aci 301 specifications for structural concrete november 1

ACI 301 Minutes, November 2008

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ACI 301 Specifications for Structural Concrete November 1, 2, 3, 2008

St. Louis, MO Minutes

Meeting 1 1. The first meeting of ACI 301 was called to order at 12:10 pm on November 1.

2. The meeting was started by self introductions. The following were in attendance at one or more of the three meetings:

Voting Members Calvin McCall, Chairman David P. Gustafson Colin Lobo, Secretary Charles Hanskat Miroslav Vejvoda, ACI Staff Kenneth Hover Jon Ardahl Steven Jaycox Nick Carino Larry Krauser Ramon Carrasquillo Frank Malits Domingo Carreira Theodore Neff Mark Chrzanowski Jerry Parnes Steven Close Aimee Pergalsky James Cornell Henry Prenger Juan P. Covarrubias Michael Robinson Marwan Daye Scott Tarr Daniel Dorfmueller Michael Whisonant Barry Foreman Michelle L. Wilson Sidney Freedman Dennis Wittry John Gajda Bryan Wood

Non Voting Members Robert Jenkins Eldon Tipping Alfred Kaufman

Visitors Patrick Hazelwood, Omya Eric Peterson, Webcor

3 Chairman McCall indicated that ACI 301 was very close to completing the new proposed sections and clearing up outstanding balloted revisions to existing sections. These meetings would be dedicated to resolving negatives from prior ballots. He noted the addition of two new voting members – Krauser and Gajda.

4 The Committee addressed resolutions to items on formwork on Letter Ballot 06-01 item 2 that were subsequently reballoted in Letter Ballot 07-03.

4.1 LB 07-03, Item 28, Ref 130 (LB 06-01 Item 2, Ref 22). Negative by Carino. There was no motion to find the negative voters non-persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 18-0-0.

2.2.1.2 Formwork accessories – Use commercially manufactured and engineered accessories for formwork accessories that are partially or wholly embedded in concrete, including ties and hangers. Do not use non-fabricated wire form ties. Where indicated in the Contract Documents, use form ties in walls with integral water barrier plates in walls or other acceptable positive water barrier in walls.

O Indicate where walls require form ties with a positive water-barrier.


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4.2 LB 07-03 Item 41, Ref 145. Negative by Carrasquillo. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 19-0-0

2.3.2.7 Erect the form facing materials in an orderly and symmetrical arrangement, and keep the number of seams to a practical minimum. Erect form-facing materials to produce specified appearance and texture. Replace used form-facing materials containing holes, raised grain, torn surfaces, worn edges and dents that will that will impair the specified appearance and texture of exposed to view concrete surfaces.

4.3 LB 06-01, Item 2, Ref 43. Negative by Ardahl. A motion was made and seconded to find Ardahl non-persuasive because the section is covered in 2.2.2.3.e. The motion passed by a vote of 22-0-0.

4.4 LB 06-01 Item 2, ref 47. Negative by Ardahl. A motion was made and seconded to find Ardahl non-persuasive because this needed to be retained because this is what is done in practice. The motion passed by a vote of 22-0-0.

4.5 LB 06-01, Item 2, Ref 68, negative by Carino. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 22-0-0. Delete 2.3.2.6.

2.3.2.6 Construct formwork to permit easy removal.

4.6 LB 07-03, Item 35 Ref 137 (LB 06-01 Ref 37), negative by Carrasquillo. Hanskat withdrew negative on Ref 37 on 06-01. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

2.2.2.8 For a smooth form finish, set Design the form facing materials in an orderly and symmetrical arrangement, and keep the number of seams to a practical minimum. Design Provide form-facing materials to meet produce specified appearance and texture while keeping the number of seams to a practical minimum and to the extent possible, in coordination with the Contractors plans for placing the concrete. Facing materials shall be supported with studs or other backing capable of maintaining deflections within the tolerances specified in 2.2.2.4.

4.7 LB 07-03, Item 39, Ref 142, (LB 06-01, Ref 55), negative by Carrasquillo. A motion was made and seconded to find the negative voter non-persuasive because its acceptable for formwork to move and “minimize” means no movement. The motion passed by a vote of 22-0-0.

5 The Committee addressed resolutions to items on Industrial Floor Slabs on Letter Ballot 08-03

5.1 LB 08-03, Item 7, negatives by Carino, Carreira, Cornell, Hanskat, Hover, Lobo, and Wood. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 22-2-0.

11.1.3.2.a If specified, drying shrinkage test results for the proposed concrete mixture that are determined in accordance with ASTM C 157/C 157M except that 7 days of moist curing is to be used followed by at least 21 days of air drying.Unless otherwise specified, ultimate drying shrinkage potential with test results for the proposed concrete mixture determined in accordance with

S Concrete mixture shrinkage test results O Specify if shrinkage test results are to be submitted and the shrinkage limit required. Specify an alternative acceptable procedure to measure the concrete shrinkage. Ultimate concrete shrinkage may be predicted from early-age test results in accordance with ACI 209R-92 Eq. 2-9.


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ASTM C 157/C 157M using a 7-day moist cure and a minimum 21-day drying period in air storage.

S When required, concrete mixture shrinkage test results. O If desired, specify longer drying period for shrinkage data.

5.2 LB 08-03, Item 33, negatives by Carino, Hanskat, Jaycox, Lobo, Wittry, and Wood. Jaycox negative was withdrawn. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 20-0-1.

11.2.2 Performance Concrete Mixture Requirements Unless otherwise specified or permitted, proportion concrete mixture to satisfy the following:

• Specified cCompressive strength of 3500 psi at 28 days: at least 3500 psi;

• Compressive strength at 3 days: at least 1800 psi;• Slump: not greater thanMaximum 46 in. slump

when only water is used, or not greater than 6 in. when water-reducing admixture is used;

• Capable of being placed and finished to achieve a densified hard troweled finish; and

• The maximum ultimate shrinkage potential shall be 780 millionths in./in. unless otherwise permitted when specified in Contract Documents.

O Specify alternative or additional performance mixture requirements if desired. For example, a drying shrinkage of 780 millionths is the maximum value of the typical concrete range. A lower shrinkage may be required by the design. S Alternative mixture requirements. O If the ultimate shrinkage exceeds the specified value, see ACI 302.1R and 360R for guidance.

5.3 LB 08-03, Item 37, negative by Chrzanowsky. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 21-0-0

11.2.4 Reinforcement—When specified, use deformed bars, tendons, or deformed or plain welded-wire reinforcement meeting the requirements of 3.2 at the amounts specified in Contract Documents. Supports shall be used at a spacing to result in steel placement according to Contract Documents.

O When required, specify the type(s) of slab reinforcement and indicate the amounts and locations of slab reinforcement in Contract Documents. M Indicate slab reinforcement percentage and location in Contract Documents.

5.4 LB 08-03, Item 39, negative by Lobo. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 21-0-0.

11.2.6 Joint filler materials—Unless otherwise specified, uUse a two-component semi-rigid joint filler material in all joints as indicated in Contract Documents. The filler shall have 100% solids, a minimum Shore A hardness of 80 when measured in accordance with ASTM D 2240 and an elongation below 25 percent when measured in accordance with ASTM D 638.

O IndicateSpecify joints where joint filler is not required in Contract Documents. O Specify alternative joint filler material.

5.5 LB 08-03, Item 44, negative by Lee. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 20-0-2.

11.2.9 Liquid Surface Densifier– Use an acceptable liquid surface densifier in areas where specified.When required, use specified liquid surface densifier.

O Specify areas where densifier is to be used.acceptable liquid surface densifier if desired. S 11.1.3.2.h

5.6 LB 08-03, Item 45, negative by Lee. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

11.2.10 Mineral or metallic shake surface hardeners– Use an acceptable dry-shake surface hardener in areas specified.When required, use the specified solid surface hardeners.

O Specify areas where dry-shake surface hardener is to be used.Specify acceptable mineral or metallic shake surface hardeners if desired. S 11.1.3.2.i


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5.7 LB 08-03, Item 46, negative by Lee. A motion was made to find Lee non persuasive because base is the term used in ACI 302 and it will be defined in 301. The motion passed by a vote of 22-0-0. A definition for “base” will be balloted to address Hover negative on a separate item. From Item 3 a substantive revision was made to satisfy Ardahl negative – moved execution text to 11.3.1. The optional checklist item was added in response to Jaycox negative on Item 3. See 6.2.

11.3.1 Preparation – Unless otherwise specified, compact aggregate base course to at least 95 percent maximum density as tested in accordance with ASTM D 698. Comply with the requirements of 5.3.1 and verify that base surface elevation is within a tolerance of +0 in. and -1/2 in. of the planned elevation. This base surface elevation tolerance shall be maintained during placement of concrete.

O Specify compaction in accordance with ASTM D1557 when a higher base density is required.

5.8 LB 08-03, Item 52, negatives by Carino, Chrzanowski, Lee and Lobo. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

11.3.4 Finishing slab surface – Unless otherwise specified, comply with 5.3.4 except that the use of power equipment is acceptable. Do not begin finishing until bleeding has ceased and bleedwater sheen is absent. Water shall not be added to slab surface during finishing. When specified, apply accepted surface hardener according to manufacturer’s instruction.

