Seismic Performance Analysis Of Shallow Buried And Underground Excavated Metro Tunnel And Existing Bridge Piles

With the development of society,the level of medical care has gradually improved,urban population has become more dense,and traffic pressure has become heavier.People began to study various transportation systems,The subway has become an important tra nsportation system among people's studied transportation systems.The subway construction technology in our country is becoming more and more mature,Metros are common in first-tier cities.Since subways are mainly used to solve people's transportation problems,if they are built in densely populated areas,the construction environment will become very complicated in places with a lot of people,For example,the buildings around subway stations,buried underground pipelines and optical cables will become important factors affecting construction safety,The construction cost of subways is very high.In recent years,large and small earthquakes have occurred in our country.Once the earthquake damages the subways,it will not only affect people's travel,but also bring significant economic losses,People are of great significance.Due to the uncertainty of when the earthquake will occur and its size,this article starts with the construction of the tunnel.Based on the actual engineering background,this paper analyzes the actual monitoring data and uses MIDAS GTS NX software for modeling,Simulate the tunnel excavation process,perform static simulation,process the simulation results and compare with the measured data to verify the model's rationality,then according to the actual construction plan,the model's middle partition wall is removed,and secondary support is provided,and then a dynamic simulation is performed to study the vibration response of the tunnel under different conditions by changing parameters.The main work of this article is as follows:(1)Collect information about the tunnel excavation process,analyze the actual monitoring data,analyze the changes in the tunnel and its impact on the surrounding environment,and establish a static model based on the actual construction plan and survey report,and run the static model,cloud map results,compared with the actual monitoring results,it mainly compares ground settlement,bridge pile foundation settlement and bridge pile foundation displacement,and verifies each other with headroom convergence and bridge pile foundation displacement to verify the rationality and rationality of the tunnel static model.(2)Based on the actual working conditions,a dynamic model is established based on the static model,and different parameters are simulated.The tunnel is shaken by changing the direction of the different shocks under the same wave to find the weak point of the tunnel in the earthquake,that is,the first failure in the earthquake.(3)Change the stiffness of the lining by changing the thickness of the tunnel lining and the grade of the concrete used for the lining.According to the displacement and stress cloud diagrams and time-history curves of the tunnel and bridge pile foundation,obser ve the influence of the change in the stiffness of the lining on the tunnel itself and the existing bridge pile foundation during the earthquake.The influence law of lining stiffness on tunnel and pile foundation of existing bridge is summarized.Provide reasonable suggestions for the design and construction of tunnels in Shenyang and similar geological conditions in the future(4)According to the characteristics of the tunnel damage and the seismic analysis of the tunnel,some reasonable construction s uggestions are proposed to improve the seismic resistance of the tunnel.