Research On The Construction Technology Of The Metro Hole In The Mountain City

ABSTRACT:As more and more people pay attention to environmental protection, how to reduce damage to the environment and the stability of slopes caused by excavation of the subway hole in the mountain city become an urgent problem. Using the traditional open cut excavation method in the hole of the tunnel will inevitably damage the surrounding natural environment. And there will always be some buildings above subway, which limits the excavation of the slope. Even if the slope can be excavated, disturbance caused by excavation of rock will impact on the surrounding buildings.In order to reduce damage to the environment as well as slope stability and the buildings on the slope, this paper selects a new excavation method of the tunnel hole. This paper summarizes the entrance tunnel excavation method, method of advance support hole. According to Chongqing Metro Line 6, this paper compares open-cut method with cover excavation method. By ANSYS finite element software, this paper analyses the effect of the two excavation methods on slope stability and the size and scope of rock deformation. The development trend of rock deformation and failure mechanism of rock are analyzed in the process of the entrance tunnel excavation. The two excavation methods are compared from the aspects of environmental protection, economy, technology. Finally, on the basis of the above, this paper analyses the mechanism of the cover excavation method and summarizes the construction technology of the cover excavation method.Building subway in the scenic area and the mountain city, the cover excavation method is important for the entrance tunnel excavation.