O Specify if alternative finish is desired. Refer to ACI 302.1R for guidance. Consider requiring use of a highway straightedge to improve flatness. In addition, if aggregate shadowing appears while finishing concrete that has been optimized for shrinkage performance, consider requiring walk-behind power trowels equipped with float shoes as first pass instead of pan floats. O Specify when surface hardener is required.

5.9 LB 08-03, Item 57, negatives by Hanskat. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

11.3.6 Curing and protection – Unless otherwise specified, comply with 5.3.6 and provide curing for a minimum period of 7 days. Apply curing covers as soon as practicable without marring the finished surface. Place moisture-retaining coverings in a manner to prevent surface discoloration or marking. Keep the slab continuously wet after final finishing is completed and during the curing period. Temperature of applied water shall be within 10º F of concrete surface temperature. If a flooring finish or surface densifier is scheduled for installation, curing compounds, including those considered “self-dissipating”, shall be mechanically removed by method acceptable to finish flooring or surface densifier manufacturer.

O Specify if a curing period of less than 7 days is acceptable. O In dry or windy conditions, specify that slab and curing covers should be fogged or re-moistened periodically to prevent surface drying during the curing period.

5.10 LB 08-03, Item 59, negative by Carrasquillo, Cornell and Lee. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

11.3.7 Liquid Surface Densifier – Apply accepted acceptable liquid surface densifier in accordance with manufacturer’s recommendations. To promote penetration into concrete, the product shall be applied subsequent to the curing period, removal of curing compound, and after a 7-day period of drying. Remove all excess material in accordance with manufacturer’s instructions to minimize discoloring surface.


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5.11 LB 08-03, Item 60, negative by Cornell, Carino, Hanskat and Malits – There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 22-0-1. Hanskat negative. There was no motion to find the negative voter non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0.

11.3.8 Joint filling – Where indicated by Contract Documents, f Unless otherwise specified, fill construction and control joints with a semi-rigid joint filler. Install joint filler full-depth of sawcuts. When sawcutting construction joints, do not proceed until the sawing can be accurately aligned with joint. Unless otherwise specified, do not install joint filler earlier than recommended by filler manufacturer. Joints shall be slightly overfilled and shaved flush. Monitor joint filler during concrete drying period for separation (either adhesively or cohesively) as well as deterioration of the concrete along the joint as joints widen. Unless otherwise specified, separations shall be corrected within the first year of slab construction project warranty period separations shall be corrected.

O Specify joints not to receive semi-rigid filler due to anticipated hard-wheeled vehicle exposure. O Specify if joint filling should be performed at a time other than that recommended by the manufacturer. According to ACI 209R, 90% of the shrinkage can be expected to occur during the first 12 to 18 months under sustained drying. As concrete shrinks, joints widen. Joint widening causes filler separation that requires correction. O Specify if joint filler monitoring/correction should be extended for longer than the warranty period.

Meeting 2

The meeting was called to order on November 2 followed by self-introductions.

6 The Committee continued with resolutions to items on Industrial Floor Slabs on Letter Ballot 08-03

6.1 LB 08-03, Item 3 – negative by Ardahl, Carrasquillo, Cornell, Jaycox, and Wood. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. The motion passed by a vote of 23-0-0. (Also see 5.7)

11.1.2 General Requirements Concrete for industrial floor slabs shall comply with the requirements of Section 1 through 5 unless otherwise specified in this Section or on the Contract Documents. Unless otherwise specified, Industrial floor slabs shall be at least 6 in. thick and bear on at least 4 in. specified graded aggregate base.

O Specify requirements of Sections 1 to 5 that do not apply. O Specify if alternative base type is to be used or specify other provisions to reduce frictional restraint. O Specify if less than 6 in. thick slab or less than 4 in. specified graded base is allowed.

11.2.1.2.b Unless otherwise specified, aggregate used for base course shall be approved conform to by the local Department of Transportation ASTM D2940.

O Specify if alternative aggregate is acceptable for use as a base course material.

6.2 LB 08-03, Item 12 – negatives by Carino, Cornell, Hanskat and Wood. Hanskat and Wood negatives were withdrawn. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change to include revisions to 11.2.4 and 11.3.1. The motion passed by a vote of 22-0-0. (Also see 5.7)

11.1.3.2.c Product information sheet Manufacturer’s data sheet for vapor retarding sheet if a vapor retarder is required by Contract Documents.

O Specify locations where vapor retarder is required beneath concrete slab. S When required, product information Manufacturer’s data sheet for vapor retarder sheet when used.

11.2.4 Vapor Retarder – Unless otherwise specified, vapor retarder shall meet the requirements of conform to ASTM E 1745 Class A . Unless otherwise specified, vapor retarder and shall be at least minimum 10-mil thickness.

O Specify alternative vapor retarder material and required thickness of vapor retarder if less than 10-mil.

11.3.1 Preparation – Unless other wise specified, c O Specify compaction in accordance with ASTM


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Compact theaggregate base course to at least 95 percent of maximum density as tested in accordance with ASTM D698. Comply with the requirements of 5.3.1 and verify that base surface elevation is within a tolerance of +0 in. and -1/2 in. of the planned elevation. This base surface elevation tolerance shall be maintained during placement of concrete. Install acceptable vapor retarder in accordance with ASTM E 1643 directly beneath slab in areas shown on the Contract Documents. Lap all seams at least 6 in. and tape continuously.

D1557 when a higher base density is required. M Indicate areas where a vapor retarder is required directly beneath slab.

6.3 LB 08-03, Item 29. Negative by Lobo and Lee. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. 11.2.1.1.a deleted. Changes in materials are addressed in 4.2.1.5.The motion passed by a vote of 23-0-0.

11.2.1.1.a When use of a different type, brand, or source of cementitious materials is permitted, resubmit revised mixture proportions and the results for specified tests including all required tests.

S Request to change type, brand or source of cement. S Resubmittal of concrete mixture if there is a change in type, brand, or source of cementitious materials.

6.4 LB 08-03, Item 30, negative by Lobo and Lee. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. Changes in materials are addressed in 4.2.1.5. The motion passed by a vote of 23-0-0.

11.2.1.2.a Unless otherwise specified or permitted, use aggregates with a nominal maximum size of 1½ in. conforming with requirements of 4.2.1.2.. When the aggregate sources are changed, the revised concrete mixture, including all required test results, shall be resubmitted.

O Specify aggregate requirements if ASTM C 33 requirements are insufficient or if alternative nominal maximum size is desired. More restrictive gradation or limitations of lignite, coal, or other deleterious substances may be required. See ACI 302.1R for further guidance. S Resubmittal of concrete mixture if change in aggregate source occurs.

6.5 LB 08-03, Item 32, negative by Lobo and Lee. There was no motion to find the negative voters non-persuasive. A motion was made accept a substantive change. Article deleted. Changes in materials are addressed in 4.2.1.5. The motion passed by a vote of 23-0-0.

11.2.1.3.c When type, brand, or source of admixture is permitted to be changed, submit revised concrete mixture along with all required test results.

S Request to change admixture type, brand, or source. S Resubmittal of concrete mixture if change in type brand or source of admixture is permitted.

6.6 LB 08-03, Item 49, negative by Carreira was withdrawn. Article 11.3.3.1 will be reballoted for possible deletion as it is covered by 4.3.2.1 and ASTM C 94.

6.7 LB 08-02, Item 8, ref 92, Hanskat negatives. A motion was made to accept substantive changes to 11.3.8, 11.3.5.2 on two parts of Hanskat negatives. The motion passed by a vote of 23-0-0. A motion was made to find Hanskat non persuasive on part 3 of his negative because “as joints move” is advisory and cannot be in the specification and the intent is to address joint filling of joints that widen and on part 4 of his negative because deterioration is better term than proposed language. The motion passed by a vote of 21-0-0.

11.3.8 Joint filling – Unless otherwise specified, fill joints with a semi-rigid joint filler. Install joint filler full-depth of sawcuts. Unless otherwise specified, do not install joint filler earlier than recommended by filler manufacturer. Joints shall be slightly overfilled and shaved flush. Monitor joint filler during concrete drying project warranty period for separation (either adhesively

O Specify joints not to receive semi-rigid filler. O Specify if joint filling should be performed at a time other than that recommended by the manufacturer. According to ACI 209R, 90% of the shrinkage can be expected to occur during the first 12 to 18 months under sustained drying. As


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or cohesively) as well as deterioration of the concrete along the joint as joints widen. Unless otherwise specified, separations shall be corrected within the project warranty period.

concrete shrinks, joints widen. Joint widening causes filler separation that requires correction. O Specify if joint filler monitoring/correction should be extended for longer than the warranty period.

11.3.5.2 Construction joints – Comply with 2.2, 2.3, and 5.3. Construction joints shall be perpendicular to slab surface and shall not be constructed using keyways. Unless otherwise specified, doweled construction joints designed to allow widening shall be sawcut to ¼ slab thickness or 2 in., whichever is smaller. Align sawcut with joint.

O Specify construction joints that do not have to be sawcut. Joints trafficked by hard-wheeled vehicles should be sawcut and filled with a semi-rigid joint filler.

6.8 LB 08-03, Item 36. Negatives by Cornell and Wilson. Cornell negative related to changing the maximum concrete temperature to 95°F. Proposed changes need to be reballoted.

