大跨人行天桥基频研究  

Study on fundamental frequency of large span footbridge

作　　者：高婷婷 石宇[1] 

机构地区：[1]长安大学建筑工程学院,陕西西安710061

出　　处：《地震工程与工程振动》2014年第1期199-203,共5页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(51108033);中央高校基本科研业务费专项资金资助(2013G3286001)

摘　　要：对西宁市拟建大跨人行天桥进行有限元模拟分析,得到结构的基频和最不利荷载工况下竖向最大挠度,指出其挠度满足规范要求,基频却不满足。理论推导人行天桥基频限值的计算公式,公式表明:人行天桥基频限值与其结构形式、行人脚步频率、桥身自重、桥上活荷载以及桥梁跨度有关,其他条件一定时,基频限值随天桥跨度增大而减小。根据中国行人步频实际情况计算不同跨度天桥的基频限值,理论验证西宁市拟建的天桥满足生活中人们对天桥的舒适度要求。： Using finite element method to analyze the large span cross-shaped footbridge in Xining, the fundamental frequency and maximum vertical deflection of the structure under most critical load condition were obtained. Further more, it is pointed out that the deflection could meet the requirements of specification while the fundamental fre- quency could not meet. The fundamental frequency limit value calculation formula is deduced and the calculation results show that the fundamental frequency limit values are affected by structure form, pedestrian step frequency, self-weight, live load and bridge span. If other conditions are fixed, the fundamental frequency declines with the increase of the footbridge span. Calculation of the fundamental frequency for footbridges with different spans com- bined with the step frequency of Chinese pedestrians can vertify that the footbridge in Xining can meet the public＇ s requirements for comfort.

关 键 词：基频 大跨 人行天桥 限值 计算公式 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]