Abstract The mode I fracture parameters for an orthotropic body are directly calculated from full-field deformation measurements provided by Digital Image Correlation (DIC). Three complementary and direct approaches are evaluated and compared: (i) the determination of the Stress Intensity Factor (SIF) by fitting the displacement field using the analytical expression proposed by Lekhnitskii; (ii) the determination of the J-Integral by using the Energy Domain Integral (EDI) formulation on the raw DIC data; and (iii) the calculation of the J-Integral using the EDI approach on the displacement data fitted using Lekhnitskii’s formulation. A comparative experimental study is performed by testing an IM7/8552 cross-ply laminate, and the effect of different parameters is analysed and discussed. The outcomes of this work show that, if an accurate choice of the parameters is performed, the different approaches lead to the same results.

中文翻译：

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正交各向异性材料I型断裂参数的数字图像相关实验测定

摘要 正交各向异性体的 I 型断裂参数直接由数字图像相关 (DIC) 提供的全场变形测量计算得出。评估和比较了三种互补和直接的方法： (i) 通过使用 Lekhnitskii 提出的解析表达式拟合位移场来确定应力强度因子 (SIF)；(ii) 通过对原始 DIC 数据使用能量域积分 (EDI) 公式确定 J 积分；(iii) 使用 EDI 方法对使用 Lekhnitskii 公式拟合的位移数据计算 J 积分。通过测试 IM7/8552 交叉层层压板进行了对比实验研究，并分析和讨论了不同参数的影响。这项工作的结果表明，