Buckling and post-buckling of thin-walled stiffened panels: modelling imperfections and joints

This paper explores the effect of different modelling strategies to represent geometrical imperfections and joints in flat thin-walled stiffened panels during buckling and post-buckling. Compression tests were performed on aircraft grade aluminium alloy panels jointed to L-shape stiffeners using rivets with digital image correlation used to monitor out-of-plane deformations, mode shape changes and failures such as stiffener debonding. Experiments were replicated using finite element analysis employing different levels of complexity to model geometric imperfections and joints. The advantages and limitations of these strategies are discussed and recommendations are made