ACI 318 Sub A – General Concrete and Construction

ACI 318 Sub A – General Concrete and Construction [ACI 318 Chapters 1, 2, 3 (excluding 3.5), 4, 5, 6, and 22

Reorganized Chapters 5, 22, and 23]

Dallas Meeting Tuesday, 20 March 2011, 1:30 PM to 6:00 PM, Meeting Room Moreno B

DRAFT MINUTES 1. Call to order at 1:30 pm. 2. Introductions and Membership changes. Sign up sheet is attached.

Brian Gerber of ICC-ES has joined Sub A

3. Approval of Agenda. Approved as presented. 4. Approval of Minutes: Cincinnati Meeting, 18 October 2011. Approved as presented.

5. Old Business: Please see the following Table for the agenda for the bulk of today’s meeting. Note that the experiment allotting times for individual segments of the agenda failed miserably!

Item Description Responsible 5.1 General update from Steering Committee meeting

The schedule for completing the code and commentary was discussed. It looks like we are back to looking at a 2014 document with minimal new business items included. Sub A will work to include the most critical changes to our chapters.

Terry

5.2 Resolution of issues from 318 LB of CA 026 1. CA 026 ballot results were reviewed and minor changes were made. The final version was approved by Sub A by a vote of 12 affirmative and 1 not present. 2. CA026 was presented on the floor of the 318 meeting on Wednesday. All negatives were either withdrawn or found non persuasive. There were additional changes made on the floor. CA 026 was approved by 318. A copy of this item, as approved by 318, is attached. The final responses as approved by 318 are also attached. 3. The changes resulting from CA 026 were incorporated into Chapter 22, and this chapter with commentary is on the 6 April 318 LB.

Terry

5.3a Chapter 5, Resolution of negatives and significant comments from Sub A ballot on Commentary 1. The proposed responses to the ballot on the commentary of Chapter 5 were discussed. Changes were made to satisfy the subcommittee. The final version was approved by Sub A by a vote of 12 affirmative and 1 not present. A copy of the final approved responses is attached. Note that a number of new business items were developed during this review. 2. The responses have been incorporated into the chapter. The current target is to have Chapter 5 with commentary on the 6 May 318 LB.

Tony

5.3b Chapter 5, Recommendations for top 3 new business items Not discussed because of a lack of time.

Tony

5.4a Chapter 22, Resolution of negatives and significant comments from Sub A ballot on Commentary 1. The proposed responses to the ballot on the commentary of Chapter 22 were discussed. Changes were made to satisfy the subcommittee. The final version was approved by Sub A by a vote of 10 affirmative and 3 not present. A copy of the final approved responses is attached. 2. The responses have been incorporated into the chapter. Chapter 22 with commentary is on the 6 April 318 LB.

Nick

5.4b Chapter 22, Recommendations for top 3 new business items Not discussed because of a lack of time.

Nick

5.5 Chapter 23, Comments from presentation at Steering Committee meeting

1. The overall organization of Chapter 23, as approved by Sub A in Denver, was accepted by the Steering Committee. 2. Subs B and G agreed to take responsibility for their respective sections of the chapter. They will also look at t he section on embedments to determine who should be responsible for this material. 3. It was agreed to keep a separate section on submittals as a part of the chapter. 4. All subs agreed to look at the “orphans” at the end of the chapter to determine where they should be located in the code. 5. Since the meeting, a copy of Chapter 23 as balloted by Sub A was sent to all of the subs. Additionally, the Sub A ballot comments were provided for use by the other subs. 6. A target date of the May 318 LB was established for a 318 ballot on this chapter.

Terry

5.6 Chapter 23, Resolution of negatives and significant comments from Sub A ballot on Commentary 1. Overall direction from the subcommittee was defined. 2. The chapter is to be a listing of items that are relevant to building officials and contractors. No separation of items directed at one or the other. 3. There can be pointers as necessary to other chapter where information required in the construction documents may be located. 4. The Chapter 23 Task Group will work on addressing the comments from the Sub A ballot.

Colin

5.7 CA 104, Resolution of Negatives from last ballot Not discussed because of a lack of time. Further actions on this item will be handled electronically.

Doug

5.8 Formation of Task Group to review ASTM C 1600 cements The Task Group will be Kosmatka, Weiss, and Barth. Jason will be the chair. ASTM C 1600 will be made available to the subcommittee for review. The goal of the task group is to make a recommendation s to whether C1600 should be added to the Code. If the recommendation is to add this standard, are there any restrictions that need to be added?

Terry

5.9. Summary of all CA items. An updated list of all CA items was sent out after the Cincinnati meeting. This list showed 17 active items. Many of these active items have been referred to the Chapter 5 and Chapter 22 Task Groups to be included in the list of potential new business. An updated list after the Dallas meeting is attached. There are currently 17 open items. 5.10. Code reorganization. 5.10.1 Task Groups for Code Reorganization. Following are the current Task Groups. Note changes below to reflect that the work on the original Chapter 23 has been completed. Chapter 5, Material Properties and Durability. Tony, CH, Fred, Doug, Jason Chapter 22, Concrete Materials and Quality Assurance, Nick, CH, Ken B., Brian Chapter 23, Construction Documents. Colin, CH, Steve, Ken H., Harry, Florian, Dean 5.10.2 Current Status: See the actions in the Table on page 2. The following items will not be discussed during the Dallas meeting. 5.11. Use of 4 x 8 inch cylinders. Rachel Detwiler sent Sub A a copy of a paper that she has prepared. Mike Bartlett has also provided comments on this paper. Colin Lobo also provided additional information on this topic. The committee agreed that we would like to see data from additional labs before making any changes to the requirement for testing three 4 x 8 in. cylinders. Harry Gleich reported that the precast industry has converted to testing only two cylinders. Colin Lobo will forward additional test data. The committee agreed to reopen this item. Steve Kosmatka and Colin Lobo were appointed to summarize current data and to prepare a new b allot item for consideration. This item is assigned CA 105. Steve and Colin will update references in CA 105 and send for a Sub A ballot. Status? 5.12. Performance specifications and implications for 318. Topic remains open for possible action during this code cycle. 5.13. Adding alkali-silica reactivity (ASR) to the Code. Of all of the major durability issues with concrete, only ASR is not addressed in the Code. After discussion, a Task Group of Folliard, Hooton, and Fiorato was formed to review this issue and make a recommendation to the committee during the meeting in New Orleans. In Chicago, Tony reported that ASTM C09 is preparing a specification for dealing with ASR. Sub A agreed to put any action on hold until that document is completed. It was agreed that it is still premature for Sub A to take any action here. This item will remain on the agenda until action is taken. 5.14. Determining Lambda. Carino had the following comment on Sub A Ballot A02-09:

I have some questions about the splitting tensile strength. First, fct is defined as the average splitting tensile strength, so this is not a function of f'c, but a function of the average compressive strength of the concrete. So it is not correct to say that fct is 6.7 sqrt(f'c). Second, I'd like an explanation of how an engineer would determine lambda for the second alternative. The code language is not clear. I think the fct in the equation should be measured average splitting tensile strength. Maybe Fred or Ken can explain to us how the equation in 8.6.1 is supposed to be used to choose lambda.

This issue is being addressed as a CA items that will be sent out with the ballot on Chapter 5 commentary. The ballot item will clean up the method of calculating lambda. Further work remains on lambda versus unit weight issues. Also, the question of whether the method of calculating lambda is actually used by designers has bee raised as new business.

5.15. Sulfate resistance: The following email was sent to Cathy French. Colin Lobo responded as shown.

I hope your sabbatical is going well. I had a question for you when > you have a minute. On our wind farm projects in some parts of the > country we are running into situations where we have severe sulfate > exposures and it seems that I am continually at odds with local > concrete suppliers over the interpretation of the sulfate resistance > portions of chapter 4 of ACI 318. Is this one of your fields of > expertise or can you recommend someone I could talk to so I can make > sure I am doing the right thing? > > > > The issue that I keep running into is that, the way I read section > 4.3, for severe sulfate exposures, type V cement is required. Type I > or II cement with the addition of class F fly ash can be used if the > mixture meets the requirements of section 4.5 when tested according to > ASTM C1012. The problem is that the test takes 6 months or a year to > run and I have yet to run into a concrete supplier who has run it on > any of their mixes. The suppliers that I talk to want to offer me a > test result from ASTM C452 but I have found multiple references in the > literature to the fact that this test is not accurate for mixes > containing cement blended with pozzolans. I have continued to insist > that the C1012 test be run if anything is to be substituted for the > type V cement but I seem to be the only engineer that these suppliers > are running into that is requiring them to do this. Colin Lobo: I will attempt a response. The sulfate provisions in the code are not ideal for compliance in practice. In the footnote to table 4.3.1 "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 service record..." This note permits the LDP to use customary practice on mix composition in lieu of test. It is realized the test duration is too long for mix submittals. It is unlikely that concrete suppliers will have C1012 data. It is more likely that blended cements by C595 or C1157 will have data in their certifications, but S3 requires additional SCM. In CA for instance the use of 25% fly ash in addition to a sulfate resistant cement has been considered adequate for severe sulfate conditions. I think it is accepted by CALTRANS. I am not sure of the area of your projects, but slag as an SCM might be an option too. Slag has been entering the CA market more recently and these suppliers (as with the fly ash people) might have C1012 data but it wont be with the specific cement for the project. What is important in the cement would be the C3A used in the test relative to that used on the project. If that on the project is equal to or less than that used in the test, it should be OK.

ASTM C 452 is not an appropriate test - it is an optional test to qualify Portland cements for sulfate resistance only. You might consult with Eric Tolles who is a code official for the city of Irvine in CA (if that's where you are operating). Eric is on 318 and aware of these provisions.

Does Sub A need to take action here? This item was not discussed in New Orleans, Chicago, Pittsburgh, Tampa, or Denver because of a lack of time. Status? 6. New Business: Note that the following new business items are listed by title only because we will probably not have time to address them. If time is available or if a topic is of interest to a member, we will address these items. 6.1. Core waiting period. 6.2. Add recycled aggregate to the Code. 6.3. Top bar effects in self-consolidating concrete. 6.4. Fix mixture proportioning flow chart in Commentary. This item is now moot. It will be dropped from the agenda. 6.5. Various new work items resulting from review of Version 1 of the reorganized Code. These items are being incorporated into the possible new work lists as chapters are adopted. 6.6. w/cm versus strength for durability. 6.7. Chloride ion restrictions in concrete containing aluminum embedments. 6.8. Request to add ASTM C 1600 Rapid hardening Hydraulic Cements to the Code. See item 5.8 above. A task group has been formed to look into this issue. 6.9. Inquiry regarding appropriate strength for w/cm for durability. 6.10. Ward Malish issues regarding brackish water. Note: Other than as indicated, these items have been addressed to date because of lack of time. 7. Adjourn

SUMMARY OF SUB A ITEMS -- AFTER DALLAS MEETING

Total Sub A items 48Last CA Number Assigned CA 114

SOURCES Carryover from 2008 Code cycle 16Added from public 2008 comments 11Added during this Code cycle 20

Total 47

RESOLVED Adopted, 2011 Code 6Not adopted, 2011/2014 Code 24Adopted, 2014 Code 1Active items 17

Total 48

ACTIVE ITEMS

NUMBER DESCRIPTION RESPONSIBLE COMMENTS

CA 002 Curing issues, 5.6.4.1 and 5.11. New Chapter 22

Hover 25 Mar 12, email to Hover regarding future of this item.

