Experimental Assessment of the Adequacy of Numerical Modeling of the Interlayer Crack Resistance of a Laminate Glass-Epoxy Composite under Combined Loading Mode I/II

Abstract—The reliability of numerical modeling of crack growth in a laminate glass-epoxy composite under combined loading by opening (mode I) and shear (mode II) of an interlaminar crack was assessed. According to experimentally determined standard (DCB and ENF) and nonstandard (SLB and OLB) methods for the values of interlayer crack resistance parameters under individual and combined loading modes I and II, the exponent in the Benzeggagh-Kenane equation was calculated as a material constant of a laminated epoxy glass composite. Using this parameter and using the ANSYS application software package within the framework of linear elastic fracture mechanics and the virtual crack closure method, the numerical finite element modeling of interlaminar crack resistance of SLB and OLB type specimens was carried out under a combined loading mode with a different fraction of modes. With an optimal number of elements in a finite element mesh corresponding to a given length of the crack growth trajectory, the numerical modeling provides sufficient accuracy in calculating the limit load of the beginning of crack growth with a minimum amount of calculations and good agreement between the experimentally determined and calculated crack resistance parameters.