14 March 2016 City Hall Station Renovations Bid Documents 15 th Street Station Phase Station Improvements SECTION PRECAST CONCRETE

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1 SECTION PRECAST CONCRETE PART 1 GENERAL 1.01 DESCRIPTION A. The work specified in this Section consists of designing, furnishing and installing precast concrete components RELATED SECTIONS A. Section Submittals. B. Section Quality Requirements. C. Section Concrete Reinforcement. D. Section Cast-in-Place Concrete. E. Section Structural Steel. F. Section Metal Fabrications REFERENCE STANDARDS A. American Association of State Highway and Transportation Officials (AASHTO): 1. Standard Specifications for Transportation Materials and Methods of Testing and Sampling: a. AASHTO M Standard Specification for Plain and Laminated Elastomeric Bridge Bearings. B. American Concrete Institute (ACI): 1. ACI Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass Concrete. 2. ACI Specifications for Structural Concrete. 3. ACI 318/318R - Building Code Requirements for Structural Concrete and Commentary. C. ASTM International (ASTM): 1. ASTM A36/A36M, Standard Specification for Carbon Structural Steel. 2. ASTM A82/A82M Standard Specification for Steel Wire, Plain, for Concrete Reinforcement. 3. ASTM A123/A123M, Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products. 4. ASTM A615/A615M - Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement. 5. ASTM A775: Standard Specification for Epoxy-Coated Steel Reinforcing Bars 6. ASTM C31/C31M - Standard Practice for Making and Curing Concrete Test Specimens in the Field. 7. ASTM C33 - Standard Specification for Concrete Aggregates. 8. ASTM C39/C39M - Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens. Precast Concrete

2 9. ASTM C109/C109M - Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens). 10. ASTM C143/C143M - Standard Test Method for Slump of Hydraulic-Cement Concrete. 11. ASTM C150 - Standard Specification for Portland Cement. 12. ASTM C171 - Standard Specification for Sheet Materials for Curing Concrete. 13. ASTM C173/C173M - Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method. 14. ASTM C192/C192M - Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory. 15. ASTM C231 - Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method. 16. ASTM C309 - Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete. 17. ASTM C494/C494M - Standard Specification for Chemical Admixtures for Concrete. 18. ASTM C942 - Standard Test Method for Compressive Strength of Grouts for Preplaced- Aggregate Concrete in the Laboratory. 19. ASTM C1064/C1064M Standard Test Method for Temperature of Freshly Mixed Hydraulic-Cement Concrete. 20. ASTM D412 Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers Tension. 21. ASTM D2240 Standard Test Method for Rubber Property Durometer Hardness. D. National Precast Concrete Association (NPCA): 1. NPCA Plant Certification Program. 2. NPCA Quality Control Manual for Precast Concrete Plants. E. Precast/Prestressed Concrete Institute (PCI): 1. PCI MNL Manual for Quality Control for Plants and Production of Structural Precast Concrete Products. 2. PCI MNL Manual for Quality Control for Plants and Production of Architectural Precast Concrete Products. 3. PCI MNL-120 Architectural Precast Concrete. 4. PCI MNL-135 Tolerance Manual for Precast and Prestressed Concrete Construction SUBMITTALS A. Product Data: 1. Precast concrete unit anchorage, lifting inserts, and other devices 2. Mechanical splice sleeves. 3. Bearing pads. 4. Accessory items. B. Shop Drawings: 1. Precast concrete units, layout (installation) drawings, and reinforcement. Show complete design, installation, and construction information including details of steel reinforcement size and placement. 2. Manufacturer s handling and installation methods for products. Precast Concrete

