The in-plane shear failure of transversely stiffened thin plates

• The post-buckled shear response of stiffened plates with plain flat outstands is determined.
• In-plane shear displacement loading is applied using multi-point constraint.
• General, local and transitional shear buckling has been considered.
• Mode jumping is shown to cause an abrupt loss and then recovery of in-plane shear stiffness.
• In-plane shear displacement facilitates the prediction of elasto-plastic unloading.

This paper examines the response of stiffened plates with plain flat outstands when subjected to in-plane shear loading in the form of applied in-plane shear displacement. The buckling and post-buckling failure capabilities of thin plates subjected to in-plane shear, can, of course, be improved through the introduction of stiffening elements whose flexural and torsional rigidities can contribute significantly towards a more stabilised structural system. This paper details appropriate suitable finite element modelling strategies and procedures to enable the determination of the post-buckled failure response of the stiffened shear panels and to highlight the significant influence of the stiffeners. The modelling procedures are able to describe the complete loading history of the stiffened panel structures from the onset of initial buckling through the elastic post-buckling phase of behaviour involving the considerable interaction between plate and stiffener and then through initial material yielding and yield propagation to ultimate conditions and elasto-plastic unloading.