Which soils generally compact the easiest?

Granular materials are typically the easiest to compact due to their physical properties. These materials often consist of coarse particles such as sand and gravel, which have larger sizes and better interlocking capabilities. When subjected to compaction forces, the voids between the larger particles can be effectively filled, and the air is expelled from the spaces, leading to an increase in density.

The nature of granular materials allows for the movement of particles, which facilitates effective compaction as they can rearrange and settle into a denser configuration. This is especially true when moisture is added, as it helps lubricate the particles, making it easier for them to settle together while preventing the structure from becoming too wet and losing its ability to compact.

In contrast, other types of soils, such as clay, tend to become hard and require more force to compact due to their smaller particle size and cohesion properties. Silty soils can also be tricky to compact effectively due to their plasticity and tendency to retain water. Organic soils, on the other hand, contain decomposed plant material, which can lead to lower strength and higher compressibility, making them more difficult to compact efficiently compared to granular materials.