Paper 27 - Detailed Design for Inland Waterways: the Opportunities of Real-Time Simulation

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1 Paper 27 - Detailed Design for Inland Waterways: the Opportunities of Real-Time Simulation ELOOT K.1'2; VERW ILLIGEN, J.1; VANTORRE, M.2 7Flanders Hydraulics Research, Antwerp, Belgium 2 Ghent University, Ghent, Belgium (1st author): katrien.eloot@ mow.vlaanderen.be ABSTRACT: The use of real-time simulations executed in a virtual inland waterway is increasing worldwide so that the accessibility of larger vessels in an existing waterway or chosen design vessels in a waterway to be constructed can be evaluated as close as possible to reality. The paper illustrates the opportunities of case by case decision through simulations for the Lys Diversion Canal connecting the river Seine in France with the river Scheldt in the Netherlands and Belgium by comparing the proposed values from design guidelines with the results of simulations. The design is based on possible meetings between a Vb push convoy at draft 1.8 m and a class IV motorship at 3.0 m. NOMENCLATURE ß Bow angle or course change in a bend (deg) B, b Beam of a vessel Bt Width of the navigation lane Cf Constant defining the relative position of the pivot point [-] h Water depth H Height of a vessel L, I Length of a vessel n Ratio of the wetted section of a canal to the midship section of the vessel (-) R Bend radius, inner for German guidelines T Draft of a vessel Tv Running draft of a vessel, draft plus sinkage UKC Underkeel clearance (m or % of T) W d Waterway width at bottom W t Waterway width at laden draft CEMT Conférence Européenne des Ministres des Transports FHR Flanders Hydraulics Research 1 INTRODUCTION Since the installation of the first full-mission ship manoeuvring simulator in 1988 and the Towing Tank for Manoeuvres in Shallow Water in 1992 (cooperation Flanders Hydraulics Research and Ghent University), the research on ship behaviour at FHR has focused on manoeuvring of sea-going vessels in shallow and confined water. As manoeuvring in confined water is the operational condition on most inland waterways and ports, a catch-up effort regarding inland navigation has been made by FHR over the last five years combining fundamental experimental research in the towing tank and applied simulation research at the inland simulator Lara. The paper illustrates the opportunities of realtime simulation by comparing the design guidelines for inland waterways with the results of detailed simulation design based on an accessibility study for class Vb push convoys. This study was carried out in 2012 to assess the upgrade of the Lys Diversion Canal which forms part of the Seine- Scheldt connection between France and Belgium (Figure 1, Table 1). Design proposals were set up by the responsible government agency for a twoway traffic lane on the canal allowing meetings and overtaking manoeuvres with a CEMT class Vb push barge convoy (185 m long, 11.4 m wide, 1.8 m draft - empty barges, Table 2) and a CEMT class IV motorship (85 m long, 9.5 m wide, 3 m draft). Due to several reasons (among others lack of available area and economic reasons), the commonly accepted waterway design guidelines used in different countries could not be met on each section of the canal. Therefore the proposed design with widened bends and adjusted canal sections was evaluated with real-time manoeuvring simulations on two coupled simulators (inland simulator Lara and simulator SIM225 from FHR). Several meetings SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 1/11

2 01% b e t Ä ^ Ä e class Vb and class IV vessels were simutatedunder different wind conditions, while only one overtaking manoeuvre was executed. Based on the track plots of the individual vessels an optimized design of the canal could be defined. Several projects have shown that the results of a concept design method for infrastructure on inland waterways, such as dimensions of bridge openings or a lock complex, is often too conservative and that there is scope for improvement in a detailed design phase through real-time simulation involving all parties in the design process. "SMART RIVERS 2013" As the realism of the ship behaviour will make or break the simulation results, the mathematical modelling of the manoeuvring behaviour is of utmost importance and at