动态测压与POD方法相结合对桥梁涡振的分析  

Research on Vortex-Induced Vibration of Bridge Based on POD and Dynamic Pressure Measurement

作　　者：胡传新 杨立坤[2] 周志勇[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]天津市市政工程设计研究院,天津300457

出　　处：《力学季刊》2013年第4期591-598,共8页Chinese Quarterly of Mechanics

摘　　要：实际应用中,桥梁涡振稳定性可用风洞试验的结果作为评估标准,但涡振时断面的压力空间分布特征是不清楚的.对弹性悬挂的刚体模型在涡振时及固定时(来流风速与涡振风速一致)的表面压力进行采样,分析模型在涡振时和固定时的表面各部分压力特性,结果显示,表面压力波动主要集中在下游部分.随后运用本征正交分解(POD)方法分析模型表面压力分布特征与涡振之间的关系,结果显示,所获得的本征模态中存在与涡振关联极强的‘主导模态',该模态对总升力系数波动的贡献占绝对主导地位.其余模态所含能量较少,且与涡振的关联性很小.本文的工作为涡振机理的研究提供了新的思路和方法.The vortex vibration stability of bridges could be evaluated by the wind tunnel test. However, the spatial distribution of the surface pressures on the section is unclear. The surface pressures of the flexible suspension rigid model in the static and vortex vibrating condition were both acquired with the same flow velocity. Based on analyzing the distribution of the surface pressures, the fluctuation of the surface pressure centralized at the downstream part were found. Then the relationship between the pressures and vortex vibration was obtained by the proper orthogonal decomposition （POD） method. The result shows that one of the eigen modes has a strong association with the vortex vibration. Its contribution to lift coefficient plays a dominant role in the vibration of lift coefficient. So this mode is called ＇dominant mode＇. The other modes have little energy and are hardly relevance to the vortex vibration. A new method to research the vortex vibration mechanism was provided.

关 键 词：POD 表面压力 涡振 正交分解 

分 类 号：TU311.3[建筑科学—结构工程]