涡激振动是在低风速下很容易出现的一种风致振动现象,一维钝体涡激振动具有自激、自限特性.拍振则是涡激振动一种典型形式,为钝体固有频率和涡脱频率共同作用结果.拍振理论研究目前为止仍未有满意结果;主要通过数值计算方法和风洞试验进行研究,数值计算难度很大难以实现;风洞试验研究较直观,但不能解释其作用机制.基于Scanlan非线性模型,采用KBM法(渐近法)推导一维钝体竖向涡激振动拍振响应一次近似解,探讨通过拍振时程响应曲线识别气动参数、涡激力方法.最后,以一大跨度桥梁主梁节段模型风洞试验为例,识别气动参数及其非线性涡激力.%Vortex-Induced Vibration (VIV) is one kind of wind-induced vibration phenomenon which is easily occured on relatively low wind speed. VIV of 1-d bluff body has a few characteristics such as self-excitation,self-limitation. Beat is one representative oscillation type of VIV as a result of influence of natural frequency and vortex frequency. Beat is the representative phenomenon of coupling between flow and bluff body. Presently, there is still lack of satisfaction theory to describe beat. So the main available methods to research beat ate numerical study and wind tunnel test. However, numerical study can hardly be successful because of tremendous calculation work. Then, wind tunnel test can get VIV straightly although it can not interpret the VIV mechanism. The vertical beat response of 1-d bluff body can be expressed by Scanlan's nonlinear empirical model Furthermore,the way is discussed to identify aerodynamic parameters and vortex-induced force on beat state. Lastly,the aerodynamic parameters and nonlinear vortex-shedding force are identified by taking a long-span bridge girder section model wind tunnel test as an example.
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