FHR mainly based on model tests. The knowledge on ship behaviour of inland vessels in their operational environment helps in defining realistic limits of the designed inland navigation channel and is disseminated by the Knowledge Centre Manoeuvring in Shallow and Confined Water ( e.g. through the participation in the PIANC Working Group 141 Design Guidelines for Inland Waterways. Rotterdam* London hr. lantwerp Ounkirfc [Ghent Brussels Cambrai Charleroi Rouen Compiègne (a) source (b) source bend m bend m bend 37 bend m bend m 966 m (c) Figure 1: (a) Location of the Seine-Scheldt connection (Seine from Le Havre - Paris to Scheldt from Ghent - Antwerp); (b) River Lys and Lys Diversion Canal on Belgian territory; (c) Bend sections of the Lys Diversion Canal with bend numbering and bend radius SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 2/11

3 Diversion Canal, bend radii R in m and (185 m) R/ L Nr. Bend R (m ) R/L (-) CO CO * 4.0 * design bend radius based on 4L 2 WATERWAY GUIDELINES 2.1 Introduction Waterway guidelines used in each specific country in Europe mainly work with a classification of the inland fleet based on the CEMT classes in Table 2. T able 2: C EM T 1992 classification of shi ps Class L (m ) B T H I II III IV Va Vb Via Vlb For the Lys Diversion Canal shown in Figure 1, which is at present (2013) accessible on the Flemish territory for inland ships up to class Va with draft limited to 2.8 m, the trajectory between bends 37 and 47 should be made accessible for class Vb push convoys in one way for each drafts up to 3.5 m and in two ways for meetings between a class Vb push convoy at 1.8 m draft and a class IV motorship at 3 m draft. This directive for the chosen fleet combination in two way traffic was decided by the responsible governmental agency Upper-Scheldt Division and specifically used in the real-time simulation study. Nevertheless the complete traffic of class I to class Vb vessels must be judged and more in detail the meetings of class Vb with lower classes on the canal under investigation. As a result meetings between a class Va vessel and Vb convoy, or between two Vb push convoys, can only take place at dedicated passing places. 2.2 Belgian guidelines In Belgium no directives for the design of a waterway for class Vb push convoys are available. In the Working Group 20 report of PIANC a summary is given of certain criteria established by the Flemish and Walloon authorities in a preliminary study for the modernization of the Upper-Scheldt (between the French border and the Ring Canal around Ghent, Table 3). Table 3: Criteria for the accessibility of class Vb push convoys on the Upper-Scheldt in WG20 report (PIANC) Draft Minimum width at 3.5 m draft Trapezoidal section Rectanqular section Minimum radius of curvature Minimum height under bridges 4.5 m 3.5 m 34 m with n < 5 42 m with n < m 6.5 m instead of 7 m so as to be able to keep existing bridges In Table 3 the maximum draft of the push convoy is 3.5 m, a value which is mainly used as maximum draft for all waterways to be upgraded for class Vb convoys in Flanders, with an underkeel clearance of 1 m (or 29% of the maximum draft). In reality, for both section types (trapezoidal - slope angle not specified - or rectangular) the ratio n of the canal section to the ship's section can be smaller than 4.75 to 5 (e.g. the present profile of the straight section between bend 45 and 46 yields a ratio n of 4.29 for a class Vb convoy). 2.3 Dutch guidelines (Waterway Guidelines, 2011) According to the Dutch guidelines the design process for commercial navigation starts with the definition of the desired CEMT class of the reference vessel which is the largest vessel that can smoothly and safely navigate the waterway under investigation, being class Vb for the Lys Diversion Canal in Figure Waterway profile s The three types of profile of a waterway for commercial navigation are: Normal profile for two-lane traffic; Narrow profile for two-lane traffic; SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 3/11

