The Construction Of Shield Tunneling Subway Tunnel Protective Measures

With the increase of China's investment in the construction of subway,subway construction in the major city like a raging fire,because of the particularity of the subway construction,in the construction process will appear all sorts of diseases,caused by the excavation of the subway formation process of stress and strain the disturbance caused by the most prominent problem,formation caused by disturbance force the strain will inevitably affect the security and stability of the ancient architecture.On line 2 of Xi'an metro shield tunnel construction across the walls-Tower-North Street engineering as the research background,through the combination of theory and practice,taking Xi'an as the actual characteristics of loess,based on soil mechanics theory,the surface caused by shield tunnel construction deformation and instability mechanism analysis,the control process of shield tunneling induced the surface settlement of shield tunnel construction in the key is to reduce the surface settlement caused by the construction and surface subsidence caused by the analysis and summarize the results of the numerical simulation,according to the specific conditions of Xi'an Metro Line 2,the use of numerical methods for solving,thus making the main factors affecting the surface settlement of shield excavation face;force formula is derived,and puts forward the protection of ancient buildings;find out the key control factors in the protection of ancient buildings,according to the process of opening advance of shield The analysis of the stability of the excavated surface soil and the reasonable calculation formula of the shield driving force obtained by this paper,and puts forward the technical scheme of the protection of the moat in the shield construction.The soil above tunnel to tunnel through the ancient city wall of the grouting reinforcement measures the parameters of soil mechanics performance enhancement,effectively control the surface subsidence and the walls;in the vicinity of the tunnel construction to the front of the bell tower on the tower base is provided with a peripheral ring of rotary drilling pile by rotary drilling pile to reinforce the stratum partition at the same time,the protection of grouting pile of tower.Through the above protection measures to ensure the protection of ancient buildings in the tunnel shield construction process,the research results are applied in practice,and the engineering application is summarized for reference.Through the subway tunnel construction to take effective measures to control the ground settlement,to ensure that no damage to the ancient buildings and security risks.