Hollow-core Building System Design Manual

Transcription

1 C O L O R A D O G E O R G I A Hollow-core Building System Design Manual O R E G O N U T A H W A S H I N G T O N Providing Engineered Concrete Solutions

2 2 Copyright 2015 By EnCon Design, LLC HCM

3 Introduction This EnCon Hollow-core Building System Design Manual has been designed to illustrate the many ways in which hollow-core precast concrete can function as a multipurpose building system or as an integral component of a building system. Owners, contractors, architects, and engineers will discover that hollow-core building systems can be used in a wide variety of settings and offer a myriad of benefits. Hollow-core systems are cost effective, allow construction to remain on budget and on schedule, require less maintenance, and create less environmental impact than conventional building materials. Strawberry Park Residential applications include single family and multifamily dwellings, the hospitality industry, and specialized housing, such as dormitories, assisted-living and nursing homes. Be it low-, mid-, or high-rise construction, a hollow-core structure is fire resistant, moisture resistant, allows less sound transmission, offers flexible floor plans, and meets unique building needs and challenges. Hollowcore precast concrete helps manage heating and cooling demands, resulting in reduced energy costs. The safety, security, and high fire resistance it offers keep insurance rates low as well. Structurally, a hollow-core building system provides high load capacity for floors, open clear spans, high vibration resistance, finished ceilings and floors, reduced floor-to-floor height, and natural space for electrical conduit, plumbing, and HVAC ductwork. This manual includes sections addressing Frequently Asked Questions and technical data, as well as product cross section details and connection concepts. Also enclosed are sample specifications and a set of typical general notes. Chateau Lodge at Beaver Creek Radisson Hotel No matter what the type of design, EnCon s hollow-core precast concrete building systems provide homeowners, designers, and contractors with benefits that are unsurpassed. For further information or to discuss a project, please see the Contact List on the back cover 3

4 Table of Contents Introduction... 3 Table of Contents... 4 Product System Uses... 5 Single Family Residential... 5 Multi-Family Residential... 5 Hospitality and Residence... 5 Mixed-Use Structures... 6 Mid-Rise and High-Rise... 6 Manufacturing and Commercial... 6 Office... 6 Building System Variations... 7 Bearing Wall Systems... 7 Frame Systems... 7 Floor and Roof Systems... 7 Product System Benefits... 8 Advantages of an EnCon Precast Hollow-core Building System... 8 Typical Design and Delivery Process... 9 Frequently Asked Questions What is hollow-core? How is hollow-core produced? What are the opening limitations in a hollow-core system? What sizes of hollow-core slab are available? What types of bearing systems are used with a hollow-core system? Span-Depth Ratios Typical Design Loads Minimum Bearing Load Tables HC Untopped Hollow-core Sections HC-Top Topped Hollow-core Sections HC Untopped Hollow-core Sections HC-Top Topped Hollow-Core Sections Detail Design Cross Section Details Section Properties Filled Cores Fire Rating or Resistance Common Details Hollow-core to Cast-in-Place Non-Load Bearing with Topping Hollow-core to Masonry Load Bearing with Topping Hollow-core to Masonry Load Bearing without Topping Hollow-core to Masonry Non-Load Bearing Hollow-core to Precast or Cast-in-Place Load Bearing with Shelf Angle (CIP) Hollow-core to Precast or Cast-in-Place Non-Load bearing Hollow-core to Precast Inverted Tee Beams Hollow-core to Precast L Beam Hollow-core to Steel Wide Flange with Reduce Structural Depth Hollow-core to Steel Wide Flange Hollow-core to Steel Wide Flange Alternate Hollow-core to Continuous Precast Load Bearing Wall Project Specifications (Sample) General Notes (Sample)

