Axial compression behavior of laced cold-formed steel built-up columns with unstiffened angle sections

Abstract

There are numerous parameters that influence the behavior of built-up steel columns. This paper reports an experimental investigation carried out on cold-formed steel (CFS) built-up columns composed of four unstiffened CFS equal angle sections connected by lacings intermittently along their heights. The man parameters varied in the test specimens were the width of end plate, the lacing slenderness ratio, the chord flat width-to-thickness ratio and the lacing configurations. Six pin-ended test specimens were tested under monotonically increasing concentric axial loading. The test result output viz. ultimate column strengths, load vs. displacement response, mode of failure, and deformed shapes were used to investigate the effect of above-mentioned parameters on the axial behavior of CFS built-up laced columns. The current standards for CFS structures were used to predict the column strengths for the sake of comparison. Furthermore, a numerical validation of the test results was carried out using a finite element software ABAQUS. Test results indicate that the lacing slenderness, the lacing configuration, and the end plate width affect the column behavior in CFS laced built-up columns significantly.