7 The Committee addressed resolutions to negatives on items on precast concrete on Letter Ballot 08-01

7.1 LB 08-01, Item 6, Ref 72, negatives by Carino, Carreira, Hover, Lee and Prenger. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 24-0-0. A motion was made to find Lee non persuasive because chloride requirements are addressed in section 4. The motion passed by a vote of 24-0-0.

13.2.9.2 Normalweight Concrete Mixtures: Unless otherwise specified, concrete shall meet the requirements of Section 4, with the exceptions that specified compressive strength at 28 days shall be at least 5000 psi, and the maximum water-cementitious materials ratio shall be 0.40 proportion mixtures by either laboratory trial batch or field test data methods according to Section 4 with materials to be used on Project, to provide normalweight concrete with the following properties:

Minimum Specified compressive strength at 28 Days: at least 5000 psi.

Release strength: As required by Contract Documents.

Maximum water-cementitious materials Ratio: 0.45 unless otherwise specified.

Air entrained concrete as required in ACI 301, Chapter 4 unless otherwise specified or permitted

M Specify minimum concrete strength at release of prestressing force. O Specify different alternative compressive strength, when required. Higher-strength mixtures may be available, verify availability with fabricators. O Specify if higher w/cm. Value of w/cm must meet requirements of Section 4. lower w/cm is required to suit Project. O – Specify air content

7.2 LB 08-01, Item 6, Ref 73, Negatives by Carino, Carreira, Chrzanowski, Hover and Lee. Chrzanowski and Carino negatives were withdrawn. There was no motion to find negatives by Carreira and Hover non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 23-0-0. A motion was made to find Lee non persuasive because chlorides are covered in Sec 4. The motion passed by a vote of 24-0-0.

13.2.9.3 Lightweight Concrete Mixtures: When Proportion lightweight concrete is specified, proportion mixtures by either laboratory trial batch or field test data methods according to Section 7, with materials to be used on Project Unless otherwise specified or permitted, to provide lightweight concrete with the following properties:

Minimum Specified compressive strength at 28 Days: at least 5000 psi.

Release strength: As required by Contract Documents.

M Specify when lightweight concrete is required.Specify minimum concrete strength at release of prestressing force and O Specify different alternative 28 day compressive strength and equilibrium density when if required. Coordinate with lightweight aggregate supplier and precast concrete fabricator. Some combinations of lightweight and normalweight aggregates in lightweight concrete mixtures may produce densities greater than 115 lb./cu. ft.


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Equilibrium density of 115 lb./cu. ft calculated equilibrium density according to ASTM C 567.

Air entrained concrete as required in ACI 301, Chapter 4 unless otherwise specified or permitted

O – Specify air content S Alternative equilibrium density

7.3 LB 08-01, Item 8, Ref 89, Hanskat negative. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 23-0-0.

13.2.12.5.b. Place reinforcing steel and prestressing steel within tolerances specified in ITG 7 to maintain at least ¾ in. concrete cover or concrete cover required by Contract Documents. Arrange, space, and securely tie bars and reinforcement supports to hold reinforcement in position while placing during concrete placement and consolidation operations. Position wire tie ends away from exposed concrete surfaces.

O Specify increased concrete cover if required by building code or if units will be exposed to corrosive environment or severe exposure conditions.

7.4 LB 08-01, Item 14, Ref 140, negatives by Jaycox and Wood. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 23-0-0.

13.3.3.4.c For galvanized metal, clean weld affected metal surfaces with chipping hammer followed by brushing or power tool cleaning. Inspect welds for defects. After welds satisfy AWS D1.1 weld acceptance requirements, have passed the required testing or inspection are found satisfactory accepted apply at least a 4 mil thick coat of galvanized repair paint to galvanized surfaces in conformance with ASTM A780.

7.5 LB 08-01, Item 15, Ref 146, Hanskat negative was withdrawn for consideration as new business. An editorial revision was accepted.

13.3.3.6 Grouting or Dry Packing Connections and Joints: Joints and connections to be grouted and critical grouting sequences shall be as indicated on Shop Drawings. Grout connections and joints where required or indicated on Shop Drawings. Retain Ensure grout remains in place until strong enough to support itself. Pack spaces with stiff grout material, tamping until voids are completely filled. Place grout and finish smooth and flush with adjacent concrete surfaces. Promptly remove grout material from exposed surfaces before it affects finishes or hardens. Keep grouted joints damp for at least 24 hours.

7.6 LB 08-01, Item 20, Ref 206 – 218. Carino negative was withdrawn. These articles will be reballoted.

7.7 LB 08-01, Item 21, Ref 239, Cornell negative. There was no motion to find the negative voter non persuasive. A motion was made and seconded to accept a substantive change. The motion passed with a vote of 24-0-0. Hanskat’s negative on Item 21, Ref 240 was withdrawn with this resolution.

14.2.13.1 Furnish and install sealant backings and sealant into stone-to-stone joints and stone-to-concrete joints on each unit. Unless otherwise permitted, apply a continuous sealant bead along both sides and top of precast concrete units at the stone/precast concrete interface. using the bond breaker as a joint filler backer. Do not seal bottom edge of unit.

S Request to modify sealant installation


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8 The Committee addressed resolutions to negatives on items on Section 5 on Letter Ballot 08-04 (original ballot 07-04)

8.1 LB 08-04, Item 7, negative by Carreira was withdrawn. Negative by Neff. There was no motion to find the negative voter non persuasive. A motion was made and seconded to accept a substantive change. The motion passed with a vote of 22-0-0.

5.3.2.5 Consolidating—Unless otherwise specified in Contract Documents, consolidate concrete by vibration. Consolidate concrete Ensure consolidation of concrete around reinforcement mechanical steel load transfer dowels in slabs and embedded items and into corners of forms, eliminating air and stone pockets that may cause honeycombing, pitting, or planes of weakness. Unless otherwise specified, Use use internal vibrators of the largest size and power to consolidate the concrete. properly be used in the Work as described in Table 5.3.2.5. Use immersion-type vibrators with nonmetallic heads when consolidating concrete around epoxy-coated reinforcement. Workers shall be experienced in use of the vibrators. Do not use vibrators to move concrete within the forms. Spacing of immersion vibrator insertions shall not exceed 1-1/2 times the vibrator’s radius of action in the concrete being consolidated.

OM: Specify mix types Specify if consolidation is not required or when using types of concrete mixtures that have intentional and accepted approved fluidity or self-consolidating characteristics. Specify types of concrete mixtures that do not require consolidation should not be vibrated due to their intentional and approved fluidity or self-consolidating characteristics. O: Specifiers may require Specify particular vibrator characteristics. ACI 309R Table 5.1.5 provides guidance. as described in Table 5.1.5 of ACI 309R.

8.2 LB 08-04, Item 8, negatives by Neff, Lee and Tarr. The item fails and reverts to original language (item originally balloted 07-04 item 20).

8.3 LB 08-04, Item 9, negatives by Neff, Wood and Carino. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change considering Neff’s negative (appreciable indentation). The motion passed by a vote of 23-0-1. A motion was made to accept a substantive change to address negatives by Wood and Carino. The motion passed by a vote of 24-0-2.

5.3.4.2.f Heavy-duty topping for two-course slabs— For heavy-duty topping mixture, use the materials and methods specified in Contract Documents. Place and consolidate concrete for the base slab, and screed concrete to the specified depth below the top of the finished surface. Topping placed the same day as the base slab shall be placed as soon as bleedwater in the base slab has disappeared and the surface will support a person with a bootprint depth of less than ¼ in. without appreciable indentation. When topping placement is to be deferred, prepare the surface to ensure bond between the base slab and topping. .until after final setting of the base slab , brush the surface of the base slab with a coarse wire broom to remove laitance and scratch the surface to a depth of at least ¼ in. (1/4 inch profile) when concrete is plastic before the base slab concrete reaches final setting. Wet-cure the base slab continuously for at least three days. Before placing the topping, clean the base slab surface thoroughly of contaminants and loose mortar or aggregate. Dampen the surface, leaving it free of standing water. Unless otherwise specified or permitted, immediately before placing topping, scrub into the slab surface a coat of bonding grout consisting of equal bulk volumes of parts of cement and fine sand meeting the requirements of

O For heavy-duty topping for two-course slabs, specify the materials, the final finishing method, and the location. O Specify when bonding agents other than cement grout are permitted or required. S Request to use bonding agents other than cement grout.


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ASTM C144 or ASTM C404 with enough water to make a creamy mixture. Do not allow grout to set or dry before topping is placed. Bonding agents other than cement grout are permitted may be used with prior acceptance. Spread, consolidate, compact, and float the topping mixture. Check for flatness of surface and complete operation with a floated, troweled, or broom finish as specified in the Contract Documents.

8.4 LB 07-04, Item 13, Ref 22, negative by Wood was withdrawn.

8.5 LB 07-04, Item 14, negative by Carino. Article 5.3.1.5 covers conditions to prevent plastic shrinkage cracking. After discussion it was decided to revert to existing language.

8.6 LB 08-04, Item 10, Ref 3. Negatives by Carino, Neff, Krauser Hanskat, Lee, and Malits. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 20-1-1. Wood voted negative. A motion was made to find Wood non persuasive because the A/E has the option to specify alternative curing. The motion passed by a vote of 20-0-2.

