Division 03 - Concrete Section New Westminister Multi-Use Civic Facility & Office Building Project No Page 1

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1 Project No Page 1 PART 1 GENERAL 1.1 Documents.1 The General Conditions of the Canadian Standard Construction Document CCDC-2, together with all amendments and supplements and Division 1 General Instructions, bound herewith, are to be considered a part of this Section and are to be complied with, as applicable, in carrying out the Work of this Section. 1.2 Description.1 Section Includes.1 The Work described under this Section includes the supply and installation of the following, as indicated on the drawings and as specified therein. These specifications shall form part of and be read in conjunction with the structural notes contained in the drawings..2 The Work on this Section includes the furnishing of all labour, materials, equipment and all else necessary to complete the cast-in-place concrete work..1 Concrete in structure as indicated on the structural drawings, and architectural concrete as indicated on the architectural drawings..2 Provision of waterseals and waterstops as required by the Consultant..3 Setting of anchor bolts and steel anchor plates for steel work complete with pockets as called for on the drawings..4 Supply and installation of vapour barrier under slabs on grade..5 Provision of all keys and dowels in construction joints..6 Supply and application of curing compounds, sealers and hardeners..7 Architectural concrete including, but not limited to sidewalks, topping, curbs, etc..8 Installation of prefabricated inserts provided by others..9 Section Concrete Testing.3 Related Work Under Other Sections:.1 Section Green Building Information Submittal Forms

2 Project No Page 2.2 Section LEED Requirements and Procedures.3 Section Concrete Formwork.4 Section Concrete Reinforcement.5 Section Cast in Place Concrete Parking Decks (Reinforced).6 Section Architectural Concrete.7 Section Post Tensioned Concrete Unbonded 1.3 LEED Certification Requirements.1 This Project has been registered under LEED Canada CS 2009 with a goal of LEED Gold. Refer to Section LEED Requirements and Procedures, the LEED Rating System, and the LEED Canada Reference Guide for Core & Shell Development In order to achieve LEED Gold Certification for the Project, the Contractor and all Subcontractors, suppliers and manufacturers shall comply with all requirements as specified in LEED Requirements and Procedures, and they shall be fully aware of all required laws and available strategies to achieve the maximum credits, including any applicable exemplary performance levels, for the following:.1 Erosion and Sedimentation Control..2 Construction Waste Management / Product Waste Recyclability..3 Recycled Content..4 Local and Regional Materials..5 Certified Wood..6 Construction Indoor Air Quality (IAQ) management..7 VOC/Low-Emitting Materials Compliance..3 This Project has an appointed Project LEED Consultant who shall provide the overall strategies for the LEED certification program. All queries regarding all general LEED activities, document submissions, site procedures and proposed strategies pertaining to the achievement of LEED certification should be directed to the Project LEED Consultant..4 The Contractor shall immediately appoint a Contractor LEED Coordinator to oversee all daily on-site activities and submission procedures and documentation pertaining to the LEED certification program. The Contractor LEED

3 Project No Page 3 Coordinator shall liaise directly with, and provide up-to-date monthly progress reports at month end to, the Project LEED Consultant throughout the Project..5 After award of contract, each Subcontractor shall immediately appoint a Subcontractor LEED Coordinator to liaise with the Contractor LEED Coordinator throughout the Project..6 After award of contract, Subcontractors shall attend a LEED orientation meeting with their selected Subcontractor LEED Coordinator, in accordance with Section LEED Requirements and Procedures..7 After award of contract, all Subcontractors shall submit to the Contractor LEED Coordinator all LEED Submittals Checklists, including all information, data and MSDS on materials and products included in their bid with respect to recycled content, regional materials, and indoor air quality in accordance with Section LEED Requirements and Procedures..8 The Contractor LEED Coordinator must confirm that the Subcontractor s submissions are complete and verified prior to the Subcontractor s first progress draw application, and any subsequent progress draws, as required..9 Refer to Section Waste Management and Disposal for product waste recyclability requirements..10 The project scorecard outlines targeted credit thresholds. Please note that the scorecard is subject to change throughout project development and construction, and will be updated as necessary. Updates will be communicated by the Project LEED Consultant to the Contractor LEED Coordinator, and the Contractor LEED Coordinator will ensure all Subcontractors and other related parties are also immediately aware of the updates. 1.4 Standards.1 Unless otherwise specified, concrete, concrete materials reinforcement and methods of construction shall conform to the requirements of CAN3-A23.1 and CAN3-A23.2. Copy of these standards shall be obtained by the Contractor and kept at the job site..2 The requirements of this Section shall be considered as supplemental to the above standards. 1.5 Regulations and Codes.1 Comply with the provisions of local building ordinances, bylaws and regulations of authorities having jurisdiction. Furnish such notification and reports and pay all fees to these authorities as required.