3 C. Certificates: 1. Material certifications. D. Concrete Mix Design Submittals: 1. Concrete mix design proportions and concrete mix design test data. E. Precast Concrete Unit Design Submittal: 1. Precast concrete unit design calculations. Calculations shall include the analysis of units for lifting stresses and the sizing of lifting devices. 2. Structural design calculations shall be prepared and sealed by a Professional Engineer licensed in the Commonwealth of Pennsylvania. F. Qualification Statements: 1. Precast concrete manufacturing plant s quality control procedures or verification of the plant s current NPCA Plant Certification. G. Independent Quality Assurance Testing and Inspection Agency: The Contractor must employ the services of a qualified Independent Quality Assurance Testing and Inspection Agency (Agency). 1. Contractor shall coordinate with the requirements of the special inspections program as identified in Section The Agency shall be submitted for approval prior to proceeding with the work. The Agency shall have recent experience acceptable to the SEPTA Project Manager in the testing and inspection of similar projects. The SEPTA Project Manager reserves the right to reject any Agency deemed to be insufficiently qualified. H. Test Report 1. Slump test reports. 2. Compressive Strength test reports. 3. Air Content test reports QUALITY ASSURANCE A. Qualifications: 1. Plant-Precast Structural Concrete Manufacturer s Qualifications: a. Experience: 1) Employ an experienced and acceptable precast concrete manufacturer to design and fabricate the precast concrete units. 2) The precast concrete unit manufacturer must maintain a permanent quality control department, or retain an independent testing agency on a continuing basis. a) If an independent testing agency has been retained, the agency must issue a report, signed and sealed by a Professional Engineer licensed in the Commonwealth of Pennsylvania, detailing the ability of the precast concrete manufacturer to produce quality units consistent with industry standards. 3) Submit documentation showing the precast structural concrete manufacturer has been regularly and continuously engaged in manufacturing structural precast concrete similar to those required under this Contract for at least 5 years. b. Plant Certification Requirements: Precast Concrete

4 1) The precast manufacturer must be certified by the NPCA Plant Certification Program and must meet the requirements of PCI MNL-116 and/or PCI MNL- 117 as applicable. 2) The precast manufacturer must have quality control procedures established in accordance with the NPCA Quality Control Manual for Precast Concrete Plants in place prior to and during production of the products for this Contract. 3) Submit the plant s quality control procedures demonstrating adherence to the NPCA Quality Control Manual for Precast Concrete Plants, or verification of the plant s current NPCA Plant Certification. 2. Professional Engineer Qualifications: a. Have the precast concrete manufacturer employ a licensed Professional Engineer, registered in the Commonwealth of Pennsylvania, who has experience performing precast structural concrete calculations to design the standard precast concrete units and prepare Shop Drawings. B. Certifications: 1. Material Certifications: a. Submit copies of material certifications and laboratory test reports from the precast concrete manufacturer for the Portland Cement, aggregates, admixtures, and curing compound proposed for the Work of this Section. b. For reinforcement steel material, submit certified copies of mill test. C. Mock-Ups: 1. Because color variations and surface imperfections are not always apparent on small scale samples, a full-size mock-up of the concrete finishes are required for approval prior to starting production. a. The approved mock-up shall be used as the standard for the aesthetic quality of the surface finish; it shall be the Control Sample 2. The Project Manager will visit the precast manufacturer to inspect the plant and the mockup sample DELIVERY, STORAGE, AND HANDLING A. Delivery and Acceptance Requirements: 1. Ensure adequate access to the Site is available to enable hauling, storage, and proper handling of the precast concrete units. 2. Do not ship precast concrete units that do not meet the specified criteria. 3. Transport precast concrete units in a manner that minimizes potential damage. 4. Each precast concrete will be examined unit as it is delivered to the Site for quality and acceptance; unacceptable units will be rejected. B. Storage and Handling Requirements: 1. Employ lifting methods and devices intended for the purpose as indicated on the approved Shop Drawings. a. Submit manufacturer s information showing acceptable handling methods for the products. b. Lift precast concrete units at points provided by the precast concrete manufacturer using suitable lifting devices. c. Consistent with industry standards, furnish lifting devices having a minimum factor of safety of 4. 1) Furnish reusable lifting hardware and rigging having a minimum factor of safety of 5. Precast Concrete

