What is a characteristic of high plasticity soils?

High plasticity soils are characterized by their ability to retain moisture and their malleability when wet, which often gives them a sticky feel. This characteristic arises from the high clay content in these soils, which enhances their plasticity and ability to deform without breaking. When saturated, these soils can easily be shaped and molded, making the sticky texture a defining feature.

In contrast, very coarse-grained soils typically have low plasticity due to their larger particle sizes, which do not retain moisture in the same way. Soils with little to no shrink-swell potential generally possess low plasticity characteristics as well, meaning they do not expand or contract significantly with changes in moisture content, unlike high plasticity soils. Finally, high plasticity soils tend to have slower drainage capabilities due to their fine-grained structure, which can lead to water being retained rather than quickly draining away. Thus, the stickiness of high plasticity soils is a fundamental characteristic that reflects their composition and behavior under wet conditions.