CA 056 Harmonize chloride limits. New Chapter 5 Weiss On hold, coordinate with ACI 201 and ACI 222

CA 065 Maximum size of aggregate between reinf and forms. New 22.3.2.1

Holland, CH 22 TG

Passed Sub A. To CH 22 TG to consider.

CA 069 Incorporate certified inspectors into the Code. New Chapter 22.

Holland and Carino

Sub A ballot 10-2006, DNP. Holland to update and ballot.

CA 070 Cementitious materials for chlorides. New Chapter 5.

Lobo/Weiss On hold, coordinate with ACI 201 and ACI 222

CA 077 Rewrite Ch 5, construction issues. New Chapter 23.

Hover Sub A ballot A01-2009, DNP, revise and reballot. Will be addressed once CH 23 is available.

CA 088 2008 Code, PC 38, Gustafson 318 ballot comment. Table R.4.3.1, second sentence below table. Delete sentence regarding epoxy and zinc coated bars. New Chapter 5.

Hooton, CH 5 TG Was on Sub A A04-2011, did not pass Sub A. To CH 5 TG to consider.

CA 092 2008 Code, PC 69, Cunningham. 2.2 and 5.6.2.4, add definition of strength test to Ch. 2. New Chapters 2 and 22.

Carino Passed Sub A -- 14 Oct 11 -- to Ch 22 TG for inclusion in new business

CA 093 2008 Code, PC 414, Green. R8.6.1, give justification for interpolation in values of lamda. New Chapter 5.

Bondy/Meyer, CH5 TG

Passed Sub A. To CH 5 TG to consider.

CA 099 Clarify use of term f'c, various locations. New Chaapter 22.

Fiorato Passed Sub A -- 14 Oct 11 -- to Ch 22 TG for inclusion in new business

CA 101 Clarify requirements regarding measuring air. New Chapter 5.

Hover, CH 5 TG Passed Sub A. To CH 5 TG to consider.

CA 103 Add "and roofs" to 6.4.4 (misc Item #3) New Chapter 23

Holland Passed Sub A. Will be addressed once CH 23 is available.

CA 104 Remove Exposure Cat. "Permeability" from Ch. 4; misc edits to Ch. 4 (misc item # 4); includes clarification of Cats C and F. New Chapter 5.

Lobo/Hooton On Sub A ballot A06-2011, did not pass. Discuss in Cincy

CA 105 Number of 4x8 inch cylinders required. New Chapter 22.

Kosmatka Assigned at San Antonio meeting. Waiting on additional documentation

CA 111 Additional lamda issues -- can lamda be defined on basis of unit weight? New chapter 5 and elsewhere.

Meyer Assigned in Pittsburgh. Meyer is working on this.

CA 113 Combination of several definitions. Various locations.

CH 5 TG. CH 22 TG

All have passed Sub A. To CH 5 and CH 22 TG to c0nsider

CA 114 Various editorial items in Chapter 22 Holland 318 LB with Commentary for this chapter

ACI 318A January, 2012 CA 026

Subject: Revision of Section 22.4 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47

Code sections: 22.4 and R22.4 Basis: CA 026 originated in a previous Code cycle. It is based on recommendations from Holland that the detailed statistical requirements related to mixture proportioning that are in the Code be deleted because these topics are beyond the scope of the Code and the information is readily available in other ACI publications. Reason for Change: To remove statistical requirements related to establishing mixture proportioning from the Code because this information is not directed to the licensed design professional and it is available elsewhere in ACI publications. History: CA 026 was balloted on 318 LB 11-5 and received 27 comments of which 9 were negatives. Most of the negatives were resolved during discussions in Cincinnati. However, because several changes were made to resolve negatives, it was necessary to reballot this item at the Sub A level. CA 026 has now been reapproved by Sub A. Note that this version also contains commentary. This commentary language was either derived from existing commentary or was newly written for this version. Commentary is shown in boxed text following the applicable code section. Background: The provisions on mixture proportioning have been in the Code for many years, but the Code has evolved and it is now understood that the Code addresses the licensed design professional's responsibilities to ensure life safety. In this revision, emphasis is placed on evaluation of documentation for verifying mixture characteristics (22.4.2) and on the acceptance criteria for the concrete delivered to the project (22.5 which is 5.6 in the current code), not on how to proportion concrete mixtures. The detailed statistical requirements for establishing the basis for selecting mixture proportions are being removed from the Code because there are appropriate ACI documents that cover these details. ACI 301 provides these instructions to the contractor, and ACI 214R, which is referenced in the Commentary, is a resource for routine statistical quality control analysis and for establishing the required average strength to ensure a high likelihood of meeting the acceptance criteria. Also, many concrete producers are capable of using their quality control processes to develop appropriate mixtures without following the procedure currently called for in the Code. The Code addresses the responsibilities of the design professional and these prescriptive requirements on mixture proportioning are directed to the contractor. ACI 301 is the proper document for these instructions to the contractor. The Code needs only to provide the general performance requirements for concrete mixtures and the acceptance criteria for the delivered concrete. The requirement for the licensed design professional to review some mixtures has been in the Code for a long time. ACI 318-89 contained the following provision:

5.4.1 – If data required by 5.3 are not available, concrete proportions shall be based on water-cement ratio limits in Table 5.4, if approved by the engineer or architect.

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48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68

This provision has been modified over the years and is still present in ACI 318-11.

5.4.1 — If data required by 5.3 are not available, concrete proportions shall be based upon other experience or information, if approved by the licensed design professional.

The Code lacks a requirement on what is supposed to be done with the mixture proportioning documentation that is required to be developed. The proposed change requires that this information be submitted to the LDP for review. This review is deemed essential to ensure that the requirements, both for strength and durability, are met by the proposed concrete mixture. However, nothing in this change proposal alters the requirement that the concrete producer is ultimately responsible to provide concrete meeting the acceptance criteria of 22.5. Suggested Revisions to ACI 318-XX: NOTE: The following section 22.4 is taken from the Approved Version of Chapter 22 (dated 11-07-28) as posted on the Reorganization web site. CODE and COMMENTARY (Note that Commentary follows Code sections) 69

70 71 72

22.4 — Proportioning of concrete mixtures R22.4 – Proportioning of concrete mixtures 73

74 The 2014 edition of the Code does not include the statistical requirements for 75 proportioning concrete that were in previous editions. The Committee believes that this 76 information does not belong in the Code because it is not a responsibility of the licensed 77 design professional to proportion concrete mixtures. Further, this information is 78 available in other ACI documents, such as ACI 301 and ACI 214R. Finally, the quality 79 control procedures of some concrete producers allow meeting the acceptance criteria of

the Code without following the exact process that has been included in previous editions 80 81 of the Code. 82

83

84

22.4.1 — Selection of concrete proportions 22.4.1.1 — Proportions of materials for concrete shall be established so that the 85

86 concrete is in accordance with (a), (b), and (c): <5.2.1> Concrete mixture 87 proportions shall be established so that the concrete satisfies (a) through (c): 88 (a) Provides workability and consistency to permit concrete to be worked 89 readily into forms and around reinforcement under conditions of placement to 90 be used, without segregation or excessive bleeding;

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91 (a) Can be placed readily without segregation into forms and around 92 reinforcement under placement conditions to be used; 93 94

95

96 97

(b) Meets requirements for applicable assigned exposure classes of Chapter 5;

(c) Conforms to strength test requirements of 22.5. R22.4.1 – Selection of concrete proportions 98 99 R22.4.1.1 — This section provides requirements for developing mixture proportions. The 100

101 concrete has to have workability that is appropriate for the intended placement and 102 consolidation methods and it has to meet the durability and strength requirements of the 103 Code. The term "without segregation" is intended to provide for a cohesive mixture in 104 which aggregates remain well distributed until setting occurs. It is recognized that some 105 segregation in the form of bleeding will occur. The required workability will depend on 106 reinforcement congestion, member geometry, and the placement and consolidation 107 methods to be used. Requirements of the contractor should be considered in establishing 108 required workability of the concrete. 109 110 The Code does not include provisions for especially severe exposures, such as chemical 111 contact, high temperatures, temporary freezing and thawing conditions during the 112 construction period, abrasive conditions, alkali-aggregate reactions, or other unique 113 durability considerations pertinent to the structure. Also, the Code does not address 114 aesthetic considerations such as surface finishes. If applicable, these items should be 115 116

covered specifically in the contract documents. 22.4.1.2 -- Concrete mixture proportions shall be established in accordance with 117

118 Section 4 of ACI 301 or by an alternative method acceptable to the licensed 119 design professional. Alternative methods shall have a probability of meeting the 120 requirements of 22.5.3.2 that meets or exceeds the probability associated with 121 122

the method in ACI 301. R22.4.1.2 – Section 4 of ACI 301 contains the statistical procedures for selecting the 123

124 required average strength that were included previously in the Code. The exception 125 allows the concrete producer to provide evidence that the concrete can be proportioned 126 by an alternative method to meet the project requirements and the acceptance criteria of

22.5. The Code presumes that the probability of failure to meet the acceptance criteria in 127 128 22.5.3.2 is not more than 1 in 100. Following the method of proportioning in ACI 301 129 will maintain this level of risk. A key factor in evaluating any proposed alternative 130 proportioning method would be its ability to preserve this presumed level of risk. Refer 131 132

to ACI 214R22.8 additional information. 22.4.1.2 3 — Cementitious Concrete materials used in the Work shall correspond to those used in selecting

133 to develop concrete mixture proportions. <3.2.2> 134

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135 22.4.1.3 4 — If different materials concrete mixtures are to be used for different portions of proposed Work, each combination

136 mixture shall comply with 22.4.1.1.

