-
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 todays 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 All negatives were either withdrawn or found non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.
1
-
ACI 318A January, 2012 CA 026
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): 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;
2
-
ACI 318A January, 2012 CA 026
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. 134
3
-
ACI 318A January, 2012 CA 026
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.
137 138 139 140
R22.4.1.4If 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 fc 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. 22.4.1.5 Requirements Verification that the requirements
for fc 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
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
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 fc; 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
4
-
ACI 318A January, 2012 CA 026
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. 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, fcr,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. 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
fc, psi fcr, psi
fc + 1.34ss 22.4.2.2.1(a) fc 5000
The greater of (a) and (b): fc + 2.33ss 500 22.4.2.2.1(b)
fc + 1.34ss 22.4.2.2.1(c) fc > 5000
The greater of (c) and (d):
0.90 fc + 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. Table 22.4.3.1 Required average compressive
strength if data are not availab
205 le to
establish a sample standard deviation206
207
fc, psi fcr, psi
5
-
ACI 318A January, 2012 CA 026
fc < 3000 fc + 1000 22.4.2.2.2(a)
3000 fc 5000 fc + 1200 22.4.2.2.2(b)
fc > 5000 1.10 fc + 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
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):
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:
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 fcr;
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 fc; 245
246
6
-
ACI 318A January, 2012 CA 026
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 fc. 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 fcr must exceed fc, provided 265
266 267
the durability requirements of 5.3 are met and (a) or (b) are
satisfied.
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
7
-
ACI 318A January, 2012 CA 026
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 fc 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
fc.
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.
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
-
ACI 318A January, 2012 CA 026
(a) Sampling of concrete for strength test specimens shall be in
accordance with ASTM C172;
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.
22.5.3.2 Strength level of an individual class of concrete shall
be acceptable if (a) and (b) are satisfied:
(a) Every arithmetic average of any three consecutive strength
tests equals or exceeds fc;
(b) No strength test falls below fc by more than 500 psi if fc
is 5000 psi or less; or by more than 0.10 fc if fc 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.
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 LDPs 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 As NP is a NP
back.
Found NP.
-
ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012
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.
OK, make editorial change
Wyllie CA026 84 N This commentary is a good start but lets 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 wont be moving around after setting!
Parra CA026 107 C Change The Code recognizes to It is
recognized
OK, make editorial change
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
-
ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012
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 isnt an example of exposure, it is a quality
of the concreteshould 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 = fc +1.34s so basically the
designer is insured that fc = fcr 1.34s. This nominal concrete
strength goes hand in hand with the ACI 318 values for . If the
licensed design professional decided to go with fcr = fc +1.0s
without changing 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 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 factors if the alternative
method does not produce the same fractile value for fc as the ACI
301 method.
Show that the 22.5 field tests alone insure that the original
ACI 318 statistical requirements for fc 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
-
ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012
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.
-
ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012
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
OK, make editorial changes
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
-
ACI 318-14 Ballot LB12-2 Sorted Comments March 13, 2012
probability
OK, make editorial changes
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: 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)
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
2 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
value of fc 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
Dont 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 fc 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 fc 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 Lobos 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:
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
3 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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 Carinos 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:
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
4 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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 fc 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 dont understand why the w/cm cant 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
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
5 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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 0.45fc.
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 isnt 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).
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
6 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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:
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
7 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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, , 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, , 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 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 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 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 is based on
laboratory tests of the lightweight concrete having an average
compressive strength
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
8 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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 fc 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
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
9 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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
See response to Carino negative on Line 160 (No. 42).
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.
See response to Carino negative on Line 160 (No. 42).
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:
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
10 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
"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
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
11 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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. See
response to Carino negative on Line 336 (No. 66).
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:
-
Ballot: A01a 2012 [DRAFT RESPONSES TO NEGATIVES AND COMMENTS
4/8/12] Due Date: 29 February, 2012
12 of 12
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Proposed Response
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
1 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
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: 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: R22.3.1.1Type 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
-
Ballot: A02 2012 Approved Responses to Comments Dallas Meeting
Due Date: 7 March, 2012
2 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Task Group Response
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
-
Ballot: A02 2012 Approved Responses to Comments Dallas Meeting
Due Date: 7 March, 2012
3 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Task Group Response
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."
-
Ballot: A02 2012 Approved Responses to Comments Dallas Meeting
Due Date: 7 March, 2012
4 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Task Group Response
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: R22.3.4.3The 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
steelsthe 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.
-
Ballot: A02 2012 Approved Responses to Comments Dallas Meeting
Due Date: 7 March, 2012
5 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Task Group Response
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
-
Ballot: A02 2012 Approved Responses to Comments Dallas Meeting
Due Date: 7 March, 2012
6 of 16
No. Name Ballot Item
Pg # Line # Y/C or N
Comment Task Group Response
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