the contact faces shall be milled or saw-cut. The completed joint shall have at least 75% of the entire contact area in full bearing, defined as not more than 0.5 mm separation, and the separation of the remainder shall not exceed 1 mm. At joints where loads are not transferred in bearing, the nominal dimension of the gap between main members shall not exceed 10 mm, with a tolerance of ±5 mm from the nominal dimension Facing of bearing surfaces The surface finish of bearing surfaces that are in contact with each other or with concrete shall meet the roughness requirements specified in CSA B95 and Table Surfaces of flanges that are in contact with bearing sole plates shall be flat within 0.5 mm over an area equal to the projected area of the bearing stiffeners and web. Outside this area, a 2 mm deviation from flat shall be acceptable. The bearing surface shall be perpendicular to the web and bearing stiffeners. Table Facing of bearing surfaces roughness requirements (See Clause ) Surface roughness Contact surfaces Steel slabs or plates in contact with concrete Plates in contact as part of bearing assemblies Milled ends of compression members Milled or ground ends of stiffeners Bridge rollers or rockers Pins and pin holes Sliding bearings Steel/copper alloy or steel/stainless steel Micro-inches Microns (Replaces p. 527, November 2006) 527

53 S6S Bearing plates Bearing plates shall meet the following requirements: (a) rolled steel bearing plates 50 mm or less in thickness may be used without planing if a satisfactory contact bearing is obtained; (b) rolled steel bearing plates more than 50 mm thick but not more than 100 mm thick may be straightened by pressing or by planing on all bearing surfaces to obtain a satisfactory contact bearing; and (c) rolled steel bearing plates more than 100 mm thick shall be planed on all bearing surfaces, except for those surfaces that are in contact with concrete foundations and are grouted to ensure full bearing Fabricated components The tolerances for welded components shall comply with Clause 5.4 of CSA W59. The dimensional tolerances of welded structural members shall be those specified in Clauses 5.8 and of CSA W59. Built-up, bolted structural members shall comply with the straightness tolerances specified in CSA G40.20 for rolled wide-flanged shapes. Bearing stiffeners fitted to bear shall have a minimum bearing contact area of 75% and a maximum separation of 1 mm over the remaining area. Fitted intermediate stiffeners shall have a minimum bearing contact area of 25% and a maximum separation of 2 mm Quality control Qualification of inspectors Welding inspectors shall be qualified by the CWB to the requirements of CSA W Non-destructive testing of welds At least the following non-destructive testing of welds shall be performed: (a) visual inspection of all welds; (b) radiographic or ultrasonic inspection of groove welds in flanges and webs of built-up girders, as follows: (i) flange splices in tension or stress reversal zones: 100%; (ii) flange splices in compression zones: 25%; and (iii) web splices: 100% for one-half of the depth from the tension flange and 25% for the remainder of the web; (c) magnetic particle inspection of web-to-flange fillet welds, as follows: (i) submerged-arc welds: 25%; (ii) semi-automatic welds: 50%; and (iii) manual welds: 100%; and (d) magnetic particle inspection of fillet welds, as follows, for connection plates and stiffeners to which cross-bracing or diaphragms are attached: (i) for one-half of the depth from the tension flange: 100%; and (ii) transverse welds on tension flanges: 100%. Radiographic and ultrasonic testing shall be performed before assembly of the flanges to the webs Acceptance standards for weld defects The acceptance standards for dynamically loaded structures specified in Clause of CSA W59 shall apply to weld defects Repair of welds Welds that do not meet the acceptance standards specified in Clause shall be removed, rewelded, and retested. Repairs and non-destructive testing of fracture-critical and primary-tension members shall be performed in accordance with Clause (Replaces p. 528, November 2006)

54 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Identification of structural steel In the fabricator s plant, the specification and grade of steel used for main components shall be identified by use of suitable markings or recognized colour coding. Cut pieces that are identified by piece mark and contract number need not continue to carry specification identification markings when it has been established that such pieces conform to the required material specifications. Records shall be kept to identify the heat number of the material and the corresponding mill test report for each component of a fracture-critical or primary tension member Transportation and delivery Structural steel shall be loaded for shipping, transported, unloaded, and stored clear of the ground at its destination without being excessively stressed, deformed, or otherwise damaged. Where possible, plate girders shall be transported with their webs in the vertical plane. Where girders cannot be shipped with their webs in the vertical plane, static and dynamic forces during handling, transport, and storage shall be determined using a dynamic load allowance of at least 100%, unless a lower value can be justified. Computed stresses shall satisfy the provisions of Clause Fatigue stresses due to dynamic flexure during transport shall also be considered Erection Erection conditions Components shall be lifted and placed using appropriate lifting equipment, temporary bracing, guys, or stiffening devices so that they are not overloaded or unstable. Additional permanent material may be provided, if Approved, to ensure that the member capacities are not exceeded during erection Falsework All falsework, including necessary foundations, required for the safe construction of a bridge shall be designed, furnished, maintained, and removed by the contractor. The contractor shall not use any of the material intended for use in the finished bridge for temporary purposes during erection, unless such use is Approved Removal of temporary bracing or guys Temporary bracing or guys shall be removed when no longer required for the stability of the bridge, unless otherwise Approved Maintaining alignment and camber The bridge shall be erected to the proper alignment on plan and in elevation, taking into account the specified dead load camber Field assembly Parts shall be assembled following the piece marks shown on the erection drawings and match-marks. Main girder splices and field connections shall have half their holes filled with fitting-up bolts and drift-pins (half bolts and half pins) before the installing and tightening of the balance of the connection bolts. The fitting-up bolts may be the same high-strength bolts used in the installation. The pins shall be 1 mm larger in diameter than the bolts. Excessive drifting that distorts the metal and enlarges the holes shall not be allowed, although reaming up to 2 mm over the nominal hole diameter shall be permitted, except for oversize or slotted holes Cantilever erection When cantilever erection is used, splices that support the cantilevering member shall be fully bolted before the cantilever is further extended or loaded. (Replaces p. 529, November 2006) 529

55 S6S Repairs to erected material With the exception of splices of main material, the correction of minor misfits involving minor amounts of reaming, cutting, and shimming shall be permitted. The correction of other shop fabrication, or any deformation resulting from handling or transportation that prevents the proper assembly and fitting of the parts, shall require Approval Field welding Any company undertaking field welding in accordance with this Section shall be certified to Division 1 or 2 of CSA W Attachments Tack welds intended to be used for attachments or for any other purpose shall not be used unless they subsequently become a part of the welds shown on the Plans. Tack welds that are not part of the welds shown on the Plans shall not be used on any portion of the girders Protection of the substructure against staining The substructure shall be protected against rust staining by water runoff from the bridge, as specified on the Plans. 530 (Replaces p. 530, November 2006)

56 Hydraulic cylinder connections Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The loads on the structural connections to the cylinders shall be based on the maximum of (a) wind, ice, inertia, or other structural loads, assuming the cylinder as a rigid link; and (b) driving and braking mechanical loads, assuming a cylinder force developed by 150% of the setting of the pressure-relief valve that controls the maximum pressure available at the cylinder Loads on end floor beams and stringer brackets The end floor beams and stringer brackets of the moving span shall be proportioned for at least the factored dead load and factored live load plus twice the factored dynamic load allowance Swing bridges Ultimate limit states Closed position In the closed position, the bridge ends are lifted to give a positive reaction equal to 150% of the maximum negative reaction due to live load and dynamic load allowance. For this position, load combinations ULS 1 to ULS 8 of Section 3 shall apply Special load combinations and load factors In addition to load combinations ULS 1 to ULS 8 of Section 3, the special load combinations and load factors specified in Table 13.3 shall be considered. Table 13.3 Swing bridges Special load combinations and load factors (See Clauses and ) Load combination D o * L s L c W o I o M o ULS S1 ULS S2 ULS S3 ULS S4 ULS S5 ULS S6 ULS S7 D D D D D D D *See Table 13.6 for values of D. Notes: (1) When the ends are being lifted, the loading combination and load factors are similar to ULS S1 except that there are different machinery forces and there are forces at the ends. (2) For any combination, the minimum or maximum value of the load factor, D, shall be used so as to maximize the total force effect. Legend: D o = dead load; bridge open in any position or closed with ends just touching L s = live load (including dynamic load allowance) on one arm as a simple span; bridge closed with ends just touching L c = live load (including dynamic load allowance); bridge closed with ends just touching, with bridge considered as a continuous structure; reactions at both ends to be positive W o = wind load; bridge open in any position or closed with ends just touching I o = operating impact of 20% applied to the maximum dead load effect in all members that are in motion and to the load effect on a stationary member caused by the moving dead load M o = maximum forces on structural parts caused by the operation of machinery, or by forces applied for moving or stopping the span, increased 100% as an allowance for impact (Replaces p. 591, November 2006) 591

57 S6S Stationary in open position In the event that a movable bridge is required to remain open or can be stuck in the open position, the requirements of Section 3 for wind loads on a fixed bridge shall apply Bascule (including rolling lift) bridges Ultimate limit states Closed position When the bridge is not in operating mode and the counterweight is not temporarily supported for repairs, load combinations ULS 1 to ULS 8 of Section 3 shall apply Special load combinations and load factors In addition to load combinations ULS 1 to ULS 8 of Section 3, the special load combinations and load factors specified in Table 13.4 shall be considered. Table 13.4 Bascule (including rolling lift) bridges Special load combinations and load factors (See Clauses and ) Load combination D o * D t * L t H o W o I o M o ULS B1 ULS B2 ULS B3 ULS B4 ULS B5 D D D D D *See Table 13.6 for values of D. Notes: (1) Combination ULS B4 applies only to those parts of the structure that support trunnions of the moving span and/or counterweight. (2) For any combination, the minimum or maximum value of the dead load factor, D, specified in Section 3 shall be used to maximize the total force effects. Legend: D o = dead load; bridge open in any position or closed with ends just touching D t = dead load; bridge closed; counterweight supported for repairs L t = live load (including dynamic load allowance); bridge closed; counterweight supported for repairs H o = horizontal force, taken as 5% of the total moving load carried by the steel towers and/or special parts of the structure that support the counterweight assembly; bridge open in any position; this force shall be applied in any direction, through the centre of gravity of the moving load W o = wind load; bridge open in any position or closed with ends just touching I o = operating impact of 20% applied to the maximum dead load effect in all members that are in motion and to the load effect on a stationary member caused by the moving dead load M o = maximum forces on structural parts caused by the operation of machinery, or by forces applied for moving or stopping the span, increased 100% as an allowance for impact 592 (Replaces p. 592, November 2006)

58 Vertical lift bridges Ultimate limit states Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Closed position When the bridge is not in operating mode and the counterweight is not temporarily supported for repairs, load combinations ULS 1 to ULS 8 of Section 3 shall apply Special load combinations and load factors In addition to load combinations ULS 1 to ULS 8 of Section 3, the special load combinations and load factors specified in Table 13.5 shall be considered. Table 13.5 Vertical lift bridges Special load combinations and load factors (See Clauses and ) Load combination D o * D t * L t W o I o M o ULS V1 ULS V2 ULS V3 ULS V4 D D D D *See Table 13.6 for values of D. Note: For any combination, the minimum or maximum value of the dead load factor, D, shall be used to maximize the total force effects. Legend: D o = dead load; bridge open in any position or closed with ends just touching D t = dead load; bridge closed; counterweight supported for repairs L t = live load (including dynamic load allowance); bridge closed; counterweight supported for repairs W o = wind load; bridge open in any position or closed with ends just touching I o = operating impact of 20% applied to the maximum dead load effect in all members that are in motion and to the load effect on a stationary member caused by the moving dead load M o = maximum forces on structural parts caused by the operation of machinery, or by forces applied for moving or stopping the span, increased 100% as an allowance for impact Dead load factor The dead load factor, D, in Tables 13.3 to 13.5 shall be as specified in Table Table 13.6 Dead load factor, D (See Clause and Tables ) Dead load type Maximum Minimum D1 Factory-produced components D2 Cast-in-place concrete and wood D3 Wearing surface (Replaces p. 593, November 2006) 593

59 S6S All movable bridges Ultimate limit states Longitudinal wind shall be included in the design of the superstructure for load combinations ULS 3, ULS 4, and ULS 7 of Section 3. For seismic loading with the bridge open, load combination ULS 5 of Section 3, as modified by Clause , shall apply. For vessel collisions with the bridge operating, load combination ULS 8 of Section 3 shall apply Special types of movable bridges The analysis of special types of movable bridges shall be carried out for all applicable load conditions. The members shall be proportioned for total factored load effects in accordance with the requirements specified in this Section for the design of fixed, swing, bascule, and vertical lift bridges Load effects A drawing shall be prepared showing the load effects for the various analyses and the total factored load effects for the applicable combinations in the different primary members at appropriate locations Fatigue limit state The stress range arising from the operation of the span from the fully closed to the fully open position and back to the fully closed position, including the effect of wind, shall be less than the allowable stress range specified in Section 10, based on the estimated number of load cycles. This Clause shall also apply to members and/or steel that are embedded in or encase counterweights and either support the mass or transfer the load to the main structure, and to the connections of such members Friction Consideration shall be given to bending stresses arising from pin, journal, trunnion, and other friction Machinery supports All structural parts supporting machinery shall be of ample strength and rigidity and be designed to minimize vibration Vertical lift bridge towers The lateral bracing of vertical lift bridge towers shall be designed for 2.5% of the total compression in the columns in addition to the specified wind loads Transitory loads Transitory loads, e.g., operating impact, shall be included in the loading combinations only if their inclusion increases the total factored load effect Mechanical system design General Because mechanical system design in North America is based mainly on working stress design, the requirements of Clauses to are specified in terms of working stress even though other clauses of this Code are based on limit states design. Most North American textbooks on mechanical system design use foot/pound units. Accordingly, where a value was originally expressed in foot/pound units, Clause 13.8 provides the foot/pound value in parentheses, accompanied by a soft-converted SI value. 594 (Replaces p. 594, November 2006)

60 Section 14 Evaluation 14.1 Scope Definitions Symbols General requirements Exclusions Expertise Future growth of traffic or future deterioration Scope of evaluation Evaluation procedures General Limit states Deleted Evaluation methodology Bridge posting Condition inspection General Plans Physical features Deterioration Material strengths General Review of original construction documents Analysis of tests of samples Strengths based on date of construction Deteriorated material Permanent loads General Dead load Earth pressure and hydrostatic pressure Shrinkage, creep, differential settlement, and bearing friction Secondary effects from prestressing Transitory loads Normal traffic Permit Vehicle loads Dynamic load allowance for permit vehicle loads and alternative loading Multiple-lane loading Loads other than traffic Exceptional loads Lateral distribution categories for live load General Statically determinate method Sophisticated method Simplified method Target reliability index General System behaviour Element behaviour Inspection level Important structures Load factors General 661 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code (Replaces p. 641, November 2006) 641

61 S6S Permanent loads Transitory loads Resistance General Resistance adjustment factor Effects of defects and deterioration Live load capacity factor General Ultimate limit states Serviceability limit states Combined load effects Load testing General Instrumentation Test load Application of load test results Bridge posting General Calculation of posting loads Posting signs Fatigue 679 Annexes A14.1 (normative) Equivalent material strengths from tests of samples 680 A14.2 (normative) Evaluation Level 1 (vehicle trains) in Ontario 682 A14.3 (normative) Evaluation Level 2 (two-unit vehicles) in Ontario 683 A14.4 (normative) Evaluation Level 3 (single-unit vehicles) in Ontario (Replaces p. 642, November 2006)

62 P = posting factor P n = unfactored resistance of a masonry arch, kn P r = factored resistance of a masonry arch, kn Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code q = average percentage of tensile reinforcement in the two directions in which steel is placed at the midspan of a slab panel (see Clause ); uniformly distributed portion of lane load, kn/m R = nominal unfactored resistance, kn, calculated using the material strengths as specified in Clause and in accordance with the requirements of Sections 6 to 12 and Clause (see Clause ) R = mean resistance, kn REL 1 = loss of prestress due to relaxation of prestressing steel prior to transfer, MPa REL 2 = loss of prestress due to relaxation of prestressing steel after transfer, MPa R d = nominal resistance of a concrete deck slab, kn R n = unfactored (nominal) resistance of a concrete deck slab, kn R r = factored resistance of structural component, kn S D = standard deviation of dead load force effects S L = standard deviation of live load force effects SH = loss of prestress due to shrinkage of concrete, MPa s = spacing of stirrups measured parallel to the longitudinal axis of a component, mm s m1 = maximum allowable spacing below which a section is considered to have full transverse reinforcement, mm s m2 = maximum allowable spacing above which a section is considered not to have transverse reinforcement, mm s r1 = maximum allowable spacing, as a fraction of shear depth, below which the section is considered to have transverse reinforcement s r2 = maximum allowable spacing, as a fraction of shear depth, above which the section is considered not to have transverse reinforcement T f = tensile force in a member or component at the ultimate limit state, N T r = factored tensile resistance of a riveted joint, N t = thickness of a steel component, mm; thickness of a concrete deck slab, mm; time, d U = resistance adjustment factor V = coefficient of variation V AD = coefficient of variation for dead load analysis method V AL = coefficient of variation for live load analysis method V D = coefficient of variation for dead load V I = coefficient of variation for dynamic load allowance V L = coefficient of variation for live load V R = coefficient of variation for resistance V S = coefficient of variation for total load V f = shear force at the ultimate limit state, N V p = component in the direction of the applied shear of all of the effective prestressing forces crossing the critical section factored by p, the resistance factor for tendons in Clause (taken as positive if resisting the applied shear), N V r = factored shear resistance of a riveted joint, N W = gross vehicle weight, kn (Replaces p. 645, November 2006) 645

63 S6S1-10 A = load factors for force effects due to additional loads (including wind, creep, shrinkage, temperature, and differential settlement) that may be considered in the evaluation D = load factors for force effects due to dead loads L = load factors for force effects due to live loads = target reliability index AD = bias coefficients (ratio of mean to nominal effects) for dead load analysis method AL = bias coefficients (ratio of mean to nominal effects) for live load analysis method D = bias coefficients (ratio of mean to nominal effects) for dead load I = bias coefficients (ratio of mean to nominal effects) for dynamic load allowance L = bias coefficients (ratio of mean to nominal effects) for live load R = bias coefficients (ratio of mean to nominal effects) for resistance µ p = ratio of area of prestressed reinforcement to area of concrete = reinforcement ratio of tensile reinforcement b = reinforcement ratio producing balanced conditions when the tension reinforcement reaches its yield strain just as the concrete compression reaches a strain of used in the calculation of U A = unfactored stress due to additional loads (including wind, creep, shrinkage, temperature, and differential settlement) that may be considered in the evaluation, MPa D = unfactored dead load stress, MPa L = unfactored live load stress, MPa SLS = serviceability limit state stress, MPa = resistance factor c = resistance factor for concrete (see Clause 8.4.6) mc = member resistance factor for a riveted connection md = member resistance factor for a reinforced concrete deck slab mm = member resistance factor for a masonry component r = material resistance factor for rivet steel p = mechanical reinforcement ratio for prestressing steel 14.4 General requirements Exclusions This Section shall not be used to determine whether a bridge or bridge design complies with the design requirements of Sections 1 to 13 and 16. Pedestrian bridges, railings, barrier walls, foundations, and retaining walls shall be evaluated in accordance with the design requirements of this Code. This Section does not address loads caused by earthquakes, fires, floods, ice, and vehicle and vessel collisions. This Section shall not be used unless the bridge is secure against causes of failure other than traffic loading. Loads other than traffic shall be considered in accordance with other Sections of this Code, except as required by Clause This Section shall not be used for buried structures Expertise Evaluations in accordance with this Section shall be performed and checked by suitably qualified Engineers, and shall be reviewed by an experienced bridge Engineer, who may also be one of the persons performing or checking the evaluation. 646 (Replaces p. 646, November 2006)

64 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Future growth of traffic or future deterioration No allowance is made in this Section for future growth of traffic or for future deterioration of the bridge. If such changes are anticipated, they shall be considered in the evaluation. If any change in traffic or in the condition of the bridge that has not been accounted for occurs, the evaluation shall be reviewed and, if necessary, the bridge shall be re-evaluated Scope of evaluation The scope of the evaluation shall be determined in consultation with the Owner, with particular care exercised for single load path structures with brittle failure modes Evaluation procedures General The procedures in this Section shall be used when bridges are to be evaluated for load limit restrictions, serviceability, or fatigue loadings. A bridge shall be evaluated in accordance with one or more of the following methods: (a) ultimate limit states methods (except for masonry abutments, masonry piers, and masonry retaining walls). The following shall be considered acceptable methods: (i) ultimate limit states methods in accordance with Clauses and , using load and resistance adjustment factors specified in Clauses and 14.14; (ii) the mean load method for ultimate limit states specified in Clause ; and (iii) the load testing method specified in Clause 14.16; (b) serviceability limit states methods; and (c) other Approved methods Limit states General The limit states for which a bridge is to be evaluated shall be selected from Clauses to Ultimate limit states Ultimate limit states shall be used in determining the load-carrying capacity, stability, and load posting of bridges, except as specified in Clause Serviceability limit states Serviceability limit states shall be used in determining the load-carrying capacity, stability, and load posting of masonry abutments, masonry piers, and masonry retaining walls, in accordance with Clause For a bridge where cracking, deformation, stresses, or vibrations are detrimental to the structure, expected, or evident, the bridge and its affected components shall be evaluated for serviceability limit states requirements in accordance with the applicable Sections of this Code. Where there is no evidence of serviceability-related defects, the evaluation need not consider the serviceability limit state if neither the use nor the behaviour of the bridge is changed Fatigue limit state Evaluations for the fatigue limit state shall be carried out in accordance with Clause (Replaces p. 647, November 2006) 647

65 S6S Deleted Deleted Evaluation methodology General The following requirements shall apply to the evaluation of bridges in accordance with this Section: (a) a condition inspection of the structure shall be conducted in accordance with Clause 14.6; (b) material strengths shall be determined in accordance with Clause 14.7; (c) loads shall be defined in accordance with Clauses 14.8 to 14.10; and (d) lateral distribution of live load shall be categorized in accordance with Clause Evaluation at ultimate limit states using load and resistance factors The following requirements shall apply to the evaluation at ultimate limit states using load and resistance factors: (a) the target reliability index,, shall be selected in accordance with Clause ; (b) the load factors shall be selected in accordance with Clause 14.13; (c) the resistances shall be calculated in accordance with Clause 14.14; and (d) the live load capacity factor, F, shall be determined in accordance with Clause Evaluation at serviceability limit states For evaluation at serviceability limit states, the live load capacity factor, F, shall be determined in accordance with Clause Evaluation by use of mean load method The following requirements shall apply to evaluation by use of the mean load method: (a) the target reliability index,, shall be selected in accordance with Clause ; (b) nominal (unfactored) resistances shall be calculated in accordance with Sections 6 to 12 or Clause by taking all resistance factors,, as having a value of 1.0; and (c) the live load capacity factor, F, shall be determined in accordance with Clause Evaluation by load testing The following requirements shall apply to evaluation by load testing: (a) the bridge shall be evaluated in accordance with Clause , , or ; (b) the bridge shall be tested in accordance with Clause 14.16; and (c) the live load capacity factor, F, shall be determined in accordance with Clause Bridge posting If a bridge needs to be posted for load restriction based on the load capacity factor calculated in accordance with Clause or 14.16, the posting loads shall be in accordance with Clause Condition inspection General A condition inspection of the bridge shall be carried out to the satisfaction of the evaluator. Inspection records shall be sufficiently detailed to allow changes in condition to be assessed during future inspections. 648 (Replaces p. 648, November 2006)

