The traditional isotropic failure description of a self-similar loading surface exhibits severe limitations on depicting the loading-induced anisotropy. In this paper, an anisotropic formulation to model tri- axial behavior of concrete is presented in the framework of classical theory of…
The traditional isotropic failure description of a self-similar loading surface exhibits severe limitations on depicting the loading-induced anisotropy. In this paper, an anisotropic formulation to model tri- axial behavior of concrete is presented in the framework of classical theory of plasticity. For this purpose, a triaxial anisotropic loading function that distinguishes Mode I-dominated and Mode II-dominated behaviors is introduced in terms of three invariants. Two internal state variables associated with volumetric and deviatoric control the evolution of loading surface. For this purpose, total plastic strains are decomposed into volumetric and deviatoric components based on normality condition between the two components. As a conclusion, limi- tations of adopting isotropic formulation are addressed through numerical predictions of two non-proportional loading histories that are in inverse sequence.