Abstract In this work, a numerical analysis of typical composite bonded repairs is performed aiming to establish a comparison between their performance under quasi-static and high-cycle fatigue loading. The studies include progressive damage analysis employing cohesive zone models suitable for quasi-static and high-cycle fatigue under mixed-mode I+II loading. Five repair geometries, e.g., Single-Strap, Double-Strap, Scarf, One-Stepped and Two-Stepped were analysed under three-point bending loading considering three different overlap lengths. In the quasi-static analysis, the focus was the initial stiffness, peak load and the corresponding displacement. Fatigue studies were executed under load control and under displacement control aiming to determine the fatigue lives. A final research addressed two of the embedded repairs, Scarf and Two-Stepped, reinforced with a bonded patch, which was verified to improve significantly fatigue resistance, especially in the case of the Scarf repair.

中文翻译：

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疲劳载荷下几种复合材料粘接修复的数值比较

摘要 在这项工作中，对典型的复合材料粘接修复进行了数值分析，旨在比较它们在准静态和高周疲劳载荷下的性能。这些研究包括采用适用于混合模式 I+II 载荷下的准静态和高周疲劳的内聚区模型的渐进式损伤分析。在考虑三种不同重叠长度的三点弯曲载荷下分析了五种修复几何形状，例如单带、双带、围巾、单步和两步。在准静态分析中，重点是初始刚度、峰值载荷和相应的位移。疲劳研究是在载荷控制和位移控制下进行的，旨在确定疲劳寿命。最后一项研究解决了两个嵌入式维修，Scarf 和 Two-Stepped，