Canadian Standards in Building Codes

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CANADIAN STANDARDS

IN

BUILDING CODES

issued by the

ASSOCIATE COMMITTEE ON THE NATIONAL BUILDING CODE

NATIONAL RESEARCH COUNCIL OTTAWA, CANADA First Edition 1966 1 NRC No. 8993

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Prepared by the Codes Secretariat of the

Division of Building Research National Research Council

Ottawa Canada

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3

FOREWORD

This volume has been prepared and is now published by the Associate Committee on the National Building Code as a further service to all users of the National Building Code of Canada. It constitutes a companion volume to "AST.M Standards in Building Codes". This other volume of over 1400 pages is published by the American Society for Testing and Materials from its offices at 1916 Race Street, Philadelphia, Pennsylvania, 19103. The third edition of the ASTM volume was published in 1965 with a list price of $15.00, copies being available to ASTM members at $10.50. The two volumes combined contain the actual wording of all the principal standards mentioned in the National Building Code of Canada, 1965, with the exception of a small group of standards which, although of im-portance, are of such length that they have been only summarized in this book. The Associate Committee hopes that all users of the Code will have available these two supplementary volumes so that all questions about standards can be readily allswered by direct reference to the original documents.

This volume has been prepared with the cordial co-operation of the staff of the Canadian Standards Association in Ottawa and with the ap-proval of the Board of Directors of CSA. The Associate Committee records its appreciation for this assistance. It is hoped that the appearance of this volume will lead to a broader appreciation of the value of the documents published by CSA.

The volume contains in addition to its main content of CSA standards reproductions of standards and specifications published by the following organizations:

Canadian Government Specifications Board, Ottawa, Onto

American Concrete Institute, Detroit, .Mich., U.S.A. American Standards Association,

New York, N.Y., U.S.A. British Standards Institution,

London, \V.1, England.

All these organizations have also kindly assisted the Associate Committee by granting permission for this use of some of their documents. This assist-ance is also appreciated and the thanks of the Associate Committee are hereby recorded.

Close liaison will be maintained with ASTl\1 in the future development of these two companion volumes. Comments for the improvement of this volume will always be welcomed and should be addressed to the Secretary, Association Committee on the ~ational Building Code, c/o National Research Council, Ottawa.

Ottawa,Ont., September 1966 ROBERT F. LEGGET, Chairman.

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5

Page CONCRETE REINFORCEMENT STEEL

CSA G30.6-1954 Specifications for Reinforcing lVlaterials for Concrete Reinforcement. . . .. 325 G30.7-1961 Special Large Size Deformed Billet-Steel Bars for

Concrete. . . .. 329 G30.10-1964 Deformed Billet-Steel Bars for Concrete

Reinforce-ment with 60,000 psi l\1inimum Yield Point. . . .. 334 CODE FOR PIPING SYSTEMS

CGSB 24-GP-3 Identification and Classification of Piping Systems 623 COPPER AND COPPER BASE ALLOYS

CSA B125-1962 CSA B54.1-1960 B54.3-1964 B54.5-1963 BS 476-1963 CSA B44-1966* B51-1965 B52-1965* B72-1960* B139-1962 * B149-1966* C22.1-1966* CSA A82.21-1950 A82.25-1950 A82.32-1954 CSA B70-1963 CSA A31-1959 CSA A60.1-1962 CSA B137-1963 * Summary only.

PIPE AND TUBE

Plumbing Fittings. . . .. 289 FLASH TESTS

Determination of ~oncombustibility of Building l\1aterials. . . .. 255 Methods of Fire Tests of Walls, Partitions, Floors, Roofs, Ceilings, Columns, Beams, and Girders. . . . .. 263 Standard Methods of Fire Tests of \Vindow and Glass Block Assembly ... 276 Fire Test of Building l\1aterials and Structures. . . . .. 602

GENERAL SAFETY

Safety Code for Elevators, Dumbwaiters and Escalators ... 234 Code for the Construction and Inspection of Boilers and Pressure Vessels ... 235 Mechanical Refrigeration Code ... 254 Code for Installation af Lightning Rods. . . . . .. 288 Installation Code for Oil Burning Equipment ... " 321 Installation Code for Gas Burning Equipment. . . . .. 322 Canadian Electrical Code ... , ... 323

GYPSUM

Gypsum ... 176 Gypsum Partition Tile or Block. . . .. 178 Design Requirements for Reinforced Gypsum Con-crete. . . .. 182

IRON

Cast Iron Soil Pipe and Fittings ... 281 MODULAR COORDINATION

Code for Modular Coordination in Buildings ... 133 PIPE AND DRAIN TILE

Specifications for Vitrified Clay Pipe ... 141 PLASTIC PIPES

Polyethylene Pipe for Cold Water Services ... 308

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Page QUICKLIME

CSA A82.42-1950 Quicklime for Structural Purposes. . . . .. 186 A82.43-1950 Hydrated Lime for lVlasonry Purposes ... 189

SHEET AND STRIP STEEL

CSA G40.1-1959 General Requirement for Delivery of Rolled Steel Plates, Shapes, Sheet Piling, and Bars for Structural Use ... 342 G40.8-1960 Specifications for Structural Steel with Improved

Resistance of Brittle Fracture ... " 367 STEEL BOLTING AND RIVET MATERIAL

CSA G40.2-1959 Structural Rivet Steel. . . .. 365 ASA BI8.2.1-1965* Square and Hexagon Bolts and Screws ... 600 BI8.2.2-1965* Square and Hexagon Nuts ... 601

STRUCTURAL STEEL

CSA G40.12-1964 General Purpose Structural Steel. ... 372 S136-1963 Design of Light Gauge Steel Structural Members. '" 476

CSA 056-1962 CGSB 70-GP-l CSA 043-1953 0141-1965 0177-1965 TIMBER PILING

Round Timber Piles ... " 391 VAPOUR BARRIERS

Vapour Barriers; Sheet, for Use in Above-Grade Building Construction. . . .. 628

WOOD

Structural Timber ... 375 Softwood Lumber. . . .. ... 434 Qualification Code for Manufacturers of Structural Glued-Laminated Timber. . . .. . ... 457

WOOD PRESERVATION

CSA 080-1962 Specifications for \Vood Preservation ... 402 08Q-CI2-1962 Creosoted-Wood and Foundation Piles ... 409

WELDING

CSA W47-1947 Welding Qualification Code for Application to Fabricating and Contracting Firms .... , ... 524 W55.2-1957* Resistance Welding Practice. . . . .. 556 \V55.3-1965 Resistance \Velding Qualification Code for

Fabrica-tors of Structural Members Used in Buildings. . . .. 557 \V59-1946 Welding of Steel Structures (I\1etallic Electric-Arc

Process). . . .. 560 \V117-1952* Safety in Electric and Gas \Velding Cutting

Opera-tions ... 570 WELDING ELECTRODES

CSA \V48.1-1962* lVlild Steel Arc-Welding Electrodes ... 555

* Summary only.

