In this paper it is proposed a phenomenological framework to perform the failure analysis of a family of adhesive single lap joints. The theory is conceived for adhesives with quasi-brittle behaviour and highly resistant adherends. The main goal is to predict the rupture force using model equations that combine enough mathematical simplicity to allow their usage in engineering problems with the capability of describing a complex nonlinear mechanical behaviour. The material constants that appear in the model equations are identified for an adhesive/adherend system consisting of ASTM A36 steel plates bonded with an epoxy/ceramic composite. Results from experimental tensile testing of joints with different bonded areas were compared with model prediction showing a good correlation.