66 Plans Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The evaluator shall verify that the available Plans accurately represent the dimensions, member sizes, and other essential geometric features of the structure, for the original construction and subsequent rehabilitations and modifications. If no Plans are available, measurements shall be made with sufficient precision to suit the intended purpose Physical features All physical features of a bridge that affect its structural integrity shall be examined Deterioration All flawed, damaged, distorted, or deteriorated regions shall be identified, and sufficient data shall be collected so that these defects can be properly considered in the evaluation Material strengths General The strengths of materials that do not have visible signs of deterioration shall be determined using one of the following methods: (a) review of Plans and other documents in accordance with Clause ; (b) analysis of tests of samples obtained from the bridge or from specific bridge components in accordance with Clause ; (c) estimation by considering the date of bridge construction in accordance with Clause ; or (d) an Approved method Review of original construction documents General The Plans and other relevant contract documents may be reviewed to determine (a) the specified minimum yield strength of structural steel; (b) the specified compressive strength of concrete; (c) the specified minimum yield strength of reinforcing steel; (d) the specified tensile strength of prestressing steel; (e) the species and grade of wood; and (f) the type of stone and grade of mortar used in masonry construction Mill certificates Actual values of yield and ultimate tensile stresses reported on mill certificates shall not be used for evaluation. Instead, the strength used shall be the guaranteed minimum value specified for the grade of steel shown on the certificate Analysis of tests of samples General Nominal material strengths to be used in the calculation of member resistances may be determined by testing samples obtained from the bridge. Samples shall not be removed from locations where the strength, stability, or integrity of the member might be adversely affected. The location and orientation of each sample shall be recorded, as well as any additional information that could later be useful in interpretation of the test results. (Replaces p. 649, November 2006) 649

67 S6S1-10 Material strength values obtained by testing shall not be directly substituted into the equations for resistance specified in this Code. Test results shall be converted to nominal material strengths in accordance with Annex A14.1 or an Approved method Prestressing steel Removal of prestressing steel specimens for testing shall not jeopardize the safety of the structure or be hazardous to the personnel involved. Specimens shall be tested in accordance with CSA G Wood In lieu of obtaining wood samples for testing, the species and grade shall be identified by a wood grader Masonry mortar Mortar in joints shall be sampled or tested to obtain the compressive strength. The mortar shall be classified as one of the following types: (a) hard mortar compressive strength greater than 7 MPa; (b) medium mortar compressive strength between 2 and 7 MPa; or (c) soft mortar compressive strength less than 2 MPa. The allowable limit state stress at the serviceability limit state in shear and compression shall be determined using a rational method based on the classification of the mortar, the thickness of the mortar joint, and the type of stone used in the masonry Strengths based on date of construction General In the absence of more specific information, preliminary evaluation may be based on material strengths estimated by considering the date of bridge construction Structural steel If Plans and mill certificates are not available, and coupons have not been taken for testing, the values specified in Table 14.1 shall be used for structural steel. Table 14.1 Properties of structural steel (See Clause ) Date of bridge construction Before After 1975 Specified F y, MPa Specified F u, MPa Concrete If Plans and specifications are not available and cores have not been obtained, the compressive strength of concrete with no visible signs of deterioration shall be taken as 15 MPa for the substructure, 20 MPa for the superstructure, and 25 MPa for prestressed concrete components Reinforcing steel If Plans and mill certificates are not available and specimens have not been tested, the values specified in Table 14.2 shall be used for reinforcing steel. 650 (Replaces p. 650, November 2006)

68 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Table 14.2 Minimum yield strengths of reinforcing steel, MPa (See Clause ) Date of bridge construction Before After 1978 Grade Structural Medium or intermediate Hard Unknown Prestressing steel If Plans and mill certificates are not available and specimens have not been tested, the tensile strength of prestressing steel shall be taken as 1600 MPa for bridges constructed before 1963 and 1725 MPa for bridges constructed later Rivets If Plans and mill certificates are not available, the following values for the ultimate tensile strength of rivets shall be used: (a) rivets constructed to ASTM A 7-39, constructed before 1936, or of unknown origin: F u = 320 MPa; and (b) rivets constructed to CESA S , CSA G , ASTM A , ASTM A , or ASTM A , or constructed after 1935 but of unknown origin: F u = 360 MPa Deteriorated material Deteriorated material shall be assessed in accordance with Clause Non-destructive test methods, such as ultrasonic pulse velocity and surface hardness methods, may be used to correlate the concrete strength in damaged and sound regions of a structure. If compressive strengths are estimated using non-destructive methods, calibration factors shall be determined using concrete cores from the structure, and their uncertainty shall be accounted for in the estimate of predicted strengths Permanent loads General The evaluation of the load-carrying capacity of existing bridges shall take into consideration all permanent loads except as specified in Clause Dead load General Dead load shall include the weight of all components of the bridge, fill, utilities, and other materials permanently on the bridge. Dead loads shall be determined from available Plans and verified with field measurements in accordance with Clause Dead load shall be apportioned to three categories, D1, D2, and D3, as follows: (a) D1: dead load of factory-produced components and cast-in-place concrete, excluding decks; (b) D2: cast-in-place concrete decks (including voided decks and cementitious concrete overlays), wood, field-measured bituminous surfacing, and non-structural components; and (c) D3: bituminous surfacing where the nominal thickness is assumed to be 90 mm for the evaluation. (Replaces p. 651, November 2006) 651

69 S6S Dead load distribution The transverse distribution of dead load shall be in accordance with Section Earth pressure and hydrostatic pressure Earth pressure and hydrostatic pressure shall be considered in the evaluation, treated as permanent loads, and multiplied by a load factor in accordance with Clause Shrinkage, creep, differential settlement, and bearing friction Shrinkage, creep, differential settlement, and bearing friction need not be considered in evaluation at ultimate limit states if their effects induce ductile behaviour. When their effects induce non-ductile behaviour, they shall have load factors determined in accordance with Clause Secondary effects from prestressing Secondary effects from prestressing shall be considered as permanent loads and multiplied by load factors in accordance with Clause Transitory loads Normal traffic General Bridges shall be evaluated for the following: (a) a vehicle train, a two-unit vehicle, and a single-unit vehicle, as specified in Clause , , and , respectively; or (b) alternative loading based on local traffic, as specified in Clause Truck axles and portions of uniformly distributed lane load that reduce the load effect shall be neglected Evaluation Level 1 (vehicle trains) A bridge required to carry vehicle trains in normal traffic shall be evaluated to Evaluation Level 1, for which the live load model shall be the CL1-W Truck or Lane Load shown in Figure 14.1, where W is the gross vehicle weight in kilonewtons of a vehicle train legally permitted on bridges without a permit. The value of W shall be taken as 625 unless the Regulatory Authority uses lesser or greater values of W where traffic conditions are expected to differ from the norm. In Ontario, the load used for Evaluation Level 1 shall be the CL1-625-ONT Truck Load or CL1-625-ONT Lane Load specified in Annex A Evaluation Level 2 (two-unit vehicles) A bridge shall be evaluated to Evaluation Level 2 when load restrictions are to be applied and the bridge is required to carry two-unit vehicles. The live load model shall be the CL2-W Truck or Lane Load shown in Figure 14.2, where W is as specified in Clause In Ontario, the load used for Evaluation Level 2 shall be the CL2-625-ONT Truck Load or the CL2-625-ONT Lane Load specified in Annex A Evaluation Level 3 (single-unit vehicles) A bridge shall be evaluated to Evaluation Level 3 when load restrictions are to be applied and the bridge is required to carry single-unit vehicles. The live load model shall be the CL3-W Truck or Lane Load shown in Figure 14.3, where W is as specified in Clause In Ontario, the load used for Evaluation Level 3 shall be the CL3-625-ONT Truck Load or the CL3-625-ONT Lane Load specified in Annex A (Replaces p. 652, November 2006)

70 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Permit Controlled (PC) PC traffic shall include the vehicles authorized by permit to carry an indivisible load on a specified route under supervision and specified travel conditions. The weights and spacings of the axles shall be verified by measurement. Lane load need not be considered for PC traffic if other traffic is excluded from the bridge during passage of the PC vehicle Permit Single trip (PS) PS traffic shall include vehicles authorized by permit for a single trip to carry an indivisible load, mixed with other traffic without supervision. Axle loads and the gross vehicle weight may exceed the non-permit legislated limits. For the lane carrying the PS vehicle, the load effect shall be calculated from the more severe of (a) the permit vehicle alone in the lane with dynamic load allowance, in accordance with Clause ; (b) or 85% of the permit vehicle, plus a superimposed uniformly distributed load of 9, 8, 7, and 7 kn/m for highway classes A, B, C, and D, respectively, without dynamic load allowance for either Truck or uniformly distributed loads Dynamic load allowance for permit vehicle loads and alternative loading The dynamic load allowance for permit vehicle loads shall be as specified in Clause , except the dynamic load allowance specified in Clause (c) shall be taken as 0.30 for tandems, tridems, two-axle groups, and the axle group consisting of the front axle and drive axles. For a permit vehicle crossing the bridge at a restricted speed, the dynamic load allowance so calculated shall be multiplied by (a) 0.30 for a vehicle speed of 10 km/h or less; (b) 0.50 for a vehicle speed greater than 10 km/h and less than or equal to 25 km/h; (c) 0.75 for a vehicle speed greater than 25 km/h and less than or equal to 40 km/h; and (d) 1.00 for a vehicle speed greater than 40 km/h Multiple-lane loading Design lanes The number of loaded lanes shall be determined in accordance with the current or intended use of the bridge. Where the traffic lanes are clearly designated on the bridge, they shall be used as design lanes, except that outer lanes shall include the adjacent shoulders Normal traffic The modification factors for multiple-lane loading shall be as specified in Table (Replaces p. 657, November 2006) 657

71 S6S1-10 Table 14.3 Modification factors for multiple-lane loading (See Clause ) Number of lanes loaded or more Highway class A B C r D o Permit vehicle with normal traffic When the permit vehicle is allowed to travel with normal traffic, the loading to be applied in the other lanes shall be taken as a fraction of the CL1-W loading or CL1-625-ONT loading, as specified in Table Table 14.4 Fraction of CL1-W loading to be applied in the other lanes (See Clause ) Highway class A B C r D o Second loaded lane Third and subsequent loaded lanes Loads other than traffic Sidewalk loading Except for sidewalk components, sidewalk loading shall not be considered coincident with traffic loading unless the evaluator has reason to suppose that significant sidewalk loading will occur coincident with maximum traffic loading, in which case the pedestrian loading specified in Clause shall be used with the same load factor specified in Clause for traffic Snow loads If significant snow loading on sidewalks is expected, it shall be considered in the evaluation Wind loads Wind loads are not specifically considered in this Section. If the evaluator considers that significant wind forces could occur simultaneously with the maximum traffic loads, these wind forces shall be considered in accordance with Clause Temperature effects Temperature effects need not be considered at ultimate limit states for any element that will behave in a ductile manner. When non-ductile behaviour is expected, temperature effects shall be considered in accordance with Clause (Replaces p. 658, November 2006)

72 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Secondary effects Secondary effects (excluding secondary effects from prestressing) need not be considered in evaluation at ultimate limit states if their effects induce ductile behaviour. When secondary effects induce non-ductile behaviour, they shall be considered and multiplied by a load factor in accordance with Clause Deleted Exceptional loads Loads (other than traffic loads) that occur on rare occasions and are of significant magnitude shall be considered exceptional loads and shall be evaluated in accordance with Sections 1 to 13 and 16 or, when not covered by Sections 1 to 13 and 16, in accordance with good engineering practice Lateral distribution categories for live load General The method to be used in calculating the lateral distribution of live loads to the elements considered shall be categorized as statically determinate, sophisticated, or simplified in accordance with Clauses to Statically determinate method In this method the lateral distribution is statically determinate Sophisticated method In this method the lateral distribution is statically indeterminate and is calculated in accordance with a sophisticated method of analysis such as the grillage analogy, orthotropic plate theory, finite element, finite strip, or folded plate method Simplified method In this method the lateral distribution is calculated in accordance with the simplified methods of Section 5. However, it is possible that the methods specified in Section 5 will not be suitable for non-standard bridges or permit vehicle loads (especially those that are wider than the CL-W vehicles), in which cases such methods shall not be used Target reliability index General For all evaluation levels, the target reliability index,, shall be taken from Table 14.5 for PA, PB, and PS traffic and Table 14.6 for PC traffic. In both cases, the system behaviour, element behaviour, and inspection level shall be as specified in Clauses to (Replaces p. 659, November 2006) 659

73 S6S System behaviour System behaviour shall take into consideration the effect of any existing deterioration and shall be classified into one of the following categories: (a) Category S1, where element failure leads to total collapse. This includes failure of main members with no benefit from continuity or multiple-load paths, e.g., a simply supported girder in a two-girder system. (b) (c) Category S2, where element failure probably will not lead to total collapse. This includes main load-carrying members in a multi-girder system or continuous main members in bending. Category S3, where element failure leads to local failure only. This includes deck slabs, stringers, and bearings in compression Element behaviour Element behaviour shall take into consideration the effect of any existing deterioration and shall be classified into one of the following categories: (a) Category E1, where the element being considered is subject to sudden loss of capacity with little or no warning. This can include failure by buckling, concrete in shear and/or torsion with less than the minimum reinforcement required by Clause (a), bond (pullout) failure, suspension cables, eyebars, bearing stiffeners, over-reinforced concrete beams, connections, concrete beam-column compression failure, and steel in tension at net section. (b) (c) Category E2, where the element being considered is subject to sudden failure with little or no warning but will retain post-failure capacity. This can include concrete in shear and/or torsion with at least the minimum reinforcement required by Clause (a), and steel plates in compression with post-buckling capacity. Category E3, where the element being considered is subject to gradual failure with warning of probable failure. This can include steel beams in bending or shear, under-reinforced concrete in bending, decks, and steel in tension at gross section Inspection level Evaluation shall not be undertaken without inspection. Inspection levels shall be classified as follows: (a) Inspection Level INSP1, where a component is not inspectable. This can include hidden members not accessible for inspection, e.g., interior webs of adjacent box beams. (b) Inspection Level INSP2, where inspection is to the satisfaction of the evaluator, with the results of each inspection recorded and available to the evaluator. (c) Inspection Level INSP3, where the evaluator has directed the inspection of all critical and substandard components and final evaluation calculations account for all information obtained during this inspection Important structures For structures that can affect the life or safety of people under or near a bridge, are essential to the local economy, or are designated as emergency route bridges (in accordance with Clause 4.4.2), a value of greater than that specified in Table 14.5 or 14.6 shall be used if directed by the Regulatory Authority. 660 (Replaces p. 660, November 2006)

74 14.14 Resistance General Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code General The factored resistances of concrete, structural steel, and wood components shall be determined in accordance with the applicable Sections of this Code. Components that do not meet the limitations on which the resistance calculations of this Code are based shall have their resistances calculated in accordance with alternative procedures based on established and generally recognized theories, analyses, and engineering judgment Prestressed concrete using stress-relieved strand or wire General The requirements of Section 8 for low-relaxation strand or wire shall be followed for the evaluation of prestressed concrete bridges using stress-relieved strand or wire, except as modified by Clauses to Prestressing steel stress limitations Stresses at jacking or transfer shall be based on data given on the Plans. In the absence of such data, the following stress limitations, for both pretensioning and post-tensioning, shall be used: (a) at jacking: 0.80f pu ; and (b) at transfer: 0.70f pu Loss of prestress At transfer In pretensioned components, the relaxation loss in prestressing steel, REL 1, initially stressed in excess of 0.5f pu shall be calculated as follows: REL 1 log( 24t ) f = 10 f sj py 055. f sj After transfer The loss of prestress due to relaxation after transfer, REL 2, shall be calculated as follows: f st CR + SH REL2 = f fpu 125 f. pu pu 001f. pu Prestressing steel stress at the ultimate limit state The steel stress, f ps, at the ultimate limit state in bonded prestressing steel shall be calculated using a method based on sectional strain compatibility and using stress-strain curves representative of the steel, except that if f se 0.5f pu, the value of f ps may be calculated as follows: f ps m f = fpu fc ppu (Replaces p. 665, November 2006) 665

75 S6S Concrete deck slabs General When the concrete deck slab is at least 175 mm thick and the requirements for the empirical design method in accordance with Clause are satisfied, the deck slab shall be deemed to have adequate resistance for the CL loadings specified with a value of W not greater than 625 kn in Clauses to When the concrete deck slab is less than 175 mm thick, W is greater than 625 kn, or the requirements of Clause are not satisfied, an evaluation of the deck slab shall be carried out in accordance with Clauses and Method of analysis If all of the conditions specified in Items (a) to (e) are satisfied, the factored resistance shall be determined in accordance with the simplified method specified in Clause ; otherwise, the resistance shall be determined in accordance with Section 8 and expressed as an equivalent wheel load: (a) the centre-to-centre spacing of the supporting beams for a slab panel does not exceed 4.5 m and the slab extends sufficiently beyond the external beams to provide full development length for the bottom transverse reinforcement; (b) the ratio of the spacing of the supporting beams to the thickness of the slab does not exceed 20; (c) the minimum slab thickness of sound concrete is at least 150 mm (with the minimum slab thickness used for slabs of variable thickness); (d) all cross-frames or diaphragms extend throughout the cross-section of the bridge between external girders and the maximum spacing of such cross-frames or diaphragms is in accordance with Clause ; and (e) edge stiffening is in accordance with Clause Simplified method If all of the conditions of Clause are satisfied, the value of the factored resistance, R r, shall be calculated as follows: R r = md R n where md = 0.5 The values of R n for both composite and non-composite concrete deck slabs shall be calculated as follows: R n = R d F q F c where R d is taken from Figure 14.4 or 14.5, as applicable, for the deck thickness, d, and the deck span being considered; F q is a correction factor based on q, where q = 50 (A s /bd + A st /bd t ); and F c is a correction factor based on f c. The values of F q and F c shall be taken from Figure 14.4 or 14.5, as applicable, or obtained from those figures by linear interpolation. For deck thicknesses other than those shown in Figures 14.4 and 14.5, the value of R n shall be obtained by linear interpolation. 666 (Replaces p. 666, November 2006)

76 0.9 Spacing as a fraction of d v s r2 s r Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code (V f V p )/(f c b v d v f c ) Figure 14.7 Spacing requirements for minimum reinforcement as a fraction of shear depth (See Clause ) Proportioning of transverse reinforcement General For the purpose of evaluation, Clause shall apply in lieu of Clause Amount of transverse reinforcement Provided that the cross-section does not change abruptly within a length equal to the member depth, h, and the load is applied through the top face of the beam, the amount of transverse reinforcement, A v h/s, may be taken as the total amount calculated within the length h. This length shall be measured from the section of interest toward the support Wood General The resistances for beam and stringer grade and post and timber grade wood members of Select Structural Grade and Grade 1 quality shall be determined in accordance with Clauses and All other wood resistances shall be determined in accordance with Section 9. (Replaces p. 671, November 2006) 671

77 S6S Shear The shear resistance in wood shall be taken from Clause 9.7, with f v u taken from Table and the size effect factor, k sv, taken as follows: ksv = 75 1 d 1+ 2 a/ d ( ) 2.5 where d = member depth For members older than five years, a shall be the distance measured from the centreline of the support to the tip of the end split. Where the split does not extend past the centreline of the support into the span, a shall be taken as zero. For members that are not older than five years, or where the end split length has not been measured, a shall be assumed to be 0.33d for Select Structural Grade and 0.75d for Grade Specified strengths and moduli of elasticity The specified strengths and moduli of elasticity shall be obtained from Table Table Specified strengths and moduli of elasticity for beam and stringer grades and post and timber grades, MPa (See Clauses and ) Species Combination Grade Bending at extreme fibre, ƒ bu Longitudinal shear, ƒ vu Compression parallel to grain, ƒ pu Compression perpendicular to grain, ƒ qu Tension parallel Modulus of elasticity to grain, ƒ tu E 50 E 05 Douglas fir Larch SS No Hem-Fir SS No Spruce- Pine-Fir SS No Northern species SS No Note: See Clause 9.3 for the symbols used in this Table Shear in steel plate girders with intermediate transverse stiffeners Clauses and shall be used to calculate the shear resistance of steel plate girders with intermediate transverse stiffener plates on one side of the web if the width-to-thickness ratio of the plate does not exceed 400/ F y Resistance adjustment factor For all components that have no visible sign of defect or deterioration, the factored resistance, as calculated in accordance with Clause , shall be multiplied by the appropriate resistance adjustment factor, U, specified in Table Where no value for U is specified in Table and in lieu of better information, a value of U = 1.0 may be used. 672 (Replaces p. 672, November 2006)

78 14.17 Bridge posting General Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The calculations for the live load capacity factors for establishing posting limits shall be carried out in accordance with Clause or In certain cases, a single posting load, based on engineering judgment and experience, may be used, subject to Approval. Posting methods other than those specified in Clause 14.17, may be used, subject to Approval. Subject to Approval, a concrete bridge with multiple load paths need not be posted if it has been carrying normal traffic without signs of excessive material cracking, deformation, or degradation. Such a bridge shall be inspected at intervals recommended by the evaluator Calculation of posting loads When Evaluation Levels 1, 2, and 3 are used as a basis for posting, the smallest value of F from Clause or shall be calculated and applied as follows: (a) when F 1.0 for Evaluation Level 1, posting shall not be required; (b) when 1.0 > F 0.3 for Evaluation Level 1, triple posting shall be required, with the posting loads for each evaluation level being obtained from Figure 14.8 for the appropriate value of F for each evaluation level; (c) (d) when F < 0.3 for Evaluation Level 1 and F 0.3 for Evaluation Level 3, single posting corresponding to Evaluation Level 3 shall be required, with the posting load being obtained from Figure 14.8 for Evaluation Level 3 only; and when F < 0.3 for Evaluation Level 3, consideration shall be given to closing the bridge. (Replaces p. 677, November 2006) 677

79 S6S1-10 Live load capacity factor, F Evaluation Level 3 Evaluation Level Evaluation Level Posting signs Posting factor, P Figure 14.8 Posting loads for gross vehicle weight (See Clauses and ) General The posted weight limit(s) in tonnes shall be PW, where P is the posting factor shown in Figure 14.8 and W is in kilonewtons and as specified in Clause For ONT loads specified for use in Ontario, W equals 625 kn Single posting signs for vehicles Posting signs shall be in accordance with the regulations set by the Regulatory Authority. Posting shall show the gross vehicle weight to the nearest tonne. 678 (Replaces p. 678, November 2006)