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p

E

CONTENTS IN NUMERIC SEQUENCE

STANDARDS IN THE NATIONAL BUILDING CODE

Canadian Standards Association Standards

7

Page

CSA A5-1961 * Portland Cements. . . . .. . . .. . .. 10

A8-1956* Masonry Cement. . . .. 11

A23.1-1960 Code for Concrete .Materials and lVlethods of Con-crete Construction. . . 12

A23.2-1960 :Methods of Test for Concrete.... ... 60

A23.2.12-1960 Making and Curing Concrete Compression and Flexure-Test Specimens in Laboratory. . . .. 98

A23.2.13-1960 Compressive Strength of :Moulded Concrete Cy-linders. . . . .. 104

A23.2.14-1960 Making and Curing Concrete Compression and Flexure Test Specimens in the Field. . . .. 106

A23.2.16-1960 Securing, Preparing and Testing Specimens for Hardened Concrete for Compressive and Flexural Strengths. . . .. 113

A23.2.17-1960 Weight per Cubic Foot, Yield and Air Content of Concrete (Gravimetric) ... 116

A23.2.18-1960 Air Content (Volumetric) of Freshly lVlixed Concrete 119 A23.2.19-1960 Air Content of Freshly l\1ixed Concrete by Pressure lVlethod ... 122

A23.2.21-1960 Sampling Fresh Concrete ... , ... 132

A31-1959 Code for lVlodular Co-ordination in Buildings ... " 133 A60.1-1962 Vitrified Clay Pipe ... 141

A82.1--1965 Burned Clay Brick ... 151

A82.3-1954 Sand-Lime Building Brick ... 158

A82.4-1954 Structural Clay Load Bearing \Vall Tile ... 161

A82.5-1954 Structural Clay Non Load Bearing Tile .... , ... 166

A82.7-1954 Facing Brick (Made from Clay or Shale) . . . 170

A82.21-1950 Gypsum ... 176

A82.25-1950 Gypsum Partition Tile or Block. . . .. 178

A82.32-1954 Specification for Design Requirements for Reinforced Gypsum Concrete ... 182

A82.42-1950 Quicklime for Structural Purposes ... 186

A82.43-1950 Hydrated Lime for l\1asonry Purposes. . . .. 189

A82.56-1950 Aggregate for Masonry Mortar. . . .. 191

A 135-1962 Prestressed Concrete. . . .. 193

A165.1-1964 Hollow Load Bearing Concrete lVlasonry Units ... 216

A165.2-1964 Hollow Non Load Bearing Concrete l\1asonry Units 221 A165.3-1964 Solid Load Bearing Concrete lViasonry Units ... 225

AI65.4-1965 Concrete lVlasonry Units ... 230

B44-1966* Safety Code for Elevators, Dumbwaiters and Escalators ... 234

B51-1965 Code for the Construction and Inspection of Boilers and Pressure Vesse~ ... 235

* Summary only.

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B52-1965* B54.1-1960 B54.3-1964 B54.5-1963 B70-1963 B72-1960* B125-1962 B137-1963 B 139-1962* B149-1966* C22.1-1966* G30.6-1954 G30.7-1961 Page

Mechanical Refrigeration Code. . . .. 254

Determination of Noncombustibility of Building Materials. . . .. 255

Methods of Fire Test of \Valls, Partitions, Floors, Roofs, Ceilings, Columns, Beams and Girders. . . .. 263

Standard Methods of Fire Tests of \Vindow and Glass Block Assembly ... 276

Cast Iron Soil Pipe and Fittings ... 281

Code for Installation of Lightning Rods. . . .. 288

Plumbing Fittings ... " 289 Polyethylene Pipe for Cold Water Services ... 308

Installation Code for Oil Burning Equipment. . . .. 321

Installation Code for Gas Burning Equipment. . . . .. 322

Canadian Electrical Code. . . .. 323

Specifications for Minimum Requirements for the Deformations of Deformed Steel Bars or Concrete Reinforcement. . . . .. ... 325

Specifications for Special Large Steel Deformed Billet-Steel Bars for Concrete Reinforcement ... 329

G30.10-1964 Specifications for Deformed Billet-Steel Bars for G40.1-1959 G40.2-1959 G40.8-1960 Concrete Reinforcement with 60,000 psi Minimum Yield Point.. . . .. ... 334

General Requirements for Delivery of Rolled Steel Plates, Shapes, Sheet Piling, and Bars for Structural Use ... 342

Structural Rivet Steel. . . .. 365

Specifications for Structural Steel with Improved Resistance of Brittle Fracture ... 367

G40.12-1964 General Purpose Structural SteeL ... 372

043-1953 Structural Timber ... 375

056-1962 Round Timber Piles. . . .. 391

080-1962 Specification for Wood Preservation ... 402

080-C12-1962 Creosoted-\Vood and Foundation Piles ... 409

0141-1965 Softwood Lumber. ... 434

0177-1965 Qualification Code for Manufacturers of Structural S136-1963 S157-1962 W47-1947 Glued-Laminated Timber. . . .. 457

Design of Light Gauge Steel Structural Members. . .. 476

The Structural Use of Aluminum in Buildings. . . .. 500

\Velding Qualification Code for Application to Fabricating and ContI acting Firms ... " 524 \V48.1-1962* Mild Steel Arc Welding Electrodes ... 555

W55.2-1957* Resistance \Velding Practice ... " 556 W55.3-1965 Resistance Welding Qualification Code for Fabrica-W59-1946 tors of Structural Members Used in Buildings. . . .. 557

\Velding of Steel Structures (Metallic Electric-Arc Process) ... 560

\V117-1952* Safety in Electric and Gas \Velding Cutting Opera-tions ... 570 • Summary only.

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9 Page

American Concrete Institute Standards

ACI 214-1965** Recommended Practice for Evaluation of Compres-sion Test Results of Field Concrete ... 571

American Standards Association Standards

ASA B18.2.1-1965* Square and Hexagon Bolts and Screws ... 600 ASA B18.2.2-1965* Square and Hexagon Nuts. . . .. . ... 601

British Standards Institution Standards

BS 476, Part 1,1963** Fire Test of Building Materials and Structures. 602 BS 1207-1961 ** Hollow Glass Blocks ... 620

Canadian Government Specifications Board Standards

CGSB 24-GP-3, 1961 ** Code for Identification and Classification of

Piping Systems-Fire Protection Equipment ... 623 CGSB 70-GP-1, 1960** Vapour Barriers, Sheet for Use in Above-Grade

Building Construction. . . . .. 628

• Summary only .

