A coupled elasto-plastic-damage mechanical model for marble

A profound understanding of the mechanical behaviors of marble is very important for the design and construction of deep diversion tunnels in Jinping II hydropower station. In this paper, a coupled elasto-plastic-damage mechanical model is presented for Jinping marble. Firstly, the experimental investigations on Jinping marble are summarized. Then, based on the framework of continuum damage and plastic theories, a general mechanical model is proposed to predict the mechanical responses of Jinping marble. The proposed model is used to simulate the triaxial compressive tests, and there is a general good agreement between experimental data and numerical predictions in a qualitative manner. The proposed model is able to capture the main features of Jinping marble observed in experiments, such as progressive yielding process, damage induced by plastic distortion, dilation, elastic degradation and stress sensitivity.