80 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Restricted highway live loads For bridges to be rehabilitated and posted for restricted highway live loads, the dynamic load allowance specified in Section 3 shall be multiplied by the dynamic load allowance modification factor specified in Clause Thermal, shrinkage, and creep effects Provision shall be made in the rehabilitation design for expansion and contraction due to temperature, shrinkage, and creep. Load effects induced by any restraints on these movements shall be included in the rehabilitation design Wind loads Wind loads shall be as specified in Section Collision loads Collision loads in accordance with Section 3 shall be considered unless effective measures are taken to protect the bridge and its components against these loads Settlement and permanent deformations Load effects resulting from settlement and permanent deformations in the bridge or its components shall be included in the rehabilitation design Seismic loads Seismic loads shall be considered in accordance with Section Stream flow and ice pressure loads Load effects resulting from stream flow and ice pressure shall be considered in accordance with Section Component deterioration Load effects resulting from redistribution of loads due to deterioration of components shall be included in the rehabilitation design Loads induced by the rehabilitation Loads induced in the bridge or its components during rehabilitation construction and any changes in the bridge or its components resulting from the rehabilitation shall be included in the rehabilitation design Load factors and load combinations General Unless otherwise specified by the Regulatory Authority, all load factors and load combinations shall be in accordance with Section Minimum rehabilitation load factors If the purpose of the rehabilitation is to allow passage of a permit vehicle (see Clause ), the load factors shall be in accordance with Section 14. The reliability index,, for all rehabilitated members shall be selected using Inspection Level INSP1. If specified by the Regulatory Authority, load factors from Section 14 may be used for a bridge rehabilitation intended to carry normal traffic, but shall be selected using Inspection Level INSP Total factored load effect For each load combination, every load that is to be included shall be multiplied by the specified load factor and then added to the other loads to obtain the total factored load effect. (Replaces p. 691, November 2006) 691

81 S6S Overall minimum load factor Except for PB or PC vehicles, the total factored load effect for ULS Combination 1 (see Table 3.1) shall not be less than 1.25 times the sum of the unfactored load effects. This requirement may be waived if the member provides a live load capacity factor, F, greater than or equal to 1.0 in accordance with the mean load method specified in Clause For PC vehicles, the total factored load effect for ULS Combination 1 shall not be less than 1.15 times the sum of the unfactored load effects Analysis Structural analysis shall be performed in accordance with this Section and the other applicable Sections of this Code. The effects of member connections, connection continuity, support restraints, the contribution of the secondary components, and the interaction between the new and existing components of the bridge shall be considered in the analysis. Structural analysis shall consider the extent of member deterioration and existing locked-in stresses due to system behaviour, their effect on the strength and stiffness characteristics of the member, and their effect on the strength of the structural system Resistance Existing members General The factored resistances of existing members, including existing members strengthened with new material, shall be determined in accordance with Clauses and The factored resistances of existing members shall be reduced to account for any member defects or deterioration in accordance with Clause In addition, the effects on member resistance and ductility of different stress levels in the new and existing portions of hybrid members shall be considered Strengthening using fibre-reinforced polymer In addition to satisfying the requirements of Clause , members strengthened using fibre-reinforced polymer shall satisfy the durability requirements of Clause The design of concrete or wood members strengthened with fibre-reinforced polymer shall also satisfy the requirements of Clause or 16.12, respectively New members The factored resistances of new members shall be determined in accordance with Sections 5 to 13 and (Replaces p. 692, November 2006)

82 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Open time the maximum time for joining together adherents after adhesive has been applied in order to avoid surface alteration of the adhesive. Plate an FRP component whose thickness is significantly less than its other dimensions. Pot life the time one can work with primer, putty, and/or adhesive after mixing resin and a hardener before the primer, putty, and/or adhesive starts to harden in the mixture vessel. Primary reinforcement reinforcement provided mainly for strength. Rope an assembly of bundled continuous fibres. Secondary reinforcement reinforcement provided mainly for control of cracking. Sheath a protective encasement for a tendon or rope. Sheet a flexible component comprising fibres. Shelf life the length of time a material can be stored under specified environmental conditions and still continue to meet all applicable specifications for use. Slab a concrete slab that transfers load directly to the substructure. Strand a linear component that constitutes all or part of a tendon. Strap a linear component of steel or FRP that provides transverse restraint externally in a deck slab. Stressed log bridge a bridge deck made with logs that are trimmed to obtain two parallel faces and that are post-tensioned transversely. Stressed wood deck a stress-laminated wood deck or stressed log bridge. Stress-laminated wood deck a laminated wood deck that is post-tensioned perpendicular to the deck laminates. Supporting beam a stringer, floor beam, or girder. Tendon an FRP or high-strength steel element that imparts prestress to a structural component. Thermoplastic matrix a polymer capable of being repeatedly softened by an increase in temperature and hardened by a decrease in temperature. Thermoset matrix a polymer that changes into a substantially infusible and insoluble material when cured by heat, chemicals, or both. Wet lay-up a method of making an FRP-laminated product that involves applying a resin system as a liquid when the fabric is put in place Abbreviations and symbols Abbreviations The following abbreviations apply in this Section: AFRP aramid-fibre-reinforced polymer CFRP carbon-fibre-reinforced polymer FLS fatigue limit state FRC fibre-reinforced concrete (Replaces p. 697, November 2006) 697

83 S6S1-10 FRP fibre-reinforced polymer GFRP glass-fibre-reinforced polymer NSMR near-surface-mounted reinforcement SLS serviceability limit state ULS ultimate limit state Symbols The following symbols apply in this Section: A = area of cross-section of a strap or bar, mm 2 A FRP = area of cross-section of an FRP bar, plate, sheet, or tendon, mm 2 A f = area of cross-section of deck slab formwork along a section parallel to the beams, per unit length of the formwork, mm 2 /mm A p = area of steel tendons in the tension zone, mm 2 A s = area of cross-section of steel or FRP reinforcing bars used in edge stiffening of deck slabs, as shown in Figures 16.2 and 16.5, mm 2 A v = area of transverse shear reinforcement perpendicular to the axis of a member, mm 2 A v,min = minimum required area of transverse shear reinforcement perpendicular to the axis of a member, mm 2 b = smallest log diameter, mm; height of the flat face of a trimmed log, as shown in Figure 16.10, mm; width of a rectangular section, mm b v = effective width of web within depth d long, mm (see Clause ) b w = width of web of a T-section, mm D g = diameter of a circular column or equivalent diameter of a rectangular column, mm (see Clause ) d = effective depth of a reinforced concrete component, being the distance from the compression face to the centroid of the tensile reinforcement, mm d FRP = effective shear depth for FRP, mm, calculated in the same manner as d long for longitudinal reinforcement d b = equivalent diameter of a bar, tendon, or strand in a multiple-strand tendon, mm d c = distance from the centroid of the tension reinforcement to the extreme tension surface of concrete, mm d cs = smaller of the distance from the closest concrete surface to the centre of the bar being developed, or two-thirds the centre-to-centre spacing of the bars being developed, mm d long = effective shear depth for longitudinal reinforcement, mm d s = diameter of an FRP stirrup in Clause (c), mm; distance from the top of the slab to the centroid of the bottom transverse FRP bars in Clause (b), mm E = modulus of elasticity, MPa E FRP = mean modulus of elasticity of FRP bars, plates, sheets, and tendons, MPa E p = modulus of elasticity of steel tendons, MPa E s = modulus of elasticity of steel, MPa E vfrp = modulus of elasticity of the FRP stirrups, MPa (see Clause ) EI = flexural rigidity, N mm 2 F = live load capacity factor (see Clause ) F SLS = dimensionless factor (see Clause ) F s = factor in Clauses (c) and (g), MPa F t = dimensionless factor (see Clause ) 698 (Replaces p. 698, November 2006)

84 f FRP = stress in the tension FRP reinforcement, MPa f FRPbend = specified tensile strength of the straight portion of an FRP bent stirrup, MPa Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code f FRPu = specified tensile strength of an FRP bar, grid, plate, sheet, tendon, or aramid rope, MPa f bu = specified bending strength of wood, MPa f c = specified compressive strength of concrete, MPa f cc = compressive strength of confined concrete, MPa f cr = cracking strength of concrete, MPa f FRP = confinement pressure due to FRP strengthening at the ULS, MPa f po = stress in tendons when the stress in the surrounding concrete is zero, MPa f ps = maximum permissible stress in a tendon at the ULS, MPa f vu = specified shear strength of timber (see Section 9) f y = specified yield strength of steel reinforcing bars, MPa h = depth of a timber beam, mm h 1 = distance from the centroid of tension reinforcement to the neutral axis, mm h 2 = distance from the extreme flexural tension surface to the neutral axis, mm J = overall performance factor for a concrete beam or slab with a rectangular section or a T-section K bfrp = non-dimensional factor (see Clauses and ) K tr = transverse reinforcement index, mm (see Clause ) K vfrp = non-dimensional factor (see Clauses and ) k b = coefficient depending on bond between FRP and concrete k 1 = bar location factor (see Clause ); concrete strength factor (see Clause ) k 2 = non-dimensional factor (see Clause ) k 4 = bar surface factor L e = effective anchorage length of an FRP sheet, mm (see Clause ) L u = unsupported length of a transverse edge beam, mm a = minimum required anchorage length for externally bonded FRP beyond the point where no strengthening is required, mm d = development length of FRP bars and tendons, mm M c = moment at a section corresponding to a maximum compressive concrete strain of 0.001, N mm M cr = cracking moment, N mm M f = factored moment at a section, N mm M r = factored flexural resistance of a section, N mm M ult = ultimate moment capacity of a section, N mm N f = factored axial load normal to the cross-section occurring simultaneously with V f, including the effects of tension due to creep and shrinkage, N n = number of test specimens P o = factored axial resistance of a section in pure compression, N P r = factored axial resistance of a section in compression with minimum eccentricity, N R i = post-cracking residual strength index r = radius of curvature of the bend of an FRP stirrup, mm; radius of curvature of the saddle for a deflected straight tendon, mm S = centre-to-centre spacing of beams supporting a deck slab, mm S = spacing of straps, mm (Replaces p. 699, November 2006) 699

85 S6S1-10 s = spacing of shear or tensile reinforcement, mm s FRP = spacing of externally bonded FRP bands on concrete for shear strengthening, measured along the axis of the member, mm T gw = wet glass transition temperature, i.e., the glass transition temperature after moisture uptake by the polymer, C t = thickness of an externally restrained deck slab, including that of the stay-in-place formwork, if present, mm t FRP = total thickness of externally bonded FRP plates or sheets, mm t c = thickness of cast-in-place concrete in a deck slab cast on a stay-in-place formwork, if present, mm t s = projection of a shear connector or other shear-connecting device into a deck slab, as shown in Figure 16.1 for shear connectors, mm V = coefficient of variation of the strength of FRP components, being the ratio of the standard deviation to the mean V FRP = factored shear resistance provided by the FRP shear reinforcement, N V c = factored shear resistance provided by tensile forces in concrete, N V f = factored shear force at a section, N V p = component in the direction of the applied shear of all of the effective prestressing forces crossing the critical section, factored by p (see Clause 8.4.6), to be taken as positive if resisting the applied shear, N V r = factored shear resistance, N V s = factored shear resistance provided by the steel shear reinforcement, N V st = factored shear resistance provided by the shear reinforcement, N w FRP = width of an FRP sheet measured perpendicular to the direction of the main fibres, mm w cr = crack width at the tensile face of the flexural component, mm = angle of inclination of internal or external transverse reinforcement to the longitudinal axis of the member, degrees = factor used to account for shear resistance of cracked concrete FRPe = effective strain in FRP (see Clause ) FRPu = ultimate strain in FRP v = strain in an FRP stirrup x = longitudinal strain calculated in accordance with Clause = angle of inclination of the principal diagonal compressive stress to the longitudinal axis of the member, degrees V = bond reduction factor (see Clause ) s = ratio of the cross-sectional area of the longitudinal FRP reinforcement to the effective cross-sectional area of the beam vfrp = ratio of the total cross-sectional area of the legs of an FRP stirrup to the product of the width of the beam and the spacing of the stirrups N = stress in concrete due to axial loads, MPa v = stress calculated in accordance with Clause FRP = resistance factor for FRP components (see Clause ) c = resistance factor for concrete (see Clause 8.4.6) c = curvature at a section when the moment is M c, mm 1 ult = curvature at a section when the moment is M ult, mm (Replaces p. 700, November 2006)

86 Resistance factor Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The resistance factor, FRP, for pultruded FRP and aramid fibre rope shall be as specified in Table For non-pultruded FRP made by wet lay-up, FRP shall be 0.75 times the corresponding value in Table For non-pultruded FRP made in accordance with other factory-based controlled processes, FRP shall be 0.85 times the corresponding value in Table Table 16.2 FRP for pultruded FRP and aramid fibre rope (See Clause ) Application FRP AFRP reinforcement in concrete and NSMR 0.65 AFRP in externally bonded applications 0.55 AFRP and aramid fibre rope tendons for concrete and timber components 0.60 CFRP reinforcement in concrete 0.80 CFRP in externally bonded applications and NSMR 0.80 CFRP tendons 0.80 GFRP reinforcement in concrete 0.55 GFRP in externally bonded applications and NSMR 0.70 GFRP tendons for concrete components 0.55 GFRP tendons for timber decks Fibre-reinforced concrete General Randomly distributed fibre reinforcement shall be permitted in deck slabs, barrier walls, and surfacing of stressed log bridges for the control of cracks that develop in concrete during its early life. Its use in other applications shall require Approval Fibre volume fraction The fibre volume fraction shall be such that the residual strength index, R i, is at least that specified by Table 16.3 for the particular application, where R i is calculated as R i = ARS/R where ARS = mean value of the average residual strength determined using the ASTM C 1399 test on at least five fibre-reinforced concrete beam specimens R = mean value of the modulus of rupture determined by performing the ASTM C 78 test on at least five fibre reinforced concrete specimens (Replaces p. 703, November 2006) 703

87 S6S1-10 Table 16.3 Minimum values of R i for various applications (See Clause ) Application Barrier wall with one mesh of bars 0.25 Barrier wall with two meshes of bars 0.0 * Deck slab with one crack-control mesh 0.25 Deck slab with two crack-control meshes 0.0 * Surfacing of stressed log bridges 0.30 *Fibres not needed. Minimum value of R i Fibre dispersion in concrete Fibres shall be mixed uniformly in concrete. The Plans shall specify that before a given mix of FRC is used in the structure, the uniformity of dispersion of the fibres shall be confirmed visually. As an additional measure, the possibility of non-uniform fibre dispersion shall be estimated by comparing the compressive strength of FRC with that of the corresponding plain concrete using 7-day compressive strength tests in accordance with CAN/CSA-A23.1. If the FRC mix has a mean compressive strength less than 90% of that of the corresponding plain concrete, engineering judgment shall be exercised to determine corrective measures Externally restrained deck slabs General An externally restrained deck slab supported on parallel longitudinal beams that complies with Clause , , or and satisfies the following conditions need not be analyzed except for negative transverse moments due to loads on the overhangs and barrier walls, and for negative longitudinal moments in continuous span bridges: (a) The deck slab is composite, with parallel supporting beams in the positive moment regions of the beams. (b) The spacing of the supporting beams, S, does not exceed 3000 mm. (c) The total thickness of the deck slab, including that of the stay-in-place formwork, if present, t, is at least 175 mm and at least S/15. (d) The supporting beams are connected with transverse diaphragms or cross-frames at a spacing of not more than 8000 mm. (e) The deck slab is confined transversely by straps or a stay-in-place formwork in accordance with the (f) applicable provisions of Clause , , or When the deck slab is confined by straps, the distance between the top of the straps and the bottom of the slab is between 25 and 125 mm, as shown in Figure (g) The projection of the shear connectors in the deck slab, t s, is at least 75 mm, as shown in Figure 16.1, or additional reinforcement with at least the same shear capacity as that of the shear connectors is provided and the projection of the additional reinforcement into the slab is at least 75 mm. (h) The cover distance between the tops of the shear-connecting devices and the top surface of the deck slab is at least 75 mm when the slab is not exposed to moisture containing de-icing chemicals; otherwise, this cover distance is at least 100 mm or the shear-connecting devices have an Approved coating. 704 (Replaces p. 704, November 2006)

88 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code (i) The fibre volume fraction in the cast-in-place concrete is in accordance with Clause (j) The deck slab contains appropriate tensile reinforcement for transverse negative moments resulting from loads on deck slab overhangs and loads on railings or barrier walls. (k) The transverse edges of the deck slab are stiffened by composite edge beams with a minimum 4 flexural rigidity, EI, in the plane of the deck slab of 3.5L u N mm 2, where L u is the unsupported length of the edge beam, or, for an unsupported length of edge beam less than 4250 mm, the details of the transverse edge beams are as shown in Figure 16.2, 16.3, 16.4, or (l) For continuous span bridges, the deck slab contains longitudinal negative moment reinforcement in at least those segments where the flexural tensile stresses in concrete for the SLS cases are larger than 0.6f cr, where f cr is calculated as follows: f cr = 04. f c (m) The spacing of the reinforcement bars shall not exceed 300 mm. The diameter of reinforcement bars shall not be less than 15 mm. When the conditions specified in this Clause and the requirements specified in Clause , , or , as applicable, are not satisfied, the design of the externally restrained deck slab shall require Approval Full-depth cast-in-place deck slabs The design of an externally restrained deck slab with full-depth cast-in-place construction shall meet the requirements of Clause and the following requirements: (a) The top flanges of all adjacent supporting beams shall be connected by straps that are perpendicular to the supporting beams and either connected directly to the tops of the flanges, as in the case of the welded steel straps shown in Figure 16.6, or connected indirectly, as in the case of the partially studded straps shown in Figure 16.7; alternatively, the transverse confining system shall comprise devices that have been proved through Approved full-scale laboratory testing. (b) The spacing of straps, S, shall be not more than 1250 mm. (c) Each strap shall have a minimum cross-sectional area, A, in mm 2, as follows: where F s = 6.0 MPa for outer panels and 5.0 MPa for inner panels E = modulus of elasticity of the strap material In the case of FRP straps, the main fibres shall be in the direction perpendicular to the supporting beams. (d) The direct or indirect connection of a strap to the supporting beams shall be designed to have a minimum shear strength in newtons of 200A. (e) In a negative moment region of a supporting beam, where the beam is not made composite, shear-connecting devices shall be provided on the beam in the vicinity of the straps, and have a minimum total shear strength in newtons of 200A (as shown, e.g., in Figure 16.8). As shown in Figure 16.7, such shear-connecting devices shall be within 200 mm of the nearest strap. (f) The deck slab shall have a crack-control orthogonal assembly of GFRP bars placed near the bottom of the slab, with the area of the cross-section of the GFRP bars in each direction being at least t mm 2 /mm. When steel straps are welded to steel girders in negative moment regions, the fatigue of the girder shall be considered. When the conditions specified in Clause and the requirements specified in this Clause are not satisfied, the design of the slab shall require Approval. (Replaces p. 705, November 2006) 705

89 S6S Cast-in-place deck slabs on stay-in-place formwork The design of an externally restrained deck slab with cast-in-place construction on stay-in-place formwork shall meet the requirements of Clause and the following requirements: (a) The design of the formwork shall take into account its anticipated handling and anticipated conditions during construction. (b) The effective span of the formwork shall be taken as the distance between the edges of the supporting beams plus 150 mm. (c) The deflection of the formwork during construction shall not exceed 1/240 of the effective span of the formwork. (d) The ends of the formwork shall be supported on beams in such a manner that after placement of concrete topping a support length of at least 75 mm shall be provided under the lower portions of the formwork. Such support shall be within 25 mm of the closer edges of the supporting beams. (e) The top flanges of all adjacent supporting beams shall be connected by external straps or the formwork itself. (f) When the deck slab is confined by straps, the straps and their connections shall be designed to satisfy the requirements specified in Items (a) to (e) of Clause (g) When the deck slab is restrained by a formwork, the concept shall have been verified by tests on full-scale models. In addition, the minimum area of cross-section of the formwork, in mm 2 /mm, across a section parallel to the beams, A f, shall be calculated as follows: A f 2 FS s = Et where F s = 6.0 MPa for outer panels and 5.0 MPa for inner panels E = modulus of elasticity of the material of the formwork in the direction perpendicular to the supporting beams (h) When the deck slab is restrained by a formwork, the direct or indirect connection of the formwork to the supporting beams shall have been proved by full-scale tests to have a shear strength in N/mm of at least 200A f. (i) When the formwork is of precast concrete construction, it shall contain a crack-control orthogonal assembly of GFRP bars placed at its mid-depth, with an area of cross-section of GFRP bars in each direction equal to t mm 2 /mm. (j) When it is of precast construction, the formwork panel shall have a maximum thickness of 0.5t. (k) When it is of precast construction, the upper surface of the formwork panel shall be clean, free of laitance, and roughened to an amplitude of 2 mm at a spacing of nearly 15 mm. (l) The cast-in-place concrete shall have a crack-control orthogonal assembly of GFRP bars placed in the middle of the cast-in-place slab, with the area of the cross-section of the GFRP bars in each direction being at least t c mm 2 /mm. When the conditions specified in Clause and the requirements specified in this Clause are not satisfied, the design of the slab shall require Approval Full-depth precast concrete deck slabs The design of an externally restrained deck slab with full-depth precast concrete construction shall require Approval. 706 (Replaces p. 706, November 2006)

90 16.8 Concrete beams and slabs Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code General Except as specified in this Section, the resistance and deformations of concrete beams, slabs, and deck slabs reinforced with FRP tendons, bars, or grids, corresponding to the various limit states, shall be calculated in accordance with Section 8. The resistance at ULS for beams and slabs with FRP bars or grids in multiple layers shall be calculated by taking account of the linear variation of strain through the depth of the member, ensuring that the stresses in the reinforcement are consistent with Clause The maximum compressive concrete strains in beams and slabs due to factored loads shall not exceed the limiting strain specified in Section 8. Internally restrained deck slabs shall be designed in accordance with Clause Deformability and minimum reinforcement Design for deformability For concrete components reinforced with FRP bars or grids, the overall performance factor, J, shall be at least 4.0 for rectangular sections and 6.0 for T-sections, with J calculated as follows: Multy J = M y c ult c where M ult = ultimate moment capacity of the section ult = curvature at M ult M c = moment corresponding to a maximum compressive concrete strain in the section of c = curvature at M c Minimum flexural resistance The factored resistance, M r, shall be at least 50% greater than the cracking moment, M cr, as specified in Clause This requirement may be waived if the factored resistance, M r, is at least 50% greater than the factored moment, M f. If the ULS design of the section is governed by FRP rupture, M r shall be greater than 1.5M f. The principles for calculating M cr and M r shall be consistent with those specified in Clause 8.8, except that stresses in FRP bars at different levels, if present, shall be calculated by assuming a linear distribution Crack-control reinforcement When the maximum tensile strain in FRP reinforcement under full service loads exceeds , cross-sections of the component in maximum positive and negative moment regions shall be proportioned in such a way that the crack width does not exceed 0.5 mm for members subject to aggressive environments and 0.7 mm for other members, with the crack width calculated as follows: w cr ffrp h2 2 E h k b d c s / 2 = +( ) FRP The value of k b shall be determined experimentally, but in the absence of test data may be taken as 0.8 for sand-coated and 1.0 for deformed FRP bars. In calculating d c, the clear cover shall not be taken greater than 50 mm. (Replaces p. 711, November 2006) 711