•• Included in whole in this document by kind permission of the issuing agencies listed:

American Concrete Institute, Detroit, Michigan, U.S.A. British Standards Institution,

London, W. 1, England.

Canadian Government Specifications Board, Ottawa, Ontario.

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'/

10

CSA A5-1961

SPECIFICATION FOR

PORTLAND CEMENTS

This Standard covers the chemical and physical requirements, methods of sampling, chemical analysis, and physical testing of Portland cements including Normal, High Early Strength, and Sulphate-Resisting Types.

The chemical requirements include limits for loss on ignition, insoluble residue, sulphur trioxide, magnesium oxide, and tricalcium aluminate. The physical requirements set forth limits for fineness (200 mesh test), soundness (autoclave test), sulphate resistance (lean mortar bar test), time of setting (Vicat and Gillmore methods), and tensile strength (briquette test for 1, 3, 7 and 28 days).

Inspection and sampling requirements cover size of sample, sampling equipment and methods (automatic sampling devices, manual sampling of bulk cement, manual sampling of bagged cement), sampling interval (cement delivered to silos or boats, cement shipped by rail, cement shipped by truck and lot quantities in storage), treatment of sample, sieving, and compositing . . Methods for chemical analysis cover samples (procedure and contamina-tion), apparatus (balances, weights, and glassware), purity of reagents (water, chemicals), concentration of reagents (concentrated and dilute reagents, standard and non-standard solutions, and indicators), and test procedures (loss on ignition, insoluble residue, sulphur trioxide, tricalcium aluminate, ferric oxide, combined oxides of iron and aluminum, alumina, magnesia).

~Methods for physical tests cover general requirements (accuracy of

scales, weights and glass graduates, temperature and humidity and deter-mination of normal consistency), deterdeter-mination of fineness (standard sieves, manipulation and calculation), determination of soundness by autoclave expansion test (moulds, autoclave, length comparator, test procedure, and calculation), sulphate resistance (test pieces, moulds, measurement, propor-tions, mixing, moulding, handling, exposure, storage, length changes and expansion limit), determination of time of setting Vicat method (appara-tus, manipulation, time of setting), determination of time of setting Gillmore method (apparatus, manipulation and time of setting), and tensile strength (test pieces, moulds, standard sand, proportions, mixing, moulding, storage and testing).

The above is a summary of the CSA Specification noted. The full text of the Specification is available from:

Canadian Standards Association, 235 Alontreal Road, Ottawa 7, Ontario.

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4 CSA A8-1956

SPECIFICATION FOR

MASONRY CEMENT

11

This Standard covers cement prepared specifically for use in masonry mortars. It recognizes two types as follows: Type 'H' Masonry cement for general use in masonry construction; and Type "L" masonry cement for use in masonry construction where high strength mf)rtar is not required. Test requirements set forth limits for time of (Gillmore), com-pressive strength (7 days and 28 days), soundness, water retention, air content, absorption and staining test.

Inspection requirements cover facilities, sampling, and copies and certificates of tests.

An Appendix 'A' covering sampling methods for testing masonry cements includes test samples, direction of sampling, methods of sampling (automatic sampling devices, manual sampling of bulk cement), frequency of sampling (cement shipped by rail or truck, lot quantities in storage), and treatment of sample (containers, identification of containers and pretreat-ment of test samples).

An Appendix 'B' covering methods for physical testing of masonry cement includes general requirements (tests, accuracy of scales, weights, and graduates, and temperature and humidity), preparation of cement pastes (manipulation), determination or normal consistency (vicat appa-ratus, moulding test specimen, consistency determination, and calculation of water content), determination of soundness by autoclave expansion test (safety, moulds, autoclave, length comparator, manipulation of cement pastes, calculation of autoclave expansion, and re-testing), determination of time of setting (Gillmore needles, preparation of specimen, determination of time of setting), preparation of cement mortars (proportions by volume, blended sand, sieves, weight of cement, mixing water, mechanical mixing apparatus, temperature, mixing procedure, and suggested sequence of tests), determination of How of mortars, (flow table, How table mould, flow table caliper, tamper, and manipulation), determination of entrained air (general, measure, calibration of measure, capacity, weight per 400 millilitres, specific gravity of cement, standard liquids, procedure, calculation of specific gravity, reproducibility, and calculation of air content), determination of compressive strength (test specimens, moulds, preparation of cube moulds, moulding test specimens, storage of test specimens, testing machine, age of test, preparation of cubes, testing operations and calculation), water retention test (apparatus, procedure, and calculation), absorption test for water repellency (procedure and calculation), and staining test (general, preparation of sample, and methods of

The above is a summary of the CSA Specificatt'on noted. The full text of the Specification is available from:

Canadian Standards Association, 235 A10ntreal Road, Ottawa 7, Ontario.

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NOTE: The Association desires to call attention to the fact that this Standard is intended to include the technical provisions necessary for the supply of the material herein referred to, but does not comprise all the necessary provisions of a contract.

A23.1-1960

CODE FOR CONCRETE MATERIALS

AND

METHODS OF CONCRETE CONSTRUCTION

1. SCOPE

1.1 Scope.

This Code covers materials to be used and methods to be followed for the proportioning and manufacture of concrete, together with requirements for mixing, transporting, placing, forming, finishing, curing, and testing of concrete.

1.2 Special Methods and Systems.

Special methods and systems not covered by this Code may be used upon approval of the proper authority.

