ASTM C127-15 PDF Download

ASTM C127-15 is a standard test method that determines the relative density (specific gravity) and absorption of coarse aggregates. Relative density is the ratio of the mass of an aggregate to the mass of a volume of water equal to the volume of the aggregate particles, and it is also expressed as the ratio of the density of the aggregate particles to the density of water. This test method distinguishes between the density of the aggregate particles and the bulk density of aggregates, which includes the volume of voids between the particles.

The relative density is used to calculate the volume occupied by the aggregate in various mixtures, such as hydraulic cement concrete and bituminous concrete. It is also used in the computation of voids in aggregate. The test can be conducted using the saturated-surface-dry (SSD) condition, where the aggregate has reached a state of saturation without any excess water, or using the dry condition.

The standard also includes the determination of absorption values, which measure the change in the mass of an aggregate due to water absorbed in the pore spaces within the particles. Absorption is important for understanding the moisture content of the aggregate and its potential impact on the properties of the mixture in which it is used. The absorption values are typically determined after submerging the dry aggregate for a specified period of time.

It should be noted that the absorption values obtained through different test methods may vary, depending on the conditioning of the aggregate. The standard provides general procedures that are suitable for determining absorption with other conditioning methods, such as boiling water or vacuum saturation.

This test method applies to coarse aggregates, but it is not intended for use with lightweight aggregates that comply with specific requirements outlined in Specification C332. The standard also includes explanatory notes and footnotes that provide additional information but do not impose any additional requirements.