Strength improvement by mean of adherend notching and adherend taper in the adhesive single lap joints

In this paper, in order to evaluate the strength improvement of adhesive single lap joints (SLJs), two kinds of adherend geometrical modifications were studied numerically and experimentally. Adherend tapering and adherend notching were considered as the SLJ modification approaches. The taper angle was assumed so that the whole overlap length covered by the taper. On the other side, the optimum values for depth, width and distance from overlap ends as the major notch parameters were acquired by using finite element simulation. Then, the simulated SLJs including an unmodified joint and the modified ones with taper and notch were fabricated and experiments were performed on them. The experiments revealed that both adherend tapering and adherend notching modification methods increase the SLJs strength significantly. In addition, the failure loads of the SLJs with taper modification are a bit less than the failure loads of the ones with notch modification. A similar observation was seen in the results of finite element analyses. The finite element analysis and the experimental results showed that both outer notch and taper modification method could increase the strength of the SLJs significantly.