1. Scope

1.1 This specification covers materials for use as anti-washout admixtures to be added to hydraulic-cement concrete mixtures for the purpose of minimizing washout of cement and other fine fractions of materials from concrete being placed under water. 1.2 This specification stipulates tests of an anti-washout admixture with suitable concreting materials. Unless specified otherwise by the purchaser, the tests shall be made using concreting materials. 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 demonstrates that the admixture meets the requirements of this specification. The basic approach of this level of testing is to compare critical properties of concrete containing the anti-washout admixture, dosed at levels required to provide a specified level of anti-washout performance, with the same properties of the reference concrete. 1.3.2 Level 2-Limited retesting. Proof of compliance with the requirements of Table 4 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 purchase, the uniformity and equivalence tests of Section 17 shall be used. 1.4 Units--The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. Some values have only SI units because the inch-pound equivalents are not used in practice. Note 1-Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size. 1.5 The text of this standard references notes and footnotes that 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 procedures and test methods in Sections 13-15 of this specification: This standard does not purport to address all of the safety concerns, is 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. (WARNING Fresh hydraulic cementitiousmixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)

Keywords

admixtures; concrete; performance requirements; anti-washout; underwater placement

Rationale

This specification will be used to qualify admixtures as being suitable to reduce the loss of fine particles from concrete being placed underwater without having any significant adverse effects on normal concrete properties.

The title and scope are in draft form and are under development within this ASTM Committee.