Special Provision No. 999S28 June 2010 CONSTRUCTION SPECIFICATION FOR PRECAST PANELS FOR USE AS STAY-IN-PLACE DECK FORMS

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1 PRECAST PANEL STAY-IN-PLACE DECK FORMS FABRICATION Item No. PRECAST PANEL STAY-IN-PLACE DECK FORMS DELIVERY Item No. PRECAST PANEL STAY-IN-PLACE DECK PANELS ERECTION Item No. Special Provision No. 999S28 June 2010 CONSTRUCTION SPECIFICATION FOR PRECAST PANELS FOR USE AS STAY-IN-PLACE DECK FORMS 1.0 SCOPE This Special Provision covers the requirements for the fabrication, transportation and installation of precast concrete panels for use as stay-in-place forms for cast-in-place deck slabs supported by girders. 2.0 REFERENCES This Special Provision references the following standards, specifications, and publications: Ontario Provincial Standard Specifications, Construction: OPSS 904 OPSS 905 OPSS 929 OPSS 932 Concrete Structures Steel Reinforcement for Concrete Abrasive Blast Cleaning Concrete Construction Crack Repair - Concrete Ontario Provincial Standard Specifications, Material: OPSS 1202 OPSS 1350 Bearings Elastomeric Plain and Steel Laminated Concrete - Materials and Production American Society for Testing and Materials Standards: ASTM C ASTM C Standard Test Method For Microscopic Determination of Parameters of the Air-Void System in Hardened Concrete Standard Test Method for Electrical Indication of Concrete s Ability to Resist Chloride Ion Penetration Canadian Standards Association Standards: CAN/CSA A /A CAN/CSA A CSA G40.20/G CSA G164-M92 (R1998) Concrete Materials and Methods of Concrete Construction/Methods of Test for Concrete Precast Concrete Materials and Construction General Requirements for Rolled or Welded Structural Quality Steel/Structural Quality Steels Hot Dip Galvanizing of Irregularly Shaped Articles 3.0 DEFINITIONS For the purpose of this Special Provision, the following definitions apply: June 2010 Pg. 1 of 10 SSP999S28

2 Member: means a precast concrete prestressed girder. Lot: means all members in one bed which are of the same type. 4.0 DESIGN AND SUBMISSION REQUIREMENTS 4.01 Design Requirements Lifting Loops The Precaster is responsible for the design of the lifting loops for the panels. Lifting loops shall be stainless steel and shall have adequate capacity and be located such that the stresses in the panel due to stripping and handling are minimized. Lifting loops shall not project above the top layer of reinforcing in the cast-in-place portion of the completed deck slab. Lifting loops shall remain in place after the panels have been erected Support System for the Panels Angles or timbers, when used as support system for the panels, shall be designed by the Contractor or Precaster and shall support a temporary construction live load of 2.4 kpa applied to the top surface of the deck panel Reinforcing Steel Reinforcing steel shall be as detailed on the Contract Drawings Prestressing Strand Prestressing strands shall be placed at a uniform spacing and at the mid-depth of the panel. When releasing the strands, the prestressing force shall be applied uniformly and in a symmetrical manner to ensure that the panels do not crack. For prestressed panels, the ratio of panel thickness to strand diameter shall not be less than Submission Requirements Working Drawings The Contractor shall submit 3 sets of fabrication Working Drawings to the Contract Administrator at least 7 Days prior to commencement of fabrication of the panels, for information purposes only. Prior to making a submission, the seals and signatures of a design Engineer and a design-checking Engineer shall be affixed on the Working Drawings verifying that the drawings are consistent with the Contract Documents. Where multi-discipline engineering work is depicted on the same Working Drawing and the design or designchecking Engineer or both are unable to seal and sign the Working Drawing for all aspects of the work, the drawing shall be sealed and signed by as many additional design and design-checking Engineers as necessary. The Working Drawings shall include the following information: a) Panel dimensions, panel layout, and panel markings for the total bridge. b) Prestressing strand and/or reinforcement for the panels. June 2010 Pg. 2 of 10 SSP999S28

