How the subsoil conditions influence the choice of substructure?

Subsoil conditions such as soil type, compaction, and bearing capacity can affect the type and design of substructures. For example, soft or compressible soils may require deeper foundations or soil improvement techniques, while hard or rocky soils may allow for shallow foundations. It is crucial to assess the subsoil conditions to ensure the substructure is adequately supported and will perform well over time.