Design of Angle Columns with Locally Unstable Legs
Publication: Journal of Structural Engineering
Volume 131, Issue 10
Abstract
The paper addresses the design of angle section columns whose legs are slender and thus subject to local buckling in their ultimate limit state. For such slender angle sections, the local buckling mode is identical to the torsional mode and traditional design procedures become excessively conservative because they account for the torsional (local) buckling mode twice. The paper describes design methods for slender equal-leg angles which ignore torsion in determining the overall buckling stress and use recently presented effective width equations to accurately determine the bending capacity of angle sections, as required in the beam–column design approach. The shift in the effective centroid resulting from local buckling is determined from the actual stress distribution, as obtained using Stowell’s classical solution, rather than the effective cross section. The columns are assumed to be simply supported and thus allowed to rotate about their principal axes.
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Acknowledgments
This paper was prepared while the writer was on study leave at the University of Trento. The facilities provided by the University of Trento are gratefully appreciated. Thanks also go to Professor Gregory Hancock for his comments to the manuscript.
References
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Information & Authors
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Copyright
© 2005 ASCE.
History
Received: Aug 26, 2003
Accepted: Mar 1, 2004
Published online: Oct 1, 2005
Published in print: Oct 2005
Notes
Note. Associate Editor: Sherif El-Tawil
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