4 Project No Page Testing.1 The Owner will pay for an independent testing laboratory. The testing agency shall review and approve concrete mixes prior to commencing construction. The testing agency shall have full authority in regard to acceptance or rejection of concrete delivered to the site. The testing agency shall reject all non-conforming concrete and notify the Engineer immediately by telephone of any low-strength test results..1 Prepare and test concrete cylinders for compressive strength..2 Establish slump and percentage of entrained air..3 Perform tensile and bending tests on reinforcing steel as required by the Engineer..4 Submit copies of the test results directly to the Owner, Consultant, Engineer and Contractor..5 Should work not meet specifications, all subsequent testing costs will be charged to the Contractor..2 Testing procedures for concrete shall conform to the following requirements:.1 Compressive tests on concrete shall be carried out in accordance with CSA standard A23.1, except that a strength test shall consist of seven (7) days and the remaining two at an age of twenty-eight (28) days for control of design strength of concrete..2 Slump and air entrainment test shall be conducted at the time of sampling concrete for compressive tests and shall be conducted in conformity with CSA Standard A Frequency of testing to comply with CSA Can 3, A23.1, Section Testing procedures for reinforcing steel shall comply with requirements of CSA Standard G30.12 which shall form the basis of acceptance or rejection..4 Provide at no additional cost to the Owner:.1 Samples of all material required for testing..2 Cooperation in the execution of concrete testing which shall include protection against injury or loss of cylinders..3 Access to the Owner and his Representatives to test and/or inspect materials..4 Site storage facilities meeting the requirements of CSA Standard A23.2 for concrete test cylinders prior to removal to the laboratory.

5 Project No Page 5.5 The Contractor shall give the Engineer or his Authorized Representative at least twenty-four (24) hours notice for the inspection of the reinforcing. If the reinforcing or other subtrades affecting the concrete work are not complete and approved a further inspection will be made with twenty-four (24) hours notice of correction of defects. Concrete shall not be placed before the Engineer or his Authorized Representative has inspected and passed the reinforcement in place..6 Any concrete placed without approval from the Engineer shall be replaced at no cost to the Owner..7 Cost of second inspections will be to the Contractor s account..8 The Contractor shall cooperate fully with the testing laboratory, and shall give the Laboratory Consultant at least twenty-four (24) hours prior notice of a concrete placement. (In-site strengths of all post-tensioned slabs shall be verified prior to stressing using an approved testing system such as lok-test inserts.)* 1.7 Coordination.1 Cooperate with other trades to permit proper execution of the Work..2 Consult with other trades to ensure exact location and extent of items supplied and work required by other trades which are to be incorporated in the concrete work. 1.8 Product Delivery.1 Concrete shall be delivered from a plant approved by the Engineer. If there is any problem of delivery or quality control of the concrete, the Engineer shall have the right to require a change to another supplier. 1.9 Job Conditions.1 Meet the requirements of CAN3-A23.1, Clause 21, for protection including hot weather protection, cold weather protection and preparation and cooling after protection. Refer to Section Architectural Concrete..2 Meet requirements of CAN 3-A23.1, Clause 28, architectural concrete for exposed concrete Construction Joints.1 Construction joints shall comply with the requirements of CSA Standard A23.1, Clause Location of construction joints to be approved by the Engineer and shall be coordinated with reinforcing steel detailing.

