拉索摩擦摆支座在曲线梁桥中的抗震分析

Seismic response analysis of cable-sliding friction pendulum bearings in curved girder bridges

针对曲线梁桥弯扭耦合严重、地震危害明显等特点,提出一种更适于曲线梁桥的减隔震支座-拉索摩擦摆支座。以一座实际城市曲线梁桥为背景,建立曲线梁桥在4种支座下的三维模型,真实模拟了支座处于双向滑动极限工作状态的性能,重点讨论拉索摩擦摆支座在曲线梁桥上的减隔震效果;引入减震率概念,对比了4种模型在5种参数下差异。结果表明:此支座能够有效降低曲线梁桥中墩、边墩内力,减小弯扭耦合作用,将墩、梁相对位移限制在设计范围内,且具有较好的能力需求比。通过调整拉索的自由程或摩擦摆的摩擦系数可以得到最优减隔震效果。

According to the characteristics of curved girder bridge,i.e.bending and torsion coupling,and serious seismic hazard,we put forward a more suitable bearing for urban curved girder bridge-cable-sliding friction pendulum bearing(CSFPB).Based on a real bridge,a 3D model of a curved girder bridge was established under the four models and a real simulation of limit performance of the bearing in the state of bi-directional sliding,focused on CSFPB isolation effect on the curve girder bridge and introduced the concept of damping rate and compared the four kinds of models in five parameters.The results show that this bearing can effectively reduce the internal force of the middle pier and side piers and the coupling effect,limit the relative displacement between the pier and the beam in the design range,and has a good demand ability.Through the adjustment of the initial free movement and friction coefficient we can obtain the optimal isolation effect.