Construction Technology Of Tunnel In Complex Geological Conditions

With the domestic large-scale investment in infrastructure construction, a large number of high-speed railway will be built in our country. During the planning and design in the high-speed railway, because of taking into account a large number of tunnels, it is very important that a lot of research on the railway tunnel construction technology need be done under different circumstances.Hainan is located in the tropical conditions, and the East-Central high-speed Railway construction includes a large number of tunnel project. In this paper, in order to enhance the construction skills in high-temperature tunnel under complex geological conditions, it adopts fuzzy comprehensive evaluation, numerical simulation and on-site monitoring method to study systematically the tunnel construction technology of high-temperature tunnel under complex geological conditions in terms of the tunnel construction program optimization, rock stress characteristics, construction method, on-site construction monitoring and information technology. The key technology in the project includes:(1)Combining the practical problems of Wenjianling tunnel of Hainan East-Central Railway construction, this article analyzed the impact of tunnel construction methods of the various factors, and described a variety of tunnel construction methods. According to the establishment of tunnel excavation's index system, the application of fuzzy mathematical method and the establishment of two fuzzy comprehensive evaluation model about on-site conditions of Wenjianling tunnel, and from the comprehensive evaluation of tunnel construction program,determined that the tunnel using ring cut method is optimal.(2)Through establishing an ideal elastic-plastic plane-strain model and ansys finite element software, numerical simulation for the construction process of Wenjianling tunnel were carried out, analyzed the changed characteristics of the surrounding rock stress field and displacement field, as well as supporting system pattern of the force. This paper examined the distribution of features and value differences in the various stages, and verified that the application of ring cut method is reasonable and feasible in tropical tunnel under complex geological conditions. (3)The Tunnel construction supporting technology in tropical tunnel under complex geological conditions was put forward. During the construction process,this paper further validated the Tunnel construction technology's reasonableness of Wenjianling tunnel through on-site monitoring of subsidence of the arch crown, horizontal convergence and surface subsidence, and so on.