蜂窝夹层复合材料悬臂梁损伤检测的试验研究

EXPERIMENTAL INVESTIGATION ON DEBONDING DAMAGE DETECTION OF HONEYCOMB SANDWICH CANTILEVER BEAM

进行了用互相关函数幅值向量(crosscorrelation function amplitude vector,CorV)和连续小波变换(continuous wavelet transform,CWT)联合检测损伤的试验研究。采用蜂窝夹层梁试件,在保证试件其它结构参数一致的情况下,分别人为制造了不同位置的脱粘损伤。首先测试随机激励下完好结构和损伤结构的振动加速度响应,计算归一化的互相关函数幅值向量,再选取双正交小波函数分别对其进行连续小波变换,根据损伤前后小波系数的变化来检测结构的损伤状态,以小波系数差的模的最大的两个极大值作为损伤指标来进行损伤定位。该方法无需对结构建模,仅需获取结构损伤前后的时域振动响应信号。试验研究结果验证了用该文提出的联合检测方法检测蜂窝夹层复合材料结构损伤的有效性。

Experimental investigations are performed on the damage detection for honeycomb sandwich composite beams by using a combined damage detection method. The debonding damages of the honeycomb sandwich beams are artificially induced in different positions. The combined detection method is incorporated with the correlation function amplitude vector （CorV） analysis and the continuous wavelet transform （CWT）. Only the time domain vibration responses of the intact and damaged structures are required in the damage detection procedure. In the detection, the beam is excited with steady random excitation. CorV of the beam is calculated by using the measured vibration responses at all the measured points. Then these CorVs of intact and damaged beam are analyzed by biorthogonal continuous wavelet transform. The results demonstrate that the debonding damage of the structure can be identified by comparing wavelet coefficients of the intact and damaged structures. And the damage region can be located through the two maximum modulus of the difference of the coefficients obtained from intact and damaged structures.