We have developed a model for predicting the tensile strength of discontinuous carbon fiber reinforced polypropylene composites with an open circular hole. To investigate the fracture mechanisms, composite specimens with different open hole diameters were tested in tension, and their fracture morphology was subsequently observed using a scanning electron microscope. Based on fracture surface observations, a Duva–Curtin–Wadley model was chosen as the fiber breakage criterion. This was incorporated into an equivalent inclusion model combined with the Mori–Tanaka theory to predict the tensile strength of the composites. The equivalent material properties together with the Weibull fracture criterion acquired from the tensile-loading experiments on the composites were implemented in a meso-scale finite element simulation package. It was shown that the predicted trend of decreasing tensile strength with increasing open hole diameter was reasonably consistent with the experimentally-obtained data. The discrepancy between the experimental tensile strength and the model predictions was less than 9%, indicating the validity of the simulation model developed in this research.