5 2. Store and handle precast concrete units in a manner that will minimize potential damage. a. Do not place units directly on the ground. PART 2 PRODUCTS 2.01 DESIGN CRITERIA A. Concrete Compressive Strength: 1. Provide precast concrete units having a minimum 28-day compressive strength (f c) of 5000 psi. B. Precast Concrete Units: 1. Have the Professional Engineer employed by the precast concrete manufacturer perform the following tasks: a. Verify the precast concrete units can withstand the stresses induced during shipping, handling, and installation in order to avoid product cracking or other handling damage. b. Develop the complete analysis for lifting stresses, the sizing of lifting devices, and foundation attachment. c. Determine the concrete mix design proportions. 1) Submit a mix design for each strength and type of concrete to be used. a) Include copies of concrete mix design test reports complying with the requirements of Section 4 in ACI 301 showing the mix has successfully produced concrete with the specified properties, and will be suitable for Contract conditions. b) Provide the quantity, type, and brand of all mix design constituents in the design, and include applicable data sheets for each constituent. d. Prior to fabricating the precast concrete units, prepare Shop Drawings for the precast concrete units showing complete design, installation, and construction information. 1) Include details showing the size and placement of steel reinforcement. 2) Indicate the type and configuration of joints and sealants between adjacent units. 3) Include plans and elevations showing dimensions, connection details, finishes, openings, cast-in-place items, and the erection sequence. 2. Submit the precast concrete unit Shop Drawings and design calculations, prepared, stamped, and signed by the Professional Engineer. 3. Precast concrete units shall utilize epoxy-coated reinforcing steel (Note: Applies to precast concrete only. See for cast-in-place requirements) MATERIALS A. Cement: 1. Type I or II cement complying with the requirements of ASTM C For all exposed precast concrete use the same brand, type, and source of cement. Precast Concrete

6 B. Normal Weight Concrete Coarse and Fine Aggregates: 1. Aggregates complying with the requirements of ASTM C Do not provide aggregates that contain substances which may be deleteriously reactive with the alkalis in the cement. C. Admixtures: 1. Accelerating, Retarding, Water-Reducing Admixtures: a. Provide accelerating, retarding, water-reducing (moderate to high) admixtures complying with the requirements of ASTM C494/C494M. D. Water: 1. Potable water or water clean and free of injurious amounts of oils, acids, alkalis, salts, and other substances deleterious to concrete and concrete reinforcement. E. Crystalline Waterproofing Additive: Add crystalline waterproofing to all concrete used in precast panel construction. 1. Concrete waterproofing system shall be of the crystalline type that chemically controls and permanently fixes a non-soluble crystalline structure throughout the capillary voids of the concrete. The system shall cause the concrete to become sealed against the penetration of liquids from any direction and protect the concrete from deterioration due to harsh environmental conditions. 2. Dosage rate to be 2% (Xypex, Sika WT-215 P) 1% (Penetron Admix) of the total cementitious material content. Dosage rate shall be in accordance with waterproofing admixture manufacturer s recommendations. Add crystalline admixture at the batch plant. 3. Acceptable Manufacturers: a. Xypex ( b. ICS Penetron ( c. Sika WT-215 P d. Or approved equal. F. Corrosion Inhibitor: See Specification G. Concrete Reinforcement: 1. Reinforcement Bars: ASTM A615, Grade 60, deformed steel with epoxy coating conforming to ASTM A775. a. Damaged epoxy coating shall be repaired with in conformance with ASTM A Wire: a. ASTM A82, Epoxy coated. H. Inserts and Embedded Metal: 1. Provide inserts and embedded metal items of the type required for the intended use that comply with the following: a. Provide structural steel plates, angles, and other shapes complying with the requirements of ASTM A36/A36M. b. Hot-dip galvanize items in accordance with the requirements of ASTM A123/A123M. c. Provide proprietary items in accordance with the manufacturer s published literature. I. Structural Steel Plates and Shapes: 1. Plates and shapes conforming to requirements of ASTM A36/36M. 2. Hot-dip galvanized items in conformance with ASTM A123/A123M. Precast Concrete

