The compaction process

Compaction is the process by which soil particles are forced together by reduction of the air voids content. It has the following effects on most materials when compared with their loose state:

Soil or rock fill comprises three components or phases:

The classic vehicle for understanding the relationship between these three phases is the phase diagram (Figure 2.1). From this diagram, certain important relationships can be written down and the following formulae derived.

where w is the water (moisture) content, G_s is the specific gravity of the soil and e is the void ratio.