What characteristic is common among clay soils?

• A. Cohesionless and non-plastic
• B. Plastic and cohesive
• C. Weak and granular
• D. High permeability

Answer: (B)

Clay soils are typically characterized by their plastic and cohesive properties. This means that clay can change shape when subjected to stress, and it can also retain its shape when the stress is removed. The fine particles of clay are small and have a significant surface area, leading to high water retention and the ability to adhere together, giving clay its cohesive nature. This is vital for understanding its behavior in construction and engineering applications, as it affects how clay supports loads and interacts with water.

Plasticity is an important factor in clay because it enables the soil to deform under pressure rather than just fracturing. This property is pivotal in evaluating soil for various uses in construction, agriculture, and environmental engineering, as it influences factors like compaction, stability, and erosion resistance.

The other characteristics mentioned do not apply to clay soils. Cohesionless and non-plastic soils refer to materials like sands or gravels, which do not exhibit the same binding tendencies and are generally less stable under load compared to cohesive soils like clay. Similarly, weak and granular refers to materials that lack structural integrity and do not exhibit the same cohesive characteristics. High permeability is also not a defining trait of clay; in fact, clay typically has low permeability due to its dense particle arrangement, which restricts