基于频率响应的不同结构损伤识别方法研究_汪之松.pdfVIP

第 25 卷第 6 期 Vol.25 No.6 工 程 力 学 2008 年 6 月 June 2008 ENGINEERING MECHANICS 6 文章编号：1000-4750(2008)06-0006-08 基于频率响应的不同结构损伤识别方法研究 * 汪之松， 郭惠勇，李正良 (重庆大学土木工程学院，重庆 400045) 摘 要：为了解决结构损伤中的刚度和质量识别问题，将测量的响应位移应用于结构的损伤识别中，并提出了多 频率激励损伤识别方法和改进的单频率激励损伤识别方法。对于多频率激励情况，首先分析了结构损伤的基本理 论，然后推导了其刚度损伤指标和质量损伤指标的识别公式；对于单频率激励情况，则首先根据结构的刚度特性 和质量特性确定结构损伤的简化定位方法，在此基础上提出了其相应的迭代改进策略，以提高识别的精度。数值 仿真结果表明：对于刚度影响占主导地位的桁架结构，多频率激励法对于刚度损伤的识别效果较好，对于质量损 伤的识别效果较差；而采用改进的单频率激励识别策略，则可以更好的识别出刚度和质量的损伤，其识别结果优 于多频率识别法和简化单频率识别法。 关键词：频率响应；损伤识别；损伤指标；简谐激励；自由度缩减 中图分类号：TU311.3; O313 文献标识码：A IDENTIFICATION METHODS FOR DIFFERENT STRUCTURAL DAMAGE BASED ON FREQUENCY RESPONSE * WANG Zhi-song , GUO Hui-yong , LI Zheng-liang (School of civil Engineering, Chongqing University, Chongqing 400045, China) Abstract: In order to solve the stiffness and mass identification problems of structural damage, two damage detection approaches based on measured responses are presented, i.e. the Multiple Frequency Excitation Identification (MFEI) method and the improved Single Frequency Excitation Identification (SFEI) method. In the MFEI method, the basic theory of structural damage is first introduced, and then the formulas to calculate stiffness damage index and the mass damage index are proposed, which is based on the measured response of multiple frequency excitations. In the improved SFEI method, the simplified localization method of structural damage is first presented according to the stiffness and mass characteristics, and then an improved iterat