基于摩擦摆球型支座的多跨曲线连续梁桥抗震性能

Seismic Performance Analysis of Multi-Span Curved Continuous Girder Bridges Based on Friction Pendulum Spherical Bearings

为了探讨多跨曲线连续梁桥的抗震性能和减隔震方法,对基于摩擦摆球型支座的多跨曲线连续梁桥构建了有限元模型,并进行了动力特性和非线性时程分析.结果表明,桥梁模型的纵向刚度弱于横向刚度,且第1阶振型对桥墩纵向地震反应贡献较大,振型参与系数为29.8%,第6阶振型对桥墩横向地震反应贡献较大,振型参与系数为20%;在E1地震作用下,设置的摩擦摆球型支座能够使桥梁保持弹性工作状态,且支座变形和伸缩缝宽度满足要求;在E2地震作用下,部分桥墩的截面最大弯矩需求大于截面的抗弯承载能力,而进一步的桥墩强度验算发现,结果均满足抗震需求.

To study the seismic performance and vibration isolation method of multi-span curved continuous girder bridge,a finite element model is established for the multi-span curved continuous girder bridge with friction pendulum spherical bearings,and the dynamic characteristics and nonlinear time analysis is carried out.Results show that the longitudinal stiffness of the bridge model is weaker than the transverse stiffness,and the first-order vibration mode contributes more to the longitudinal seismic response of the bridge pier,and the vibration mode participation coefficient is 29.8%;the sixth-order vibration mode contributes more to the transverse seismic response of the bridge pier,and the vibration mode participation coefficient is 20%;under the E1 earthquake,the friction pendulum spherical bearing can keep the bridge in elastic working condition,and the bearing deformation and expansion joint width meet the requirements,which proves the effectiveness of the selected and arranged friction pendulum spherical bearing;under the E2 earthquake,the maximum bending moment demand of the section of some piers is greater than the bending capacity of the section,but further strength tests were carried out on the piers,and they all meet the seismic demand.