地铁地下车站结构的地震反应特性研究

摘要

通过Davidenkov动力本构模型模拟土体、动塑性损伤模型模拟混凝土的动力特性，建立土-地铁地下车站相互作用的二维有限元分析模型，研究地铁车站结构的地震损伤演化规律和能量反应特性，结果表明：地震动特性对地铁车站结构的能量反应特征有明显影响，地铁车站结构的阻尼耗能和滞回耗能逐步增加；通过滞回耗能密度衡量各构件滞回能量耗散的集中效应，发现中柱的滞回能量最为集中，说明地震动作用下中柱的动力反应最大；通过对地铁车站结构的地震损伤过程研究，发现局部和整体损伤指数时程变化规律一致，在变形累积效应下表现出递增特性．%The dynamic Davidenkov model is used to model dynamic characteristics of soils, and plastic-damage model is used to model dynamic characteristics of station structure concrete. So that, considering the influence of soil-station structure interaction for 2D finite element analysis, the dynamic interaction of soil-station structure is modeled. The damage characteristics and energy response of station structure under seismic motion is analyzed. The result shows that damping energy and hysteretic energy are monotone increasing under ground motion, and the seismic characteristic has significant effect on the energy response of subway station structure. Furthermore, concentration effect of hysteretic energy of subway station structure is measured by hysteretie energy density. It is found that the hysteretic energy is the most centralized in the column, so the dynamic response of the columns is the maximum. Furthermore, the nonlinear damage evolution law of station structure is analyzed. The law of local and global damage index is consistent essentially, and the damage index is increased by the effect of accumulative deformation.