03300 Cast-In-Place Concrete (2)

SECTION 03300CAST-IN-PLACE CONCRETE

PART 1 GENERAL...................................................................................................................1

1.1 SCOPE..............................................................................................................................................11.2 REFERENCES.................................................................................................................................11.3 DEFINITIONS..................................................................................................................................21.4 TESTS...............................................................................................................................................21.5 CONCRETE CRACK CONTROLS.................................................................................................21.6 SUBMITTALS.................................................................................................................................31.7 QUALITY ASSURANCE................................................................................................................71.8 DELIVERY, STORAGE, AND HANDLING.................................................................................81.9 CONCRETE AND TOPPING CONTROL REQUIREMENTS......................................................9

PART 2 PRODUCTS..............................................................................................................11

2.1 MATERIALS..................................................................................................................................112.2 CONCRETE MIXES......................................................................................................................122.3 CONSTRUCTION JOINTS...........................................................................................................172.4 ABRASION RESISTANT BONDED CONCRETE FLOOR TOPPING......................................17

PART 3 EXECUTION............................................................................................................18

3.1 PREPARATION.............................................................................................................................183.2 PLACING CONCRETE.................................................................................................................183.3 CURING.........................................................................................................................................213.4 COLD WEATHER CONCRETE...................................................................................................223.5 REPAIR OF TEMPERATURE AND SHRINKAGE INDUCED CRACKS................................233.6 CONCRETE REPAIRING AND FINISHING...............................................................................233.7 CONCRETE FLOOR FINISHES...................................................................................................243.8 CONCRETE BONDING................................................................................................................253.9 TRAPROCK CONCRETE OVERLAYS.......................................................................................253.10 ABRASION RESISTANT BONDED CONCRETE FLOOR TOPPING......................................283.11 FIELD QUALITY CONTROL.......................................................................................................28

i

SECTION 03300CAST-IN-PLACE CONCRETE

PART 1 GENERAL

1.1 SCOPE

.1 The section specifies requirements for the supply of all labor, materials and equipment to complete concrete work as indicated on the Contract Drawings, specified herein and as required to complete the work.

.2 Except where noted otherwise in this specification, comply with Division 1 – General Requirements and all other Specification Divisions.

.3 Do not use materials that are toxic in installed condition. Do not use volatile organic compounds where not permitted by law. Where use of volatile organic compounds is permitted, provide adequate ventilation and take necessary safety precautions.

.4 Section Includes

.1 Normal-density concrete.

.2 Abrasion resistant bonded concrete floor toppings.

.3 Repair of cracks and damage that develop in concrete.

1.2 REFERENCES

.1 CSA A23.1 [-04] Concrete Materials and Methods of Concrete Construction.

.2 CSA A23.2 [-04] Methods of Test for Concrete.

.3 CSA A3001-03 Cementitious Materials for Use in Concrete

.4 CSA A3002-03 Masonry and Mortar Cement

.5 CSA A3003-03 Chemical Test Methods for Cementitious Materials for Use in Concrete and Masonry

.6 CSA A3004-03 Physical Test Methods for Cementitious Materials for Use in Concrete and Masonry

.7 CSA A3005-03 Test Equipment and Materials for Cementitious Materials for Use in Concrete and Masonry

.8 ACI 304.2R[-96] Placing Concrete by Pumping Methods.

CITY OF TORONTOSCARBOROUGH TRANSFER STATIONSURGE PIT SLAB REHABILITATIONCONTRACT NO. 14FS-33SWNOVEMBER 2014

03300–1CAST-IN-PLACE CONCRETE

.9 ASTM C260[-95] Specifications for Air-Entraining Admixtures for Concrete.

.10 ASTM C494[-92] Specification for Chemical Admixtures for Concrete.

.11 ASTM C900[-94] Test Method for Pullout Strength of Hardened Concrete.

.12 ASTM C1017[-92] Specification for Chemical Admixtures for Use in Producing Flowing Concrete.

.13 ASTM C1074[-93e1] Practice for Estimating Concrete Strength by the Maturity Method.

.14 ASTM C109/C109M [-11a] Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens).

1.3 DEFINITIONS

.1 Exposed Concrete: Concrete surfaces that can be seen inside or outside of structures regardless whether concrete is above water, dry at all times, or can be seen when structure is drained.

.2 Defective Areas: Surface defects that include honeycomb, rock pockets, indentations greater than 5 mm; cracks 0.25 mm wide and larger in non-liquid holding and containment structures spalls, chips, air bubbles greater than 20 mm in diameter, pinholes, bug holes, embedded debris, lift lines, sand lines, bleed lines, leakage from form joints, fins and other projections, form pop outs, texture irregularities, and stains and other color variations that cannot be removed by cleaning.

.3 New Concrete: Less than 60 days old.

1.4 TESTS

.1 In accordance with CSA-A23.2-04.

1.5 CONCRETE CRACK CONTROLS

.1 Place concrete in accordance with the crack control provision of CSA A23. In addition, take preventive and protective measures in proportioning, placing and curing the concrete to minimize shrinkage cracks. Such measures shall include:

.1 Do not place concrete against any surface that is less than 7C in temperature.

.2 Restrict the concrete temperature at delivery to the forms to a maximum of 25C.



.3 Wet down the work area, including formwork and abutting existing concrete prior to placing the concrete.

.4 Restrict pour lengths in the plan of walls to no more than 15 m. Allow a minimum of four days to elapse before placing adjacent sections. Detail the horizontal rebar to avoid continuity of the same day staggered pours.

.5 The Engineer may direct the Contractor to employ any of the means for crack control during hot weather outlined in the ACI Report and CSA standards “Hot Weather Concreting”.

1.6 SUBMITTALS

.1 Product Data Sheets

.1 Submit the manufacturer’s product data sheets including installation, application, and maintenance instructions for:

.1 Chemical admixtures.

.2 Air-entraining admixtures.

.3 Superplasticizing admixtures.

.4 Bonding agent.

.5 Repair materials.

.6 Abrasion Resistant bonded concrete floor toppings.

.2 Drying Shrinkage Test

.1 Drying Shrinkage Tests:

.1 Perform laboratory trial mixes of concrete used on project. Make two sets of three specimens for each shrinkage test.

.2 Prism Specimen Size: 100 mm by 100 mm by approximately 280 mm with effective gauge length of 250 mm.

