Research On Deformation Characteristics Of Shield Tunnel Cross The Viaduct Pile Foundation

With accelerating the pace of urbanization in the modern city, traffic congestion, environmental pollution, and crowded space becomes a serious problem in city, hindering the further development of the city. Gradually, MTR represented urban rail transit with many advantages won people’s favor, eases the traffic congestion of this city. Due to the early planning and construction of the city, the new line will pass through large number of existing buildings and bridges inevitably. Now, many subway construction methods are shield tunnel construction method, and when the disturbance to the ground and the adjacent pile foundation, which will bring hidden trouble to the normal use of the bridge. In order to reduce the interference of the shield tunnel construction of viaduct pile foundation, ensure the driving safety, reduce the risk of engineering construction is important guiding significance.In this paper, on the basis of the domestic and foreign scholars’ study, combined with the Wuhan Metro Line first project of Laoguan village station to Bolan center station interval shield tunnel crossing the viaduct of the Sixin road as example. Using the FLAC^{3 D} finite difference software to establish the simulation model, calculating different working conditions, the deformed analysis on influence of shield tunnel through the ground and viaduct pile foundation, summarizing the relevant laws of the deformation of the ground and viaduct pile foundation, hoping to provide some reference and help for engineering design and construction. The main research contents of this study are as follows:（1） Combined with the literature at home and abroad, and analyzed the research direction of this thesis research and information research, summarized the core content of the system involved in the engineering problems of shield tunnel. To discuss the deformed mechanism and the influence of shield tunnel crossing the ground and viaduct pile foundation.（2） According to the actual project, with the numerical simulation method, establishing a numerical model by finite difference software of FLAC^{3 D}. With different excavation distance for different process step by step calculation, combined with software’s simulation data, calculating the process to analyzing deformation of shield tunnel crossing the ground and viaduct pile foundation.（3） With reference to the correctness proof of numerical simulation results by relevant specification and a large number examples of engineering experience, the calculated results fit the deformation curves of the ground and pile foundation, summarizes the controlling focus on the ground and the protection of deformed characteristic of the viaduct pile foundation when shield tunnel crossing through.