The Stabiliy Influence Factor Analysis Of Rock Mass For Deep Tunnel In Fault Zone And Construction Scheme Optimization

Fault is a discontinuous structure which large rock strain energy is accumulated to a certain degree,The fault rock has poor integrity and low bearing capacity,the tunnel is easily caused to be the landslide in the construction process,Study on the stability factors and excavation construction scheme of fault tunnel can reduce the adverse effect of special geology on the stability of tunnel and solve the key problems in the design and construction of the fault zone which is in the deep buried tunnel,the study has a great engineering significance.This paper is based on the Shitang tunnel in Cangnan County,Zhejiang province.On the basis of a large amount of relevant literature data,we can analysis and study the above problem.(1)By using the finite difference software Flac3 D to simulate the construction process of the fault tunnel which is at different footage driving cycle,analyzing the deformation,the displacement release ratio and the plastic zone distribution of the surrounding rock in the same monitoring section,we can get the optimal cycle footage;At the same time,based on the optimal conditions of circulating footage,It is concluded that the influence of the fault width on the surrounding rock is different and provide reference for the same engineering or similar engineering.(2)By simulating the deep buried tunnel in the different construction schemes,analysing difference of the displacement and plastic zone of surrounding rock under different excavation schemes,understanding the weak link in the construction process of the fault tunnel,we can provide basis for scientific instruction.(3)Under different construction schemes,By comparing and analyzing the deformation and the stress release of surrounding rock which is in the tunnel,we can select the optimal reasonable construction scheme.This paper is based on the frontier of science,By using advanced numerical calculation and analytical method,we can study the stability factors and the optimization of tunnel excavation scheme of the fault tunnel.it provides an effective analytical method to study the stability of surrounding rock of deep buried tunnel with faults and has high engineering application value.