4 profile. The chosen profile type depends on the traffic volume to be expected on the waterway under investigation. The maximum traffic volume is based on the total number of vessels per year and is not specified according to the classes so that in the case study of the Lys Diversion Canal in Figure 1 different profiles could be used for a one way or single-lane profile for a class Vb push convoy at all drafts and a two-way normal or narrow profile for meeting classes of Vb and IV with 1.8 and 3 m draft, respectively. All specifications in the guidelines are based on one reference vessel, class Vb in Table 2. As it is expected that the traffic management could be organised so that meetings of class Va and Vb vessels can be planned at dedicated passing places and the number of class Vb push convoys on the canal will only be a minor fraction of the number of ships sailing on the canal nowadays, a narrow profile for (two) class Vb (or even lower as meetings will only take place with class IV) could be calculated as design for two-lane traffic Straight sections o f waterway Water depth: according to the Dutch guidelines, the water depth to draft ratio h/t should be 1.4 for a normal and 1.3 for a narrow and singlelane profile. With 1 m UKC the h/t ratio is 1.29 for a laden Vb push convoy (draft 3.5 m). For low speed manoeuvring the sinkage and trim, or thus squat, is expected to be small so that the UKC is sufficient. Table 4: Waterway width at two levels in relation to the beam of the reference vessel B and with absolute values Class Vb Class IV Profile wd Wt wd Wt wd Wt Normal 2B 4B Narrow 2B 3B Single-lane B 2B Waterway width: the waterway width for commercial navigation is specified at three levels: o the minimum waterway depth required (Wd) on the waterway bottom; o in the keel plane of a laden vessel (Wt); o in the keel plane of an unladen vessel, in connection with the extra width that an unladen vessel may need in the event of side winds. For a class Vb push convoy the width W d and W t of the straight sections should therefore be as shown in Table 4. The side wind increment for inland zones for the different classes and profiles is shown in Table 5. Selecting a narrow profile for meetings on the Lys Diversion Canal the minimum width at the laden draft W t corresponds to the value in Table 3 for the criteria on the Upper-Scheldt. The side wind increment is nevertheless not specified in Table 3 so that a total width of 46.2 m (34.2 m + 12 m) should be available on a straight narrow two-lane section at the unladen draft of e.g. 1.8 m below the waterline for meetings of two push convoys Vb. Combining the values for the narrow profile of class Vb en class IV with wind increment (by adding and dividing by 2) a value of 40.9 m is found while for the sum of a single lane for a class Vb and for a class IV a value of 41.8 m is calculated for W t (without wind increment at laden draft). Table 5: Side wind increment Aw Class Vb Class IV Profile A» A Normal 9 5 Narrow 12 7 Single-lane to be determined to be determined Bends The minimum bend radius for a normal profile is 6L (with L the overall length of the vessel) and for a narrow profile 4L. Due to drifting while turning a width increment must be taken into account which depends on the bend radius and the loading condition of the vessel. If the course change in the bend or thus the bow angle ß is larger than 30 degrees, a width increment (at the inside of the bend) of ABi and ABi +AB2 in the keel plane of respectively the laden vessel and empty vessel is necessary. When the bow angle ß < 30, the width increment may be multiplied by a factor ß/30. Table 6: Bend width increment AB for a narrow profile (bend radius 4L or 740 m ) Class Vb Class IV Laden A Bi Em pty A B The bend radii are larger than 6L for bend numbers 37, 40, 43 and 44 (Table 1) for the Lys SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 4/11

5 ja US«?? D î ^ ^ i^ ^ a n a l and in between 4 and 6L for bends 38, 8 r4 5 )46 and 47. Selecting a narrow profile for meetings in a bend, in correspondence with the straight sections, the width increments for class Vb and IV vessels are shown in Table 6. They are calculated with the equation AB = C L2/R with C values depending on the CEMT class and the loading condition. Combining the width of a straight section without wind increment (no wind increment for laden condition) of 34.2 m with the bend width for meetings of two laden class Vb push convoys in a bend with 4L radius, the waterway width in the keel plane of the laden vessels should be 52.8 m. When a class Vb push convoy (empty or draft 1.8 m) meets a class IV vessel (laden or draft 3.0 m) the