7 J. Anchorage, Lifting Inserts, and Devices: 1. For the precast concrete unit anchorage, lifting inserts, and other devices, submit Product Data sheets and proper installation instructions from the precast concrete manufacturer for approval. a. Clearly indicate precast concrete unit dimensions. b. Clearly indicate safe working loads. K. Bearing Pads: 1. Provide a multi-polymer plastic shim pad impervious to liquids, alkalis, and microorganisms that provides load-bearing surface contact. a. Compressive Strength: 8000 psi minimum with no fracture at 26,000 psi. b. Coefficient of linear expansion: 3 to 5 x 10-5 inches/ inch/ºc. 2. Manufacturers: a. Dayton Superior. b. JVI. c. Or approved equal. L. Preformed Expansion Joint Filler: See Section FABRICATION A. Shop Fabrication: 1. The precast concrete producer must conform to the requirements of the NPCA Quality Control Manual for Precast Concrete Plants. 2. Concrete Forms: a. Provide forms for manufacturing precast concrete units of the type and design consistent with industry standards and practices. 1) Provide forms capable of consistently providing uniform products and dimensions. 2) Construct the forms so the forces and vibrations to which the forms will be subjected cause no damage to the precast concrete unit. b. Clean concrete build-up from the forms after each use. c. Apply release agents to the forms according to the manufacturer s recommendations, but do not allow release agent to build-up on the form s casting surfaces. 3. Concrete Reinforcement: a. For placing and splicing, conform to ACI 318/318R. b. Provide concrete cover on the reinforcement as shown on the Contract Drawings. c. Fabricate cages of reinforcement by tying the bars into rigid assemblies. d. Position the reinforcing as specified by the design so the concrete cover conforms to the requirements. e. Provide positive means to assure the reinforcement does not move significantly during the casting process. f. Do not use metal chairs along exposed face of member. 4. Embedded Items: a. Position embedded items at the locations indicated in the Contract Documents and approved Shop Drawings. b. Hold inserts, plates, lifting devices, and other items to be embedded in the precast concrete rigidly in place so they do not move during casting operations. 5. Concrete: a. Mixing Concrete: 1) Perform mixing operations so the concrete produced is uniform in strength, consistency, and appearance. Precast Concrete

8 b. Placing Concrete: 1) Deposit conventional concrete in the forms as near to the final location as practical. 2) Consolidate concrete so segregation of the concrete and the creation of honeycombed areas are minimized. a) Furnish vibrators for consolidating the concrete having frequencies and amplitudes sufficient to produce well-consolidated concrete. c. Curing Concrete: 1) Commence curing operations immediately following the initial set of the concrete and of surface finishing. 2) Using one of the following methods, prevent moisture from evaporating from exposed surfaces until adequate strength for stripping the precast concrete unit from the forms is reached: a) Cover the concrete with polyethylene sheets using sheets as specified in ASTM C171, or b) Cover the concrete with burlap or another absorptive material and keep the material moist, or c) Apply a membrane-curing compound as specified in ASTM C309 at a rate not exceeding 200 square feet per gallon, or in accordance with the manufacturer s recommendations. 6. Stripping Precast Concrete Units from Forms: a. Do not remove precast concrete units from the forms until the concrete reaches the compressive strength required by the design for stripping. b. If no such requirement exists, products may be removed from the forms after the final set of concrete provided stripping does not have an effect on performance or appearance of the final product. 1) Routinely measure the stripping strengths to ensure the product has attained sufficient strength for safe handling. B. Fabrication Tolerances: 1. Provide precast concrete units conforming to the unit tolerances specified in PCI MNL MIXES A. Concrete Mix Design: 1. Concrete Proportions: a. Base the selection of concrete proportions on the methodology presented in ACI for normal weight concrete. b. Develop concrete proportions using the same type and brand of cement, the same type and gradation of aggregates, and the same type and brand of admixture. c. Do not use accelerators containing calcium chloride in precast concrete containing reinforcing steel or other embedded metal items. 2. Water-Cement Ratio: a. Provide concrete mixes having a water-cement ratio of 0.45 or less. 3. Air Content: a. Provide concrete mixes having a total air content of 6 percent plus or minus 1 percent by volume FINISHES A. Shop Finishing Methods: 1. If no finishing procedure is specified, finish concrete surfaces using a strike-off at the level of the top of the form; otherwise finish unformed surfaces of precast concrete products as specified: Precast Concrete

