文章简要阐述了地铁抗震分析常用计算方法的优缺点及适用性,并结合青岛地铁4号线人民会堂站实际情况建立有限元模型,计算分析地震荷载作用下车站动力特性,通过对比结构各点内力及位移,结果表明:(1)反应位移法、反应加速度法计算地震响应结果普遍比时程分析法大,且车站刚度越大,偏差越大;(2)鉴于E3状态下结构弹塑性本构误差较大,对于截面变化不大、地层较为简单的车站弹塑性层间位移可采用弹性层间位移乘以延性系数;(3)惯性力法计算普遍比反应位移法小,但当车站惯性力起主导作用(即车站刚度相对于土体很大)时,惯性力法与反应位移法计算相差不大;(4)青岛车站基本位于花岗岩中,结构动力响应90%是由剪切力引起,不同于昆明、常州、郑州等土体抗震分析结果;(5)地铁结构层间位移角随车站埋深增大而增加,随矢跨比、围岩弹模、二次衬砌厚度增加而减少,但其中二次衬砌厚度对层间位移角影响最小,车站埋深影响最大.%The advantages, disadvantages and applicability of common calculation methods for aseismic analysis of metro tunnels are briefly described. A finite-element model is established based on the People's Hall Station of Qing-dao metro line 4, and the dynamic characteristics of a metro station under a seismic load is calculated and analyzed. A comparison of the internal force and displacement at each point of the structure shows:1) the seismic response results calculated by the response displacement method and response acceleration method are generally larger than those calculated by the time-history method, and the greater the station stiffness, the larger the difference; 2) in light of a large elastic-plastic constitutive error of the structure under an E3 state, the elastic-plastic interlayer displacement can be obtained by multiplying the elastic interlayer displacement and ductility coefficient for the station in the simple stratum;3) the results calculated by the inertia force method are generally larger than those calculated by the response displacement method, while the difference is small if the station inertia force plays a leading role (i.e., the station stiffness is very great with respect to the soil mass);4) the Qingdao station is basically located in granite, with 90%of the structure dynamic response caused by shear force, so the aseismic analysis results of the soil mass are different from those of Kunming, Changzhou and Zhengzhou; and 5) the interlayer displacement angle of the metro structure increases with an increase of the station overburden but decreases with an increase of the risespan ratio, elastic modulus of the rock mass and thickness of the secondary lining, while the thickness of the secondary lining has little effect on the angle of the interlayer displacement and the station overburden has greatest effect on the angle of the interlayer displacement.
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