Numerical Analysis On Dimensional Effect Of Foundation Pit Deformation

With the continuous development of the city,the proportion of high-rise and super-high-rise buildings in urban construction has been increasing year by year.Therefore,the foundation pit project,which is both new and old,has constantly put forward higher requirements.The foundation pit project is a three-dimensional space system,but it is still used in the design and construction of many projects.The two-dimensional plane method is still used for calculation.This can not fully reflect the spatial effect of the foundation pit,so the excavation of the foundation pit is performed from a three-dimensional perspective.In this paper,a three-dimensional model of foundation pit excavation is established by the finite element calculation software ABAQUS.The spatial effects of the foundation pit are systematically analyzed from two different working conditions: different aspect ratios and with or without foundation pit precipitation.During the excavation of the subdivision,the pit excavation displacement,the retaining wall displacement,and the distribution of the bottom excavation in the excavation are summarized.The excavation size of the excavation and the effect of the pit excavation on the pit angle and the retaining wall are analyzed.Displacement and the effect of bottom uplifts are analyzed and indicated by:(1)The excavation of the foundation pit has a strong spatial effect.The minimum point of the deformation of the foundation pit after the excavation of the subdivision and after the excavation is at the pit corner,and the maximum deformation point displaces the center of the pit.(2)The displacement of the foundation pit retaining structure to the vertical direction in the pit has obvious spatial effect.The closer the space effect is to the corner of the foundation pit,the more the space effect in the middle of the pit is the weakest.(3)The geometrical size of the foundation pit has a significant influence on the deformation of the foundation pit,and the effect of the spatial effect gradually decreases when the aspect ratio increases.There is a critical length-to-width ratio.When the aspect ratio is greater than the critical aspect ratio,the deformation results of the foundation pit approach a stable value.(4)The foundation pit dewatering does not change the deformation mode of the foundation pit,but it has played an increasing role in the displacement of the pit,the displacement of the retaining wall,and the bulging of the bottom of the pit,and its partial increase even reaches over 100%.Not to be ignored.