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 (11.4) 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 12.1.
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 Table 1 demonstrates that the admixture meets the requirements of this specification. Uniformity and equivalence tests of Section 6 shall be carried out to provide results against which later comparisons can be made.
1.3.2 Level 2--Limited retesting is described in , and . 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 sa...

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09-Oct-1999
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ASTM C494/C494M-99ae1 - 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
e1
Designation: C 494/C 494M – 99a
Standard Specification for
1
Chemical Admixtures for Concrete
This standard is issued under the fixed designation C 494/C 494M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number 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.
1
e NOTE—Range value in 12.2.2 was editorially corrected July 2001.
NOTE 3—Admixtures that contain relatively large amounts of chloride
1. Scope
may accelerate corrosion of prestressing steel. Compliance with the
1.1 This specification covers materials for use as chemical
requirements of this specification does not constitute assurance of accep-
admixtures to be added to hydraulic-cement concrete mixtures
tibility of the admixture for use in prestressed concrete.
in the field for the purpose or purposes indicated for the seven
1.3 This specification provides for three levels of testing.
types as follows:
1.3.1 Level 1—During the initial approval stage, proof of
1.1.1 Type A—Water-reducing admixtures,
compliance with the performance requirements defined in
1.1.2 Type B—Retarding admixtures,
Table 1 demonstrates that the admixture meets the require-
1.1.3 Type C—Accelerating admixtures,
ments of this specification. Uniformity and equivalence tests of
1.1.4 Type D—Water-reducing and retarding admixtures,
Section 6 shall be carried out to provide results against which
1.1.5 Type E—Water-reducing and accelerating admixtures,
later comparisons can be made.
1.1.6 Type F—Water-reducing, high range admixtures, and
1.3.2 Level 2—Limited retesting is described in 5.2, 5.2.1
1.1.7 Type G—Water-reducing, high range, and retarding
and 5.2.2. Proof of compliance with the requirements of Table
admixtures.
1 demonstrates continued conformity of the admixture with the
1.2 This specification stipulates tests of an admixture with
requirements of the specification.
suitable concreting materials as described in 11.1-11.3 or with
1.3.3 Level 3—For acceptance of a lot or for measuring
cement, pozzolan, aggregates, and an air-entraining admixture
uniformity within or between lots, when specified by the
proposed for specific work (11.4). Unless specified otherwise
purchaser, the uniformity and equivalence tests of Section 6
by the purchaser, the tests shall be made using concreting
shall be used.
materials as described in 11.1-11.3.
1.4 The values stated in either inch-pound or SI units shall
NOTE 1—It is recommended that, whenever practicable, tests be made
be regarded separately as standard. The values stated in each
using the cement, pozzolan, aggregates, air-entraining admixture, and the
system may not be exact equivalents; therefore, each system
mixture proportions, batching sequence, and other physical conditions
must be used independently of the other, without combining
proposed for the specific work (11.4) because the specific effects produced
values in any way.
by chemical admixtures may vary with the properties and proportions of
1.5 The text of this standard references notes and footnotes
the other ingredients of the concrete. For instance, Types F and G
which provide explanatory material. These notes and footnotes
admixtures may exhibit much higher water reduction in concrete mixtures
having higher cement factors than that listed in 12.1.1. (excluding those in tables and figures) shall not be considered
Mixtures having a high range water reduction generally display a higher
as requirements of the standard.
rate of slump loss. When high-range admixtures are used to impart
1.6 The following precautionary caveat pertains only to the
increased workability (6 to 8-in. slump [150 to 200–mm]), the effect may
test method sections, Sections 11-18 of this Specification: This
be of limited duration, reverting to the original slump in 30 to 60 min
standard does not purport to address all of the safety concerns,
depending on factors normally affecting rate of slump loss. The use of
if any, associated with its use. It is the responsibility of the user
chemical admixtures to produce high-slump (flowing) concrete is covered
by Specification C 1017. of this standard to establish appropriate safety and health
NOTE 2—The purchaser should ensure that the admixture supplied for
practices and determine the applicability of regulatory limita-
use in the work is equivalent in composition to the admixture subjected to
tions prior to use.
test under this specification (see Section 6, Uniformity and Equivalence).
2. Referenced Documents
2.1 ASTM Standards:
1
This specification is under the jurisdiction of ASTM Committee C09 on
2
C 33 Specification for Concrete Aggregates
...

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