Role of Water in Compaction Of Soil
Water plays an important role in compaction. When water is added to dry soil, the soil grains get surrounded by a film of absorbed water.
If more water is added, then this becomes thicker and soil grains surrounded by such films can slide over each other more easily.
The grains thus become capable to occupy closer spacing more easily on the application of external loading. The water thus acts only as a lubricant in the compaction process and closer packing of soil grains is achieved on rolling by the expulsion of air from the voids.