Effect of humidity absorption by the adhesive on the performances of bonded composite repairs in aircraft structures

In this study, an experimental work was done to analyse the effect of the humidity absorption on the mechanical properties of the adhesive Adekit A140 epoxy. The measured properties were introduced in a finite element model in order to analyse the effects of the humidity absorption on the performances of bonded composites repair in aircraft structures by computing the J integral around the crack tip and the distribution of the adhesive shear stresses. The obtained results show that the adhesive losses its rigidity by the humidity absorption which reduce the repair efficiency but increases the repair durability.