大跨度钢结构人行天桥舒适度分析

Comfort Analysis of a Large-span Pedestrian Bridge of Steel Structure

针对人行天桥振动及造成的行走舒适性问题,以杭州市拱墅区某钢框架结构大跨度人行天桥为例,介绍了大跨度人行天桥项目的舒适度分析过程:采用有限元软件建立计算模型,通过验算结构竖向自振频率,计算人行天桥在人行激励荷载作用下的竖向振动加速度,以判定其舒适度。在竖向振动峰值加速度不满足相应规范和文献限值要求时,通过增设TMD阻尼器的方法,可有效抑制人行天桥桥面在人行荷载激励下的振动,改善其竖向振动加速度峰值。这表明采用TMD阻尼器改善人行天桥舒适度切实可行,可为同类型人行天桥项目舒适度分析提供借鉴。

The paper explains the vibration of pedestrian overpass and the walking comfort issues caused by the vibration,taking a large-span pedestrian bridge of steel frame structure in Gongshu district of Hangzhou city as an example,the comfort analysis process of large-span footbridge project is introduced:the finite element software is used to establish the calculation model,by checking the vertical natural frequency,calculating the vertical vibration acceleration of the footbridge under the action of pedestrian excitation load,determine its comfort.When the peak acceleration of vertical vibration does not meet the requirements of relevant specifications and literature limits,the method of adding TMD damper can effectively suppress the vibration of pedestrian bridge deck under the excitation of pedestrian load,reduce the peak value of its vertical vibration acceleration,the results show that it is feasible to use TMD damper to improve the comfort of pedestrian overpass.This paper can provide reference for the comfort analysis of similar pedestrian overpass projects.