Property-dependent plastic potential theory for geomaterials

Aiming at the application defects of the traditional potential theory to geomaterials, caused by the basic assumptions such as continuity, homogeneity and isotropy, the property-dependent plastic potential theory for geomaterials is proposed by linking the strain distribution law with the material properties. The new theory is based on the physical properties in the microscopic aspects of sand described by the fabric with isotropic and anisotropic together. According to the proposed theory, the component direction of the plastic strain increment is consistent with that of the stress, but the value is the function of loading stress, degree of fabric anisotropy and geometric relationship between fabric and stress. Therefore the proposed theory can describe the anisotropic distribution of the plastic strain increment under the fixed principal stress and the values and direction of the plastic strain increment under the rotational principal stress. The energy conversion relationship is used to analyze the variation of the plastic strain increment. Compared with the existing non-coaxial plasticity theory, the proposed potential theory own a wider application and a clearer physical meaning.