城市桥梁粘滞阻尼器防地震碰撞分析与参数设计

研究了粘滞阻尼器防止城市梁桥地震碰撞反应的效果并提出了其参数设计方法。分析了线性粘滞阻尼器与非线性粘滞阻尼器阻尼系数的等效关系。运用随机振动理论与随机等效线性化理论建立了邻联间安装粘滞阻尼器后最大相对位移及墩顶最大位移的计算方法。以控制邻联最大相对位移小于实际间隙为目标,提出了防碰撞粘滞阻尼器参数设计方法。对1座4跨隔震连续梁桥进行了仿真分析,结果表明:粘滞阻尼器能有效抑制邻联的碰撞反应且不会显著增大桥墩的延性需求。在相同阻尼系数的情况下,粘滞阻尼器的速度指数越小,其防碰撞效果越好。利用人工波进行的时程分析结果验证了参数设计方法的可行性。

Seismic pounding prevention analysis and parametric design of urban bridges using viscous damper

The performance of using viscous damper to prevent the urban bridges' pounding response is studied,and the parametric designing method of viscous damper is also proposed.The equivalent damping coefficient between linear and nonlinear viscous damper is investigated.The peak relative displacement between adjacent segments and the peak pier drift are obtained based on random vibration theory and stochastic equivalent linearization method.Parametric designing method for viscous damper is proposed for the objective of making the peak relative displacement between adjacent segments be small than actual gap size.A four-span seismic isolated continuous bridge is selected as an analytical model.Numerical analysis results show that viscous damper can prevent pounding response effectively without increasing ductility demand in the piers.Assuming the same damping coefficient,the viscous damper possessing smaller velocity index will get much better controlling performance.The feasibility of parametric designing method is verified by the results of time history analysis using artificial ground motion.