Swelling/Shrinkage Characteristic Curve of Desiccated Expansive Clays

The change in void ratio with change in water content of expansive clayey soils due to soil desiccation and water absorption has been identified as the integral/combined curve referred to as S-curve, which describes both swelling and shrinkage paths in the form of the void ratio versus moisture content relationship.

General characteristics of the S-curve and its determination procedure are described in detail in this paper, including presentation of the theoretical considerations, phase diagrams for both swelling and shrinkage conditions, and the primary paths of the S-curve.

The swelling/shrinkage characteristic curve in the form of the volume change versus moisture content relationship is also presented as a swelling potential chart that can be used to evaluate the swelling potential of desiccated expansive clays.