Steel-concrete composite structures are used widely in the current construction of bridges and multistory buildings. Experimental and numerical studies were conducted to investigate the behavior of composite cold formed steel columns under axial load only with lack of experimental investigation on composite cold formed steel columns under lateral loads. This paper conducted to investigate experimentally and numerically the behavior of composite cold formed steel columns under axial and lateral loads. Five specimens were tested to evaluate the failure modes, strains development and load-deformation histories in the steel tube. Finite element (FE) models using ANSYS Workbench were developed and verified against experimental results. The verified FE will be used in future by the authors to study the influence of key parameters that control the behavior of composite cold forms steel columns, including cross sections, fastener spacing, fastener length, yield strength of steel, on the load carrying capacity. It was observed from the obtained results that composite column with sigma section show better behavior than C section because of the web and flange for the sigma section are both stiffened. The embedded fasteners length of 50mm enhanced load carrying by 13% compared to 30mm length.

Keywords : Composite Columns, Finite Element Model, Cold Formed Steel, Axial Loads, Lateral Loads.