Consistent and Simplified Direct Strength Method for Design of Cold-Formed Steel Structural Members under Localized Loading
Publication: Journal of Structural Engineering
Volume 146, Issue 6
Abstract
The direct strength method (DSM) is a newly developed design method for cold-formed steel members due to its reliability and consistency. It has been well developed and incorporated in the North American Specification and the Australian/New Zealand Standard for the design of cold-formed steel members under compression, bending, and recently, in shear. To date, there are no DSM rules for the design of cold-formed members under localized loading resulting in the web-crippling phenomenon. Recent literature has attempted to propose the DSM design equations for four localized loading cases including the interior one-flange (IOF), end one-flange (EOF), interior two-flange (ITF), and end two-flange (ETF) loading cases specified in the design specifications/standards. However, these proposed DSM equations were calibrated differently depending on the types of loading cases and geometric shapes of the cross-sections by varying coefficients and exponents in the DSM equations. In this paper, consistent and simplified DSM equations previously proposed by the authors are explained and calibrated for use in the design specifications/standards. They include new plastic mechanism models developed for determining the yield load and also cover the design of sections in the inelastic reserve range as observed. Detailed explanations of the yield load () component and references to computing the buckling load () component are given. A design example is also included.
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Acknowledgments
The authors acknowledge funding for this project provided by the Australian Research Council Discovery Project Grant DP110103948. The first author received scholarships provided from Vietnamese Government (VIED 911 scheme) and supplemental scholarship from School of Civil Engineering, the University of Sydney.
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Published In
Journal of Structural Engineering
Volume 146 • Issue 6 • June 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Nov 28, 2018
Accepted: Oct 15, 2019
Published online: Mar 25, 2020
Published in print: Jun 1, 2020
Discussion open until: Aug 25, 2020
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