Brittle fracture criterion for mixed I - II type of sharp V-notch

Based on the maximum circumferential stress and the Seweryn-Novozhilov criterions, the brittle fracture criterion for mixed sharp I-II type of V-notches is proposed according to the singular stress fields, and the crack is considered as the V-notch with zero open angle, thus the fracture criterion for crack problems is unified with that of V-notch. To verify the validity, tensile experiments were carried out on several kinds of V-notched PMMA specimens. Following the criterion, the predicted crack orientations and critical loads for the double-edge V-notched specimens in some references are compared with the experimental observations to ensure the engineering applications.