<5.2.2> 137 138 139 140

R22.4.1.4—If more than one concrete mixture is used for the project, each mixture is 141

142 required to satisfy Code requirements. A change in concrete constituents, such as sources 143 or types of cementitious materials, aggregates, or admixtures, is considered a different

mixture. A minor change in mixture proportions made in response to field conditions is 144 145 146

not considered a new mixture. 22.4.1.4 — Once f′c has been determined based on strength requirements or 147

148 durability, concrete mixture proportions for the required average compressive 149 150

strength, f'cr, shall be established in accordance with 22.4.2 or 22.4.3. <5.2.3> 22.4.1.5 — Requirements Verification that the requirements for f′c are satisfied shall be based on tests

151 results of cylinders made, cured, and tested as

prescribed in 22.5.3. 152 153 154 155

<5.1.2> 22.4.2 — Establishing f'cr based on field experience Delete this entire section 156

157 22.4.2.1 — Sample standard deviation 158

159 22.4.2.1.1 — If a concrete production facility has strength test records less than 12 months old, a sample standard

160 deviation, ss, shall be established for determination of f'cr. 161

Test records from which ss is calculated shall be in accordance with (a) through (c): 162 163 164

<5.3.1.1>

165 (a) Represent materials, quality control procedures, and conditions similar to 166 those expected; and changes in materials and proportions within the test records

shall not have been more restrictive than those for proposed Work; 167 168 169 (b) Represent concrete produced to meet a specified compressive strength or

strengths within 1000 psi of f′c; 170 171

(c) Consist of at least 30 consecutive tests or two groups of consecutive tests 172 173 174

totaling at least 30 tests as defined in 22.5.1.1, except as provided in 22.4.2.1.2. 22.4.2.1.2 — If a concrete production facility does not have strength test records meeting 175 requirements of 22.4.2.1.1(c), but does have test records less than 12 months old based on 176 15 to 29 consecutive tests, ss shall be established as the product of the standard deviation 177

178 calculated from the smaller number of tests and the corresponding modification factor of Table 22.4.2.1.2. To be acceptable, test records shall meet requirements (a) and (b) of 179

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180 22.4.2.1.1, and represent only a single record of consecutive tests that span a period of at 181 182

least 45 calendar days. <5.3.1.2> <Table 5.3.1.2> Table 22.4.2.1.2 — Modification factor for sample standard deviation if fewer than 30 tests

183

are available184

185 No. of tests*

Modification factor

15 1.16 20 1.08 25 1.03 ≥30 1.00 *Interpolate for intermediate numbers of tests.

186 22.4.2.2 — Required average strength 187

188 22.4.2.2.1 — Required average compressive strength, f′cr,used as the basis for selection 189

190 of concrete proportions shall be determined from Table 22.4.2.2.1 using the sample standard deviation, ss, calculated in accordance with 22.4.2.1. <5.3.2.1> <Table 5.3.2.1> 191

192 193

Table 22.4.2.2.1 — Required average compressive strength if data are available to establish a sample standard deviat

194 ion 195

f′c, psi fcr′, psi

f′c + 1.34ss 22.4.2.2.1(a) f′c ≤ 5000 The greater of

(a) and (b): f′c + 2.33ss – 500 22.4.2.2.1(b)

f′c + 1.34ss 22.4.2.2.1(c) f′c > 5000

The greater of (c) and (d):

0.90 f′c + 2.33ss 22.4.2.2.1(d)

196 22.4.3 — Establishing f'cr without field experience Delete this entire section 197

198 199

22.4.3.1 — If a concrete production facility does not have field strength test records for 200 calculation of ss meeting requirements of 22.4.2.1, fcr′ shall be determined from Table 201

202 22.4.3.1 and documentation of average strength shall be in accordance with requirements 203 204

of 22.4.4.3. <5.3.2.2> <Table 5.3.2.2> Table 22.4.3.1 — Required average compressive strength if data are not availab

205 le to

establish a sample standard deviation206

207

f′c, psi fcr′, psi

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f′c < 3000 f′c + 1000 22.4.2.2.2(a)

3000 ≤ f′c ≤ 5000 f′c + 1200 22.4.2.2.2(b)

f′c > 5000 1.10 f′c + 700 22.4.2.2.2(c)

208 22.4.4 — Documentation of average compressive strength Delete this entire section 209

210 211

22.4.4.1 — Documentation that proposed concrete proportions will produce an average 212 compressive strength equal to or greater than required average compressive strength, fcr′, 213 shall consist of a field strength test record, several strength test records, or trial mixtures. 214

215 216

<5.3.3>

22.4.4.2 — If test records in accordance with 22.4.2.1 are used to demonstrate that 217 proposed concrete proportions will produce fcr′, such records shall comply with (a) 218

219 through (c): <5.3.3.1>

220 (a) Materials and conditions shall be similar to those expected. Changes in 221 materials, conditions, and proportions within the test records shall not have been 222 more restrictive than those for proposed Work;

223 (b) For the purpose of documenting average strength potential, test records 224 consisting of between 10 and 30 consecutive tests are acceptable, provided test 225 records encompass a period of time of at least 45 days;

226 (c) Required concrete proportions shall be permitted to be established by 227 interpolation between the strengths and proportions of two or more test records, 228 229

each of which meets the other requirements of this section. 22.4.4.3 — If an acceptable record of field test results to document f'cr is not available, 230

231 concrete proportions established from trial mixtures meeting (a) through (e) shall be 232 233

permitted: <5.3.3.2>

234 235

(a) Materials shall be those for the proposed Work.

(b) Trial mixtures shall include a range of proportions that will produce a range of 236 compressive strengths including f′cr; 237

238 239 (c) Trial mixtures shall have slumps within the range required for the proposed

Work. For air-entrained concrete, air content shall be within the tolerance 240 241 242

specified for the proposed Work;

243 (d) For each trial mixture, at least two 6 x 12 in. or three 4 x 8 in. cylinders shall be made and cured in accordance with ASTM C192. Cylinders shall be tested at 28 244 days or at test age designated for f′c; 245

246

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247 (e) The compressive strength results, at designated test age, from the trial 248 mixtures shall be used to establish the composition of the concrete mixture proposed for 249 250

the Work. 22.4.5 — Proportioning without field experience or trial mixtures Delete this entire 251 section 252

253 22.4.5.1 — If data required by 22.4.2 are not available, and if f'c is not greater than 5,000 254

255 psi, concrete proportions shall be based on other experience or information, if approved by the Licensed Design Professional. The required average compressive strength, fcr′, of 256

257 concrete produced with materials similar to those proposed for use shall be at least 1200 psi greater than f′c. <5.4.1> 258

259 22.4.6 — Reduction in required average compressive strength Delete this entire 260 section 261

262

263

22.4.6.1 — As data become available during construction, it shall be permitted to reduce 264 the amount by which the required average concrete strength f′cr must exceed f′c, provided 265

266 267

the durability requirements of 5.3 are met and (a) or (b) are satisfied. <5.5>

268 (a) Thirty or more test results are available and average of test results exceeds that required by 22.4.2.2.1, using a sample standard deviation, ss, calculated in 269

270 271

accordance with 22.4.2.1.1; (b) Fifteen to 29 test results are available and average of test results exceeds that 272 required by 22.4.2.2.1 using ss calculated in accordance with 22.4.2.1.2; 273

274 22.4.2 – Documentation of concrete mixture performance characteristics 275

276 22.4.2.1 – Documentation of concrete mixture characteristics shall be reviewed 277 by the licensed design professional before the mixture is used and before 278 making changes to mixtures already in use. Evidence of the ability of the 279 proposed mixture to comply with the requirements of 22.4.1.1 shall be included in 280 the documentation. The evidence shall be based on field test records or 281 laboratory trial batches. Field or laboratory data shall be based on materials 282 intended to be used in the proposed Work. Field test records shall represent 283 284

conditions similar to those anticipated during the proposed Work.

R22.4.2.1 – Review of the proposed concrete mixture is necessary to ensure that it is 285 286 appropriate for the project and meets all of the requirements as established by the 287 licensed design professional for strength and durability. The licensed design professional

typically reviews the documentation on a proposed concrete mixture to evaluate the 288 289 likelihood that the concrete will meet the acceptance requirements of 22.5 and includes

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290 acceptable materials. The statistical principles discussed in ACI 214R can be useful in 291

292

evaluating the likelihood that a proposed mixture will meet the requirements of 22.5.

22.4.5.1 2.2 – If field or laboratory data required by 22.4.2 are not available, and f’c is not greater than 5,000 psi, concrete proportions shall be based on other experience or information, if approved by the licensed design professional. If f’

293 294

c exceeds 5,000 psi, test data

295 documenting the characteristics of the proposed 296

297 mixtures are required. The required average compressive strength, fcr′, of 298 concrete produced with materials similar to those proposed for use shall be at 299 least 1200 psi greater than f′c. <based on 5.4.1>

Note: This provision requiring the LDP to review the concrete mixture under the 300 cited circumstances has been in the Code since at least 318-89. 301

R22.4.2.2— If f'c is not greater than 5000 psi and test data are not available, concrete 302 mixture proportions should be established to produce a sufficiently high average strength 303 such that the likelihood that the concrete would not meet the strength acceptance criteria 304 would be an acceptably low probability. Guidance on an appropriate average strength is 305 provided in ACI 214R. The purpose of this provision is to allow work to continue when 306 there is an unexpected interruption in concrete supply and there is not sufficient time for 307 testing and evaluation or for a small project where the cost of trial mixture data is not 308 justified. 309

310

311 22.4.2.3.— As data become available during construction, it shall be permitted to 312 modify a mixture that consistently exceeds the acceptance criteria of 22.5,

provided that acceptable evidence is furnished to the licensed design 313 314 professional to demonstrate that the modified mixture will comply with the 315 requirements of 22.4.1.1. <based on 5.5>

R22.4.2.3 — Often, at the beginning of a project, concrete mixtures will be proportioned 316 317 conservatively to ensure passing acceptance criteria. As test data showing actual 318 variability become available, it may be appropriate to proportion the mixture to be less 319 320

conservative. See ACI 214 R22.8 for guidance. 22.5 – Evaluation and acceptance of concrete.

Note: This section and remainder of chapter are unchanged by this proposal. 321 Section 22.5.3 is provided for reference only. 322

323 324 325 326 327

22.5.3 — Acceptance criteria for standard-cured specimens 22.5.3.1 — Specimens for acceptance tests shall be in accordance with (a) and (b):

8


(a) Sampling of concrete for strength test specimens shall be in accordance with ASTM C172; <5.6.3.1>

328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346

347

(b) Cylinders for strength tests shall be made and standard cured in accordance with ASTM C31 and tested in accordance with ASTM C39. Cylinders shall be 4 x 8 in. or 6 x 12 in. <5.6.3.2>

22.5.3.2 — Strength level of an individual class of concrete shall be acceptable if (a) and (b) are satisfied: <5.6.3.3>

(a) Every arithmetic average of any three consecutive strength tests equals or exceeds f′c;

(b) No strength test falls below f′c by more than 500 psi if f′c is 5000 psi or less; or by more than 0.10 f′c if f′c is greater than 5000 psi.