5.3.6.1 Curing—Unless otherwise specified or permitted, cure Cure concrete in accordance with 5.3.6.2 or 5.3.6.3 for at least a minimum of seven days after placement. Cure high-early-strength concrete for at least a minimum of three days after placement unless otherwise specified. Alternatively, When permitted, and when the duration of curing is to achieve a specified level of in-place strength, moisture retention measures may be terminated when any one of the following conditions have been met, unless specified otherwise:

O. The measures specified in 5.3.6 are for final curing of the concrete. Specify initial curing in accordance with ACI 308.1 for additional protection against loss of moisture from the time of placement to the time of initiating final curing measures. Initial curing measures are beneficial when bleed rate is expected to be low due to use of supplementary cementitious materials such as fly ash, slag, or silica fume, high air content, or low w/cm, or when evaporative conditions are likely to be severe during placing and finishing. Additional guidance is available in ACI 308R-01. O For concrete surfaces that require enhanced

durability, such as high wear resistance, low permeability, or minimal cracking, a longer duration of curing may be needed than is required to meet compressive strength criteria alone. When such enhanced properties are required, minimum curing periods of 7 days for high-early-strength concrete, 14 days for concrete incorporating Type I or Type II cements, and 14 to 21 days for concrete incorporating pozzolan as one of the cementitious materials are recommended. Specify a longer duration of curing as appropriate to the performance requirements of the concrete. See ACI 308.1 308R-01 for additional guidance. Specify if a curing procedure of 5.3.6.4 that supplies additional water is required. O. Specify if one of the three criteria for terminating curing, or of some other criterion for terminating curing is required. S Request for a shorter duration for moisture retention measures. Submit a request to use shorter duration for moisture retention, or if a curing method other than that specified is desired.


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8.7 LB 08-04, Item 10, Ref 4, negatives by Carino and Carrasquillo. Carrasquillo negative was withdrawn. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 20-0-0.

a. Tests made on at least two cylinders kept adjacent to the structure and cured by the same methods as the structure indicate that 70% of fc′, as determined in accordance with ASTM C 39/C 39M, has been attained; a. Tests made on at least two 6 by 12 in. or at least three 4 by 8 in. cylinders, which have been field cured in accordance with ASTM C31/C31M, indicate compressive strength of at least 70 % of f'c when tested in accordance with ASTM C39/C39M.Tests made on at least two 6x12 or at least 3 4x8 cylinders, cured and protected in such a manner as to experience the same temperature and moisture conditions as the structure, have the same kept adjacent to the structure and cured by the same methods as the structure indicate that 70% of fc

′, as determined in accordance with ASTM C 39/C 39M, has been attained;

8.8 LB 08-04, Item 10, Ref 5, editorial revisions were accepted.

c. Strength of concrete reaches fc′ as determined by

accepted nondestructive test in-place test methods meeting the requirements of 2.3.4.2.

8.9 LB 08-04, Item 10, Ref 6, Neff negative was withdrawn. Editorial revisions were accepted.

When one of the curing procedures in 5.3.6.4 is used initially, the curing procedure may be replaced by one of the other procedures, when after concrete is one day old, when the duration of curing is to achieve a particular level of in-place strength, and provided the concrete is not permitted to become surface-dry at any time. Use a curing procedure of 5.3.6.4 that supplies additional water during the entire curing period for concrete containing silica fume and when specified in the Contract Documents.

O Specify if supplying additional water is required for entire curing period.

8.10 LB 07-04, Item 23, ref 32, negative by Carino. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 24-0-0.

5.3.3.4.b Grout-cleaned rubbed finish—When specified, begin Begin cleaning operations after contiguous surfaces to be cleaned are completed and accessible. Do not clean surfaces as work progresses. Wet the surface and unless specified otherwise, apply grout consisting of one part by volume portland cement and one and one-half parts sand meeting the requirements of ASTM C 144 or ASTM C 404, with enough one-half parts ASTM C144 or ASTM C404 masonry fine sand with enough water to produce the consistency of thick paint. Match color of surrounding concrete to which grout is applied. Scrub grout into voids, and remove excess grout. When color of grout becomes lighter due to drying whitens, rub the surface and keep the surface damp for 36 h afterward.

O.M. Designate those portions of the structure to receive a grout-cleaned rubbed finish O. Specify alternative grout requirements. One example may be matching the color of grout to color of concrete surface to which grout will be applied. Where color is a concern, consider including a statement that when color of grout becomes lighter due to drying, rub the surface and keep the surface damp for 36 h afterward.

8.11 LB 07-04, Item 23, Ref 33. Negative by Carino. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 24-0-0.


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5.3.3.4.c Cork-floated finish—When specified, perform Perform necessary repairs. Remove ties, burrs, and fins. Wet the surface and unless specified otherwise, apply stiff grout of one part portland cement and one part fine sand by volume meeting the requirements of ASTM C 144 or ASTM C 404, filling voids. Match color of surrounding concrete. Use enough water to produce a stiff consistency. Compress grout into voids by grinding the surface with a slow-speed grinder. Produce the final finish with cork float, using a swirling motion.

O. M. Designate those portions of the structure to receive a cork-floated finish O. Specify alternative grout requirements. One example may be matching the color of grout to color of concrete surface to which grout will be applied.

8.12 LB 07-04, Item 25, ref 35. Negative by Anderson. A motion was made to find the negative voter non persuasive because the specification does not have to define the contents of an evaporative retarder. The motion passed by a vote of 24-0-0. Editorial revisions were accepted.

5.3.4.1 Placement—Place concrete at a rate that allows spreading, straightedging, and darbying or bullfloating before bleed water appears. Strike smooth the top of walls, buttresses, horizontal offsets, and other similar unformed surfaces and float them to a texture consistent with finish of adjacent formed surface. Finish slab surfaces in accordance with one of the finishes in 5.3.4.2, as designated in the Contract Documents. Conduct finishing operations so that the properties of the concrete at the finished surface meet specified requirements for strength and durability. Use qualified flatwork finishers acceptable to the Architect/Engineer. Unless otherwise specified or permitted, a minimum of one finisher or finishing supervisor shall be a certified ACI Flatwork Concrete Finisher/Technician or a certified ACI Flatwork Technician as defined in ACI CP 10 or equivalent.

S Request for acceptance of flatwork finishers’ qualifications. S Request to allow variation from required number of certified finishers and finishing supervisors.

5.3.4.2.c Trowel finish—Float concrete surface, then power-trowel the surface. Hand-trowel the surface smooth and free of trowel marks. Continue hand-troweling until a ringing sound is produced as the floor is troweled. Tolerances for concrete floors shall be for a conventional surface in accordance with ACI 117 unless otherwise specified. Tolerance for concrete floors shall be conventional straightedged tolerance in accordance with ACI 117 unless otherwise specified. Addition of water to surface during finishing is prohibited.

O Specify more restrictive tolerances if applicable. The conventional straightedged tolerance from ACI 117 applies to most general floor construction. For floors requiring tighter tolerances, such as in areas housing sensitive test or monitoring equipment, specify either “flat” or “very flat” floor tolerances from ACI 117. Refer to the commentary for ACI 117 and ACI 302.1R for more guidance. Specify tolerances that may be more or less restrictive when applicable.

9 The Committee addressed resolutions to items from Section 1 on Letter Ballot 08-04

9.1 LB 08-04, Item 2, negatives by Carreira, Jaycox, Lobo, Neff, Chrzanowski, Lee, Malits, and Wood. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion failed by a vote of 7-12-3. Item was withdrawn and language reverts to prior version.

9.2 LB 08-04, Item 3, negatives by Wittry, Carreira, Neff, Jaycox, Chrzanowski, Krauser, Lee, Malits and Wood. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion failed by a vote of 4-18-0. Item was withdrawn and language reverts to prior version.

9.3 LB 08-04, Item 4. Negatives by Pergalsky and Gajda. There was no motion to find the negative voters non persuasive. Item was withdrawn and language reverts to prior version.


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9.4 LB 08-04, Item 5. Negative by Carreira was withdrawn. Item was approved.

9.5 LB 08-04, Item 6, Ref 1 and 2. Negative by Chrzanowski, Ardahl and Lee. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed with a vote of 18-2-1 with Carreira and Tadros voting negative. A motion was made to find Carreira non persuasive because project specific definition of surface defect is the only workable definition. The motion passed by a vote of 21-1-1. A motion was made to find Tadros non persuasive because the words deleted from the balloted definition are not necessary in the specification and are suited better to the checklist. The motion passed by a vote of 19-3-0.

1.2— Definitions surface defects—features in concrete surfaces that exceed permitted limits stated in Contract Documents; limits are stated typically in terms of dimensions, frequency of occurrence, or visibility under prescribed conditions. surface defects—imperfection in concrete surfaces defined in Contract Documents that must be repaired.

5.3.7 Repair of surface defects 5.3.7.1 General—Repair tie holes and other surface defects, as defined in Contract Documents, immediately after formwork removal, unless otherwise permitted. Where the concrete surface will be textured by sandblasting or bush-hammering, repair surface defects before texturing.