.3 Specimens: Fabricate, cure, dry and measure as specified in ASTM C157 modified as follows:

.1 Remove specimens from molds aged 23 hours, ±one hour after trial batching.

.2 Place immediately in water at 22.8 C ±2°C for at least 30 minutes.



.3 Measure within 30 minutes thereafter to determine original length and then submerge in saturated limewater at 22.8°C, ±2°C.

.4 Measure specimens at age seven days to determine expansion expressed as percentage of original length. Length at age seven days shall be base length for drying shrinkage calculations (0 days drying age).

.5 Store specimens immediately in humidity control room maintained at 22.8 C, ±2°C and 50 percent, ±4 percent relative humidity for remainder of test.

.6 Measure to determine shrinkage expressed as percentage of base length and report separately for 7, 14, 21, and 28 days of drying after seven days of moist curing.

.4 Computing Drying Shrinkage Deformation: Deformation of Each Specimen:

.1 Difference between base length (at 0 days-drying age) and length after drying at each test age.

.2 Compute average drying shrinkage deformation to nearest 0.001 percent at each test age.

.3 If drying shrinkage of any specimen departs from average of that test age by more than 0.004 percent, disregard results obtained from that specimen.

.2 Concrete Shrinkage at 28-Day Drying Age: 0.040 percent maximum for laboratory trial mixes of proposed concrete for construction. If shrinkage specimen tests for concrete exceed shrinkage limits modify concrete mix to reduce shrinkage.

.3 Concrete Mix Design

.1 Submit the proposed concrete mixes, aggregate grading curves, and the supplier’s applicable standard deviations at least two weeks prior to any concrete placement.

.2 Indicate contents of the cement, cementitious hydraulic slag, coarse and fine aggregate, water, water reducing and air entrainment agents, and other admixtures, air content, slump, and locations of use for each mix.



.3 Submit detailed plan for cold weather curing and protection of concrete placed and cured in weather below 5ºC.

.4 Submit detailed plan for hot weather placements including curing and protection for concrete placed in ambient temperatures over 25ºC.

.5 Concrete mix designs will be reviewed for conformance with requirements of the Specifications and will be returned with Engineer’s comments.

.4 Source Quality Control Submittals

.1 Provide certification that source for fine, coarse and trap rock aggregates are not subject to deleterious expansion.

.2 Chemical admixtures, used in the production of concrete for potable water structures, shall be certified as safe product from recognized approving authorities

.3 Submit certification that the cement and supplementary cementing materials do not contain regulated metals and no hazardous waste derived fuels were used in the production of the cement(s).

.5 Quality Control Submittals

.1 Submit Concrete quality control plan for the project. Provide the following:

.1 Certification from concrete producer that a Professional Engineer has designed the mix based on the requirements of the Specification and that concrete mix will meet the performance requirements.

.2 Identify the Company and contact names of subcontractors, material suppliers and testing companies involved with concrete manufacture and placement.

.3 Identify concrete requirements for each element of the project.

.4 Identify all tests that will be used for material acceptance and indicate minimum specification requirements for each test.

.5 Identify the frequency of testing for each test.

.6 Identify the course of action to be taken if the testing program indicates that specification requirements have not been met.

.7 Concrete quality control plan shall not take precedence over any other Contract documents.



.8 Concrete finishers: Skilled personnel with a minimum of five years proven satisfactory experience finishing concrete of comparable size and scope.

.9 Engage manufacturers' representative for fulltime onsite supervision prior to, during, and after applications. Verify that specified products are correctly applied; amount and finishing procedures comply with manufacturer's printed instructions for project.

.2 Submit concrete delivery records.

.3 Submit a correlation curve of pullout strength test to standard cylinder strength test. Submit a correlation curve of strength of concrete at given time in hours to 28-day strength.

.6 Abrasion Resistant Bonded Concrete Floor Topping

.1 Submit the manufacturer’s data sheets and the manufacturer’s written instructions for storage and handling of materials, mixing, placement, finishing, curing, sealing, substrate surface preparation, bonding, joints, edges and environmental controls during all stages of the work for the floor topping.

.7 Concrete and topping Placing Schedule

.1 Submit a detailed concrete and topping placing schedule, including mix by type and location of proposed pour or application.

.2 Provide notice of intent to pour or apply topping between 24 hours and 7 days prior to the pour or application.

.3 Provide a completed Concrete Pour Release Form (appended) prior to each pour.

.4 Do not order concrete until the Concrete Pour Release Form has been signed by the Engineer.

.8 Certificates

.1 Submit certificate of Ready Mixed Concrete Production Facilities.

.2 Submit certification that aggregates will not, nor have the potential to, react with cement to result in deleterious expansion in the concrete.

.3 Submit certification that deleterious substances in aggregate are within limits specified in CSA A23.1-04, Table 12 - Limits for Deleterious Substances and Physical Properties of Aggregates.



.4 Submit certification that proposed performance mix will produce concrete meeting the requirements of Specifications.

.5 Submit certification that proposed mix design strengths have been selected allowing for the supplier’s standard deviations as indicated in CSA A23.1[-04], Clause 4.4.6 - Compressive Strength.

.6 Submit certification that bonding agent, if used, will meet the requirements of Specifications.

.7 Submit certification that crack injection materials are suitable for continuous submersion.

1.7 QUALITY ASSURANCE

.1 Ready Mixed Concrete Producer: Certified member in good standing of the local Ready Mixed Concrete Association.

.2 Concrete finishers: Skilled personnel with a minimum of five years proven satisfactory experience finishing concrete of comparable size and scope.

.3 Engage manufacturers' representative for fulltime onsite supervision prior to, during, and after applications. Verify that specified products are correctly applied; amount and finishing procedures comply with manufacturer's printed instructions for project.

.4 Installation of new toppings shall be in accordance with the manufacturer’s recommendations and requirements.

.5 Installation of new toppings is to be witnessed and approved by the manufacturer’s representative.

.6 Installation of topping systems must be by a contractor who is a current member of the Concrete Floor Contractors Association of Ontario.

.7 Concrete Testing

.1 Testing of concrete for materials and compression will be done by agencies paid for by the Owner.

.2 Pay for additional testing required because of changes in material or the mix proportions, as well as any extra testing of concrete or materials occasioned by their failure to meet the specification requirements.