22.5.3.3 — If the requirements of 22.5.3.2 are not satisfied, steps shall be taken to increase the average of subsequent strength test results. <5.6.3.4>

9

ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012

Issued: February 11, 2012 Due Date: Monday, March 12, 2012 Revised February 13, 2012

Sorted Comments for ACI 318 Ballot LB12-2 As of March 13, 2012

NOTE: This version contains FINAL responses as approved during the 318 meeting in Dallas.

Last Name Submittal #

Line #

Vote:Y C* N** A

Comments

Becker CA026 0 N I reiterate my previous negative about any requirement that the LDP has to review a concrete mix before it can be used. I do not agree with the implication that this has been in 318 since at least 89. The reference to 5.4.1 can (and I believe should) be interpreted as the LDP allowing a different procedure. The current language does not require review of the mix design or review of the documentation for a mix design. Other than this, I would support the proposal.

Roger is concerned that on small and medium sized projects, there should not be a requirement for submitting mixture proportions. He would withdraw his negative if Sub A makes the requirement to mix submittal as an optional for the LDP to specify in Chapter 23.

Line 272.

Much discussion on recommended language. Only resolved by returning to original and finding Roger NP. Found NP, language remains same as balloted.

22.4.2.1 –Documentation of concrete mixture characteristics shall be reviewed by the licensed design professional before the mixture is used and before making changes to mixtures already in use. Documentation shall demonstrate the ability of the proposed mixture to comply with the requirements of 22.4.1.1.

Jirsa CA026 0 Y I appreciated the inclusion of the commentary material.

OK

Wyllie CA026 0 N My pervious negative vote on this issue was ruled Non Persuasive by Sub A. See my comments on page 6330. I am willing to work with Sub A, but I believe too many LDP’s do not understand concrete mixture design and since they only have ACI 318 on their desk that may be their only reference. We need to maintain enough in code and commentary to help this marginal LDP understand what a LDP needs to know. My response to Sub A’s NP is a NP back.

Found NP.


Corley CA026 54 N This gives no guidance to the LDP.

The line cited is an excerpt from the current Code that is included in the Background statement. Negative withdrawn

French CA026 77 C Change to:

“This edition of tThe 2014 does not include…”

OK, make editorial change.

Wood CA026 81 C Suggest changing “available elsewhere in ACI documents” to “available in other ACI documents.” Also suggest adding a comma after “documents.”

OK, make editorial change

French CA026 84 C Change to “included previously in previous editions of the Code.”


Wyllie CA026 84 N This commentary is a good start but let’s add a sentence that this section will attempt to give guidance to LDP on preparing specifications and review concrete mixture designs.

Find NP. Found NP

1. Code is not a textbook

2. LDP does not prepare concrete proportions

3. Specification exists – Section 4 of ACI 301

Rabbat CA026 96 N The LDP specifies an exposure class. An exposure category is not sufficient. Change:

…assigned exposure categories classes…

Correct, editorial change. Negative withdrawn based on changes.

Rabbat CA026 103 N Where are the general requirements listed?

Withdrawn based upon changes.

This section provides requirements …

French CA026 107 C Change to “remain well distributed until setting occurs.”

Otherwise it sounds like the aggregates just remain well-distributed until setting and then they segregate.

Leave as is – aggregate won’t be moving around after setting!

Parra CA026 107 C Change “The Code recognizes” to “It is recognized”


Wyllie CA026 110 N Delete this sentence that the contractor is in the best position…. I have experienced too many contractors not in that position who only want to add water so the concrete will flow better in the forms. Negative withdrawn based upon changes during 318 meeting. The required workability will depend on


reinforcement congestion, member geometry, and the placement and consolidation methods to be used. Requirements of the contractor should be considered in establishing required workability of the concrete.

French CA026 113 N This sentence needs to be reworded so that the items are parallel. When you list the examples of exposures rather than saying “chemicals” – should it be “chemical contact”

“abrasion resistance” isn’t an example of exposure, it is a quality of the concrete—should it be “abrasive conditions”?

Etc.

OK, make editorial changes. Negative withdrawn based on changes.

Cook CA026 121 N The “shall be” reference to Part 4 of ACI 310 satisfies my previous negative since that does give the same statistical requirements for the concrete as in ACI 318-11 Chapter 5.

My problem is with the blanket statement “…or by an alternative method acceptable to the licensed design professional.” The current statistical requirement is fcr = f’c +1.34s so basically the designer is insured that f’c = fcr – 1.34s. This nominal concrete strength goes hand in hand with the ACI 318 values for φ. If the licensed design professional decided to go with fcr = f’c +1.0s without changing φ then I think the overall reliability of the design decreases. I know in Appendix D we require alternative methods to use the same 5% fractile as built into the Appendix D equations and that a 5% fractile with 90% confidence is the mean – 1.64s. I am not sure what fractile fcr – 1.34s represents but any alternative method needs to be required to maintain this or reduce φ accordingly.

My negative can be resolved any one of the following:

1. Deleting “…or by an alternative method acceptable to the licensed design professional.”

2. Requiring that the LCD reduce φ factors if the alternative method does not produce the same fractile value for f’c as the ACI 301 method.

Show that the 22.5 field tests alone insure that the original ACI 318 statistical requirements for f’c have been met regardless of whatever “alternative method” is used.

Withdrawn upon change

22.4.1.2 -- Concrete mixture proportions shall be established in accordance with Section 4 of ACI 301 or by an alternative method acceptable to the licensed design professional. Alternative methods


shall have a probability of meeting the requirements of 22.5.3.2 that meets or exceeds the probability associated with the method in ACI 301.

R22.4.1.2 – Section 4 of ACI 301 contains the statistical procedures for selecting the required average strength that were included previously in the Code. The exception allows the concrete producer to provide evidence that the concrete can be proportioned by an alternative method to meet the project requirements and the acceptance criteria of 22.5. The Code presumes that the probability of failure to meet the acceptance criteria in 22.5.3.2 is not more than 1 in 100. Following the method of proportioning in ACI 301 will maintain this level of risk. A key factor in evaluating any proposed alternative proportioning method would be its ability to preserve this presumed level of risk. Refer to ACI 214R for additional information.

French CA026 121 C Should there be a year associated with ACI 310?

Actually ACI 301; year will be added in reference section. Must not be worded that ACI 301 is adopted as part of this Code.

French CA026 124 C Should there be a year associated with ACI 310?

Actually ACI 301; year will be added in reference section. Must not be worded that ACI 301 is adopted as part of this Code.

Rabbat CA026 124 C Provide on Line 129 the citation for ACI 301 to be listed in Chapter 3, Referenced Standards.

ACI 301 will be added as a reference for both Code and Commentary. In Code, must not be worded that ACI 301 is adopted as part of this Code.

Wyllie CA026 124 N Good start. Add a long paragraph for my LDP who only reads 318 about the process, experience data, test mixes, etc, in the order they should be used.

Find NP – Found NP. Code is not a textbook. ACI 301 provides specification language to be used.

Wyllie CA026 130 N The term “Work” is not code language. Sounds like a government specification. Rather than adding yet another definition, change this “Work” to “structure” and the “work” on line 134 to “project”.

Withdrawn upon discussion.

Dolan CA026 134 C As written the clause is not enforceable since it only says the mixture has to be evaluated. I suggest adding “… in accordance with 24.4.1.1” to provide an acceptance criterion.


Resolved. See Rabbat line 134

Rabbat CA026 134 N Some clarification is needed. Is each mixture evaluated or reviewed and approved by the LDP per 22.4.2.1? Withdrawn based upon changes. If different concrete mixtures are to be used for different portions of proposed Work, each combination mixture shall be evaluated comply with 24.4.1.1.

Rabbat CA026 140 N Define “minor change.”

Discuss. How about something along the lines of “A minor change in mixture proportions, such as in the ratio of fine to coarse aggregate or admixture dosages, made in response to

Withdrawn upon discussion

French CA026 274 N Can documents demonstrate?

Suggest changing to:

Evidence of the ability of the proposed mixture to comply with the requirements of 22.4.1.1 shall be included in the documentation. The evidence shall be based on field test records or laboratory trial batches.

OK, make editorial changes. Negative withdrawn based on chaanges.

French CA026 281 C Change to “Review of the proposed concrete mixture is necessary to ensure that the mixture it …”

OK, make editorial changes

Rabbat CA026 290 N When field or laboratory data are not available, is review of the mixes based on specified or required strength? R22.4.2.2 implicitly requires knowledge of the required strength that was provided in the deleted Table 22.4.3.1.

Withdrawn after discussion.

Corley CA026 292 N This is too vague. Refer to 214R in code.

Withdrawn. Cannot refer to 214R in the Code

French CA026 295 C Change to “Documenting the characteristics of the proposed mixtures…”


French CA026 303 C Reword “such that there will be a high likelihood that the concrete will meet the strength acceptance criteria…”

“high likelihood” makes it sound like there is a big chance it might not meet the criteria.

Consider turning the sentence around to say:

“such that the likelihood that the concrete would not meet the strength acceptance criteria would be an acceptably low


probability…”


Wyllie CA026 315 N This proposed Commentary sentence says same as the code. Can you be a bit more creative and helpful?

Agree. How about: “Often, at the beginning of a project, concrete mixtures will be proportioned conservatively to ensure passing acceptance criteria. As test data showing actual variability become available, it may be appropriate to proportion the mixture to be less conservative. See ACI 214 R for guidance.

Withdrawn based upon change

Wyllie CA026 346 N Too much has been deleted, I believe. We need to retain most of old 5.6, requiring concrete to be tested, the frequency, number of cylinders, what a standard-cured specimen is, etc. etc… Maybe some of this is retained before Sub A cleaned out Chapter 22 but these provisions must be retained.

Withdrawn.

These items were not deleted. They now follow the revised section on proportioning. They are included in the approved Chapter 22 that is posted on the web site.

Ballot: A01a – 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS 4/8/12] Due Date: 29 February, 2012

1 of 12

No. Name Ballot Item

Pg # Line # Y/C or N

Comment Proposed Response

1. Holland

1 Y/C

We need to add the source of the commentary sections as was done for the code sections: <x.x.x> I have identified most of the source sections and will make my comments available when this is prepared to go to 318.

Agree that Terry should do this.

2. Barth

R 5.2.1

2 33 C Since this chapter no longer includes mixing, consider: “Requirements for concrete productionmixtures are based on…”

Retain original wording. The chapter does provide requirements for the mixtures to be produced, and we are looking to remove information on how the concrete should be produced.

3. Barth

R 5.2.1

2 36 C Rest of old commentary (318-11) R 5.1 are missing and need to be in the code somewhere, could be good introduction to this chapter.

Assume this refers to the first paragraph of the old commentary R5.1 (ACI 318-11). This material would seem more appropriate for Chapter 1 and Chapter 22.