M Describe in Contract Documents what will be considered as surface defects that must be repaired. M Provide in Project Documents project-specific definition of surface defects. Such definition may include dimensions, frequency of occurrence and visibility under prescribed conditions. S Request to delay repair of tie holes and surface defects

10 The Committee addressed resolutions to items on the section on mass concrete on Letter Ballot 08-02

10.1 LB 08-02, Item 1, Ref 4. Negatives by Carreira, Covarrubias, Lee and Prenger. Prenger negative was withdrawn. There was no motion to find Carreira non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 22-0-0. A motion was made to find Lee non persuasive because the minimum dimension in the current document is too restrictive. The motion passed by a vote of 22-0-0. A motion was made to find Covarrubias non persuasive because cement factor applies to mass concrete and this is not being changed from the current language. The motion passed by a vote of 18-4-0.

8.1.1.1 Scope—This section covers requirements for mass concrete as designated in Contract Documents.

O M -Designate portions of the structure to be treated as either plain mass concrete or reinforced mass concrete. Concrete placements where maximum temperatures and temperature differences must be controlled due to factors including the cementitious content, the type of cementitious materials, the environment surrounding the placement, and minimum dimension of the placement should be designated mass concrete. O Whether or not concrete should be designated as mass concrete depends on many factors such as weather conditions, the volume-surface ratio, rate of hydration, degree of restraint to volume change, temperature and mass of surrounding materials, and functional and aesthetic effect of cracking. In general, heat generation should be considered when the minimum cross-sectional dimension approaches or exceeds 2-1/2 ft or when cement contents above 600 lb/yd3 are used. The requirements for each project, however, should be


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evaluated on their own merits. In general, any placement of structural concrete with a minimum dimension that is equal to or greater than 5 4 ft should be considered mass concrete. Similar considerations should be given to other concrete placements that do not meet this minimum dimension but contain Type III cement, accelerating admixtures, or cementitious materials in excess of 660 lbs/yd3 of concrete. Consideration should also be given to placements that trap heat.

10.2 LB 08-02, Item 2, Ref 12. Negatives by Ardahl, Carino, Carrasquillo, Carreira, Hanskat, Lee, Lobo, Malits, Prenger and Wood. A motion was made to find Ardahl non persuasive because the selection of cement does not necessarily relate to durability. The motion passed by a vote of 22-0-0. A motion was made to find Carrasquillo non persuasive because Class C fly ashes are higher in heat generation. The motion passed by a vote of 22-0-0. A motion was made to find Lee, Carreira and Lobo non persuasive because limits on SCMs are in Section 4. The motion passed by a vote of 22-0-1. There was no motion to find Carino, Hanskat, Malits and Wood non persuasive. A motion was made to accept a substantive change. The substantive change also included Ref 11 and the sequence of the two articles was switched. The motion passed by a vote of 18-0-0.

8.2.1.1.a bUnless otherwise specified or permitted, use moderate heat of hydration portland cement, blended hydraulic cement with moderate or low heat of hydration properties, or portland cement with fly ash, pozzolan, or ground-granulated blast-furnace slag a hydraulic cement with moderate to low heat of hydration properties; or use a portland cement with Class F fly ash or slag cement, or both.

O- Specify if other types of cementitious materials are allowed. Class C fly ash can reduce the temperature rise of the concrete, but not as much as is typically achieved through the use of class F fly ash. O- Specify maximum allowable quantities of supplementary cementitious materials. In many mass concrete placements, fly ash makes up 40 to 50% of the cementitious materials, or slag cement makes up 50 to 75% of the cementitious materials. Ternary mixes are also sometimes used. Reduced replacement levels are sometimes required due to durability concerns related to environmental exposure as addressed in Section 4 and ACI 318. Because concretes with low heat-of-hydration cements or high replacement levels of slag cement or fly ash generally have delayed time of setting and lower early strengths, the early-age implications on setting times, form pressures, formwork removal, cylinder handling, duration of curing, and post-tensioning must be considered. When slag cement is less than 50% of the cementitious materials, the adiabatic temperature rise may be higher than if slag cement is not included in the cementitious materials. S- Request to use alternative cementitious materials.

8.2.1.1.ab Do not use ASTM C 150 Type III cement, or ASTM C 1157 HE cement, unless otherwise specified.

O- Specify if Type III high early strength cement should be permitted, provided that when the thermal control plan adequately demonstrates that the specified maximum temperature and temperature difference limits will not be exceeded.

Meeting 3

The meeting was called to order on November 3 followed by self-introductions.


15

11 Chairman McCall discussed the plan for publishing document. It was anticipated that the document would be submitted to TAC at the end of January and the Committee would deal with TAC comments at the Spring Convention. One additional letter ballot was planned and at least four virtual meetings would be scheduled. After the Committee completed addressing TAC comments the document would be posted for public review. Items related to ITG-7 have to be resolved. ACI 117 on tolerances is in the TAC review process and referencing 117 will be approved by a letter ballot. It was proposed to form a task group to address performance based specification requirements applicable in ACI 301.

12 The minutes of the meetings in March 2008 in Los Angeles and those of virtual meetings on July 7, September 3, 24 and 30 and October 20 and 27 were approved as distributed. Minutes of the virtual meeting on August 12 were not completed and will be approved at a future date.

13 The Committee continued resolutions to items on the section on mass concrete on Letter Ballot 08-02

13.1 LB 08-02, Item 1, Ref 5. Negatives by Carino, Carreira, Lee, Lobo and Prenger. There was no motion to find Lee and Lobo non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 18-0-0. Lobo withdrew part of negative related to temperature limit. Prenger negative was withdrawn. A motion was made to find Carino and Carreira non persuasive because the industry research-based published number for temperature limit is 158°F. The motion passed by a vote of 17-0-1

8.1.1.2 General requirements—Mass concrete, either plain or reinforced, shall comply with the requirements of Sections 1 through 5 unless otherwise specified in this section Section or in the Contract Documents. For all placements designated as mass concrete, the following criteria shall apply, unless otherwise specified:

• The maximum temperature in the concrete after placement shall not exceed 158°F.

• The maximum temperature difference between the center and surface of the placement shall not exceed 35°F.

M Review Sections 1 through 5 and specify additional requirements or any requirements to be omitted for mass concrete. O- Specify if the maximum temperature limit in the concrete after placement shall be other than 158°F. The maximum temperature is limited to prevent future durability concerns due to delayed ettringite formation [DEF] and potential reductions in the ultimate strength. Concretes that utilize a high proportion of supplementary cementitious materials may not be susceptible to DEF and a maximum temperature limit of 185°F may be justifiable. O- Specify if the maximum temperature difference limit in the concrete after placement shall be other than 35°F. The temperature difference must be limited to minimize or prevent thermal cracking. A higher temperature difference limit may be acceptable depending on the concrete properties, the dimensions of the placement, and the reinforcing steel configuration. The temperature difference limit for a specific concrete mixture and placement conditions can be determined through modeling numerical simulations and comparing thermal stresses to tensile strain capacity [tensile strength]) or through equations in ACI 207.2R.the computed thermally induced strains with the tensile strain limit of the concrete.

13.2 LB 08-02, Item 1, Ref 6, negatives by Ardahl, Carrasquillo, Chrzanowski, Lobo and Wood. A motion was made to find Ardahl and Lobo non persuasive because the thermal control plan should be required for mass concrete. The motion failed by a vote of 9-8-0. A motion was made to accept a substantive change. The motion passed by a vote of 17-0-0. Negatives by Carassquillo, Wood and Chrzanowski were withdrawn.

8.1.2 Submittals—Comply with 4.1.2 and unless otherwise specified, the following requirements submit a

O- Specify if thermal control plan is not required. O- Specify if the thermal control plan shall have


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thermal control plan for each mass concrete placement. Unless otherwise specified or permitted in Contract Documents, the thermal control plan shall include the following items:

• the concrete mixture proportions • the calculated or measured adiabatic temperature

rise of the concrete; • an upper limit for the concrete temperature at the

time of placement; • a description of specific measures and

equipment that will be used to ensure the maximum temperature in the placement will not exceed the specified maximum temperature limit;

• the calculated maximum temperature in the placement based on the expected conditions at the time of placement and the use of the proposed measures to control temperatures;

• a description of specific measures and equipment that will be used to ensure the temperature difference will not exceed the specified temperature difference limit;

• the calculated maximum temperature difference in the placement based on the expected conditions at the time of placement and the use of the proposed measures to control temperature differences;

• a description of equipment and procedures that will be used to monitor and log temperatures and temperature differences;

• a drawing showing locations for temperature sensors in the placement;

• a description of the format and frequency of providing measured temperature data to Owner’s Representative;

• a description of measures to address and reduce excessive temperatures and temperature differences, if they occur;

• a description of the curing procedures, including materials and methods, and the duration of curing;

• a description of formwork removal procedures to ensure that temperature difference at the temporarily exposed surface will not exceed the temperature difference limit, and how curing will be maintained.

If the concrete design mixture is changed, the thermal control plan must be updated.

requirements other than listed. A thermal control plan may address a single placement, or a series of similar placements that use the same concrete mixture. S- Thermal control plan. A thermal control plan may address a single placement, or a series of similar placements that use the same concrete mix design. If the concrete mix design is changed, the thermal control plan must be updated. S- Request for alternative items for thermal control plan. S Documentation and test data on cementitious material, aggregates, admixtures, and water. If the Contractor deems it necessary to use a retarding, accelerating, or other admixture in mass concrete, review manufacturer’s data on the admixture and the Contractor’s test results on the admixture with the other project materials.