.3 The use of testing services does not relieve the Contractor of his responsibility to provide materials and construction in compliance with the Drawings and Specifications.

.8 Pre-placement Meeting

.1 Hold a meeting at least four weeks prior to the initial placement of concrete to review the detailed requirements for preparing the concrete design mixes, finishes, and procedures for concrete placement for the structures.

.2 Arrange for the attendance at the meeting of the Engineer, Owner, and of concrete subcontractors, manufacturers, and suppliers including, but not limited, to the following:

.1 Contractor’s superintendent.

.2 Ready-mix concrete producer.

.3 Admixture manufacturer(s).

.4 Concrete pumping and conveying equipment supplier.

.5 Concrete formwork and finishing subcontractors.

.6 Topping material manufacturer and installer.

.3 Notify the Engineer at least 10 working days prior to the scheduled date of the meeting.

.4 The Engineer will set an agenda for the meeting at least five working days prior to the scheduled date of the meeting.

.9 Abrasion Resistant Bonded Concrete Floor Topping

.1 Use only sub-trades approved in writing by the product manufacturer who have at least 5 years’ experience in projects of similar type and size.

.2 The Contractor shall retain and pay for a full time representative from the product manufacture to inspect the work on site, and issue daily and final conformance reports for the installation.

.3 The Contractor shall provide a 2-year warranty for the installation of the abrasion resistant bonded concrete topping.

1.8 DELIVERY, STORAGE, AND HANDLING

.1 Comply with manufacturers’ recommendations for delivery, storage, and handling.



.2 Store materials in a manner that will prevent deterioration or contamination. Deteriorated or contaminated materials will be rejected and must be removed from site.

1.9 CONCRETE AND TOPPING CONTROL REQUIREMENTS

.1 Cold Weather Control Requirements

.1 The following requirements are in addition to CSA A23.1-04, Clause 7.4.2.5 - Cold-Weather Protection.

.2 Provide temperature-controlled enclosures for areas where concrete is placed whenever ambient air temperature is 5°C or lower.

.3 Protect concrete from the adverse effects of space-heated enclosures including local overheating and combustion products.

.4 Heat mix-water and, if necessary, aggregates when air temperature is at or below, or predicted to go below, 5°C at any time during the next 24 hours.

.5 Maintain temperature of reinforcing bars and forms above 10°C prior to placing concrete.

.6 Maintain temperature of concrete when deposited in forms not less than 15°C and higher than 25°C.

.7 Maintain temperature of concrete at surfaces at least 10°C for a minimum period of five days after placing and achieving minimum 75% of specified strength. Concrete temperature may then be lowered to ambient air temperature at a rate of 1/2°C per hour or 10°C per day

.8 Use additional protection if full 28-day compressive strength is required at an early age.

.9 Keep concrete continuously moist during the curing period. See section 03350 for details.

.10 The temperature difference for the concrete is being placed and the concrete being poured against is of primary importance during winter concreting. Therefore, the temperature of the surface of the previously poured concrete must be within 5°C of the concrete being placed but must not be lower than 7°C.

.2 High-Temperature Control Requirements

.1 The following requirements are in addition to CSA A23.1 -04, Clause 7.4.2.4 - Hot-Weather Protection.



.2 Limit peak temperature during the curing period to 40°C maximum. Placing temperature that will satisfy this requirement depends on ambient temperature, humidity at the time of placing, thickness of the concrete, and curing methods employed.

.3 Consider use of retarders, low-heat cement, slag replacement, ice in mixing water, pre-cooling of aggregates, cooling of concrete through continuous wet curing, and similar methods in order to prevent concrete temperatures from exceeding 40°C at any time.

.4 Monitor concrete temperatures for walls and slabs 500 mm or more in thickness. After concrete temperature has peaked, control rate of cooling to ambient air temperature at a rate of 1/2°C per hour to prevent cracking.

.5 Notwithstanding requirements of subparagraphs .1 and .2 above, do not place concrete with temperature higher than 25°C. Concrete with temperature in excess of 25°C on arrival at the site will be rejected. Remove rejected concrete from the site.

.3 Concrete and Topping Protection

.1 Protect freshly placed concrete and topping from damage due to construction operations and from cold, heat, rain, snow, running water, drying winds, and any other circumstances which would likely cause deterioration of concrete or topping quality.

.2 Use waterproof insulated covers or other suitable materials to enclose freshly placed concrete under these conditions.

.4 Frost Protection For Slabs On Grade (Not Applicable)

.1 Provide continuous protection for slabs on grade to prevent subgrade below from freezing during cold weather. Provide heated enclosures and insulation as required.

.2 Subgrade below completed tanks may be protected against frost by filling with water to a minimum depth of 2,000 mm. Place log booms, 200 mm diameter, at maximum spacing of 5,000 mm in each direction to abate ice pressures on tank walls. Break ice on formation.

.5 Influence of Ambient Concrete Temperature On Concrete Crack Control

.1 To minimize the formation of thermal cracks during placement and curing, maintain previously cured concrete and concrete that will be placed against it at the same temperature.



.2 Do not place concrete against any surface, which is less than 7C in temperature.

.3 The Engineer may direct the Contractor to employ any of the means for crack control during hot weather outlined in ACI Report “Hot Weather Concreting”, at no additional cost to the Contract.

.4 Failure to minimize temperature differential between adjacent pours will result in temperature induced cracking. Repair such cracks as specified in this Section.

.6 Service Loads Restrictions

.1 Verify that concrete in slabs, including slabs on grade, and support components have reached specified compressive strengths before subjecting slabs to service loads.

PART 2 PRODUCTS

2.1 MATERIALS

.1 Traprock

.1 Traprock shall be Aecon Marmora Quarry 13.2 mm concrete stone (DFC/HL1 CA) as supplied by Aecon Construction and Material Limited, 11 Indell Lane, Brampton, Ontario, L6T 3Y3, Tel: (905) 840-5914, Fax: (905) 840-7859.

.2 Cements

.1 Type MS “Moderate Sulphate Resistant” conforming to CSA A23.1/2.

.3 Supplementary Cementing Material

.1 Cementitious hydraulic slag: CSA A363-M “Cementitious Hydraulic Slag” and comply to the following conditions and requirements:

.1 For use with Type MS cement.

.4 Aggregates

.1 Normal-density Concrete

.1 Coarse aggregate: CSA A23.1; rough and angular gravel or crushed stone.