4. Carino 2 38 C Delete "and 22.5" because only 22.4 deals with proportioning. Section 22.5 is on acceptance.

Agree that “and 22.5” should be deleted.

5. Barth

R 5.2.1

2 38 N The statement as written does not appear correct as we could use anything in design not necessary linked with production of the concrete. The original text in R 5.1.1 is appears better. Consider: “It is emphasized that tThe average compressive strength of concrete as produced in accordance with 22.4 and 22.5 willshould always exceed the value of fc′ used in the structural design calculations.”

Persuasive. Revise as follows: “Concrete mixtures proportioned in accordance with 22.4 should achieve an average compressive strength that exceeds the value of fc′ used in the structural design calculations.”

6. Lobo 1 2 38 Y/C

Suggest the following revision. The strength target of the mix is as proportioned and not as produced. The concrete mixture is proportioned to achieve an average compressive strength in accordance with 22.4 and 22.5 and will always exceed the

See response to Barth comment on Line 38 (No. 5)


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value of f’c used in the structural design calculations.

7.

Holland

39 N The “required average strength” is a term that is no longer used in the code. Need to rewrite this sentence.

Not clear on this negative? The term “required average strength” is not used. Negative Withdrawn.

8. Holland

39 Y/C

Don’t understand the “will always exceed comment” that has been inserted. Was this existing language or was this something new that was inserted? Need to clarify what is intended here.

The existing language in R5.1 is “should always exceed.” See response to Barth comment on Line 38 (No. 5)

9. Lobo 1 2 39 Y/C

Suggest the following revision. The value by which the average strength of concrete exceeds f’c is based on probabilistic concepts. When concrete is designed to achieve this strength level, it ensures that the concrete strength tests will have a high probability of meeting the strength acceptance criteria in 22.5 and provide the specified design strength in the member.

Agree. Suggest the following wording: The amount by which the average strength of concrete exceeds f’c is based on probabilistic concepts. When concrete is designed to achieve this strength level, it ensures that the concrete strength tests will have a high probability of meeting the strength acceptance criteria in 22.5.

10. Carino

2 40 N

I don't agree with the statement as written. The over strength is to ensure a high likelihood of passing the acceptance criteria. The end result is that about 90 % of the concrete has to have a strength in excess of f'c. Revise as follows: "The required excess strength is based on probabilistic concepts, and is intended to ensure a high likelihood that concrete strength test results will meet the acceptance criteria in 22.5." We could also refer to ACI 214R.

Persuasive. See response to Lobo’s comment on Line 39. (No. 9)

11. Carino 2 42 N I think this sentence can also be changed to better reflect the intended meaning. We do not

Persuasive. Change to read:


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have a acceptance requirement on average concrete strength. "The durability requirements prescribed in Table 5.3.2 are to be satisfied in addition to meeting the minimum specified strength requirements of 5.2.1."

"The durability requirements prescribed in Table 5.3.2 are to be satisfied in addition to meeting the minimum specified strength requirements of 5.2.1."

12. Barth

R 5.2.1

2 46 C First sentence is unclear when it is difficult to determine the w/cm. Consider: “ Because it is difficult to accurately determine the w/cm of concrete at any time, the fc′ specified should be reasonably consistent with the w/cm required for durability.”

Agree that the wording could be improved. Revise as follows: “Because it is difficult to accurately verify determine the w/cm of concrete, …”

13. Gleich

2 46 c

Through line 47: Why is it difficult to determine the w/CM of concrete? Do we know what reasonable w/cm to strength is? If so should we tell the less knowledgeable?

No change. This could require significant additional wording. The Code is not a textbook. The existing wording makes the point.

14. Lobo 1 2 46 N Move the discussion on w/cm (46-60) to commentary associated with durability – 5.3

Persuasive. Move section and coordinate with Line 156. See response to Lobo negative on Line 156 (No. 41).

15. Meyer 46 Y/C Also on lines 49, 58 and 375, the formatting for fc' did not take.

Staff to handle.

16. Carino 2 47 C Delete "reasonably". It adds nothing. Agree. Delete “reasonably”

17. Barth

R 5.2.1

2 47 N The second sentence states that if you select an fc’ consistent with w/cm you will not exceed in the field. That may not be true when water is added in the field, hence the addition of “likely” Consider: “Selection of an fc′ that is consistent with the maximum permitted w/cm for durability will help ensure that the maximum w/cm is likely not exceeded in the field.”

See response to Carino’s negative on Line 47 (No. 18).

18. Carino 2 47 N I think we need more words to explain the intent of this sentence. The idea is to use

Persuasive. Reword as follows:


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compressive strength evaluation as a surrogate for w/cm determination. "Selection of an f'c that is consistent with the maximum permitted w/cm for durability will help ensure that the results of strength tests can be used as indications that the maximum w/cm is not exceeded in the field."

“Selection of an fc′ that is consistent with the maximum w/cm required for durability will permit results of strength tests to be used as a surrogate for w/cm, and thus help ensure that the maximum w/cm is not exceeded in the field.”

19. Barth

R 5.2.1

2 49 N Disagree with example! Designers always note the required average compressive strength for concrete and provide maximums limits w/cm. Remove example or rewrite.

Persuasive. See change made in response to Holland comment on Line 49 (No. 20).

20. Holland 49 Y/C Change “would” back to “should” as in current code.

Agree. Change “would” to “should”

21. Carino

2 50 N

I really don't understand how having test results higher than the specified strength can result in concrete exceeding the w/cm limits. I have no suggestion, because I don't know what we are trying to say. Either revise the sentence so the explanation is clear or delete it.

Persuasive. This is current Code wording, but it is not clear. Delete the sentence.

22.

Holland

50 Y/C

The sentence starting with “Because” needs help. Consider an introductory portion: “If the w/cm and f’c do not agree …” I think this is what the original is trying to say.

See response to Carino negative on Line 50 (No. 21).

23. Gleich

2 55 C Through line 60: I don’t understand why the w/cm can’t be specified for lightweight concrete other then the foot note?

New Business

24. Carino

2 55 N I think this should be moved to R5.3.2. Section 5.2.1 is addressing the selection of specified strength.

Nonpersuasive. Section 5.2.1 also references durability. And this commentary language fits with the discussion of strength and w/cm. Negative Withdrawn

25. Bondy 1 82 Y/C Suggest for consistency with the rest of the sentence, “R5.2.2 – The modulus of elasticity

No change. Section 5.2.2.1 uses “modulus of elasticity for concrete” so the existing wording


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for of concrete…” seems consistent.

26.

Holland

82 Y/C This commentary is from R8.5.2. Why was the first portion of that section omitted? It seems to provide useful information.

Assume this refers to R8.5.1. Agree the omitted sentence should be added back. It would read: “Studies leading to the expression for modulus of elasticity of concrete in 5.2.2 are summarized in Reference 5.x where Ec was defined as the slope of the line drawn from a stress of zero to a compressive stress of 0.45f’c.”

27. Lobo 1 3 82 Y/C Consider including information in first sentence of R8.5.1

Agree. See response to Holland comment on Line 82 (No. 26).

28. Carino 3 83 C Insert "elastic" before "modulus". Agree. Insert “elastic”

29.

Gleich

3 83 C

Through line 84: I have seen lower measured modulus of concrete and it has been verified since 1976 to be as low as 60 percent of calculated

No Change. New Business

30.

Hooton 1

84 N

I am surprised that measurement of E modulus by ASTM C469 is only mentioned in the Commentary R.5.2.2. Why isn’t there an option (c) in 5.2.2 that allows for direct measurement of E, rather than only allowing calculation options?

Nonpersuasive. This requires change in the current Code. Take up as New Business.

31. Carino

3 85 N We need to have more information to indicate that Eq. 5.2.2.1.a is an approximation and does not account for all the factors that affect elastic modulus. In situations where elastic modulus is a critical design parameter, tests should be conducted with the concrete materials similar those that might be used in construction to verify that the estimated elastic modulus is accurate. We should restore the reference to the work by Pauw so we don't lose track of the basis of this equation. Without such information, Eq. 5.2.2.1.a is going to take on an exactness that is not warranted.

Persuasive. See response to Holland comment on Line 82 (No. 26). Also see response to Hooton negative on Line 84 (No. 30).


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32.

Hooton 1

89 N

There is no option to measure modulus of rupture directly in this clause. So you are only allowed to estimate MOR by calculation? At least a Commentary should be added to mention ASTM C78 in a similar fashion to E modulus in 5.2.2.

Nonpersuasive. This would require a change in the current Code. Take up as New Business. (Note, it is not clear that ASTM C78 would always be appropriate for determining MOR.)

33. Lobo 1 3 89 N

Add commentary to indicate the reason for estimating fr. Suggest: The modulus of rupture is used in this Code to estimate immediate deflection (provide code reference equivalent to 9.5.2.3)

Nonpersuasive. Such language does not need to be located in this section. It does not impact the equation in 5.2.3.1. If added it should be located where fr is used.

34.

Holland 106 N There is a note in the approved version of this chapter regarding 5.2.4.2. This note should be included Until the issue is resolved. Are we considering that the issue raised in the note has been resolved by the commentary for 5.4.2?

Reinsert Note The note states: “Note: Sub A agrees with the voters for Comments 67 through 74 in 318 LB 10-1 regarding Section 5.2.4.2. A change is being processed to address these issues. Because this is a major change, we prefer to propose the changes using the normal change process showing proposed changes to the code and commentary and the supporting background information. In the interim, Subcommittee A believes that the balloted wording is acceptable and is an improvement of current provisions in 5.1.4 and 8.6.1 in ACI 318-08. Note that the balloted wording in 5.2.4.2 does not present any technical changes. It is simply an editorial revision to combine the provisions of 5.1.4 and 8.6.1.”

35. Holland 115 N There is commentary at current R5.1.5 that Persuasive. Add the following:


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should be added for 5.2.4.3. “R5.2.4.3 – Tests for splitting tensile strength of concrete (as required by 5.2.4.2) are not intended for control of, or acceptance of, the strength of concrete in the field. Indirect control will be maintained through the normal compressive strength test requirements provided by 22.5.”

36. Barth

R. 5.2.4

4 118 C Editorial, consider: A reduction factor, λ, must be used fFor the design using lightweight concrete to reflect the lower tensile strength of lightweight concrete which can reducedue to it inherrent, shear strength, friction properties, splitting resistance, bond between concrete and reinforcement, and development length requirements compared with normalweight concrete of the same compressive strength.are not taken as equivalent to normalweight concrete of the same compressive strength. A reduction factor, λ, must be used.

See response to Carino comment on Line 118 (No. 37).

37. Carino

4 118 C Delete the last sentence on line 122, and revise as follows: "The modification factor λ is used to account for the lower tensile-to-compressive strength ratio of lightweight concrete compared with normalweight concrete."

