AN HARMONY MODEL OF ANISOTROPIC ELASTIC-PLASTIC DAMAGE FOR SATURATED ROCK

The research of anisotropic mechanical behaviors of rock is of importance; natural rock mass is anisotropic and its failing type is also non-isotropic. In this paper, an elastic-plastic damaged harmony model has been proposed; elastic deformation, damaged irreversible deformation and plastic deformation can be identified respectively. A second rank damage sensor is employed to characterize the induced damage; damage evolution is related to the propagation conditions of micro-cracks. A specific form of strain free energy is used to obtain effective elastic stiffness; the limited scopes of damage parameters are deduced. The determination of anisotropic parameters is proposed by virtue of a tri-axial laboratory test, and the mechanical behaviors of different loading paths are simulated. The comparison between testing data and numerical simulations yields similar results overall. The model is then used to simulate the coupled hydraulic mechanical responses in different loading paths. The numerical results also show the proposed model is suited to describe the main features of porous hydraulic mechanical behaviors of rock.