ASTM C 31/C31M : 2026 : REV A

1.1This practice covers procedures for making and curing cylinder and beam specimens from representative samples of fresh concrete for a construction project.

1.2This practice is not intended for making specimens from concrete not having measurable slump or requiring other sizes or shapes of specimens.

1.3This practice is not applicable to lightweight insulating concrete or controlled low strength material (CLSM).

1.4This practice requires modifications if testing Ultra-High-Performance Concrete (UHPC).

1.5The 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 non-conformance with the standard.

1.6 The text of this standard refers to notes and footnotes and includes discussions of definitions that provide explanatory information. These shall not be considered as requirements of the standard, except for notes and footnotes in figures and tables.

1.7This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to exposed skin and tissue upon prolonged exposure.)

1.8This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.