bend width increments of the two vessel types could be summed with a required width (straight section with wind increment 40.9 m plus bend width increment 20.9 m) of 61.8 m in the keel plane of the empty push convoy. Using these results for the three consecutive bends on the Lys Diversion Canal with the smallest bend radii, more specifically bends 45, 46 and 47, the bend width is shown in Table 7 and could be reduced to a lower width for bend 46 and 47 thanks to the smaller bow angle. Table 7: Bend width in the keel plane of the empty push convoy for bends 45 to 47 based on a Nr. Bend ß (deg) ß/30 (-) (limited to 1) Bend w idth Summary Dutch guidelines Although the Dutch guidelines are meant for the design of a waterway for one design ship (e.g. class Vb), the guidelines for the determination of the width of a straight section and of a bend are used for a combination of an empty class Vb push convoy at draft 1.8 m and a laden class IV motorship at a draft of 3 m. Considering a narrow profile the width of a straight section should be 40.9 m in the keel plane of the empty vessel (e.g. at a draft of 1.8 m) while the width of a bend in the same plane depends on the bend radius, the bow angle and the loading condition and varies between 52.3 m for bend 47 and 61.8 m for bend 45 on the Lys Diversion Canal. "SMART RIVERS 2013" 2.4 French guidelines (Circular No , 1976) The French guidelines discussed in this paper are valid for a canal with negligible current velocity Waterway p rofile s and classes Two types of waterway profiles for two-lane traffic are considered in the French circular related to the characteristics of inland waterways: a normal profile with a minimum ratio n of 6; a reduced profile with a minimum ratio n of 5. The waterways are subdivided in 8 classes from class 0 to class VII of which class V and VI are related to CEMT class Vb push convoys with respectively a draft of 2.5 m (1500 to 3000 tons) and 3.0 m (3000 to 5000 tons) Straight sections and bends In the French guidelines a (minimal) navigational rectangle is defined which must match within the wetted section of the waterway. Bank slopes are generally 2/1 or 3/1 (horizontal/vertical distance notation in French guidelines). The characteristics of a class V and VI waterway (CW) according to the French guidelines is summarized in Table 8 for the navigational rectangle (Nav. Rect.) and for a normal (NP slope 2/1 or 3/1) and reduced profile (RP slope 2/1 or vertical). For a CEMT class IV vessel a waterway class IV should be selected that corresponds completely to the classes V or VI depending only on the selected draft of 2.5 or 3.0 m. Table 8: Navigational rectangle and normal and reduced profile sections for different slopes and for CW Nav. Rect. NP 2/1 NP 3/1 Width Bottom width Bottom width V VI CW Bottom width RP 2/1 RP vertical Bottom width V VI A minimum underkeel clearance of 1 m is selected for the navigational rectangle. For a SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 5/11

6 nevertheless the water depth is increased with 0.3 to 0.5 m so that taking into account the maximum draft of 3.0 m for a class VI waterway a larger UKC is taken compared to the value of 30% used in the Dutch guidelines for a narrow profile. The bottom width is larger than the 2B bottom width for a narrow profile and equals approximately the 3B bottom width for a normal profile in the Dutch guidelines. Using these results for meetings of a CEMT class Vb push convoy at a draft of 1.8 m and a CEMT class IV motorship at a draft of 3.0 m a trapezoidal cross section could be considered with a bottom width of 32 to 34 m and a width in the keel plane of the empty push convoy of 50.2 m for a normal profile at slope 3/1 and 42.0 m for a reduced profile at slope 2/1. This value of 42.0 m corresponds to the width in the keel plane of the empty push convoy according to the Dutch guidelines (40.9 m) where a width increment due to wind was considered. The bend radii for class V and VI waterways are 1000 m or 5.4L (with L 185 m) for a normal profile and 750 m or 4.1 L for a reduced profile. For a class IV waterway with a vessel length of 105 m these values are 7.6L and 4.8L, respectively. For a reduced profile the minimal bend radius equals thus the recommended radius in the Dutch guidelines. The bend width increment only depends on the bend radius R