十字交叉换乘地铁车站地震响应分析

Seismic Response Analysis of Cross Transfer Subway Station

目的 研究十字交叉换乘地铁站在抗震分析中地震动荷载对结构动力响应的影响,为十字交叉车站的抗震设计和分析提供参考。方法 以十字交叉换乘地铁站为研究对象,借助MIDAS-GTS建立三维有限元分析模型,采用动力时程方法分析水平与竖向地震动荷载下车站结构的地震响应规律,并将单向与双向耦合地震动荷载下的结构响应进行比较。结果 双向地震动荷载下,结构响应规律与单向地震动相似,但结构水平位移增幅为1.44%,竖向位移增幅为1.21%;层间位移角比水平地震动增加了12%,比竖向地震动增加了1 876%;结构加速度响应在水平向增加了4.1%,在竖向减少了2.8%。结论 在双向地震动荷载下,结构的地震响应增大,产生的动力效应更大,对结构损伤更大;顶板的加速度峰值最大,最易受损;由于ρ-Δ效应,结构水平向地震响应增大,竖向地震响应减小。

In order to study the influence of the vertical ground seismic load on the dynamic response of the structure in the seismic analysis of the cross transfer subway station,it can provide some reference for the seismic analysis of the cross-transfer subway station.Taking the structure of an underground three-layer cross transfer subway station as the research object,a three-dimensional finite element analysis model is established by using the finite element software MIDAS-GTS.Considering the nonlinearity of soil,the dynamic time history analysis method is used to analyze the seismic response law of the cross transfer station structure under horizontal and vertical ground motions,and compared the response of the structure under unidirectional and bidirectional coupling ground motions.Under the action of bidirectional seismic loads,the dynamic response of the structure is similar to that of unidirectional seismic loads,but the average increase in horizontal displacement of the structure is 1.44%,and the average increase in vertical displacement is 1.21%;The interlayer displacement angle increased by 12%compared to horizontal seismic motion and 1876%compared to vertical seismic motion;The structural acceleration response increases by 4.1%horizontally and decreases by 2.8%vertically.Under the coupling effect of bidirectional seismic loads,the seismic response of the structure significantly increases,resulting in greater dynamic effects and ultimately causing greater damage to the structure;The peak acceleration of the top plate is the largest and most susceptible to damage;Due to the effect,the horizontal seismic response of the structure increases,while the vertical seismic response decreases.