In sand, what is the cohesion value?

In sand, the cohesion value is considered to be zero. This characteristic arises from the nature of granular materials like sand, which do not exhibit significant adhesive or intermolecular forces that would contribute to cohesion. Unlike clay, which has fine particles and can hold water, sand consists of larger, angular particles that mainly rely on friction for shear strength rather than cohesion.

Because of this property, when assessing the engineering behavior of sandy soils, it is common practice to apply the principle that cohesion is negligible. The assumption that cohesion equals zero is crucial in many geotechnical analyses, such as determining the bearing capacity of foundations or the stability of slopes.

While other choices present numerical cohesion values, they do not accurately reflect the fundamental properties of sand. By recognizing that the cohesion of clean, dry sand is effectively zero, engineers can better understand soil mechanics and design effective structures that account for the material's limitations.