Square and rectangular hollow sections subject to combined actions

A large number of tests on a range of cold-formed square and rectangular hollow sections subjected to pure bending, pure concentrated force and combined bending, and concentrated force are described. The concentrated force is applied by means of a bearing plate that acts across the full flange width of the section. The ratio (γ) of the bearing length to the width of the bearing plate used varies from 0.5 to 1.0 in order to show the effects of the bearing length on the failure loads. The current tests are compared with previous T-joint tests performed at the University of Sydney on similar sections to demonstrate the significant reductions in failure loads and the more severe interaction between bending moment and concentrated force for the tests using bearing plates. The test results are compared with the existing Australian, European, and American design procedures. Improved design procedures are also proposed.