【摘要】 采用OpenSees软件建立了典型矮塔斜拉桥结构三维有限元计算模型,并通过拉丁超立方体抽样方法考虑了结构构件中钢筋和混凝土强度的随机性,建立了地震动-桥梁样本集,分别针对纵桥向和横桥向两个方向,同时考虑竖向地震动分量的贡献,对有限元模型进行了增量动力分析,分别提取了矮塔斜拉桥的主塔及边墩不利截面的钢筋和混凝土的应变、主梁弯矩、斜拉索轴力以及支座的相对位移及其他受力构件的反应结果,结合相应的损伤指标,对矮塔斜拉桥结构进行了地震易损性分析,选择合理的分布函数及其参数进行易损性曲线拟合,为同类桥梁抗震设计及地震风险评估提供参考。更多还原

【Abstract】 Based on software of OpenSees,three-dimensional finite element model of typical Lower-tower Cable Stayed Bridge is established,and the randomness of concrete strength as well as steel strength is taken into account by Latin hypercube sampling method.As a result,bridge structure-ground motion samples are produced.Then Incremental Dynamic Analysis is employed in transversal and longitudinal direction concerning the participation of vertical ground motion.Finally,steel strain of main towers and side piers as well as concrete strain,stress of cables,moment of main beams of the bridge are presented as seismic response of structural components.Then,earthquake fragility analysis is carried out coupled with corresponding damage index.Vulnerability curve fitting are made by choosing a reasonable distribution function and its parameters.The study provides a reference for seismic design and seismic risk assessment of the similar bridge.更多还原