Research On Seismic Performance Ot Fully Prefabricated Subway Station Structure Based On Mortise And Groove Grouting Joint

During the construction of urban rail transit projects in China,prefabricated subway station structure is a new kind of structure,and it is also one of the important directions for the development of subway station structure in China in the future.Prefabricated subway station structure based on tongue-and-groove grouting joint is the first work of prefabricated subway station structure in our country,which successfully solves many technical problems in the construction of underground rail transit stations in high latitude and severe cold areas in our country.However,at present,the seismic research of subway station structures mainly focuses on traditional cast-in-situ concrete structures,and there are few related researches on the seismic response laws and seismic performance of prefabricated subway station structures.Therefore,taking a fully prefabricated subway station structure of Changchun metro line 2 as an engineering example,this paper uses numerical methods to study the elastic-plastic seismic response and seismic performance of the structure.The specific research contents of this paper are as follows:(1)The seismic response laws of fully prefabricated subway station structures under dif'ferent buried depths are analyzed.By changing the depth of the station structure,the seismic performance of the station structure under different depth conditions is analyzed.This paper discusses the change rule of the interlayer displacement(angle)of the structure with the increase of the buried depth,and analyzes the influence of the joint located near the interface of soil layer on the seismic performance of the structure.(2)The influences of stiffness of assembled components,central column stiffness and joint stiffness on the seismic performance of fully prefabricated subway station structures are analyzed.By changing the assembled components stiffness,center column stiffness and interface element stiffness parameters at the joint,the seismic response law and the change of seismic performance of the station are discussed.(3)Based on the cracking bending moment of joints,the limit value of elastic interlayer displacement and cracking sequence of joints of fully prefabricated subway station structures under earthquake are analyzedThree methods for determining the elastic interlayer displacement angle limit of prefabricated subway station structures are given.Based on the second method,the elastic interlayer displacement angle limit of prefabricated subway station structures with buried depths of 5m and 3m are calculated,and the cracking sequence of joints under strong earthquakes is given.(4)Based on the ultimate bending moment of the joint,the limit value of elastic-plastic interlayer displacement angle of the fully prefabricated subway station structure and the failure sequence of the joint under earthquake are analyzed.Three methods for determining the elastic-plastic interlayer displacement angle limit of prefabricated subway station structures are given.Based on the second method,the elastic-plastic interlayer displacement angle limit of prefabricated subway station structures with buried depths of 5m and 3m are calculated,and the failure sequence of joints under strong earthquakes is given.Based on the above seismic calculation results,it can be concluded that compared with cast-in-situ subway station structure,the fully prefabricated subway station structure based on tenon-and-groove joint has good seismic performance.