Inelastic buckling of continuous steel beam-columns

Abstract This paper describes an experimental study of the inelastic flexural-torsional buckling behaviour of restrained continuous beam-columns typical of those found in multi-storey steel frames. Nine specimens were tested (and five re-tested) under a variety of loading conditions to provide experimental data on the effects of force and moment distribution, continuity, and end restraints. The experimental data will provide benchmark results for future theoretical analyses on the inelastic buckling behaviour of continuous beam-columns. Results presented include failure load combinations, variations of in-plane and out-of-plane displacements with applied load, measurements of geometrical and material imperfections, and results of subsidiary tests to determine the full plastic moment and squash load. A preliminary assessment of present design rules for beam-columns is carried out.