13.3 LB 08-02, Item 1, Ref 7. Negatives by Ardahl and Chrzanowski. Chrzanowski negative was withdrawn. A motion was made to find Ardahl non persuasive because the submittal is addressed in section 4. The motion passed by a vote of 17-0-0.

13.4 LB 08-02, Item 2, Ref 14. Negatives by Carino, Chrzanowski, Lee and Lobo. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 18-0-0.

8.2.1.2.a Do not use calcium chloride or other O- Specify if accelerating admixtures shall be


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accelerating admixtures, unless specifically otherwise specified or permitted.

permitted, provided that the thermal control plan adequately demonstrates that the specified maximum temperature and temperature difference limits will not be exceeded. Chloride containing accelerators are generally not allowed in reinforced concrete. S- Request to use an accelerating admixture, with justification provided in the thermal control plan. As a general rule, accelerating admixtures should not be used in mass concrete because they contributed to early undesirable heat development. On rare occasions, such as when early formwork removal is critical, accelerating admixtures may be needed to accelerate strength development in reinforced mass concrete during winter conditions. Calcium chloride, if used, should not be permitted in excess of 1% by weight of cement. The Architect/Engineer must accept the use of any accelerating admixture.

13.5 LB 08-02, Item 2, Ref 15. Negatives by Ardahl and Lee. A motion was made to find the negative voters non persuasive because in most placements, retarders do not significantly affect the maximum temperature and temperature difference in the concrete. The motion passed by a vote of 18-0-0.

13.6 LB 08-02, Item 2, Ref 17. Negatives by Ardahl, Carino, Chrzanowski, Hanskat, Lobo and Wood. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change by deleting all of Section 8.2.2 and subsections. The motion passed by a vote of 18-0-0.

14 The Committee addressed resolutions to items on the section on formwork on Letter Ballot 06-01

14.1 LB 06-01 Item 2, Ref 35. Negative by Carino. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 17-0-0.

2.2.2.5.d Unless otherwise permitted, provide construction, expansion and contraction joints where indicated on the Contract Documents. Submit the alternative locations and details of construction and contraction joints if different differing from those indicated on the Contract Documents.

S Alternative locations and details for formed construction and contraction joints. S Proposed alternative joint locations.

14.2 LB 06-01, Item 2, Ref 21. Carino negative. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The changes included revisions to 5.3.3.3 and 5.3.3.4 regarding form finishes. The motion passed by a vote of 23-0-0.

2.2.1.1 Form-facing materials –Unless otherwise specified or permitted, materials for form faces in contact with concrete shall be lumber, plywood, tempered concrete-form-grade hardboard, metal, plastic, or paper that create the specified appearance and texture of concrete surface.

S – Other form-facing materials. O – Specify specific form-facing materials.

5.3.3.3 As-cast formed finishes – Use form-facing materials meeting 2.2.1.1. Produce as-cast formed finishes in accordance with Contract Documents and 5.3.3.3.a through 5.3.3.3.d:

5.3.3.3.a Surface Finish-1.0 (SF-1.0):


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• No formwork facing material is specified. • Patch voids larger than 1-1/2 in. wide by or 1/2

in. deep. • Remove projections larger than 1 in. • Tie holes need not be patched. • Surface tolerance Class D as specified in ACI

117. • Mock-up not required.

5.3.3.3.b Surface Finish-2.0 (SF-2.0) : • Patch voids larger than 3/4 in. wide or 1/2 in.

deep. • Remove projections larger than 1/4 in. • Patch tie holes. • Surface tolerance Class B as specified in ACI

117. • Provide mock-up of concrete surface appearance

and texture.

5.3.3.3.c Surface Finish-3.0 (SF-3.0) : • Patch voids larger than 3/4 in. wide or 1/2 in.

deep. • Remove projections larger than 1/8 in. • Patch tie holes. • Surface tolerance Class A as specified in ACI

117. • Provide mock-up of concrete surface appearance

and texture.

5.3.3.4 Unspecified as-cast finishes – Unless otherwise specified in Contract Documents for a concrete surface, apply the following finishes:

• Surface Finish-1.0 (SF-1.0) on concrete surfaces not exposed to view.

• Surface Finish-2.0 (SF-2.0) on concrete surfaces exposed to view.

O-Specify location and type of alternative as-cast formed finish.

5.3.3.5 Architectural finishes—Produce architectural finishes including special textured finishes, exposed-aggregate finish, and aggregate transfer finish in accordance with Section 6.

15 The Committee continued resolutions to items on the section on precast concrete on Letter Ballot 08-01

15.1 LB 08-01, Item 9, Ref 97. Negatives by Carreira, Chrzanowski, Hanskat, Hover, Lee and Prenger. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 21-0-1.

13.2.12.10.a. Exposed to damp or continuously wet environmental conditions – Limit concrete temperature to 150° F. If this is not practicable, use a concrete mixture that can tolerate a higher initial temperature without an adverse effect on long term durability. A maximum concrete temperature of 170° F is acceptable if one of the following measures is permitted: • Use of ASTM C 150 Type V portland cement with

Blaine fineness less than 400 m2/kg, or ASTM C 595 Type IP blended cement with at least 20% Class F fly ash, or ASTM C 595 Type IS blended cement with at least 35% slag cement.

• Use of cement with 1 day mortar strength (ASTM C109/C 109M) less than 2900 psi.

O Indicate which combination of cementitious materials will be acceptable. Select the combinations that will be suitable for the expected service conditions. S – Mixture proportions to increase maximum concrete temperature to 170oF.


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• Replacement of portland cement with 20 to 35% (by mass) of fly ash meeting ASTM C618 Class F.

• Replacement of portland cement with 35 to 50% (by mass) of slag cement meeting ASTM C 989.

• Replacement of 35 to 50% (by mass) of portland cement with a combination of ASTM C618 Class F fly ash (maximum 35%), ASTM C 989 slag cement, and ASTM C1240 silica fume (maximum 10%).

• Replacement of 35 to 50% (by mass) of portland cement with a combination of ASTM C618 Class C fly ash (maximum 35%) and at least 6% ASTM C 1240 silica fume (maximum 10%), ultra-fine fly ash, or ASTM C 618 Class N metakaolin.

• Replacement of 10% (by mass) of portland cement with a metakaolin meeting ASTM C 618 Class N.

15.2 LB 08-01, Item 5, Ref 62. Negatives by Hanskat, Carino and Lee. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 28-0-0.

13.2.7.2 Non-shrink Grout: When specified, use premixed, prepackaged non-shrink grout complying with ASTM C 1107, Grade A for dry pack applications and Grades B and C for flowable applications. Unless otherwise specified, ferrous grouts shall not be used. When required, submit field installation procedures

O Specify if non-shrink grout is required. For critical installations, specify that field installation procedures should be submitted. Specify if ferrous grouts can be used. S Field installation procedures, when required

16 The Committee address resolutions to items on Section 4 on Letter Ballot 07-04

16.1 LB 07-04, Item 10, Ref 12. Negatives from Ardahl, Carino, and Carrasquillo. A motion was made to find Carino non persuasive because the contractor needs to know the definition of the exposure classes. The motion failed by a vote of 5-20-0. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 22-1-0, with McCall voting negative. A motion was made to find McCall non persuasive because the options are equivalent unless the A/E feels otherwise. The motion passed by a vote of 22-2-0. Ardahl negative was withdrawn. A motion was made to find Carrasquillo non persuasive because another footnote permits service record. The motion passed by a vote of 18-0-1. The 2nd and 3rd parts of Carino’s negative were withdrawn for consideration as new business.

4.2.2.9.a Sulfate Resistance – Unless otherwise specified, pProvide concrete meeting the requirements of Table 4.2.2.9.a-2, based on exposure class for exposure to water soluble sulfates defined in Table 4.2.2.9.a-1 for those portions of the structure designated as requiring sulfate resistance in the Contract Documents. Submit documentation verifying compliance with specified requirements.

M Designate in Contract Documents the exposure class for portions of the structure requiring concrete resistant to sulfate attack. Consult Table 4.2.2.9.a-1 for designating the exposure class. Refer to ACI 318R-08 for description of exposure classes additional guidance. Criteria for evaluating effectiveness of cementitious materials alternate to those in Table 4.2.2.9.a-2 are provided in Table 4.2.2.9.a-3. Alternatively, consider accepting concrete mixtures that have shown a service record in excess of eight years in exposure at least as severe as that of the proposed structure. O Specify alternative mixture requirements for sulfate resistance. S Documentation indicating compliance with the specified requirements for sulfate resistance in accordance with Table 4.2.2.9.a-2. Alternative documentation may include test results on the


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cementitious material to be used in the proposed concrete mixture in accordance with criteria in Table 4.2.2.9.a-3 or evidence of adequate sulfate resistance of at least 8-year old existing structures in exposures at least as severe as the proposed structure. The level of sulfate ions in the soil or water of the existing structure should be comparable to the exposure of the proposed structure as provided by the Architect/Engineer.

