Inhibiting Steel Brace Buckling Using Carbon Fiber-Reinforced Polymers: Large-Scale Tests
Publication: Journal of Structural Engineering
Volume 135, Issue 5
Abstract
A new method is proposed for inhibiting the buckling response of steel braces. The strengthening technique involves attaching a core comprised of mortar blocks to the braces and then wrapping the entire system with carbon fiber-reinforced polymer (CFRP) sheets. An advantage of this method is that the technology can be applied in situ by a single individual with minimal training. Test results of seven specimens subjected to reversed axial loading show that it is feasible to achieve buckling restrained response up to 2% interstory drift. Other than the number of longitudinal fiber layers, it is observed that performance of the strengthening scheme depends upon the size of the core material, the presence of bond between the steel plate and core material, the existence of extra stitch plates for double angle members, and the presence of transverse CFRP layers at the member ends. It is also observed that double angle braces benefit more from the strengthening scheme than single angle braces, which are prone to premature out-of-plane buckling.
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Acknowledgments
The research presented in this paper was supported in part by the Department of Civil and Environmental Engineering at the University of Michigan and the Michigan Department of Transportation. Carbon fiber polymer sheets and epoxy were provided by Degussa, Inc. Any opinions, findings, conclusions, and recommendations expressed in this paper are those of the writers alone and do not necessarily reflect the views of the sponsoring agencies.
References
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 135 • Issue 5 • May 2009
Pages: 530 - 538
Copyright
© 2009 ASCE.
History
Received: Jun 17, 2008
Accepted: Oct 27, 2008
Published online: Mar 2, 2009
Published in print: May 2009
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