Summary Powell‐Sabin B‐splines, which are based on triangles, are employed to model cohesive crack propagation without a predefined interface. The method removes limitations that adhere to isogeometric analysis regarding discrete crack analysis. Isogeometric analysis requires that the initial mesh be aligned a priori with the final crack path to a certain extent. These restrictions are partly related to the fact that in isogeometric analysis, the crack is introduced in the parameter domain by meshline insertions. Herein, the crack is introduced directly in the physical domain. Because of the use of triangles, remeshing and tracking the real crack path in the physical domain is relatively standard. The method can be implemented in existing finite element programmes in a straightforward manner through the use of Bézier extraction. The accuracy of the approach to model free crack propagation is demonstrated by several numerical examples, including discrete crack modelling in an L‐shaped beam and the Nooru‐Mohamed tension‐shear test.

中文翻译：

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使用 Powell-Sabin B 样条进行内聚断裂分析

摘要 基于三角形的 Powell-Sabin B 样条曲线用于在没有预定义界面的情况下模拟粘性裂纹扩展。该方法消除了有关离散裂纹分析的等几何分析的限制。等几何分析要求初始网格在一定程度上与最终裂纹路径先验对齐。这些限制部分与以下事实有关：在等几何分析中，裂纹是通过网格线插入引入到参数域中的。这里，裂纹直接引入到物理域中。由于使用了三角形，在物理域中重新网格化和跟踪真实裂纹路径是相对标准的。该方法可以通过使用贝塞尔提取以简单的方式在现有的有限元程序中实现。几个数值示例证明了自由裂纹扩展模型方法的准确性，包括 L 形梁中的离散裂纹建模和 Nooru-Mohamed 拉剪试验。