LRB 隔震桥梁双向耦合非线性地震反应分析摘 要 为了讨论铅芯橡胶支座（LRB）隔震桥梁在双向水平地震激励下的非线性地震反应，首先建立了模拟水平正交两向作用力条件下 LRB 支座非线动力行为的双向耦合弹塑性恢复力模型，这一双向耦合弹塑性模型中的单向力和变形关系的骨架曲线为双线性。在此基础上，提出了一种双向水平地震激励下多跨连续 LRB 隔震桥梁的非线性地震反应分析模型以及求解方法，并对考虑和忽略 LRB 支座恢复力的双向耦合作用时隔震桥梁的非线性地震反应进行了算例比较分析，讨论表明这种双向耦合作用对隔震桥梁的地震反应有重要影响，假如忽略这些相互作用的影响，支座位移的峰值将被低估，这对隔震桥梁设计是不利的。关键词 隔震桥梁 铅芯橡胶支座 双向耦合弹塑性模型 非线性地震反应Bi-directional Coupled Nonlinear Seismic Responses of Isolated Bridges with LRBAbstract In order to investigate the nonlinear seismic responses of isolated bridges with lead rubber bearings (LRB) under bi-directional horizontal earthquake excitation, the bi-directional coupled elastic-plastic model of force-deformation behavior of LRB under two horizontal orthogonal directional excitation is established, and the unidirectional force-deformation behavior skeleton curve of this bi-directional coupled elastic-plastic model is considered as bilinear. Based on the bi-directional coupled elastic-plastic model of LRB, an analytical model of nonlinear seismic responses of continuous multi-span isolated bridges with LRB and its solving method are presented. Finally, the comparison of the calculation results of nonlinear earthquake responses obtained by considering and ignoring the bi-directional coupled interaction of bearing restoring force is made for the one example of the isolated bridges with LRB. It is shown that the bi-directional coupled interaction of the restoring forces of LRB has considerable effects on the seismic responses of the isolated bridge. If thes...
