Unstiffened Elements as Limiting Case of Distortional Buckling of Partially Stiffened Elements
Publication: Journal of Structural Engineering
Volume 146, Issue 9
Abstract
Lip stiffened flanges in cold-formed steel compression members may undergo local or distortional buckling depending on the slenderness of the flange and rigidity of the lip. In distortional buckling, the flange-lip assembly moves perpendicular to the flange. The decrease in stiffness (or depth) of the lip increases the vulnerability of such elements to distortional buckling. In the limiting case of zero lip depth, the plate behaves as an unstiffened element. Hence the behavior of the unstiffened element may be intuitively understood as the limiting case of distortional buckling of lip stiffened element as the lip depth tends to zero. In this study, experimental and numerical results are used to show that both elastic buckling and ultimate strength behavior of a uniformly compressed unstiffened element may also be represented as distortional buckling of the lip stiffened element of zero lip depth. In addition to the effective width method, the modified direct strength method equation developed for distortional buckling is also shown to accurately estimate the ultimate strength of uniformly compressed unstiffened elements.
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Data Availability Statement
Data generated or analyzed during the study are available from the corresponding author by request.
Acknowledgments
The first author gratefully acknowledge the financial support provided by the Ministry of Human Resource Development (MHRD), India. The investigation reported in this paper was funded by Science Engineering and Research Board (SERB) Research Grant (No. CRG/2018/001969) from the Department of Science and Technology (DST), Government of India. The second author would like to acknowledge the financial assistance received from this project. The authors also acknowledge Professor Pramod S. Mehta (IIT Palakkad) for his critical comments on the results generated in this study, which helped to improve the quality of 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: Sep 18, 2019
Accepted: Feb 24, 2020
Published online: Jun 22, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 22, 2020
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