ASTM C128-15 pdf free download.Standard Test Method for Relative Density (Specific Gravity) and Absorption of Fine Aggregate.
1.1 This test method covers the determination of relative density (specific gravity) and the absorption of tine aggregates. The relative density (specific gravity), a dimensionless quality, is expressed as oven-dry (OD). saturated-surface-dry (SSD), or as apparent relative density (specific gravity). The OD relative density is determined after drying the aggregate. The SSD relative density and absorption are determined after soaking the aggregate in water for a prescribed duration.
1.2 This test method is not intended to be used for lightweight aggregates that comply with Specification C332 Group I aggregates.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 The text of this test method references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this test method.
1.5 This siaiidard does 110! 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 and health practices and determine the applicabilitv of regulatory limitations prior to use.
5. Significance and Use
5.1 Relative density (specific gravity) is the ratio of mass of an aggregate to the mass of a volume of water equal to the volume of the aggregate particles — also referred to as the absolute volume of the aggregate. It is also expressed as the rjtio of the density of the aggregate particles to the density of water.
5.2 Relative density is used to calculate the volume occupied by the aggregate in various mixtures containing aggregate including hydraulic cement concrete, bituminous concrete, and other mixtures that are proportioned or analyzed on an absolute volume basis. Relative density (specific gravity) is also used in the computation of voids in aggregate in Test Method C29/ C29M and in Test Method C1252. Relative density (specific gravity) (SSD) is used in the determination of surface moisture on fine aggregate by displacement of water in Test Method C70. Relative density (specific gravity) (SSI)) is used if the aggregate is in a saturated surface-dry condition, that is, if its absorption has been satisfied. Alternatively, the relative density (specific gravity) is used for computations when the aggregate is dry or assumed to be dry.
5.3 Apparent relative density (specific gravity) pertain to the solid material making up the constituent particles not including the pore space within the particles that is accessible to water. This value is not widely used in construction aggregate technology.ASTM C128 pdf download.