Experimental Behavior of Reinforced Concrete Beams Strengthened with Prestressed CFRP Shear Straps
Publication: Journal of Composites for Construction
Volume 11, Issue 4
Abstract
One promising means of increasing the capacity of existing shear-deficient beams is to strengthen the structure using external prestressed carbon fiber reinforced polymer (CFRP) straps. In this system, layers of CFRP tape are wrapped around a beam to form a strap that acts like a discrete unbonded vertical prestressing tendon. Experiments were undertaken to investigate the influence of the strap spacing, the strap stiffness, the initial strap prestress level and/or any preexisting damage on the strengthened behavior, and mode of failure. An unstrengthened control beam was tested and failed in shear. In contrast, all of the strengthened beams showed a significant increase in their ultimate load capacity with several of the strengthened beams failing in flexure. A number of different failure modes were noted and initial guidelines on the design parameters that influence the propensity for a particular failure mode were developed.
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Acknowledgments
The writers would like to thank the Swiss Federal Laboratories for Materials Testing and Research (EMPA) for their most helpful support and guidance.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 11 • Issue 4 • August 2007
Pages: 375 - 383
Copyright
© 2007 ASCE.
History
Received: May 10, 2006
Accepted: Jul 19, 2006
Published online: Aug 1, 2007
Published in print: Aug 2007
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