人致人行桥侧向振动中时滞影响的研究  

Influence of Time Delay on the Lateral Vibration of Footbridges Induced by Pedestrians

作　　者：刘隆[1] 谢伟平[1] 

机构地区：[1]武汉理工大学土木工程与建筑学院,武汉湖北430070

出　　处：《土木工程与管理学报》2013年第1期6-9,15,共5页Journal of Civil Engineering and Management

基　　金：国家自然科学基金(51178365);教育部博士点基金(200804970007);湖北省自然科学基金(2010lj0015)

摘　　要：由行人引起的伦敦千禧桥过度的侧向振动引起了工程界的广泛关注,Arup公司的工程师基于伦敦千禧桥的现场测试,给出了人群侧向力的模型,解释了千禧桥侧向振动现象。Nakamura基于Arup模型和实验,考虑了人群-桥梁相互作用中的非线性因素,提出了侧向力的Nakamura模型。为便于定性讨论,将Nakamura模型中的非线性部分替换为双曲正切函数,并考虑了人对桥梁侧向振动反馈中的反应时间,在模型中的速度反馈项中引入了时滞的影响。通过对改进的Nakamura模型的定性非线性分析,揭示了人行桥侧向振动与Nakamura模型的参数之间的联系,重点讨论了时滞对人行桥动力行为的影响,得到了适当的时滞可以抑制桥梁的侧向振动的结论,数值仿真证明了这一结论。The excessive lateral vibration of the Millennium Bridge induced by pedestrians attracts widely attention of the engineering researchers around the world. Arup engineers provide a lateral force mode of pedestrians according to the case tests on the Millennium Bridge, to explain the onset of lateral oscillation. Based on Arup model and experiments, Nakamura gives another model of the lateral force, and in the model, the nonlinear factors of the crowd-bridge interactlon is considered. In order to facilitate qualitative discussion, the nonlinear part of the Nakamura model is replaced by the hyperbolic tangent function, and a time delay is introduced in the velocity feedback to consider the response time of pedestrian on a lateral oscillation bridge. And through qualitative nonlinear analysis on the adapted Nakamura model, the relation between the lateral vibration of the pedestrian bridge and the parameters of the model is revealed, especially on the relation between the lateral vibration of the bridge and the time delay. The results show that proper time delay can inhibition the lateral vibration of the pedestrian bridge. And numerical simulation proofs this conclusion.

关 键 词：人行桥 人致振动 侧向振动 时滞 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]