2. DEFINITIONS

2.1

The following definitions apply in this Code:

Admixture

means any material other than cement, water, fine aggregate, or coarse aggregate added to concrete at time of mixing;

Air-entrainin~

admixture

means a material which is used as an ingredient of concrete which is added to the batch immediately before or during its mixing for the purpose of entraining air;

Aggregate

means inert material which is mixed with cement and water to produce concrete;

Coarse

a~~regate means aggregate, subject to specified tolerances, retained on a No.4 sieve, and of a maximum size generally not larger than 4 inches;

Fine

ag~regate means aggregate, subject to specified tolerances, passing a No. 4 sieve;

Lightweight

aggre~ate means aggregate of special inert materials which produce concrete with a unit weight of less than 120 pounds per cubic foot;

Cement

means Normal Portland Cement, High Early Strength Port-land Cement, Sulphate-Resisting PortPort-land Cement or such other cement as may be permitted by the engineer. The Canadian bag of cement, when used as a unit of proportioning, shall be considered as 87Y2 pounds, unless otherwise specified;

Concrete

means a mixture of cement, water, fine and coarse aggregates, and admixtures if specified;

Consistency

means a general term used to designate the relative plasticity of freshly mixed concrete or mortar;

Engineer (or Architect)

means the engineer qualified and authorized to administer the requirements of this Code, or such person appointed and authorized in writing to do so by him;

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os

CSA STANDARD A23 13

Fineness modulus

means an empirical factor obtained by taking 1/100 of the sum of the cumulative percentages of a sample of aggregate retained on each of a specified series of sieves. The sieves used are Nos. 100, 50, 30, 16, 8, 4, %-inch, %:-inch, lY2-inch, and larger, increasing in the ratio of 2:1;

Laitance

means extremely fine material of little or no hardness which may collect on the surface of freshly deposited concrete or mortar, resulting from the use of excess mixing water, and usually recognized by its relatively light colour;

Mortar

means a mixture of cement, fine aggregate, and water;

Proportions

means the relative quantities of the ingredients which make up a concrete mix, usually measured by weight;

Surface moisture

means the water carried by the aggregate except that held by absorption within the aggregate particles themselves;

Water:cement ratio

means the ratio of the amount of water contained in a freshly mixed batch of concrete to the amount of cement contained in the same batch. The amount of water shall mean the total water added to the batch, plus any surface moisture carried by the aggregates.

3. CEMENT

3.1 Portland Cement.

Portland cement shall comply with the require-ments of the latest issue of CSA Standard AS, Portland Cerequire-ments.

4. AGGREGATES

4.1 General.

The quality and grading requirements of fine and coarse aggregate for use in all concrete, except lightweight concrete, shall meet the requirements of Clauses 4.2 to 4.5. Aggregate for lightweight concrete shall meet the requirements of Clause 4.6.

4.2 Separation of Aggregates.

Fine and coarse aggregates shall be kept separate, and recombined in proper proportions in the mixer.

4.3 Sampling

4.3.1 Methods.

Aggregates shall be sampled according to CSA Standard A23.2.1, Sampling Stone, Slag, Gravel, Sand, and Stone Block for use as Highway lVIaterials, and their properties shall be determined as required in the following Clauses.

4.3.2 Submission of Samples.

Representative samples of all aggre-gates proposed for use shall be submitted to the Engineer sufficiently in advance of the commencement of operations to permit carrying out the required tests.

4.4

Fine Aggregate

4.4.1

General Characteristics.

Fine aggregate shall consist of natural sand, manufactured sand, or an approved combination thereof.

4.4.2 Grading

4.4.2.1 Sieve Analysis.

Fine aggregate shall be graded within the limits specified in Table 1. Not more than 45 per cent shall be retained between any two consecutive sieves of those shown in TabJe 1. The method of determining gradation by sieve analysis shan be according to CSA Standard A23.2.2, Sieve Analysis of Fine and Coarse Aggregates.

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TABLE 1

GRADING LIMITS FOR FINE AGGREGATES

Sieve Size ?/g-inch No.4 No.8 No. 16 No. 30 010.50 No. 100

Total Passing Sieve Per Cent by Weight

100 95-100 80-100 50-85 25-60 10-30 2-10

4.4.2.2 Fineness Modulus.

The fineness modulus of fine aggre-gate shall be not less than 2.3 or more than 3.1.

4.4.2.3 Uniformity.

To control the grading of fine aggregate from anyone source, a preliminary sample, representative of the material which it is proposed to furnish, shall be submitted prior to actual deliveries. Any shipment of fine aggregate, made during the progress of the work, showing a variation in fineness modulus greater than

±

0.20 from that of the preliminary sample shall be rejected or, at the option of the Engineer, may be accepted subject to such changes in concrete proportions as he may consider necessary.

4.4.3 Deleterious Substances

4.4.3.1 Limits for Deleterious Substances.

The amounts of deleterious substances in fine aggregate, each determined on independent samples complying with the grading requirements of Table 1, shall not exceed the limits specified in Table 2. Determinations of deleterious sub-stances shall be made in accordance with the following CSA Standards:

(a) A23.2.3, Clay Lumps in Natural Aggregates; and (b) A23.2.4, Lightweight Pieces in Aggregate; and

(c) A23.2.S, Amount of l\1aterial Finer than No. 200 Sieve in Aggregate.

TABLE 2

LIMITS FOR DELETERIOUS SUBSTANCES IN FINE AGGREGATE

Substances Maximum Per Cent by Weight of Total Sample

Clay lumps 1.0

3.0 (a) Material finer than No. 200 Sieve

Oven-dry material, coarser than No. 50 Sieve, floating 011 a

liquid having a specific gravity of 2.0

Shale

0.5 (b) 1.5

NOTES: (a) In the case of manufactured sand, ~f the material finer than the No. 200 sieve consists of the dust of fracture, essentially free from clay or shale, this limit shall be 5 per cent.

(b) Does not apply to manufactured sand produced from blast furnace slag.

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CSA STANDARD A23 15

4.4.3.2 Or~anic Impurities

(a) Fine aggregate shall be free from injurious amounts of organic impurities.

(b) Except as provided in the following, aggregates subjected to the test for organic impurities given in CSA Standard A23.2. 7, Organic Impurities in Sands for Concrete, and producing a colour darker than the standard colour shall be rejected:

(i) A fine aggregate failing in the test may be used provided that the discolouration is due principally to the presence of small quantities of coal, lignite, or similar discrete particles;

(ii) A fine aggregate failing in the test may be used provided that, when tested for mortar-strength properties accord-ing to CSA Standard A23.2.8, Mortar-Strength Proper-ties of Fine Aggregate, the mortar develops a compressive strength at 7 and 28 days of not less than 9S per cent of that developed by a similar mortar made from another portion of the same sample which has been washed in a 3 per cent solution of sodium hydroxide followed by thorough rinsing in water. The treatment shall be suffi-cient to produce a colour lighter than standard with the washed material;

(iii) A fine aggregate which entrains excessive amounts of accidental air and thereby produces concrete of abnor-mally low density and compressive strength may contain organic impurities which are not detectable by the colour test with sodium hydroxide. Such aggregate shall be rejected unless corrective measures are applied which are acceptable to the Engineer (see Appendix C).

