大跨度人行斜拉桥TMD减振分析

摘要:

为避免人行桥发生共振,以新金牛(岛型)公园C、D地块人行斜拉桥为例,通过数值仿真和脉动试验得到了人行斜拉桥的一阶自振频率。进一步地,选取人行激励荷载,确定舒适度评价标准。最后,数值分析了原桥的振动响应,并根据原桥动力分析结果设计了调谐质量阻尼器(TMD)减振方案。研究结果表明：本桥端跨的一阶竖弯频率为2.73 Hz,跨中频率为1.51 Hz；安装TMD后,端跨和跨中的加速度峰值符合舒适度标准,TMD减振效果最大可达到60%。

Abstract:

In order to avoid resonance of the pedestrian bridge, taking the pedestrian cable-stayed bridge in plots C and D of the Xinjinniu (island-type) park as an example, the first-order natural frequency of the pedestrian cable-stayed bridge was obtained through numerical simulation and pulsation tests. Further, the pedestrian excitation load was selected, and the comfort evaluation standard was determined. Finally, the vibration response of the original bridge was numerically analyzed, and a tuned mass damper (TMD) vibration reduction design was proposed based on the results of the original bridge"s dynamic analysis. The research results show that the first-order vertical bending frequency of the end span of the bridge is 2.73 Hz, and the mid-span frequency is 1.51 Hz. After installing the TMD, the acceleration peaks of the end span and the middle span meet the comfort standard, and the maximum vibration reduction effect of the TMD can reach 60%.