and is for a class V and VI waterway 16,000/R or thus 21.3 m for a reduced profile bend radius of 750 m. Although the bend width is increased at the inside of the bend in the Dutch guidelines, in the French guidelines this increment is proposed to be executed at the outside. As the bend radius differs for bends 45 to 47 Table 9 gives the bend width in the keel plane of the empty push convoy at draft 1.8 m for a reduced profile. As no reduction factor, based on the course change to be executed in the bend, is available in the French guidelines the difference in bend width for bends 45, 46 and 47 is negligible (Table 9) and corresponds approximately with the highest value of 61.8 m for bend 45 according to the Dutch guidelines. Table 9: Bend width in the keel plane of the empty push convoy for bends 45 to 47 based on the French guidelines for a reduced profile Nr. Bend Bend radius Bend w idth 45/ German guidelines (Guidelines 2011 edition) The German guidelines for standard cross sections of inland navigation channels are especially related to push convoys of 185 m of length and large motorships of 110 to 135 m with both a beam of m and a draft of 2.8 m Waterway profile s The German guidelines define four different standard waterway profiles for two-way or one-way traffic depending on the design of the banks: trapezoidal profile (T-profile) - sloped banks on both sides of the canal; rectangular profile (R-profile) - vertical banks on both sides of the canal; rectangular trapezoidal profile (RT-profile) - sloped bank on one side of the canal, vertical on the other side; combined rectangular trapezoidal profile (KRT-profile) - banks are vertical below water level and sloped in the water-level fluctuation zone and above; and are thus more detailed than the Dutch and French guidelines. An additional remark is also made for combinations of inland vessels which dimensions differ from the design vessels (e.g. in the case of the Lys Diversion Canal, two-way traffic for a push convoy and a class IV vessel). The width of the navigation lane can then be increased or reduced in proportion to the relation of the sum of the beams of the new vessels to the design vessels in the guidelines Straight sections o f waterway The width of the waterway at different heights depends on the profile so that two profiles can be selected for the Lys Diversion Canal with a T-profile in straight sections and a RT-profile in the bends and in the straight section between bends 46 and 47. The German guidelines suppose a design draft of 2.8 m and a water depth to draft ratio of 1.4 or thus a water depth of 4.0 m. For larger drafts, e.g. the 3.0 m draft of the class IV vessel, the water depth should be increased to meet the 1.4 h/t ratio or thus 4.2 m. The same sinkage of 0.35 m is supposed for the calculation of the running draft Tv. Although the design for the Lys Diversion Canal is based on meetings between two different CEMT classes with different draft, the designed straight sections are for both navigation lanes considered with the maximum meeting draft of 3.0 m. For a T-profile waterway (Figure 2), open for meetings of a class Vb push convoy and a class IV motorship, the navigation lane width differs with SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 6/11

7 1 k5 m for tkc push convoy and 13.0 m for the class IV v^sser For the other widths (distance between the individual navigation lanes, distances to the banks) no distinction is made based on the vessel dimensions so that the bottom width for 3/1 (=1:3 in Figure 2) sloped banks is 28.4 m (2.5B with B m) while at the unladen draft of 1.8 m of the push convoy the waterway width is 42.9 m. This value is respectively 2 and 0.9 m more than the width in the keel plane of the empty push convoy according to the Dutch and the French guidelines for a reduced profile. Between bends 46 and 47 a RT-profile is used for the straight section (Figure 3). The individual manoeuvring lanes are 0.5 m wider compared to the T-profile and the bank width at the rectangular bank is reduced to 4.0 m compared to the width of 11.6 m at the waterline for the 3/1 sloped bank. The bottom width of 34.5 m is larger than for the T-profile while the width at the unladen draft of 1.8 m of the push convoy is 41.7 m. S u = 11.6m B = 30.5m S u = 11.6m = 1.5m = 2.0m = 1.5m hi = 5.25m Bí = 15.5m Bí = 13.0m