Effects of using different constitutive soil models for the cavity expansion problem

Abstract

In this study it is aimed to investigate the changes in stresses, porewater pressures and displacements caused by the expansion of a cylindrical cavity utilizing different constitutive models. Boston Blue Clay is assumed as the soil surrounding a cavity and the behavior is analyzed through finite element modeling with Plaxis 2011 2D involving Modified Cam Clay (MCC), Soft Soil (SS) and Hardening Soil (HS) constitutive soil models. The results of axisymmetric numerical modeling are compared with the solution provided by Randolph et al. (1979a). While the changes of stresses and porewater pressures by the SS and HS models are reasonably acceptable, the results with the MCC model agree quite well with those provided by other researches. Moreover, the findings assuming a cylindrical cavity expansion are similar to the measurements of radial soil displacement around a cavity mid-depth in the field (Cooke and Price, 1973; Pestana et al., 2002) and in the laboratory model tests (Randolph et al., 1979a; Randolph et al., 1979b; Steenfelt et al., 1981) as well as the analytical solutions of cavity expansion.