Effects of the adhesive disband on the performances of bonded composite repairs in aircraft structures

In this study, the effects of the adhesive disband on the efficiency of bonded composites repair in aircraft structures were analyzed. The three-dimensional finite element method was used to achieve the objectives of the study. The stress intensity factor at the crack tip was chosen as fracture criteria. The analysis was extended to the single and double symmetric bonded composite patches. The obtained results show that the repair efficiency is negatively influenced if the adhesive disband growths perpendicularly to the crack. In the case of double symmetric patch, the presence of double adhesive disband highly decreases the repair efficiency and increases the risk of adhesion failure between the composite patch and the cracked aluminum structures.