Abstract This paper, for the first time in literature, formulated and validated a three-dimensional, nonlinear augmented finite element method (3D A-FEM) that can account for multiple crack evolution in laminated composites under large deformation. The 3D A-FEM accounts for all major cracking events (intra-ply matrix cracking, fiber rupture/kinking, and inter-ply delamination) with explicit cohesive cracks. The computational scheme is achieved by coupling the 3D A-FEs for intra-ply cracks with 3D cohesive interface elements for inter-ply delamination. The strong discontinuities of both intra- and inter-ply cracks are explicitly represented by the geometrically nonlinear cohesive zone models (CZMs). The numerical capability is demonstrated by several benchmark tests with both in-plane and out-of-plane loadings. Results show that the A-FEM predicted progressive damage processes, including the arbitrary initiation of multiple cracks and their nonlinearly coupled progression with delamination all the way up to the final catastrophic failure, are all in good agreement with experimental results.

中文翻译：

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复合材料层合板任意开裂的 3D 几何非线性增强有限元方法

摘要 本文首次在文献中制定并验证了一种三维非线性增强有限元方法 (3D A-FEM)，该方法可以解释大变形下层压复合材料中的多重裂纹演化。3D A-FEM 解释了具有显性内聚裂纹的所有主要开裂事件（层内基体开裂、纤维断裂/扭结和层间分层）。计算方案是通过将用于层内裂纹的 3D A-FE 与用于层间分层的 3D 内聚界面元素耦合来实现的。层内和层间裂纹的强烈不连续性由几何非线性内聚区模型 (CZM) 明确表示。数值能力通过具有平面内和平面外载荷的几个基准测试来证明。