Distortional Buckling of Cold-Formed Steel Flanges under Stress Gradient
Publication: Journal of Structural Engineering
Volume 146, Issue 9
Abstract
The strength of cold-formed steel beams with stiffened flanges may be controlled by distortional buckling. Buckling stress prediction methods have been developed for flanges under uniform compression. However, channel sections are commonly used where bending occurs about the minor axis with flanges under a stress gradient, such that the edges that are in compression and the flanges may experience distortional buckling. Current design specifications do not explicitly address this failure mode, which could lead to unsafe designs. This paper presents and verifies an analytical approach for distortional buckling stress prediction for flanges under a stress gradient. The approach is consistent with the design method used for flanges under uniform compression in the American Iron and Steel Institute (AISI) specification for the design of cold-formed steel members. This consistency facilitates a straightforward incorporation into the design specification.
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Data Availability Statement
Some or all data, models, or code generated or used during the study are available from the author by request. Some of the data, models, or code generated or used during the study are proprietary or confidential in nature and may only be provided with restrictions.
Acknowledgments
The author would like to thank Dr. Benjamin Schafer of Johns Hopkins University for his contribution to this study. His innovative developments referenced in this study became the foundation and inspiration for these new developments. Furthermore, his review and valuable advice on this work helped to refine and improve this paper.
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Published In
Journal of Structural Engineering
Volume 146 • Issue 9 • September 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Oct 24, 2019
Accepted: Apr 8, 2020
Published online: Jun 29, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 29, 2020
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