Research On The Influence On Exisiting Multi-arch Tunnel Brought By Foundation Excavation Construction

With the continuous development of urban construction,the city land is also more and more tension,close to both carry out construction including building structures,including the deep pit will be difficult to avoid,such as urban deep excavation of the tunnel has been built near the security risks caused by the need to analyze possible judgment.In this paper,a project for the four Yunnan excavation support ways numerical simulation analysis,through its impact on the existing tunnel deformation than the election has been the best foundation bracing program,the influence of foundation pit excavation on the displacement and stress of the tunnel is simulated in detail.In this paper,the following problems are analyzed:(1)In view of the problem of foundation pit and tunnel,the mechanical model of the tunnel under the foundation pit and the mechanism of the failure of tunnel are introduced.Also,the paper introduces the working principle of the initial support and the tunnel lining of the tunnel.(2)The software named ANSYS is used to model the foundation pit without support,the pile retaining wall,the pile retaining wall and the steel tube support and the support of the underground continuous wall.According to the calculation results,the displacement and stress state of the tunnel are analyzed,and the optimal supporting method is selected according to the final state of the tunnel.(3)According to the optimal choice,using ANSYS software,foundation pit and the tunnel of the three-dimensional model is established,the detailed simulation of foundation pit excavation tunnel displacement should stress state,and plotted in graphs to analyze the variation tendency.