Design And Numerical Simulation Of Pile Anchor Support For A Deep Foundation Pit In Handan

On the context of the deep foundation pit project in Handan,Lizheng deep foundation pit software is used to calculate and design the site,and Midas/GTS NX is applied for three-dimensional simulation on various working conditions of the foundation pit profile selected in this paper.Main research contents and results are as follows:(1)Determine the design scheme of foundation pit slope supporting,use Lizheng deep foundation pit software to calculate deformity and internal force of every construction condition,verify that stability of the deep foundation pit project meets the specification's needs,and determine the stability of the supporting structure.(2)Apply Midas/GTS NX to build the model and analyze soil deformation for excavation of foundation pit,deformation for support pile,as well as anchor cable stress condition and rules.The settling volume of foundation pit surface is less than apophysis of the foundation pit bottom,and maximum settling volume is 15.71 mm,and maximum apophysis is 17.03 mm.Maximum horizontal displacement of the support pile increases with increase of the cutting depth.The overall deformation is like “arch”.Numerical simulation results show that maximum horizontal displacement at the 9.50 m of the support pile body is 13.50 mm.(3)Compare and analyze value of simulation,monitoring value and Lizheng calculated value.Through calculation of above values,the trend for vertical settlement and horizontal displacement of the support pile is almost the same,and numerical simulation results are closer to actual monitoring results,which has verified model accuracy and feasibility of software of finite element analysis in the actual project.(4)Simulate and analyze the effect of different pile diameters,pile distance,pile length and anchor cable prestress on the support pile.Maximum horizontal displacement of the support pile reduces with the increase of pile length,pile diameter and anchor cable prestress,and increases with the increase of the pile distance.If pile diameter,pile distance,pile length and anchor cable prestress are changed,maximum bending moment of the support pile changes.However,the trend of the bending moment changes is the same,and the position for point of inflection remains unchanged.