Abstract
The aim of this study is to analyse, by the finite-element method, the disbond effect on the variation of the stress intensity factor (SIF) at the crack tip in an aluminium sheet repaired with a boron/epoxy patch. The effects of the width and the height of the disbond on the variation of the SIF at the crack tip are highlighted. The obtained results show that the presence of the disbond area increases the SIF of the repaired crack and the rate of this increase depends primarily on the size of the disbond area. The obtained results allow the development of an analytical model of the asymptotic SIF, which takes account of the disbond effect. This model adds the effect of the disbond of the adhesive layer to the well-known Rose model.