Numerical simulation of the influence of structural planes to stability of tunnel surrounding rock

It is hard to avoid passing through the structural planes such as faults, joints and bedding planes in tunnel construction. All of these geological defects make a critical influence of the stability of underground excavations. Under actual condition, surrounding rock failure is difficult to be observed and studied. In this paper, RFPA(Realistic Failure Process Analysis), a numerical simulation software is used to study the instability and failure mechanism of tunnel surrounding rock under the influence of structural planes. Five faults at different position are tested in the simulation and the process of rock failure and the character of acoustic emission are recorded. The results show that when these models start to produce acoustic emission, these phenomena first generate at the position of fault. Since the presence of faults, deformation of surrounding rock will be different with the location of faults.