Abstract Marine structures are exposed to various destructive factors during their serviceability. Therefore, timely damage detection and repair of these structures at early stages can increase their service life and prevent economic and human losses as much as possible. In this study, a method is presented to identify the location of multiple damages in the piles of a dolphin pier. In the first step of the proposed method, based on a combination of the Wavelet Packet Energy Curvature Difference (WPECD) and the Richardson extrapolation, a damage index is introduced to accurately find the damage zone/damaged piles in the dolphin wharf. The energy curvature difference of the wavelet packet was obtained based on the vibrating signals of the structure. Using an image processing technique, in the second step of the method, the locations of damage were extracted via the WPECD method. The efficiency and capability of the proposed method was confirmed by numerical and experimental results. The exact geometry of the damages in the experimental model was initially scanned by a three-dimensional scanning device. Then, the scanned images were processed and imported into the numerical model as an input file. Finally, the results showed that the proposed method could discover multiple structural damages with acceptable accuracy.

中文翻译：

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小波包能量曲率差与Richardson外推相结合的结构损伤检测

摘要 海洋结构物在其使用过程中会受到各​​种破坏性因素的影响。因此，对这些结构进行早期及时的损伤检测和修复，可以提高其使用寿命，尽可能避免经济和人员损失。在这项研究中，提出了一种方法来识别海豚码头桩中多处损坏的位置。在所提出方法的第一步中，基于小波包能量曲率差（WPECD）和理查森外推法的组合，引入损伤指数以准确地找到海豚码头中的损伤区/损伤桩。小波包的能量曲率差是基于结构的振动信号获得的。使用图像处理技术，在该方法的第二步中，通过 WPECD 方法提取损坏的位置。数值和实验结果证实了所提出方法的效率和能力。实验模型中损伤的精确几何形状最初是由一个三维扫描设备扫描的。然后，对扫描图像进行处理并将其作为输入文件导入到数值模型中。最后，结果表明，所提出的方法可以以可接受的精度发现多个结构损伤。扫描图像被处理并作为输入文件输入到数值模型中。最后，结果表明，所提出的方法可以以可接受的精度发现多个结构损伤。扫描图像被处理并作为输入文件输入到数值模型中。最后，结果表明，所提出的方法可以以可接受的精度发现多个结构损伤。