91 S6S Non-prestressed reinforcement The maximum stress in FRP bars or grids under loads at SLS shall not be more than F SLS f FRPu, where F SLS is as follows: (a) for AFRP: 0.35; (b) for CFRP: 0.65; and (c) for GFRP: Development length for FRP bars and tendons General The development length, d, for FRP bars in tension shall be calculated as follows: where f FRP = stress in the tension reinforcement at ULS In addition, d shall not be taken as less than 250 mm. All of the variables in this equation shall be in accordance with Clause , except as follows: (a) The variable k 4 is the bar surface factor, being the ratio of the bond strength of the FRP bar to that of a steel deformed bar with the same cross-sectional area as the FRP bar, but not greater than 1.0. In the absence of experimental data, k 4 shall be taken as 0.8. (b) The variable E FRP is the modulus of elasticity of the FRP bar. (c) The term (d cs + K tr E FRP /E s ) shall not be taken greater than 2.5d b. (d) The bond strength of the FRP bar shall be determined by testing or taken to be the bond strength specified by the manufacturer of the bar Splice length for FRP bars The splice length for FRP bars in tension shall be 1.3 d, where d is calculated in accordance with Clause Spliced FRP bars shall not be separated by more than 150 mm Development length for FRP grids For FRP grids in which the intersecting orthogonal bars have been demonstrated to be fully anchored, the development length shall include at least two transverse bars of the grid lying perpendicular to the direction of the force under consideration Tendons Supplementary reinforcement A structure incorporating concrete beams or slabs with FRP tendons shall contain supplementary reinforcement capable of sustaining the unfactored dead loads or have alternative load paths such that the failure of one beam or a portion of a slab will not lead to progressive collapse of the structure Stress limitations for tendons For straight tendons, the maximum stress at jacking and transfer shall not exceed the values specified in Table For curved tendons, the maximum stresses at jacking and transfer shall be those specified in Table 16.4, reduced by an amount determined from tests. FRP tendons shall be stressed to provide a minimum effective prestress of 75% of the stresses at transfer. The maximum SLS stresses after all prestress losses shall not exceed the F SLS values specified in Clause (Replaces p. 712, November 2006)

92 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code The maximum stress in the tendons under factored loads at ULS, f ps, computed using a method based on strain compatibility, shall not exceed FRP f FRPu, where the resistance factor FRP is as specified in Clause Table 16.4 Maximum permissible stresses in FRP tendons at jacking and transfer for concrete beams and slabs for pretensioning and post-tensioning systems (See Clauses and ) Capacity of anchors When tested in an unbonded condition, anchors for post-tensioning tendons shall be capable of developing a tendon force at least 50% higher than the jacking force, but not more than 90% of the specified tensile strength of the tendons, without exceeding the anticipated set. After tensioning and seating, anchors shall sustain applied loads without slippage, distortion, or other changes that result in loss of prestress. The Plans shall specify that at least two anchors are to be tested to confirm this requirement End zones in pretensioned components The end zones of pretensioned concrete components shall be reinforced against splitting unless it can be demonstrated that such reinforcement is unnecessary Protection of external tendons External tendons comprising glass or aramid fibres shall be protected against ultraviolet rays by encasing them in protective sheaths; carbon fibre external tendons with ultraviolet-susceptible matrices shall also be similarly protected. Aramid fibre ropes shall be protected by sheaths and watertight anchors against the ingress of moisture Design for shear Tendon At jacking At transfer AFRP 0.40f FRPu 0.35f FRPu CFRP 0.70f FRPu 0.65f FRPu GFRP 0.30f FRPu 0.25f FRPu For concrete beams reinforced with steel or FRP longitudinal reinforcement, and with steel or FRP stirrups, the factored shear resistance, V r, shall be calculated as follows: V r = V c + V st + V p where V st = V s or V FRP (in accordance with the type of stirrups used in the beam) Clause shall be used to calculate V c, V s, and V p, except as follows: (a) Instead of calculating V c in accordance with Clause , the following equation shall be used: V = 25. bf f b d c c cr v long The effective shear depth, d long, shall be calculated in accordance with Clause , and shall be calculated in accordance with Clause , after using the value of x in Clause (b). (Replaces p. 713, November 2006) 713

93 S6S1-10 (b) (c) Instead of calculating x in accordance with Clause , one of the following equations shall be used: Mf + Vf Vp Nf ( Apfpo) d (i) long e x = EA + E A (ii) For the factored shear resistance carried by FRP shear reinforcement, V FRP, the following equations shall be used: (i) for components with transverse reinforcement perpendicular to the longitudinal axis: (ii) e x V FRP M d = ( s s p p) f + Vf Vp Nf ( AFRPfpo ) long 2( EA + E A ) s s FRP FRP FRPAv vdlong = f s cotq s for components with transverse reinforcement inclined at an angle to the longitudinal axis: ffrpavsvdlong(cotq + cot a) sina VFRP = s For the equations in Items (i) and (ii), shall be obtained from Clause for the general method; the coefficient FRP shall be as specified in Clause ; and v shall be the smaller of the values obtained from the following two equations: ( ) 005. r / d f s FRPbend s v = = E vfrp v 15. (d) where v = The minimum amount of shear reinforcement, A v,min, shall be calculated as follows: b s A v,min = 006. f w c s v where v is as specified in Item (c) Internally restrained cast-in-place deck slabs Design by empirical method The requirements of Clause 8.18 pertaining to cast-in-place deck slabs shall apply to cast-in-place deck slabs with FRP bars or grids, except that when the deck slab is designed using the empirical method of Clause , the following requirements shall be met in lieu of those specified in Items (a) and (c) of Clause : (a) the deck slab shall contain two orthogonal assemblies of FRP bars, with the clear distance between the top and bottom transverse bars being at least 55 mm. The diameter of reinforcement bars shall not be less than 15 mm; (b) for the transverse FRP bars in the bottom assembly, the minimum area of cross-section in mm 2 /mm shall be 500d s /E FRP ; and (c) the longitudinal bars in the bottom assembly and the transverse and longitudinal bars in the top assembly shall be of GFRP with a minimum s of (Replaces p. 714, November 2006)

94 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Consistent with the requirements of Clause , the requirements of Clause shall be waived for decks designed using the empirical method. The edge-stiffening details shall be as shown in Figures 16.2 to Design for flexure For cast-in-place deck slabs with FRP bars or tendons designed for flexure, the requirements of Clauses to shall apply. In addition, the requirements of Clause shall be satisfied for diaphragms. The distribution reinforcement shall be designed in accordance with Clause In addition, the spacing of the reinforcement in each direction shall not exceed 300 mm. The diameter of reinforcement bars shall not be less than 15 mm Stressed wood decks General Clauses to shall apply to stress-laminated wood decks and stressed log bridges that are post-tensioned with FRP or fibre rope tendons Post-tensioning materials Tendons GFRP, AFRP, and aramid ropes shall be permitted as tendons in stressed wood decks. The design of stressed laminated wood decks shall comply with Section 9 (with the exception of Clause ) and Clauses to Anchors Anchors shall be capable of developing a tendon force at least 50% higher than the jacking force. The Plans shall specify that at least two anchors are to be tested to confirm this requirement Stress limitations At initial stressing, the stresses shall not exceed 0.35f FRPu for GFRP tendons or 0.40f FRPu for AFRP and aramid rope tendons Post-tensioning system For stressed log bridges, the post-tensioning system shall be external or internal (the external system is shown in Figure 16.9). For stress-laminated wood decks, the post-tensioning system shall be as shown in Figure 9.5 or 9.6, except that the tendons shall comprise GFRP, AFRP, or aramid ropes. When lower tendons in decks with external post-tensioning are exposed to damage from flowing debris, they shall be suitably protected. (Replaces p. 715, November 2006) 715

95 S6S1-10 Steel channel bulkhead Anchor Anchorage plate Wood bearing block Anchorage nut Safety nut 5 mm (minimum) Fibre tendon with protective tubing Figure 16.9 Post-tensioning system for stressed log bridges (See Clause ) Stressing procedure The initial post-tensioning forces in the tendons shall be such as to bring the average interface pressure between wood laminates or logs to approximately 0.8 MPa, regardless of the species concerned. These forces shall be reduced 12 to 24 h after initial post-tensioning to establish an average interface pressure of 0.35 to 0.44 MPa, at which level the stresses in the tendons shall not exceed the relevant values specified in Table 16.4 for post-tensioning at transfer Design of bulkheads Stressed wood decks shall incorporate steel distribution bulkheads, as specified in Clause , except that the factored bearing resistance, calculated in accordance with Clause , shall be for the reduced post-tensioning forces specified in Clause Stressed log bridges General A stressed log bridge shall be constructed of logs (a) that are (i) new; or (ii) used but structurally sound; and (b) whose exposed surfaces have been suitably treated in accordance with Section Log dimensions The logs in a stressed log bridge shall meet the following requirements: (a) the ratio of the largest to the smallest diameter of a log shall be not more than 1.10; (b) the out-of-straightness of a log shall be not more than times its length; (c) the end faces of a log shall be perpendicular to its axis to within an angular tolerance of 5 ; and (d) the logs shall be trimmed longitudinally so as to provide, at any transverse cross-section, two opposed faces that are parallel within an accuracy of (Replaces p. 716, November 2006)

96 Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Splicing at butt joints As shown in Figure 16.10, all butt joints shall be spliced by hot-dipped galvanized steel nail-plates with a minimum thickness of 1.5 mm. The nail-plates shall be installed by using a hydraulic jack or other Approved means to apply uniform pressure. 0.7b (min.) 2b (minimum) Height b Galvanized nail-plate 1.5 mm (minimum) thick Figure Spliced butt joint for logs (See Clause ) Frequency of butt joints The butt joints shall be staggered in such a way that within any band with a width of 1 m measured along the logs, a butt joint shall not occur in more than one out of four adjacent logs on each side of the log with a butt joint Holes in logs for an internal system The diameter of the holes drilled in the logs for an internal post-tensioning system shall be less than or equal to 20% of the minimum diameter of the logs Support anchorage A stressed log bridge shall be secured to the substructure by steel bars in accordance with the requirements of Clause for stress-laminated wood decks Surfacing The top of a stressed log bridge shall be surfaced by hot-mix asphalt or FRC incorporating low modulus polymer fibres. A fibre-reinforced concrete surfacing may be assumed to be acting compositely with the logs if the smallest thickness of concrete is not more than 50 mm Flexural resistance and stiffness The factored flexural resistance, M r, of a stressed log bridge shall be calculated in accordance with Clause 9.6.1, except that the value of f bu shall be obtained from Table 9.17, which shall also be used for obtaining the modulus of elasticity of the logs. (Replaces p. 717, November 2006) 717

97 S6S Barrier walls A barrier wall that has the details shown in Figure and satisfies the following conditions shall be deemed to have met the Performance Level 3 requirements of Section 12: (a) on the traffic side, the wall has a GFRP grid or an orthogonal assembly of GFRP bars providing a factored strength of 330 N per millimetre length of the wall in the vertical direction and 240 N per millimetre length of the wall in the horizontal direction; (b) the spacing of the bars in the GFRP grid or orthogonal assembly on the traffic side is not more than 300 mm; (c) the wall is reinforced with (i) one planar GFRP grid or an orthogonal assembly of GFRP bars near the surface, as shown in Figure 16.11, and FRC is used in accordance with Clause 16.6; or (ii) two layers of planar GFRP grid or two orthogonal assemblies of GFRP bars (in which case FRC is not needed); (d) if a planar GFRP grid or an orthogonal assembly of GFRP bars is provided away from the traffic side, it comprises bars of a diameter of at least 15 mm, at a spacing of 300 mm in the horizontal and vertical directions; (e) if only one planar GFRP grid or orthogonal assembly of GFRP bars is used, the wall is provided at mid-thickness near its top with two 19 mm diameter steel bars or two 15 mm diameter GFRP bars, as shown in Figure 16.11; (f) the wall is anchored to the slab by double-headed steel bars 19 mm in diameter and 500 mm long, or by bent GFRP bars whose performance has been established by Approved full-scale tests, at a spacing of 300 mm; (g) the spacing of the bars and anchors is reduced by half for the following lengths of the wall: (i) 1.2 m on each side of a joint in the wall; (ii) 1.2 m on each side of a luminaire embedded in the wall; and (iii) 1.2 m from the free vertical edges of the wall; and (h) the cover to GFRP bars (if any) meets the requirements of Clause and the cover to double-headed bars (if any) meets the requirements of Clause Barrier walls for Performance Levels 1, 2, and 3 with details other than those shown in Figure may be used if their performance has been established by Approved full-scale tests. 718 (Replaces p. 718, November 2006)

98 Flexural components Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Failure modes For a section strengthened with FRP systems, the following flexural failure modes shall be investigated at ULS: (a) crushing of the concrete in compression before rupture of the FRP or yielding of the reinforcing steel; (b) yielding of the steel followed by concrete crushing before rupture of the FRP in tension; (c) yielding of the steel followed by rupture of the FRP in tension; (d) in the case of members with internal prestressing, additional failure modes controlled by the rupture of the prestressing tendons; and (e) peeling failure or anchorage failure of the FRP system at the cut-off point Flexural resistance to sustained and fatigue loads At SLS and/or FLS, stresses shall be calculated based on elastic analysis. The effect of the FRP system on the serviceability may be assessed using transformed section analysis. The initial stresses and strains related to unfactored dead loads in a beam before strengthening shall be considered. In addition to satisfying the requirements of Clause for SLS and Clause for FLS, the stress level in the FRP system due to all dead loads after strengthening and SLS live loads shall not exceed F SLS f FRPu, where the value of F SLS is obtained from Clause Factored flexural resistance The factored flexural resistance shall be calculated in accordance with Clause Anchorage lengths for flexure For externally-bonded FRP strengthening systems, the anchorage length beyond the point where no strengthening is required shall not be less than a, calculated as follows: l a = 05. E FRP t FRP In addition, the anchorage length shall be at least 300 mm or the FRP shall be suitably anchored. For NSMR, the anchorage length, d, beyond the point where no strengthening is required shall be calculated in accordance with Clause Compression components General For FRP-strengthened columns subjected to combined flexure and axial compression, the factored resistance shall be calculated in accordance with Clause Slenderness effects The slenderness effects shall be accounted for in accordance with Clauses and Maximum factored axial resistance For columns with FRP systems bonded to the external perimeter that meet the requirements of Clause , the factored axial resistance, P r, shall be less than or equal to 0.80P o. The confined concrete compressive strength determined in accordance with Clause may be used to evaluate P o Biaxial loading An analysis based on stress and strain compatibility for a loading condition of compression and biaxial bending shall be used to design the FRP strengthening system. (Replaces p. 721, November 2006) 721

99 S6S Transverse reinforcement If the existing steel transverse reinforcement does not meet the requirements of Clause , FRP transverse reinforcement shall be provided in accordance with Clause Axial load capacity enhancement The compressive strength of the confined concrete, f c c, shall be calculated as follows: f c c = f c + 2f FRP The confinement pressure due to FRP strengthening at the ULS, f FRP, shall be calculated as follows: f l FRP = 2f f D t FRP FRPu FRP g For columns with circular cross-sections, D g is the diameter of the column; for columns with rectangular cross-sections with aspect ratios less than or equal to 1.5 and a smaller cross-sectional dimension not greater than 800 mm, D g is equal to the diagonal of the cross-section. For columns with other polygonal cross-sections, D g is equal to the diameter of the circumscribed circle. The confinement pressure at the ULS shall be designed to be between 0.1f c and 0.33f c Shear rehabilitation with externally bonded FRP systems General Clause covers the proportioning of externally bonded FRP systems to increase the shear capacity of reinforced concrete beams and columns. The shear-strengthening scheme shall be of the type in which the fibres are oriented perpendicularly or at an angle to the member axis. The shear reinforcement shall be anchored by suitable means in the compression zone in accordance with one of the following schemes: (a) the shear reinforcement shall be fully wrapped around the section, as shown in Figure 16.12; (b) the anchorage to the shear reinforcement near the compression flange shall be provided by additional horizontal strips, as shown in Figure 16.12; and (c) the anchorage shall be provided in the compression zone, as shown in Figure However, an alternative anchorage scheme may be used if Approved. 722 (Replaces p. 722, November 2006)

100 Fully wrapped section Anchorage with horizontal strips Supplement No. 1 to CAN/CSA-S6-06, Canadian Highway Bridge Design Code Anchorage inside the slab Figure Anchorage methods in the compression zone of externally bonded FRP shear reinforcement (See Clause ) Factored shear resistance For reinforced concrete members with rectangular sections or T-sections and FRP reinforcement anchored in the compression zone of the member, the factored shear resistance, V r, shall be calculated as follows: V r = V c + V s + V FRP V c and V s shall be calculated in accordance with Clause and V FRP shall be calculated as follows: V FRP ffrpefrpefrpeafrpdfrp (cotq + cot a) sina = s FRP where FRPe = FRPu (for completely wrapped sections) = V FRPu (for other configurations) For continuous U-shaped configurations of the FRP reinforcement, the bond-reduction coefficient, V, shall be calculated as follows: k V kk 12Le = 11900e FRPu 075. where k k 1 2 ( ) = f / 27 c dfrp L = d FRP 2/ 3 e (Replaces p. 723, November 2006) 723

101 S6S1-10 L e = ( t E ) FRP FRP For prestressed concrete components, V r shall be the sum of V c, V s, V p, and V FRP. The equations in this Clause shall be used to calculate V FRP. The general method of Clause shall be used to calculate V c, V s, and V p. For components with non-rectangular or non-t cross-sections, a rigorous analysis or test shall guide the design Spacing and strengthening limits The spacing of FRP bands shall be not more than s FRP, calculated as follows: sfrp = wfrp +( dfrp /4) The total factored shear resistance subsequent to FRP strengthening, V r, shall not exceed the value given in Clause Rehabilitation of timber bridges General Clause applies to beams of timber and stringer grades strengthened with GFRP sheets or bars. The bars, if present, shall be near-surface mounted or embedded in holes in timber. The empirical methods specified in Clause may be used to determine the strength of timber beams strengthened with GFRP sheets or bars for flexure, shear, or both. Although the requirements of Clause are intended for GFRP bars and sheets, AFRP and CFRP bars and sheets may be used in place of GFRP bars and sheets. If the strength for either flexure or shear needs to be more than is provided by the empirical methods of Clause 16.12, experimental evidence shall be used to determine the amount of FRP reinforcement. The procedures for handling, storage, and protection of FRP sheets and bars shall be the same as those specified in Clause The Plans shall provide details and specifications relevant to the following and as specified in Annexes A16.1 and A16.2: (a) identification of the FRP strengthening systems and protective coatings; (b) surface preparation; (c) shipping, storage, and handling of the FRP strengthening systems; (d) installation of the FRP strengthening systems, including (i) spacing and positioning of the components; (ii) locations of overlaps and multiple plies; (iii) installation procedures; and (iv) constraints for climatic conditions; (e) the curing conditions of the strengthening systems; (f) the quality control of the strengthening systems, as specified in Annex A16.2; (g) staff qualifications; (h) material inspection before, during, and after completion of the installation; and (i) system maintenance requirements. Before a rehabilitation strategy is developed, an assessment of the existing structure or elements shall be conducted in accordance with Section (Replaces p. 724, November 2006)

102 CSA Standards Update Service CAN/CSA-S6-06 November 2006 Title: Canadian Highway Bridge Design Code Pagination: 788 pages (lv preliminary and 733 text), each dated November 2006 Automatic notifications about any updates to this publication are available.. To register for notifications, and/or to download any existing updates in PDF, enter the Online Store at and click on My Account on the navigation bar. The List ID for this document is To receive printed updates, please complete and return the attached card. Name Organization Address City Province/State Country Postal/Zip Code I consent to CSA collecting and using the above information to send me updates relating to this publication. Visit CSA s policy on privacy at to find out how we protect your personal information. CAN/CSA-S6-06

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108 Canadian Highway Bridge Design Code Contents Technical Committee on the Canadian Highway Bridge Design Code xxx Subcommittee on Section 1 General xxxii Subcommittee on Section 2 Durability xxxiii Subcommittee on Section 3 Loads xxxiv Subcommittee on Section 4 Seismic design xxxv Subcommittee on Section 5 Methods of analysis xxxvi Subcommittee on Section 6 Foundations xxxvii Subcommittee on Section 7 Buried structures xxxviii. Subcommittee on Section 8 Concrete structures xxxix Subcommittee on Section 9 Wood structures Subcommittee on Section 10 Steel structures xl xli Subcommittee on Section 11 Joints and bearings xlii Subcommittee on Section 12 Barriers and highway accessory supports xliii Subcommittee on Section 13 Movable bridges xliv Subcommittee on Section 14 Evaluation xlv Subcommittee on Section 15 Rehabilitation and repair Subcommittee on Section 16 Fibre-reinforced structures xlvi xlvii Code Calibration Task Force xlviii Editorial Task Force xlix French Translation Task Force l Regulatory Authority Committee li Preface lii Foreword lv Section 1 General Scope Scope of Code Scope of this Section Terminology Reference publications 2 November 2006 iii

109 CAN/CSA-S Definitions General General administrative definitions General technical definitions Hydraulic definitions General requirements Approval Design Evaluation and rehabilitation of existing bridges Construction Geometry Planning Structure geometry Barriers Superstructure barriers Roadside substructure barriers Structure protection in waterways Structure protection at railways Auxiliary components Expansion joints and bearings Approach slabs Utilities on bridges Durability and maintenance Durability and protection Bridge deck drainage Maintenance Hydraulic design Design criteria Investigations Location and alignment Estimation of scour Protection against scour Backwater Soffit elevation Approach grade elevation Channel erosion control Stream stabilization works and realignment Culverts 31 Section 2 Durability Scope Definitions Design for durability Design concept Durability requirements Structural materials Aluminum Deterioration mechanisms Detailing for durability Polychloroprene and polyisoprene Polytetrafluoroethylene (PTFE) Waterproofing membranes Backfill material Soil and rock anchors Other materials 37. iv November 2006

110 Canadian Highway Bridge Design Code Section 3 Loads Scope Definitions Abbreviations and symbols Abbreviations Symbols Limit states criteria General Ultimate limit states Fatigue limit state Serviceability limit states Load factors and load combinations General Permanent loads Transitory loads Exceptional loads Dead loads Earth loads and secondary prestress loads Earth loads Secondary prestress effects Live loads General Design lanes CL-W loading Application Centrifugal force Braking force Curb load Barrier loads Pedestrian load Maintenance access loads Maintenance vehicle load Multiple-use structures Superimposed deformations General Movements and load effects Superstructure types Temperature effects Wind loads General Design of the superstructure Design of the substructure Aeroelastic instability Wind tunnel tests Water loads General Static pressure Buoyancy Stream pressure Wave action Scour action Debris torrents Ice loads General 67. November 2006 v

111 CAN/CSA-S Dynamic ice forces Static ice forces Ice jams Ice adhesion forces Ice accretion Earthquake effects Vessel collisions General Bridge classification Assessment Annual frequency of collapse Design vessel Application of collision forces Protection of piers Vehicle collision load Construction loads and loads on temporary structures General Dead loads Live loads Segmental construction Falsework 72. Annexes A3.1 (normative) Climatic and environmental data 73 A3.2 (normative) Wind loads on highway accessory supports and slender structural elements 94 A3.3 (normative) Vessel collision 104 A3.4 (normative) CL-625-ONT live loading 113 Section 4 Seismic design Scope Definitions Abbreviation and symbols Abbreviation Symbols Earthquake effects General Importance categories Zonal acceleration ratio Seismic performance zones Analysis for earthquake loads Site effects Elastic seismic response coefficient Response modification factors Load factors and load combinations Design forces and support lengths Analysis General Single-span bridges Multi-span bridges Foundations General Liquefaction of foundation soils Stability of slopes Seismic forces on abutments and retaining walls Soil-structure interaction 135 vi November 2006

112 Canadian Highway Bridge Design Code Fill settlement and approach slabs Concrete structures General Seismic Performance Zone Seismic Performance Zone Seismic Performance Zones 3 and Piles Steel structures General Materials Sway stability effects Steel substructures Other systems Joints and bearings General Seismic design forces Seismic base isolation General Zonal acceleration ratio Seismic performance zones Site effects and site coefficient Response modification factors and design requirements for substructure Analysis procedures Clearance and design displacements for seismic and other loads Design forces for Seismic Performance Zone Design forces for Seismic Performance Zones 2, 3, and Other requirements Required tests of isolation system Elastomeric bearings Design Elastomeric bearings Construction Sliding bearings Design Sliding bearings Construction Seismic evaluation of existing bridges General Bridge classification Damage levels Performance criteria Evaluation methods Load factors and load combinations for seismic evaluation Minimum support length Member capacities Required response modification factor Response modification factor of existing substructure elements Evaluation acceptance criteria Other evaluation procedures Bridge access Liquefaction of foundation soils Soil-structure interaction Seismic rehabilitation Performance criteria Response modification factor for rehabilitation Seismic rehabilitation Seismic rehabilitation techniques 157. November 2006 vii

