What is the purpose of soil compaction in highway construction?

The purpose of soil compaction in highway construction primarily revolves around increasing soil density and stability, which is crucial for supporting the loads that will be applied by the roadway. When soil is compacted, the particles are pressed together, which reduces the volume of air gaps and increases the overall density. This densification leads to a stronger foundation that can withstand the stresses and strains generated by traffic, environmental conditions, and other dynamic loads.

A well-compacted soil base minimizes the risk of settling and shifting, thereby extending the longevity and safety of the roadway. Adequate soil compaction is vital for preventing issues such as cracking, deformation, and structural failure, which can arise if the underlying soil is insufficiently compacted. Therefore, the core reason for soil compaction is to ensure that the road can safely and effectively carry the anticipated loads over its lifespan.