Rapid Design and Analysis of Bonded Composite Joggle Lap Joints

Abstract

Progressive failure analysis to determine the strength and damage tolerance of joggle lap joints containing pre-existing cracks was performed using the finite element method and virtual crack closure technique. Two adhesive, and four adherend, thicknesses were considered. Two pre-cracked configurations were considered that contained 0.25 in. long placed at the top adhesive/adherend interface or inside the laminate in the joggle region. The joints with the adhesive cracks exhibited stable crack growth followed by a transition into unstable crack growth. Meanwhile, the advancement of the interlaminar crack was entirely unstable. The line load strength of the joints displayed substantial sensitivity to changes in the thickness of the adherend. However, while the adhesive crack also was affected by changes in the thickness of the adhesive, the interlaminar crack was relatively insensitive to these changes.