dynz BWu T W f = 0.7m h = 4.2m Tv = 3.35m T = 3.0m Wd = 28.4m B f = 33.5m Bw = 53.6m Figure 2: T-profile for a straight section based on the German guidelines and meetings for an empty class Vb push convoy and a laden class IV motorship Su = 4.pm B = 31.5m S u = 11.6m = 2.0m = 1.5m hi = 5.25m Bí = 16.0m Bí = 13.5m dynz BWu # W f = 0.7m h = 4.2m Tv = 3.35m T = 3.0m Wd = 34.5m Bp = 37.0m Bw = 47.1m Figure 3: RT-profile for a straight section based on the German guidelines and meetings for an empty class Vb push convoy and a laden class IV motorship Table 10: Increased bend width for class Vb and IV for the Lys Diversion Canai Bend w idth B1 Class Class Nr. Bend R Vb IV / Bends The required waterway width in bends (one-way traffic or navigation lane) is: B1 = J(R + b)2 + (Cf. I)2 R b + minb1 In Table 10 the increased bend width B^ for a class Vb and a class IV vessel are presented for the different bends of the Lys Diversion Canal. Due to the large length of the push convoy the navigation lane width doubles for the bends 45 to 47 with the smallest bend radius. The new values for the bends considered during the simulations (Table 11) can be obtained by increasing the widths in the RT-profile in section with 18.2 m plus 3.9 m for bend 45 and 47 and (1) SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 7/11

8 wm? w ito '16.9 m/plus 3.6 m for bend 46 (class Vb, values for B^IWfri Table 10 minus 16.0 m, class IV values for Bt from Table 10 minus 13.5 m). Table 11: Bend width in the keel plane of the empty push convoy for bends 45 to 47 based on the Nr. Bend Bend radius Bend w idth 45/ PIANC In the Working Group 20 PIANC guidelines a distinction is made for class Vb waterways depending on a heavy or low traffic condition, with the possibility of reducing the navigation channel sections in case of low traffic operating at lower speeds. For speeds below 10 km/h a waterway depth of 4.5 m (for a maximum draft of 3.5 m) with a reduced width at the water surface of 45 m (4 x 11.4 m = 45.6 m) is proposed. A summary of the parameters according to PIANC is given in Table 12. A maximum authorized speed is related to bank protection and can be imposed by waterway management authorities. Table 12: Proposed parameters for Class Vb (185 m Characteristics High traffic density Low traffic density Ratio n > 10 > 7 Channel depth 5.6 m 4.5 m Draft 4 m 3.5 m h/t Minimum radius of curvature 6L 4L Extra width on bends0 Graewe's formula* Graewe's formula Extra width preferably on the inside o f a bend. * Graewe's formula is used in the Netherlands, see Dutch guidelines. 2.7 Summary o f guidelines Although the guidelines differ from country to country, they give the possibility to calculate the width of a straight section and the minimum bend radius and the (additional) bend width. If two-way traffic is considered, only the German guidelines give the possibility to consider two different CEMT classes for the meetings. For the other guidelines only one design ship is taken and only a free interpretation of the guidelines gives the possibility "SMART RIVERS 2013" to reduce the required width for meetings of two different classes. For all guidelines the width in the keel plane of the empty push convoy for two-way traffic of a push convoy and a class IV motorship can be considered to be around 42 m for a reduced profile. In the previous chapters the bend width was calculated in the keel plane of the empty push convoy for bends 45 to 47 of the Lys Diversion Canal mainly based on the guidelines for a reduced profile as the traffic density of Vb push convoys is expected to be low. Table 13 gives a comparison of the values based on the Dutch, French and German guidelines. Table 13: Comparison of the bend width in the keel plane of the empty push convoy for bends 45 to 47 Nr. Bend Bend w idth Dutch French German Although the (bend) width at the laden and ballast draft are most important, there is also an important difference in bottom width according to the different guidelines with the smallest width of 2B or 22.8 m for the Dutch guidelines and the largest width of 34.5 m without or 56.6 m with bend width increment for the German guidelines in a RT-profile. 