大跨悬索桥梁端位移响应减振性能评估和设计

Assessment and Design of Mitigation of Longitude Displacement of Suspension Bridges

大跨悬索桥的梁端纵向位移响应影响伸缩缝的疲劳寿命。为了评估梁端纵向位移响应减振,以矮寨大桥为工程背景建立了全桥空间有限元模型。研究了矮寨大桥的自振特性,分析了模态的“纵飘”特性与纵向位移响应之间的关系。在此基础之上,研究了粘滞阻尼器和中央扣对悬索桥梁端纵向位移响应的减振。结果表明,粘滞阻尼器和中央扣都能在一定程度上控制梁端位移响应,同时两者的减振性能受自身参数影响较大,最后提出了大跨悬索桥梁端纵向位移响应减振措施的优化设计思路。

The longitudinal displacement response of the girder affects the fatigue life of the expansion joint of the long-span suspension bridge.In this study,the Aizhai Bridge was chosen to investigate and assess the mitigation of longitude displacement response.The finite element model was applied to perform the eigenvalue analysis,and the dynamic characteristic of the Aizhai Bridge was discussed.Moreover,the mitigation of the viscous fluid damper and the central buckle on the longitude displacement response was investigated.The numerical results show that both the viscous damper and the central buckle can control the displacement response of the girder to a certain extent,the performance of them is greatly affected by their own parameters.Finally,based on the theoretical analysis,the optimal design consideration of the mitigation of longitudinal displacement response was proposed.