Design And Numerical Simulation Analysis Of Support Structure Of A Pit Project In Handan

Taking a deep foundation pit engineering in Handan as the research background,the design and numerical simulation of the deep foundation pit software and Midas/GTS NX finite element software are applied respectively.Then,by comparing it with the field monitoring data,the reliability of the support scheme and the rationality of the numerical model are verified.The main research contents of this paper are as follows:In this paper,a deep foundation pit engineering is taken as the research background.The design and calculation of the supporting structure are carried out by using the rational deep foundation pit software,and the excavation process of the foundation pit is numerically simulated by Midas/GTS NX finite element software.(1)The supporting structure is designed by Lizheng deep foundation pit software,and the overall stability,anti overturning and anti uplift of the foundation pit are checked,and the verification results meet the requirements of the specification.;(2)The Midas/GTS NX limited software was used to simulate the excavation process of the 1-1 area on the east side of the foundation pit,and the horizontal and vertical displacement of the foundation pit,the surrounding surface settlement and the deformation of the retaining pile were analyzed.The simulation results show that the maximum horizontal displacement of the foundation pit is 15.16 mm,the maximum settlement is 12.53 mm,the maximum positive moment of the retaining pile is 241.58kN·m,the maximum negative bending moment is 480.62kN·m,and the maximum shear force is 278.99 kN.,the maximum negative shear force is 251.83kN;(3)Comparing the calculation results,simulation results and on-site monitoring results,it can be seen that the design of the supporting structure meets the safety requirements of the specification and the finite element model is relatively accurate;(4)The impact analysis of the supporting structure was carried out,mainly considering the influence of the diameter of the supporting pile and the spacing of the supporting pile.In this paper,the influence of the support pile diameter and the support pile spacing was studied.By comparison,it was found that appropriately increasing the pile diameter(reducing the pile spacing)can effectively control the horizontal displacement of the supporting structure and ensure the stability of the foundation pit.Considering comprehensively,it was more reasonable to choose the diameter of supporting piles 0.80 m and the spacing of supporting piles 1.60 m in this project.In this paper,the support structure design and numerical simulation analysis of the foundation pit are carried out before the construction of the project,and the results provide help for the construction of the project.After the completion of the foundation pit construction,the design value,simulation value and monitoring value are compared,the deformation law and the cause of the difference are analyzed,and some experience is accumulated,which can provide reference for the design and construction of similar foundation pit projects in Handan area in the future.