Deformation Monitoring And Numerical Simulation Of A Deep Foundation Pit Shaft In West Railway Station Of Changchun Subway Line2

With the development of economy and the growth of population density,urban transportation construction is very important for the meaning of a city.Good transportation planning and layout can reasonably guide flow.When the local space has been developed by people,underground space would have began to draw people's attention,and more and more underground engineering began planning and carried out.The underground works of a-subway,as a large volume of urban traffic,urban development and transportation planning has the ability to make a miracle.Changchun subway construction is proceeding in an orderly manner,the subway involved in the construction of deep foundation pit construction scale and the depth of excavation are the field of geotechnical engineering has brought a lot of theoretical and technical problems.Commonly used methods of deep foundation pit excavation are finite element numerical simulation methods and on-site construction monitoring methods.The finite element method can pre-drill the excavation process to determine whether the foundation pit design and construction method is safe and reliable.However,the finite element method is limited by the selection of constitutive relation,the quality of grid division and the setting of boundary conditions.It is often different from the actual situation of the project,and the site construction monitoringIt is from the foundation pit structure of the internal force deformation,the displacement of the soil around the pit and other aspects of monitoring the entire foundation pit,so as to avoid a major accident pit,while the measured data and numerical simulation can be compared to verify the numerical analysis Simulation method of reliability,feedback construction.This paper takes the deep foundation pit engineering of a subway shaft in Changchun as the engineering background.Based on the theory of deep foundation pit and combined with engineering practice,the finite element simulation method and the site actual monitoring method are used to study the deformation law of surrounding soil caused by excavation of deep foundation pit.The main work is as follows:1.By reviewing the literature,summarize the mechanism of deformation of thefoundation pit;2.Introduce the contents of the foundation pit monitoring,elaborate the actual monitoring program formulation method,the statistical analysis of the measured data,summed up some of the deformation of the foundation pit deformation;3.Through the simulation of the excavation process of the foundation pit,the reliability of the numerical simulation is verified by the measured data,and four foundation pit models with different depth are excavated respectively.Then,the excavation deformation and excavation depth Relationship.