5 Product System Uses Single Family Residential EnCon s precast concrete hollow-core offers many benefits at a cost-effective price. Often, the space beneath a garage can be exploited by extending the basement walls to include the garage overhead. Setting hollow-core slabs on bearing walls forms the necessary fire separation and the perfect noise barrier. The slab serves as a ceiling for the lower level and creates a column-free area that can be used for storage or as functional living space. Hollowcore provides superior moisture control and protection from mold development and waterrelated damage. Multi-Family Residential EnCon s unique precast products can be used to create a parking garage underneath an apartment building, delivering protection and security. The floor slabs form fire separations and noise barriers between common areas and living spaces. These elements can be erected quickly, speeding construction time and reducing building cost. The design saves land costs while adding benefits for tenants and enhancing Lakefront long-term resale value. In addition, the floor design can accommodate multiple penetrations for mechanical equipment. Unlike wood and steel floor systems, hollow-core provides immediate access for other trades with minimal preparation for final conditions. Although not specific to multi-family residential construction, units with integral balconies can be produced so that all floor components are from a single source supplier. Hospitality and Residence Specialized housing, including hotels, motels, destination resorts, dormitories, assisted-living and nursing homes, in which smaller spaces combine with large banquet or meeting rooms, are aided by hollow-core slab s long spans, fast erection and allyear construction. Precast concrete is highly fire-resistant and an excellent material for compartmentalization as it slows the spread of fire, smoke, and noise between rooms and floors. Additional floor loading for special needs required by assistedliving facilities is easily, economically, and safely handled with a precast hollow-core floor system. The underside can act as a direct ceiling avoiding the need for drop ceilings or additional materials. The Broadmoor 5

6 Mixed-Use Structures Buildings commonly need to serve several purposes; one structure can house retail space, parking facilities, and residential units. A hollowcore precast floor and roof system provides noise and vibration isolation, fire separation and resistance, penetration flexibility, and structural support for small spaces above large open areas. Christina Landing Mid-Rise and High-Rise Vertical construction, such as hotels, motels, dormitories, mixed-use, and residential, in which shallow floor depths combine with open floor plans, can take advantage of hollow-core slab s long spans, fast erection, and all-year construction. Specialized beams of precast prestressed concrete or steel create shallow floor systems supported on precast columns. The lightweight nature of the product allows erection by tower crane, decreasing site congestion. Precast concrete s fire-resistance makes it an excellent material for tower construction by reducing the spread of fire, smoke, and noise between rooms and floors. Precast balconies can be integral components in the load bearing system. Manufacturing and Commercial Low-rise buildings, including manufacturing facilities, warehouses, distribution centers, food-processing plants, rapid-lube stores and car washes, benefit from the advantages offered by total precast concrete systems. Heavy load capacity, vibration resistance, durability, penetration flexibility, and nearly unlimited floor plan arrangements make this an ideal building system. Office Patriot Park Corporate managers enjoy the secure image and fast construction that precast concrete provides. It reduces interim financing costs and ensures that facilities will be ready for occupancy on schedule. In addition, precast concrete mass keeps heating and cooling costs down and lowers fire insurance rates for the end user. Precast hollow-core floor and roof systems create shallow structural depths often decreasing the total building height or allowing for an additional floor as compared to similar height structures. Correctional Facilities Due to its unique nature and occupancy requirements, a correctional facility traditionally has an intricate floor plan with heavy loads that are varied and complex from walls above. Hollow-core s high load capacity makes it an excellent building material for this kind of structure. Long spans means fewer support columns to act as obstacles, allowing for flexible floor plans as well as decreasing security risk and supervision constraints. 6 El Paso County Jail

7 Building System Variations Bearing Wall Systems Broadmoor Lakeside Bearing wall systems provide compartmentalization, outstanding fire safety between units, significant thermal benefit, and reduced noise transmission. Wellsuited for dwellings with multiple residents, these systems are traditionally used in the multi-family and the hospitality construction markets. Frame Systems For large open areas with long clear spans, a hollow-core frame system is ideal. Loft space has become a primary residential construction market, and a building utilizing a hollow-core construction system has a distinct advantage. With a shallow overall structural depth, building height can be reduced. This building system is traditionally used for office construction, but residential units are being developed, illustrating the growing popularity and varied uses of hollow-core floor systems. Giddings Lofts Floor and Roof Systems Complex geometry and floor plans are easily designed using a precast hollow-core system. Layouts can be adjusted to accommodate inconsistent or repetitive bearing geometries. Optimal use of the material can be achieved and minimal in-place forming requirements are primary benefits of a hollow-core system. Colorado Golf Clubhouse, Roof and Floor Plans 9