6 Project No Page Submittals.1 Concrete Mixes.2 Formwork.1 Submit four (4) copies of all proposed concrete mixes to the Engineer for review before any concrete is delivered to the site..1 Design, engineering and construction of formwork and reshoring shall be the responsibility of the Contractor. Submit for review to the Engineer drawings of formwork and reshoring. PART 2 PRODUCTS 2.4 Materials.1 All concrete shall be supplied in accordance with CAN3-A23.1. The Contractor shall be responsible for the preparation of all mix designs in accordance with CAN 3-A23.1. Clause 14.8 Alternate 1 to provide the following properties unless otherwise noted:.1 Minimum 20 MPA strength at twenty-eight (28) days, higher where noted on the drawings;.2 Exposure Class C for exterior, Class D for interior concrete and Class A for parking slabs;.3 Nominal course aggregate size ¾ ;.4 Slump at discharge 3 ± ½ ;.5 Air content: see drawings, 5% ± 1% U/N except five percent (5%) to eight percent (8%) for Class A;.6 For concrete in floors of parking areas, minimum cement content shall be 320 kg/m. If pozzolanic material is used in the mix, then for purposes of this clause, 2 / 3 of the pozzolan by weight shall be considered as equivalent to cement..7 Water cement ratio shall be.45 maximum for all parking areas..2 Concrete Strengths.1 Refer to structural drawings..3 Mix Designs.1 Concrete mixes shall be propportioned by the supplier in accordance with CSA-A to meet the requirements herein and on the drawings. All

7 Project No Page 7 concrete shall be normal weight unless noted otherwise. The property requirements are as shown on the structural drawings and herein..2 The mix designs shall take advantage of Supplementary Cementing Materials (SCM s) such as fly ash, silica fume and blast furnace slag to reduce the cement content of the concrete to the maximum extent possible consistent with strength and durability requirements..3 Fly ash shall conform to the standard. The following information shall be submitted in a letter signed by the concrete supplier / manufacturer s designated professional engineer :.4 The reduction in Portland Cement from Base Mix to Actual SCM Mix (as a percentage) where base mix design is defined as 100 kg/m3 cement per 10 MPa for air entrained concrete and 100 kg/m3 per 12 MPa for nonair entrained concrete..5 The following cement reduction percentages by element shall be used as a guideline on this project, subject to approval by the Materials Consultant. As indicated in the table below, these targets can be reduced for cold weather placing. The percentage reductions in cement should be achieved without affecting the cost or schedule of the project. Element Winter Summer Footings 30% 40% Slab-on-grade 30% 35% Columns, Walls 35% 45% Suspended Slabs 30% 40% Toppings 15% 25% Mass Footings, Piers 50% 50%.6 The overall cement reduction (as defined by LEED Canada-NC 1.0 and in this specification) to be achieved for this project must average 35% (average of all concrete elements and including winter and summer pouring)..7 In order to take advantage of SCM s, 56 or 90 day strength testing may be acceptable for certain elements as indicated in item where the cement reduction percentages are greater than 30%..8 Concrete with high volumes of supplementary cementing materials shall comply wih CSA-A , clause 8.8.

8 Project No Page 8.9 All materials for concrete shall confirm to the requirements of CSA Standard A23.1. Calcium chloride or admixtures containing chlorides, fluorides or nitrates shal not be used..4 Curing Compounds.1 Where permitted or specified, shall be a liquid, membrane forming, curing compound containing a fugitive dye and meeting the requirements of ASTM C309, applied at the rate recommended by the Manufacturer. Sternson s Florseal or other preapproved types may be used..5 Non-Metallic Hardener.1 Where specified, shall be non-coloured, non-metallic; Sternson s Colorplete Natural or preapproved hardener..6 Form Release Agent.1 Shall be applied to all forms where the finished concrete surface is to be exposed. The release agent shall be non-staining and, where applicable, paintable. (Refer to Section ).7 Waterstops.1 To be Burke Vinylok RB PVC waterstop or preapproved equal..8 Form Accessories.1 To be partially or wholly embedded in the concrete, such as ties or hangers, shall be commercially manufactured type..9 Vapour Barrier: 6 mil polyethylene sheets. PART 3 EXECUTION 3.4 Tolerances.1 Variation from level or grade as indicated on the drawings for slab surfaces, beam soffits, lintels, sills, horizontal grooves, parapets and other conspicuous lines to be ¼ in 20-0 or 3 / 8 in any bay..2 Variation from plumb in surfaces of columns, walls, pilasters, beams, vertical joints or grooves, or other conspicuous lines to be ¼ in the greater of 10-0 or one storey height, and ½ in total height..3 Variation from cross-section dimension as indicated on the drawings of columns, beams, slabs, and walls to be minus ¼ to plus 3 / 8..4 Variation of building lines in plan and position of columns and walls to be ½ in any bay or 20-0 maximum. Surfaces adjacent property lines must not project

