摘要
在通过测量振动参数的变化来检测结构裂纹的方法中,曲率模态法是较为有效的一种。曲率模态通常由中心差分法求取位移模态的2阶导数来获得,但由于模态的测量比较困难,分辨率和精度较低,所以差分法计算误差较大。针对该情况,引入插值和加窗傅里叶变换算法来计算曲率模态,并通过带裂纹悬臂梁的测量实验进行验证。同中心差分法进行对比可知:提出的算法能大幅提升计算的精度,准确地判断裂纹的所在位置。
Vibration based crack detection methods extract the crack location information from the change of structural vibration modal properties, such as the curvature mode shape. A combined algo- rithm based on numerical interpolation and windowed Fourier transform was proposed to calculate the curvature mode shape, and an experiment was conducted to verify the algorithm. Comparison with conventional central difference approximation shows that the proposed algorithm is feasible to improve the precision of curvature mode shape calculation and then localize the crack accurately.
出处
《重庆理工大学学报（自然科学）》
CAS
2013年第9期35-37,52,共4页
Journal of Chongqing University of Technology：Natural Science
关键词
加窗傅里叶变换
裂纹检测
曲率模态
windowed Fourier transform
crack detection
curvature mode shape