.2 Fine aggregate: CSA A23.1; natural sand.

.2 Traprock aggregate for Type B concrete.



.5 Admixtures

.1 Compatible with each other and with other concrete materials.

.2 Calcium chloride, thio-cyanates, or admixtures containing more than 0.05% chloride ions are not permitted.

.3 Corrosion inhibitor admixture shall be used only in the Disinfection Facility.

.4 Air-entraining admixture: ASTM C260; non-detergent type.

.5 Water-reducing admixtures: ASTM C494; Type A.

.6 Set-retarding admixture: ASTM C494; Type B.

.7 Superplasticizing admixture: ASTM C494; Type F 1or G 2 [ASTM C1017, Type 1 or 2.]

.8 Corrosion inhibitor: ASTM C494; Type C; DCI by:

.1 W.R. Grace Co. of Canada Ltd.

.2 Rheocrete CNI by Master Builders Technologies, Ltd.

.9 Corrosion inhibitor dosage: 10 L/m3

.6 Water: CSA A23.1; clear and free from oil, acid, alkali, organic matter, or other deleterious substances with a maximum soluble chloride ion content of 0.10% by weight.

.7 Bonding agent: Suitable for conditions of service and performance requirements of this Section.

.8 Epoxy Grout: Hydrocote 3061-I by BASF or approved equivalent.

.9 Polyurethane injection resin for sealing cracks, single-component Diphenylmethane Diisocyanate (MDI) based, water-activated, hydrophobic type resin:

.1 Flexible Resin by Multiurethanes Limited

.2 Hydro Active Flex LV by DeNeef Construction Chemicals (U.S.) Inc.

2.2 CONCRETE MIXES

.1 General



.1 Establish proportions of cementing materials, aggregates, water, and admixtures required to produce consistent workable concrete that is watertight, durable concrete with strength and other properties specified. Comply with clause 4.3.6-CSA A23.1-04 Volume Stability Considerations.

.2 Use same type and brand of cement throughout.

.3 Place no concrete whose mix design has not been reviewed by the Engineer.

.4 Provide the concrete with a consistency so that the concrete can be placed satisfactorily in the forms, but the mixture shall not be so wet as to segregate during placing.

.5 In no case will it be permitted to exceed the slumps specified without the written permission of the Engineer.

.6 For the type of cementing material, use a blend of Type MS Portland Cement and cementitious hydraulic slag to a minimum of 75% Type MS Portland Cement by weight of total cementing materials content.

.7 Three test cylinders for each Type of concrete will be taken from each day’s concreting or from every 100 m³ placed whichever is the greater. One of the cylinders will be tested at 7 days and the other two cylinders will be tested at 28 days.

.8 The cost of the concrete required for making the above test cylinders shall be borne by the Contractor.

.9 Comply with and allow for the supplier’s Standard Deviation as specified in CSA A23.1[-04], Clause 4.4.6 - Compressive Strength Requirements.

.10 Use high-slump concrete by addition of super plasticizing admixture for walls.

.11 The concrete for all slabs and walls shall be ‘low-shrinkage concrete’ as defined in clause 8.9 of CSA A23.1-04.

.12 Measure all aggregate by weighing. All measuring devices shall permit rapid adjustments of the mix.

.13 Source quality control

.1 Testing by an independent laboratory in accordance with CSA A23.1 and CSA A23.2, where test results less than one year are not available, to determine:

.1 Chemical composition and physical properties of aggregates.



.2 Presence and quantity of deleterious substances in aggregates.

.2 Description of location for Normal-density and Trap rock Concrete

.1 Type A: Concrete for suspended corridor slab containing reinforcing bars, unless specified otherwise.

.2 Type B: Concrete for floor and wall repairs and to build up the sloping floor and ramp, unless specified otherwise.

.3 Mixes for Concrete

.1 Select a mix complying with the table below and submit the complete details of sieve analyses of aggregates and proportions of all ingredients by weight to the Engineer for review.

.2 Base the tender price on providing concrete with cement, water content and strength as follows:

Type of Concrete

Required Minimum Compressive

Strength at 28 Days

Maximum Water-Cement

RatioSlump(mm)

Maximum Aggregate Size (mm)

A 35 MPa 0.45 75 25 20

B 35 MPa 0.45 100 25

12 (traprock)

.1 Cementing Materials Content

.1 Except where higher quantities are needed to meet strength or other requirements, provide the following minimum cementing materials contents.

.2 Type A: 320-330 kg/m3 minimum, for nominal 20 mm to 5 mm coarse aggregate.

.3 Type B: 320-330 kg/m3 minimum, for Trap rock aggregates nominal 12 mm coarse aggregates.

.2 Slump

.1 Provide slump consistent with placement, consolidation methods equipment and site conditions. Ensure concrete do not segregate during placement. Comply with CSA A23.1[-04].



.2 Maximum slump before addition of the super plasticizer: 25 to 50 mm .

.3 Maximum slump after addition of the super plasticizer: 150 mm. Super plasticizer , Master Builders Pozzolith 400N or approved equal.

.3 Air Content

.1 Comply with CSA A23.1[-04], Table 4 - Requirements for the Air Content Categories.

.2 Provide air content Category 2, unless noted otherwise.

.3 Provide air content Category 1 for loading bays, parking areas, and liquid holding structures.

.4 Provide 3% maximum air content for concrete forming floors where floor hardener is used.

.4 Admixtures

.1 All concrete shall contain an approved water reducing agent compatible with the plasticizer and conforming to ASTM C494, Type A.

.2 Use only approved admixtures as follows:

ConcreteGrade of Coarse Aggregate

Water Reducing Agent, ASTM C494, Type A

Air Entraining Agent

Entrained Air Content

A Maximum aggregate 20 mm

Yes Yes 5.0 1% (non-exposed concrete)6.0 2%(exposed concrete)

B Traprock aggregate 12 mm

Yes Yes 6.0 2%(exposed concrete)

.3 Provide an air entrainment agent conforming to CSA-23.1-04 compatible with the water reducing agent used.

.4 The admixtures shall be formulated by the manufacturer for the job area and weather conditions and shall be added to



the concrete in accordance with the manufacturer’s written recommendations.

.5 Except for the plasticizer, admixtures only are to be added at the plant in a liquid form.

.5 Use of Plasticizer

.1 Use of the plasticizer shall conform to CAN3-A266.6-M85 “Super-plasticizing Admixtures for Concrete”.

