应力板带桥动力特性与人致振动响应实测  

Field Measurement of Dynamic Properties and Human-inducedVibration of a Stress-ribbon Footbridge

作　　者：姚彦娜 程思远[1] 姚彦强 杜慧慧[1] YAO Yanna;CHENG Siyuan;YAO Yanqiang;DU Huihui(School of Civil Engineering,Hebei Polytechnic Institute,Shijiazhuang 050091,China;Railway Construction Section of South Taiyuan,Daqin Railway Co.,Ltd.,Taiyuan 030012,China)

机构地区：[1]河北工程技术学院土木工程学院,石家庄050091 [2]大秦铁路股份有限公司太原南工务段,太原030012

出　　处：《噪声与振动控制》2023年第5期260-267,共8页Noise and Vibration Control

摘　　要：开展应力板带桥动力特性与人致振动响应的现场实测工作。首先,基于环境激励和冲击法,开展该桥动力特性测试;其次,基于随机子空间法和峰值拾取法,获得应力板带桥的前三阶自振频率、振型与阻尼比;最后,基于该桥动力特性实测结果,开展单人和队列同步行走以及随机行走测试,获得桥的人致振动响应,并对其振动舒适性进行评价。研究表明:(1)应力板带桥动力系统具有典型的低频、小阻尼比(<0.002)和密集模态特点;(2)人群同步行走时的结构响应并非单人响应的线性放大;与桥面人数相比,结构振动响应对行走步频更为敏感;(3)进行振动舒适度评价时应充分考虑结构使用功能和所处环境。The dynamic properties and human-induced responses of stress-ribbon footbridge were measured.Firstly,the modal test of the bridge was conducted using ambient vibration testing and impact methods.Secondly,the natural frequencies,mode shapes and the damping ratios of the first three orders of the bridge were identified based on stochastic subspace identification(SSI)method and peak-pick method.Finally,the bridge responses under pedestrian loading were measured considering synchronization of the structure under single-person walking and group motion as well as random walking cases.The vibration comfort of the bridge was evaluated based on the test data.Results show that:(1)The bridge is characterized with low natural frequencies,low damping(<0.002)and dense modes;(2)the bridge response under crowd synchronous motion is not a linear superposition of the single-person induced ones.Compared with pedestrian number,it is more sensitive to step frequency.(3)The function and service environment should be fully considered in structure vibration comfort evaluation.

关 键 词：振动与波 应力板带桥 动力特性 行走激励 动力响应 现场实测 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]