It was experimentally shown that transverse stitching can provide an over 20 percent improvement in the strength of composite single-lap joints manufactured using the Resin Transfer Moulding (RTM) process. In this study, an analytical model is presented to predict the strength of the RTM single-lap joints with and without transverse stitching. Simple formulas are used to calculate the energy release rates of mode I and II using longitudinal membrane force and bending moment in a continuous adherent at an overlap end. The strengths of single-lap joints are determined using an interactive mixed-mode based failure criterion. A good correlation between the measured and the predicted failure loads validates the present analytical model.

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