The HM-375 Relative Compaction Test Set is used for laboratory determination of the maximum wet density of soils and aggregates by the California impact method. Relative compaction is the ratio of in-place wet density to test maximum wet density of the same soil or aggregate. In-place wet density is determined in the field using sand volume apparatus.
A 10lb (4.54kg) tamper is dropped from 18in (457mm) to compact samples to about 10—12in (254—305mm) in a 36in (914mm) long, 2-7/8in (73mm) diameter split mold. The special steel mold has a removable base and three hinged clamps for easy sample removal. Also included in the set are a metal leveling piston and a piston handling rod. Density is easily determined after compaction, based on a reading from the graduated scale on the shaft of the tamper. HM-375 is designed for manual use only.