.2 The specified plasticizer shall be added to the concrete mix for every pour of Type A concrete.

.3 The manufacturer’s instructions shall be followed regarding the storage and handling of materials, dosages, mixing and the timing of the placement.

.4 The manufacturer’s representative shall attend the Site at the start of the concrete placement and provide the above-noted instructions. The representative shall be available throughout the course of the concrete work for further guidance and solution of problems that may arise during the use of the plasticizer.

.5 The approved plasticizer shall be added to the concrete mix on Site by a person knowledgeable, qualified, and experienced in the use of plasticizers.

.6 Complete and accurate records of all additions to the concrete mix shall be kept and submitted to the Engineer. Small amounts of plasticizer may be added at the plant with the written approval of the Engineer.

.4 Mix for Wall and Column Grout

.1 Grout shall be placed on all horizontal construction joints to a minimum thickness of 75 mm and shall have a mix design conforming to the following specifications:

.1 Minimum content of cementing materials: 600 kg/m³.

.2 Coarse aggregate: None.

.3 Fine aggregate: CSA A23.1; natural sand.

.4 Water/cementing materials ratio (W/C): 0.43 maximum.



.5 Slump: Matching Type A concrete.

.6 Air content: Matching Type A concrete.

.7 Admixtures: Use water-reducing admixture.

.8 Structural concrete mix containing super plasticizing admixtures can be used in lieu of wall and column grout provided approval is obtained from the Engineer.

.5 Mix for Pumped Concrete

.1 Comply with ACI 304.2R and this Specification.

.2 Fine aggregate with uniform grading curve and fineness modulus of 2.65 ±0.20.

.3 Use coarse aggregate with uniform grading curve.

.4 Super plasticizing admixture must be used for pumped concrete.

.5 Do not use admixtures, which promote bleeding.

.6 No Concrete Trucks or Concrete pumps are allowed on the surge pit slab.

2.3 CONSTRUCTION JOINTS

.1 Provide construction joints in the locations designated on the Drawings and where required for construction. Agree with the Engineer in writing before construction work is commenced, regarding the position of joints necessary for construction but not shown on the Drawings.

.2 Construct all joints in accordance with the details shown on the Drawings, true to line with sharp, unbroken edges.

.3 Install waterstops in all construction joints and/or joints subject to liquid pressure.

.4 Place grout on all horizontal construction joints to a thickness of 75 mm before placing the concrete.

2.4 ABRASION RESISTANT BONDED CONCRETE FLOOR TOPPING

.1 Acceptable Products:

.1 UCRETE IRON FILLED Placed on top of ANVIL-TOP 300 Topping systems by BASF



.2 STONCLAD UT Placed on top of EUCOFLOOR 404 with metallic aggregates Topping systems by EUCLID

.3 SIKAFLOOR 20 PURCEM Placed on top of EMERICRETE topping systems by SIKA

.2 Minimum total topping thickness: 25 mm; 12 mm (minimum) for top layer system and 13 mm (minimum) for lower layer system.

.3 Colour of each layer to be selected by the City.

PART 3 EXECUTION

3.1 PREPARATION

.1 General

.1 Determine requirements of other trades, inform concerned trades, and assume responsibility for location, installation, and quality of items, which affect the work of this Section.

.2 Preparation of Surfaces

.1 Remove water, laitance, curing compound, wood, and other debris from surfaces on or against which new concrete will be placed.

.2 Roughen and clean surfaces of previously placed concrete against which subsequent concrete will be placed.

3.2 PLACING CONCRETE

.1 General

.1 Do not commence concrete placing until sufficient manpower and equipment is available to complete the placement expeditiously preventing the formation of cold joints, and to produce specified surface finish.

.2 Provide standby equipment for critical items in case of equipment failure.

.3 Verify that cast-in-place accessories, inserts, and reinforcement are set correctly and are not disturbed during concrete placement.

.4 Place concrete on dry and clean substrate.

.5 Place concrete between expansion or construction joints in one continuous operation.



.6 Internal vibrators shall be of the high frequency type with 7000 minimum to 12000 maximum vibrations per minute when immersed in concrete.

.7 External vibrators shall have a minimum frequency of 36000 vibrations per minutes.

.8 Equipment made of aluminum material shall not come in contact with the concrete.

.9 The concrete pump shall be a reciprocating pump equipped to fit a pipeline at least 100 mm in diameter. The concrete pump and concrete trucks are not permitted on the surge pit floor slab.

.10 The mixer for the bonding agent shall be a stationary mixer, power driven, and capable of uniformly mixing the materials.

.11 Bull floats shall be commercially made of magnesium or wood.

.12 Straight edges shall be metal, 3,000 mm and 500 mm long and commercially made.

.2 Depositing

.1 Limit free drop of concrete to 1500 mm maximum in accordance with requirements of CSA A23.1[-04], Clause 7.2.4 - Depositing.

.3 Time Limitations on Concrete Placement

.1 Do not use concrete after a period of one and half hours (1.5hr) has passed since first mixing of ingredients.

.2 Do not use high-slump concrete after slump falls below 100 mm for non-flowing concrete and 125 mm for flowing concrete. Where permitted, retemper in accordance with manufacturer’s printed instructions. Monitor, and correct if required, air content of concrete that has been retempered.

.4 Adverse Weather Conditions

.1 Make suitable arrangements to prevent damage to fresh concrete, under adverse weather conditions.

.2 Do not allow rain, sleet, or snow to increase mixing water or damage surface finish.



.3 Plan placement frequency such that lift lines will not be visible in exposed concrete finishes.

.4 Provide windbreaks, shading, fog spraying, sprinkling, ice, wet cover, or other means as necessary to maintain concrete at or below specified temperature.

.5 Do not place concrete when ambient temperature is below 5ºC or approaching 5ºC and falling, without special protection.

.6 Do not place concrete against frozen earth or ice, or against forms and reinforcement with frost or ice present.

.7 Provide heated enclosures when air temperatures are below 5ºC.

.8 Maintain surface temperature of concrete above 5ºC.

.9 Provide maximum and minimum thermometers placed on concrete surfaces spaced throughout Work to allow monitoring of concrete surface temperatures representative of Work.

.10 External Heating Units:

.1 Vent heating units to atmosphere and do not locally heat or dry concrete. Where water cure is specified, maintain wet condition.

