The fracture behavior of random chopped-strand, glass-fiber reinforced SMC composites was studied. Experiments were conducted on notched SMC-R50 composite plates subjected to in- plane loading. Fracture mechanics analyses based on recently developed conservation laws of solid mechanics were performed to evaluate notch-tip stress intensities in the specimens. Fracture toughnesses, KIQ and KIIQ, of this material under individual mode-I and mode-II loading were determined. Fracture tests and subsequent analyses were also conducted on the notched SMC- R50 subjected to combined-mode loading. Mixed-mode fracture criteria were investigated for the random short-fiber composite. The suitability of the Whitney-Nuismer two-parameter model was also examined for determination of notched SMC composite strength.
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