Abstract Elastic-plastic failure of multi-cracked specimens made from epoxy material is studied theoretically and experimentally for the first time under mixed mode I/II loading conditions. Different cracks arrangements are considered for preparing the specimens. For providing different mixed mode I/II loading conditions in the fracture tests on epoxy specimens, different crack inclination angles are considered in the samples. Load-carrying capacities (LCCs) of the multi-cracked specimens are obtained experimentally by performing fracture tests. In order to avoid the complex and time-consuming elastic–plastic failure predictions, the Equivalent Material Concept (EMC) is used in conjunction of the dislocation method and generalized maximum tangential stress criterion to obtain experimental and theoretical fracture parameters. It is demonstrated that the proposed combined approach can provide reliable predictions of fracture toughness and fracture estimation under mixed mode I/II loading.

中文翻译：

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混合模态I/II加载下多裂纹韧性聚合物试样的失效预测

摘要 首次从理论和实验上研究了混合模I/II加载条件下环氧材料制成的多裂纹试样的弹塑性破坏。准备试样时考虑了不同的裂纹排列。为了在环氧树脂试样的断裂试验中提供不同的混合模式 I/II 加载条件，在样品中考虑了不同的裂纹倾角。多裂纹试样的承载能力 (LCC) 是通过进行断裂试验通过实验获得的。为了避免复杂且耗时的弹塑性失效预测，等效材料概念 (EMC) 结合位错方法和广义最大切向应力准则来获得实验和理论断裂参数。