Which of the following materials is typically used as fill when backfilling?

The use of crushed stone as fill material when backfilling is preferred for several reasons. Crushed stone offers excellent drainage properties, which can help prevent water accumulation in the backfilled area. This is important to maintain soil integrity and reduce the risk of erosion or settlement over time.

Additionally, crushed stone provides good compaction characteristics, which contribute to stability and support for structures built on or around backfilled areas. Its angular shape allows the particles to interlock effectively during compaction, creating a denser and more stable fill than some other materials might achieve.

In contrast, wet clay can retain water, leading to potential swelling and reduced strength when wet. Granite, while stable, is not typically crushed or used for backfill due to its density and cost considerations. Loose sand, although it can be used for fill, does not provide the same compaction and stability as crushed stone, particularly in maintaining structure support. Thus, crushed stone stands out as the material of choice for backfilling due to its overall performance and reliability in construction projects.