Ground filling, also known as earth filling or soil filling, is the process of placing and compacting earthen materials in trenches, foundations, and under floors to fill in holes or depressions.
The materials used for ground filling can include:
- Sand: A popular choice for backfill work because it's inexpensive and compacts well
- Gravel or crushed stone: Used in granular filling to support structures and fill voids
- Fly ash and slag: Commercial by-products that can be used as backfill materials
- Controlled Low-Strength Material (CLSM): Also known as flowable fill, this material is a mixture of Portland cement, fly ash, fine aggregate, and water
Here are some tips for ground filling:
- Avoid large chunks of soil in the filling
- Sprinkle water carefully so it doesn't turn to mud
- After compaction, send a soil sample to a lab to check the proctor value
- For soil earth filling, achieve 90% density
- For loam earth filling, achieve 90–95% density
- Perform core cutting and sand replacement tests to check compaction quality
