Cohesive element (CE) is a well‐established finite element for fracture, widely used for the modeling of delamination in composites. However, an extremely fine mesh is usually needed to resolve the cohesive zone, making CE‐based delamination analysis computationally prohibitive for applications beyond the scale of lab coupons. In this work, a new CE‐based method of modeling delamination in composites is proposed to overcome this cohesive zone limit on the mesh density. The proposed method makes use of slender structural elements for the plies, a compatible formulation with adaptive higher‐order integration for the CEs, and the corotational formulation for geometrically nonlinear analysis. The proposed method is verified and validated on the classical benchmark problems of Mode I, II, mixed‐mode delamination, a buckling‐induced delamination problem and a double‐delamination problem. The results show that elements much larger than the cohesive zone length can be used while retaining accuracy.

中文翻译：

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克服复合材料分层中的粘聚区限制：使用细长结构元素和高阶自适应积分进行建模

粘结单元（CE）是一种公认​​的断裂有限元，广泛用于复合材料分层的建模。但是，通常需要使用极细的网格来解决粘结区域，这使得基于CE的分层分析在计算上无法用于超出实验室试样规模的应用。在这项工作中，提出了一种新的基于CE的复合材料分层建模方法，以克服网格面积上的粘聚区限制。所提出的方法利用了纤薄的结构元件，适用于CE的具有自适应高阶积分的兼容公式以及用于几何非线性分析的修正公式。该方法针对I，II模式，混合模式分层，屈曲引起的分层问题和双重分层问题。结果表明元素很多较大的比内聚带长度，同时保留精度来使用。