ABSTRACT
During dry seasons, the natural water content is practically zero on the surface and the volume of the soil reaches the shrinkage limit. The water content increases with depth and reaches a value W n at a depth Dus' beyond which it remains almost constant. During the wet season the water content increases and reaches a maximum at the surface. The water content decreases with depth from a maximum of W n at the surface to a constant value of W n at almost the same depth Dus. This indicates that the intake of water by the expansive soil into its lattice structure is a maximum at the surface and nil at depth Dus. This means that the soil lying within this depth Dus is subjected to drying and wetting and hence cause considerable movements in the soil. The movements are considerable close to the ground surface and decrease with depth. The cracks that are developed in the dry seasons close due to lateral movements during the wet seasons.
