框架式地铁车站结构大地震近场地震反应特性的三维精细化非线性分析

基于 ABAQUS 软件的 32CPU 显式有限元并行计算集群平台，建立了深软地基土–框架式地铁地下车站结构体系三维精细化非线性地震反应分析的有限元模型，数值模拟了汶川大地震清平波、卧龙波和 100 a 超越概率 3% 的南京人工地震波作用下深软地基上三层三跨框架式地铁地下车站结构地震反应特性的差异。结果表明：大地震近场强地震动将对深软地基上地下车站结构造成严重损伤，甚至发生塑性破坏或坍塌，柱、楼板、侧墙的结合部位是抗震的不利位置，中柱为抗震最薄弱构件，输入近场地震动的峰值加速度和频谱特性对地下车站结构的地震反应均有很大影响；地下车站结构的地震反应具有明显的空间效应，且在大地震近场强地震动作用下地下结构会产生单向累积的永久位移；清平波、卧龙波作用下地下车站结构的地震反应远大于 100 a 超越概率 3% 的南京人工地震波作用下的地震反应；结构浅埋部分的地震损伤比深埋部分更大。

3D refined nonlinear analysis of seismic response characteristics of frame metro station under near-field strong ground motion of large earthquake

Based on the explicit finite method of ABAQUS software and the 32CPU parallel computing cluster platform,a three-dimensional refined finite element model for deep soft soil-frame metro station structure is established to study its nonlinear seismic responses to Qingping and Wolong ground motions recorded during Wenchuang Earthquake and Nanjing artificial waves with the exceedance probability of 3% within 100 years.The results show that the underground frame metro station structure in deep soft site may be seriously damaged under near-field strong ground motion,and even plastic failure or collapse may appear.Moreover,the combining sites of pillars,floor slabs and side walls are in unfavorable positions in seismic resistance,while the pillars are the weakest components.In addition,the peak acceleration and the spectrum characteristics of the input near-field ground motions also have great influences on the earthquake response of the underground structure.The seismic response of the subway station structure has a noticeable three-dimensional effect.Furthermore,the structure will generate permanent displacements to be accumulated to one side under the near-field ground motion of large earthquake.The structural responses under Qingping and Wolong ground motions are obviously larger than those under Nanjing artificial waves.Besides,the seismic damage of shallowly buried parts is more than that of the deep ones.