Finite element analysis of the stability of a vertical cut using an anisotropic soil model

Abstract

A finite element (FE) analysis of the field test excavation in Welland Clay is performed using an anisotropic soil behavior model. This paper describes the model, FE formulation, and transient effective stress stability analysis, and compares FE results with the field measurements. The analysis reflects the postexcavation decrease in the factor of safety with time and predicts the failure of the slope along the observed failure surface. The parametric study shows that the time to failure is a function of the pore pressure boundary conditions at the excavation surface and affects the transient factor of safety. Key words: constitutive relations, excavations, finite element, plasticity models, pore pressure, soil anisotropy, stability.

Analysis of Cylindrical Cavity Expansion in Modified Cam Clay with $$ Ko $$Ko Consolidation

“…If either the initial stress state or the clay fabric, or both, are anisotropic, or if the soil is overconsolidated, better models should be resorted to, for example, such as the anisotropic Modified Cam Clay model (Dafalias 1987;Dafalias et al 2002Dafalias et al , 2006 or the Banerjee model (Banerjee and Yousif 1986;Banerjee et al 1988). These two models have the advantage over more sophisticated and complex models that they can account for both inherent and induced anisotropy with relatively few model parameters.…”

Plastic anisotropy of soft reconstituted clays

“…The changes in anisotropy due to plastic straining are represented by changes in the inclination (or position) of the yield surface according to so-called rotational or kinematic (translational) hardening laws. In these hardening laws, the changes in the anisotropy are commonly assumed to be caused by either plastic volumetric strains only (e.g., Banerjee and Yousif 1986;Dafalias 1986;Davies and Newson 1993;Whittle and Kavvadas 1994) or plastic shear strains only (e.g., Nova 1985;Banerjee et al 1988). However, both plastic volumetric strains and plastic shear strains are changing the arrangement of particles and particle contacts, and consequently are likely to contribute to the evolution of anisotropy.…”