Field Monitoring And Numerical Simulation Study On Deformation Of Supporting Structure Of Deep Foundation Pit Excavation

With the continuous development of city construction,the importance of underground space development is growing,the subsequent construction of deep foundation pit engineering becomes a hot topic,and the stress and deformation analysis of the supporting structure is one of the important research topic.Based on the combination of theoretical analysis,field actual monitoring and Midas-GTS numerical simulation,this paper takes the Zhengzhou comprehensive transportation hub underground traffic engineering(east square)project as the background,through the field measured data,the deformation law of supporting structure under different working conditions of the project are studied,the main contents include:(1)This paper describes the present situation of the development of deep foundation pit engineering at home and abroad,and the research status of field monitoring and numerical simulation of deep foundation pit.(2)This paper introduces the structure and main characteristics of the pile-anchor supporting system for the deep foundation pit engineering,and discusses its mechanism of action from the interaction between the pile-soil interaction,the interaction between the bolt and the soil and the force characteristics of the whole structure of the three angles.(3)This paper introduces the formulation of the field monitoring scheme of the project,monitors the horizontal displacement of the pile structure,the horizontal displacement of the pile top and the force of the anchor during the excavation of the foundation pit,and then analyzes and obtains the change law.(4)The numerical simulation of the finite element software Midas-GTS is used to analyze the results of the finite element simulation and the field monitoring results.It can be seen from the anlysis that because the complex factors of the construction site can not be reflected in the model one by one,so the simulated datas and measured datas have certain deviation,but the trend of the development of the two is basically the same,so it can verify the stability of deep foundation pit and the correctness of the model numerical simulation,but also for the future deep foundation pit engineering monitoring measurement provides a certain experience.(5)On the basis of verifying the previous model,the influence of different anchor prestress,different anchor angle and different ground overload on the deformation of the supporting structure are analyzed by numerical simulation.The deformation results of foundation pit supporting structure under different parameters are obtained.