8 Product System Benefits Precast hollow-core provides a cost-effective efficient floor and roof system. The slabs facilitate the completion of a building in the least amount of time possible, at the most economical cost, without sacrificing quality or the integrity of the structure. Advantages of an EnCon Precast Hollow-core Building System EnCon s commitment to partnership, customer care, and product excellence. EnCon maintains a full service integrated approach to delivery, from design support to product installation. Clients receive the benefits and convenience of a single source supplier, which limits the project risk and the number of subcontracts needed. The EnCon Companies have delivered high quality precast concrete structures throughout the United States. In high seismic regions, a lighter weight floor plate weight decreases the lateral forces and subsequent foundation requirements. Topped or un-topped, a hollow-core system can be used as a lateral load diaphragm. Long spans with shallow sections allow for high span-to-depth ratios while reducing floor-to-floor heights. This results in more interior space with less obstruction from structural depth and columns. Design flexibility. Spaces without interior support columns can accommodate nearly any floor plan as well as enable the rendering of unusual or complicated details. Increased load capacity for floors. Greater quality control, consistency and finish with in-plant production. Plant production will also reduce onsite labor and lower the job site safety risk. The rapid construction process enables openings in the floor plate to be closed quickly, creating an immediate working platform for other trades concurrently working onsite. EnCon s precast components and systems can be erected in adverse weather conditions where other building systems may not. Long-term durability, requiring far less maintenance than conventional building materials. Excellent fire resistance and protection as well as vibration resistance. Moisture control, mold and mildew resistance, and insect proof. Acoustical control; reduced noise transmission between spaces for greater privacy. Thermal mass delivers superior energy efficiency - acts as a thermal sink to smooth peak heating and cooling demands; cross sections greatly reduce heat loss through roof. These inherent benefits help meet stricter energy requirements while providing less environmental impact. Hollow-core can provide natural channels for wiring conduit, heating, air conditioning, and plumbing. Offers finished ceilings that may be left exposed or painted. A delivered finished system eliminates need for suspended ceilings. Offers finished floors; with minimal leveling and finishing, the final surface may be directly applied. Enables owners and developers to remain competitive as it is a financially viable solution. 8

9 Typical Design and Delivery Process The flow chart below highlights the general process from project initiation to completion. The tables contain representative project schedules and demonstrate the primary scheduling benefit of precast concrete construction. There are a number of interrelated yet overlapping activities that allow faster turnaround and quicker job completion. Project Identification Preliminary Design Assistance Estimate and Award Project Final Design Calculations, Erection Drawings, and Details Submittal and Approval Process Manufacture, Store, and Transport Final Erection and Production Drawings Erection and Field Finish Project Completion 9

10 Frequently Asked Questions What is hollow-core? Hollow-core is a prestressed concrete flat slab containing continuous hollow voids that run throughout its length. Hollow-core is an ideal building material as it is lighter in weight and lower in cost than conventional cast-in-place concrete. Popular applications for hollowcore are floor and roof deck systems. What is prestressed concrete? Reinforced concrete members must carry their own weight as well as any applied loads. Conventional reinforced concrete slabs must have short spans and thick section depths. Prestressing overcomes this limitation by adding an internal force that counteracts the self-weight and loads that are applied. What is camber? Camber is a byproduct of an eccentric prestress force. Since the most economical placement of strand is at the bottom of the member, the prestress is below the center of gravity, (Not to Scale) causing the center of the member s span to bow up. The amount of camber is affected by a number of factors such as span, prestressing force, concrete strength, and curing variations. The erector will adjust bearing elevations of adjacent members to minimize camber between slabs. What is the finished surface of a hollow-core system? Since the product is machine produced, both the top and bottom surfaces are quite smooth. If the final surface is un-topped, a leveling compound can be used for finishing the joints and any unevenness between the slabs. If the top will be layered with a concrete topping, no additional surface preparation is required. Although smooth, the bond between field-placed topping and hollow-core provides enough strength for composite behavior if required. The underside can be used as a finished ceiling as installed and either left unfinished, painted, or coated with an acoustical spray. How is hollow-core produced? EnCon produces hollow-core through a dry cast extrusion or a slip form process. The manufacturing surface, or bed, is about 500 long, and with the use of a special machine, the product is extruded as one continuous slab. Prestress strand, the primary reinforcement, is installed and stretched prior to adding any concrete. Afterwards, the concrete can be placed with a mechanical slip or through extrusion. Hollowcore cures within 5 to 14 hours regardless of the manufacturing process used. The long single piece is marked into smaller pieces and saw cut with a large diamond-impregnated wet saw. The individual slabs are then numbered, inspected for dimensional accuracy, and stored until delivery. EnCon provides two types of hollow-core products, each having inherent advantages for different building solutions. EnCon Colorado produces hollow-core through a dry cast extrusion process. On a 500 long manufacturing bed, an Elematic machine generates a continuous 4 wide slab. Prestressed 12

