Study On Influence Of Deep Foundation Pit Excavation And Internal Support On Deformation Of Adjacent Pipelines In Soft Soil Area

The study on the deformation of the foundation pit and its influence on adjacent pipelines is of great significance for guiding the construction of the project,curbing and reducing the occurrence of engineering accicdents.Based on a deep foundation pit in Shanghai,this paper combines numerical simulation and on-site monitoring to develop the design of foundation pit support scheme,comparison of schemes,deformation of foundation pit enclosure and influence of adjacent pipelines.research work.The main contents are as follows:Determination of the optimal support scheme.According to the relevant specifications and engineering geological conditions in Shanghai,three kinds of support schemes are designed for the west side of A-1.area of a deep foundation pit in Shanghai area,and the bending moment and shear force of the underground continuous wall during excavation are analyzed.Displacement and deformation of surface settlement.Comprehensive safety and economic factors are better than the optimal support plan.The amount of deformation of the pipeline varies with the distance between the pipeline and the foundation pit.According to the optimal enclosure scheme and on-site engineering geological conditions,the model was established using MIDAS-GTS.In order to analyze the influence of the distance between th,e pipeline and the foundation pit on the pipeline,on the basis of the existing pipeline,add a heel pipeline at the same embedding depth every 3m,and calculate and analyze the adjacent pipeline in the excavation process of the scheme.The deformation of the enclosure provides a reference for the on-site construction of the foundation pit project.The monitoring plan design and on-site measurement work were completed.The deep horizontal displacement,surface settlement,deformation trend and regularity of adjacent pipelines of underground continuous wall are analyzed,and the rationality of monitoring scheme and foundation pit support scheme is verified.The comparison between monitoring data and numerical simulation data shows that the numerical simulation model and calculation parameters are reasonable,and the numerical simulation shows that the optimal support scheme is reasonable,which can provide reference for the design of foundation pit at the same depth in soft soil area.