Shear buckling behaviour of welded stainless steel plate girders with transverse stiffeners

The shear buckling behaviour of welded stainless steel plate girders with transverse stiffeners has been experimentally and numerically investigated in this paper. A total of seven plate girders with rigid/non-rigid end posts were fabricated from hot-rolled stainless steel plates, and each of the plate girders was subjected to a concentrated load at mid-span. The shear buckling characteristics and postbuckling behaviour were observed. Prior to testing, the initial local geometric imperfections and the material properties were accurately measured. The critical shear buckling strengths of the web plates were determined from the recorded surface strains and out-of-plane deflections, which were further compared with theoretically predicted values from elastic and inelastic assumptions. By using the general finite element (FE) software package ABAQUS, elaborated FE models were developed and validated against the obtained test results and other available existing test data. Upon validation of the FE models, parametric studies were subsequently carried out to explore the influences of initial local geometric imperfections, web aspect ratios, end post conditions, and material properties over a wide range of web slendernesses. The obtained test/FE results, together with other existing test data, were summarised to evaluate the current codified provisions in GB 50017, EN 1993-1-5, EN 1993-1-4, EN 1993-1-4+A1 and the design proposals from Estrada et al. Based on the test and numerical results, an alternative design approach that could account for the material non-linearity and rigid and non-rigid end posts has been proposed, which provides accurate and reasonable strength predictions for stainless steel plate girder with transverse stiffeners.