Standard Specification for Chemical Admixtures for Concrete

SCOPE
1.1 This specification covers materials for use as chemical admixtures to be added to hydraulic-cement concrete mixtures in the field for the purpose or purposes indicated for the seven types as follows:
1.1.1 Type A—Water-reducing admixtures,
1.1.2 Type B—Retarding admixtures,
1.1.3 Type C—Accelerating admixtures,
1.1.4 Type D—Water-reducing and retarding admixtures,
1.1.5 Type E—Water-reducing and accelerating admixtures,
1.1.6 Type F—Water-reducing, high range admixtures, and
1.1.7 Type G—Water-reducing, high range, and retarding admixtures.
1.2 This specification stipulates tests of an admixture with suitable concreting materials as described in 11.1-11.3 or with cement, pozzolan, aggregates, and an air-entraining admixture proposed for specific work (11.4). Unless specified otherwise by the purchaser, the tests shall be made using concreting materials as described in 11.1-11.3.
Note 1—It is recommended that, whenever practicable, tests be made using the cement, pozzolan, aggregates, air-entraining admixture, and the mixture proportions, batching sequence, and other physical conditions proposed for the specific work () because the specific effects produced by chemical admixtures may vary with the properties and proportions of the other ingredients of the concrete. For instance, Types F and G admixtures may exhibit much higher water reduction in concrete mixtures having higher cement factors than that listed in .
Mixtures having a high range water reduction generally display a higher rate of slump loss. When high-range admixtures are used to impart increased workability (6 to 8-in. slump [150 to 200-mm]), the effect may be of limited duration, reverting to the original slump in 30 to 60 min depending on factors normally affecting rate of slump loss. The use of chemical admixtures to produce high-slump (flowing) concrete is covered by Specification C 1017.
Note 2—The purchaser should ensure that the admixture supplied for use in the work is equivalent in composition to the admixture subjected to test under this specification (see Section 6, Uniformity and Equivalence).
Note 3—Admixtures that contain relatively large amounts of chloride may accelerate corrosion of prestressing steel. Compliance with the requirements of this specification does not constitute assurance of acceptability of the admixture for use in prestressed concrete.
1.3 This specification provides for three levels of testing.
1.3.1 Level 1—During the initial approval stage, proof of compliance with the performance requirements defined in demonstrates that the admixture meets the requirements of this specification. Uniformity and equivalence tests of Section shall be carried out to provide results against which later comparisons can be made.
1.3.2 Level 2—Limited retesting is described in 5.2, 5.2.1 and 5.2.2. Proof of compliance with the requirements of demonstrates continued conformity of the admixture with the requirements of the specification.
1.3.3 Level 3—For acceptance of a lot or for measuring uniformity within or between lots, when specified by the purchaser, the uniformity and equivalence tests of Section 6 shall be used.
1.4 The values stated in either inch-pound or SI units shall be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining values in any way.
1.5 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.
1.6 The following precautionary caveat pertains only to the test method sections, Sections 11-18 of this Specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practi...

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ASTM C494/C494M-04 - Standard Specification for Chemical Admixtures for Concrete
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C 494/C 494M – 04
Standard Specification for
1
Chemical Admixtures for Concrete
ThisstandardisissuedunderthefixeddesignationC494/C494M;thenumberimmediatelyfollowingthedesignationindicatestheyear
of original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.
A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
NOTE 2—The purchaser should ensure that the admixture supplied for
1. Scope
use in the work is equivalent in composition to the admixture subjected to
1.1 This specification covers materials for use as chemical
test under this specification (see Section 6, Uniformity and Equivalence).
admixtures to be added to hydraulic-cement concrete mixtures
NOTE 3—Admixtures that contain relatively large amounts of chloride
in the field for the purpose or purposes indicated for the seven
may accelerate corrosion of prestressing steel. Compliance with the
types as follows: requirements of this specification does not constitute assurance of accept-
ability of the admixture for use in prestressed concrete.
1.1.1 Type A—Water-reducing admixtures,
1.1.2 Type B—Retarding admixtures,
1.3 This specification provides for three levels of testing.
1.1.3 Type C—Accelerating admixtures,
1.3.1 Level 1—During the initial approval stage, proof of
1.1.4 Type D—Water-reducing and retarding admixtures,
compliance with the performance requirements defined in
1.1.5 Type E—Water-reducing and accelerating admixtures,
Table 1 demonstrates that the admixture meets the require-
1.1.6 Type F—Water-reducing, high range admixtures, and
mentsofthisspecification.Uniformityandequivalencetestsof
1.1.7 Type G—Water-reducing, high range, and retarding
Section 6 shall be carried out to provide results against which
admixtures.
later comparisons can be made.
1.2 This specification stipulates tests of an admixture with
1.3.2 Level 2—Limited retesting is described in 5.2, 5.2.1
suitable concreting materials as described in 11.1-11.3 or with
and 5.2.2. Proof of compliance with the requirements of Table
cement, pozzolan, aggregates, and an air-entraining admixture
1demonstratescontinuedconformityoftheadmixturewiththe
proposed for specific work (11.4). Unless specified otherwise
requirements of the specification.
by the purchaser, the tests shall be made using concreting
1.3.3 Level 3—For acceptance of a lot or for measuring
materials as described in 11.1-11.3.
uniformity within or between lots, when specified by the
purchaser, the uniformity and equivalence tests of Section 6
NOTE 1—It is recommended that, whenever practicable, tests be made
shall be used.
using the cement, pozzolan, aggregates, air-entraining admixture, and the
mixture proportions, batching sequence, and other physical conditions 1.4 The values stated in either inch-pound or SI units shall
proposedforthespecificwork(11.4)becausethespecificeffectsproduced
be regarded separately as standard. The values stated in each
by chemical admixtures may vary with the properties and proportions of
system may not be exact equivalents; therefore, each system
the other ingredients of the concrete. For instance, Types F and G
must be used independently of the other, without combining
admixturesmayexhibitmuchhigherwaterreductioninconcretemixtures
values in any way.
having higher cement factors than that listed in 12.1.1.
1.5 The text of this standard references notes and footnotes
Mixtureshavingahighrangewaterreductiongenerallydisplayahigher
which provide explanatory material.These notes and footnotes
rate of slump loss. When high-range admixtures are used to impart
increased workability (6 to 8-in. slump [150 to 200–mm]), the effect may (excluding those in tables and figures) shall not be considered
be of limited duration, reverting to the original slump in 30 to 60 min
as requirements of the standard.
depending on factors normally affecting rate of slump loss. The use of
1.6 The following precautionary caveat pertains only to the
chemical admixtures to produce high-slump (flowing) concrete is covered
test method sections, Sections 11-18 of this Specification: This
by Specification C1017.
standard does not purport to address all of the safety concerns,
if any, associated with its use. It is the responsibility of the user
1
of this standard to establish appropriate safety and health
This specification is under the jurisdiction of ASTM Committee C09 on
Concrete Aggregates and is the direct responsibility of Subcommittee C9.23 on
practices and determine the applicability of regulatory limita-
Chemical Admixtures.
tions prior to use.
Current edition approved Jan. 1, 2004. Published February 2004. Originally
e1
approved in 1962. Last previous edition approved in
...

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