.2 Do not exhaust heater flue gases, directly into enclosed area.

.5 Wall and Column Grout

.1 Deposit 75 mm of wall and column grout evenly along horizontal construction joints in bottom of form through an elephant trunk immediately before placing wall or column concrete.

.6 Time Interval between Concrete Placements

.1 Construction Joints: Seven days wet cure continuously.

.2 Control Joints: Six days.

.3 Expansion Joints/Contraction Joints: One day.

.4 Wait at least two hours after depositing concrete in long columns and walls thicker than 200 mm before depositing concrete in beams, girders, or slabs supported thereon.

.5 For columns and walls 3 m in height or less, wait at least 45 minutes prior to depositing concrete in beams, girders, brackets, column capitals, or slabs supported thereon



.6 Walls and columns may be placed on slabs and vice versa as soon as initial placing has sufficient strength but not sooner than 12 hours.

.7 Consolidation

.1 Consolidate the concrete during and immediately after depositing, thoroughly and uniformly by means of tamping, hand tools, finishing machines, and vibrators in order to obtain dense, watertight, homogeneous concrete well bonded to reinforcing bars.

.2 Carefully vibrate concrete around the conduits, waterstops, and gas-stops to make sure thorough contact.

.3 Bend edge of horizontal waterstops , slightly upward allowing concrete to flow under and completely fill space below the waterstop . Verify no air is trapped below waterstop and concrete is in contact with waterstop over its entire surface area.

.4 Provide sufficient windows in forms or limit form height to allow for concrete placement through windows and for visual observation of concrete.

.5 Vibration consolidation not to exceed distance of 1 m from point of placement.

.8 Maximum Size of Concrete Placements:

.1 Limit size of each placement to allow for strength gain and volume change due to shrinkage

.2 Consider beams, girders, brackets, column capitals, and haunches as part of floor or roof system and place monolithically with floor or roof system.

.3 Should placement sequence result in cold joint located below finished water surface, install water stop in joint.

3.3 CURING

.1 Concrete curing shall be carried out immediately after finishing of the concrete surface a in accordance with CSA A23.1 and shall be maintained for a period of seven (7) days. Rate of evaporation is depend on relative humidity, concrete temperature and winds velocity; for rate of evaporation of moisture from concrete surface covered with water see CSA A23.1 appendix D.

.2 Cure the exposed fresh concrete by covering the surface with two layers of wet burlap. On top of the wet burlap shall be plastic (polyethylene) sheets to ensure that the burlap remains wet. Strips of burlap shall overlap by at least 150 mm. New burlap shall be thoroughly soaked for 24 hours before use.



.3 The plastic sheets shall be not less than 0.10 mm (4 mils) thick, and shall be standard commercial quality, free from snags, tears or any other visible flaws, providing a tough, pliable moisture - barrier. The plastic sheets shall be lapped a minimum of 150 mm and shall be securely held in place against displacement by wind or other means. Protect concrete against vibration and loading, as far as practical, and restrict all construction traffic, until the seven day strength has been achieved.

.4 The burlap for curing shall conform to OPSS 1306. Moisture vapour barrier shall be white, opaque, polyethylene film, at least 100mm thick conforming to OPSS 1305.

.5 The Contractor shall ensure that the burlap is maintained in a wet condition throughout the entire seven-day curing period.

.6 Cover newly poured slabs with burlap as soon as they can be walked on and keep them continuously wet with water for seven days.

.7 Loosen the formwork for walls and columns and saturate the concrete within the first 24 hours after placing.

.8 After stripping the wall forms apply a non-toxic curing compound meeting the requirements of ASTM C309. Apply the curing compound at the thickness recommended by the manufacturer after a minimum of 24 hours of moist curing. If a curing compound is not applied, continue moist curing for an additional five days.

3.4 COLD WEATHER CONCRETE

.1 In cold weather conform to the cold weather concrete provisions of CSA-A23-04, except where modified by these Specifications.

.2 The methods of protecting the concrete are to be approved by the Engineer and will be such as to prevent local drying. Open flame heaters will not be permitted.

.3 Provide suitable holes through the forms and in the concrete for the purpose of placing thermometers to determine the adequacy of heating and protection.

.4 The addition of chemicals to the concrete to prevent freezing will not be permitted.

.5 Provide in the tender price for all costs incurred in heating forms, aggregates, water, etc. during winter construction and in protecting all concrete from damage by the elements at all times.



3.5 REPAIR OF TEMPERATURE AND SHRINKAGE INDUCED CRACKS

.1 Propose the method of any repair to the Engineer for approval.

.2 Repair any cracks in the completed structures employing a suitable polyurethane injection technique to make sure cracks are completely watertight after repair.

.3 Remove surface injection materials following completion of the work and finish affected areas to match the surrounding concrete.

.4 Remove and replace honeycomb or embedded debris in concrete as directed.

.5 Patch existing concrete surfaces where damaged by cutting or drilling.

.6 Any surface that needs patching up has to be inspected and approved by the Engineer before the patching work commences.

.7 Cost of all repair work to be borne by the Contractor.

3.6 CONCRETE REPAIRING AND FINISHING

.1 As soon as the face forms are removed, repair and finish the surfaces of all concrete as set out below:

.1 Repairing

.1 Cut back the metal form ties not less than 25 mm from the surface. Fill the holes with non-shrinking grout, In-Pakt as supplied by C.C. Chemicals Ltd., and then finish as specified below.

.2 Cut honeycomb and other defective areas at right angles and at least 25 mm deep.

.3 Saturate all areas to be patched with water.

.4 Fill saturated areas immediately with mortar having the same general composition as the mortar in the concrete.

.5 After completely filling the cavities, finish the concrete to match adjacent surfaces.

.2 Finishing

.1 Concrete Finish S1 (Exterior surface below finish grade)

.1 Remove all ties, bolts, nails and other metal to a depth of 25 mm and fill the holes. Chip off and rub all fins and other projections until flush with the general surface.



.2 Concrete Finish S2 (General concrete finish)

.1 Provide the concrete finish S1 plus fill with mortar all air-voids larger than 5 mm in any direction.

.3 Concrete Finish S3 (Sack-rubbed Finish)

.1 Provide the concrete finish S2 plus apply sack-rubbed finish for interior walls available for viewing.

