Rock failure mechanism and true triaxial experimental study of specimens with single structural plane under three-dimensional stress

Aiming at brittle failure of rock with structural plane, single structure plane controlling effect under three-dimensional stress is studied and verified by true triaxial experiments. The mechanical characteristics, structure controlling laws and acoustic emission (AE) characteristics of rock specimens with single structural plane is studied systematically, simulating the excavating and supporting stress path in engineering practice. The research indicates: (1) Single structure plane controlling effect under three-dimensional stress can describe the structure controlling laws, unloading and supporting effect of engineering rock well. True triaxial experiment results conform to the theory. (2) Under excavating and supporting stress path, the failure mode, unloading and supporting effect are all connected with stress condition, supporting strength and structural parameters. Therefore, methods as engineering orientation arrangement and proper support can be taken to prevent structure controlling failure. (3) The AE features and energy release laws are similar with intact specimens. However, the existence of structure reduces the strength and energy storage capability. Also, 95 % of the elastic strain energy is released during failure stage. The research can guide the excavation and supporting of engineering rock mass.