11 strand serves as the primary reinforcing and is installed and pulled prior to extrusion of the concrete. Zero slump or dry (very stiff) concrete is placed after the reinforcing. Stresscon produces its Dynaspan product using a wet cast system. On a 485 long bed, the higher slump concrete is cast as a continuous 8 wide slab. Long tubes attached to the casting machine slip form the cores within the product. Again, prestressed strand serves as an efficient primary reinforcing. Pulling Strand Extrusion Saw Cutting Storage How is a hollow-core system installed? Hollow-core should be installed by skilled technicians with experience operating lifting devices and cranes. The slabs are to be positioned and connected to the structure in accordance with engineering calculations, drawings, and details. Other factors that should be considered in the erection of the system are: site access, crane access, sequence and starting position, as well as the results of a site survey to ensure proper elevations and building geometry. Delivery Lifting and Placement Welding Final Construction What are the opening limitations in a hollow-core system? Openings smaller than 12 x12 are generally installed in the field through a core drill process and if required the corners are squared off with a saw. Hammer drilled holes smaller than 2½ in diameter can be installed in nearly any location within the system. The locations of these openings should be coordinated with the EnCon Design Department so the primary reinforcement can be avoided. Most often, the design team (Contractor, Engineer of Record EOR, and Architect of Record AOR) is given a set of rules to follow which makes for simple trade coordination. Openings larger than 12 are added to the product in the plant and must follow the engineering and design requirements of the system. Larger openings can be accommodated though the use of hangers where the adjacent slabs support other shorter slabs. All openings are normally considered rough openings, but a finished opening can also be provided if needed. Plant Cut Penetration Flexibility Core Drill Header Steel 11

12 What sizes of hollow-core slab are available? Generally, finished products are nominally 4-0 or 8-0 which includes a nominal joint width. Narrower pieces can be produced with the narrowest being one complete core and two vertical ribs, but the length of the product will play a role in this dimension. For product lengths and spans, please see the Preliminary Design section. The available section thicknesses are 8 and 10 with thicker sizes available upon request. Each hollow-core panel provides certain advantages given the fabricated cross sections. The 4' Elematic product is lighter to ship and erect. It is beneficial for high-rise, high-density projects, where crane access and reach are limited. It is an ideal solution for multi-story structures where a tower crane is being used. The Elematic product also provides exceptional spanning capabilities, given its efficient cross section. The 8' Dynaspan product, while heavier per piece, supplies more square footage per panel. With fewer pieces to deliver and erect, the Dynaspan product may offer cost efficiencies for low- or mid-rise structures. EnCon will work with the design team early in the process to determine the most economical approach. What types of bearing systems are used with a hollow-core system? Hollow-core is a very versatile building system. Support can be provided by other precast sections (beams, walls, etc.,) steel sections, cast-in-place, and masonry. Total precast solutions are beneficial in terms of cost, scheduling, and construction-site impact. Details for a variety of load bearing materials plus connection concepts can be found in the Detail Design section. Masonry Steel Frame Cast-in-Place Precast Frame What are grout keys? Grout keys are spaces between hollow-core units. During the erection and installation processes, the grout key will be filled with a sand-cement grout. Within the key, straight and bent rebar is installed for structural integrity and diaphragm behavior. Multiple slabs, when grouted together, can act as one continuous floor or roof section. 14

