ASTM C172/C172M-17,Standard Practice for Sampling Freshly Mixed Concrete.
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ASTM C172/C172M-17 covers procedures for obtaining representative samples of fresh concrete as delivered to the project site on which tests are to be performed to determine compliance with quality requirements of the specifications under which the concrete is furnished (Note 1).
ASTM C172/C172M-17 also covers the procedures to be used for preparing a sample of concrete for further testing where it is desirable or necessary to remove the aggregate larger than a designated size.
Sampling
The elapsed time shall not exceed 15 min. between obtaining the first and final portions of the composite sample.
Transport the individual samples to the place where fresh concrete tests are to be performed or where test specimens are to be molded. They shall be combined and remixed with a shovel the minimum amount necessary to ensure uniformity and compliance with the maximum time limits specified in 4.1.2.
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