Analysis of Intensity of Singular Stress Field at the Stepped-Lap Joint

Abstract

In this paper, the intensity of a singular stress field (ISSF) is focused and newly analyzed for a stepped-lap joint, and the adhesive strength is considered in terms of the ISSF. In this problem, it is necessary to analyze the two different singular stress fields at the interface end point A and each interface corner point B_i (i = 1,2…Ns-1, Ns = the number of steps) on the adhesive surface. Therefore, two different reference solutions are used in this study. The reference problem for point A is a butt joint having the same adhesive layer thickness as the stepped-lap joint. The reference problem for point B_i is chosen as a single rectangular fiber in an infinite plate under remote tension. In order to investigate the effect of the number of steps, Ns, on the ISSF of the stepped lap joint, four models with different numbers of steps are calculated. By comparing the stress distributions, we found that the ISSF at point A is larger than that at point B_i. Moreover, we also show that the ISSF at point A decreases with an increasing number of steps, Ns, but there is almost no change of the ISSF at point B_i.