3 c) Jacking force, when prestressing is used. d) Lifting loops. e) Bearing strips. f) Support system, when used. g) All other applicable details. The supporting documents shall include stamped calculations for handling and erection procedures Modifications to Bridge Components At least one (1) week prior to commencement of fabrication of the components requiring modification, the Contractor shall submit to the Contract Administrator three (3) sets of drawings, for information purposes only, signed and sealed by an Engineer. The drawings shall show details of any required modifications to bridge components that are shown in the Contract Drawings, including but not limited to the following: a) Revised bearing seat elevations and/or bridge profile grade. b) Revised girder stirrup heights or shear connector spacing and heights. c) Revised reinforcement details for the deck slab Concrete Mix Design The Contractor shall be responsible for the concrete mix design and shall submit the concrete mix design to the Contract Administrator according to the Mix Design requirements of OPSS 1350 along with the certificate of ready mix concrete facilities when concrete is supplied by an external concrete supplier. The Contractor shall demonstrate, at the time of submission of the concrete mix design(s), that the proposed mix design(s) and materials are capable of meeting the requirements of this Special Provision. To demonstrate this, the Contractor shall submit test data for the following: a) 28-Day compressive strength. b) Air void system in the hardened concrete. c) For high performance concrete, rapid chloride permeability at 28 days. The precast concrete plant certificate as required by CAN/CSA A23.4 shall be submitted to the Contract Administrator as part of the concrete mix design submission Certificate of Conformance Upon completion of the panels and prior to delivery, the Quality Verification Engineer (QVE) shall conduct an interim inspection to verify that the fabrication of the panels has been carried out in general conformance with the Working Drawings, supporting documents and Contract Documents. June 2010 Pg. 3 of 10 SSP999S28

4 Upon completion of fabrication, delivery and erection and prior to placing the concrete for the cast-in-place portion of the deck slab, the Contractor shall submit to the Contract Administrator a Certificate of Conformance, sealed and signed by the Quality Verification Engineer. The certificate shall state that the fabrication, handling and erection of the panels have been carried out in general conformance with the Working Drawings, supporting documents, and Contract Documents. 5.0 MATERIAL 5.01 Concrete Concrete materials and production shall be according to OPSS 1350 with the following exceptions: a) The requirements for hardened air void system parameters, rapid chloride permeability and compressive strength do not apply. b) Compressive strength shall be as specified elsewhere in the Contract Documents. c) The air void system in hardened concrete when tested according to ASTM C 457 shall be: i. Air Content: 3.0% minimum ii. Spacing Factor: mm maximum d) Rapid chloride permeability of high performance concrete at 28 days shall be equal to or less than 1000 coulombs. e) Slag aggregate shall not be used. f) Superplasticizer may be added to the mix at the time of batching Bearing Strips The bearing strips used to support the precast panels shall be compressible, durable and designed to stay in place. Bearing strips shall be elastomeric, according to the requirements of OPSS Miscellaneous Steel Miscellaneous structural steel elements used with members and are to be left in place shall be hot-dipped galvanized according to CAN/CSA G164-M91 and meet the requirements of CSA G40.21 Grade 350W. 6.0 EQUIPMENT 6.01 Pretensioning Pretensioning equipment shall be according to CSA A CONSTRUCTION 7.01 Fabrication of Stay-in-Place Deck Panels June 2010 Pg. 4 of 10 SSP999S28

5 Plant Certification Stay-in-place deck panels shall be fabricated by a plant certified according to CAN/CSA A23.4 in the appropriate category Construction Requirements Panels shall be cast flat. Strands or reinforcing steel bars shall be continuous across the top of the members or projecting beyond the end of the panel and lapped. Sufficient support chairs shall be provided such that the strands and/or reinforcing steel bars are not vertically displaced between chair support locations. Chairs shall be durable and made of a non-ferrous metal or plastic. Panel lengths in the completed structure shall be as shown on the Contract Drawings. Initial panels lengths as cast, shall include an allowance for reduction in length due to elastic shortening caused by prestressing as well as creep and shrinkage effects prior to placing the cast-in-place topping Surface Finish The top surface of all panels shall have a rough surface, with vertical indentations of 3 mm amplitude spaced at 15 mm Curing Top surface curing compounds shall not be used. The panels shall be cured according to OPSS Storage Deck panels shall be stored for a minimum length of time after casting. Panels that have lengths less than 2500 mm shall be at least 15 days old before installation. Panels with lengths equal to or greater than 2500 mm shall be at least 30 days old prior to installation. Precast panels shall be kept in a horizontal position during storage, transportation and at the site Erection Panels shall not be lifted by attaching lifting devices to any strand or reinforcing steel bar projecting beyond the edges of the panel. Leakage shall be kept to a minimum. No leakage shall be permitted to fall onto the roadway below or into environmentally sensitive waterways Tolerances for Panels Precast panels shall meet the following tolerances: a) Panel lengths: ± 5 mm b) Panel widths: ± 10 mm June 2010 Pg. 5 of 10 SSP999S28

