考虑行人舒适度的空间缆索悬索桥车致振动控制  

Control of Vehicle-induced Vibration of Suspension Bridge with Spatial Cable Considering Pedestrian Comfort

作　　者：唐茂林[1] 王鹏[1,2] 李翠娟 TANG Mao-lin;WANG Peng;LI Cui-juan(School of Civil Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China;Changjiang Institute of Survey,Planning,Design and Research,Wuhan Hubei 430010,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]长江勘测规划设计研究有限责任公司,湖北武汉430010

出　　处：《公路交通科技》2020年第1期58-65,共8页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(51478391)

摘　　要：带有人行道的市政轨道交通桥梁在地铁作用下会有较大的动力响应,进而影响桥上行人走行舒适度。为了研究地铁荷载激励下桥上行人走行的舒适度,依托某市政空间缆索体系悬索桥,在有限元分析软件ANSYS中建立结构三维模型,考虑轨道不平顺的影响,在列车荷载激励下进行瞬态非线性时程分析。结果发现:当轨道不平顺的谐振频率接近桥梁一阶竖弯模态频率时,桥梁结构出现了共振效应,动力响应显著增大,峰值加速度达到1.122 m/s^2,桥上行人走行舒适度处于"不舒适"等级。为了有效抑制结构振动,改善桥上行人走行舒适度,采用Den Hartog最佳参数确定方法得到调谐质量阻尼器主要参数值,分别研究了单调谐频率质量阻尼器(STMD)和多调谐频率质量阻尼器(MTMD)对结构振动的控制效果,得到STMD系统控制下结构最大加速度为0.731 m/s^2,有效降低了34.8%;MTMD系统控制下结构最大加速度为0.681 m/s^2,有效降低了39.3%,添加阻尼器都使桥上行人舒适度从"不舒适"进入"中度舒适",但是MTMD系统具有更好的抑振效率。随着结构使用过程中收缩徐变、老化等情况的出现,结构自振频率也会发生改变,最后对比结构自身频率改变时STMD与MTMD的抑振效果,得出MTMD具有更好的鲁棒性,更适合长久服役,并且在一定范围内子TMD个数越多,鲁棒性越好。The urban transit railway bridge with sidewalk,excited by subway loading,usually has high-amplitude dynamic response,which significantly affects the pedestrian comfort.In order to study the walking comfort on the bridge under the subway load excitation,taking an urban suspension bridge with spatial cables for example,the structural 3D model is established in FEA software ANSYS.Considering the track irregularity,the transient nonlinear time-history analysis under subway loading is conducted.The result shows that(1)when the resonance frequency of track irregularity approaches the first-order vertical bending mode frequency of the bridge,there comes resonance and the dynamic response increases significantly,the peak acceleration reaches 1.122 m/s^2,and the walking comfort of the pedestrians is in the"uncomfortable"level.In order to effectively suppress the structural vibration and improve the pedestrian comfort,the main parameter values of tuned mass damper(TMD)are obtained by using Den Hartog’s determination of optimum parameters,and the control effects of STMD and MTMD on structural vibration are studied respectively.The maximum acceleration of the structure controlled by STMD system and MTMD system is 0.731 m/s^2 and 0.681 m/s^2 separately,which effectively reduces up to 34.8% and 39.3% respectively.The comfort level is improved by TMD from"uncomfortable"to"moderate",and MTMD can suppress vibration more efficient than STMD.With the occurrence of shrinkage,creep and aging of the structure during service,its natural frequency will also change.At last,the vibration suppression effects of STMD and MTMD when changing of the natural frequency of the structure are compared.The result shows that MTMD owns better robustness than STMD,it is more suitable for long-term service,and the more TMDs in a certain range,the better the robustness.

关 键 词：桥梁工程 振动控制 有限元分析 舒适度 鲁棒性 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]