Table 4.2.2.9a-1 Exposure Category S – Sulfates exposure

Class Description Water-soluble sulfate (SO4) in soil, percent by weight Sulfate (SO4) in water, ppm

S0 Not applicable SO4 < 0.10 SO4 < 150

S1 Moderate 0.10 ≤ SO4 < 0.20 150 ≤ SO4 < 1500 Seawater

S2 Severe 0.20 ≤ SO4 ≤ 2.00 1500 ≤ SO4 ≤ 10,000

S3 Very severe SO4 > 2.00 SO4 > 10,000

Table 4.2.2.9a-2 For Exposure Category S – Sulfate exposure

Exposure Class

Max w/cm

Min 'cf

psi

Required Cementitious Materials* - Types Additional Requirements ASTM C

150 ASTM C 595 ASTM C 1157

S0 - - - - - -

S1 0.50 4000 II**, *** IP(MS), IS(<70)(MS) MS -

S2 0.45 4500 V*** IP(HS), IS(<70)(HS) HS No calcium chloride

admixtures

S3 0.45 4500

V + pozzolan or

slag cement****

IP(HS) or IS(<70)(HS) + pozzolan

or slag cement****

HS + pozzolan or slag cement

****

No calcium chloride admixtures

* Alternative combinations of cementitious materials to those listed in Table 4.2.2.9.a-2 shall be permitted when tested for sulfate resistance and meeting the criteria in Table 4.2.2.9.a-3 ** For seawater exposure, other types of portland cements with tricalcium aluminate (C3A) contents up to 10 percent are permitted if the water-cementitious material ratio does not exceed 0.40. *** Other available types of cement such as Type III or Type I are permitted in Exposure Classes S1 or S2 if the C3A contents are less than 8 or 5 percent, respectively. **** The amount of the specific source of the pozzolan or slag to be used shall not be less than the amount that has been determined by test or service record to improve sulfate resistance when used in concrete containing Type V cement. Alternately, the amount of the specific source of the pozzolan or slag to be used shall not be less than the amount tested in accordance with ASTM C 1012 and meeting the requirements of Table 4.2.2.9.a-3.

Table 4.2.2.7a-1—Requirements for Establishing Suitability of Cementitious Materials Combinations Exposed to Water-Soluble Sulfate.

Exposure Class Maximum Expansion when tested using ASTM C 1012 At 6 months At 12 months At 18 months

S1 0.10% S2 0.05% 0.10% * S3 0.10%

* The 12 month expansion limit applies only when the measure expansion exceeds the 6 month maximum expansion limit.


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16.2 LB 07-04, Item 10, Ref 13. Negatives by Carino and Neff. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 17-0-2.

4.2.2.9.b Freezing and e Thawing -Unless otherwise specified, pProvide concrete meeting the requirements of Table 4.2.2.9.b-2 based on exposure class for freezing and thawing exposure defined in Contract Documents. Table 4.2.2.9.b-1 for those portions of the structure designated as requiring resistance to freezing and thawing in. Submit documentation verifying compliance with specified requirements.

M Designate in Contract Documents the exposure class for portions of the structure requiring resistance to freezing and thawing. Consult Table 4.2.2.9.b-1 for designating exposure class. Refer to ACI 318R-08 for additional guidance. S Documentation verifying compliance with

specified requirements for freezing and thawing exposure. thaw in accordance with Table 4.2.2.9.b-2. O Specify alternative mixture requirements for freezing and thawing resistance.

Table 4.2.2.9.b-1. Exposure Category F – Freezing and thawing Exposure

Class Description Condition

F0 Not Applicable Concrete not exposed to freezing and thawing cycles

F1 Moderate Concrete exposed to freezing and thawing cycles and occasional exposure to moisture

F2 Severe Concrete exposed to freezing and thawing cycles and in continuous contact with moisture

F3 Very Severe Concrete exposed to freezing and thawing cycles that will be in continuous contact with moisture and exposure to deicing chemicals

Table 4.2.2.9.b-2 For Exposure Category F – Freezing and thawing exposure Exposure

Class Max w/cm

Min ƒ´c, psi Entrained Air Additional Requirements

F0 - - -

F1 0.45 4500 Table 4.2.2.9.b-1 -

F2 0.45 4500 Table 4.2.2.9.b-1 -

F3 0.45 4500 Table 4.2.2.9.b-1 Table 4.2.2.9.b-2 Table 4.2.2.9.b-1 Total air content for concrete exposed to cycles of freezing and

thawing

* Tolerance on air content as delivered shall be ± 1.5 %. ** For f’c > 5000 psi reducing air content by 1.0 percent is permitted. *** See ASTM C 33 for tolerance on oversize for various nominal maximum size designations. **** These air contents apply to total mixture. When testing these concretes

Nominal maximum Aggregate size, in.***

Air Content (%)*, ***

Exposure Class F2 and F3

Exposure Class F1

3/8 7.5 6 1/2 7 5.5 3/4 6 5 1 6 4.5

1-1/2 5.5 4.5 2**** 5 4 3**** 4.5 3.5


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however, aggregate particles larger than 1-1/2 in. are removed by sieving and air content is measured on the sieved fraction (tolerance on air content as delivered applies to this value). Air content of total mixture is computed from value measured on the sieved fraction passing the 1-1/2 in. sieve in accordance with ASTM C 231.

Table 4.2.2.9.b-2 Requirements for concrete subject to Exposure Class F3

Cementitious materials Maximum percent of total cementitious materials by weight*, **

Fly ash or other pozzolans conforming to ASTM C 618 25

Slag cement conforming to ASTM C 989 50

Silica fume conforming to ASTM C 1240 10

Total of fly ash or other pozzolans, slag, and silica fume 50***

Total of fly ash or other pozzolans and silica fume 35***

* The total cementitious material also includes ASTM C 150, C 595, and C 1157 cement. ** The maximum percentatges above shall include

a. Fly ash or other pozzolans present in Type IP, blended cement, ASTM C 595, or ASTM C 1157;

b. Slag used in the manufacture of a IS blended cement, ASTM C 595, or ASTM C 1157;

c. Silica fume, ASTM C 1240, present in a blended cement. *** Fly ash or other pozzolans and silica fume shall constitute no more than 25 and 10 percent, respectively, of the total weight of the cementitious materials.

16.3 LB 07-04, Item 10, Ref 14. Carino negative. There was no motion to find the negative non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 23-0-0. Other negatives by Carino, Neff and Wood were withdrawn. A motion was made to find Chrzanowski non persuasive because the exposure classes are as defined in ACI 318. The motion passed by a vote of 19-0-0.

4.2.2.9.c Low Permeability- Unless otherwise specified, pProvide concrete meeting the requirements of Table 4.2.2.9.c-2 based on exposure class for structural members in contact with water requiring low permeability defined in Table 4.2.2.9.c-1 for those portions of the structure designated as requiring low permeability in the Contract Documents. Submit documentation verifying compliance with specified requirements.

M Designate in Contract Documents the exposure class for portions of the structure requiring low permeability when in contact with water. Consult Table 4.2.2.9.c-1 for designating exposure class. Refer to ACI 318R-08 for description of exposure classes. S Documentation verifying compliance with

specified requirements for low permeability in accordance with Table 4.2.2.9.c-1. O Specify alternative requirements for low

permeability.

Table 4.2.2.9.c-1 Exposure Category P – In contact with water requiring low permeability concrete

Class Description Condition

P0 Not applicable Concrete where low permeability to water is not required

P1 Required Concrete required to have low permeability to water


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Table 4.2.2.9.c-2 For Exposure category P – In contact with water requiring low permeability concrete

Exposure Class

Max w/cm

Min 'cf

psi Additional Minimum Requirements

P0 - - -

P1 0.50 4000 -

16.4 LB 07-04, Item 10, Ref 15, negatives by Lee, Carino and Neff. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 21-0-0. Lobo negative was withdrawn

4.2.2.9.d Corrosion Protection of Reinforcement - Unless otherwise specified pProvide concrete meeting the requirements of Table 4.2.2.9.d-2 for conditions requiring corrosion protection of reinforcement defined in Table 4.2.2.9.d-1 for those portions of the structure designated as requiring corrosion protection of reinforcement in the Contract Documents. Submit documentation verifying compliance with specified requirements.

M Designate in Contract Documents the exposure class for portions of the structure requiring corrosion protection of reinforcement. Consult Table 4.2.2.9.d-1 for designating exposure class. Refer to ACI 318R-08 for additional guidance. Additional information on the effects of chlorides on corrosion of reinforcing steel is given in ACI 201.2R and ACI 222R. Test procedures must conform to those given in ASTM C 1218/C 1218M. An initial evaluation can be obtained by testing individual concrete ingredients for total chloride content. If total chloride-ion content, calculated on the basis of concrete proportions, exceeds that permitted in Table 4.2.2.9.d-2, it may be necessary to test samples of hardened concrete for water-soluble chloride-ion content as described in ASTM C 1218/C 1218M. Some of the total chloride ions present in the ingredients will either be insoluble or will react with the cement during hydration and become insoluble under the test procedure described. When concrete is tested for water-soluble

chloride-ion content, the tests should be made at an age of 28 to 42 days. The limits in Table 4.2.2.6 are to be applied to chlorides contributed from the concrete ingredients, not those from the environment surrounding the concrete. When epoxy- or zinc-coated bars are used, the limits in Table 4.2.2.9.d-2 may be more restrictive than necessary. Specify if higher limits are allowed. See the references given in the Mandatory Requirements Checklist for 4.2.2.9.d. O Specify alternative mixture requirements for corrosion protection of reinforcement. S Documentation verifying compliance with specified requirements for corrosion resistance. in accordance with Table 4.2.2.9.d-2.


