ASTM C1646/C1646M-16 PDF Download

The ASTM C1646/C1646M-16 standard provides guidelines for preparing and conditioning test specimens that can be used to evaluate the durability of coarse aggregate in air-entrained concrete. The standard references Test Method C666/C666M for conducting freezing and thawing tests.

The practice emphasizes the need for an adequate air-void system in concrete to enhance its resistance to freezing and thawing. However, it also highlights that even with proper air entrainment, if the coarse aggregate becomes critically saturated, the concrete may still be susceptible to damage. Critical saturation occurs when there is not enough pore space in the aggregate to accommodate the expansion of water during freezing.

The standard covers the procedures for making and curing test specimens using normal-weight coarse aggregates. It does not address all safety concerns associated with its use, and the user is responsible for establishing appropriate safety practices and determining the applicability of regulatory limitations. It also emphasizes the cautionary note that fresh hydraulic cementitious mixtures can cause chemical burns and require proper handling.