6 c) The maximum difference in plan view diagonal dimensions (squareness) of rectangular panels: Not greater than 3.5 mm per metre of diagonal length d) Thickness of panel: +5 mm, -3 mm e) For prestressed panels, strands shall be located at the mid-depth of the panel with a vertical tolerance of +0 mm, -3 mm, measured from the soffit, and a horizontal tolerance of ± 10 mm. f) Deviation from straightness of panel edges along the transverse joint between adjacent panels shall not exceed 1.5 mm per metre length (panels with greater deviation will be rejected). g) Vertical bowing of panels out of plane, after casting and immediately prior to erection, shall not be greater than the panel length /360, the panel width/360, or 10 mm maximum Quality Control Sampling and Testing Slump, Air and Temperature The Contractor shall be responsible for all aspects of sampling and testing the plastic concrete for slump, air content and temperature according to OPSS 1350 and the results of these tests recorded. The minimum frequency of testing shall be at least once for every 7 m 3 of concrete or each truck load of concrete Compressive Strength General The Contractor shall be responsible for all aspects of preparation, storage and transportation of cylinders to determine compressive strength. Moulds for all specimens shall be supplied by the Contractor and shall be made of plastic according to CAN/CSA A23.2-1D, with a lid. The lids shall be chemically and physically compatible with the concrete and shall provide a watertight seal for the moulds. The compressive strength of normal concrete shall be determined from 150 mm x 300 mm cylinders, with one set consisting of two cylinders. The compressive strength of high performance concrete and concrete with strengths greater then 50 MPa shall be determined from 100 mm x 200 mm cylinders, with one set consisting of three cylinders Transfer Strength Cylinders for the determination of transfer strength shall be cured under the same conditions as the concrete in the panels. The cylinders shall be tested at the Precaster s plant laboratory; otherwise it will be tested at an external CSA certified laboratory. The prestressing force shall not be transferred to the panels until two consecutive compressive strength results for normal concrete or three consecutive strength results for high performance concrete are greater than or equal to the specified transfer strength. It is the Contractor s responsibility to cast sufficient cylinders for determination of transfer strength. June 2010 Pg. 6 of 10 SSP999S28

7 Day Compressive Strength The Contractor shall cast one (1) set of cylinders for each lot to determine the compressive strength at 28 days. When the specified compressive strength is reached earlier, the lot shall be considered to have met the compressive strength requirements of this Special Provision. The cylinders shall be cured according to the requirements of OPSS Concrete cylinders shall be transported and delivered according to CAN/CSA A23.2-3C. The forms, on which the field data for the cylinders is recorded, shall be submitted to the laboratory with the concrete cylinders. A compressive strength result shall be the average of two cylinders for normal concrete and the average of three cylinders for high performance concrete Air in Hardened Concrete For evaluation of air void system parameters, the Contractor shall cast cylinders and shall test the cylinders according to ASTM C 457, except that a magnification of 100 to 125 shall be used. Testing shall be carried out by a Laboratory and operator(s) which are on the Ministry s list of qualified laboratories and operators for this test. One set of cylinders shall be cast for each lot according to CAN/CSA A23.2. The set shall consist of two 100 mm x 200 mm cylinders. The cylinders shall be cured under the same environmental conditions as the concrete in the members. Immediately following completion of curing of the members, the cylinders shall be transported to the testing laboratory. Cylinders shall be cut lengthwise into two halves, with one half to be tested by the Contractor and the other forwarded to the Ministry (Head, Concrete Section, Building C, Room 15, Wilson Avenue, Downsview, Ontario, M3M 1J8) within two weeks of casting the cylinders. Both cylinder halves shall be marked with a unique identification number. The portion forwarded to the Ministry shall have an information sheet securely attached to it detailing the contract number; lot number and Form A of the Concrete mix design for the component. Air void cylinder samples shall be retained by the Contractor until expiry of the one year general warranty, as defined elsewhere in the Contract Documents and shall be provided to the Contract Administrator upon request Rapid Chloride Permeability for High Performance Concrete For evaluation of rapid chloride permeability for high performance concrete, the Contractor shall cast and test cylinders according to ASTM C1202. Testing shall be carried out by a laboratory, which is on the Ministry s list of qualified laboratories for this test. One (1) set of cylinders shall be cast for each lot. Each set shall consist of two (2) 100 mm x 200 mm cylinders. The cylinders shall be cast from concrete sampled at the time the members are being manufactured and made according to CSA A23.2. Immediately following casting, the cylinders shall be stored at a temperature of 20 ± 5 C and shall be covered to prevent evaporation of water according to CAN/CSA A23.2-3C. The specimens shall be transported to the testing laboratory within 20 ± 4 hours of having been cast, then demoulded and stored at 23 ± 2 C in a moist condition until time of testing. A 10 mm thick slice shall be cut June 2010 Pg. 7 of 10 SSP999S28

