Numerical Simulation Of Loess Highway Tunnel Construction Process

With the rapid development of traffic infrastructure construction in recent years, there built a large number of tunnel engineering in loess area. Many of them are railway tunnels, at the same time, there were a lot of highway tunnels. As the loess possess weak engineer properties, there exists many problems in design and construction of tunnel in loess geological conditions. In the process of urban tunnel construction, it is inevitable to go through some of the facilities, then higher requirements were put forward in the design and the construction of tunnel. As the loess engineering properties have diversity in various regions, at the same time, there lack experience of design and construction of highway tunnel in the loess, it is necessary to conduct further research.Based on the example of loess highway tunnel through transportation Line for coal in Lanzhou, the paper analyses the geological features of the tunnel engineering and the surrounding rock variation characteristics of excavation surface, then built finite element model by ANSYS to simulate construction environment and construction method of the tunnel. Through the analysis of surrounding rock stress change and rock deformation of different construction stage, summed up the law, and then pointed out the problems that should be paid attention in the construction process, finally put forward the guiding opinions.