力-状态映射法在桥梁断面涡振研究中的应用

Application of the force-state mapping method in studying the vortex-induced vibration of bridge decks

基于模拟生成的两个具有不同非线性特性的桥梁断面涡激振动系统对传统经验非线性模型做了进一步研究,研究表明经验非线性模型虽然很好模拟了原始系统自限幅振动特性,却无法模拟系统非线性气动力的形式。提出了一种基于力-状态映射的涡振分析方法,该方法既可以模拟系统自限幅振动特性,也可以模拟系统气动力的形式。并且,可以通过均方差(MSE)和重要性指数对总体气动力中的各项贡献进行评价,为气动力形式的确定提供依据。

A detailed study on the conventional nonlinear semi-empirical model was conducted through two different vortex-in-duced vibration （VIV）systems of bridge decks.Results indicate that the nonlinear semi-empirical model can reproduce the lim-it cycle oscillation （LCO）of the original systems,but it cannot reproduce the forms of nonlinear aerodynamic forces.A new approach,which is based on the force-state mapping method,was proposed for simulating the VIV of original systems.This approach performs well in simulating both the LCO and the aerodynamic forces of the original systems.Moreover,the mean square error （MSE）and the significant factor can be used as a criterion in determining the form of nonlinearities in aerodynamic forces.