ABSTRACT
The principles of compaction mechanics and the compaction model are covered. The objective of compaction is to improve the engineering properties of the soil mass. These benefits vary with the type of material being compacted. The quality control process involves assessing density ratio (DR) achieved after compaction. The aim is to reduce air voids. The DR is dependent on the thickness of the layer and its moisture content. The laboratory compaction model is the most important reference point, but may not be characteristic of the field condition. The compaction process in the field differs from that undertaken in the laboratory. Sample preparation and curing are mandatory as part of any test to avoid meaningless moisture-density test results. The compaction and California Bearing Ratio (CBR) tests require a maximum size to be applied with correction factors applied to adjust for these oversized particles. Two case studies are used to show the importance of sample preparation and representative sampling.
