Why is it important to maintain the moisture range in soil compaction?

Maintaining the appropriate moisture range in soil compaction is crucial for achieving optimal density. When soil is compacted, the goal is to reduce the voids between the soil particles, thereby increasing its density and strength. The presence of moisture plays a vital role in this process.

Water acts as a lubricant that allows soil particles to move closer together when subjected to compaction forces. If the soil is too dry, there is insufficient lubrication, and the particles do not bond effectively, resulting in lower density. Conversely, if the soil is too wet, excess water fills the voids and can prevent proper compaction, leading to a weaker structure once it dries.

By maintaining the moisture within a specific range, compaction machines can effectively compress the soil, achieving the density necessary for the stability of structures built upon it, such as roads, foundations, and retaining walls. This optimal density is crucial for ensuring longevity and strength in construction projects, as well as preventing issues such as settlement or erosion after completion.