Efficient CFRP Strap Configurations for the Shear Strengthening of Reinforced Concrete T-Beams
Publication: Journal of Composites for Construction
Volume 13, Issue 1
Abstract
A prestressed carbon fiber-reinforced polymer (CFRP) strap retrofitting system has been found to significantly enhance the shear capacity of existing reinforced concrete beams. In previous studies, the CFRP straps were supported on metal pads placed on the top and bottom of a beam necessitating top surface access. The goal of the current work was to develop a system where the straps were installed from underneath a slab without compromising the strengthening efficiency. A series of T-beam experiments was conducted where the CFRP straps were inserted through holes that were drilled from below the flange, thereby avoiding the need for access to the top surface. The depth of penetration of the CFRP straps into the compression flange, the concrete strength, the CFRP strap spacing, the presence of holes in the compression flange, and the size of the loading pads were all found to affect the shear performance. Using the most successful installation technique, the resulting CFRP strengthened beam failed at a load that was approximately 50% higher than that of an unretrofitted control beam.
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Acknowledgments
The writers thank EMPA for their support of this project. The first writer is also indebted to the Cambridge Commonwealth Trust as well as Universities United Kingdom for providing financial assistance during the course of his studies.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 13 • Issue 1 • February 2009
Pages: 45 - 52
Copyright
© 2009 ASCE.
History
Received: Jan 22, 2008
Accepted: May 7, 2008
Published online: Feb 1, 2009
Published in print: Feb 2009
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