Damage Detection in Composite Plates by Using an Enhanced Time Reversal Method
Damage Detection in Composite Plates by Using an Enhanced Time Reversal Method
复制标题
DOI：
10.1061/(asce)0893-1321(2007)20:3(141
复制
发表时间：
2007-07
影响因子：
2.4
通讯作者：
H. Sohn;Hyun Woo Park;K. Law;C. Farrar
中科院分区：
文献类型：
--
作者：
H. Sohn;Hyun Woo Park;K. Law;C. Farrar
提出了一种不依赖于任何过去基线信号的损伤检测技术，通过使用增强的时间反演方法来评估复合材料板中的损伤。现代声学的时间反演概念已被改编为导波传播，以提高复合材料结构中的局部缺陷的检测能力。特别是，基于小波的信号处理技术已被开发，以提高薄复合材料层压板中的兰姆波的时间可逆性。在增强的时间反演方法中，如果在另一点处测量的响应信号在时域中被反演之后被重新发射到原始激励点，则可以重建激励点处的输入信号。这种时间可逆性是基于弹性波的线性互易性，并且当非线性由沿直接波路径的缺陷沿着引起时，它被违反。检查重建信号与已知初始输入信号的偏差允许瞬时识别损伤，而不需要用于比较的基线信号。通过对含脱层的准各向同性层合板的实验研究，验证了该方法的有效性。
A damage detection technique, which does not rely on any past baseline signals, is proposed to assess damage in composite plates by using an enhanced time reversal method. A time reversal concept of modern acoustics has been adapted to guided-wave propagation to improve the detectability of local defects in composite structures. In particular, wavelet-based signal processing techniques have been developed to enhance the time reversibility of Lamb waves in thin composite laminates. In the enhanced time reversal method, an input signal at an excitation point can be reconstructed if a response signal measured at another point is reemitted to the original excitation point after being reversed in a time domain. This time reversibility is based on linear reciprocity of elastic waves, and it is violated when nonlinearity is caused by a defect along a direct wave path. Examining the deviation of the reconstructed signal from the known initial input signal allows instantaneous identification of damage without requiring the baseline signal for comparison. The validity of the proposed method has been exemplified through experimental studies on a quasi-isotropic laminate with delamination.