Optimized FRP Wrapping Schemes for Circular Concrete Columns under Axial Compression
Publication: Journal of Composites for Construction
Volume 19, Issue 6
Abstract
This study investigates the behavior and failure modes of fiber-reinforced polymer (FRP) confined concrete wrapped with different FRP schemes, including fully wrapped, partially wrapped, and nonuniformly-wrapped concrete cylinders. By using the same amount of FRP, this study proposes a new wrapping scheme that provides a higher compressive strength and strain for FRP-confined concrete, in comparison with conventional fully wrapping schemes. A total of 33 specimens were cast and tested, with three of these specimens acting as reference specimens and the remaining specimens wrapped with different types of FRP (CFRP and GFRP) by different wrapping schemes. For specimens that belong to the descending branch type, the partially-wrapped specimens had a lower compressive strength but a higher axial strain as compared to the corresponding fully-wrapped specimens. In addition, the nonuniformly-wrapped specimens achieved both a higher compressive strength and axial strain in comparison with the fully-wrapped specimens. Furthermore, the partially-wrapping scheme changes the failure modes of the specimens and the angle of the failure surface. A new equation that can be used to predict the axial strain of concrete cylinders wrapped partially with FRP is proposed.
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Acknowledgments
The authors would like to acknowledge the technical assistance of Messrs. Alan Grant, Cameron Neilson, Fernando Escribano, Ritchie McLean, and Colin Devenish. The contribution of Mr. Elliot Davison is greatly appreciated. Furthermore, the first author would like to thank the Vietnamese Government and the University of Wollongong for the support of his full Ph.D. scholarship.
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Information & Authors
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Published In
Journal of Composites for Construction
Volume 19 • Issue 6 • December 2015
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Dec 14, 2014
Accepted: Feb 17, 2015
Published online: Mar 31, 2015
Discussion open until: Aug 31, 2015
Published in print: Dec 1, 2015
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