Study On Seismic Response And Simplified Seismic Analysis Method For Subway Station Considering The Influences Of Adjacent Buildings

Urban rail transit has become the core solution of large-capacity rapid public transport system in big cities or megacities and urban rail transportation infrastructure construction has become a major demand for national development.Recently,With the further acceleration of urban rail transportation infrastructure construction and the increasing density of urban rail traffic networks,a lot of urban rail transit subway stations are constructed near clusters of ground buildings.It brings a new challenge for seismic response analysis and seismic design of urban rail underground structures.Different to single subway stations,the subway stations adjacented to ground buildings are not only affected by site deformation,but the inertia forces of ground buildings producted in seismic event also deliver to subway stations.The studies on seismic responses of subway stations considering the influences of adjacent ground buildings have important scientific significance and application prospect.Therefore,via the dynamic equilibrium analysis on the whole model,substructure analysis on the subway station adjacented to ground building,parametric analysis,numerical simulation analysis on engineering example,and other methods,this paper focuses two key issues of seismic response characteristics and seismic design method of the subway station adjacented to ground buildings.This research aims to solve the deficiencies of current research on subway station-soil-ground building dynamic interaction,and provides guidances and methods for seismic design of subway stations in dense urban environments.The main work and research achievements are summarized as follows:(1)A theoretical analysis on the dynamic interaction of subway station-soil-ground building is carried out based on integrated and substructure model,and the mechanism of seismic response of the subway station adjacented to ground building is revealed from the viewpoint of kinematic and inertia interactions.The seismic responses of the subway stations adjacented to ground buildings can be distinguished as the kinematic interaction induced by the field movement and the inertial interaction induced by the vibration of ground building,according to generation mechanism.(2)The effects of different factors(such as dynamic characteristics of ground buildings,structure form of subway stations,relative position of underground and ground structures,seismic inputs,site conditions and so on)on the kinematic and inertial interactions of the subway station adjacented to ground building are parametric discussed,and the seismic responses characteristics of subway stations considering the influences of adjacent buildings are systematically investigated.(3)Taking the seismic response mechanism as breakthrough point,the three-dimensional spatial characteristics of seismic responses of the subway stations adjacented to ground buildings is explored based on a three-dimensional numerical simulation study.The transverse spatial characteristic(side walls are more affected than columns,and the side wall of hall layer near the ground building is most affected)and longitudinal spatial characteristic(the longitudinal influence range of ground building on seismic response of subway station including “core area” and two “transition areas”.The length of “transition area” is 7 times the spacing of columns)of seismic response of the subway station adjacented to ground buildings are determined,through the analyses on internal force and deformation at different positions of subway station.(4)The failure mechanism and failure mode of the subway stations adjacented to ground buildings under strong earthquake are explored based on the nonlinear static-dynamic coupling analysis.By comparing with the single subway station,the influence of adjacent ground buildings on the nonlinear development law of subway station is obtained and the aseismic weak component(the side wall of the station hall layer near the ground building)of the subway station adjacented to ground buildings is determined.(5)According to the mechanisms and characteristics of seismic responses of the subway stations adjacented to ground buildings,two simplified seismic analysis methods of subway station cross-section considering the influences of adjacent buildings are derived from the integrated model and substructure model,respectively.The new methods have the advantages of “higher calculation accuracy,safer structure design,less time consumption and faster analysis process” in seismic design of the subway stations adjacented to ground buildings.(6)“The three-dimensional response acceleration method” and “two plus twodimensional equivalent analysis method” of the subway stations adjacented to ground buildings are acquired via the dimension promotion of pseudo-static analysis methods of subway station cross-section.Two three-dimensional pseudo-static seismic analysis methods of the subway stations adjacented to ground buildings not only can provide safety design,accuracy calculation results,but also reduce the difficulty of threedimensional seismic analysis.(7)A topical analysis method based on truncated model is proposed according to the three-dimensional spatial characteristics of seismic response of the subway station adjacented to ground buildings.The topical analysis methods can greatly reduce the calculation difficulty and improve the efficiency of three-dimensional seismic design.,while ensuring the calculation accuracy.