9 Project No Page 9 beyond property lines. Lines of vertical elements above and below any floor level shall align within ¼..5 Variation in steps of stairs to be 1 / 8 for risers and ¼ for treads, otherwise as indicated..6 In addition, tolerances for concrete work shall conform to CSA Standard A23.1, Clause Formwork.1 Formwork shall comply with the requirements of CSA Standard A23.1, Clause Refer to architectural drawings for location, details, and finishes for exposed concrete surfaces..3 Forms shall be treated with a non-staining concrete release agent which will permit the bonding of finishes to concrete surfaces..4 Be responsible for the forming and setting of slots, sleeves, bolts, hangers, inserts, conduit, etc and ensure these items are secure and not displaced during placing of concrete..5 Be responsible for the design and adequacy of all formwork..6 Form design and construction shall have sufficient strength and rigidity to produce a structure which is in line and in the proper position and shape, to the tolerances specified and be such that they will not leak mortar or result in visible irregularities in finished concrete..7 Forms and/or shoring removal times shall be reviewed with the Engineer the commencement of the project. Such review does not relieve the Contractor from his responsibility for the safety of the structure..8 Conduits, outlet boxes, etc are not to be located within columns or shear walls except as approved by the Engineer prior to construction..9 Conduits in slabs and walls are not to be larger than one third the slab or wall thickness and must be placed within the middle third at four (4) clear between. Installations in structural members must be approved by the Engineer prior to placing concrete..10 Dust and debris shall be removed from all formed areas. Holes in slabs, walls, etc are to be approved by the Engineer prior to construction..11 Major openings for mechanical and other services are shown on the structural drawings as an aid in planning construction only. Check all contract drawings, shop drawings and specifications in order to ensure that all provisions for openings, blockouts and chases are met during construction.

10 Project No Page Due care shall be taken to ensure the subsidence of the formwork due to sinking of sills, compression of supporting materials and the tightening of joints do not adversely affect any line or grade of the final concrete surface. 3.6 Placing of Concrete.1 Placing of concrete shall comply with CSA Standard A23.1, Clause Special provisions for shrinkage are required for walls longer than 25-0 cast monolithically. Refer to structural drawings for details..3 Unless specified by the Mix Designer, no concrete shall be placed later than thirty (30) minutes after leaving the transit mixer and no concrete shall be used from trucks more than ninety (90) minutes after leaving the mixing plant. Comply with CSA A The addition of water to the concrete after leaving the plant shall be done only upon authorization of the Mix Designer and Concrete Supplier. The addition of such water shall be noted on the delivery slip and reported to the testing agency. Comply with CSA A The placement of concrete shall be such that embedded materials, formwork or accessories are not damaged or displaced. 3.7 Reshoring.1 Procedures for reshoring concrete work shall be submitted to the Engineer for review prior to construction. Load in excess of the structure design loads indicated on the structural drawings shall be indicated and reviewed by the Structural Engineer. 3.8 Construction Joints.1 Joints not shown on the drawings shall be approved by the Consultant and Engineer and shall be made and located as to least impair the strength and appearance of the structure..2 A key shall be provided at all vertical construction joints. Horizontal joints shall be cleaned and roughened. Shearwall CJs shall be roughened to a full amplitude of ½ minimum..3 All reinforcing steel shall be continuous across joints unless otherwise noted..4 The surface of the concrete at all joints shall be thoroughly cleaned and all laitance removed..5 Provide waterstop as indicated at construction joints.

