An Elastic-Plastic Constitutive Relation for Transverse-Isotropic Three-Phase Earth Materials.

摘要

This report documents the development of a three-dimensional, elastic-plastic work-hardening constitutive model for transverse-isotropic three-phase earth materials. This model can be used to perform effective stress analyses for boundary value problems involving fully- or partially-saturated earth materials. Within the elastic range, the model contains three dimensionless parameters and two response functions. Within the plastic range, on the other hand, it contains three dimensionless parameters and three potential functions. It is shown that the numerical values of the dimensionless elastic and plastic parameters as well as the values of the coefficient in the response and potential functions can be determined experimentally using essentially conventional laboratory testing techniques. It is also shown that the model readily reduces to its isotropic counterpart without any changes in its basic mathematical functions. The model is capable of simulating the drained and undrained behavior of typical earth materials subjected to both spherical and deviatoric states of stress. For undrained applications, it predicts the effective stresses as well as the pore pressure.