Analysis and design of concrete-filled stiffened thin-walled steel tubular columns under axial compression

Longitudinal stiffeners are effective in improving the overall performance of concrete-filled square or rectangular thin-walled steel tubular columns. This paper is concerned with the nonlinear analysis and design of stiffened square stub columns under axial compression. The nonlinear analysis is performed using ABAQUS, a commercially available finite element (FE) program. Close agreement is shown between the test and predicted results in terms of the load-deformation curves and ultimate strength. The column behaviour is investigated and discussed using this modelling. The limit of width-to-thickness ratio for the sub-panels and the rigidity requirement for the stiffeners is discussed. The feasibility using existing design codes to predict the load-carrying capacities of the stiffened composite columns is also dealt with in this paper.