Agree. Change last sentence to read: "The modification factor λ is used to account for the lower tensile-to-compressive strength ratio of lightweight concrete compared with normalweight concrete."

38. Gleich 4 130 C Through line 135: Can the answer for l be higher than 1?

No change. Comment not clear. What is requested?

39. Carino

4 130 N In using Eq. 5.2.4.2, fct has to be the splitting tensile strength corresponding to concrete with average compressive strength equal to the specified strength. Revise as follows: "The second alternative to determine λ is based on laboratory tests of the lightweight concrete

Persuasive. Replace the sentence starting on Line 130 with the following: "The second alternative to determine λ is based on laboratory tests of the lightweight concrete having an average compressive strength


8 of 12




having an average compressive strength equal to the specified strength used in the design."

corresponding to the specified strength used in the design."

40. Bondy 1 135 Y/C Eventually we are going to have to address the incorrect use of f’c here.

Agree. A proposed change is being processed as CA111.

41. Lobo 1 6 156 N

As suggested consider including the discussion on w/cm from lines 46-60 before 156. Also suggest this wording as a lead in: Durability of concrete addressed in this Code is impacted by the permeability and diffusion of chemicals in water-saturated concrete. Reduced permeability and diffusion are primarily impacted by w/cm and the composition of cementitious materials used in concrete. Use of fly ash, slag cement and silica fume improve these characteristics of concrete at the same w/cm compared to concrete made with portland cement only. This Code places emphasis on w/cm for durability requirements. An alternative performance-based indicator of low permeability of concrete is ASTM C1202, which is more reliable in laboratory evaluations than for field-based acceptance. Alternatively, this discussion and lines 46-60 can be included prior to line 242.

Persuasive. Change as follows: Durability of concrete addressed in this Code is impacted by the resistance to fluid penetration. This is primarily affected by w/cm and the composition of cementitious materials used in concrete. Use of fly ash, slag cement and silica fume improve these characteristics of concrete at the same w/cm compared to concrete made with portland cement only. This Code places emphasis on w/cm for achieving low permeability to meet durability requirements. A performance-based indicator of resistance to fluid penetration of concrete is ASTM C1202. Also add material from Lobo negative on Line 46 (No. 14).

42. Carino

6 160 N Retain only the first sentence up to the word "temperatures". The rest of this deals with mixture proportioning, which is Chapter 22. The draft commentary in CA026 includes the other information.

Persuasive. Change first sentence (Line 160) to read: “The Code does not include provisions for especially severe exposures, such as acids or high temperatures.” Delete remainder of paragraph.

43. Holland 161 Y/C Editorial change: Change to read: See response to Carino negative on Line 160


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“…temperatures, and the Code is not concerned …”

(No. 42).

44. Barth R. 5.3

6 162 C The original wording fit better: “…..and should be covered specificallyexplicitly in the project


45. Barth

R.5.3 6 164 C I am not sure if the word “any” is necessary. See old text without it. I am OK either way. “….requirements stated in the Code and any the additional requirements of contract documents.”


46. Holland 166 Y/C Delete the title “Exposure categories and

classes.” There is no corresponding title in the code.

OK. Delete title (although it would seem a title makes the Commentary easier to follow).

47. Gleich 6 174 C Table should 5.3.1 not 4.2.1 Agree. See response to Fiorato comment on Line 174 (No. 48).

48. Fiorato

1

6 174 Y/C

Suggest deleting the phrase “as defined in Table 4.2.1” because it is not needed and it adds an internal reference that must be tracked when Code changes are made. Case in point, “Table 4.2.1” should read “Table 5.3.1.”

Agree. Delete “as defined in Table 4.2.1”

49. Holland 174 Y/C Delete “as defined in Table 4.2.1.” None of the other categories have s similar reference.

Agree. See response to Fiorato comment on Line 174 (No. 48).

50.

Hooton 1

189 Y/C

I believe that columns and walls within 3 or 4 feet of horizontal surfaces should be F2 exposure and not F1 as indicated. This is where snow and ice accumulates in northern climates, eg. around entrances where there may be a sub-level below and not soil. I think the term “in contact with soil” should be replaced with something like, “ in contact with soil or horizontal surfaces where it may be in contact with snow and ice accumulation”.

New Business?

51. Carino 7 217 C Revise as follows: Agree. Change sentence to read:


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"Examples of exposures to external sources of chlorides include concrete in direct contact with deicing chemicals, salt, salt water, brackish water, seawater, or spray from these sources."

“Examples of exposures to external sources of chlorides include concrete in direct contact with deicing chemicals, salt, salt water, brackish water, seawater, or spray from these sources.”

52.

Holland 242 Y/C Delete the title: “Requirements for concrete by exposure class.” There is no corresponding title in the code.

OK. Delete title (although it is not clear that there needs to be a corresponding title in the Code, and a title makes the Commentary easier to follow).

53. Carino 9 247 C Delete ", respectively." Agree. Delete “, respectively” 54. Carino 9 252 C Insert "specified" before "strength." Agree. Insert “specified”

55. Carino 9 265 C Revise as follows: "… and under ASTM C1157 it is Type MS."

Agree. Change to read: "… and under ASTM C1157 it is Type MS."

56. Carino

9 266 C Revise as follows: "For Exposure Class S2 (severe exposure), Type V cement with a C3A content of up to 5 percent is specified."

Agree. Change to read: "For Exposure Class S2 (severe exposure), Type V cement with a C3A content of up to 5 percent is specified."

57. Lobo 1 9 275 Y/C Consider whether line 275 to 279 needs to be addressed here or moved to R5.3.4.

No change.

58. Lobo 1 9 276 Y/C

Suggest including the following: ASTM C1012 cannot be used to evaluate the improved sulfate resistance of mixtures containing only portland cement.

The existing sentence clearly refers to “combinations of cementitious materials.” Consider addition as New Business.

59. Lobo 1 10 295 N

I prefer not to delete this. This helps evolution to performance based requirements. I agree its not in the right place. Consider my comment 6 for moving this statement under a general discussion onw/cm.

Nonpersuasive. While this may help in the evolution of performance-based requirements, it is informational and not a code requirement. What does the LDP do with this statement? Negative Withdrawn. See response to Lobo negative on Line 156 (No. 41).

60. Bondy 1 295 Y Approve the strikeout Agree 61. Fiorato 1 10 295 Y/C Agree that this sentence should be deleted. Agree


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62. Holland 295 Y/C Agree with the proposed deletion regarding C1202.

Agree

63.

Gleich

10 303 N Change the sentence to read epoxy or zinc coated bars or non-corrosive reinforcement or cover greater than

Nonpersuasive. Non-corrosive reinforcement is not defined within the context of the types of reinforcement permitted by the Code. New Business

64. Lobo 1 10 311 Y/C Suggest this section title be changed to: Chloride Limits for Exposure Category C.

Change title to “Chloride Limits for Exposure Category C”

65. Barth

R. 5.3.2

10 331 C I notice no decimals if larger than one when referring to percent. 1 percent looks awkward written as “1.00 percent” but if that is the rule I am OK.

The use of 1.00 is based on the precision of the limit required in Table 5.3.2.

66. Carino

11 336 N Delete to line 346. This leads to ambiguity. It also outdated. ACI 222.1 has been replaced by ASTM C1524, which deals only with testing aggregate.

Persuasive. Delete Lines 336 through 346.

67. Hooton 1 346 Y/C Editorial: add “the” before “same as”.


68. Bondy 1 348 Y Approve the strikeout Agree

69. Browning

348 Y/C Why delete? Because it implies an exception to a Code requirement.

70. Fiorato 1 11 348 Y/C Agree that this sentence should be deleted. Agree

71. Holland 348 Y/C Agree with the proposed deletion regarding

epoxy and zinc covered bars. If we believe this to be true, it ought to be in the code.

Agree

72. Lobo 1 11 348 Y/C

I am fine with this deletion. However, a similar statement is in line 303.

Point is well taken. However, Line 303 is not quite as egregious because it does not imply an exception to the Code. It does say it might be desirable. No change.

73. Carino 12 370 N Delete the sentence beginning with "Target Persuasive. Delete the following sentence:


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values…" It adds nothing other than to state that the table has values of target air contents.

“Target values are provided for Exposure Class F1 (moderate) and both Exposure Classes F2 and F3 (severe) exposures depending on the exposure to moisture or deicing salts.”

74. Barth R.

5.3.3.1

13 375 C Reference is made to “1.0 percent” single decimal….? (See comment page 10 line 331 above)

The use of 1.0 is based on the precision of the limit required in Section 5.3.3.1.

75. Carino 13 375 C Revise to: "…permits a 1.0 percentage point lower…"

Agree. Change to "…permits a 1.0 percentage point lower…"

76. Carino

13 389 N I suggest we explain why we have these limits. "To mitigate surface scaling, Table 5.3.3.2 establishes limitations on the amount of fly ash, other pozzolans, silica fume, and slag cement that can be included in concrete exposed to deicing chemicals (Exposure Class F3) based on research studies.4.10,4.11"

Persuasive. Change as follows: To reduce the risk of deicer scaling, …

77.

Hooton 1

390 Y/C

I would add another sentence stating that the limitations in Table 5.3.3.2 are mainly directed at flatwork, especially where hand finishing is used.

New Business?

Ballot: A02 – 2012 Approved Responses to Comments – Dallas Meeting Due Date: 7 March, 2012

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Comment Task Group Response

1. Holland

1 Y/C

We need to add the source of the commentary sections as was done for the code sections: <x.x.x> I have identified most of the source sections and will make my comments available when this is prepared to go to 318.

OK Will be included for Main ballot. Terry will add them.

2. Fiorato

1

2 43 N

Suggest revising to read: “R22.3.1.1—Type IS (≥70) is a blended cement under ASTM C595 that contains slag cement as an interground component, or slag cement as a blended component, in a quantity equal to or exceeding 70 percent by mass.”

OK, make changes as suggested.

3.

Hooton 61 Y/C R22.3.2.2 Comment: I would like to see “long history” modified as follows, “long documented history in similar exposures”. If non-spec aggregates have been used successfully, this needs to be more than a hand waving acceptance, especially regarding freeze/thaw in wet exposures, and ASR.

OK. See response to #4

4. Carino

2 62 C

The wording can be improved. The word "long" leads to unnecessary ambiguity. "Aggregates conforming to ASTM specifications are not always economically available and, in some instances, noncomplying materials may have a documented history of satisfactory performance."

OK, revise as follows: Aggregates conforming to ASTM specifications are not always economically available and, in some instances, noncomplying materials have a long history of satisfactory performance may have a documented history of satisfactory performance under similar exposure."