4.4.3.3 Cement-A~~re~ate Reactivity. Fine aggregate for use in concrete that will be subject to frequent wetting, extended exposure to humid atmosphere, or contact with moist ground shall be free of reactivity with the alkalis in cement which may produce excessive expansion in, or cause deterioration of, concrete. Such reactive aggregate may be used only if corrective measures acceptable to the Engineer are applied.

Fine .aggregates which produce excessive expansion in mortar or con-crete through cement-aggregate reaction other than alkali reactivity shall not be used for concrete unless corrective measures acceptable to the Engineer are applied.

NOTE: .i",fethods for evaluating the potential reactivity of aggregates, and the application of corrective measures are discussed in Appendix B.

4.4.4 Soundness

4.4.4.1 Fine aggregate subjected to five cycles of the soundness test given in CSA Standard A23.2.9, Soundness of Aggregates by Use of Sodium Sulphate or :Magnesium Sulphate, shall not show a loss greater than:

(a) 8 per cent when using sodium sulphate; or (b) 12 per cent when using magnesium sulphate.

The loss shall be weighted in accordance with the grading of the sample, which should comply with the grading specified in Clause 4.4.2.1.

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4.4.4.2

Irrespective of the results of the sodium sulphate or magnesium sulphate soundness test, the Engineer may accept or reject fine aggregate on the basis of:

(a) Performance when tested in concrete subjected to freezing and thawing tests; or

(b) Performance of similar aggregate from the same source in concrete which has been exposed to weathering, similar to that to be encountered, for at least five years.

Freezing and thawing tests shall be in accordance with the latest issue of one of the following ASTlVl Standards:

(a) C290, Resistance of Concrete Specimens to Rapid Freezing and Thawing in Water;

(b) C291, Resistance of Concrete Specimens to Rapid Freezing in Air and Thawing in Water;

(c) C292, Resistance of Concrete Specimens to Slow Freezing and Thawing in Water or Brine; or

(d) C310, Resistance of Concrete Specimens to Slow Freezing in Air and Thawing in Water.

4.5 Coarse Aggregate

4.5.1 General Characteristics.

Coarse aggregate shall consist of hard, strong, uncoated, durable particles of crushed stone, gravel, or air-cooled blast-furnace slag, or a combination thereof, approved by the Engineer and conforming to the requirements of this Code.

4.5.2 Grading.

The sizes of coarse aggregate shall be selected from the standard sizes given in Table 3, in accordance with the criteria of Clauses 7.2.2 and 7.2.3. The method of determining gradation by sieve analysis shall be according to CSA Standard A23.2.2, Sieve Analysis of Fine and Coarse Aggrega tes.

4.5.3 Deleterious Substances

4.5.3.1

The amount of deleterious substances in coarse aggregate, each determined on independent samples complying with the grading requirements in Table 3, shall not exceed the limits prescribed in Table 4. Determinations shall be based on the following CSA Standards where applica bIe:

(a) A23.2.3, Clay Lumps in Natural Aggregates;

(b) A23.2.6, Scratch Hardness of Coarse Aggregate Particles; (c) A23.2.4, Lightweight Pieces in Aggregate; and

(d) A23.2.5, Amount of :Material finer than No. 200 Sieve 111

Aggregate.

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TABLE 3 GRADING REQUIREMENTS FOR COARSE AGGREGATES Total Passing, Each Sievet Nominal Per Cent By Weig,ht Size No.4 No.8 Group of 4 33-i 3 2~ 2 1% 1 ~ Y2 Vs (4760- (2380-Al\g,regate Inch Inch Inch Inch Inch Inch Inch Inch Inch Inch l\Ucron) Micron) 172 inch -100 9S to 3S to 10 to

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TABLE 4

LIMITS FOR DELETERIOUS SUBSTANCES IN COARSE AGGREGATE

Clay lumps Soft particles

Substances

Chert which will readily disintegrate (soundness test-five cycles)

Shale

Material finer than No. 200 sieve

Oven-dry material floating on a liquid having a specific gravity of 2.0

Total deleterious material not to exceed

Maximum Per Cent

by Weight of Total Sample 0.25 5.0 1.0 1.0 1. 0 (a) 1. 0 (b) 5.0

NOTES: (a) In the case of crushed aggregate, if the material finer than No. 200 sieve consists of the dust of fracture. essentially free from clay or shale. this percentage shall be 1.5 per cent.

(b) Does not refer to blast-furnace-slag coarse aggregate.

4.5.3.2 Cement-Aggregate Reactivity.

Coarse aggregate for use in concrete that will be subject to frequent wetting, extended exposure to humid atmosphere, or contact with moist ground shall be free of reactivity with the alkalis in cement which may produce excessive expansion in, or cause deterioration of, concrete. Such reactive aggregates may be used only if corrective measures acceptable to the Engineer are applied.

Coarse aggregates which produce excessive expansion in concrete through cement-aggregate reaction other than alkali reactivity shall not be used for concrete unless corrective measures acceptable to the Engineer are applied.

NOTE: Methods for evtLluating the potential reactivity of aggregates and lhe application of corrective measures are discussed in Appendix B.

4.5.4 Soundness

4.5.4.1 Soundness Test.

Coarse aggregate subjected to five cycles of the soundness test given in CSA Standard A23.2.9, Soundness of Aggregates by Use of Sodium Sulphate or :Magnesium Sulphate, shall not show a loss greater than:

(a) 10 per cent when using sodium sulphate; or (b) 15 per cent when using magnesium sulphate.

The loss shall be weighted in accordance with the grading of the sample which should comply with the grading specified in Clause 4.5.2.

4.5.4.2

Irrespective of the results of the sodium sulphate or magnesium sulphate soundness test, the Engineer may accept or reject coarse aggregate on the basis of:

(a) Performance when tested in concrete subjected to freezing and thawing tests: or

(b) Performance of similar aggregate from the same source in concrete which has been exposed to weathering, similar to that to be encountered for at least five years.

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CSA STANDARD A23 19

Freezing and thawing tests shall be in accordance with the latest issue of one of the following ASTM Standards:

(a) C290, Resistance of Concrete Specimens to Rapid Freezing and Thawing in Water;

(b) C291, Resistance of Concrete Specimens to Rapid Freezing in Air and Thawing in Water;

(c) C292, Resistance of Concrete Specimens to Slow Freezing and Thawing in Water or Brine; or

(d) C310, Resistance of Concrete Specimens to Slow Freezing in Air and Thawing in Water.

4.5.5 Weight of Slag.

Blast-furnace slag, conforming to the grading to be used in the concrete, shall have a compact weight of not less than 70 pounds per cubic foot, determined in accordance with CSA Standard A23.2.10, Unit Weight of Aggregate.

