大跨简支钢桁梁人行桥人致振动测试与减振控制研究  

Research on Pedestrian-Induced Vibration Test and Damping Control of Long-Span Simple-Supported Steel Truss Girder Pedestrian Bridge

作　　者：焦晋峰 王金龙[2] 闫晓彦 路国运 陈鹏程[2] JIAO Jinfeng;WANG Jinlong;YAN Xiaoyan;LU Guoyun;CHEN Pengcheng(Department of Architecture,Lyuliang University,Lyuliang 033001,China;College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]吕梁学院建筑系,山西吕梁033001 [2]太原理工大学土木工程学院,太原030024

出　　处：《太原理工大学学报》2023年第6期1083-1092,共10页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金资助项目(52278198);山西省自然科技研究基金资助项目(202203021211184);山西省基础研究计划资助项目(202103021223105)。

摘　　要：【目的】为研究大跨简支钢桁梁人行桥在人致激励下的动力响应及调谐质量阻尼器(TMD)的减振效果。【方法】以山西省123 m跨简支钢桁梁人行桥——玄月桥为研究对象,针对该人行桥进行了现场人致振动测试和数值模拟,研究了行人在不同激励频率、行走人数、激励方式下对该结构振动的影响规律;探讨了单频调谐质量阻尼器(STMD)和多频调谐质量阻尼器(MTMD)在中心频率及调频偏差下的减振效果,提出了考虑调频偏差下结构减振优化设计建议。【结果】结果表明:低阶模态对结构振动起控制作用,行人激励频率接近结构一阶竖向基频时会产生共振,其最大加速度峰值为0.13 m/s^(2);行人跑动、跳跃激励对该人行桥振动舒适度影响较大,产生的加速度峰值分别为行走激励的194%、166%;低质量比(μ≤1.0)下STMD减振频带较窄,提高STMD总质量比μ可提高减振效果并改善其减振频带窄的问题,该人行桥STMD总质量比从0.6%提升至3.0%后,可将调频偏差β允许范围从0扩大至±15%;同一总质量比及调频偏差下,MTMD的减振效果和鲁棒性优于STMD,且随子单元数量的增大而提高。【Purposes】This work has been done in order to study the dynamic response of longspan simply-supported steel truss pedestrian bridge under human-induced excitation and the damping effect of tuned mass damper(TMD).【Methods】The research object is a 123 m span simply supported steel truss girder pedestrian bridge——Xuanyue Bridge in Shanxi Province,and on site human-induced vibration tests and numerical simulation have been carried out.The influences of different excitation frequencies,number of pedestrians,and excitation mode on the vibration of the structure are studied.The damping effects of single frequency tuned mass damper(STMD)and multiple frequency tuned mass damper(MTMD)under the central frequency and frequency deviation are discussed.【Findings】And the optimized design proposal of structural damping considering frequency deviation is proposed.The results show that the low order mode plays a role in controlling the structural vibration.When the pedestrian excitation frequency is close to the first order vertical fundamental frequency of the structure,resonance occurs,and the peak acceleration is 0.13 m/s^(2);The running and jumping excitations of pedestrians have a great influence on the vibration comfort of the footbridge,and the peak accelerations are 194%and 166%of the walking excitations,respectively;The STMD damping frequency band is narrower at low total mass ratio(μ≤1.0),improving the total mass ratio of STMDμcan improve the damping effect and simultaneously improve the problem of its band narrowing,after the total mass ratio of pedestrian bridge STMD is increased from 0.6%to 3.0%,the allowed range of fre-quency modulation deviationβcan be expanded from 0 to±15%;At the same mass ratio and frequency modulation deviation,the damping effect and robustness of MTMD are better than those of STMD,and increase with the number of sub units.

关 键 词：大跨径人行桥 人致振动测试 减振控制 调谐质量阻尼器 

分 类 号：U448.11[建筑科学—桥梁与隧道工程]