The estimation of the damping coefficient may help to improve the damage detection in composite materials. The purpose of this study was to develop the simulated Lamb wave propagation method for nondestructive monitoring of matrix cracking in laminated composites via the accurate estimation of their damping coefficient. Cross-ply composite specimens with different crack densities were fabricated and tested by the Lamb wave propagation technique. The phase velocity of the Lamb wave and the damping coefficient of the specimens were measured. The finite element models were developed at micro-scale (representative volume elements) and macro-scale (laminated specimens) levels to simulate the Lamb wave propagation in composite specimens. An optimization process was performed through the model updating procedure to achieve finite element models that were in good agreement with experiments. The phase velocity and damping coefficient, obtained from the updated FE models for two crack densities other than those used in the model updating procedure, were successfully examined by experimental results. It was also revealed that the damping coefficient and the rate of increase in the damping coefficient in terms of the crack density were higher for the composite laminates with a higher number of 90° layers. The damping of the fiber–matrix interphase and crack regions were considered in the model and shown as a significant contribution to the overall damping of the composite specimens. The proposed simulated Lamb wave propagation method can be used as a virtual lab for in-situ monitoring of laminated composites with different material properties, stacking sequences, and crack densities.

阻尼系数的估计可以帮助改善复合材料中的损伤检测。这项研究的目的是通过精确估计阻尼系数来开发模拟Lamb波传播方法，以无损监测层压复合材料中的基体开裂。用兰姆波传播技术制作并测试了具有不同裂纹密度的交叉复合材料试样。测量了兰姆波的相速度和样品的阻尼系数。在微观（代表体积元素）和宏观（层压样品）水平上开发了有限元模型，以模拟兰姆波在复合样品中的传播。通过模型更新程序执行了优化过程，以实现与实验良好吻合的有限元模型。通过更新实验结果，成功地从更新的有限元模型中获得了两个裂纹密度以外的相速度和阻尼系数，该密度不同于模型更新过程中使用的密度。还显示出，对于裂纹数而言，阻尼系数和阻尼系数的增加率对于具有更高的90°层数的复合层压板而言较高。在模型中考虑了纤维-基体相间和裂纹区域的阻尼，并显示出对复合材料样本整体阻尼的显着贡献。