摘要
提出改进的动能密度指标损伤识别法,基于加速度测试数据,直接在时域内进行损伤识别。首先从理论上分析了动能密度指标,介绍了基于该指标建立的损伤识别方法;接着指出了该方法存在的问题,并详细分析了原因;然后针对这些问题,采用基线修正技术及小波包变换方法对该方法进行改进;最后将改进后的动能密度指标识别法用于一连续梁数值模型和一钢框架动力试验的损伤识别,结果表明该方法能够有效识别损伤位置,大概反映损伤程度;并且无需完备的模态信息,能克服激励的影响,具有良好噪声鲁棒性,适用于多种结构的损伤识别。因此,可以预见该方法具有较大的工程实用价值。
A new time-domain structural damage identification strategy, the improved kinetic energy density based method, was developed using the measured acceleration signals. The kinetic energy density index was deduced theoretically and the commonly used identification method based on this index was introduced. Several disadvantages of the method were pointed out and the corresponding reasons were analysed. According to these, an improvement utilizing the wavelet packet transform and the datum line correction technique was proposed. The improved kinetic energy density based strategy was then applied to structural damage detection of a numerical model of two-spans continuous beam as well as an experimental model of three-storeys steel frame. The results verify the effectiveness and performance of the new strategy, show its immunity of interference between exciting force and noise and demonstrate its adaptability to various structures in the case of incomplete modal information.
出处
《振动与冲击》
EI
CSCD
北大核心
2009年第8期35-41,共7页
Journal of Vibration and Shock
基金
国家自然科学基金(50778077
50608036)
关键词
损伤识别
动能密度
小波包变换
基线修正
动力试验
damage identification
kinetic energy density
wavelet packet transform
datum line correction
structural dynamic experiment