4.6 Lightweight Aggregate

4.6.1 Quality.

Lightweight aggregates shall conform to the require-ments of the latest issue of ASTl\1 Standard C330, Lightweight Aggregates for Structural Concrete.

4.6.2 Limitations.

Lightweight aggregates may be specified, or may be used on the written authority of the Engineer. \Vhen lightweight aggre-gates are used in concrete which will be exposed to weathering, the concrete shall have a specified compressive strength of at least 3,000 psi, and an air content (entrapped plus entrained) of at least 6 per cent.

4.6.3 Lightweight-Aggregate Concrete.

The proportions for light-weight-aggregate concrete shall be established following the procedure given in the latest issue of ACI Code 613 A, Recommended Practice for Selecting Proportions for Structural Lightweight Concrete.

5. OTHER MATERIALS

5.1 Admixtures

5.1.1 General.

Admixtures may be specified, or may be used on the written authority of the Engineer, and then only in the manner, and with the control, specified by the Engineer.

5.1.2 Air-Entraining Admixtures.

Air-entraining admixtures shall conform to the requirements given in the latest issue of ASTM Standard C260, Air-Entraining Admixtures for Concrete.

5.2 Water.

Water shall be clean and free from injurious amounts of oil, acid, alkali, organic matter, or other deleterious substances.

5.3 Reinforcement

5.3.1

Reinforcement shall be of the following classes, and the types used shall meet the requirements of the latest issue of the pertinent CSA Standards given, provided that other types of reinforcement may be used if approved by the Engineer:

(a) G30.1, Billet-Steel Bars for Concrete Reinforcement; (b) G30.2, Rail-Steel Bars for Concrete Reinforcement;

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(c) G30.3, Cold-Drawn Steel vVire for Concrete Reinforcement; (d) G30.4, Fabricated Steel Bar or Rod :\lats for Concrete

Reinforce-ment; and

(e) G30.5, vVelded Steel \Vire Fabric for Concrete Reinforcement.

5.3.2

Structural steel for composite columns shall meet the require-ments of the latest issue of one of the following CSA Standards:

(a) lVlild structural steel-G40.3, Structural Steel for Locomotives and or

(b) l\Iedium structural steel-G40.4, l\1edium Structural Steel.

5.3.3

Cast iron for composite columns shall meet the requirements of the latest issue of CSA Standard S6I, Cast Iron.

5.3.4

Hard Grade billet steel and rail steel shall not be used for stirru ps, column or beam ties, or spirals.

6. STORAGE OF MATERIALS

6.1 General

6.1.1

All materials shall be stored at the work in a manner which will prevent deterioration or contamination by foreign matter.

6.1.2

Any material which has deteriorated or has been contaminated shall not be used for concrete, and shall be removed from the site immedi-ately.

6.2 Cement

6.2.1

Cement shall be stored in a suitable weathertight bin or building which will protect it from dampness, and which permits easy access for proper inspection and identification of each shipment.

6.2.2

If cement becomes lumpy due to partial hydration it shall be removed from the job immediately.

6.3

A~gregates. Each size of aggregate shall be stored separately in a free-draining stockpile in a manner which will prevent breakage, deterioration, contamination, or segregation.

6.4 Other Materials.

Admixtures, curing compounds, and other materials shall be stored in accordance with the manufacturer's recommendations.

NOTE: Some of these materials are damaged if permitted to freeze.

7. PROPORTIONING

7.1 Classes of Concrete.

For the purpose of this Code, all concrete shall be classified either as "Controlled Concrete" (see Clause 7.4) or "Ordinary Concrete" (see Clause 7.5),

7.2 Mix Proportions

7.2.1

:\:1ix proportions shall be based on the water:cement ratio neces-sary to produce concrete of the specified strength as required in Clause 7.4 for controlled concrete, or Clause 7.5 for ordinary concrete, but in any case the water:cement ratio shall be not greater than that required for durability. Table Al of Appendix A may be used as a guide in specifying desirable water: cement ratios for durability.

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p

CSA STANDARD A23 21

7.2.2 Selection of Maximum Size of Aggregate.

The maximum nominal size of coarse aggregate consistent with the size of the forms, spacing of reinforcement, and equipment available for mixing and placing shall be used. The nominal size of aggregate shall be not larger than:

(a) One-fifth the narrowest inside dimension of the forms in which the concrete is to be placed; or

(b) Two-thirds of the minimum clear spacing between reinforcing bars.

7.2.3 Consistency.

The proportions of materials shall be such as to produce a mixture which will work readily into the corners and angles of the forms and around the reinforcement. T he mix proportions shall be such that the concrete will not easily segregate or cause excess free water to collect on the surface. Table A2 of Appendix A may be used as a guide in specifying consistency as determined by slump tests.

7.3 Air-Entrained Concrete.

\Vhen air-entrained concrete is specified or authorized by the Engineer, the concrete shall have a total air content (entrapped plus entrained) within 1 per cent of that specified in Table 5. Air content determinations shall be as specified in Clause 9.3.2.

TABLE 5

TOTAL AIR CONTENT OF AIR-ENTRAINED CONCRETE

Maximum Size of A~g,reg,a te _U ~

%:

1 1~ 2 2~ 3~ Inch Air Content 9 7 6 5 4.5 4 4 3.5 Per Cent

7.4 Controlled Concrete.

Controlled concrete shall mean concrete on projects where the cement and aggregates are to be measured by weight batching, and where frequent determinations are to be made of surface moisture of aggregates. Surface moisture determinations shall be in accor-dance with CSA Standard A23.2.11, Surface l\loisture in Fine Aggregate.

7.4.1 Trial Batches.

\Vhen a uniform and sufficiently large quantity of job materials is available, the water:cement ratio necessary to produce controlled concrete of the required quality may be established from strength tests on trial batches.

7.4.1.1

The water: cement ratios used in the trial batches shall be selected to cover the entire range of concrete required for the project.

7.4.1.2

Trial batches shall be prepared using the job materials and consistencies suitable for the work. Specimens for strength tests shall be moulded and cured in accordance with CSA Standard A23.2.12, .Making and Curing Concrete Compression and Flexure Test Specimens in the Laboratory.

7.4.1.3

At least four different water: cement ratios shall be used in the tria] batches, and from each mix at least three specimens shall be tested at 28 days, or at such earlier age as may be specified, according to

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22

CSA Standard A23.2.13, Compressive Strength of Moulded Concrete Cylinders.

7.4.1.4

From the data obtained in the tests of the trial batches, proportions shall be established which not only give average strengths 15 per cent more than the specified strength, but which also ensure that the water:cement ratio will not exceed that specified to fulfill the durability requirements.