13 Preliminary Design Span-Depth Ratios The PCI Design Handbook recommends limits on span-depth ratios for hollow-core systems. For roof members, a span-depth ratio limit of 50 is suggested. In practice, a span-depth ratio of 45 is common for floors and roofs where fire endurance, openings, or heavy or sustained live loads do not control a design. Structural topping plays an important role in the span-depth ratio. The design recommendations for span lengths vary slightly from cross section to cross section, but the following are general rules to consider in the preliminary design. Assuming a uniform superimposed load of 100 pounds per square foot and an un-topped system, these guidelines apply: Depth Factors such as concentrated loads and large openings can affect the span capabilities of a system. Once the given loadings, fire endurance ratings, span lengths, and slab thicknesses have been determined, load tables are consulted. Typical Design Loads Design loads are determined by applicable building codes, engineering judgment, and building use. The following guidelines may be used: Span 8 inches 30 feet 10 inches 40 feet 12 inches 46 feet Building Use Dead Load (psf) Live Load (psf) Residential floors Residential garage floors Office Office assembly space 100 Storage Mezzanine 125 Minimum Bearing Hollow-core units require a minimum of 2 of bearing. They are typically designed and detailed with a ⅛ -thick continuous bearing material. Often, as the slab gets longer, additional bearing length is detailed. This additional bearing length may be as large as 2, for a combined total of 4. For steel, bearing of 2 is recommended and for concrete surfaces, 3 is recommended. 13

14 Load Tables The following load tables are based on both topped (composite) and un-topped systems. Load spans are approximate and based on ACI The values are assumed to be service level live loads without the 1.6 multiplier. When the analysis of the section includes topping, the following topping parameters are used. 2 Composite thickness mid-span, an additional 25 psf dead load, and a 28-Day topping strength of 4000 psi. Product Code Description 4HC Quantity of ½ Diameter Strand Section Depth Section product code (HC-Hollow-core) Section width in feet Load Table Key Controlled by ductility 8-4 Controlled by ductility requirements requirements 8-4 Controlled Controlled by shear by shear 8-4 Controlled Controlled by flexure by flexure Strand fpu = ksi f'ci = 3500 psi f'c = 7000 psi Effective Pull Ratio = 0.75fpu 14

15 4HC Untopped Hollow-core Sections 4HC - Untopped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf) HC - Untopped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf)

16 4HC-Top Topped Hollow-core Sections Live Load (psf) 4HC - Topped SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) HC - Topped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf)

17 8HC Untopped Hollow-core Sections. 8HC - Untopped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf) HC - Untopped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf)

18 8HC-Top Topped Hollow-Core Sections. 8HC - Topped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf) HC - Topped Live Load SIMPLE SPAN IN FEET - CENTER TO CENTER OF END BEARINGS (ft) (psf)

19 Detail Design Cross Section Details The following detailed hollow-core cross sections are produced by EnCon and related companies. 4HC8 4HC10 4HC12 8HC8 8HC10 19

20 Section Properties Un-Topped 2 Composite-Topped Section (f`ctopping = 4000 psi) Area (in 2 ) Y b (in) I (in 4 ) Wt (psf) Y b (in) I (in 4 ) 4HC HC HC HC HC Filled Cores The majority of core ends are not filled. In multi-story construction it may be necessary to grout the cores to prevent crushing of the ends or to increase the shear capacity of the section. Filled cores are also common when longitudinal cuts leave large cantilevers of material. Welded Connections Most welded connections are used for steel beam stabilization during erection. Typically, this welded connection creates a laterally-braced system which increases the design strength of the steel section. Long term movement is not uncommon in both beam and slab members; therefore it is not recommended that welded connections exist on both ends of the same member. Contract Drawings and Information The following information should be provided: o o o o o o Span directions Loading requirements General loading Line load Point loading Diaphragm forces and lateral loads o o o o o o Conceptual connection information Supporting elements Fire resistance requirements Edge of slab geometry and grid layout Topping requirements Opening size and location Fire Rating or Resistance Fire ratings are based on a Rational Fire Design calculation method or an IBC Prescriptive Fire Rating method. A fire rating is dependent upon: equivalent thickness, heat transmission thickness, cover on the prestressing strand, and end restraint. A standard 8-inch thick hollow-core system has a 2-hour fire rating, but higher ratings (3- or 4-hour) may be achieved with topping and gypsum board or the application of a spray-on fire-resistant material to the underside of the slab. Camber Camber is inherent to prestressed hollow-core slabs and is a function of the amount of eccentric prestressing force needed to carry the superimposed design loads. Prediction of camber is determined using empirical formulas and is at best an estimate. Actual camber is usually higher than calculated values; calculated long-term values should be considered only as estimates. Non-structural components attached to members which could be affected by camber variations, such as partitions or folding doors, should be placed with adequate allowance for these variations. Calculation of topping quantities should also recognize the imprecision of camber calculations. Common Details 20

