Plate buckling in the framework of a modified RRD concept from shell buckling

The Eurocode EN 1993-1-5 rules the proof against plate buckling of unstiffened and stiffened plated structures. Alternatively, the proof can be carried out numerically using the new Eurocode prEN 1993-1-14. However, the numerical proof with the Finite-Element Method (FEM) can be very time-consuming due to the high modelling effort and the verification and validation process of the model. This is where the Reference Resistance Design (RRD) concept from shell buckling, ruled in EN 1993-1-6, comes in. The idea of the RRD concept is to perform numerical simulations and obtain generalized capacity curves based on these resistances. As the application of the RRD concept to plate buckling problems is new, the question arises of whether the RRD concept can map the different coupled stability phenomena, like local and global plate buckling, post-critical behaviour, column-like behaviour, torsional buckling of open stiffeners, etc. Therefore, extensive numerical studies were carried out on the typical case of longitudinally stiffened plates with flat stiffeners. The numerical resistances were used as the basis for determining the RRD parameters of the generalized capacity curves. It was found that the RRD concept is suitable for mapping the complex load-bearing behaviour of stiffened plated elements. Nevertheless, larger deviations were found for the current version of the RRD concept, which is why a modified version is proposed. The obtained RRD parameters are given as supplemental text files to this paper. The RRD concept appears to be a simple alternative to the proofs from EN 1993-1-5. The time-consuming determination of the RRD parameters is a significant disadvantage, but the RRD concept can be very helpful in cases not covered by EN 1993-1-5.