7.4.2 Alternate Method for Proportioning the Mix of Controlled

Concrete

When trial batches as specified in Clause 7.4.1 are not made, the mix proportions for controlled concrete shall be established so that the water: cement ratio neither exceeds the values of Table 6, nor exceeds that specified for durability.

TABLE 6

MAXIMUM PERMISSIBLE WATER:CEMENT RATIOS

FOR CONTROLLED CONCRETE WHEN TRIAL MIXES ARE NOT MADE Maximum Water: Cement Ratio

Specified

Plain Concrete Air-Entrained Concrete Compressive

Strength

Imperial Gallons Ratio Imperial Gallons Ratio psi per Bag by Weight per Bag by Weight

2000 6 0.69 5~ 0.63

2500 5~ 0.63 5 0.57

3000 5 0.57 434' 0.49

3500 4~ 0.51 3~ 0.40

NOTE: In air-entrained concrete, the apparent penalty in strength is partially or entirely offset by the reduction in mixing water requirements which result from air entrainment, and from permissible reduction in the ratio of fine to coarse aggregate.

7.5 Ordinary Concrete.

When any of the solid ingredients of the mix are measured by volume, the proportions shall be established so that the water:cement ratio neither exceeds the values set out in Table 7 nor exceeds that specified by the Engineer to fulfill the durability requirements.

Specified Compressive Strength psi 2000 2500 3000 TABLE 7

MAXIMUM PERMISSIBLE WATER:CEMENT RATIOS FOR ORDINARY CONCRETE

Maltlmum Water:Cement Ratio

Plain Concrete Air-Entrained Concrete Imperial Gallons Ratio Imperial Gallons Ratio

per Bag by Weight per Bag by Weight

5~ 0.63 5 0.57

5 0.57 434' 0.49

472 0.51 3~ 0.40

7.6 Water Carried by Aggregates.

In determining the water:cement ratio, allowance shall be made for the surface water carried by the aggregate.

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$2

CSA STANDARD A23 23

Determinations of surface water carried by fine aggregate shall be made according to CSA Standard A23.2.11, Surface lVIoisture in Fine Aggregate. In the absence of tests, Table A3 of Appendix A is recommended as a guide.

8. CHECKING MIX DESIGN IN THE FIELD

8.1

General.

During the first stage of concrete placing, sufficient additional specimens shall be cast to permit determination of the actual properties of the concrete being mixed under field conditions.

8.2 Alterations to Mix Proportions.

The Engineer may permit, or demand changes in the mix proportions, depending upon the actual job conditions encountered.

9. FIELD CONTROL OF CONCRETE QUALITY

9.1 General.

All operations relating to mixing, placing, and curing shall be controlled by the Engineer. The contractor shall facilitate this by providing unhindered access to the work for purposes of inspection and selection of samples. The contractor shall provide the necessary protection for the specimens against injury or loss.

9.2

Stren~th

Tests

9.2.1

A strength test shall mean the average strength of three companion test specimens tested at the same age.

9.2.2

Specimens used as a basis for acceptance of concrete shall be made in accordance with CSA Standard A23.2.14, :Making and Curing Concrete Compression and Flexure Test Specimens in the Field. The specimens shall be cured under standard moisture and temperature conditions.

9.2.3

Additional tests of specimens cured entirely under field conditions may be required by the Engineer to check the adequacy of curing and/or cold weather protection.

\Vhen field-cured specimens are required, duplicate sets of test speci-mens shall be made. One set shall be cured under field conditions as specified in CSA Standard A23.2.14, :Making and Curing Concrete Compression and Flexure Test Specimens in the Field, and the other under standard moisture and temperature conditions as required in Clause 9.2.2.

NOTE: The laboratory-cured specimens will serve as a measure of the potential quality of the concrete.

9.2.4

Strength tests shall be made in accordance with CSA Standard A23.2.13, Compressive Strength of lVloulded Concrete Cylinders. Unless otherwise specified, the specimens shall be tested at the age of 28 days.

9.3 Number and Frequency of Tests

9.3.1 Compressive

Stren~th. Not less than one strength test (three specimens) shall be made for each 250 cubic yards of concrete, and in no case shall there be less than one test for each class of concrete placed on any one day.

9.3.2 Air Content.

Not less than one air content determination shall be made for each 100 cubic yards of air-entrained concrete placed, and in no case shall there be less than one air test for each class of concrete placed on

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anyone day. Air content determinations, except as noted below, shall be in accordance with one of the following CSA Standards:

(a) A23.2.17, Weight per Cubic Foot, Yield, and Air Content (Gravi-metric) of Concrete;

(b) A23.2.1S, Air Content of Freshly J\lixed Concrete by the Volumetric lVlethod; or

(c) A23.2.19, Air Content of Freshly Mixed Concrete by the Pressure l\lethod.

Where liglotweight aggregate concrete is used, air content determina-tions shall be by the volumetric method referred to above.

9.3.3 Slump Tests. At least one slump test shall be made for every compressive strength or air content test carried out. Slump tests shall be made in accordance with CSA Standard A23.2.20, Slump of Portland Cement Concrete.

9.3.4 Additional Tests. lVIore frequent tests shall be made if there is a distinct change in job conditions, or if required by the Engineer.

9.4 Sampling Concrete. Samples of concrete from which test specimens are moulded shall be secured in accordance with CSA Standard A23.2.21, Sampling Fresh Concrete.

9.5 Strength Requirements

9.5.1 To conform to the strength requirements of this Code, the average of all tests shall exceed the specified strength. When five or more tests of the same class of concrete are available, the average of any five consecutive tests shall be equal to, or greater than, the specified strength; no three consecutive tests shall fall below the specified strength, and no strength test shall fall below SO per cent of the specified strength.

The foregoing requirements do not apply to job-cured specimens.

9.6 Failure to Meet Test Requirements

9.6.1 If any of the criteria of Clause 9.5.1 are not met, the Engineer shall have the right to require one or more of the following:

(a) Changes in the mix proportions for the remainder of the work; (b) Additional curing on those portions of the structure represented by

the test specimens which failed;

(c) That cores be drilled from the portions of the structure in question and tested in accordance with CSA Standard A23.2.16, Securing, Preparing, and Testing Specimens from Hardened Concrete for Compressive and Flexural Strengths. The results of this test will help to ascertain whether or not the specimens previously tested were truly representative of the concrete in place; or

(d) Load testing of the structure or structural element in accordance with American Standard A89.1, Building Code Requirements for Reinforced Concrete.