3 CASE BY CASE DECISION THROUGH SIMULATION STUDY To be able to optimize the modifications to be made to the Lys Diversion Canal for the accessibility of class Vb push convoys a simulator study was executed for the consecutive bends 45, 46 and 47 with smallest bend radii compared to the other bends on Figure Description o f the waterway configuration The description of the waterway configuration is subdivided in straight sections and bends. The straight section between bends 45 and 46 is the typical profile for the existing Lys Diversion Canal accessible for class Va motorships (Figure 4). The design bottom width is 25.5 m (or 2.2B) - although the actual bottom width can be larger up to 32 m - and the waterline width is 50.5 m. With a slope of 3/1 (or 12/4) the width in the keel plane of the empty push convoy is almost 40 m which is SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 8/11

9 the width of 42 m suggested by the guidëftneft The bottom width lies in between the values from the Dutch (lowest value 2B for a narrow profile) and the French (highest value 2.8B) guidelines. Due to the restricted waterway length between bends 46 and 47 (500 m or 2.7L) the straight straight section between bend 45 & 46 section is realized as a RT-profile and gives thus a wider width in the keel plane of the empty push convoy compared to the proposed value from the guidelines. +5m61 TAW (waterline) +1m11 TAW (bottom) distance in meter 1000 m straight section bend 45 bend 46 bend bend 45 & 47 bend 46 Figure 4: Longitudinal and cross sections for bends 45, 46 and 47 and the straight section between 45 and 46 as actual profile of the Lys Diversion Canal All bends in Figure 4 are widened at the inner side and have a RT-profile with a rectangular profile at the inner side. Bend 46 has a natural wide profile with a bottom width of 54.6 m and a waterline width of 65.8 m giving a width in the keel plane of the empty push convoy of 60.4 m. This width is larger than the design value according to the Dutch guidelines but smaller than the values from the other countries (Table 13). Bends 45 and 47 are comparable with a bottom width of 42.3 m and a waterline width of 53.5 m. The width at the keel plane of the empty push convoy is 48.1 m and is smaller than all proposed values from the guidelines (Table 13). The bottom width nevertheless lies in between the values from the Dutch (lower value) and the German and French guidelines (higher value). The simulation study focused on meetings between a class Vb (with draft 2.4 m instead of 1.8 m due to the availability in the simulator database) and a class IV vessel (with draft 2.5 or 3.0 m) in the bends and in the straight sections between the bends. As bridges are present at both sides of bend 45 and downwards bend 47 the passage of these bridges can influence the meeting between the vessels. Figure 5: Simulation run SS_AKL_V2_002 on the inland simulator Lara SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 9/11

10 study The Simulation study was executed with two coupled full mission (inland) simulators Lara and SIM225. While a skipper was sailing on a class Vb push convoy at Lara (Figure 5), another skipper was preparing the meeting with this push convoy while handling a class IV vessel seen as an approaching vessel on Figure 5. The evaluation of meetings in straight sections showed that careful meetings (and even one overtaking manoeuvre) could be executed in the straight section between bend 46 and 47 thanks to the wide RT-profile of this section designed by the responsible government agency taking into account the restricted length of the straight section of 500 m or thus 2.7L (Figure 6). The straight section between bends 45 and 46 is less favourable for executing meetings as the successive bends 46 and 45, with a short straight section in between, require a zigzag manoeuvre which is hindered by the bridge passage at the southern end. The evaluation of meetings in bends give comparable positive evaluations from both skippers executing the meetings in bend 45 or 46 although their design is strongly different. The bend radius and width of bend 45 is small compared to the design guidelines but the chosen RT-profile helps the skipper, sailing in the inner side of the bend, to position the ship with the bow as close as possible to the rectangular bank (Figure 7). The speed of both meeting vessels in bend 45 must be controlled to a value of 5 to 6 km/h. The proximity of the bridge north of bend 47 and the crossing with the northern