113 CAN/CSA-S6-06 Section 5 Methods of analysis Scope Definitions Abbreviations and symbols Abbreviations Symbols General requirements Application Analysis for limit states Modelling Structural responses Factors affecting structural responses Deformations Diaphragms and bracing systems Analysis of deck slabs Analysis for redistribution of force effects Analysis for accumulation of force effects due to construction sequence Analysis for effects of prestress Analysis for thermal effects Secondary stability effects Requirements for specific bridge types General Voided slab Limitation on size of voids Deck-on-girder Truss and arch Rigid frame and integral abutment types Transverse wood deck Box girder Single-spine bridges Dead load Simplified methods of analysis (beam analogy method) Refined methods of analysis Live load Simplified methods of analysis Refined methods of analysis Idealization of structure and interpretation of results General Effective flange widths for bending Idealization for analysis Refined methods of analysis for short- and medium-span bridges Selection of methods of analysis Specific applications Model analysis Long-span bridges General Cable-stayed bridges Suspension bridges Dynamic analysis General requirements of structural analysis Elastic dynamic responses Inelastic-dynamic responses Analysis for collision loads Seismic analysis Stability and magnification of force effects 212. viii November 2006

114 Canadian Highway Bridge Design Code General Member stability analysis for magnification of member bending moments Structural stability analysis for lateral sway Structural stability analysis for assemblies of individual members 212 Annexes A5.1 (normative) Factors affecting structural response 213 A5.2 (informative) Two-dimensional analysis 217 Section 6 Foundations Scope Definitions Abbreviations and symbols Abbreviations Symbols Design requirements Limit states Effects on surroundings Effects on structure Components Consultation Inspection and quality control Geotechnical investigation General Investigation procedures Geotechnical parameters Shallow foundations Deep foundations Report Resistance and deformation General Ultimate limit state Serviceability limit state Shallow foundations General Calculated geotechnical resistance at ULS Pressure distribution Effect of load inclination Factored geotechnical horizontal resistance Deep foundations General Selection of deep foundation units Vertical load transfer Downdrag Factored geotechnical axial resistance Group effects Vertical loads Factored geotechnical lateral resistance Structural resistance Embedment and spacing Pile shoes and splices Lateral and vertical pressures General Lateral pressures Compaction surcharge Effects of loads 245. November 2006 ix

115 CAN/CSA-S Surcharge Wheel load distribution through fill Ground anchors Application Design Materials and installation Anchor testing Sheet pile structures Application Design Ties and anchors Cellular sheet pile structures MSE structures Application Design Backfill Pole foundations Application Design 249 Section 7 Buried structures Scope Definitions Abbreviation and symbols Abbreviation Symbols Hydraulic design Structural design Limit states Load factors Material resistance factors Geotechnical considerations Seismic requirements Minimum clear spacing between conduits Soil-metal structures General Structural materials Design criteria Additional design requirements Construction Special features Site supervision and construction control Metal box structures General Structural materials Design criteria Additional design considerations Construction Special features Site supervision and construction control Reinforced concrete buried structures Standards for structural components Standards for joint gaskets for precast concrete units Installation criteria Loads and load combinations 287. x November 2006

116 Canadian Highway Bridge Design Code Earth pressure distribution from loads Analysis Ultimate limit state Strength design Serviceability limit state Fatigue limit state Minimum reinforcement Distribution reinforcement Details of the reinforcement Joint shear for top slab of precast concrete box sections with depth of cover less than 0.6 m Construction 297 Section 8 Concrete structures Scope Definitions Symbols Materials Concrete Reinforcing bars and deformed wire Tendons Anchorages, mechanical connections, and ducts Grout Material resistance factors Limit states General Serviceability limit states Fatigue limit state Ultimate limit states Design considerations General Design Buckling Prestressing Stress limitations for tendons Concrete strength at transfer Grouting Loss of prestress Flexure and axial loads General Assumptions for the serviceability and fatigue limit states Assumptions for the ultimate limit states Flexural components Compression components Tension components Bearing Shear and torsion General Design procedures Sectional design model Slabs, walls, and footings Interface shear transfer Strut-and-tie model General Structural idealization Proportioning of a compressive strut 339. November 2006 xi

117 CAN/CSA-S Proportioning of a tension tie Proportioning of node regions Crack control reinforcement Durability Deterioration mechanisms Protective measures Detailing for durability Control of cracking General Distribution of reinforcement Reinforcement Crack control in the side faces of beams Flanges of T-beams Shrinkage and temperature reinforcement Deformation General Dimensional changes Deflections and rotations Details of reinforcement and special detailing requirements Hooks and bends Spacing of reinforcement Transverse reinforcement for flexural components Transverse reinforcement for compression components Reinforcement for shear and torsion Maximum spacing of reinforcement for shear and torsion Development and splices Development Development of reinforcing bars and deformed wire in tension Development of reinforcing bars in compression Development of pretensioning strand Development of standard hooks in tension Combination development length Development of welded wire fabric in tension Mechanical anchorages Splicing of reinforcement Anchorage zone reinforcement General Post-tensioning anchorage zones Pretensioning anchorage zones Inclined anchorages Intermediate anchorages Anchorage blisters Anchorage of attachments Seismic design and detailing Special provisions for deck slabs Design methods Minimum slab thickness Allowance for wear Empirical design method Diaphragms Edge stiffening Distribution reinforcement Composite construction General 372. xii November 2006

118 Canadian Highway Bridge Design Code Flexure Shear Semi-continuous structures Concrete girders General Effective flange width for T- and box girders Flange thickness for T- and box girders Isolated girders Top and bottom flange reinforcement for cast-in-place T- and box girders Post-tensioning tendons Diaphragms Multi-beam decks Segmental construction General Additional ducts and anchorages Diaphragms Deviators for external tendons Coupling of post-tensioning tendons Special provisions for various bridge types Precast segmental beam bridges Concrete piles General Specified concrete strength Handling Splices Pile dimensions Non-prestressed concrete piles Prestressed concrete piles 379. Section 9 Wood structures Scope Definitions Symbols Limit states General Serviceability limit states Ultimate limit states Resistance factor General design Design assumption Spans Load-duration factor Size-effect factors Service condition Load-sharing factor Notched components Butt joint stiffness factor Treatment factor Flexure Flexural resistance Size effect Lateral stability Shear Shear resistance Size effect 392 November 2006 xiii

119 CAN/CSA-S Shear force and shear load Shear modulus Vertically laminated decks Compression members General Compressive resistance parallel to grain Slenderness effect Amplified moments Rigorous evaluation of amplified moments Approximate evaluation of amplified moments Tension members Compression at an angle to grain Sawn wood Materials Specified strengths and moduli of elasticity Glued-laminated timber Materials Specified strengths and moduli of elasticity Vertically laminated beams Camber Varying depth Curved members Structural composite lumber Materials Specified strengths and moduli of elasticity Wood piles Materials Splicing Specified strengths and moduli of elasticity Design Fastenings General Design Construction Hardware and metalwork Durability General Pedestrian contact Incising Fabrication Pressure preservative treatment of laminated veneer lumber Pressure preservative treatment of parallel strand lumber Field treatment Treated round wood piles Untreated round wood piles Pile heads Protective treatment of hardware and metalwork Stress-laminated timber decking Wood cribs General Member sizes and assembly Fastening Load transfer to cribs Wood trestles 411. xiv November 2006

120 Canadian Highway Bridge Design Code General Pile bents Framed bents Caps Bracing Stringers and girders Design details Diaphragms Nail-laminated wood decks General Transversely laminated wood decks Longitudinal nail-laminated wood decks Wood-concrete composite decks General Wood base Concrete slab Wood-concrete interface Factored moment resistance Stress-laminated wood decks General Post-tensioning materials Design of post-tensioning system Design of distribution bulkhead Laminated decks Net section Hardware durability Design details Wearing course Drainage General Deck 424. Section 10 Steel structures Scope Definitions Abbreviations and symbols Abbreviations Symbols Materials General Structural steel Cast steel Stainless steel Bolts Welding electrodes Stud shear connectors Cables High-strength bars Galvanizing and metallizing Identification Coefficient of thermal expansion Design theory and assumptions General Ultimate limit states Serviceability limit states 438 November 2006 xv

121 CAN/CSA-S Fatigue limit state Fracture control Seismic requirements Resistance factors Analysis Design lengths of members Durability General Corrosion as a deterioration mechanism Corrosion protection Superstructure components Other components Areas inaccessible after erection Detailing for durability Design detail General Minimum thickness of steel Floor beams and diaphragms at piers and abutments Camber Welded attachments Tension members General Axial tensile resistance Axial tension and bending Tensile resistance of cables Compression members General Width-to-thickness ratio of elements in compression Axial compressive resistance Axial compression and bending Composite columns Beams and girders General Class 1 and 2 sections Class 3 sections Stiffened plate girders Shear resistance Intermediate transverse stiffeners Longitudinal web stiffeners Bearing stiffeners Lateral bracing, cross-frames, and diaphragms Composite beams and girders General Proportioning Effects of creep and shrinkage Control of permanent deflections Class 1 and Class 2 sections Class 3 sections Stiffened plate girders Shear connectors Lateral bracing, cross-frames, and diaphragms Composite box girders General Effective width of tension flanges 471. xvi November 2006

122 Canadian Highway Bridge Design Code Web plates Flange-to-web welds Moment resistance Diaphragms, cross-frames, and lateral bracing Multiple box girders Single box girders Horizontally curved girders General Special considerations Design theory Bearings Diaphragms, cross-frames, and lateral bracing Steel I-girders Composite box girders Camber Trusses General Built-up members Bracing Arches General Width-to-thickness ratios Longitudinal web stiffeners Axial compression and bending Arch ties Orthotropic decks General Effective width of deck Superposition of local and global effects Deflection Girder diaphragms Design detail requirements Wearing surface Structural fatigue General Live-load-induced fatigue Distortion-induced fatigue Orthotropic decks Splices and connections General Bolted connections Welds Detailing of bolted connections Connection reinforcement and stiffening Anchors General Anchor bolt resistance Pins, rollers, and rockers Bearing resistance Pins Torsion General Members of closed cross-section Members of open cross-section 512. November 2006 xvii

123 CAN/CSA-S Piles Steel piles Effective length Splices Composite tube piles Fracture control General Identification Fracture toughness Welding of fracture-critical and primary tension members Welding corrections and repairs to fracture-critical members Non-destructive testing of fracture-critical members Construction requirements for structural steel General Submissions Materials Fabrication Welded construction Bolted construction Tolerances Quality control Transportation and delivery Erection 529. Section 11 Joints and bearings Scope Definitions Abbreviations and symbols Abbreviations Symbols Common requirements General Design requirements Deck joints General requirements Selection Design Fabrication Installation Joint seals Sealed joint drainage Open joint drainage Volume control joint Bridge bearings General Metal back, roller, and spherical bearings Sliding surfaces Spherical bearings Pot bearings Elastomeric bearings Disc bearings Guides for lateral restraints Other bearing systems Load plates and attachment for bearings 550 xviii November 2006

124 Canadian Highway Bridge Design Code Section 12 Barriers and highway accessory supports Scope Definitions Abbreviations and symbols Abbreviations Symbols Barriers General Barrier joints Traffic barriers Pedestrian barriers Bicycle barriers Combination barriers Highway accessory supports General Vertical clearances Maintenance Aesthetics Design Breakaway supports Foundations Corrosion protection Minimum thicknesses Camber Connections 567. Section 13 Movable bridges Scope Definitions Symbols Materials General Structural steel Concrete Timber Carbon steel Forged steel Cast steel or iron Bronze Bolts Wire rope General design requirements General Type of deck Piers and abutments Navigation requirements Vessel collision Protection of traffic Fire protection Time of operation Aligning and locking Houses for machinery, electrical equipment, and operators New devices Access for routine maintenance Durability 576 November 2006 xix

125 CAN/CSA-S Movable bridge components General features Swing bridge components Bascule bridge components Rolling lift bridge components Vertical lift bridge components Structural analysis and design General Design theory and assumptions Wind loads Seismic loads Reaction due to temperature differential Hydraulic cylinder connections Loads on end floor beams and stringer brackets Swing bridges Ultimate limit states Bascule (including rolling lift) bridges Ultimate limit states Vertical lift bridges Ultimate limit states Dead load factor All movable bridges Ultimate limit states Special types of movable bridges Load effects Fatigue limit state Friction Machinery supports Vertical lift bridge towers Transitory loads Mechanical system design General Operating machinery Power sources Prime mover Power requirements for main machinery Wedges Brakes Frictional resistance Torque Application of worker power Machinery loads Allowable stresses for machinery and allowable hydraulic pressures Bearing pressures (moving surfaces) Line-bearing pressure Design of wire ropes Shafting Machinery fabrication and installation Lubrication Power equipment Quality of work Hydraulic system design Electrical system design General Canadian Electrical Code, Part I General requirements for electrical installation Working drawings Motor and generator tests 620. xx November 2006

126 Canadian Highway Bridge Design Code Motors General requirements Motor torque for span operation Motor temperature, insulation, and service factor Number of motors Synchronizing motors for tower-drive vertical lift bridges Speed of motors Gear motors Engine-generator sets Automatic electric power transfer Electrically operated motor brakes Electrically operated machinery brakes Design of electrical parts Electrical control Speed control for span-driving motors Master switches and relays for span-driving motors Programmable logic controllers Resistances and reactors Limit switches Interlocking Switches Circuit breakers and fuses Contact areas Magnetic contactors Overload relays Shunt coils Instruments Protection of electrical equipment Cast iron in electrical parts Position indicators and meters Indicating lights Control console Control panels Enclosures for panel boards Electrical wires and cables Tagging of wires Wire splices and connections Raceways, metal conduits, conduit fittings, and boxes Electrical connections between fixed and moving parts Electrical connections across the navigable channel Service lights Navigation lights Aircraft warning lights Circuits Grounding and lightning protection Spare parts Construction Shop assemblies Coating Erection Training and start-up assistance Operating and maintenance manual Inspection 640. November 2006 xxi

127 CAN/CSA-S6-06 Section 14 Evaluation Scope Definitions Symbols General requirements Exclusions Expertise Future growth of traffic or future deterioration Evaluation procedures General Limit states Condition data Procedures Bridge posting Condition inspection General Plans Physical features Deterioration Material strengths General Review of original construction documents Analysis of tests of samples Strengths based on date of construction Deteriorated material Permanent loads General Dead load Earth pressure and hydrostatic pressure Shrinkage, creep, differential settlement, and bearing friction Secondary effects from prestressing Transitory loads Normal traffic Permit Vehicle loads Dynamic load allowance for permit vehicle loads and alternative loading Multiple-lane loading Loads other than traffic Exceptional loads Lateral distribution categories for live load General Statically determinate method Sophisticated method Simplified method Target reliability index General System behaviour Element behaviour Inspection level Important structures Load factors General Permanent loads Transitory loads Resistance 665. xxii November 2006

128 Canadian Highway Bridge Design Code General Resistance adjustment factor Effects of defects and deterioration Live load capacity factor General Ultimate limit states Serviceability limit states Combined load effects Load testing General Instrumentation Test load Application of load test results Bridge posting General Calculation of posting loads Posting signs Fatigue 679. Annexes A14.1 (normative) Equivalent material strengths from tests of samples 680 A14.2 (normative) Evaluation Level 1 (vehicle trains) in Ontario 682 A14.3 (normative) Evaluation Level 2 (two-unit vehicles) in Ontario 683 A14.4 (normative) Evaluation Level 3 (single-unit vehicles) in Ontario 684 Section 15 Rehabilitation and repair Scope Symbols General requirements Limit states Condition data Rehabilitation loads and load factors Analysis Factored resistances Fatigue Bridge posting Seismic upgrading Special considerations Data collection Rehabilitation loads and load factors Loads Load factors and load combinations Analysis Resistance Existing members New members 692 Section 16 Fibre-reinforced structures Scope Components Fibres Matrices Uses requiring Approval Definitions Abbreviations and symbols 697 November 2006 xxiii

129 CAN/CSA-S Abbreviations Symbols Durability FRP tendons, primary reinforcement, and strengthening systems FRP secondary reinforcement Fibres in FRC Cover to reinforcement Protective measures Allowance for wear in deck slabs Detailing of concrete components for durability Handling, storage, and installation of fibre tendons and primary reinforcement Fibre-reinforced polymers Material properties Confirmation of the specified tensile strength Resistance factor Fibre-reinforced concrete General Fibre volume fraction Fibre dispersion in concrete Externally restrained deck slabs General Full-depth cast-in-place deck slabs Cast-in-place deck slabs on stay-in-place formwork Full-depth precast concrete deck slabs Concrete beams and slabs General Deformability and minimum reinforcement Non-prestressed reinforcement Development length for FRP bars and tendons Development length for FRP grids Tendons Design for shear Internally restrained cast-in-place deck slabs Stressed wood decks General Post-tensioning materials Post-tensioning system Stressing procedure Design of bulkheads Stressed log bridges Barrier walls Rehabilitation of existing concrete structures with FRP General Flexural and axial load rehabilitation Shear rehabilitation with externally bonded FRP systems Rehabilitation of timber bridges General Strengthening for flexure Strengthening for shear 726. Annexes A16.1 (normative) Installation of FRP strengthening systems 729 A16.2 (normative) Quality control for FRP strengthening systems 732 xxiv November 2006

130 Canadian Highway Bridge Design Code Tables 1.1 Highway classes Load factors and load combinations Permanent loads Maximum and minimum values of load factors for ULS Unit material weights Number of design lanes Modification factor for multi-lane loading Loads on traffic barriers Maximum and minimum effective temperatures Wind exposure coefficient, C e Modification of wind loads on superstructure with skew angle Longitudinal drag coefficient, C D Lateral load coefficient, C L Seismic performance zones Minimum analysis requirements for multi-span bridges Regular bridge requirements Site coefficient, S Response modification factor, R Modification factor, K Site coefficient for seismic isolation design, S i Damping coefficient, B Minimum analysis requirements for evaluation Structural responses Superstructure categories for simplified methods of analysis for live load F and C f for longitudinal bending moments in shallow superstructures corresponding to ultimate and serviceability limit states F and C f for longitudinal bending moments in shallow superstructures corresponding to the fatigue limit state C e for longitudinal bending moments in shallow superstructures corresponding to the fatigue and vibration limit state F and C f for longitudinal moments in multi-spine bridges F for longitudinal vertical shear corresponding to ultimate and serviceability limit states, m F for longitudinal vertical shear corresponding to fatigue limit state, m F for longitudinal vertical shear in multi-spine bridges Maximum cantilever moments, M y, due to unfactored CL-625 Truck wheel loads (DLA included), kn m/m Effective deck plate width for a longitudinal rib Selection of methods of analysis Geotechnical resistance factors Equivalent fluid pressure per metre width, kpa/m Requirements for cut ends Specific limit states Material resistance factors Soil classifications Secant modulus of soil, E s, for various soils Values for k 4 for calculating equivalent line loads Minimum transverse distance of backfill in single-conduit soil-metal structures Standards for precast buried concrete structures Classification of placed soils Soils and compaction requirements for standard installations for circular precast concrete pipes Soils and compaction requirements for standard installations for concrete boxes Vertical and horizontal arching factors for circular concrete pipes in standard installations Vertical and horizontal arching factors for box sections in standard installations 288. November 2006 xxv

131 CAN/CSA-S Force factors for earth loads Earth pressure factors Length factors for earth pressures Crack-control coefficient, C Shrinkage and temperature reinforcement Material resistance factors Prestressing tendon stress limits Friction factors Maximum water to cementing materials ratio Minimum concrete covers and tolerances Maximum crack width Minimum bend diameter, mm Minimum development length of reinforcing bars and deformed wire in tension Modification factors for development length Modification factors for hook development length Classification of lap splices in tension Construction tolerances Resistance factor for wood components, φ Load-sharing factor for bending, shear, and tension for all species and grades Values of D e Size-effect factors k sb for flexure and k sv for shear for all species and grades Modification factor for lateral stability, k ls Minimum values of the effective length factor, k A, S, and e o for piles at 0.55 of the effective length below the butt joint η to be used in calculating P cr for piles Size-effect factor, k st, for tension at net section in dimension lumber Size-effect factor for bearing, k sq Permitted species and species combinations for sawn wood Specified strengths and moduli of elasticity for structural joists and planks, MPa Specified strengths and moduli of elasticity for beam and stringer grades, MPa Specified strengths and moduli of elasticity for post and timber grades, MPa Specified strengths and moduli of elasticity for glued-laminated Douglas fir timber, MPa Typical specified strengths and moduli of elasticity for structural composite lumber, MPa Specified strengths and moduli of elasticity for round wood piles, MPa Limiting pressure perpendicular to grain, f ql, MPa Minimum section properties for steel channel bulkheads Corrosion protection for superstructure components Corrosion protection for other components Width-to-thickness ratio of elements in compression Fatigue life constants and constant amplitude threshold stress ranges Values of N d Average daily truck traffic Detail categories for load-induced fatigue Detail categories for load-induced fatigue of orthotropic decks Values of k s and c Matching electrode classifications for CSA G40.21 and CSA W59 steels Minimum edge distance for bolt holes Impact test temperatures and Charpy impact energy requirements for fracture-critical members Impact test temperatures and Charpy impact energy requirements for primary tension members Impact test temperatures and Charpy impact energy requirements for weld metal Preheat and interpass temperature for steel grades Minimum elapsed time for acceptance testing 519. xxvi November 2006

132 Canadian Highway Bridge Design Code Minimum bend radii for bent plates Nut rotation from snug-tight condition Facing of bearing surfaces roughness requirements Dimensions for confined sheet PTFE Dimensions for stainless steel Maximum average contact pressure for PTFE, MPa Design coefficient of friction Physical properties of polyisoprene and polychloroprene Highway type factors, K h Highway curvature factors, K c Highway grade factors, K g Superstructure height factors, K s Optimum performance levels Barrier clearance less than or equal to 2.25 m Optimum performance levels Barrier clearance greater than 2.25 m and less than or equal to 3.75 m Optimum performance levels Barrier clearance greater than 3.75 m Minimum barrier heights, H Strengths for aluminum castings Maximum tensile strength for Grade 1770 bright wire Maximum tensile strength for Grade 110/120 bright wire Swing bridges Special load combinations and load factors Bascule (including rolling lift) bridges Special load combinations and load factors Vertical lift bridges Special load combinations and load factors Dead load factor, α D Coefficients of friction Machinery losses and efficiency coefficients Coefficients of friction for sliding span locks and end and centre wedges Maximum allowable stresses in trunnions, MPa (psi) Maximum allowable stresses for machinery parts other than trunnions, MPa (psi) Maximum bearing pressures Ultimate stress and ultimate strength of steel wire rope of 6 19 classification and 6 25 filler construction Permissible stresses in gear teeth Fits and finishes Properties of structural steel Minimum yield strengths of reinforcing steel, MPa Modification factors for multiple-lane loading Fraction of CL1-W loading to be applied in the other lanes Target reliability index, β, for normal traffic and for PA, PB, and PS traffic Target reliability index, β, for PC traffic Maximum dead load factors, α D Live load factors, α L, for normal traffic (Evaluation Levels 1, 2, and 3) for all types of analysis Live load factors, α L, for normal traffic (alternative loading) for all types of analysis Live load factors, α L, for PA traffic Live load factors, α L, for PB traffic Live load factors, α L, for PC traffic Live load factors, α L, for PS traffic Specified strengths and moduli of elasticity for beam and stringer grades and post and timber grades, MPa Resistance adjustment factor, U Rehabilitation design live loads for restricted normal traffic Conditions of use for FRP tendons and primary reinforcement φ FRP for pultruded FRP and aramid fibre rope Minimum values of R i for various applications 704. November 2006 xxvii

