Influence of Deep Foundation Pit Excavation on Adjacent Buildings under Unfavorable Geological Conditions of Deep Silt Soil

In coastal area, there are many muddy soil layers with high compressibility, rheology and thixotropy bad engineering geological properties. Therefore, the deep silt soil deep excavation is facing high risk construction and has significant effects on the surrounding environment. In order to further clarify the deep silt soil mechanical excavation of significant effect, based on a deep foundation pit project, through the finite element three-dimensional numerical simulation, the influences of silt soil deep excavation on nearby architectural structures are revealed. The results show that: the existence of deep silt soil makes the horizontal influence area of the foundation pit excavation increase obviously, while the vertical influence area is less affected. In the horizontal distance of 150 m and the depth of 85 m, the soil and structures are all affected by the foundation pit excavation. Foundation pit and outline in concave and convex, architectural structures, discover stress concentration. Therefore, in the land of silt soil layer depth, wall and both the horizontal displacement of tunnel wall panel with obvious mutation; both the horizontal displacement and settlement curve tunnel is the characteristics of the "large in the middle and small at both ends". The deformation of the bridge increases with the increase of the excavation depth and the horizontal displacement of the bridge piles in the silt soil depth increases obviously with the maximum horizontal displacement of 5.33 mm and maximum subsidence of 9.92 mm.