Modeling and Testing for Anisotropic Behavior of Soils

A rate‐independent elastoplasticity constitutive model is developed to account for various factors, such as friction, stress path and history, and induced and initial anisotropy in the response of geological materials. A hierarchical approach is adopted whereby models of progressively increased sophistication are developed from a basic isotropic hardening associative model, with the concepts of anisotropic hardening and nonassociativeness, and a new measure to define anisotropy and deviation from normality. Both anisotropic hardening and deviation from normality are defined by using a second‐order tensor, whose evolution is governed by the level of induced anisotropy. The concepts used in the development of the model and the predictive quality of the model are verified with respect to special multiaxial tests with cubical specimens and conventional triaxial tests with cylindrical specimens of three different sands.