Structural behavior of extreme thick-walled cold-formed square steel columns

This paper describes a study on the extreme thick-walled cold-formed square columns which are manufactured from circular to square shape, of which the width was 800 mm and the thickness was 22 mm. A systematic investigation of material behavior, residual stress distribution, and axial compression performance was performed numerically and experimentally. Results demonstrate thefollowing.1) The material properties of cold-formed columns manufactured by indirect method are clearly changed because of the cold-formed processes and are more uniform than those of cold-formed columns manufactured by direct method. 2)The extreme thick-walled cold-formed square columns work well under axial compression. 3) The residual stresses at the middle and corner parts of extreme thick-walled cold-formed square columnsareapproximately95 and 210 MPa, respectively.