Research Of Lateral Deformation Of Deep Excavation In Soft Soil Area

The deformation of retaining structure of foundation pit that caused by excavation is various and complex influence factors. In the soft soil area, because the soft soil has many characteristics such as high compressibility, low shear strength and the high water content, the construction of foundation pit engineering technical is more difficult, the deformation control is more difficult. Based on Delisle, Foshan area building foundation pit engineering as the research object, through the measured data of the project, the lateral deformation law and location of the maximum lateral deformation is analyzed, and through the finite element software MIDAS GTS numerical simulation analysis was carried out on the foundation pit,and research on several influence factors of Deformation summary. Finally based on these factors, using the potential energy in value theorem is deduced from a simple analytical formula of foundation pit lateral deformation, the main results were as follows:(1) Based on the data of Foshan's Delisle building foundation pit engineering project monitoring, analysis of the foundation pit excavation, the excavation of RuanTu District domain of deformation rate sped up and the location of the lateral deformation of the largest moving down as the foundation pit excavation and causes; Found the second position of the lateral deformation of the general is located in the upper portion of the maximum lateral deformation position; Deformation of soft soil deep foundation pit has obvious time effect,accounted for about 20% of the total deformation.(2) Using the finite element software MIDAS GTS simulates the process of foundation pit excavation and compare with experimental data and the simulated results and measured data of each construction stage alignment is higher, also verify the feasibility of finite element simulation.(3) Based on the finite element model, this paper discusses the crown beam deformation,deformation of deep soft soil location, the last line of support and overload on the influence of the deformation of foundation pit lateral deformation and the maximum lateral position.Through the reasonable control of these factors effectively control deformation of foundation pit, and determine the position of the largest lateral deformation.(4) Using earth pressure that consider the deformation of retaining structure, the use of potential energy in value theorem puts forward a simple forecast the lateral deformation of the retaining structure analytic expression, and compare with experimental data.