9 a. Formed Non-Architectural Surfaces: 1) Cast surfaces against approved forms in accordance with standard industry practices for cleaning forms, designing concrete mixes, placing concrete, and curing concrete. 2) Normal color variations, form joint marks, small surface holes caused by air bubbles, and minor chips and spalls will be accepted. 3) Major imperfections, excessive honeycombing, and other major defects are unacceptable. 4) Provide a rubbed finish to vertical surfaces of precast beams, piers, and platforms exposed to view. See Specification for surface finish requirements. b. Unformed Surfaces: 1) Finish unformed surfaces with a vibrating screed, or by hand with a float. 2) Normal color variations, minor indentations, and minor chips and spalls will be accepted. 3) Major imperfections, excessive honeycombing, and other major defects are unacceptable. 4) Provide a broom finish to top surface of the precast platform and stair elements. See Section for surface finish requirements. c. Light Sand-Blasted Finish 1) Provide a light sand blasting to remove the skin from the concrete surface to achieve a sand-textured surface. 2) Perform the finishing in accordance with industry standards or supplier specifications. 3) Use an abrasive grit of proper type and gradation to duplicate the Control Sample mock-up SOURCE QUALITY CONTROL A. Tests and Inspections: 1. During the period when precast concrete is being placed, the Independent Testing and Inspection Agency must perform routine and other testing of materials. The Agency shall submit reports directly to the SEPTA Project Manager. a. Advise the Independent Testing and Inspection Agency sufficiently in advance of operations to allow testing and inspection personnel to be assigned and to provide sufficient time for quality tests to be performed and completed. b. Provide and maintain adequate and separate facilities for safe storage and proper curing of concrete test cylinders. c. Provide containers for transporting concrete test cylinders to the testing laboratory. 2. Tests: a. The precast concrete manufacturer must demonstrate the following quality control tests are performed as required in accordance with the specified ASTM International standards by submitting test reports documenting compliance with the following tests: b. Slump Test: 1) Test Procedure: a) Perform a slump test in accordance with the requirements of ASTM C143/C143M either for each 50 cubic yards of concrete produced for each mix design, or once a day, whichever comes first. 2) Acceptance Criteria: a) Slump of up to 4 inches is acceptable unless a high range reducing admixture is used, in which case slump up to 8 inches is acceptable. c. Compressive Strength Test: 1) Test Procedure: Precast Concrete

