Buckling of Composite Flanges in Partially Disbonded Adhesive Joints

Abstract

This paper contributes newly developed closed-form buckling solutions for generic one-edge-free problems common to partially disbonded composite structures. These solutions are shown to be accurate by comparison with experimentally measured buckling loads which are also reported in this paper. The buckling of partially disbonded regions in adhesive joints is a safety concern due to the potential for ensuing buckling-driven disbond growth. In order to design structures to be tolerant to these flaws, closed-form expressions that predict buckling load have been developed based on a one-edge-free buckling model. Comparison of the closed-form predictions with the finite element results verifies the accuracy of the solutions. Validation of these analyses was achieved by comparison with the experimentally determined buckling loads. These were measured to fall within a range of predicted values, as defined by the choice of boundary condition opposite the disbonded flange-free-edge: either clamped or simply-supported. Assumption of either boundary condition provides upper- and lower-bound predictions of buckling in partially disbonded joint flange configurations.