Definition : Standardized test to determine the compaction characteristics of a soil or granular material for a given level of energy applied.
1. The test consists in preparing specimens with different moisture contents and then compacting them according to a specified procedure. The dry density and moisture content of each specimen are determined.
2. The standard and modified Proctor tests differ in the parameters that define compaction energy (moulds and tampers used, number and thickness of layers compacted).