Corrosion Pillowing Stresses in Fuselage Lap Joints

Abstract

Finite element techniques were used to determine the effect that pillowing, caused by the presence of corrosion products, has on the stress in fuselage lap joints. The stress caused by the internal pressure and the riveting process were taken into account, and the fuselage curvature was ignored. The results show that the joint stress increases as the pillowing increases (i.e., material loss increases). It is shown that pillowing can significantly increase the stress in a lap joint for material loss below the detection limit of current nondestructive inspection techniques, thus increasing the risk of premature cracking.