Simulating Seasonal Ground Movement in Unsaturated Clay

Abstract

The results of a theoretical, experimental, and numerical investigation into the volume‐change behavior of an unsaturated clay are described. The theoretical approach adopted is presented and its implementation detailed. The work is shown to be analogous to Terzaghi's classical theory of one‐dimensional consolidation for saturated soils. An experimental procedure is proposed for the determination of appropriate one‐dimensional soil properties. The procedure is used to determine the variation of volumetric strain and volumetric moisture content with respect to capillary potential for the Kimmeridge clay under consideration. The experimental results achieved are used to obtain deformation moduli that are applied in a simulation of seasonal ground movement. In particular, ground movements corresponding to previously determined moisture‐content variations over the 1983 period are predicted. The results of the numerical simulation are assessed qualitatively and quantitatively by comparison with field‐measured data. The approach adopted is concluded to be capable of producing realistic predictions of seasonal ground movement.