Study On Settlement Deformation And Safety Control Of Metro Shield Tunnel Crossing High-rise Buildings

The development of rail transit(subway)has become an important measure to alleviate the urban congestion.The subway lines are usually planned in densely populated areas.It is inevitable for the subway lines to cross the existing buildings.Therefore,the ground settlement and deformation caused by the subway tunnel construction has become the focus of the engineering and technical personnel.The research on the subway tunnel crossing the adjacent buildings Settlement and deformation of buildings and safety control measures are of great significance.Taking "Wenjing Road Station Fengcheng nine road station section of Xi’an Metro Line 4" as the project background,this paper focuses on the subject "Research on settlement deformation and safety control of metro shield passing through high-rise buildings group",and adopts the method of theoretical analysis,field monitoring and numerical simulation to study the law of stratum settlement deformation and uneven settlement of buildings caused by metro shield construction This paper analyzes the safety control measures of metro shield passing through high-rise buildings.The main research contents and conclusions are as follows:(1)Fully investigate the general situation of supporting projects,including engineering geology,hydrogeology,the situation of Shield Crossing buildings and the use of important buildings,and analyze the mechanism of ground deformation caused by shield construction.(2)According to the situation of the shield tunnel crossing the building,the field monitoring and analysis of the settlement and deformation are carried out.The tracking monitoring results of the ground surface and the building settlement and deformation show that the settlement control of the left and right lines is good during the crossing of the high-rise building,and there is no settlement warning value,in which the maximum ground settlement caused by the left line passing through the building is 7.46mm;the ground settlement caused by the right line passing through the building is 7.46 mm The maximum settlement is 7.6mm;the settlement value is concentrated within 5mm.(3)The results of two-dimensional and three-dimensional numerical calculation are consistent,and the deformation law of stratum settlement is basically consistent with the measured data,and the internal force of shield calculated by two-dimensional calculation is close to the internal force of segment calculated by stratum structure model;the numerical calculation results show that the maximum settlement of raft is about 17 mm after the excavation of right line tunnel,about 22 mm after the double line tunnel is through;the maximum settlement of raft is about 22 mm The drop is about 19 mm,and the inclination is 0.05%;it can meet the requirements of building settlement and inclination when added with the existing deformation.(4)According to the plane line and underpass condition of the tunnel,select the test section,reasonably select the shield tunneling parameters of the test section,and further develop the tunneling scheme and control measures for the shield tunneling through the buildings;based on the analysis of the settlement mechanism of the shield construction,combined with the field test and the actual excavation situation,give the reasonable synchronous slurry mix ratio at different positions of the shield interval;metro shield The settlement and deformation of the underground high-rise buildings are effectively controlled.