Analysis On Ground Settlement Of Foundation Pit With Diaphragm Wall And Internal Bracing In Soft Soil Area

The exploitation and utilization of underground space becomes one of the key of city construction in recent years.A large number of large-scale foundation pit engineering not only bring opportunities for the research of foundation technology development,but also make challenges and difficulties for engineering technicians.A large number of engineering examples show that the impact of deep foundation pit excavation wide range,especially in relatively poor areas of geology,that has a huge impact to the surrounding structures and the environment.So the most important part of protect people's property and life safety is to control the deformation caused by deep foundation excavation.This article introduces the method for estimating the ground settlement based on the summary of former,combined with monitoring data of Delaier Building foundation pit engineering example and finite element analysis.The more close to the practice of engineering estimation method is put forward,and considering the influence of different design parameters on the ground settlement,which provides technical reference for the design of foundation pit.The main contents and conclusions of this article are:1.Summarizing deformation of foundation pit and its theory,and introduces Nie Zongquan's model,which according to Shanghai,Tianjin and other places established by the ground surface settlement induced by excavation of multiple deep foundation pit.2.Combination of soft soil deep Foundation pit project of Foshan,based on the monitoring data,detailed analysis of the survey data as well as the surrounding ground settlement of foundation pit,summarized lateral deformation of diaphragm wall and surrounding ground surface settlement in the overall excavation of foundation pit.Found that the lateral deformation of Foundation pit with excavation depth was "arch",and as the excavation,settlement increased.3.In order to better analyze deformation regulation of foundation pit.Numerical simulation of the actual project,analyzes the lateral deformation of Foundation pit diaphragm wall under overall excavation,results consistent with the observed trend.In addition,when excavation to the end,settlement with the distance from the pit "concave" glyphs,and by analyzing the results of the second chapter is devoted to improving the estimation methods.By the improved method,the calculated value of the settlement is in agreement with the simulated and measured values,and the calculated values are close to the measured values.The feasibility of the finite element simulation analysis is verified and the practicability of the method is verified4.The influence of different design parameters on the deformation of foundation pit is analyzed and compared by finite element simulation.Considering even wall stiffness and the bottom soil reinforcement,the effect of deformation of foundation pit,so as to improve the design method of deep foundation pit in soft soil area.