Local buckling behaviour of longitudinally stiffened stainless steel plate girders under combined bending and shear

Abstract

This paper presents a comprehensive experimental and numerical investigation into the local buckling behaviour of longitudinally stiffened stainless steel plate girders under combined bending moment and shear force. Five plate girders configurated with longitudinal stiffeners with different geometrical proportions and vertical positions were fabricated from austenitic and duplex stainless steel plates. Initial geometric imperfections and material properties were measured, and all plate girders were tested to failure under a three-point loading configuration. The critical buckling strengths, ultimate capacities and failure modes were carefully analysed. Elaborate finite element (FE) models were developed and validated against the test results, and were then used to conduct parametric studies to generate further structural performance data over a wide range of cross-sectional properties, including various geometrical proportions and positions of longitudinal stiffeners, and loading combinations. The obtained test and FE results were utilised to assess the applicability of existing M–V interaction design methods in EN 1993-1-5 and that proposed by Jáger et al. for longitudinally stiffened plate girders. It was indicated that these two M–V interaction curves coupled with the design provisions in EN 1993-1-4 for determining the bending and shear endpoints, offer safe-sided predictions with a good level of consistency and accuracy, for longitudinally stiffened stainless steel plate girders under combined bending and shear. The reliability of these design approaches was further confirmed by statistical analysis.