ANALYTICAL VOLUME CHANGE MODEL FOR SWELLING CLAY SOILS

Swelling clay soils undergo volume changes as the moisture content var ies. This volume change is typically described by a shrinkage characte ristic curve. There is a need for a generally acceptable model to desc ribe these curves without requiring extensive soil shrinkage measureme nts. Models that are presently available in the literature do not repr esent the shrinkage characteristic curve data adequately and, thus, ha ve limitations to their application. We have developed an analytical v olume change model that was derived using the theoretical boundary con ditions at the endpoints of the four shrinkage ranges. Thus, the model describes all four shrinkage ranges better without additional input r equirements. The proposed model describes a smooth shrinkage character istic curve with continuous slopes at the endpoints of each shrinkage range. The analytical model was verified against measured shrinkage ch aracteristic curves and was found to represent the data very well.