ASTM C685/C685M-17 PDF Download

The ASTM C685/C685M-17 standard specifies the requirements for concrete made by volumetric batching and continuous mixing. The standard outlines the quality requirements for the concrete and states that these requirements can be either as specified in the standard or as specified by the purchaser. If there is a difference between the purchaser's requirements and the standard, the purchaser's specifications will take precedence.

The standard does not cover the processes of placement, consolidation, finishing, curing, or protection of the concrete after delivery to the purchaser. It focuses on the tests and criteria for batching accuracy and mixing efficiency. The materials used in the concrete, including cement, aggregates, water, ground granulated blast-furnace slag, air-entraining admixtures, and chemical admixtures, must conform to the requirements outlined in the standard.

The standard provides additional procedures and cautions in an annex that are necessary when using existing test methods and practices to determine the uniformity of freshly mixed concrete. It explains the significance and use of the tests and requirements specified in the standard, which are used to evaluate loading and operating procedures, verify proportioning accuracy, and determine the degradation of mixing uniformity due to wear or accumulations of hardened concrete.