Study On The Influence Of Deep Foundation Pit Construction Of Jinan Metro Station On A Djacent Buildings

With the rapid development of society,the construction of metro in major cities is in full swing.During the construction of the deep foundation pit of the metro station,it was easy to affect the adjacent buildings,which will caused damage to the building.In order to study the effects of the deep foundation pit dewatering and construction process on the adjacent buildings at the metro station,this paper taken the deep foundation pit engineering of a station in Jinan Metro as the background.The finite difference software FLAC3D was used to establish a three-dimensional numerical calculation model for the deep foundation pit and building refinement of metro station considering fluid-solid coupling.The displacement,supporting axial force,nearby surface settlement,building deformation and stress variation characteristics of the deep foundation pit retaining structure of the metro station were analyzed,and the measured data were compared.The specific research results were as follows:(1)When the deep foundation pit excavation was not applied as a horizontal support,the horizontal deformation curve of the pile body has a "horn shape" curve.With the increase of the excavation depth of the foundation pit and the application of the horizontal support,the pile body curve had an obvious parabolic shape.(2)With the increase of the excavation depth of the foundation pit,the settlement speed of the soil within 20m from the edge of the foundation pit increased rapidly.When the deep foundation pit excavation was not applied as a lateral support,the surface settlement curve was similar to a triangle.When the lateral support was erected,the surface settlement curve gradually changed to a groove shape,and the lateral support had a great influence on the ground settlement curve and the horizontal deformation of the pile body.(3)During the construction of the foundation pit,the first and second lateral supports bear large axial stress,which limited the horizontal displacement of the pile top.The axial stress of the third and fourth lateral supports was always smaller than the axial stress of the first and second supports,which was related to the horizontal displacement of the enclosure.(4)The construction of the deep foundation pit caused a certain degree of uneven settlement in the adjacent building,and the building was slightly inclined,but it was always in a safe state.The soil body affected by the seepage flow outside the pit was about 50m away from the edge of the foundation pit,which was 2?3 times the width of the foundation pit.The part of the adjacent building was within the influence of seepage.