waterway together with the smaller T-profile of the canal upwards the bridge are the main difficulties of meetings executed at bend Conclusion o f case by case decision Concluding the results of the real-time simulations with coupled simulators the overall layout of the canal with straight sections, bends, different cross section profiles and availability of bridges determine the accessibility of a waterway for a specific design ship and/or specific traffic and thus meetings. Although the design of the bends and straight sections was not necessarily in accordance with the design guidelines of Dutch, French and German authorities, based on the execution of real-time simulations with a realistic behaviour of both meeting vessels (due to the use of coupled simulators) it could be concluded that the design of the canal between bends 45 and 47 only had to be adjusted within the spatial constraints of these bends (with width values smaller than the proposed design values). The favorable meeting places are at bend 46 and the straight sections in between bends 46 and 47. Thanks to the decision to further widen the inner side of bend 45 compared to the design during the simulation study, bend 45 can be used for meetings in a controlled way at low speed. meeting between class Vb at draft 2.4 m and class IV at draft 2.5 m bottomline at draft 2.4 m m TAW waterline m TAW bottom Figure 6: Track plots of class Vb (black) and class IV (orange) vessels during the meeting in between bends 46 and 47 during simulation SS_AKL_V2_002 SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 10/11

11 bottomline at draft 3.0 m m TAW waterline m TAW bottom meeting between class Vb at draft 2.4 m and class IV at draft 3.0 m Fiqure 7: Track plots of class Vb (black) and class IV (oranqe) vessels durinq the meetinq in bend 45 durinq simulation SS AKL V CONCLUSION The opportunities of real-time simulations executed as realistic as possible as in real life are worldwide accepted in the design of existing waterways or waterways under construction. Real-time simulations are widely used at Flanders Hydraulics Research for the evaluation of the accessibility of inland waterways thanks to the installation of the inland simulator Lara. A full adaptation of an existing Belgian waterway to the proposed widths of European national guidelines is due to economic and spatial constraints rather an exception than the rule. In this paper the results of a simulation study for the Lys Diversion Canal, being a part of the connection between the river Seine in France and the river Scheldt on Dutch and Belgian territories, have been compared with the proposed design from national (Dutch, German and French) guidelines. Although this could be seen as reverse engineering, the comparison is made to judge the opportunities of case by case decisions based on real-time simulations. It can be concluded that the level of ease of the meetings although designed based on a narrow profile give - for example for bend 46 - a good level of ease (reserve during the manoeuvre and design close to the guidelines) while the level of ease is restricted and just acceptable for bend 45 with a design more restricted than proposed by the guidelines. Based on these simulation results and the additional spatial and economic constraints the responsible government agency could evaluate the design and consider additional small adaptations to the waterway. ACKNOWLEDGEMENTS Flanders Hydraulics Research wants to acknowledge the Upper-Scheldt division from Waterwegen en Zeekanaal NV and the responsible project engineer Dr. Griet De Backer ( for the opportunity to execute real-time simulations with coupled simulators in the design process for the upgrade of the Lys Diversion Canal. REFERENCES Working Group n 20 of PIANC, Factors Involved in Standardising the Dimensions of Class Vb Inland Waterways (Canals) Rijkswaterstaat, Ministerie van Infrastructuur en Milieu, Waterway Guidelines 2011, the Netherlands Ministry of Infrastructure and Secretariat of State for Transport, Circular No o f 1st March 1976 relating to the characteristics o f inland waterways, France Federal Ministry of Transport, Building and Urban Development, Guidelines on standard crosssections o f inland navigation canals, 2011 edition, Germany SM ART RIVERS 2013 (w w w.sm artr ivers2013.org ) Paper 27 - Page 11/11