连续小波变换在梁结构损伤诊断中的应用研究

为了检测出梁中的裂缝或因刚度降低引起的损伤,对有损伤简支梁的振型曲线进行连续小波变换．从小波系数出现模极大值有效地识别损伤的存在以及裂缝位置和刚度下降段的位置。基本振型是用小波变换识别裂缝的最佳振型．用损伤位置处振幅较大的振型曲线来识别最清楚,对有噪声影响的振型曲线同样可以用本文方法进行识别。通过分析和计算获得满意结果．在梁结构损伤诊断中具有较高的应用价值。

Application of Continuous Wavelet Transform to Detection of Beam Damage

To detect beam damage,the vibration mode shapes of a simple supported beam with cracks or damage caused by a decline of stiffness are analyzed using continuous wavelet transform.The existence and location of the damage are identified by the maximum of wavelet coefficients.It is showed that the first vibration mode shape is the best one for damage detection.This method is also efficient in the presence of noise.The validity of the proposed method is investigated by both analysis and simulation.The method may be useful in damage detection of beam structures.