5. Barth 1 2 63 Y/C General: I am unclear what the The 318 editorial guidelines are being used


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steering committees directives are regarding commentary. Is the objective to edit and improve language or import commentary verbatim at this point to minimize discussion at the main committee? I am indifferent to some of the edits, however, we have managed pass on the message in the past and I wonder whether some of the changes such as the one here from “when” to “if” may justify the possible main committee discussion. Same hold true for line 65 the change from “whenever” to “if possible” and many others…

in making some these word changes.

6.

Weiss 82 Y/C Should this talk about aggregates being screened by the rebar

OK, make the following revision: (Line 83) "The size limitations on aggregates are provided to ensure proper encasement of reinforcement and to minimize honeycombing due to blockage by closely-spaced reinforcement."

7.

Weiss 89 Y/C Should this talk about silt, algae or sugars. Also should this talk about reuse

The commentary describes acceptable potable water. Some of these issues need to be addressed in C1602. Add mention of wash water as an example of nonpotable water: (line 97) "ASTM C1602 allows the use of potable water without testing and includes methods for qualifying nonpotable sources of water, such as from concrete production operations, with consideration of effects on setting time and strength."

8. Gerber R22.3.3

.1 3 90 Y/C Propose revising sentence as follows: Excessive impurities in mixing water

OK, make the following revision: "Excessive impurities in mixing water may


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may affect setting time, concrete strength, and volume stability (length change), and may also cause efflorescence or corrosion of reinforcement.

affect not only setting time, concrete strength, and volume stability (length change), butand may also cause efflorescence or corrosion of reinforcement."

9. Fiorato

1

3 92 Y/C

Suggest deleting the following sentence: “Where possible, water with high concentrations of dissolved solids should be avoided.” It is ambiguous and ASTM C1602 covers this issue quantitatively.

OK, delete the sentence. Where possible, water with high concentrations of dissolved solids should be avoided.

10. Gerber R22.3.3

.1 3 92 Y/C Is there a common understanding of what is meant by “high concentrations of dissolved solids”?

See #9

11. Carino 3 93 C Change "Where" to "If." See #9

12.

Carino

3 94 C Move this paragraph to line 101 because it results in a more logical flow of ideas.

No change. The paragraph in line 94 deals with admixtures and aggregates, not the added mixing water. See #14

13. Barth 1 3 94 Y/C Prefer original text “additive” over revised “add”

No change. The word "additive" following "admixture" can be confusing.

14. Carino

3 95 N

The current wording doesn't capture the intent and is not written clearly. We only need to convey the idea is that these additional sources of impurities need to be considering in establishing the total impurities in the concrete. We've already stated that these impurities may affect reinforcement. Revise as follows: "These additional amounts are to be considered in establishing the total impurities that may be present in the concrete."

OK, revise as suggested: "These additional amounts are to be considered in evaluating the acceptability of the total impurities that may be deleterious to concrete or steel establishing the total impurities that may be present in the concrete."


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15. Barth 1

4 126 Y/C Consider: “The presence of chloride ion may cause produce corrosion of embedded…..”

See #18

16.

Barth 1

4 126 Y/C

Code 22.3.4.3 includes limitations for prestressed concrete but the revised commentary sentence R 22.3.4.3 omitted reference prestressed concrete?

See #18

17.

Fiorato 1

4 126 Y/C

Suggest rewording as follows: “R22.3.4.3—The presence of chloride ions may produce promote corrosion of embedded aluminum…”

See #18

18.

Hooton 126 Y/C R22.3.4.3 Comment: This commentary does not say anything about the effects of chloride on corrosion of prestressing steels—the main point of the Code clause. There should be a sentence added stating that prestressing steels have a lower chloride tolerance than rebars and reference the corrosion document.

OK, add the following sentence: "Corrosion of prestressing steel is of greater concern than corrosion of nonprestressed reinforcement because of the possibility of local reduction in cross section and failure of the prestressing steel (ACI 222R)22.x. The presence of chloride ion may produce cause corrosion of embedded aluminum (e.g., conduit), especially if the aluminum is in contact with embedded steel and the concrete is in a humid environment. Protection requirements for embedded aluminum are given in 23.6." Add to the reference list: This will be the first reference that appears in the Commentary. 22.x ACI Committee 222, “Protection of Metals in Concrete Against Corrosion,” American Concrete Institute, Farmington Hills, MI, 2001, 41 pp.

19. Carino 4 128 C Change "23.X" to "23.6". OK See #18.


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20.

Fiorato 1

4 136 Y/C

Should the sentence read: “R22.3.4.4 — In some cases,The use of admixtures in concrete containing…”?

OK, make change as suggested. "In some cases, the use of admixtures in concrete containing ASTM C845 expansive cements has resulted in reduced levels of expansion or increased shrinkage values."

21.

Hooton 145 Y/C R22.3.5.1 Comment: Why is there a concern with steel fibres used with stainless steel rebars? I am told that there is no concern with plain rebars being used in combination with stainless bars (and certainly being done by our highway Dept.). So why are steel fibres thought to be different, regardless of lack of references?

Delete sentence because Code has no requirements on the use of fibers in combination with other metals. Commentary cannot be used to imply a Code requirement. Because data are not available on the potential for corrosion problems due to galvanic action, the use of deformed steel fibers in members reinforced with stainless steel bars or galvanized steel bars is not recommended.

22.

Fiorato 1

4 146 Y/C

Should the second sentence on galvanic corrosion be relocated? Perhaps R22.3.4.3 or R5.3.2 or even R6.X.X?

See #21

23.

Hooton 294 Y/C R22.5.1.1 Comment: there is only one reference cited (22.4) regarding increased variation of 4x8 cylinders relative to 6x12 cylinders, and that reference (in the title) is for 12,000 psi high strength concretes. Other references, eg. R. Day 1994, Cement, Concrete and Aggregates, Vol.16, No.1 pp21-30 conclude that there is no increase in variability for strengths ranging from 3000 to 10,000 psi concretes.

While the title of the reference implies high-strength concrete, the 20 % figure is based on review of past data presented in the source report for the SP paper. See attached excerpts after this table. We have an agenda item on this topic.

24. Gerber R22.5.1

8 300 Y/C Propose revising sentence as follows: Testing three instead of 4 by 8 in. cylinders preserves the confidence level

OK Revise as follows: "Testing three instead of two 4 by 8 in. cylinders preserves the confidence level of


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of the average strength because 4 by 8 in. cylinders tend to have approximately 20 percent higher within-test variability than 6 by 12 in. cylinders.

22.4

the average strength because 4 by 8 in. cylinders tend to have approximately 20 percent higher within-test variability than 6 by 12 in. cylinders.22.4"

25.

Carino

8 309 N

The scope of C1077 states: This practice identifies and defines the duties, responsibilities, and minimum technical requirements of testing agency personnel and the minimum technical requirements for equipment utilized in testing concrete and concrete aggregates for use in construction. The wording in the Commentary doesn't say exactly the same thing. I suggest the following revision: "ASTM C1077 identifies and defines the duties, responsibilities, and minimum technical requirements of testing agency personnel and the technical requirements for equipment used in testing concrete and concrete aggregates used in construction."

OK Make revision suggested: "ASTM C1077 identifies and defines the duties, responsibilities, and minimum technical requirements and qualifications of testing agency personnel and the technical requirements for equipment used in testing concrete and concrete aggregates used in construction."

26.

Gerber R22.5.1.2

8 315 N

If we are going to give names, the International Accreditation Service (IAS) needs to be added as a recognized agency. Or remove all agencies and refer to a “recognized accreditation body conforming to the requirements of ISO/IEC 17011” (taken from ACI 355.4)

Delete the names, and add “evaluation authority” which is term used in C1077. "Agencies that test cylinders or cores to determine compliance with Code requirements should be accredited or inspected for conformance to the requirement of ASTM C1077 by a recognized evaluation authority agency such as the American Association for Laboratory Accreditation (A2LA), AASHTO Materials Reference Laboratory (AMRL), National


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Voluntary Laboratory Accreditation Program (NVLAP), Cement and Concrete Reference Laboratory (CCRL), or their equivalent."

27.

Gerber R22.5.1.3

8 324 Y/C

Propose revising sentence as follows: Concrete testing laboratory personnel should be certified in accordance with the requirements of ACI Concrete Laboratory Testing Technician, Concrete Strength Testing Technician, the requirements of ASTM C1077, or an equivalent program.

OK Make revision "Concrete testing laboratory personnel should be certified in accordance with the requirements of ACI Concrete Laboratory Testing Technician, Concrete Strength Testing Technician, or the requirements of ASTM C1077, or an equivalent program.

28. Carino 8 326 C Add a comma after "1077." See #27

29. Holland

335 Y/C The term “required average strength” is no longer used in the Code. Rewrite to eliminate.

OK, revise as follows: "A complete record of testing allows the concrete producer to reliably establish the required average strength appropriate mixture proportions for future work.”

30. Carino 9 348 C The commentary refers specifically

to 22.5.2.1(c), so revise to "R22.5.2.1(c)"

OK, Change the section number as suggested.

31.

Carino 9 357 C This commentary is general information on the topic of sampling. It is not specific to 22.5.2.2. This should be moved to be commentary for 22.5.2.1. Change to "R22.5.2.1."

OK, Move as suggested. This will go before the Commentary in line 348.

32.

Hooton 402 Y/C R22.5.3.3 Comment: We could add another item to the list. (g) improved dispersion of cementitious materials using water reducing admixtures. This is well known, and I assume that most, but not all, suppliers use water reducers. It would be preferable to try this option rather than, for example throwing more cement at it.

OK Add as suggested. But make it (c): "(a) An increase in cementitious materials content; (b) Reduction in or better control of water content; (c) Using a water reducing admixtures to improve the dispersion of cementitious materials; (d) Other changes in mixture proportions;


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(e Reduction in delivery time; (f) Closer control of air content; (g) An improvement in the quality of the testing, including strict compliance with ASTM C172, ASTM C31, and ASTM C39."

33. Browning 420 Y/C This may need to be added to Chapter 23.

This is a note for the Chapter 23 Task Group.

34. Browning 422 Y/C 425 and 428 as well – Reverse the 4 & 6 in <5.6.4.1>

OK

35. Fiorato 1 10 422 Y/C Replace <5.4.6.1> with <5.6.4.1> OK 36. Fiorato 1 11 425 Y/C Replace <5.4.6.3> with <5.6.4.3> OK 37. Fiorato 1 11 428 Y/C Replace <5.4.6.2> with <5.6.4.2> OK

38.

Hooton 430 Y/C R22.5.4.1 Comment: One of the big issues with using field cured cylinders is that large structural elements that will generate temperature rise during curing. Test cylinders will not mimic the strength gain of such elements. A warning statement related to this needs to be added.

