Abstract:The rock of underground engineering in the colliery is bedded. Because of the bedded strata it has much difficulties in the mechanical analysis of the engineering rock. Based on the actual needs of the engineering,every stratum of layered rock structure can be regarded as the homogeneous and isotropic elastic body. But the layered rock structure itself is discontinuous and heterogenous. By analysis and calculation,the equivalent medium is found to substitute for the layered rock structure. A simple and convenient method is provided for studying mechanical behavior of layered rock at a different angle of the engineering rock mechanics.