133 CAN/CSA-S Maximum permissible stresses in FRP tendons at jacking and transfer for concrete beams and slabs for pretensioning and post-tensioning systems Values of K bfrp 725 Figures 3.1 Deflection limits for highway bridge superstructure vibration CL-W Truck CL-W Lane Load Maintenance vehicle load Modifications to maximum and minimum effective temperatures Temperature differentials for Type A and C superstructures Pier nose angle and subtended nose angle for calculating forces due to moving ice Dimensions for minimum support lengths D VE for slab-on-girder bridges Calculation of A Notation for cantilever moments Values of k for calculating transverse vertical shear in shear-connected beam bridges b e and b for various cross-sections Effective width of orthotropic deck Failure mechanism for footing Footing under eccentric load Bearing coefficients Eccentricity limit Load inclination reduction factors for bearing resistance, φ = Compaction effects D h and D v for various shapes of pipe Values of A f Depth of cover, H and H min, for soil-metal structures and metal box structures Trench reinforcement for the foundation of pipe-arches Longitudinal seam bolting arrangements Metal box structure dimensional limits Minimum extent of structural backfill for metal box structures Terminology and standard installations for circular precast concrete pipes on embankments Terminology and standard installations for circular precast concrete pipes in trenches Standard installations for concrete box sections on embankments Standard installations for concrete box sections in trenches Earth pressure distribution for standard installations of circular concrete pipes (force diagram) Lateral earth loads and pressure distribution on concrete box sections due to approaching wheel loads Magnitude of thrust Eccentricity of curved tendons Influence of reinforcement on spacing of diagonal cracks Influence of anchorage conditions on effective cross-sectional area of strut Reinforcement in cast-in-place deck slab Reinforcement for cast-in-place deck slabs designed using the empirical method Reinforcement for cast-in-place deck slabs on precast panels Edge stiffening at transverse free edges Connection of nail-laminated deck to steel beam Spliced butt joint Details of wood-concrete interface Alternative details of wood-concrete interface External post-tensioning system Internal post-tensioning system Protection for external post-tensioning system 423. xxviii November 2006

134 Canadian Highway Bridge Design Code 10.1 Class 1 and 2 sections in positive moment regions Class 1 and 2 sections in negative moment regions Class 3 Sections in positive moment regions Class 3 Sections in negative moment regions Detailing requirements for orthotropic decks Detail categories for load-induced fatigue Maximum average pressure on a layer of elastomeric bearing at SLS without rotation Application of traffic design loads to traffic barriers Application of pedestrian and bicycle design loads to barriers Level 1 evaluation loads with CL1-W Truck Level 2 evaluation loads with CL2-W Truck Level 3 evaluation loads with CL3-W Truck Deck punching shear for composite slabs Deck punching shear for non-composite slabs Spacing requirements for minimum reinforcement, mm Spacing requirements for minimum reinforcement as a fraction of shear depth Posting loads for gross vehicle weight Distance between the deck slab and the top of the supporting beam Detail of transverse edge stiffening Detail of transverse edge stiffening Detail of transverse edge stiffening Detail of transverse edge stiffening External transverse restraining system consisting of connected straps External transverse confining system consisting of indirectly connected partially studded straps External transverse confining system in longitudinal negative moment regions Post-tensioning system for stressed log bridges Spliced butt joint for logs Cross-section of a barrier wall reinforced with GFRP Anchorage methods in the compression zone of externally bonded FRP shear reinforcement Cross-section of a timber beam with GFRP NSMR Elevation of timber beam with GFRP sheets for shear strengthening Elevation of timber beam with GFRP bars for shear strengthening 728. November 2006 xxix

135 CAN/CSA-S6-06 Technical Committee on the Canadian Highway Bridge Design Code J. Francis Nova Scotia Department of Transportation and Public Works, Halifax, Nova Scotia B. Bakht JMBT Structures Research Inc., Toronto, Ontario G. Richard Ministère des transports du Québec, Québec, Québec Chair Vice-Chair Vice-Chair. T.B. Tharmabala Ontario Ministry of Transportation, St. Catharines, Ontario Vice-Chair H. Yea Saskatchewan Highways and Transportation, Regina, Saskatchewan Vice-Chair A.C. Agarwal W.V. Anderson Brampton, Ontario Delcan Corporation, Markham, Ontario D. Bagnariol Ontario Ministry of Transportation, St. Catharines, Ontario N. Banthia University of British Columbia, Vancouver, British Columbia Associate Associate F.M. Bartlett University of Western Ontario, London, Ontario D. Beaulieu Centre de recherche industrielle du Québec, Ste-Foy, Québec G.P. Carlin M.S. Cheung Les Ponts Jacques Cartier et Champlain Incorporée, Longueuil, Québec University of Ottawa, Ottawa, Ontario Associate C. Clarke Alberta Infrastructure and Transportation, Edmonton, Alberta D. Cogswell New Brunswick Department of Transportation, Fredericton, New Brunswick Associate xxx November 2006

136 Canadian Highway Bridge Design Code D. Dundas Ontario Ministry of Transportation, Toronto, Ontario D.J. Evans Prince Edward Island Department of Transportation and Public Works, Charlottetown, Prince Edward Island P. Gauvreau University of Toronto, Toronto, Ontario A. Ho Ontario Ministry of Transportation, Toronto, Ontario K.C. Johns Université de Sherbrooke, Sherbrooke, Québec C. Lam Ontario Ministry of Transportation, St. Catharines, Ontario P. Lepper Canadian Wood Council, Ottawa, Ontario Associate Associate. D. Macleod Public Works and Government Services Canada, Gatineau, Québec B. Massicotte École Polytechnique de Montréal, Montréal, Québec R. Mathieson British Columbia Ministry of Transportation, Victoria, British Columbia R.J. McGrath Cement Association of Canada, Ottawa, Ontario D. Mitchell McGill University, Montréal, Québec A.A. Mufti University of Manitoba, Winnipeg, Manitoba A. Nelson Manitoba Department of Highways and Transportation, Winnipeg, Manitoba R.J. Ramsay J.A. Skeet A.F. Wong UMA Engineering Limited, Edmonton, Alberta Dillon Consulting Limited, Calgary, Alberta Canadian Institute of Steel Construction, Toronto, Ontario Associate Associate M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xxxi

137 CAN/CSA-S6-06 Subcommittee on Section 1 General A. Ho Ontario Ministry of Transportation, Toronto, Ontario J. Doering University of Manitoba, Winnipeg, Manitoba H. Farghaly Ontario Ministry of Transportation, St. Catharines, Ontario R. Haynes Ontario Ministry of Transportation, St. Catharines, Ontario R. Richardson Manitoba Department of Highways and Transportation, Winnipeg, Manitoba Chair. D.M. Tran Ministère des transports du Québec, Québec, Québec R. Walters Stantec Consulting Limited, Edmonton, Alberta E. Waschuk Alberta Infrastructure and Transportation, Edmonton, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager xxxii November 2006

138 Canadian Highway Bridge Design Code Subcommittee on Section 2 Durability N. Banthia University of British Columbia, Vancouver, British Columbia G.E. Brudermann P.D. Carter Frido Consulting, Halfmoon Bay, British Columbia CH2M HILL Canada, Vancouver, British Columbia D. Conte Ontario Ministry of Transportation, Toronto, Ontario O.E. Gjorv Norwegian University of Science and Technology, Trondheim, Norway Chair. J. Kroman City of Calgary, Calgary, Alberta Z. Lounis National Research Council Canada, Ottawa, Ontario P. McGrath McGrath Engineering Ltd., North Vancouver, British Columbia S. Mindess University of British Columbia, Vancouver, British Columbia K. Sakai Kagawa University, Takamatsu, Japan G. Tadros STECO Engineering Ltd., Calgary, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xxxiii

139 CAN/CSA-S6-06 Subcommittee on Section 3 Loads A.C. Agarwal Brampton, Ontario Chair A. Au Ontario Ministry of Transportation, St. Catharines, Ontario D.P. Gagnon J.P. Grenier Buckland & Taylor Ltd., North Vancouver, British Columbia Ministère des transports du Québec, Québec, Québec P. King University of Western Ontario, London, Ontario C. Lam Ontario Ministry of Transportation, St. Catharines, Ontario. D. Mitchell McGill University, Montréal, Québec R.H. Pion Public Works and Government Services Canada, Gatineau, Québec G. Van Der Vinne Northwest Hydraulic Consultants Ltd., Edmonton, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager xxxiv November 2006

140 Canadian Highway Bridge Design Code Subcommittee on Section 4 Seismic design D. Mitchell McGill University, Montréal, Québec M.U. Atukorala Golder Associates Ltd., Burnaby, British Columbia D. Bagnariol Ontario Ministry of Transportation, St. Catharines, Ontario M. Bruneau University at Buffalo, Buffalo, New York, USA A. Heidebrecht McMaster University, Hamilton, Ontario Chair. D. Kennedy Associated Engineering Ltd., Burnaby, British Columbia N. Theodor Ontario Ministry of Transportation, St. Catharines, Ontario R. Tremblay École Polytechnique de Montréal, Montréal, Québec S. Zhu Buckland & Taylor Ltd., North Vancouver, British Columbia M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xxxv

141 CAN/CSA-S6-06 Subcommittee on Section 5 Methods of analysis B. Massicotte École Polytechnique de Montréal, Montréal, Québec J. Au Ontario Ministry of Transportation, St. Catharines, Ontario T. Chicoine SNC-Lavalin Inc., Montréal, Québec J.P. Grenier Ministère des transports du Québec, Québec, Québec J. Newhook Dalhousie University, Halifax, Nova Scotia Chair. S. Sabanathan Ontario Ministry of Transportation, St. Catharines, Ontario M. Talbot Ministère des transports du Québec, Québec, Québec M. Braiter CSA, Mississauga, Ontario Project Manager xxxvi November 2006

142 Canadian Highway Bridge Design Code Subcommittee on Section 6 Foundations D. Dundas Ontario Ministry of Transportation, Toronto, Ontario A. Altaee Urkkada Technology, Ottawa, Ontario M.U. Atukorala Golder Associates Ltd., Burnaby, British Columbia P. Branco Thurber Engineering Limited, Oakville, Ontario G. Fenton Dalhousie University, Halifax, Nova Scotia Chair. R. Green Waterloo, Ontario I. Husain Ontario Ministry of Transportation, St. Catharines, Ontario I. Leclerc Ministère des transports du Québec, Québec, Québec P. Ojala Lea Consulting Limited, Markham, Ontario D. Woeller ConeTec Investigations Ltd., Vancouver, British Columbia M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xxxvii

143 CAN/CSA-S6-06 Subcommittee on Section 7 Buried structures B. Bakht JMBT Structures Research Inc., Toronto, Ontario G. Abdel-Sayed Bloomfield Hills, Michigan, USA J. Au Ontario Ministry of Transportation, St. Catharines, Ontario K. Bontius Hatch, Mott & MacDonald, Mississauga, Ontario W. Brockbank Reinforced Earth Company Ltd., Mississauga, Ontario Chair. M. Gergely Ontario Ministry of Transportation, St. Catharines, Ontario W. Kenedi Ontario Ministry of Transportation, St. Catharines, Ontario E. Kling Centennial Concrete Pipe & Products Inc., Cambridge, Ontario I. Leclerc Ministère des transports du Québec, Québec, Québec J. Meyboom Delcan Corporation, New Westminster, British Columbia C. Mirza Toronto, Ontario I. Moore Queen s University, Kingston, Ontario T. Morrison Atlantic Industries Limited, Cambridge, Ontario J. Newhook Dalhousie University, Halifax, Nova Scotia P. Sheehan Armtec Limited Partnership, Guelph, Ontario M. Braiter CSA, Mississauga, Ontario Project Manager xxxviii November 2006

144 Canadian Highway Bridge Design Code Subcommittee on Section 8 Concrete structures P. Gauvreau University of Toronto, Toronto, Ontario D. Bernard Ministère des transports du Québec, Québec, Québec M.P. Collins University of Toronto, Toronto, Ontario H. Ibrahim Buckland & Taylor Ltd., North Vancouver, British Columbia W. Leblanc Con-Force Structures Limited, Calgary, Alberta Chair. R.J. McGrath Cement Association of Canada, Ottawa, Ontario M. Meleka Ontario Ministry of Transportation, St. Catharines, Ontario D.M. Rogowsky UMA Engineering Ltd., Edmonton, Alberta R. Stofco McCormick Rankin Corporation, Mississauga, Ontario M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xxxix

145 CAN/CSA-S6-06 Subcommittee on Section 9 Wood structures K.C. Johns Université de Sherbrooke, Sherbrooke, Québec B. Bakht JMBT Structures Research Inc., Toronto, Ontario L.M. Bélanger R.M.G. Britton G.E. Brudermann Ministère des transports du Québec, Québec, Québec University of Manitoba, Winnipeg, Manitoba Frido Consulting, Halfmoon Bay, British Columbia Chair. R.J. Eden Manitoba Floodway Authority, Winnipeg, Manitoba M. Erki Royal Military College of Canada, Kingston, Ontario R.O. Foschi University of British Columbia, Vancouver, British Columbia R. Krisciunas Ontario Ministry of Transportation, Thunder Bay, Ontario P. Lepper Canadian Wood Council, Ottawa, Ontario I. Sturrock British Columbia Ministry of Transportation, Victoria, British Columbia M. Braiter CSA, Mississauga, Ontario Project Manager xl November 2006

146 Canadian Highway Bridge Design Code Subcommittee on Section 10 Steel structures D. Beaulieu Centre de recherche industrielle du Québec, Ste-Foy, Québec D. Francis Supreme Steel Ltd., Edmonton, Alberta G. Grondin University of Alberta, Edmonton, Alberta H. Hawk Delcan Corporation, Calgary, Alberta J. Labbé Ministère des transports du Québec, Québec, Québec Chair. N. Theodor Ontario Ministry of Transportation, St. Catharines, Ontario R. Vincent Canam Group Inc., Boucherville, Québec A.F. Wong Canadian Institute of Steel Construction, Toronto, Ontario M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xli

147 CAN/CSA-S6-06 Subcommittee on Section 11 Joints and bearings J.A. Skeet Dillon Consulting Limited, Calgary, Alberta J. Labbé Ministère des transports du Québec, Québec, Québec R. Mihaljevic Ontario Ministry of Transportation, St. Catharines, Ontario N. Patel Ontario Ministry of Transportation, St. Catharines, Ontario J.F. Reysset Goodco Ltée, Laval, Québec Chair. R. Yu Alberta Infrastructure and Transportation, Edmonton, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager xlii November 2006

148 Canadian Highway Bridge Design Code Subcommittee on Section 12 Barriers and highway accessory supports R.J. Ramsay UMA Engineering Limited, Edmonton, Alberta D. Beaulieu Centre de recherche industrielle du Québec, Ste-Foy, Québec M. Blouin Ministère des transports du Québec, Québec, Québec R. Haynes Ontario Ministry of Transportation, St. Catharines, Ontario Chair. M. Vallières Ministère des transports du Québec, Québec, Québec R. Yu Alberta Infrastructure and Transportation, Edmonton, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xliii

149 CAN/CSA-S6-06 Subcommittee on Section 13 Movable bridges T.B. Tharmabala Ontario Ministry of Transportation, St. Catharines, Ontario D. Campbell Klohn-Krippen Consultants Ltd., Vancouver, British Columbia R. Clayton Byrne Engineering Inc., Burlington, Ontario J. Crabb Delcan Corporation, Markham, Ontario D. Dixon McCormick Rankin Corporation, Mississauga, Ontario Chair. L. Huang Modjeski and Masters, Mechanicsburg, Pennsylvania, USA Q. Islam Ontario Ministry of Transportation, Kingston, Ontario W. McCraken Byrne Engineering Inc., Burlington, Ontario J. Saweczko Byrne Engineering Inc., Burlington, Ontario P.M. Skelton Hardesty & Hanover, New York, New York, USA A. Zaki SNC-Lavalin Inc., Montréal, Québec M. Braiter CSA, Mississauga, Ontario Project Manager xliv November 2006

150 Canadian Highway Bridge Design Code Subcommittee on Section 14 Evaluation D. Bagnariol Ontario Ministry of Transportation, St. Catharines, Ontario F.M. Bartlett D.P. Gagnon J.P. Grenier University of Western Ontario, London, Ontario Buckland & Taylor Ltd., North Vancouver, British Columbia Ministère des transports du Québec, Québec, Québec B. Higgins CBCL Limited, Halifax, Nova Scotia Chair. W. Kenedi Ontario Ministry of Transportation, St. Catharines, Ontario C. Lam Ontario Ministry of Transportation, St. Catharines, Ontario J. Meyboom Delcan Corporation, New Westminster, British Columbia P. Ojala Lea Consulting Limited, Markham, Ontario R.J. Ramsay UMA Engineering Limited, Edmonton, Alberta M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xlv

151 CAN/CSA-S6-06 Subcommittee on Section 15 Rehabilitation and repair F.M. Bartlett University of Western Ontario, London, Ontario D. Dixon McCormick Rankin Corporation, Mississauga, Ontario L. Feldman University of Saskatchewan, Saskatoon, Saskatchewan D.P. Gagnon Buckland & Taylor Ltd., North Vancouver, British Columbia D. Lai Ontario Ministry of Transportation, St. Catharines, Ontario Chair. K.W. Neale Université de Sherbrooke, Sherbrooke, Québec M. Braiter CSA, Mississauga, Ontario Project Manager xlvi November 2006

152 Canadian Highway Bridge Design Code Subcommittee on Section 16 Fibre-reinforced structures A.A. Mufti University of Manitoba, Winnipeg, Manitoba B. Bakht JMBT Structures Research Inc., Toronto, Ontario N. Banthia University of British Columbia, Vancouver, British Columbia B. Benmokrane Université de Sherbrooke, Sherbrooke, Québec G. Desgagné Ministère des transports du Québec, Québec, Québec Chair. R.J. Eden Manitoba Floodway Authority, Winnipeg, Manitoba M. Erki Royal Military College of Canada, Kingston, Ontario V. Karbhari University of California at San Diego, La Jolla, California, USA J. Kroman City of Calgary, Calgary, Alberta D. Lai Ontario Ministry of Transportation, St. Catharines, Ontario A. Machida Saitama University, Urawa, Japan K.W. Neale Université de Sherbrooke, Sherbrooke, Québec G. Tadros STECO Engineering Ltd., Calgary, Alberta B. Taljsten BYG-DTU, Lyngby, Denmark M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 xlvii

153 CAN/CSA-S6-06 Code Calibration Task Force A.C. Agarwal Brampton, Ontario Chair A. Au Ontario Ministry of Transportation, St. Catharines, Ontario D. Becker Golder Associates Ltd., Calgary, Alberta R.O. Foschi D.P. Gagnon University of British Columbia, Vancouver, British Columbia Buckland & Taylor Ltd., North Vancouver, British Columbia H. Hong University of Western Ontario, London, Ontario. P. King University of Western Ontario, London, Ontario C. Lam Ontario Ministry of Transportation, St. Catharines, Ontario D. Mitchell McGill University, Montréal, Québec A.S. Nowak University of Nebraska, Lincoln, Nebraska, USA M. Braiter CSA, Mississauga, Ontario Project Manager xlviii November 2006

154 Canadian Highway Bridge Design Code Editorial Task Force M. Erki Royal Military College of Canada, Kingston, Ontario B. Bakht JMBT Structures Research Inc., Toronto, Ontario L.G. Jaeger Halifax, Nova Scotia M. Braiter CSA, Mississauga, Ontario Chair Project Manager. November 2006 xlix

155 CAN/CSA-S6-06 French Translation Task Force G. Desgagné Ministère des transports du Québec, Québec, Québec L.M. Bélanger Ministère des transports du Québec, Québec, Québec D. Bernard Ministère des transports du Québec, Québec, Québec M. Blouin Ministère des transports du Québec, Québec, Québec J.P. Grenier Ministère des transports du Québec, Québec, Québec J. Labbé Ministère des transports du Québec, Québec, Québec Chair. M. Lacroix Ministère des transports du Québec, Québec, Québec J. Prévost Ministère des transports du Québec, Québec, Québec M. Savard Ministère des transports du Québec, Québec, Québec M. Vallières Ministère des transports du Québec, Québec, Québec M. Braiter CSA, Mississauga, Ontario Project Manager l November 2006

156 Canadian Highway Bridge Design Code Regulatory Authority Committee G. Richard Ministère des transports du Québec, Québec, Québec J. Francis Nova Scotia Department of Transportation and Public Works, Halifax, Nova Scotia T.B. Tharmabala Ontario Ministry of Transportation, St. Catharines, Ontario B. Bakht JMBT Structures Research Inc., Toronto, Ontario G.P. Carlin Les Ponts Jacques Cartier et Champlain Incorporée, Longueuil, Québec Chair Vice-Chair Vice-Chair Associate. C. Clarke Alberta Infrastructure and Transportation, Edmonton, Alberta D. Cogswell New Brunswick Department of Transportation, Fredericton, New Brunswick D.J. Evans Prince Edward Island Department of Transportation and Public Works, Charlottetown, Prince Edward Island A. Ikpong Yukon Department of Highways and Public Works, Whitehorse, Yukon D. Macleod Public Works and Government Services Canada, Gatineau, Québec R. Mathieson British Columbia Ministry of Transportation, Victoria, British Columbia D. Power Newfoundland and Labrador Department of Transportation and Works, St. John s, Newfoundland and Labrador R. Richardson Manitoba Department of Highways and Transportation, Winnipeg, Manitoba D.R. Sitland Government of Nunavut, Iqaluit, Nunavut T. Williams Government of the Northwest Territories, Yellowknife, Northwest Territories H. Yea Saskatchewan Highways and Transportation, Regina, Saskatchewan M. Braiter CSA, Mississauga, Ontario Project Manager November 2006 li