8 off from the top of each cylinder before test specimens are cut from it. Two 50 mm long samples shall be cut from each cylinder and tested when the concrete is 28 to 32 days of age. Rapid chloride permeability cylinder samples and laboratory worksheets shall be retained by the Contractor until expiry of the one year general warranty, as defined elsewhere in the Contract Documents and shall be provided to the Contract Administrator upon request Defects and Deficiencies General The Contractor shall notify the Contract Administrator in writing immediately if any defects are present in the work, with an explanation of the cause and extent. Repairable defects shall be repaired at the Contractor s expense. The Contractor shall not proceed with the cast-in-place slab until the Contract Administrator has accepted all remedial work. Defects and deficiencies are classified as follows: a) Defects and deficiencies causing rejection b) Defects and deficiencies repairable by standard methods c) All other defects and deficiencies Defects and Deficiencies Causing Rejection A panel having any one of the following defects or deficiencies will be rejected: a) Panels not meeting the requirements of this Special Provision. b) Panels with honeycombing, voids, cavities, spalls and delaminations when the depth exceeds 45 mm or when the area of the defect exceeds 300 mm x 300 mm. c) Panels with cracks located parallel to or over the strands or reinforcing steel. d) Panels with cracks at the edges and /or with cracks at the bottom. e) Panels with cracks that are deeper than 25 mm and/or wider than 0.5 mm Defects and Deficiencies Repairable by Standard Methods A panel having one or more of the defects or deficiencies identified below shall be repaired according to the method specified: a) Panels with honeycombing, voids, cavities, spalls and delaminations when the depth does not exceed 45 mm or when the area of the defect is less than 300 mm x 300 mm shall be repaired as follows: i. Square all sides of the repair area. ii. Sawcut perimeter of removal area to a depth of 10 mm or to the depth of reinforcing steel or strands, whichever is less. iii. Remove all loose concrete using a chipping hammer or hand tools. June 2010 Pg. 8 of 10 SSP999S28

9 iv. Insert corrosion resistant wires and anchors. v. Abrasive blast clean all concrete surfaces to be patched according to OPSS 929. vi. Remove all dust and loose material from the prepared surface by using compressed air. vii. Moisten area to be repaired viii. Fill repair area with concrete or a proprietary patching material acceptable to the Owner. ix. Cure concrete according to OPSS 904 or cure proprietary patching material according to the manufacturer s recommendations. b) Panels with cracks other than those specified under defects and deficiencies causing rejection shall be repaired by epoxy injection according to OPSS 932. A proposal for the remedial work for the above defects shall be submitted to the Contract Administrator for review. The Contractor shall not proceed with repairs until approval of the proposal has been received All other Defects and Deficiencies For panels with defects or deficiencies not identified as rejectable or repairable by standard methods, the Contractor shall submit a proposal for repair to the Contract Administrator (CA) for review. The CA shall respond to the Contractor within seven Business Days of receipt of the complete repair proposal. If the Owner deems the repair proposal acceptable, the panel(s) shall be repaired according to the proposal. The Contractor shall not carry out any repairs without the acceptance of the proposal by the Contract Administrator. If the Owner deems the repair proposal unacceptable, the panels(s) shall be rejected and shall not be incorporated into the work. The repair proposal, signed and sealed by an Engineer, shall include as a minimum: a) Description of the panel. b) Assessment of any impact of the repaired defect(s) on durability, structural adequacy and integrity of the panel or on the structure. c) A detailed repair plan including materials, method and equipment to be used. d) Verification that the repair plan complies with the applicable standards for the type of work. e) All relevant supporting information, including material test results, field measurements and observations, production records, photographs, and structural analysis calculations, used for determining that the performance and function originally expected from the member will be met. f) Cause(s) of the defect and corrective action to be taken to prevent recurrence of the defect in future production, delivery or erection. The repair proposal for panels containing defects shall also include detailed sketches, width, length, depths, location and nature and frequency of any defects. 8.0 QUALITY ASSURANCE 8.01 Steel Reinforcement June 2010 Pg. 9 of 10 SSP999S28

10 The sampling and testing of steel reinforcement will be according to OPSS 905 and the Quality Control requirements of this Special Provision Acceptance The acceptance of the panels will be according to the Contract Documents including satisfactory completion of all repairs if applicable. Only panels meeting the requirements of the Contract Documents shall be incorporated into the Work BASIS OF PAYMENT Precast Panel Stay-in-place Deck Forms - Fabrication - Item Precast Panel Stay-in-place Deck Forms - Delivery - Item Precast Panel Stay-in-place Deck Forms - Erection - Item Payment at the Contract price for the above tender item(s) shall be full compensation for all labour, Equipment, and Material to do the work. June 2010 Pg. 10 of 10 SSP999S28