Adhesive and its aging can have influence on the Piezoelectric (PZT) elements in structural health monitoring (SHM) systems. However, the current research pays little attention to the effect of adhesives in SHM systems, and the mechanism of adhesive aging on monitoring signals is still unclear. In the present study, the relationship between types of adhesives, adhesive thickness, accelerated aging, and monitoring signal was analyzed in detail. The study was carried out with three kinds of epoxy resin AB adhesive (AW106, E-30CL, and E-120HP) and bonding thicknesses (0.01, 0.05, and 0.12 mm), and the elevated temperature was 100 °C for 45 days. The signal-based monitoring method was used to extract the characteristic parameters. The experimental results indicated that the standard shear strength and thickness of the adhesive may have a combined effect on the monitoring signal. Increasing the thickness may enhance the shear strength between PZT and the matrix. For the effectiveness of monitoring the signal propagation, however, increase in thickness may have a negative influence. Moreover, the elevated temperature will bring the signal amplitude to a peak in the first period of aging, and the highest point appears in 10 to 15 days. Nevertheless, with the increase of aging time, the adhesive will finally be degraded, resulting in the decrease of the signal amplitude. The experimental results may provide useful information for practical monitoring in the SHM field.

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胶粘剂及其老化对结构健康监测系统中压电传感器性能的影响

胶粘剂及其老化会影响结构健康监测（SHM）系统中的压电（PZT）元素。然而，当前的研究很少关注SHM系统中粘合剂的作用，并且粘合剂老化对监测信号的机理仍不清楚。在本研究中，详细分析了粘合剂类型，粘合剂厚度，加速老化和监测信号之间的关系。使用三种环氧树脂AB粘合剂（AW106，E-30CL和E-120HP）和粘合厚度（0.01、0.05和0.12 mm）进行了研究，并在100°C的高温下放置了45天。基于信号的监测方法用于提取特征参数。实验结果表明，胶粘剂的标准剪切强度和厚度可能会对监测信号产生综合影响。增加厚度可以增强PZT和基体之间的剪切强度。但是，为了有效监视信号传播，厚度的增加可能会产生负面影响。此外，温度升高将使信号幅度在老化的第一阶段达到峰值，最高点出现在10到15天之内。然而，随着老化时间的增加，胶粘剂最终将被降解，从而导致信号幅度下降。实验结果可能为SHM领域的实际监测提供有用的信息。但是，为了有效监视信号传播，厚度的增加可能会产生负面影响。此外，温度升高将使信号幅度在老化的第一阶段达到峰值，最高点出现在10到15天之内。然而，随着老化时间的增加，胶粘剂最终将被降解，从而导致信号幅度下降。实验结果可能为SHM领域的实际监测提供有用的信息。但是，为了有效监视信号传播，厚度的增加可能会产生负面影响。此外，温度升高将使信号幅度在老化的第一阶段达到峰值，最高点出现在10到15天之内。然而，随着老化时间的增加，胶粘剂最终将被降解，从而导致信号幅度下降。实验结果可能为SHM领域的实际监测提供有用的信息。粘合剂最终将降解，从而导致信号幅度降低。实验结果可能为SHM领域的实际监测提供有用的信息。粘合剂最终将降解，从而导致信号幅度降低。实验结果可能为SHM领域的实际监测提供有用的信息。