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Table 4.2.2.9.d-1 Exposure Category C – Conditions requiring corrosion protection of reinforcement

Class Description Exposure

C0 Not applicable Concrete that will be dry or protected from moisture in service

C1 Moderate Concrete exposed to moisture but not to external source of chlorides in service

C2 Severe Concrete exposed to moisture and an external source of chlorides in service – from deicing chemicals, salt, brackish water, seawater, or spray from these sources

Water-soluble chloride ion content that is contributed from the ingredients including water, aggregates, cementitious materials and admixtures shall be determined on the concrete mixture by ASTM C 1218 at age between 28 and 42 days

Table 4.2.2.9.d-2 For Exposure Category C – Conditions requiring corrosion protection of reinforcement

Exposure Class

Max w/cm

Min 'cf

psi

Max water-soluble chloride ion (Cl-) content in concrete, percent by weight of

cement

Additional Minimum Requirement

Reinforced Concrete

C0 - - 1.00 -

C1 - - 0.30 -

C2 0.40 5000 0.15 Cover

Prestressed Concrete

C0 - - 0.06 -

C1 - - 0.06 -

C2 0.40 5000 0.06 Cover

16.5 LB 07-04, Item 10, Ref 17, negative by Carrasquillo. A motion was made to find the negative voter non persuasive because this conforms to the requirements of ACI 318. The motion passed by a vote of 17-0-0. Negative by Lee. A motion was made to find the negative voter non persuasive because the difference in strengths are not significant. The motion passed by a vote of 18-0-0.

16.6 LB 07-04, Item 1, Ref 1, negative by Carino, Lee, Chrzanowski and Wilson. Wilson withdrew on portions of negative. There was no motion to find the negative voters non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 22-0-0.

4.2.1.1 Cementitious materials—Use ASTM C 150 Type I or Type II cement. Alternatively use unless one or a combination of the cementitious materials given in 4.2.1.1.a through 4.2.1.1.f when are specified or permitted or when required to meet the durability criteria of 4.2.2.9.

O Specify the other standards that the cementitious material may be required or permitted to conform to if cement other than ASTM C 150 Type I or Type II is required or permitted. Specify if ASTM C 150 cement with ASTM C 618 pozzolanic materials, ASTM C 989 slag cement, or ASTM C 1240 silica fume, is required. Specify the class of pozzolan or grade of slag that is required. Specify if ASTM C 595 blended hydraulic cement or C 1157 hydraulic cement are required or permitted. Specify the type of ASTM C 595 blended cement or C 1157 hydraulic cement that is required. When one or a combination of cementitious materials given in 4.2.1.1.a through 4.2.1.1.f are used in structures that will be subjected to deicing chemicals, verify compliance of the concrete with Section 4.2.2.9.d.


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Use ACI 318 and 225R to determine what will be acceptable for the project conditions. ASTM C 1157 is a performance specification for

hydraulic cement. Requirements for physical properties of the cement are specified in ASTM C 1157; however, there are no restrictions on the composition of the cement or its constituents. When using ASTM C 1157, the Architect/Engineer should consider whether any additional limits on physical properties or constituents should be specified. If it is suspected that concrete will be exposed to sulfates in service, evaluate the water-soluble sulfates in the soil and groundwater. Use the criteria in Section 4.2.2.9.a and Table 4.2.2.9.a-2 to determine the type of cement to use. Use the criteria of ACI 318, Section 4.3.1 and Table 4.3.1, to determine the cement type to use. Use any of the cements in ACI 318, Table 4.3.1 for concrete exposed to sea water. Verify the availability of the cement specified. Do not use ASTM C 595, Type S and SA. Specify if less than 15% fly ash is permitted. In some instances, using less than 15% fly ash can increase the concrete’s susceptibility to excessive expansions caused by alkali-silica reactivity (ASR). If a smaller percentage of fly ash is proposed for use, the proposed project mixture of fly ash and portland cement from the same source should be tested and compared to a control mixture using only the portland cement in accordance with ASTM C 441. The project mixture should be considered acceptable, provided the average length increase of the project mixture does not exceed that of the control mixture. For projects where expansions due to ASR may be critical, consider requiring the test comparison at some frequency during the Work, such as every three months. If reactive aggregates are available and may be used, specify the use of natural pozzolan, fly ash, slag, or silica fume in an amount shown to be effective in mitigating harmful expansions due to alkali-silica reactivity. Alternatively, specify a low-alkali cement be used as described in the Optional Requirements Checklist for 4.2.1.2. S Requests to use cementitious materials other than ASTM C 150 Type I or Type II.

16.7 LB 07-04, Item 2, Ref 2. Wilson negative was withdrawn.

16.8 LB 07-04, Item 3. Ardahl negative. A motion was made to find Ardahl non persuasive because ASTM C1602 provides procedures to qualify non-potable water for use as mixing water. The motion failed by a vote of 5-11-2. The item was withdrawn and the language reverts to original.

16.9 LB 07-04, Item 4. Carrasquillo negative. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 21-0-0. A motion was made to find Whisonant non persuasive because the default is still the point of delivery. The motion passed by a vote of 20-0-1. The negative by Wood was withdrawn.


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4.2.2.4 Air content—Unless otherwise specified, concrete shall be air-entrained and the air content at the point of delivery shall conform to the requirements of Table 4.2.2.4 for severe exposure. For specified compressive strengths above 5000 psi, the air contents indicated in Table 4.2.2.4 may be reduced by 1%. Measure air content in accordance with either ASTM C 138, C 173, or C 231 Unless otherwise specified, concrete shall be air entrained in accordance with section 4.2.2.2.9.b. Unless otherwise specified, measure air content at point of delivery in accordance with Measure air content in accordance with ASTM C 173; or ASTM C 231.

O Specify if concrete is not required to be air-entrained. Air content of normalweight concrete used in Intentionally entrained air should not be incorporated in normal weight concrete slabs that are not subjected to freeze thaw and that require a dense, polished, machine-troweled surface should not exceed 3% and should not contain air entraining admixture. For normalweight concrete used in slabs that are not subjected to cycles of freezing and thawing and that require a dense, machine-troweled surface, the air content should not exceed 3 % (see ACI 302.1R) and air entraining admixtures should not be used. ACI 302 recommends that the air content of concrete for such applications should not exceed 3%. All concrete, regardless of whether air entraining admixtures are used, shall be tested for air content Such concrete shall be protected from cycles of freezing and thawing during construction. Refer to ACI 302.1R for further guidance. For air-entrained concrete for other than severe

exposure, Specify the type of exposure as indicated in Table 4.2.2.4. cementitious material content. To improve strength, air contents lower than those needed for durability can be used. This exposure includes indoor or outdoor service. Moderate exposure—Service in a climate where

freezing is expected, but where the concrete will not be continually exposed to moisture or free water for long periods before freezing and will not be exposed to deicing agents, other aggressive agents, or other aggressive chemicals. Examples include exterior beams, columns, walls, girders, and slabs that are not in contact with wet soil and are located so that they will not receive direct application of deicing salts. Severe exposure—Concrete that is exposed to

deicing chemicals or other aggressive agents or that may become highly saturated by continual contact with moisture or free water before freezing. Examples include parking structures, pavements, bridge decks, curbs, gutters, sidewalks, canal linings, and exterior water tanks or sumps. Specify if a particular ASTM test method (ASTM

C 231, C 138, or C 173) is required for measuring air content. For the same reasons as described in the Optional

Requirements to 4.2.2.2, i O It may be necessary to specify that air content

be measured at the point of placement to account for loss of air content during pumping. Once the loss of air content during pumping is established, acceptance limits at the point of placement discharge can be determined. Specify if a particular ASTM test method (ASTM C 231 or C 173) is required for measuring air content.


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16.10 LB 07-04, Item 11, Ref 18. Chrzanowski negative. There was no motion to find the negative voter non persuasive. A motion was made to accept a substantive change. The motion passed by a vote of 20-1-0 with Ardahl voting negative. A motion was made to find Ardahl non persuasive because evaluating a range of trial batches will result in batches outside the range of the requirements for durability. The motion passed by a vote of 18-1-1.

4.2.3.4.b • Make at least three trial mixtures for each class of

concrete with a range of proportions that will produce a range of compressive strengths that will encompass f’cr and satisfy the durability requirements of Section 4.2.2.9. complying with 4.2.2. Each trial mixture shall have a different cementitious material content. Select water-cementitious material ratios that will produce a range of compressive strengths encompassing f′cr. For concrete made with more than one type of cementitious material, the concrete supplier must establish not only the water-cementitious materials ratio but also the relative proportions of the cementitious materials and admixtures, if any, that will produce the required average compressive strength and satisfy durability requirements of section 4.2.2.9.

• For each trial mixture, make and cure three compressive strength cylinders for each test age in accordance with ASTM C 192/C 192M. Test for compressive strength in accordance with ASTM C 39/C 39M at 28 days or at the test age specified for f’c designated in Contract Documents.

17 There being no further business, the meeting was adjourned at 6:45 p.m.

Respectfully Submitted

Colin Lobo Secretary, ACI 301