11 Project No Page Joint Fillers and Sealers.1 Provide joint fillers and sealers at the location and to the details shown on the drawings..2 Particular care shall be taken to construct clean joints free from any foreign material which will impair the proper function of the joint..3 Joint filler material shall be anchored to the previously poured concrete surface..4 Unless shown otherwise joint filler shall extend for the full depth of the joint and shall terminate 1 below the top of the joint. The 1 space shall be filled with joint sealer Patching.1 Immediately after the removal of forms, all bolts, ties, nails or other metal not specifically required for construction purposes shall be removed or cut back to a depth of 1 from the surface of the concrete..2 Structural repairs shall be accomplished under the direction and supervision of the Materials Consultant..3 All areas requiring patching shall be saturated with water. The surface shall be scrubbed with a neat cement paste and repaired by filling with cement mortar of the same general composition as that used in the concrete. The mortar shall be well pressed or packed into the depression so as to completely fill the cavity and then finished to match the adjacent surface..4 Areas which have been patched shall be cured in accordance with the requirements outlined elsewhere in this Section Finishing of Formed Surfaces.1 Surface finishing of formed surfaces shall be as specified under Section : Concrete Finishes Floor Finishing.1 Finishing of concrete slabs shall comply with CSA Standard A23.1, Clause 22 and with tolerances indicated for Type A and in accordance with Section : Concrete Finishes. Due care shall be taken to prevent excessive build-up in elevation of slab concrete at column locations..2 General.1 Sprinkling of dry cement or a mixture of dry cement and sand on the surface of fresh concrete to absorb water or to stiffen the mix shall not be permitted during any stage of floor construction.

12 Project No Page 12.3 When finishes are to be applied to a concrete floor slab, the surface finish of the slab shall meet the requirements of the Subtrade responsible for the applied floor finish..4 Do not continue to trowel a concrete slab which has been heavily rained upon Slab On Grade.1 Place slabs on grade on compacted granular fill..2 Provide 6 mil polyethylene vapour barrier under all interior slabs on grade..1 Lap side and end joints between lengths of membrane a minimum of 6. Overlap joints in direction in which concrete is placed..2 Except where keyed and doweled, extend membrane up edges to top of slab at junctions with vertical construction..3 Repair tears and holes in vapour barrier with self-adhesive vapour tape or with patches secured by tape..3 Provide 1 / 8 wide by 1¼ deep saw-cut strip control joints to pattern as indicated on the drawings and at intervals not exceeding Care should be taken that the control joints are made in a neat, accurate fashion. Waviness and inaccurate Work resulting in joints not intersecting in a proper fashion may result in remedial Work at the Contractor s expense Openings Through Structural Work.1 If, after any part of the structural Work has been completed, it is required that additional openings be made through the structure, the Engineer shall be so informed. No opening shall be made through completed Work without authorization in writing by the Engineer Rejection of Defective Work.1 In the event that concrete tests do not conform to the requirements of this specification, or when conditions are such to cause doubt about the safety of the structure, test any portion of the structure in accordance with CAN 3-A C. Such test shall be made at the expense of the Contractor..2 Where, in the opinion of the Engineer, material or workmanship fails to meet the requirements of the specification, such Work may be rejected. Work rejected shall be replaced or repaired to the approval of the Engineer and at no additional cost to the Owner..3 Acceptance criteria shall be 100% of the design strength of the concrete in situ. Alternative testing methods shall be evaluated by the Materials Consultant who

13 Project No Page 13 shall indicate anticipated twenty-eight (28) day and long term strength. The Engineer shall evaluate suitability of low concrete strength and indicate those which are not acceptable..1 If the Contractor is, in any way, dissatisfied with the decision of the Engineer, he shall, without delay, make his proposal for alternative rectification..4 Equipment Bases 3.16 Camber.1 Provide all concrete bases for mechanical and electrical equipment..1 The top surface of concrete elements shall be cambered to accommodate immediate and long term deflections due to self weight and applied loads. See structural drawings Inserts and Openings.1 Install all embedded steel connections, anchorages, inserts, anchor bolts, angles, sleeves, expansion joint covers, reglets and other embedded items shown or called for on the drawings, specified, shown or required for other sections..2 Install all blockouts and pockets shown or called for on the drawings General.1 The proposed mix designs shall be submitted for review and acceptance to a concrete testing laboratory certified to the CSA standard A as a Category 1 or Category 2 laboratory. End of Section