An Anisotropic Critical State Plasticity Model with Stress Ratio-Dependent Fabric Tensor

Abstract

This paper proposes a new constitutive model within the recent anisotropic critical state theory (ACST) to take into account the influence of evolving fabric on the stress–strain–strength response of anisotropic sands. Analytical proofs in support of stress–force–fabric correlations corroborate a clear connection between mobilization of the continuum level stress ratio and particle level fabric in granular media. A normalized stress ratio-dependent second-order fabric tensor is suggested here which fulfills the ACST. Dilatancy and plastic hardening modulus of a stress ratio-driven elastoplastic model with zero pure elastic domain are explicitly interrelated to the proposed stress ratio-dependent normalized fabric tensor. It is shown that the fabric-dependent model simulations agree well with the monotonic triaxial and hollow cylinder torsion shear tests data.