Study On Influence Of Foundation Pile Construction On Deformation Of Adjacent Shield Tunnel

With the development of the city,the problems of the foundation piles adjacent to or intersecting with the subway tunnels have emerged.How to ensure the safety of adjacent tunnels during foundation pile construction has become an important research issue.In this paper,the large-diameter bored piles adjacent to the subway tunnel are used to monitor the pore water pressure near the pile,the displacement of the soil,and the deformation of the subway.The measured data are compared with subsequent theoretical calculations and numerical simulations.analysis.The safety problem of the full casing bored pile in the construction of the adjacent subway tunnel is explained,which provides reference for similar projects.The main work of this paper is:(1)Actual engineering monitoring and analysis.During the construction of bored piles,soil and pore water pressure monitoring during pile construction is carried out in a test facility such as pore water pressure gauge and inclinometer tube embedded in the soil adjacent to the pile;and deformation monitoring data of the subway tunnel during pile construction.Through the influence of pile construction on the surrounding pore water pressure and soil displacement,and the deformation of the tunnel,the effects of soil disturbance and pore water pressure on the deformation of adjacent subway tunnels were studied.(1)The research results show that in the case of cracks and water seepage in the subway tunnel,the method of constructing the full casing bored pile in the adjacent area meets the safety protection requirements of the tunnel.(2)Theoretical calculations.The sidewall pressure and end bearing force of the full casing bored pile are calculated,and the additional stress on the tunnel axis caused by the side wall pressure and the end bearing force is obtained.The deformation of the tunnel is obtained by calculating the additional stress on the tunnel axis by the energy variation method of the principle of minimum potential energy.It can be seen from the calculation results and measured data of this paper that the construction method of all-steel casing bored piles meets the protection requirements of subway tunnels beside the already operated subway tunnel.(3)Numerical simulation.The influence of the construction of the full casing bored pile on the adjacent tunnel was simulated,and the results of numerical simulation,theoretical calculation and actual measurement were compared and analyzed.The consistency was good.Figure[42]table[5]reference[62]...