Numerical modelling of Tunis soft clay

Abstract

The paper briefly reviews research investigations conducted on Tunis soft clay that is classified as problematic soil. Results obtained from an experimental study carried out on undisturbed Tunis soft clay specimens are presented and interpreted. On the basis of experimental results the paper discusses which constitutive law can describe at best the observed behaviour of Tunis soft clay? The elastoplastic behaviour modelled by the Hardening Soil Model (HSM) is then justified based on numerical simulation of oedometer and triaxial tests carried out on undisturbed soft clay specimens. Adopted parameters of the HSM model are considered to simulate the behaviour of geotechnical structures founded on Tunis soft clay using the finite element code Plaxis V9-2D and the FLAC3D code. The prediction of behaviour of two Tunisian case studies is analyzed: cylindrical oil tank on soft clay reinforced by sand columns and full pile loading. Comparison between predictions by the soft soil model (SSM) and HSM is presented.