OK Add a new paragraph as follows: The Code provides a specific criterion in 22.5.4.2 for judging the adequacy of field curing. For a reasonably valid comparison to be made, field-cured cylinders and companion laboratorystandard-cured cylinders are made from the same sample. Field-cured cylinders are cured under the same conditions as the structure. If the structure is protected from the elements, the cylinders should be protected. Cylinders related to members not directly exposed to weather should be cured adjacent to those members and provided with the same degree of protection and method of curing. The field cylinders should not be treated more favorably than the elements they represent. In evaluating test results of field-cured cylinders, it should be recognized that even if cylinders are protected as the structure they may not experience the same temperature


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history as the concrete in the structure. This is because heat of hydration may be dissipated differently in a cylinder compared with the structural element.

39.

Weiss 430 Y/C I have been confused about what is meant by lab cured.

See #38 and #41 We need to change all occurrences of "laboratory-cured" to "standard-cured" in the following provisions of the approved version of Chapter 22: 22.5.4.1.(a), 22.5.4.2, 22.5.6.1

40.

Fiorato 1 11 434 Y/C Should the two instances of the word “are” be replaced with “should be” in this line (two different sentences).

The word "are" is used because the Commentary cannot relieve Code requirements. "Should" implies an option is acceptable.

41. Carino

11 445 C Some changes are suggested to tighten up the language: "R22.5.4.2—Positive guidance is provided in the Code concerning the interpretation of tests of field-cured cylinders. Research has shown that the strength of cylinders protected and cured to simulate good field practice should be at least about 85 percent of the strength of standard-cured cylinders, if both are tested at the age designated for f'c. This percentage has been set as a rational basis for judging the adequacy of field curing. The comparison is made between the measured strengths of companion field-cured and laboratory-cured cylinders, not between the strength of field-cured cylinders and the specified value of f'c. However, test results for field-

OK Make suggested changes: Positive guidance is provided in the Code concerning the interpretation of tests of field-cured cylinders. Research has shown that the strength of cylinders protected and cured to simulate good field practice should be at least about 85 percent of standard-cured cylinders, if both are tested at the age designated for f'c. This percentage has been set as a rational basis for judging the adequacy of field curing. The comparison is made between the measured strengths of companion field-cured and standard laboratory-cured cylinders, not between the strength of field-cured cylinders and the specified value of f'c. However, test results for the field-cured cylinders are considered satisfactory if the strength of field-cured cylinders exceed the f'c by more than 500 psi, even though they fail to reach 85 percent of the strength of companion laboratory


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cured cylinders are considered satisfactory if the strength of field-cured cylinders exceed f'c by more than 500 psi, even though they fail to reach 85 percent of the strength of companion laboratory-cured cylinders. The 85 percent criterion is based on the assumption that concrete is maintained above 50 °F and in a moist condition for at least the first 7 days after placement, or high-early-strength concrete is maintained above 50 °F and in a moist condition for at least the first 3 days after placement."

standard-cured cylinders. The 85 % percent criterion is based on the assumption that concrete is maintained above 50 °F and in a moist condition for at least the first 7 days after placement, or high-early-strength concrete is maintained above 50 °F and in a moist condition for at least the first 3 days after placement.

42.

Browning 453 Y/C Is this new commentary? I did not find it in 318-11.

This is new Commentary based on the current "R5.11.4 — In addition to requiring a minimum curing temperature and time for normal- and high-early-strength concrete, the Code provides a specific criterion in 5.6.4 for judging the adequacy of field curing."

43.

Fiorato 1 11 457 N Not sure what to recommend here. The sentence “If the tests indicate a possible serious deficiency in strength of concrete in the structure, core tests may be required, with or without supplemental wet curing, to check the structural adequacy, as provided in 22.5.6.” is confusing. Does it imply acceptance of concrete based on field curing? What supplemental wet curing are we talking about? Is this sentence in the

Tony is right. This commentary should be paired with 22.5.6.1. The provisions on field-cured cylinders are intended to apply to the Contractor responsible for protection and curing and is an acceptance of the concrete in the structure as opposed to acceptance of the concrete delivered to the project. The use of these tests is at the option of the LDP or building official. 22.5.6.1 — If any strength test of laboratory-cured cylinders falls below f′c by more than the values given in 22.5.3.2(b) or if tests of


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correct location? Should it be somewhere in 22.5.6?

field-cured cylinders in accordance with 22.5.4 indicate deficiencies in protection and curing, steps shall be taken to ensure that structural capacity of the structure is not jeopardized. <5.6.5.1> Move the two sentences to Commentary to R22.5.6.1 "If the strength of field-cured cylinders do not conform to 22.5.4.2 provide satisfactory strength by this comparison, steps need to be taken to improve the curing. If the supplemental in-place tests (see R22.5.6) confirm a possible serious deficiency in strength of concrete in the structure, core tests may be required, with or without supplemental wet curing, to check the structural adequacy, as provided in 22.5.6.

44. Barth 1

11 457 Y/C What is “possible serious deficiency”? Revised and provide clear guidance.

See #43

45.

Browning 461 Y/C It would flow/read better if 22.5.5 came after 22.5.6

Comment withdrawn Note: Remove hyphen from title 22.5.6 Investigation of low strength test results (no hyphen needed)

46. Carino

12 504 C The word "safe" is not needed. Revise as follows: "For cores, if required, conservative acceptance criteria are provided in 22.5.6.4 that should ensure structural adequacy for virtually any type of construction.22.9-22.12"

OK Make suggested changes: "For cores, if required, conservatively safe acceptance criteria are provided in 22.5.6.4 that should ensure structural adequacy for virtually any type of construction.22.9-22.12"

47. Holland

504 Y/C I would make the discussion of cores a new paragraph.

OK Make suggested changes: "…the same structure rather than as quantitative estimates of strength.


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For cores, if required, conservatively…"

48.

Carino 12 508 C Improve the wording as follows: "If the strength of cores obtained in accordance with 22.5.6.3 fail to comply with 22.5.6.4, it may be practical, particularly in the case of floor or roof systems, for the building official to require a load test (Chapter 24)."

OK Make suggested changes: "If the strength of cores core tests performed obtained in accordance with 22.5.6.3 fail to comply with 22.5.6.4, it may be practical, particularly in the case of floor or roof systems, for the building official to require a load test (Chapter 24)."

49.

Carino 13 543 C The word "common" has multiple meanings and its use in this sentence is ambiguous. Change "common" to "standard".

OK Make suggested changes: Thus, to provide reproducible moisture conditions that are representative of in-place conditions, a common standard moisture conditioning procedure that permits dissipation of moisture gradients is prescribed for cores.

50. Browning 547 Y/C At the end of 22.5.6.4 add <5.6.5.4> OK

51.

Carino 13 554 N Improve the wording: "An average core strength of at least 85 percent of the specified strength is realistic.22.10 It is not realistic, however, to expect the average core strength to be equal to f'c , because of differences in the size of specimens, conditions of obtaining specimens, degree of consolidation, and curing conditions.

OK Make the suggested changes: Core tests having aAn average core strength of at least 85 percent of the specified strength are is realistic.22.10 To expect core tests to be equal to f'c is not realistic, It is not realistic, however, to expect the average core strength to be equal to f'c, because of differences in the size of specimens, conditions of obtaining specimens, samples, and procedures for degree of consolidation, and curing conditions., do not permit equal values to be obtained.

52. Bondy 1 13 556 Y/C I realize this wording is the same as 318-11, but “…do not permit equal values to be obtained” is pretty all-encompassing. Do we really want to say that? How

See #51


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about softening it a bit, “…and procedures for curing, do not permit equal values to be obtained generally do not result in equal values being obtained.”

53. Lobo

1

13 556 Y/C

Suggest adding this statement to cores because of concern out there that age of cores is later than age for f’c and therefore should be at a higher level than permitted: These criteria for core strengths are established with consideration that cores will typically be extracted at an age later than that specified for f’c.

OK Add the following: "The acceptance criteria for core strengths have been established with consideration that cores for investigating low strength test results will typically be extracted at an age later than specified for f'c. The Code does not intend that core strengths be adjusted for the age of the cores."

54.

Fiorato 1 14 571 N Suggest rewording as follows: “Past success experience with grout for bonded tendons has indicated that portland cement can be successfully used. A blanket endorsement of all cementitious materials for use with this grout is inappropriate because of There is a lack of experience or tests with cementitious materials other than portland cement and a concern that some cementitious materials might introduce chemicals that are harmful to tendons. Therefore such systems are not currently permitted in the Code. Use of finely graded sand in the grout should only be considered with large ducts having large void areas. Guidance can be found in xxx.”

OK See also #57. Make the following changes: "Past success Experience with grout for bonded tendons has been with indicates that portland cement can be used successfully. A blanket endorsement of all cementitious materials for use with this grout is inappropriate because of There is a lack of experience or tests with cementitious materials other than portland cement and a concern that some cementitious materials might introduce chemicals that are harmful to tendons. Therefore, such systems are not permitted in the Code. Use of finely graded sand in the grout should only be considered with large ducts having large void areas. Neat cement grout is used in almost all building construction.


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Guidance on materials for grout and grout properties can be found in ACI 423.8R22.y and the PTI grouting specification.22.x" Add these references: 22.y 423.8R, 2010, Report on Corrosion and Repair of Grouted Multistrand and Bar Tendon Systems 22.x PTI Committee on Grouting Specifications, 2003, “Specification for Grouting of Post-Tensioned Structures,” second edition, Post-Tensioning Institute, Farmington Hills, MI, 60 pp.

55.

Hooton 571 Y/C R22.6.1 Comment: I am surprised that only Portland cement is still recommended for grouting. Our highway dept. has used silica fume modified PT grouts for at least 20 years to improve resistance to corrosion and I know that fly ash is used in other areas for PT grouts.

We are waiting on Sub G to update 22.6.

56.

Fiorato 1 14 591 Y/C Is the statement “Aluminum powder or other expansive admixtures, if approved, should produce an unconfined expansion of 5 to 10 percent.” a Code provision in disguise? New Business?

Delete sentence. Code has no provision related to expansive components. See #54. "Substances known to be harmful to tendons, grout, or concrete are chlorides, fluorides, sulfites, and nitrates. Aluminum powder or other expansive admixtures, if approved, should produce an unconfined expansion of 5 to 10 percent. Neat cement grout is used in almost all building construction."

57.

Fiorato 1 14 592 N Suggest deleting “Neat cement grout is used in almost all building construction.” How does it help the LDP? Part of the problem may be the

OK Move sentence to R22.6.1. See #54.


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fact that this sentence is no longer “connected” to the sentence on use of finely graded sand (see Comment 11).

58.

Fiorato 1 15 599 N Suggest rewording to read: “The handling and placing properties of grout are usually given more consideration of more concern than strength when designing grout mixtures.

OK Revise as follows: "The handling and placing properties of grout are usually given more consideration of more concern than strength when proportioning designing grout mixtures."


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Background report for statement in Ref. 22.4