What term describes the increase in volume of dirt after excavation?

The term that describes the increase in volume of dirt after excavation is "swell." When soil is excavated, it tends to expand due to the disturbance of its structure. This phenomenon occurs because the particles that were compacted together in the ground are now loosened and can occupy more space. Swell is especially significant in cohesive soils, such as clay, where the soil can hold onto water or air, leading to a significant increase in volume once disturbed.

Understanding swell is important in construction and earthwork projects, as it affects the amount of fill needed, the stability of structures built on or near excavated areas, and the overall planning of excavation operations. It's crucial for builders to account for swell in their calculations to avoid unexpected issues regarding soil volume and behavior after excavation is performed.