Infuence And Protection Of Pile Foundation Of Adjacent Bridge With Subway Shield Construction

The research work of the paper is based on the project of Yuan-bo-yuan Station-Xing-jin Road Station of Metro Line One in Xiamen which shield through the Xinglin North Ring viaduct project,carried out the research work by means of theoretical analysis,numerical simulation and field monitoring.It puts forward the corresponding bridge pile foundation deformation prevention and control technology program.(1)Based on the original theory,the influence of various factors on the deformation caused by subway tunnel construction is analyzed.The results show that the displacement of the strata caused by the construction of the subway shield is mainly caused by horizontal displacement and vertical displacement,displacement deformation in different directions of the strata,so that different forms of deformation are produced in the adjacent pile foundation.The paper puts forward the prevention and control measures of the shield tunneling project and the deformation prevention and control standard of the project of side through of the Park Gyeongyuan Station～Xingjin Road Station.(2)Using Midas GTS software,the influence law of existing bridge pile deformation caused by shield construction is analyzed.It simulates and analyzes the protection effect of sleeve valve tube grouting.The simulation results show that the settlement of the formation and the deformation of the bridge pile are greatly reduced under the grouting reinforcement of the sleeve valve pipe,and the effect of the grouting pipe is obvious.The geogrids of 17.7m,20.7m and 23.7m length were used to simulate the soil layer,and the deformation of adjacent bridge piles was analyzed and compared.It concludes that 23.7m sleeve valve grouting reinforcement is more reasonable by comprehensive analysis of various factors.(3)Combined with the actual project,it develops the on-site construction deformation prevention and control monitoring program and analyzes the results of comparative prediction results and on-site monitoring.The results show that the ground subsidence of the simulated and predicted ground subsidence curve is basically same.After the casing pipe grouting and strengthening the formation,the surface subsidence and the deformation of the adjacent Xinglin Beihuan viaduct bridge are controlled within the allowable range.It ensures safety of the bridge during the construction of subway shield.