Study On Dynamic Interaction Between Stratum Deformation And Surface Building Of Tunnel Construction

With the development of the ages and the acceleration of urbanization process,the enthusiasm of building subways in many cities are crazily rise.With high population and intensive building in urban areas,subway construction will inevitably affect the surrounding surface buildings.Unreasonable construction measures will even cause the buildings to reach the limit of normal use or the ultimate state of load capacity,thuslosing their function.Therefore,it is important to study the interaction mechanism of tunnel construction through buildings and analyze the process of tunnel-stratum-building interaction,which is important for protecting the surface buildings.In this paper,by stochastic medium,DEM analysis,finite element analysis and other means and combined with engineering cases,to analysis of tunnel-stratum-building interaction relationship under the influence of tunnel construction.The main work and research results are as follows:(1)Based on the theory of stochastic medium,the MATLAB programming program is compiled to calculate the deformation law of the surface subsidence under the influence of the single line tunnel and the double line tunnel.The influence factors such as tunnel depth,excavation section size and construction process are analyzed.The PFC2D particle flow analysis software was used to establish the model of particle flow in the presence of surface structures,and the dynamic relationship between tunnels and strata-buildings under the influence of tunnel excavation was analyzed from the angle of macroscopic and microscopic interaction.It is pointed out that the effect of tunnel excavation is a dynamic process that gradually spreads from the periphery of the tunnel to the surface.The existence of buildings makes the interaction more complex,need to use a common model for analysis.(2)The finite element analysis software ABAQUS was used to establish the two-dimensional model of tunnel-strata-building interaction.The interaction between the building and the ground was analyzed by means of contact connection.and the interaction was coMPared with the model without of surface buildings.Considering the different crossing relationship,it is pointed out that considering the contact relationship,the separation between the building and the strata under the condition of shallow tunnel depth will occur,and the contact model is used to analyze the interaction.(3)The finite element analysis software ABAQUS was used to establish the three-dimensional analysis model of tunnel-strata-building interaction,and the interaction between the three conditions was analyzed.Mainly including geological parameters,tunnel crossing angle and the different excavation sequence of two-lane tunnel.The study shows that the dynamic relationship between the tunnel and the stratum-the building is reflected in the dimension of time and space.Therefore,it is necessary to consider the spatial position relation,excavation step and geological conditions of the building and tunnel in construction.(4)Based on the engineering case and finite element analyze method,this paper analyzes the displacement and deformation of the buildings in the construction of Xiamen Airport Road through intensive buildings,mainly analyzes the dynamic deformation process of Building 34,and controls the settlement of the stratum and building protection measures.It is pointed out that tunnel construction is an extremely complicated process coMPared with finite element simulation.There are many influencing factors,which need to determine the main influencing factors and take appropriate control measures.