Flexural Strengthening of RC Beams with Prestressed CFRP Sheets: Development of Nonmetallic Anchor Systems
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Volume 12, Issue 1
Abstract
This paper presents a novel anchoring technique for strengthening reinforced concrete beams with prestressed carbon fiber- reinforced polymer (CFRP) sheets. Permanent steel anchors are commonly used for the application of prestressed CFRP sheets. The steel anchors are, however, susceptible to corrosion and may not blend into the aesthetics of the original structure. As a result, it may be preferable to remove the steel anchors after transferring the required prestress to the structure with minimal losses of sustained prestress. A technique for replacing the steel anchors with nonmetallic anchors is investigated and reported herein. Nine doubly reinforced concrete beams are tested with various types of nonmetallic anchor systems such as nonanchored U-wraps, mechanically anchored U-wraps, and CFRP sheet-anchored U-wraps. The developed nonmetallic anchorages successfully transfer the sustained prestress in the CFRP sheets with insignificant prestress losses. A closed-form solution for the transfer of prestress is developed and compared to the experimental results.
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Acknowledgments
The writers wish to acknowledge the support of the Department of National Defence (DND) of Canada through the Military Engineering Research Group (MERG) at the Royal Military College of Canada (RMC), and the financial support of Intelligent Sensing for Innovative Structures Network (ISIS Canada), the Natural Sciences and Engineering Council of Canada (NSERC), and Queen’s University. The contribution of the RMC technical staff is greatly appreciated as well.
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Published In
Journal of Composites for Construction
Volume 12 • Issue 1 • February 2008
Pages: 35 - 43
Copyright
© 2008 American Society of Civil Engineers.
History
Received: Jul 27, 2006
Accepted: Nov 2, 2006
Published online: Feb 1, 2008
Published in print: Feb 2008
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