Stability Analysis of Surrounding Rock in Tunnel Crossing Water-Rich Fault Based on Catastrophe Theory

Abstract

The failure of surrounding rock in tunnel crossing water-rich fault is a sudden damage phenomenon with obvious nonlinear and abrupt characteristics, which is characterized by the uncertainty of deformation, the nonlinearity of constitutive relation and the mutation of failure process. Based on the mechanical model of tunnel-fault system, the cusp catastrophe model of the failure of surrounding rock in tunnel crossing water-rich fault is established. Combining with the field monitoring data, the model is employed to judge the stability of surrounding rock. Results show that the deformation curve of tunnel vault has a good correlation to the cusp catastrophe model, and the results for stability analysis is consistent with the actual situation. The influences that the strength of rock mass, groundwater and fault width have on the failure of tunnel are further discussed, which provides scientific guidelines to the construction of tunnel.