9.6.2 If, after carrying out the requirements of Clause 9.6.1 the Engineer is not satisfied that the concrete in the structure is of the specified quality, he may demand a strengthening or replacement of those portions which failed to develop the required strength.

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CSA STANDARD A23 2S

10. MEASUREMENT OF MATERIALS 10.1 General

10.1.1 For controlled concrete, the measurement of cement and aggre-gates shctll be by weight.

10.1.2 For ordinary concrete, the materials may be measured either by weight or by volume.

10.1.3 All measuring means and device~ shall be subject to the approval of the Engineer, and shall be designed and arranged so as to permit rapid adjustments of quantities when required.

10.1.4 Gates and closing devices shall be positive in action, and shall prevent leakage of materials when in the closed position.

10.2 Water

10.2.1 Water may be measured either by weight or by volume.

10.2.2 Water-measuring devices shall be capable of measuring the quantity of water per batch within

±

1 per cent.

10.2.3 The operating mechanism in water-measuring devices shall be such that no leakage will occur when the valves are closed, and discharge valves cannot be opened until the filling valve is closed.

10.3 Allowance for Moisture Carried by the Aggregates. In the measurement of materials, due allowance shall be made for surface water carried by the aggregates. (See Clauses 7.4.1 and 7.6.)

10.4 Measurement by Weight

10.4.1 Cement, fine aggregate, and coarse aggregate shall each be weighed separately.

10.4.2 The accuracy of the weighing device shall be maintained so that the indicated weight does not vary by more than one-half of one per cent from true weight throughout its range of use.

10.4.3 The weighing equipment shall be capable of being operated to control delivery of material so that the combined inaccuracies in feeding and measuring do not exceed the following limits:

(a) Cement-1 per cent;

(b) Aggregate smaller than 17:2 inch-2 per cent; and (c) Aggregate larger than 17:2 inch-3 per cent.

10.4.4 Cement in standard sacks need not be weighed (except as required for a check), but the use of fractional sacks will not be permitted unless weighed.

10.5 Measurement by Volume

10.5.1 Separate measuring hoppers shall be provided for each size of aggregate.

10.5.2 Equipment for measuring all materials shall be readily adjust-able, and shall be arranged, when full and struck off, to measure the correct quantities of aggregates within

±

2 per cent, taking into consideration the change in unit weight and volume of the materials with changes in gradation and moisture content.

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10.6 Calibration of Measuring Devices

10.6.1

Facilities satisfactory to the Engineer shall be provided for calibrating batching devices.

10.6.2

The Engineer may require calibration before or during progress of the work, or when any changes in aggregate might affect volume-batched quantities.

11. MIXING

11.1 General.

Unless otherwise authorized by the Engineer, concrete shall be mixed in a mechanical batch mixer, of a type approved by the Engineer, and equipped with a suitable charging hopper and discharging device.

11.2 Mechanical Batch Mixing

11.2.1 Equipment

11.2.1.1

The drum, blades, and discharging device shall be such that the concrete is uniform in consistency and the materials are evenly distributed throughout the batch as it is discharged.

11.2.1.2

The mixer shall be cleaned after each period of con-tinuous use, and shall be maintained in such condition that the mixing action will not be impaired.

11.2.1.3

The mixer shall not be loaded beyond its rated capac-ity.

11.2.1.4

The entire contents of the mixer shall be discharged before recharging.

11.2.2 Time of Mixing and Revolutions

11.2.2.1

For mixers with a capacity of 1 cubic yard or less, mixing shall continue for a minimum of 1 minute after all the materials, in-cluding the mixing water, are in the drum. For larger capacities, the mini-mum time shall be increased by 15 seconds for each additional ~ cubic yard capacity or fraction thereof.

NOTE: The time of mixing specified above is a minimum, and appreciable increase in quality and strength of concrete is brought about by increasing the mixing time.

11.2.2.2

In all cases the mixing shall continue until there is a uniform distribution of materials, and the mass is uniform in colour and consistency.

11.2.2.3

Mixers shall be rotated at the rate recommended by the manufacturer of the mixer.

11.2.2.4

Where the use of an air-entraining agent is specified, the Engineer may stipulate a maximum permissible mixing period, depending upon the types of aggregates and air-entraining agent.

11.3 Ready-Mixed Concrete.

Ready-mixed concrete shall meet the requirements of Clause 12.

11.4 Hand Mixing

11.4.1

When hand mixing is permitted for ordinary concrete, the mix proportions shall be as directed by the Engineer.

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eSA STANDARD A23 27

11.4.2

Hand mixing shall be carried out on a watertight platform, and care shall be taken that mixing continues until the mass is uniform in colour and consistency.

NOTE: It is recommended that the entire mass be turned over completely seven times.

11.4.3

Hand mixing should not be permitted where the concrete is to . be air entrained.

11.5 Retempering.

The retempering of concrete or mortar that has stiffened (remixing with additional water) will not be permitted.

12. READY-MIXED CONCRETE

12.1 General

12.1.1

The basis of measure of ready-mixed concrete shall be the cubic yard of plastic and unhardened concrete as delivered to the purchaser.

12.1.2

The volume of plastic and unhardened concrete in a given batch shall be determined from the total weight of the batch divided by the actual weight per cubic foot of the concrete.

12.1.3

The total weight of the batch shall be calculated either as the sum of the weights of all materials, including water, entering the batch, or as the net weight of the concrete in the batch as delivered.

12.1.4

The weight per cubic foot shall be determined in accordance with CSA Standard A23.2.17, Weight per Cubic Foot, Yield, and Air Content (Gravimetric) of Concrete.

12.2 Materials

12.2.1

All materials shall be in accordance with the requirements of Clauses 3 to 5 of this Code.

12.3 Quality of Concrete

12.3.1

Unless otherwise specified, the purchaser shall select one of the two alternate bases as given in either Clause 12.3.1.1 or Clause 12.3.1.2 for specifying the quality of the concrete.

12.3.1.1 Alternate Number 1.

\Vhen the purchaser assumes responsibility for the design of the concrete mixture, he shall specify the following:

(a) Cement content in bags per cubic yard of 'oncrete, or equivalent units;

(b) Designated size, or sizes, of coarse aggregate;

(c) lVlaximum allowable water content in gallons per bag of cement, or equivalent units, including surface moisture but excluding water absorption of the aggregates;

(d) Slump, or slumps, at the point of delivery; (e) Admixtures if any; and

(f) The maximum and minimum air content of the concrete as determined from samples taken from the transportation unit at the point of discharge when an air-entrained con-crete is specified.