摘要
在强震作用下柱式钢筋混凝土桥墩会进入塑性状态,采用考虑有刚度退化的武田三线型模型(弯矩-曲率关系),对一典型的双柱式桥墩进行了弹塑性有限元抗震分析,通过引入等效塑性铰长度的概念将其简化为两自由度结构模型,采用考虑有刚度退化的武田三线型模型(力-位移关系)进行计算。研究结果表明,墩顶位移结果及滞回曲线形状均吻合较好,为柱式桥墩的弹塑性抗震计算提供了一种简单可靠的计算途径。
When the RC column bridge pier subject to intense earthquake excitation,the pier will enter into the state of plasticity.In this paper,based on a tri-linear hysteretic modal(moment~curvature relationship) taking into consideration of the depression of the secant stiffness,a representative double-column bridge pier is analyzed under seismic excitations by the elastic-plastic FEM.By introducting the concept of ′equivalent length of plastic hinge',the FEM modal was simplified as 2DOF modal.Considering the tri-linear hysteretic modal(force~displacement relationship) the 2DOF was analyzed under seismic excitations.The study shows that the displacement of the pier at the top fits the hysteretic curve well.So the method this paper put forward provides a simple and credible approach to calculate the elastic-plastic seismic response of column bridge pier.
引文
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