157 CAN/CSA-S6-06 Preface This is the tenth edition of CAN/CSA-S6, Canadian Highway Bridge Design Code. It supersedes the previous edition published in 2000, which amalgamated and superseded CAN/CSA-S6-88, Design of Highway Bridges, and the Ontario Ministry of Transportation s OHBDC-91-01, Ontario Highway Bridge Design Code, 3rd ed. Earlier editions of the CSA Standard were published in 1978, 1974, 1966, 1952, 1938, 1929, and Earlier editions of the Ontario Highway Bridge Design Code were published in 1983 and 1979 by the Ontario Ministry of Transportation. This Code uses the limit states design approach and reflects current design conditions across Canada as well as research activity since the publication of the previous edition. Several design aspects are addressed for the first time in this edition and a more detailed treatment of many areas is provided. This Code has been written to be applicable in all provinces and territories. As in the previous edition, there are 16 Sections in this Code. Section 1 ( General ) specifies general requirements and includes definitions and a reference publications clause applicable throughout this Code. It also specifies geometric requirements, based in part on the Transportation Association of Canada s Geometric Design Guide for Canadian Roads (1999), and hydraulic design requirements, based in part on the Transportation Association of Canada s Guide to Bridge Hydraulics, 2nd ed. (2001). There are also provisions covering durability, economics, environmental considerations, aesthetics, safety, maintenance, and maintenance inspection access. Section 2 ( Durability ) addresses durability aspects of materials used in the construction of highway bridges, culverts, and other structures located in transportation corridors. The durability requirements for all of the materials are based on common principles applicable to the deterioration mechanisms for each material, the environmental conditions to which the materials are subjected, and the protective measures and detailing requirements needed to limit deterioration to acceptable levels. Section 3 ( Loads ) specifies loading requirements for the design of new bridges, including requirements for permanent loads, live loads, and miscellaneous transitory and exceptional loads (but excluding seismic loads). The 625 kn truck load model and corresponding lane load model are specified as the minima for interprovincial transportation and are based on current Canadian legal loads. Ship collision provisions are also included in Section 3. Section 3 no longer specifies limits on the span lengths for application of the truck and lane loads. Accordingly, long-span requirements have been developed and appear in Section 3 and elsewhere in this Code (these requirements, however, should not be considered comprehensive). Section 3 covers long-span live loading and addresses wind tunnel testing for aerodynamic effects. Section 4 ( Seismic design ) specifies seismic design requirements for new bridges. These are based primarily on AASHTO (American Association of State Highway and Transportation Officials) LRFDEM-3-M, AASHTO LRFD Bridge Design Specifications, 3rd ed. (2005). Section 4 differs from AASHTO LRFDEM-3-M, however, by providing a more extensive treatment of the importance and response modification factors, new design and detailing requirements for structural steel ductile substructure elements, and design provisions for seismic base isolation. Section 4 also includes design provisions for the seismic evaluation of existing bridges and provisions pertaining to the seismic rehabilitation of existing bridges. Section 5 ( Methods of analysis ) specifies requirements for analyzing the basic superstructure of a bridge. In its methods for simplified analysis of bridge superstructures, a bridge is treated as a single beam and force effects are averaged over the width of the bridge and subsequently amplified to calculate the true intensity. Distribution factors are based on research conducted up to the late 1990s. Simplified elastic methods are included for the analysis of transverse effects. Refined methods of analysis for short-, medium-, and long-span bridges are also addressed. Section 6 ( Foundations ) is based, as in the previous edition, on the use of global resistance factors. Section 6 employs the limit states design approach, in which the term resistance is applied to the strength or capacity of the soil or rock at the ultimate limit state and the term reaction is associated with the serviceability limit state and is indicative of a particular deformation. Section 6 also emphasizes the importance of communication between the bridge structural engineer and the geotechnical engineer at all stages of a project.. lii November 2006

158 Canadian Highway Bridge Design Code Section 7 ( Buried structures ) deals with soil-metal structures with shallow corrugated plates in which thrust is the dominant force in the metal plates as well as soil-metal structures with deep corrugated plates and metal box structures in which flexural effects are also considered in the design of the metal plates. Provisions have been added for reinforced concrete precast and cast-in-place structures, including pipes, box sections, and segmental structures. Section 7 also specifies requirements for determining the properties and dimensions of the engineered soil and non-soil components and addresses construction supervision and construction procedures for soil components. Section 8 ( Concrete structures ) covers reinforced and partially and fully prestressed concrete components (including deck slabs) made of normal-density, semi-low-density, and high-density concrete of a strength varying from 30 to 80 MPa. Compression field theory is used for proportioning for shear and for torsion combined with flexure. The strut-and-tie approach is used for proportioning regions where the plane sections assumption is not applicable. Section 9 ( Wood structures ) specifies properties for materials and fastenings that are consistent with CAN/CSA-O86-01, Engineering Design in Wood, and includes data for structural composite lumber. Its provisions related to shear and compression, load distribution, design factors (in many cases), and laminated wood decks are essentially unchanged from those of the previous edition. The shear force concept has been reintroduced for the shear design of sawn wood members and the specified strength values in shear have been increased, in accordance with CAN/CSA-O In addition, the factors for load-sharing systems have changed. Section 10 ( Steel structures ) specifies the majority of this Code s design requirements for steel structures (with the exception of some seismic requirements specified in Section 4). Construction requirements that can have an impact on the resistance factors used in Section 10 are specified in Clause Because this Code has been expanded to include long-span bridges, cables and arches are now dealt with. In addition, durability is now addressed much more fully and clauses dealing with beams and girders, composite beams and girders, horizontally curved girders, orthotropic decks, fatigue, and construction have been revised. Section 11 ( Joints and bearings ) covers the deck joints and bearings most commonly used in Canada. Section 12 ( Barriers and highway accessory supports ) specifies crash test requirements for barriers and breakaway highway accessory supports. Crash testing may be waived for barrier and accessory support designs that have a successful in-service performance record. Performance levels alternative to those specified in Section 12 are permitted if approved by the regulatory authority. Section 13 ( Movable bridges ) specifies requirements for the design, construction, and operation of conventional movable bridges. Although the structural design aspects are based on the limit states design approach, the mechanical systems design aspects follow the working stress principle used in North American industry. Section 14 ( Evaluation ) includes new provisions concerning the three-level evaluation system, evaluation of deck slabs, and detailed evaluation from bridge testing. The provisions on the strength of wood members and the shear resistance of concrete have been improved. Another category of permit vehicle (Permit Annual or project [PA]) has been added. An optional probability-based mean load method that uses site-specific load and resistance information for more accurate evaluation is also provided. As in the previous edition, a more conventional approach to determining material grades from small samples is used in place of the Baye s theorem approach in CAN/CSA-S6-88. Section 15 ( Rehabilitation and repair ) specifies rehabilitation design requirements and provides guidance on the selection of loads and load factors for rehabilitation that is based on the intended use of the bridge following rehabilitation. Section 16 ( Fibre-reinforced structures ) specifies design requirements for a limited number of structural components containing either high- or low-modulus fibres. The high-modulus fibres (aramid, carbon, and glass) are employed in fibre-reinforced polymers (FRPs), which are used as replacements for steel bars and tendons. The low-modulus fibres are used for controlling cracks in concrete. Section 16 covers concrete beams and slabs, concrete deck slabs, and stressed wood decks. In this edition, Section 16 includes new design provisions that permit glass-fibre-reinforced polymer to be used as primary reinforcement and as tendons in concrete.. November 2006 liii

159 CAN/CSA-S6-06 Other new provisions in Section 16 permit the rehabilitation of concrete and timber structures using externally bonded FRP systems or near-surface-mounted reinforcement. The provisions concerning fibre-reinforced concrete deck slabs in the previous edition have been reorganized for this edition to include deck slabs of both cast-in-place and precast construction, which are now referred to as externally restrained deck slabs, whereas deck slabs containing internal FRP reinforcement are referred to as internally restrained deck slabs. The resistance factors of the previous edition have been revised and depend on conditions of use, with a further distinction made between factory- and field-produced FRPs. The previous edition s deformability requirements for FRP-reinforced and FRP-prestressed concrete beams and slabs are now dealt with in separate clauses that cover design for deformability, minimum flexural resistance, and crack control reinforcement. The effect of the sustained loads on the strength of FRPs is accounted for in this edition by limits on stresses in FRPs induced at the serviceability limit state. In addition, new stress limits for tendons have been introduced. The design for shear is now an adaptation of this Code s method for concrete structures and accounts for the decrease in shear carried by the concrete in FRP-reinforced beams. There are also modified provisions for barrier walls. Funding for developing and publishing this Code was provided by the governments of Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, the Northwest Territories, Nova Scotia, Nunavut, Ontario, Prince Edward Island, Québec, Saskatchewan, and Yukon, Public Works and Government Services Canada, and the Federal Bridge Corporation Limited. This Code could not have been developed without the cooperation of all of these sponsors. This Code was prepared by the Technical Committee on the Canadian Highway Bridge Design Code, under the jurisdiction of the Strategic Steering Committee on Structures (Design), and has been formally approved by the Technical Committee. It has been approved as a National Standard of Canada by the Standards Council of Canada.. November 2006 Notes: (1) Use of the singular does not exclude the plural (and vice versa) when the sense allows. (2) Although the intended primary application of this Code is stated in Clause 1.1.1, it is important to note that it remains the responsibility of the users of the Code to judge its suitability for their particular purpose. (3) This publication was developed by consensus, which is defined by CSA Policy governing standardization Code of good practice for standardization as substantial agreement. Consensus implies much more than a simple majority, but not necessarily unanimity. It is consistent with this definition that a member may be included in the Technical Committee list and yet not be in full agreement with all clauses of this publication. (4) CSA Codes and Standards are subject to periodic review, and suggestions for their improvement will be referred to the appropriate committee. (5) All enquiries regarding this Code, including requests for interpretation, should be addressed to Canadian Standards Association, 5060 Spectrum Way, Suite 100, Mississauga, Ontario, Canada L4W 5N6. Requests for interpretation should (a) define the problem, making reference to the specific clause, and, where appropriate, include an illustrative sketch; (b) provide an explanation of circumstances surrounding the actual field condition; and (c) be phrased where possible to permit a specific yes or no answer. Committee interpretations are processed in accordance with the CSA Directives and guidelines governing standardization and are published in CSA s periodical Info Update, which is available on the CSA Web site at liv November 2006

160 Canadian Highway Bridge Design Code Foreword In Canada, the legal mandate for establishing design and construction requirements for highways, including highway bridges, lies with the provincial and territorial governments. Before the publication of the previous edition of this Code, Ontario regulated the design and construction of highway bridges through the Ontario Highway Bridge Design Code. All of the other provinces and territories used CAN/CSA-S6, Design of Highway Bridges, with the exception of Manitoba, which adopted the bridge code published by the American Association of State Highway and Transportation Officials (AASHTO). The previous edition of the Canadian Highway Bridge Design Code was developed to provide a state-of-the-art model design code that could be adopted by all provinces and territories. This new edition is intended to serve the same purpose. Among the benefits associated with undertaking the development of this Code is the opportunity to establish safety and reliability levels for highway bridges that are consistent across all Canadian jurisdictions. Adoption of a single code makes it easier for the consulting and producer industries to respond to calls for proposals and eliminates the need for familiarity with the details of several codes. The adoption of a single code also supports the implementation of a national highway transportation system with agreed minimum standards and loadings for bridges on interprovincial highways, thereby encouraging consistency of vehicle weights across jurisdictions and supporting the objective of more cost-effective transportation of goods. Designers need to be aware, however, that although this Code establishes CL-625 loading as the minimum for bridges that are part of the national highway system, it is within the mandate of the provinces and territories to adopt a heavier or lighter live loading based on local traffic conditions. For example, Ontario requires (as specified in Annex A3.4) the use of a CL-625-ONT loading in the design of new bridges; this reflects the higher average regulatory and observed loads for trucks operating in the province. All of the requirements of this Code applicable to CL-W loading also apply to CL-625-ONT loading. Designers should always obtain approval from the regulatory authority when a live loading other than the CL-625 loading is to be used for design, and should check whether any variations from the requirements of this Code are in effect in the jurisdiction, e.g., for evaluation of existing bridges or issuance of overload permits. This Code was developed by taking into account the different regulatory structures and standards of Canada s provinces and territories. Overall priorities and objectives were established by the Regulatory Authority Committee (RAC), which also monitored the progress of the Code s development. In accordance with CSA procedural requirements, however, responsibility for the technical content of this Code was assigned to the Technical Committee (TC), as were decisions on how to deal with the priorities and objectives identified by the RAC. Because of the breadth and complexity of this Code, subcommittees (which were required to operate and report on a consensus basis) were established to oversee each section. In addition, task forces were established to handle specific aspects of this Code. The subcommittees and task forces reported to the TC through their Chairs. The extensive use of subcommittees permitted the recruitment of experts with the knowledge needed to address the sometimes highly specialized subjects covered by this Code. The developers of this Code wish to acknowledge the contributions of the following individuals, who were unable to complete their terms on the RAC and TC: Ismail Elkholy (RAC and former Vice-Chair of TC) (Manitoba Department of Highways and Transportation) and Peter Lester (RAC and TC) (Newfoundland and Labrador Department of Transportation and Works). This Code is complemented by CSA S6.1-06, Commentary on CAN/CSA-S6-06, Canadian Highway Bridge Design Code, which provides rationale statements and explanatory material for many of the clauses of this Code. Although this Code is being published in both English and French, CSA S6.1 is available only in English.. November 2006 lv

161 .

162 Canadian Highway Bridge Design Code Section 1 General 1.1 Scope Scope of Code Scope of this Section Terminology Reference publications Definitions General General administrative definitions General technical definitions Hydraulic definitions General requirements Approval Design Evaluation and rehabilitation of existing bridges Construction Geometry Planning Structure geometry Barriers Superstructure barriers Roadside substructure barriers Structure protection in waterways Structure protection at railways Auxiliary components Expansion joints and bearings Approach slabs Utilities on bridges Durability and maintenance Durability and protection Bridge deck drainage Maintenance Hydraulic design Design criteria Investigations Location and alignment Estimation of scour Protection against scour Backwater Soffit elevation Approach grade elevation Channel erosion control Stream stabilization works and realignment Culverts 31. November

163 CAN/CSA-S6-06 Section 1 General 1.1 Scope Scope of Code This Code applies to the design, evaluation, and structural rehabilitation design of fixed and movable highway bridges in Canada. There is no limit on span length, but this Code does not necessarily cover all aspects of design for every type of long-span bridge. This Code also covers the design of pedestrian bridges, retaining walls, barriers, and highway accessory supports of a structural nature, e.g., lighting poles and sign support structures. This Code is not intended to apply to public utility structures or to bridges used solely for railway or rail transit purposes. This Code also does not specify requirements related to coastal effects (e.g., exposure to sea action and icebergs) or to mountainous terrain effects (e.g., avalanches). For structures that can be subject to such effects, specialists need to be retained to review and advise on the design and to ensure that the applicable requirements of other codes are met. For bridges not entirely within the scope of this Code, the requirements of this Code apply only when appropriate. Necessary additional or alternative design criteria are subject to Approval Scope of this Section This Section specifies requirements for applying the Code and requirements of a general nature for bridges, culverts, and related works. These requirements govern basic geometry and hydraulic design. General requirements are also specified for subsidiary components, deck drainage, maintenance, and inspection access. Broad guidelines related to economic, aesthetic, and environmental considerations are also provided Terminology In CSA Standards, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; may is used to express an option or that which is permissible within the limits of the standard; and can is used to express possibility or capability. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application. 1.2 Reference publications This Code refers to the following publications, and where such reference is made, it shall be to the edition listed below, including all amendments published thereto. CSA (Canadian Standards Association) CAN/CSA-A /CAN/CSA-A Concrete materials and methods of concrete construction/methods of test and standard practices for concrete 2 November 2006

164 Canadian Highway Bridge Design Code CAN/CSA-A /CAN/CSA-A Precast concrete Materials and construction/qualification code for architectural and structural precast concrete products CAN/CSA-A257 Series-03 Standards for concrete pipe and manhole sections CAN/CSA-A Non-reinforced circular concrete culvert, storm drain, sewer pipe, and fittings CAN/CSA-A Reinforced circular concrete culvert, storm drain, sewer pipe, and fittings CAN/CSA-A Joints for circular concrete sewer and culvert pipe, manhole sections, and fittings using rubber gaskets B (R2002) Surface texture (roughness, waviness and lay). B97.3-M1982 (R2002) Tolerances and standard fits for mating parts, metric sizes B (R2003) Wire nails, spikes and staples C Canadian Electrical Code, Part I C22.2 No Motors and generators C22.2 No (R2001) Automatic transfer switches CAN/CSA-C22.3 No Overhead systems G4-00 Steel wire rope for general purpose and for mine hoisting and mine haulage G30.3-M1983 (withdrawn) Cold-drawn steel wire for concrete reinforcement G30.5-M1983 (withdrawn) Welded steel wire fabric for concrete reinforcement G30.14-M1983 (withdrawn) Deformed steel wire for concrete reinforcement G30.15-M1983 (withdrawn) Welded deformed steel wire fabric for concrete reinforcement CAN/CSA-G30.18-M92 (R2002) Billet-steel bars for concrete reinforcement November

165 CAN/CSA-S6-06 G /G General requirements for rolled or welded structural quality steel/structural quality steel CAN/CSA-G164-M92 (R2003) Hot dip galvanizing of irregularly shaped articles G (R2003) Sprayed metal coatings for atmospheric corrosion protection G279-M1982 (withdrawn) Steel for prestressed concrete tendons G Corrugated steel pipe products CAN3-O56-M79 (R2001) Round wood piles O80 Series-97 (R2002) Wood preservation. O Preservative treatment of piles by pressure processes O Preservative treatment of plywood by pressure processes CAN/CSA-O86-01 Engineering design in wood O Structural glued-laminated timber O Softwood lumber O Qualification code for manufacturers of structural glued-laminated timber S Commentary on CAN/CSA-S6-06, Canadian Highway Bridge Design Code CAN/CSA-S16-01 Limit states design of steel structures S157-05/S Strength design in aluminum/commentary on CSA S157-05, Strength design in aluminum S (R2003) Falsework for construction purposes CAN/CSA-S269.2-M87 (R2003) Access scaffolding for construction purposes 4 November 2006

166 Canadian Highway Bridge Design Code CAN/CSA-S Design and construction of building components with fibre-reinforced polymers W Certification of companies for fusion welding of steel CAN/CSA-W48-01 Filler materials and allied materials for metal arc welding W59-03 Welded steel construction (metal arc welding) W Certification of welding inspectors W186-M1990 (R2002) Welding of reinforcing bars in reinforced concrete construction AASHTO (American Association of State Highway and Transportation Officials) Guide Specifications for Bridge Railings (1989) (withdrawn). GVCB-1 (1991) Guide Specification and Commentary for Vessel Collision Design of Highway Bridges HB-17 (2002) Standard Specifications for Highway Bridges, 17th ed. ANSI/NEMA (American National Standards Institute/National Electrical Manufacturers Association) MG Motors and generators AREMA (American Railway Engineering and Maintenance of Way Association) Manual for Railway Engineering, 4th ed. (2005) ASCE (American Society of Civil Engineers) Standard Practice for Direct Design of Buried Precast Concrete Pipe Using Standard Installations (SIDD) ASME International (American Society of Mechanical Engineers) B1.10M-2004 Unified Miniature Screw Threads B (R2004) Preferred Limits and Fits for Cylindrical Parts B (R2003) Keys and Keyseats B Socket Cap, Shoulder, and Set Screws, Hex and Spline Keys (Inch Series) November

167 CAN/CSA-S6-06 ASTM International (American Society for Testing and Materials) A 27/A 27M-05 Standard Specification for Steel Castings, Carbon, for General Application A 36/A 36M-05 Standard Specification for Carbon Structural Steel A 48/A 48M-03 Standard Specification for Gray Iron Castings A 53/A 53M-04a Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless A e1 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished A 148/148M-05 Standard Specification for Steel Castings, High Strength, for Structural Purposes. A 153/A 153M-05 Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware A (2004) Standard Specification for Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and Strip A 240/A 240M-05 Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications A Standard Specification for Stainless Steel Bars and Shapes A Standard Specification for Carbon Steel Bolts and Studs, PSI Tensile Strength A b Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength A 325M-04b Standard Specification for Structural Bolts, Steel, Heat Treated 830 MPa Minimum Tensile Strength [Metric] A Standard Test Methods and Definitions for Mechanical Testing of Steel Products A b Standard Specification for Quenched and Tempered Steel Bolts and Studs A 486/A 486M-84 (withdrawn Standard) Specification for Steel Castings for Highway Bridges A a Standard Specification for Structural Bolts, Alloy Steel, Heat Treated, 150 ksi Minimum Tensile Strength 6 November 2006

168 Canadian Highway Bridge Design Code A 490M-04a Standard Specification for High-Strength Steel Bolts, Classes 10.9 and , for Structural Steel Joints [Metric] A Standard Specification for General Requirements for Wire Rods and Coarse Round Wire, Carbon Steel A a Standard Specification for Zinc-Coated Parallel and Helical Steel Wire Structural Strand A (R2003) Standard Specification for Zinc-Coated Steel Structural Wire Rope A 641/A 641M-03 Standard Specification for Zinc-Coated (Galvanized) Carbon Steel Wire A 653/A 653M-05 Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process. A 668/A 668M-04 Standard Specification for Steel Forgings, Carbon and Alloy, for General Industrial Use A 675/A 675M-03 e1 Standard Specification for Steel Bars, Carbon, Hot-Wrought, Special Quality, Mechanical Properties A 709/A 709M-05 Standard Specification for Carbon and High-Strength Low-Alloy Structural Steel Shapes, Plates, and Bars and Quenched-and-Tempered Alloy Structural Steel Plates for Bridges B Standard Specification for Bronze Castings for Bridges and Turntables B 36/B 36M-01 Standard Specification for Brass Plate, Sheet, Strip, and Rolled Bar B 121/B 121M-01 Standard Specification for Leaded Brass Plate, Sheet, Strip, and Rolled Bar B 746/B 746M-02 Standard Specification for Corrugated Aluminum Alloy Structural Plate for Field-Bolted Pipe, Pipe-Arches, and Arches C 506M-05 Standard Specification for Reinforced Concrete Arch Culvert, Storm Drain, and Sewer Pipe [Metric] C 507M-05 Standard Specification for Reinforced Concrete Elliptical Culvert, Storm Drain, and Sewer Pipe [Metric] C Standard Test Method for Determining Density of Structural Lightweight Concrete C Test Method for Obtaining Average Residual-Strength of Fiber-Reinforced Concrete November

169 CAN/CSA-S6-06 C e1 Standard Specification for Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers [Metric] D Standard Test Methods for Rubber Property Compression Set D a (2002) e1 Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers Tension D Standard Test Methods for Rubber Property Adhesion to Rigid Substrates D Standard Test Method for Rubber Deterioration in an Air Oven D ae1 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400 ft-lbf/ft 3 (600 kn-m/m 3 )). D Standard Test Method for Brittleness Temperature of Plastics and Elastomers by Impact D Standard Test Method for Rubber Deterioration-Surface Ozone Cracking in a Chamber D e1 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft 3 (2,700 kn-m/m 3 )) D Standard Specification for Polyethylene (PE) Plastic Pipe (SIDR-PR) Based on Controlled Inside Diameter D e1 Standard Test Method for Rubber Property Durometer Hardness D Standard Classification of Soils for Engineering Purposes (Unified Soil Classification System) D Standard Specification for Polyethylene Plastics Pipe and Fittings Materials D Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers D Standard Specification for Polytetrafluoroethylene (PTFE) Granular Molding and Ram Extrusion Materials D Standard Specification for Evaluation of Structural Composite Lumber Products F Standard Specification for Hardened Steel Washers 8 November 2006

