ANALYTICAL VOLUME CHANGE MODEL FOR SWELLING CLAY SOILS

Swelling clay soils undergo volume changes as the moisture content varies. This volume change is typically described by a shrinkage characteristic curve. There is a need for a generally acceptable model to describe these curves without requiring extensive soil shrinkage measurements. Models that are presently available in the literature do not represent the shrinkage characteristic curve data adequately and, thus, have limitations to their application. We have developed an analytical volume change model that was derived using the theoretical boundary conditions at the endpoints of the four shrinkage ranges. Thus, the model describes all four shrinkage ranges better without additional input requirements. The proposed model describes a smooth shrinkage characteristic curve with continuous slopes at the endpoints of each shrinkage range. The analytical model was verified against measured shrinkage characteristic curves and was found to represent the data very well.