Designation: C 494/C 494M – 99ae1
Standard Speciﬁcation for
Chemical Admixtures pertaining to Concrete1
This kind of standard can be issued underneath the ﬁxed naming C 494/C 494M; the phone number immediately following the designation shows the year of original re-homing or, regarding revision, 12 months of last revision. A number in parentheses indicates the season of last reapproval. A superscript epsilon (e) indicates an editorial change because the last version or reapproval. This common has been approved for use by simply agencies of the Department of Defense.
e1 NOTE—Range benefit in 12. 2 . 2 was editorially corrected This summer 2001.
1 . Scope 1 ) 1 This kind of speciﬁcation addresses materials to be used as chemical admixtures being added to hydraulic-cement concrete blends 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 . two Type B—Retarding admixtures, 1 ) 1 . three or more Type C—Accelerating admixtures, 1 ) 1 . 5 Type D—Water-reducing and retarding admixtures, 1 ) 1 . your five Type E—Water-reducing and speeding up admixtures, 1 ) 1 . six Type F—Water-reducing, high range admixtures, and 1 . 1 . 7 Type G—Water-reducing, large range, and retarding admixtures. 1 . a couple of This speciﬁcation stipulates assessments of an commixture with suitable concreting components as referred to in 14. 1-11. three or more or with cement, pozzolan, aggregates, and an air-entraining admixture proposed for speciﬁc work (11. 4). Except if speciﬁed otherwise by the purchaser, the assessments shall be built using concreting materials while described in 11. 1-11. 3. NOTICE 1—It is recommended that, anytime practicable, checks be made making use of the cement, pozzolan, aggregates, air-entraining admixture, plus the mixture amounts, batching collection, and other physical conditions recommended for the speciﬁc job (11. 4) because the speciﬁc effects manufactured by chemical admixtures may vary with all the properties and proportions of some other ingredients from the concrete. For instance, Types Farreneheit and G admixtures may well exhibit greater water reduction in concrete mixes having higher cement elements than that listed in 12. 1 . 1 ) Mixtures using a high selection water decrease generally screen a higher rate of slump reduction. When high-range admixtures are used to impart improved workability (6 to 8-in. slump [150 to 200–mm]), the effect can be of limited duration, reverting to the original slump in 30 to 60 minutes depending on factors normally impacting on rate of slump damage. The use of substance admixtures to create 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 make up to the fortification subjected to test under this kind of speciﬁcation (see Section six, Uniformity and Equivalence). NOTE 3—Admixtures that may contain relatively considerable amounts of chloride may increase the speed of corrosion of prestressing metallic. Compliance with the 1 This kind of speciﬁcation is usually under the legislation of ASTM Committee C09 on Cement Aggregates which is the immediate responsibility of Subcommittee C9. 23 in Chemical Admixtures. Current edition approved April. 10, 99. Published Dec 1999. Formerly published as C 494 – 62. Last prior edition C 494 – 99.
requirements of this speciﬁcation does not amount to assurance of acceptibility with the admixture use with prestressed concrete.
1 . three or more This speciﬁcation provides for 3 levels of assessment. 1 . a few. 1 Level 1—During your initial approval stage, proof of complying with the efficiency requirements deﬁned in Desk 1 demonstrates that the fortification meets the requirements of this speciﬁcation. Uniformity and equivalence testing of Section 6 shall be carried out to provide results against which later on comparisons could be made. 1 . 3. 2 Level 2—Limited retesting is definitely described in 5. two, 5. installment payments on your 1 and 5. installment payments on your 2 . Proof of compliance with all the requirements of Table one particular demonstrates continued conformity with the admixture together with the requirements with the speciﬁcation. 1 ) 3. three or more Level 3—For acceptance of the lot or for testing uniformity within just...
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