This specification covers chemical admixtures to be added to hydraulic cement concrete mixtures for use in producing flowing concrete. The two types of chemical admixtures are: Type I—plasticizing; and Type II—plasticizing and retarding. Tests of the chemical admixtures with reference concreting materials or with concrete-making materials proposed for specific work are specified. Three levels of testing are discussed: Level 1, Level 2, and Level 3. Type of admixtures shall conform to the physical requirements: time of setting, increase in slump, compressive strength, flexural strength, length of change after days of drying, and relative durability factor. Uniformity and equivalence shall be established by the following requirements: infrared analysis, residue by oven drying (liquid and nonliquid admixtures), and specific gravity (liquid admixtures). Tests for quality, uniformity, and equivalence shall be made. Samples of freshly mixed concrete shall be tested according to slump, air content, time of setting, and water content and unit weight. Hardened concrete shall be tested according to the following: compressive strength, flexural strength, resistance to freezing and thawing, and length change.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

1.1 This specification covers two types of chemical admixtures to be added to hydraulic cement concrete mixtures for the purpose of producing flowing concrete. The types are as follows:

1.1.1 Type I - Plasticizing, and

1.1.2 Type II - Plasticizing and retarding.

1.2 This specification stipulates tests of a chemical admixture with reference concreting materials or with concrete-making materials proposed for specific work. Unless otherwise specified by the purchaser, the tests shall be made using reference concreting materials.

1.3 If a chemical admixture has been tested and found to comply with the provisions of this specification using reference materials, and is being considered for use with other materials for specific work, additional tests for such use are allowed if agreed upon between the purchaser and the supplier and are allowed to consist of a portion of the tests described herein.

1.4 This specification provides for three levels of testing.

1.4.1 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 the section on Lot Uniformity and Equivalence shall be carried out to provide results against which later comparisons can be made.

1.4.2 Level 2 - Limited retesting described in the section relating to general requirements may be requested at intervals by the purchaser. Proof of compliance with the requirements of demonstrates continued conformity of the admixture with the requirements of the specification.

1.4.3 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 the section on Lot Uniformity and Equivalence shall be used.

1.5 The values stated in SI units are to be regarded as standard. The values in inch-pound units shown in parentheses are provided for information purposes only.

Note 1 - It is recommended that, whenever practicable, tests be made using the concrete-making materials (cement, pozzolan, slag, aggregates, air-entraining admixture), the mixture proportions, and the batching sequence and other physical conditions proposed for the specific work. The specific effects produced by chemical admixtures may vary with the properties and proportions of the other ingredients of the concrete.

Note 2 - Temperature has a pronounced effect on time of setting of concrete. This may be exaggerated by the use of admixture Types I and II. If concrete temperatures to be expected on a particular job differ significantly from the conditions set forth in this specification, further testing may be desirable.

Note 3 - An unusually rapid loss of workability with time, sometimes termed "slump loss", can be experienced with these admixtures. The rate of slump loss will vary with the particular concreting materials and proportions, mixing equipment and procedures, and temperatures experienced on any particular job. At elevated temperatures, the slump may be retained for a longer period if a Type II admixture is used.

Note 4 - 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 (see ACI 318).

Note 5 - Admixtures that contain relatively large amounts of alkali (Na 2O + 0.658 K2O) may contribute to reaction with some aggregates. Compliance with the requirements of this specification does not assure acceptability when used with alkali-reactive aggregates and some cements.

1.6 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.

The following precautionary caveat pertains only to the test method sections 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 practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

C33 Specification for Concrete Aggregates

C39/C39M Test Method for Compressive Strength of Cylindrical Concrete Specimens

C78 Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading)

C136 Test Method for Sieve Analysis of Fine and Coarse Aggregates

C138/C138M Test Method for Density (Unit Weight), Yield, and Air Content (Gravimetric) of Concrete

C143/C143M Test Method for Slump of Hydraulic-Cement Concrete

C150 Specification for Portland Cement

C157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete

C173/C173M Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method

C183 Practice for Sampling and the Amount of Testing of Hydraulic Cement

C192/C192M Practice for Making and Curing Concrete Test Specimens in the Laboratory

C231 Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method

C260 Specification for Air-Entraining Admixtures for Concrete

C403/C403M Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance

C666/C666M Test Method for Resistance of Concrete to Rapid Freezing and Thawing

C778 Specification for Sand

D75 Practice for Sampling Aggregates

D1193 Specification for Reagent Water

E100 Specification for ASTM Hydrometers

ManualofAggregateand

Keywords

admixture; concrete; flowing concrete; plasticizing admixtures; plasticizing and retarding admixtures; water-reducing admixtures; water-reducing and retarding admixtures;

ICS Code

ICS Number Code 91.100.30 (Concrete and concrete products)

Citing ASTM Standards

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