摘要
为研究人行悬索桥在人行荷载下的振动舒适度问题,以某景区人行悬索桥为依托,首先通过计算,确定了该人行悬索桥的敏感模态和规范荷载作用下的振动响应;然后,现场实测了该桥动力特性和人致振动响应,得到了该人行悬索桥的自振动力特性参数和多种人行荷载工况下的加速度响应。基于计算和实测结果,综合评价该人行悬索桥的舒适度,并在此基础上进行了调谐质量阻尼器(TMD)的减振分析。结果表明:有限元分析和实测加速度响应均超过了规范限值,该人行悬索桥人致振动问题突出;当人群密度较小时(<0.7人/m^(2)),振动响应随行人密度整体呈线性增长,增长速度与步频相关;人群的行走方式对振动响应的影响较为明显,多列同向行走使振动响应明显增大;TMD的振动控制效果十分明显,TMD的减振效率与TMD的质量比、安装位置等参数有关,对该人行桥而言,质量比为1.25%时,TMD的减振效率最高。
In order to study the vibration comfort of the pedestrian suspension bridge under the pedestrian load,this paper,based on the pedestrian suspension bridge in a scenic spot,first determines the sensitive mode of the pedestrian suspension bridge and the vibration response under the standard load through calculation,and then,the dynamic characteristics and the man-made vibration response of the bridge are measured in the field,and the natural vibration dynamic characteristic parameters of the pedestrian suspension bridge and the acceleration response under various pedestrian load conditions are obtained.Based on the calculated and measured results,the comfort of the pedestrian suspension bridge is comprehensively evaluated,and on this basis,the vibration reduction analysis of tuned mass damper(TMD)is carried out.The results show that the finite element analysis and the measured acceleration response obviously exceed the limit value of the specification,and the problem of man-made vibration of the pedestrian suspension bridge is prominent;when the crowd density is small(<0.7 person/m^(2)),the vibration response increases linearly with the pedestrian density,and the increasing speed is related to the gait frequency;the walking mode of the crowd has obvious influence on the vibration response,and the multi row walking in the same direction increases the vibration response obviously;the vibration control effect of TMD is very obvious.The vibration reduction efficiency of TMD is related to the mass ratio and installation position of TMD.For this pedestrian bridge,when the mass ratio is 1.25%,the vibration reduction efficiency of TMD is the highest.
作者
方建华
武芳文
谢亮
秦枭
冯彦鹏
FANG Jianhua;WU Fangwen;XIE Liang;QIN Xiao;FENG Yanpeng(Shaoxing Rail Transit Group Co.,Ltd.,Shaoxing,Zhejiang 312000,China;School of Highway,Chang an University,Xi an,Shaanxi 710064,China)
出处
《公路工程》
2022年第6期74-84,107,共12页
Highway Engineering
基金
陕西省自然科学基础研究重点项目(2022JZ-32)
中央高校基本科研业务资助项目(300102212212)。
关键词
人行悬索桥
人致振动
舒适度评价
现场实测
调谐质量阻尼器(TMD)
pedestrian suspension bridge
human induced vibration
comfort evaluation
field measurement
Tuned Mass Damper(TMD)
