Cohesion 

           cohesion is the internal molecular attraction which resists rupture or shear of a material. Cohesion is derived in fine-grained soils from the water films which bind together the individual particles in the soil mass. Cohesion is the characteristic of the fine materials with particles size below about 0.002 mm (clay).

The cohesion of a soil decreases as the moisture content increases. Cohesion is greater in well-compacted clays than in badly compacted soils and is independent of the external loads applied