Tests and design of fixed-ended cold-formed steel plain angle columns

Abstract

This paper presents a series of tests on cold-formed steel plain (unstiffened) angle columns compressed between fixed ends. The test specimens were brake-pressed from high strength structural steel sheets. Tests were performed over a range of lengths such that column curves could be obtained. Geometric imperfections and material properties of the specimens were measured. The test strengths are compared with the design strengths calculated using the American Specification and Australian/New Zealand Standard for cold-formed steel structures. The required additional moment as specified in the Specification and Standard was not included in calculating the design strengths for slender and nonslender angle sections. It is shown that the design strengths predicted by the Specification and Standard are generally very conservative. Design equations for cold-formed steel plain angle columns are proposed, which are modified from the current design equations in the Specification and Standard. It is shown that the proposed design rules provide much more accurate results compared with the current design rules for both slender and nonslender fixed-ended angle sections. A reliability analysis was performed to assess the reliability of the current and proposed design rules.