Analysis of Normal Consolidation of Viscous Clay

Abstract

A Theological model of the normal consolidation behavior of viscous clays is presented. The approach adopted combines elasto‐plastic behavior with structural viscosity effects. In particular, a modified Cam‐clay yield surface, employed to describe plasticity effects, is analyzed in conjunction with viscous resistance characteristics based on the use of a thixotropy law. The whole is placed in the context of Biot's two‐dimensional consolidation framework and solved using the finite element method. An application of the model, to the one‐dimensional consolidation of a clay that had previously been tested in the laboratory, is presented. Good correlation is achieved, indicating clearly the ability of the proposed model to reproduce real consolidation behavior during both the primary and the secondary phases. Various features of the model are then addressed via numerical predictions of the consolidation of thicker samples of the same clay. The model's scaling law is determined together with the form of the variation of deformation predictions, as drainage path lengths are increased. The importance of viscous resistance effects in the model's performance is also demonstrated.