Abstract Composite laminates are usually made of anisotropic viscoelastic materials with layer-dependent properties. Although such structures are advantageous over the traditional single-material structure, their interfacial damage/failure is a great concern. In this paper, we present the general formulation and the corresponding solution to enhance our understanding on the guided waves in such laminates with imperfect interfaces. The formulation is based on the modified dual variable and position (DVP) method combined with a powerful and accurate root-finding algorithm. While the former overcomes the numerical instability when handling layered structures, the latter finds all the roots of the dispersion equation in a complex domain providing the full three-dimensional (3D) dispersion curves. After the proposed formulation is validated by the semi-analytical finite-element (SAFE) method for the perfect interface case, the present solution is applied to analyze the dispersion curves and mode shapes for a bilayer laminate with imperfect interface. Numerical examples demonstrate the detailed evolution mechanisms on wave features from perfect interface to complete delamination in the bilayer with imperfect interface. The results presented in this paper provide important insight to guide the in-situ monitoring of the evolution processes of the wave mode shapes and dispersion curves from perfect interface to complete delamination.

中文翻译：

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一般各向异性粘弹性复合层压双层中的波：不完美界面从完美到完全分层的影响

摘要 复合材料层压板通常由具有层相关特性的各向异性粘弹性材料制成。尽管这种结构优于传统的单一材料结构，但它们的界面损坏/失效是一个很大的问题。在本文中，我们提出了一般公式和相应的解决方案，以增强我们对这种具有不完美界面的层压板中导波的理解。该公式基于改进的双变量和位置 (DVP) 方法，并结合了强大而准确的求根算法。虽然前者在处理分层结构时克服了数值不稳定性，但后者在复杂域中找到色散方程的所有根，提供完整的三维 (3D) 色散曲线。在通过半解析有限元 (SAFE) 方法对完美界面情况验证所提出的公式后，将本解决方案应用于分析具有不完美界面的双层层压板的色散曲线和模式形状。数值例子展示了在具有不完美界面的双层中从完美界面到完全分层的波浪特征的详细演化机制。本文提出的结果为指导原位监测波形和频散曲线从完美界面到完全分层的演变过程提供了重要的见解。数值例子展示了在具有不完美界面的双层中从完美界面到完全分层的波浪特征的详细演化机制。本文提出的结果为指导原位监测波形和频散曲线从完美界面到完全分层的演变过程提供了重要的见解。数值例子展示了在具有不完美界面的双层中从完美界面到完全分层的波浪特征的详细演化机制。本文提出的结果为指导原位监测波形和频散曲线从完美界面到完全分层的演变过程提供了重要的见解。