Investigation on Innovative Cold-Formed Steel Built-Up Columns Using Lipped and Unlipped Channels

Cold-formed steel (CFS) columns are broadly used in the construction industry for low-rise buildings because of their lightweight, easy installation, and erection. Back-to-back built-up CFS lipped channel sections and box sections are adopted in CFS structures. In this research, an innovative built-up column consisting of a total of 4-individual CFS channels, in which two are CFS lipped channels, which are arranged back-to-back and connected with the help of screw fasteners, while another two individual channels without lips are placed around the boundary of the back-to-back channel and connected with screw fasteners where flanges of both the channels intersect at specified spacing along the length of the column. Finite element (FE) models are modelled, and buckling analysis is performed through Abaqus 6.14 software by varying the height of the column, while the thickness of the section is constant. The height of four columns adopted as 300, 500, 1000, and 1500 mm, respectively, by varying the slenderness ration. These built-up columns are fabricated and buckling test was conducted. The analytical and experimental results are compared to identify the best performing section.