10 a) For each mix design, perform a compressive strength test on at least 4 specimens for each 50 cubic yards of concrete produced for each mix design. (1) Test 2 cylinders at 7 days and 2 cylinders at 28 days. b) Perform a compressive strength test in accordance with the requirements of ASTM C39/C39M. 2) Acceptance Criteria: a) Mixes having the 28-day compressive strength (f c) as specified in Subparagraph 2.01.A are acceptable. d. Air Content Test: 1) Test Procedure: a) Perform an air content test in accordance with the requirements of either ASTM C231 or ASTM C173/C173M for each 50 cubic yards of concrete produced for each mix design, but not less than once a day. 2) Acceptance Criteria: a) Concrete having the air content as specified in for each mix design as specified in Subparagraph 2.04.A are acceptable. 3. Inspections: a. An inspector may be placed in the precast concrete unit manufacturing plant when the units provided under this Section are being manufactured. B. Non-Conforming Work: 1. Repairing Minor Defects: a. Products having defects that will not impair the functional use or expected life of a precast concrete unit may be repaired by an approved method that does not impair the product. 1) Formed surfaces relatively free of air voids and honeycombed areas do not require patching and repair unless the surfaces are required to be finished by the design or are exposed to public view. 2) Submit the materials and methods proposed for repairing surface defects for approval. 2. Repairing Honeycombed Areas: a. Where honeycombed areas are to be repaired, remove all loose material and cut back the areas to essentially horizontal or vertical planes. 1) Cut back the areas to a depth where coarse aggregate particles break under chipping rather than being dislodged. b. Use proprietary repair materials in accordance with the manufacturer s instructions to fill the depression. c. If proprietary repair materials are not used, saturate the area with water immediately prior to starting the repair. 1) Make sure the repair area is damp but free of excessive water. 2) Apply a cement-sand grout or an approved bonding agent to the chipped surfaces, followed immediately by consolidating an appropriate repair material into the cavity. 3. Repairing Major Defects: a. Have qualified personnel evaluate defects in precast concrete products which impair the functional use or the expected life of the products to determine if repairs are feasible, and if so, to establish the repair procedure. 4. Finish Requirements: a. Repair and patching work must comply with finish requirements of the Contract for the item. 1) Colors of repaired and patched work must reasonably match the colors specified for the work and/or surrounding areas. C. Coordination of Other Tests and Inspections: Precast Concrete

11 1. Notify the Testing and Inspection Agency responsible for performing special inspections when concrete for this Contract is being mixed, placed, and/or tested. 2. Cooperate with the Testing and Inspection Agency when they are performing required material verifications and other special inspections. a. Provide full access to the Work. PART 3 EXECUTION 3.01 EXAMINATION A. Verification of Conditions: 1. Verify the structure and anchorage inserts for the precast members to be placed are within the allowable tolerances. B. Evaluation and Assessment: 1. Notify the Project Manager of out of tolerance anchorage inserts for the precast members PREPARATION A. Protection of In-Place Conditions: 1. Erect adequate barricades, warning lights, and/or signs to safeguard traffic in the immediate area of hoisting and handing operations ERECTION A. Erect precast concrete units to the lines and grades indicated in the Contract Documents or as otherwise specified. B. Fasten the precast concrete units in place in accordance with the approved Shop Drawings. 1. Submit the precast concrete unit manufacturer s installation instructions for information. C. Furnish and maintain temporary bracing in place for the precast concrete units until final support and bracing is provided to maintain position, stability, and alignment. D. Special Techniques: 1. Field modifications to the precast concrete units are not allowed unless approved by the precast unit manufacturer and the Project Manager. E. Tolerances: 1. Furnish, erect, and interface precast concrete members within the tolerances specified for the applicable element type in PCI MNL REPAIR/RESTORATION A. The repair of damage occurring to the precast concrete units after installation is the responsibility of the Contractor. 1. Repairs made to exposed surfaces must match the color and texture of the surrounding concrete SITE QUALITY CONTROL A. Site Tests and Inspections: Precast Concrete

12 1. During the period when precast concrete is being erected, the Independent Testing and Inspection Agency must perform testing and inspections. The Agency shall submit reports directly to the SEPTA Project Manager. a. Advise the Testing and Inspection Agency sufficiently in advance of operations to allow testing and inspection personnel to be assigned and to provide sufficient time for quality tests to be performed and completed. b. Cooperate with the Testing and Inspection Agency to facilitate their testing and inspections. c. Failure of the Testing and Inspection Agency to detect defective work will not prevent its rejection later when the defect is discovered. 2. Inspections: a. Observe the lines and grades of installed units to verify they are correct. B. Non-Conforming Work: 1. Notify the precast concrete erector of observed discrepancies between the lines and grades of installed units and those indicated in the Contract Documents so corrective action can be taken CLEANING A. Clean soiled precast concrete surfaces, taking care to prevent damage to the surfaces and surrounding materials PROTECTION A. Immediately after the precast concrete units are erected, protect the units from damage. END OF SECTION Precast Concrete