21 The details on the following pages are non-cross section specific and are applicable in standard bearing and non-bearing conditions. These are not the only design options available. Often they are used as starting points for job-specific section and detail requirements. Connection details will vary slightly depending on whether the slab was produced using a dry cast extrusion or a slip form technique. Designers are strongly encouraged to discuss potential details with the fabricator during design development. Hollow-core to Cast-in-Place Non-Load Bearing with Topping Continuation wall is erected or set in place after hollow-core is erected and grouted The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 21

22 Hollow-core to Masonry Load Bearing with Topping Continuation wall is erected or set in place after hollow-core is erected and grouted The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 22

23 Hollow-core to Masonry Load Bearing without Topping Continuation wall is erected or set in place after hollow-core is erected and grouted The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 23

24 Hollow-core to Masonry Non-Load Bearing The ripped end of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 24

25 Hollow-core to Precast or Cast-in-Place Load Bearing with Shelf Angle (CIP) The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 25

26 Hollow-core to Precast or Cast-in-Place Non-Load bearing Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 26

27 Hollow-core to Precast Inverted Tee Beams The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 27

28 Hollow-core to Precast L Beam The ends of the core may need to be filled for load transfer Topping thickness will vary based on the hollow-core camber Wall thickness will vary depending on EOR and AOR design requirements 28

29 Hollow-core to Steel Wide Flange with Reduce Structural Depth The ends of the core may need to be filled for load transfer Steel beam based on design loading and EOR requirements 29

30 Hollow-core to Steel Wide Flange The ends of the core may need to be filled for load transfer Steel beam based on design loading and EOR requirements 30

31 Hollow-core to Steel Wide Flange Alternate The ends of the core may need to be filled for load transfer Steel beam based on design loading and EOR requirements 31

