Fracture Criterion of Woven Glass-Epoxy Composite Using a New Modified Mixed-Mode Loading Fixture

In this study, experimental and numerical investigation of the interlaminar fracture behavior of woven glass-epoxy composite was performed under static mixed-mode loading conditions. A new modified mixed-mode loading fixture was employed for this purpose. Woven glass-epoxy composite sheet was produced by hand lay-up method and post-cured in an autoclave set. Butterfly samples were prepared by saw water machine. Mixed-mode fracture tests from pure mode-I to pure mode-II were performed. A finite element analysis was performed and nondimensional stress intensity factors of butterfly samples were computed and a polynomial fit was proposed to evaluate the stress intensity factors of an interlaminar crack subjected to various mixed-mode loadings using new designed fixture. The results indicated that the composite material used in this study is tougher in shear loading conditions and weaker in tensile loadings. For studied composite material, the interlaminar mixed-mode fracture data were according to the strain energy release rates by power-law criterion with the exponents m = 0.38, n = 1.32.