Biaxial Bending Tests with or without Torsion

The results of an elastic and inelastic experimental study of biaxially loaded thin-walled mild steel beams with or without torsion have been presented. Laboratory tests conducted on 24 I-section beams with different lengths, cross-sectional orientations, and loading arrangements show good agreement with the theory presented previously by the writers. It is found that for a biaxially loaded beam with or without torsion, the load-carrying capacity about a stronger axis may be quite sensitive to the magnitude of loads applied or induced about the orthogonal weak axis. Also, the presence of a torque may reduce dramatically the bending moment capacity of a biaxially loaded beam.