Numerical Investigation on the Axial Load Behaviour of Polygonal Steel Tube Columns

Abstract

Hollow steel tubes members with different properties are being increasingly used for structural applications, such as columns in frame structures, roof structures, truss columns, and other applications. These structural members are primarily subjected to compressive and flexural loading. Due to the insufficient studies regarding the influence of the cross-section’s shapes on the axial load behaviour of hollow steel columns, this study has presented eight different cross-sections shapes and has indicated their effect on the axial load behaviour of the polygonal hollow steel columns. Eighty different FE models have been designed and analysed to find the effect of the cross-section shape, thickness, length, and materials on the axial load behaviour of the polygonal hollow steel columns. The FE results have proved that the cross-sectional shapes affect the ultimate axial load behaviour of the hollow steel tubes by 14%. The highest ultimate axial load resistance recorded by Rec. model has been followed by Squ. unlike Cir. model, which has presented the lowest ultimate axial load resistance followed by Ova. model. This study also demonstrates that when the cross-sectional shape of the hollow steel tubes is near to a rectangular shape, the ultimate axial load resistance will be higher, while, if it is near to a circular shape then low ultimate axial load has been registered. Moreover, there is a small effect of the steel tube thickness, length and material on the axial load behaviour of the hollow steel tubes with different cross-sectional shapes, with almost -2% to -14%.