Numerical Simulation to Research on the Fracture Mechanism of the Surrounding Rock in Deep Tunnels

In order to further explored the mechanical mechanism of surrounding rock zonal disintegration in deep buried tunnels, Numerical simulation was used in this paper to analyze the variation of different rock mass mechanical parameters (c, phi, mu) of surrounding rock and variation of the zonal disintegration under horizontal tectonic stress. Through the research and analysis, the influence law of rock mass mechanical parameters (c, phi, mu) on the zonal disintegration of surrounding rock of deep buried tunnel was obtained. The increase of the cohesive force and internal friction angle of the rock mass can reduce the range of partition failure. However, the influence of Poisson's ratio on the zonal disintegration range presents nonlinear characteristics. At the same time, the horizontal tectonic stress directly determines whether the zonal disintegration phenomenon occurs, and it is the key factor for the regional failure of the surrounding rock of the deep tunnel. The above conclusions had certain reference value for in-depth study of the failure problem in deep buried tunnels, and provided theoretical support for further discussion of its mechanical mechanism.