base course
Gravel beneath pavement
A base course is a foundation layer of material—usually gravel, crusite stone, or compacted aggregate—laid beneath a road, pavement, or building floor.
It distributes weight and provides drainage, sitting between the subgrade (raw earth) and the surface layer: The crew spread the base course before paving.
- subgradeSoil layer supporting pavement
- gravelLoose small rock fragments
- subbaseFoundation beneath a surface
- aggregateCombined sum total
- sandFine rock particles
compaction · soil compaction · load bearing · roadbed · crushed stone · foundation · stabilization · stone · macadam · frost resistance · layer · tamping · asphalt · roller · leveling · paving · structural integrity · civil engineering