170 Canadian Highway Bridge Design Code F 568M-04 Standard Specification for Carbon and Alloy Steel Externally Threaded Metric Fasteners PS (withdrawn Provisional Standard) Provisional Standard Specification for Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers AWPA (American Wood-Preservers Association) C33-03 Standard for Preservative Treatment of Structural Composite Lumber by Pressure Processes Government of Canada Navigable Waters Protection Act, RSC 1985, c. N-22 NCHRP (National Cooperative Highway Research Program) Report 230 (1980) Recommended Procedures for the Safety Performance Evaluation of Highway Appurtenances Report 350 (1993) Recommended Procedures for the Safety Performance Evaluation of Highway Features. NEMA (National Electrical Manufacturers Association) ICS (withdrawn Standard) Industrial Control and Systems: Power Circuit Accessories NLGA (National Lumber Grades Authority) Standard Grading Rules for Canadian Lumber (2003) NRCC (National Research Council Canada) National Building Code of Canada, 2005 National Fire Code of Canada, 2005 Research Council on Structural Connections Specification for Structural Joints Using ASTM A325 or A490 Bolts (2004) Transportation Association of Canada Geometric Design Guide for Canadian Roads (1999) Guide to Bridge Hydraulics, 2nd ed. (2001) Manual of Uniform Traffic Control Devices for Canada (1998) UL (Underwriters Laboratories Inc.) 845 (1995) Standard for Motor Control Centers U.S. Department of Defense MIL-S-8660C (1999) (cancelled Specification) Silicone Compound November

171 CAN/CSA-S Definitions General The definitions in Clauses to apply in this Code. Note: Additional definitions are found in Sections 2 to 16. In the case of a conflict between a definition in Sections 2 to 16 and a definition in Clauses to 1.3.4, the definition in Sections 2 to 16 takes precedence General administrative definitions Note: The general administrative terms defined in this Clause are capitalized wherever they are used in this Code in their defined sense. Approval or Approved approval, or approved, in writing by the Regulatory Authority. Checker a member or licensee of the Engineering Association who carries out the design check, rehabilitation design check, or evaluation check of a bridge or structure. Construction the construction, reconstruction, rehabilitation, repair, or demolition of a structure. Constructor (a) a Person that contracts to perform all of the Construction work on a project; (b) an Owner that contracts with two or more Persons for such Persons to perform part of the Construction work on a project; or (c) an Owner that performs all or part of the Construction work on a project.. Engineer a member or licensee of the Engineering Association who carries out the design, rehabilitation design, or evaluation of a bridge or structure. Engineering Association an organization authorized by charter to regulate the profession of engineering in a province or territory. Owner the Person having responsibility for and control of a bridge or structure. Person an individual, board, commission, partnership, or corporation (including a municipal corporation) and his, her, or its agents, successors, and assignees. Plans the drawings, documents, and specifications that define a Construction project, form part of the contract documents, or are included in the contract documents by reference; all Approved drawings and descriptions produced by a Constructor for the Construction of a bridge or other structure; and all revisions to the items described in this definition. Regulatory Authority the federal, provincial, or territorial Minister having governmental jurisdiction and control, his or her nominee, or the local authority to whom this authority is delegated General technical definitions Abutment a substructure that supports the end of a superstructure and retains some or all of the bridge approach fill. Arterial road an arterial road as defined in the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Auxiliary component a component of a structural system that does not constitute part of the intended load-sharing system. Auxiliary components include expansion joints, approach slabs, railings and barriers, and deck drains. Average annual daily traffic the total volume of traffic during a year divided by the number of days in the year. 10 November 2006

172 Canadian Highway Bridge Design Code Average daily traffic the total volume of traffic during a given time period, in whole days, greater than one day and less than one year, divided by the number of days in that time period. Average daily truck traffic the total volume of truck traffic during a given time period, in whole days, greater than one day and less than one year, divided by the number of days in that time period. Ballast wall that part of an abutment above the bearing seats used primarily to retain approach fill and to provide a support for an approach slab and expansion joint. Barrier a wall, railing, or fence that serves as a vehicular, pedestrian, bicycle, or combination barrier or as a noise or privacy barrier. Barrier wall a barrier that has no openings and is at least 800 mm high. Bearing a structural device that transmits loads while facilitating translation or rotation. Bevelled end a culvert end cut or formed to lie in a plane inclined to the vertical. Bicycle barrier a barrier for confining cyclists. Box culvert a closed-invert culvert with a monolithic rectangular or trapezoidal cross-section.. Bridge a structure that provides a roadway or walkway for the passage of vehicles, pedestrians, or cyclists across an obstruction, gap, or facility and is greater than 3 m in span. Clear recovery zone a roadside area that can be safely used by errant vehicles, is immediately adjacent to the edge of a traffic lane, and is clear of hazards. Coated reinforcement steel reinforcement that is used in concrete and is coated with a protective coating complying with the requirements of Section 8. Collapse a major change in the geometry of a structure rendering it unfit for use. Collector a collector road as defined in the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Combination barrier a barrier that serves as a vehicular barrier and as a pedestrian or bicycle barrier. Component a member of a structure requiring individual design consideration. Crossfall the transverse slope of a roadway, sidewalk, or deck surface. Crown Crown of a bridge or culvert the highest point on a curved soffit. Crown of a roadway the highest point of a cross-section, formed where opposite crossfalls meet. Culvert a structure that forms an opening through soil. Curb a raised surface beside a roadway, forming a vertical or nearly vertical face that delineates the roadway edge and in some cases also channels water. Cut-off wall a vertical wall attached to and extending below the end of a culvert or other structure. Deck a component of a bridge superstructure that carries and distributes wheel loads. Deck joint a structural discontinuity between two components, at least one of which is a deck component, that permits relative rotation or translation between the two. November

173 CAN/CSA-S6-06 Deck slab a solid concrete slab that carries and distributes loads to supporting members. Deck width the horizontal distance, measured at deck level perpendicular to the direction of travel, from face to face of sidewalks or curbs (or barrier walls if there are no curbs). Design the process of planning, analyzing, proportioning, drawing, and writing specifications for the Construction of a structure. Design lane a longitudinal strip that is a fraction of the deck width, within which a truck or lane load is placed for the purpose of design or evaluation. Design life a period of time, specified by an Owner, during which a structure is intended to remain in service. Divided highway a highway with two or more roadways separated by medians or barriers. Downpipe a pipe for conveying water from a deck drain to the ground or to a storm sewer. Downspout a short pipe extending from a deck drain to below the bridge superstructure. Drip groove a groove formed in a surface and intended to cause water to drop off the surface rather than run along it.. Ductility the ability to deform without failing after yielding. Evaluation the process of determining load-carrying capacity. Expressway an expressway as defined in the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Factored resistance the resistance of a component, connection, foundation, or cross-section calculated in accordance with the requirements and assumptions of this Code, including the application of appropriate resistance factors. Failure a state in which rupture, severe distortion or displacement, or loss of strength has occurred as a result of the load-carrying capacity of a component or connection having been exceeded. Falsework a temporary structure that is used to support another structure or a part thereof, usually during a particular Construction procedure or sequence. Fascia the surface that forms the lateral limit of a bridge. Fatigue the initiation or propagation of cracks caused by the repeated application of load. Fatigue limit state a limit state at which the effects of fatigue on the strength or condition of a structure are considered. Floor beam a transverse beam spanning between longitudinal girders, trusses, or arches. Freeway a freeway as defined in the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Gabion a wire mesh basket that is filled with stone or broken rock or concrete and forms part of a larger unit used for slope stability, erosion control, or related purposes. Girder a longitudinal beam resting directly on the substructure. Guiderail a rail system along the edge of a roadway to delineate the roadway edge and to help redirect errant vehicles. 12 November 2006

174 Canadian Highway Bridge Design Code Hazard any obstacle or other feature, e.g., an embankment, sideslope, or body of water deeper than 1 m, that, without protection, is likely to cause significant injury to the occupants of a vehicle striking it. Headwall a transverse wall at the end of a culvert. Highway a common and public thoroughfare, e.g., a road, street, avenue, parkway, driveway, square, place, bridge, culvert, viaduct, or trestle, designed and intended for, or used by the general public for, the passage of pedestrians, cyclists, animals, or vehicles. Highway class the class of highway determined in accordance with the volume of vehicular and truck traffic (see Clause ). Highway classification a category of highway, i.e., freeway, arterial road, collector road, or local road, that is used in establishing criteria for the geometric design of bridges. Interface shear shear at and in the plane of an interface between (a) dissimilar elements or materials, e.g., a deck slab and a beam, or a web and a flange; or (b) concrete cast at different times. Lane a traffic lane.. Limit states those conditions beyond which a structure or component ceases to meet the criteria for which it was designed. Load effect any effect on or response of a structural component due to loads, forces, imposed deformations, or volumetric changes. Load factor a factor applied to loads to take into account variability of loads, lack of precision in analysis for load effects, and reduced probability of loads from different sources acting simultaneously. Local road a local road as defined in the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Longitudinal the lengthwise direction. For bridges, this is normally the direction of traffic flow on the deck and of the main span. For culverts, it is normally the direction of the culvert axis. Long-span bridge a bridge with an individual span longer than 150 m. Median a raised or marked area that separates the roadways of a divided highway. Member an element or assembly of elements within a structure that performs an identifiable function and can require individual design consideration. Multiple-load-path structure a system of components in which the failure of any primary component or connection will not cause the structure to collapse. Open-type abutment an abutment in front of which is a slope extending downward from a point on the abutment face that is just below the superstructure. Orthotropic deck a deck that is orthogonally anisotropic. Normally this is a deck made of steel plate stiffened with open or closed steel ribs welded to the underside of the steel plate. Pedestrian barrier a barrier that is intended to confine pedestrians. Pedestrian bridge a bridge that provides a walkway primarily for the passage of pedestrians. Pier a substructure used to transfer superstructure loads from the spans it supports to the foundation. November

175 CAN/CSA-S6-06 Primary component a component of a structural system that performs an essential role in load transfer and, on becoming ineffective, will substantially reduce the load-carrying capacity of the system or cause the collapse of a single-load-path structure. Rehabilitation a modification, alteration, or improvement of the condition of a structure or bridge subsystem that is designed to correct deficiencies in order to achieve a particular design life and live load level. Reliability index or safety index a numerical measure of the reliability of structures or components. Resistance factor a factor applied to the unfactored resistance of a component or material at the ultimate limit state to take into account the variability of material properties and dimensions, quality of work, type of failure, and uncertainty in the prediction of the resistance. Return period the average period in years between the occurrence of an event (e.g., a flood) and the next occurrence of an event of the same type. Roadway that part of a highway that is intended for or can be used by vehicles, including traffic lanes, shoulders, and other adjacent areas such as those provided for clearance, pedestrians, or bicycles, if these areas are not separated by a barrier, by a guiderail, or by a curb that is at least 150 mm high.. Secondary component a component of a structural system that does not have an essential role in load transfer and whose removal from the structure would result in at most a minor redistribution of load effects to adjacent components. Serviceability limit state the limit state at which the effects of vibration, permanent deformation, and cracking on the usability or condition of a structure are considered. Sidewalk a pedestrian walkway located beside a roadway. Single-load-path structure a structure in which the failure of any primary component or connection will cause the structure to collapse. Skew angle the angle by which a bridge differs from a right-angled crossing. Normally, this is the angle between the longitudinal centreline of the bridge and a line perpendicular to the centreline of the bearings. Span the following distances: (a) the horizontal distance between the centrelines of adjacent piers or abutments; (b) where bearings are provided, the horizontal distance between bearing centrelines; (c) for rigid frames, including box culverts, the clear opening width; and (d) a distance specified as a span in another Section of this Code. Spread footing a footing that transfers structure loads directly to the underlying soil, rock, or engineered fill. Stress range the algebraic difference between the maximum and minimum stress at the fatigue limit state where tension and compression are of opposite sign. Stringer a longitudinal element supporting the deck and spanning between floor beams. Substructure that part of a bridge, including abutments and piers, that supports the superstructure. Superstructure that part of a bridge that spans water, a roadway, a railway, or another obstruction and is supported by the substructure. Temporary structure a structure with a design life of less than five years. Traffic barrier a barrier that is intended to confine vehicular traffic to a roadway or bridge deck. 14 November 2006

176 Canadian Highway Bridge Design Code Traffic lane a part of a roadway designated for the movement of a single file of vehicles. Transverse in a plane that is perpendicular to the longitudinal direction. Ultimate limit state a limit state that involves failure (including rupture, fracture, overturning, sliding, and other instability). Unfactored resistance the resistance of a component or connection based on specified material properties and nominal dimensions and calculated in accordance with this Code. Utilities transmission and distribution lines, pipes, cables, and other associated equipment used for public services including, but not limited to, electric power transmission and distribution, lighting, heating, gas, oil, water, sewage, cable television, telephone, and telegraph facilities. Vehicle a motor vehicle, motor-assisted bicycle, trailer, traction engine, car, truck, farm tractor, road-building machine, or any device drawn or propelled by power other than that of the driver or operator, but not including the cars or engines of electric, diesel, or steam railways. Yield strength the specified or established minimum yield strength of a material Hydraulic definitions Abnormal flood a flood or flood condition produced at a site by abnormal events or conditions downstream or upstream of the site, including ice jams. Apron an area of protective material laid on a stream bed to control local scour around a feature requiring protection. Backwater the rise in water level caused by a downstream obstruction or constriction in a channel. Bridge waterway that part of a bridge opening that is or can be occupied by water. Check flood a flood greater than the normal design flood, used to check that a waterway designed for the normal design flood will withstand a larger flood without embankment failure or structural collapse. Collar a concrete ring or stiffening component placed integrally with and at the end of a metal culvert. Competent velocity the velocity at which water will begin to move material of a given type and particle size. Degradation general and progressive lowering of the longitudinal profile of a channel by erosion. Depth of scour the depth of material removed from a stream bed by scour, measured below the original bed. Design flood a flood that a structure is designed to accommodate while conforming to specified requirements. Discharge the rate of flow of water in cubic metres per second. Drop structure a structure in a channel designed to lower the channel invert and the hydraulic grade line abruptly. Flood an event leading to an above-normal water level or discharge. Flood plain the relatively level area that adjoins a watercourse or other body of water and is subject to periodic flooding. November

177 CAN/CSA-S6-06 General scour scour in a stream bed that occurs at a structure as a result of general stream velocities exceeding the competent velocity of channel bed material. Improved inlet a culvert inlet incorporating refined inlet geometry for the purpose of improving the culvert hydraulic capacity. Inerodible durable enough to ensure that no important erosion will occur during the design life of the structure. Invert the lowest point at a particular section of a channel bed or culvert opening. Local scour scour in a stream bed adjacent to an obstruction, e.g., a pier or abutment, resulting from the disruption of flow caused by the obstruction. Normal design flood the design flood that a structure is required to accommodate without damage to the structure or approaches. Normal water level the average summer water level. Open-footing culvert a culvert with individual wall foundations on either side of a stream bed or passageway.. Original stream bed the bed as it existed or exists before an actual or planned modification or activity. Piping a movement of water through the soil around a structure that can cause loss of fine particles. Regulatory flood a designated flood primarily used to define the limits of a flood plain for regulatory purposes. In special circumstances, it may be specified as the design flood to be used for particular purposes. Relief flow the flood flow that bypasses the main structure opening at a stream or river crossing by flowing over the highway elsewhere or through a relief structure. Revetment a vertical or inclined facing of rip-rap or other material protecting a soil surface from erosion. Scour erosion of a stream bed by the action of flowing water. Stream bed the surface of a natural or modified channel bed. Ultimate bed elevation the anticipated lowest stream bed elevation occurring during the design life of a structure that allows for all scour and for degradation and artificial deepening. 1.4 General requirements Approval Approval shall be obtained for any item, component, process, analytical method, or method of construction that does not comply with this Code or is outside Code limits. Use of load or strength formulations from other codes in conjunction with this Code shall require an Approved investigation of compatibility and comparative safety levels, with appropriate adjustment of load and resistance factors. 16 November 2006

178 Canadian Highway Bridge Design Code Design Design philosophy In the interpretation and application of this Code, the primary concern shall be the safety of the public, including that of Construction and maintenance workers. Design shall be based on the consideration of limit states in which, at the ultimate limit state, the factored resistance is used to exceed the total factored load effect. Structural components shall be designed to comply with the ultimate limit state, serviceability limit state, and fatigue limit state requirements of the applicable clauses of this Code. The Engineer shall ensure that all limit states appropriate to the particular structure being designed are investigated. In accordance with Section 5, and unless otherwise specified, elastic methods of analysis shall be required for determining structural behaviour and for determining responses of a structure and its components at all limit states. Inelastic methods and experimental methods of analysis of bridges shall require Approval unless specifically required or permitted by this Code Highway class The highway class shall be determined in accordance with Table 1.1 for the average daily traffic and average daily truck traffic volumes for which the structure is designed. Unless otherwise Approved, all new bridges shall be designed to comply with Class A highway requirements.. Highway class Table 1.1 Highway classes (See Clause ) Average daily traffic (ADT) per lane (number of vehicles) A > 4000 > 1000 B > > C D < 100 < 50 Average daily truck traffic (ADTT) per lane (number of vehicles) Design life Unless otherwise Approved, the design life of new structures shall be 75 years Structural behaviour and articulation All joints and bearings shall be designed as part of a system of articulation with appropriate anchorages, guides, restraints, and freedoms. Where bridges have superstructures that are supported by bearings on piers or abutments or some combination thereof, relative movements between the superstructure and substructure shall be analyzed and shall be allowed for in the design. The possible effects of the inexact fit of components shall be considered, with normal Construction and fabrication tolerances assumed unless tolerances are specified on the Plans. The effects of deflection on the magnitude and position of bearing reactions shall be considered, with allowance for the approximate nature of deflection calculations. Where relative movements are restrained or limited, the resulting force effects and distortions shall be considered. November

179 CAN/CSA-S6-06 Unless otherwise Approved, superstructures with bearings and joints that electrically insulate them from the substructure and ground shall have direct ground connections to ensure that stray electrical and atmospheric electrostatic charges are harmlessly conducted to earth Single-load-path structures Special consideration shall be given to the critical components of single-load-path structures. Sufficient additional strength and protection shall be provided to ensure that they will not fail Economics After safety, the total projected lifetime cost shall be the determining consideration in selecting the type of structure, configuration of spans and supports, and Construction materials. This cost shall include allowances for inspection, maintenance, repair, and rehabilitation throughout the design life of the structure Environment Bridges, culverts, and their associated works shall be designed to comply with all environmental requirements established for the site. Wherever possible, features of archaeological, historical, and cultural importance shall be preserved. The design shall include an assessment of possible environmental effects and measures for limiting adverse effects to a practical minimum. Particular attention shall be paid to the preservation of wildlife and plant habitat. Structures on fish-bearing streams shall be designed to pass fish in accordance with Approved methods and criteria Aesthetics In the design and rehabilitation of structures, consideration shall be given to the appearance of the finished structure and to its compatibility with its surroundings. Wherever possible, the appearance of a structure shall be such that it will be generally perceived as an enhancement to its surroundings. Structures shall be simple and graceful in form, shall intrude minimally on desirable scenery, and shall exhibit an integrity in which the function of components is explicit in their form and their size realistically reflects necessary strength. Visual discontinuities or abrupt changes shall be avoided. Embellishments shall be permitted only where an important purpose is served and when the cost is demonstrably justified by the end served Evaluation and rehabilitation of existing bridges Evaluation Requirements for the evaluation and load testing of highway bridges are specified in Section 14. The requirements of all other Sections shall be applied as appropriate unless specifically modified by Section Rehabilitation design Provisions for the rehabilitation design of highway bridges are specified in Section 15. The requirements of all other Sections shall be applied as appropriate unless specifically modified by Section 14 or Construction General For the design of new bridges and the rehabilitation design of existing bridges, the appropriate Sections of this Code shall apply to the consideration of all stages of Construction. In the evaluation of strength and stability for all stages, the following shall be considered: (a) the intended sequence of Construction; (b) the absence of restraints that would be present in the completed structure; 18 November 2006

180 Canadian Highway Bridge Design Code (c) (d) (e) the possibility of loads or stresses in a member or component being temporarily greater than or of a reverse nature to those after completion; construction loads; and the consequences of failure Construction safety Protection for workers and the public at the construction site shall be in accordance with the applicable health and safety Acts and regulations. In the selection of construction methods and types of structures, the safety of construction workers shall be considered Construction methods When a bridge cannot be constructed without new or unusual procedures, or the assumed method of construction is not obvious, at least one method of construction shall be indicated on the Plans. When the method of Construction, rehabilitation, or demolition as envisaged by the Engineer is of such a nature as to cause critical load effects during Construction, the sequence of Construction stages and all necessary temporary support systems shall be shown on the Plans. The Plans shall indicate the location of all necessary temporary roadway and railway protection. The Plans shall require that when deviations from the indicated Construction methods are proposed, the Constructor shall submit new Plans to the Owner for Approval. The new Plans shall be signed and sealed in accordance with the requirements of the Regulatory Authority and indicate all proposed methods of Construction, sequences of Construction, and temporary support systems Temporary structures This Code shall apply to all temporary structures, except as follows: (a) CSA S269.1 and CAN/CSA-S269.2 shall apply to the design of falsework and temporary access scaffolding. (b) The requirements of the Regulatory Authority shall apply in lieu of this Code s requirements for durability and serviceability. (c) This Code shall not apply to temporary traffic barrier installations. Except where otherwise Approved, falsework and temporary access scaffolding plans shall be designed by an Engineer and independently checked Plans The Plans shall specify all necessary details of the bridge or structure, the material requirements, the classification of the highway, the design live load, the rehabilitation level (where applicable), and the year of publication and edition number of the edition of this Code used. The system of articulation shall be shown on the Plans, including the location and type of bearings. Jacking locations shall be shown as required by Clause Signing and sealing of drawings shall be performed in accordance with the requirements of the Regulatory Authority. The Plans shall include Approved specifications that are detailed and comprehensive enough to ensure that Construction is carried out in the manner and to the standards assumed in design and implicit in this Code. The requirements of this Code directly requiring the compliance of the Constructor shall be incorporated into the specifications Quality control and assurance Contractual requirements, Construction supervision, inspection, and testing shall be such as to ensure compliance with the Plans. November

181 CAN/CSA-S Geometry Planning The much greater cost and increased difficulty of widening bridges as compared to roadways shall be considered in determining whether the bridge cross-section should suit that of the proposed roadway or that planned for the roadway at some time in the future. Site conditions and requirements shall be considered in developing bridge alignment and plan geometry to accommodate existing and future traffic. The design average annual daily traffic, design hourly volume, and directional split shall be those forecast for a period starting not less than ten years after the design life start. For structures that are not easily widened, a longer period shall be determined from an economic assessment. Preference shall be given to straight horizontal alignments for bridges. The bridge deck longitudinal profile shall be continuous with the approach road profile Structure geometry General Roadway and sidewalk widths, curb widths and heights, and all other geometrical requirements not specified in this Code shall comply with the standards of the Regulatory Authority or, in their absence, with the Transportation Association of Canada s Geometric Design Guide for Canadian Roads. Sidewalks and bicycle paths shall be separated from traffic lanes by a barrier or guiderail, or by a curb with a face height of at least 150 mm and a face slope not flatter than 1 horizontal to 3 vertical. Sidewalks and bicycle paths not so separated shall be designed as part of the roadway Clearances Roadways and sidewalks Roadway and sidewalk clearances for structure openings and on structures shall comply with the standards of the Regulatory Authority or, in their absence, with the Transportation Association of Canada s Geometric Design Guide for Canadian Roads Railways Clearances for railways shall comply with the regulations of Transport Canada Waterways Clearances for navigable waterways shall comply with Clause Construction Clearances during Construction shall comply with the requirements of the agency with jurisdiction over the roadway, railway, or waterway passing through the opening. 1.6 Barriers Superstructure barriers The design of permanent barriers on structures shall comply with Section Roadside substructure barriers Vehicular barriers or guiderails shall be provided in compliance with applicable roadside design requirements when the horizontal clearance from the roadway edge to a structure component is less than 20 November 2006