Experimental and numerical study of stainless steel I-sections under concentrated internal one-flange and internal two-flange loading

The behaviour and design of stainless steel I-section beams under concentrated transverse loading are investigated in this study. Twenty-four experiments on stainless steel I-sections, formed by the welding of hot-rolled plates, were performed. The tests were conducted under two types of concentrated transverse loading – internal one-flange (IOF) and internal two-flange (ITF) loading. The experimental set-up, procedure and results, including the full load-displacement histories, ultimate loads and failure modes, are reported. A complementary nonlinear finite element modelling study was also carried out. The models were first validated against the results of the experiments. A parametric investigation into the influence of key parameters such as the bearing length, web slenderness and level of coexistent bending moment, on the structural response was then performed. Finally, an assessment of current design provisions for the resistance of stainless steel welded I-sections to concentrated loading is presented. The results show that the current design formulae yield safe-sided, but generally rather scattered and conservative capacity predictions, with considerable scope for further development.