Design Strengths of Cold‐Formed Channels in Bending and Torsion
Publication: Journal of Structural Engineering
Volume 120, Issue 5
Abstract
Channel sections in flexure, when not attached to deck or sheeting, are designed according to the American Iron and Steel Institute's equations for lateral‐torsional buckling. These formulas assume an unbraced length with equal and opposite end moments, and only torsional restraints at the braces. These formulas tend to overestimate the buckling strength in some cases, especially where there are two or more intermediate braces within a span length. The reason for this is that the failure mode may be something other than lateral‐torsional buckling. In fact, tests have shown that highly braced members usually fail by distortional buckling of the flange‐lip intersection at a braced point. The present paper reports a series of experiments on channels with various bracing schemes and offers a mathematical prediction model for the ultimate strength of a channel in flexure.
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Copyright © 1994 American Society of Civil Engineers.
History
Received: Oct 9, 1992
Published online: May 1, 1994
Published in print: May 1994
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