一种基于自由振动法的改进颤振导数识别算法  

An improved flutter derivative identification algorithm based on free vibration method

作　　者：卢宝洁 祝兵[1] 饶家锐 李志家 崔圣爱[1] Lu Baojie;Zhu Bing;Rao Jiarui;Li Zhijia;Cui Sheng'ai(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,成都610031

出　　处：《东南大学学报（自然科学版）》2024年第6期1481-1488,共8页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金面上资助项目(52178167,52278221)。

摘　　要：为提高提取主梁弯扭耦合时程响应特征参数和颤振导数的可靠性,在全局最小二乘法的基础上提出了一种改进的分级遍历迭代算法.首先,基于Theodorsen理论得到理想平板模型的颤振导数和特征矩阵;然后,在求解特征参数的基础上,利用状态空间法建立理想位移时程数据并进行参数识别,选用随机激励干扰信号和倍频干扰信号测验分级遍历算法的鲁棒性;最后,采用主梁节段模型测振试验检测该算法的实际应用性.结果表明:分级遍历迭代算法对初值要求较低,在接近颤振临界风速的敏感区域,特征参数识别误差小于0.2%;对于噪声强度5%以内的随机激励干扰和10%以内的倍频信号干扰,所提算法能够有效提取信号特征参数,重构位移时程曲线;对于与桁架转角相关的主颤振导数,所提算法与MUL S法的识别误差小于1.4%.An improved hierarchical traversal iterative algorithm is proposed based on the global least squares method to improve the reliability of extracting characteristic parameters and flutter derivatives in the bending-torsion coupling time-domain response of the main beam.The flutter derivative and the eigenmatrix of the ideal plane model are derived based on the Theodorsen theory.The characteristic parameters are solved to establish the ideal displacement time-history data using the state-space method and realize parameter identification.The robustness of the hierarchical traversal iterative algorithm is tested using random incentive disturbance signals and harmonic disturbance signals.The practicality of this algorithm is verified by main beam segment model vibration testing.The results indicate that the hierarchical traversal iterative algorithm has low initial value requirements.The characteristic parameter identification errors are less than 0.2%in the sensitive zone approaching the flutter critical wind speed.For random excitation interference with the noise intensities within 5%and harmonic signal disturbances within 10%,the proposed algorithm can effectively extract signal characteristic parameters and reconstruct displacement time-domain curves.For the primary flutter related to truss rotation angles,the identification errors between the proposed algorithm and the modified unifying least-squares(MULS)method are less than 1.4%.

关 键 词：颤振导数 最小二乘法 参数识别 自由振动法 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]