Characteristics of deformation and permeability of fractured rock

It is especially important to reach the characteristics of deformation and permeability of fractured rock for the stability analysis in the rock mechanics. Many studies have been done on the failure condition of rock-like materials and the post-failure behavior of rock has been investigated using the various types of stiff compression testing machines. However, it is very difficult to explain systematically the characteristics of deformation including the failure condition and the post-failure behavior such as the strain hardening and softening obtained by the experiments based on the theory of elasto-plasticity.