.2 Colour match repairs on exposed surfaces by adding white Portland Cement to the mix used for patching.

.3 Where honeycombing requires repairs deeper than 50 mm use In-Pakt grout for repair and stop 15 mm back from the finished wall surface. Use Portland Cement Mortar to fill the final surface and rub the whole area with a carborundum brick.

3.7 CONCRETE FLOOR FINISHES

.1 Finish the top or final surface of all concrete by one or more of the operations of screeding, floating, trowelling, or grinding as specified by the Engineer. Dusting of the wearing surfaces with dry materials to absorb moisture or to stiffen the mix will not be permitted. Strike off floor slabs true to the required level of slopes shown on the Drawings.

.2 Protect the floor finishes from damage after placing by laying protective timbers over the areas and keeping traffic to a minimum. Should the floor be damaged, the Engineer may require the damaged portions to be cut out and replaced with a separate hardened floor finish, at no extra cost to the City.

.3 Wood Float Finish: Screed and finish with a wood float all earth-covered slabs, all walkways, and where specified. Do not start floating until some stiffening has taken place in the concrete surface.

.4 Steel Trowel Finish: Screed all floors unless otherwise specified, then finish with a wood float to present a reasonably true uniform surface and then further finish with a steel trowel.

.5 Non Slip Finish: After initial finishing, floating, and first trowelling provide nonslip surface finish by swirl-trowelling the surface in accordance with CSA A23.1[-04], Clause 7.5.6.1 - Nonslip Surfaces. Provide nonslip swirl-trowel finish for surfaces like platforms, walkway slabs, loading docks, stairs, and other areas to receive shake applied surface hardener.

.6 Broom Finish: After initial finishing, floating, and first trowelling, provide nonslip surface finish by brooming the surface in accordance with CSA A23.1[-04], Clause 7.5.6.1 - Nonslip Surfaces with application of steel or fibre brooms at



least 450 mm. Pull broom gently over the surface from side to side at right angles to direction of traffic, with adjacent strokes slightly overlapping. Produce a broom finish surface free from porous spots, irregularities, depressions, or rough spots with uniform corrugations less than 3 mm.

3.8 CONCRETE BONDING

.1 Horizontal Construction Joints in Reinforced Concrete Walls:

.1 Thoroughly clean and saturate surface of joint with water.

.2 Limit wall and column grout placement to 50 mm maximum thickness, 25 mm minimum thickness.

.3 Do not deposit grout from pump hoses or large concrete buckets, unless specified placement thickness can be maintained and verified through inspection windows close to joint.

.4 Limit concrete placed immediately on top of slurry concrete to 300 mm thick. Thoroughly vibrate to mix concrete and grout together.

.2 To Existing Concrete:

.1 Thoroughly clean and mechanically roughen existing concrete surfaces to roughness profile of 10 mm.

.2 Saturate surface with water for 24 hours prior to placing new concrete.

3.9 TRAPROCK CONCRETE OVERLAYS

.1 Cement-sand bonding agent shall consist of Portland Cement and sand in the ratio of 1:1 by volume, mixed with sufficient water to form a stiff mixture. The consistency of the mixture shall be such that it can be applied with a stiff brush to the existing concrete in a thin even coating that will not run or puddle.

.2 Excess materials resulting from the performance of the work under this specification shall be removed and managed as specified in the Contract.

.3 The Project Manager shall be notified of the intent to place the overlay one working day prior to the commencement of the placement of the overlay. The work shall not proceed until the surface preparation has been inspected by the Project Manager.

.4 Only the finishing machine and buggies used to place concrete shall be allowed on the abrasive blast cleaned portion of the floor.



.5 Areas of reinforcing steel and concrete prepared for concrete overlay shall be protected at all times during placing operations from the dropping of the bonding agent or concrete from placing equipment or other sources, except at the intended point of discharge. Any such material shall be immediately removed.

.6 Equipment transporting concrete and runways used by equipment transporting concrete shall not be supported by floor reinforcing steel.

.7 Placement of concrete shall not begin until the trial run procedure as specified is complete and permission to place concrete has been given in writing by the Project Manager. In the case of unexpected interruptions during placing operations, a construction joint shall be formed by either chopping or saw cutting, at the direction of the Project Manager, and all new concrete shall be covered with polyethylene film. Portions of the concrete overlay with incomplete or unsatisfactory consolidation or finishing shall be removed.

.8 Overlay concrete shall not be placed when the air or floor temperature is below 10°C or likely to fall below 10°C, or is above 30°C or likely to rise above 30°C during the duration of the placing operations.

.9 Longitudinal construction joints will be permitted only where shown in the Contract.

.10 Concrete shall not be placed adjacent to longitudinal joints in concrete overlay less than 36 hours old. At temperatures less than 10°C the Project Manager may extend this time requirement.

.11 Neither construction traffic nor operation traffic shall be permitted on the finished surface of the overlay concrete until the curing period has elapsed.

.12 Prior to seasonal shutdown, operations shall be scheduled in such a manner to ensure that the overlay is placed in all areas where concrete removal has commenced.

.13 Immediately prior to wetting the floor surface, all dust and loose material shall be removed from the prepared surface of the existing floor concrete by compressed air.

.14 The floor surface shall be maintained in a wet condition for a period of one hour before the application of the bonding agent. Excess water shall be removed from the surface using compressed air, immediately prior to application of the bonding agent.

.15 A thin coating of the bonding agent, cement-sand for concrete, shall be brushed into the prepared surface. All vertical and horizontal surfaces against which the overlay will be placed shall receive a thorough even coating with no excess of bonding agent in any areas. Excess fine aggregate separated from the bonding



agent mixture after application shall be removed from the floor surface. The rate of application of the bonding agent shall be such that the brushed material does not become dry before it is covered with overlay. At no time shall the bonding agent be placed more than 2m in front of the overlay placement. Bonding agent not used within 30 minutes after mixing shall not be used.

.16 The overlay shall be placed on the floor and struck off slightly above final grade using concrete rakes.

.17 In the event of an interruption in the placing of the overlay, the exposed edge of the overlay shall immediately be covered with wet burlap. If the delay in placing exceeds 10 minutes, the bonding agent already applied to the floor shall be removed.

.18 When undue delays occur, all overlay material ahead of the floor finishing machine shall be removed and a joint formed.