32 32 Hollow-core to Continuous Precast Load Bearing Wall

33 Project Specifications (Sample) 1.01 SECTION INCLUDES A. Floor and roof slabs, related connection plates, brackets, hangers, and grouting of joint keys RELATED SECTION A. Section Structural Precast Concrete REFERENCES A. ACI 301 Structural Concrete for Buildings. B. ACI 318 Building Code Requirements for Structural Concrete. C. ASTM A36 Structural Steel. D. ASTM A153 Zinc Coating on Iron and Steel Hardware. E. ASTM A416 Uncoated Seven-Wire Stress-Relieved Steel Strand for Prestressed Concrete. F. ASTM A615 Deformed and Plain Billet-Steel Bars for Concrete Reinforcement. G. ASTM A666 Austenitic Stainless Steel, Sheet, Strip, Plate, and Flat Bar for Structural Applications. H. ASTM C150 Portland Cement. I. ASTM C Fly Ash. J. ASTM C33 -- Aggregates. K. ASTM C260 Air Entrainment Admixtures. L. ASTM C494 Water Reducing Agents. M. AWS D1.1 Structural Welding Code. N. AWS D1.4 Structural Welding Code Reinforcing Steel. O. PCI Manual For The Design of Hollow Core Slabs. P. PCI MNL-116 PCI Structural Quality Control Manual. Q. PCI MNL-120 PCI Design Handbook. R. PCI MNL-123 PCI Connections Manual. S. PCI MNL-124 PCI Design for Fire Resistance of Precast Prestressed Concrete. T. PCI MNL-127 PCI Erection Tolerances. U. PCI MNL-135 Tolerances for Precast and Prestressed Concrete. V. IBC International Building Code DESIGN REQUIREMENTS A. Size components to withstand design loads. B. Concrete: Minimum compressive strength of 5000 psi at 28 days and 3500 psi at release. C. Design components to accommodate construction tolerances, deflection of other building structural members and clearances of intended openings. D. Grouted Keys; Capable of transmitting horizontal shear force of 80 psi. E. Calculate structural properties of framing members in accordance with ACI SUBMITTALS A. Shop Drawings: Indicate slab locations, unit identification marks, connection details, edge conditions, bearing requirements, support conditions, dimensions, openings, openings intended to be field cut, and relationship to adjacent materials. B. Product Data: Indicate standard component configuration, design loads, deflections, and cambers. C. Fabricator s Installation Instructions: Indicate special procedures and perimeter conditions requiring special attention QUALITY ASSURANCE A. Perform work in accordance with the requirements of PCI MNL-116, PCI MNL-123, and PCI MNL-120. B. Maintain plant records and quality control program during production of precast slabs. Records available upon request QUALIFICATIONS A. Fabricator: Company specializing in manufacturing the work of this section and PCI certified. B. Erector: Company specializing in erecting the work is recommended. C. Design precast concrete members in accordance with PCI Manual For The Design of Hollow Core Slabs, under direct supervision of a Professional Structural Engineer experienced in design of this work and licensed in the state of the project. D. Welder: Qualified in accordance with AWS D REGULATORY REQUIREMENTS A. Conform to ACI 318 code for design load and on-site construction requirements. B. Conform to PCI MNL-124, PCI MNL-116, and PCI MNL PRE-INSTALLATIONCONFERENCE 33

34 A. Discuss anchor and weld plate locations, sleeve locations, and cautions regarding cutting or core drilling DELIVERY, STORAGE, AND HANDLING A. Lifting or Handling Devices: Capable of supporting member in positions anticipated during manufacture, storage, transportation, and erection. B. Mark each member with production identification and orientation (if required.) 1.12 COORDINATION A. Coordinate work under provisions of separate section FABRICATORS PCI Certified Plant 2.02 MATERIALS A. Materials: To be in conformance with ACI 318. B. Tensioning Steel Tendons: ASTM A416 Grade 270. C. Reinforcing Steel: ASTM A615 or A706, deformed steel bars. D. Sand - Cement Grout: Sufficient for placement and hydration ACCESSORIES A. Connecting and Supporting Devices: Conform to PCI MNL-120 plates, angles, items cast into concrete, items connected to steel framing members, and inserts; ASTM A36 carbon steel. B. ⅛ bearing material FABRICATION A. Conform to AWS D1.4 and PCI MNL-116. B. Embed anchors, inserts, plates, angles, and other items at locations indicated. C. Provide openings required by other sections at locations indicated. Greater than 12 inches square or in diameter COMPONENTS A. Nominal Thickness: 8 or 10 inches. B. Nominal Width: 48 or 96 inches FINISHES A. Plant Finish: Finish members to PCI MNL-116 Finish B Grade FABRICATION TOLERANCES A. Conform to PCI MNL-116 and PCI MNL SOURCE QUALITY CONTROL AND TESTS A. Provide testing and analysis of site-placed concrete and grout under provisions of Section B. Maintain shop inspection and testing reports for stressing tendons. C. Test samples in accordance with specified ASTM and ACI standards. 3.0 ERECTION A. Erect members without damage to structural capacity, shape, or finish. Replace or repair damaged members. B. Align and maintain uniform horizontal and end joints as erection progresses. C. Install bearing material or shims at bearing ends of slabs as indicated or necessary. D. Adjust differential camber between precast members to tolerance before final attachment and grouting. E. Adjust differential elevation between precast members to tolerance before final attachment. F. Secure units in place. Grout slab and joints or perform welding in accordance with AWS D ERECTION TOLERANCES A. Erect members level and plumb within allowable tolerances. B. All work to conform to PCI MNL-127 and PCI MNL PROTECTION OF FINISHED WORK A. Protect members from damage from other trades by General Contractor throughout the job. 32