.19 The overall combination of labour and equipment for proportioning, mixing, placing and finishing the overlay shall be capable of finishing a minimum of 4 m3 of overlay per hour, and shall be so arranged that not more than 20 minutes elapses between discharge of the overlay from the mixer and the final finishing.

.20 Debonded and honeycombed areas shall be removed and replaced. Cracks shall be repaired.

.21 The overlay shall be mechanically consolidated by the finishing machine and struck off to the final grade. The surface finish shall be free from open tears, plucked aggregates, and local projections. Areas adjacent to the wall which cannot be machine finished and areas not meeting the surface finish requirements shall be finished with hand finishing equipment.

.22 The use of water or other material to aid in finishing will not be permitted.

.23 The inability to produce a uniform, closed surface to the overlay shall be cause for rejection of the overlay in the affected area. Overlay so rejected shall be removed and new overlay placed using methods approved by the Project Manager.

.24 Except across the crown, the surface of the overlay after finishing and before any required texturing shall be such that when tested with a 3m long straight edge placed anywhere in any direction on the surface, there shall be no gap greater than 6mm between the bottom of the straight edge and the surface of the concrete. Where the gap exceeds 6 mm, the overlay shall be either removed and new overlay placed, or the overlay shall be refinished so that the requirement for surface tolerance is satisfied.

.25 Two layers of wet burlap that have been presoaked by immersion in water for a period of 24 hour immediately prior to placement shall be placed on the concrete



overlay within 2 to 4m from the finishing operation. Strips shall overlap 150mm and shall be held down without marring the surface of the concrete. The burlap shall be covered with a layer of moisture vapour barrier as soon as the moisture vapour barrier can be applied without deforming the surface of the concrete. The moisture vapour barrier shall be lapped a minimum of 150mm. Air flow in the space between the moisture vapour barrier and the burlap shall be prevented by holding the moisture vapour barrier down at the edges and all laps. The burlap shall be kept continuously wet during the curing period.

.26 Except as specified for saw cutting construction joints in overlays labour and equipment shall not be allowed on the overlay for 12 hours after placement. The surface shall receive a wet burlap cure for not less than 96 hours.

3.10 ABRASION RESISTANT BONDED CONCRETE FLOOR TOPPING

.1 The manufacturer’s written instructions shall be followed regarding the storage and handling of materials, mixing, placement, finishing curing and sealing of the floor topping.

.2 The manufacturer’s written instructions shall be followed for the substrate surface preparation, bonding, joints and edges.

.3 The manufacturer’s written instructions shall be followed for environmental controls during all stages of surface preparation, installation finishing and curing.

.4 All work shall be completed in strict accordance to the manufacturer’s full time site representative instructions.

.5 Finish the topping to a medium steel trowel finish.

.6 To prevent surface cracking, cure the floor topping as soon as possible with a curing compound, approved in writing by the topping product manufacturer.

.7 After the preparation of the surfaces, The topping systems shall be used to build up the floor to its final elevations and contours.

3.11 FIELD QUALITY CONTROL

.1 General

.1 Tests will be made throughout progress of the Work and will be paid for by the Owner to determine concrete quality. Tests will be in accordance with CSA A23.1 and CSA A23.2. Provide labour, concrete, and other facilities for making the test specimens.



.2 Provide and maintain facilities for storing and initial curing of test cylinders, and provide suitable crates for shipping test cylinders in accordance with CSA A23.2[-04], Test Method A23.2-3C - Making and Curing Concrete Compression and Flexural Test Specimens.

.3 The testing laboratory shall provide the test results to the Owner, Engineer, Contractor and material supplier within 5 days of availability. For test that fails to meet the Specification inform Engineer, Contractor and material supplier within 48 hours.

.2 Standard Strength Tests

.1 Provide concrete for one standard strength test consisting of three cylinders for each 100 m³ of concrete of each type placed in any day. If the amount placed, for each type of concrete is less than 100 m³ in a day, provide concrete for one standard strength test. One cylinder will be tested at 7 days and two at 28 days.

.3 Linear Shrinkage Tests

.1 Provide linear shrinkage tests for every 1000 m3 of concrete used on the project to ensure conformity to approved mix designs.

.2 Provide linear shrinkage tests for any pour greater than 150 m3.

.4 Concrete Temperature Monitoring

.1 Provide and keep in working order sufficient Taylor Instrument pocket biotherm thermometers model 6097-1 to monitor concrete temperatures in each pour.

.2 Install 12 mm diameter by 150 mm deep copper tubes crimped at bottom end into concrete at each monitoring location. Fill tube with water.

.3 Monitor concrete temperature at corners and in the centre of each concrete placement.

.5 Air Content Tests

.1 Testing agency will carry out air content tests in accordance with CSA A23.1 and CSA A23.2.

.6 Slump Tests

.1 Testing agency will carry out slump tests in accordance with CSA A23.1 and CSA A23.2.



.7 Failure to Meet Strength, Air Content, or Slump Requirements

.1 When measured slump or air content falls outside of required limits, carry out a check test immediately on another portion of the same sample. In the event of a second failure, the concrete will be considered to have failed to meet the requirements. Remove the whole batch, from which the samples were taken, off the site.

.2 When the strength requirement provisions are not met, carry out one or more of the alternatives of CSA A23.1[-04], Clause 4.4.6.8 - Failure of Standard Cured Cylinder Test Results to Meet Requirements.

.3 When, after carrying out these requirements, there is still doubt about of the adequacy of the concrete, strengthen or replace, as directed, portions of the Work which failed to develop the required strength.

.8 Uniformity of Mixed Concrete

.1 If the results of slump, air content or density for any mix design do not comply with CSA A23.1[-04], Table 13 - Determination of Within-Batch Uniformity, alter mixing operations and equipment until tests indicate that the requirements are satisfied.

.9 Concrete Delivery Records

.1 Submit with each batch of concrete before unloading, a typed delivery ticket prepared at the ready mix plant containing following information:

.1 Name of ready-mix batch plant.

.2 Serial number of ticket.

.3 Date and truck number.

.4 Name of the Contractor.

.5 Name of Job.

.6 Specified 28-day strength of concrete with identifying mix number.

.7 Time loaded or of first mixing of cement and aggregates.

.8 Temperature of Fresh Concrete

.10 Keep records of the time when each load arrives at the site and when discharge is completed.



END OF SECTION





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03300 Cast-In-Place Concrete (2)

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