Bond Behavior of Prestressed CFRP Strips-to-Concrete Joints Using the EBROG Method: Experimental and Analytical Evaluation
Publication: Journal of Composites for Construction
Volume 27, Issue 1
Abstract
Fiber-reinforced polymer (FRP) composites are widely employed as externally bonded reinforcement (EBR) systems for strengthening reinforced concrete members. More recently, a new technique, referred to as externally bonded reinforcement on grooves (EBROG), has been proposed, which is based on using a number of grooves throughout the concrete substrate to enhance the bond strength between the FRP composite and concrete. This study investigates the influence of groove depth on the resulting debonding process that can be observed in prestressed carbon FRP strips. To do so, prestressing force release tests were conducted on a series of EBR and EBROG FRP strips bonded to concrete specimens. Test results demonstrated that the fracture process leading to debonding of the EBROG specimens developed in a significantly different manner with respect to the case of EBR specimens. Specifically, fractures ran through deeper layers of concrete as the grooves became deeper. Numerical analyses are also proposed to scrutinize the actual bond–slip law characterizing both EBR and EBROG specimens. It was shown that a trilinear bond–slip law is appropriate for simulating the interface behavior in EBROG specimens.
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Acknowledgments
The authors sincerely thank the technical team at the Structural Engineering Research Laboratory of Empa, Switzerland. The financial support for performing the experiments and providing the materials by S&P Clever Reinforcement Company AG, Switzerland, is gratefully acknowledged. The first author was financed by mobility grants received from Iran’s Ministry of Science, Research and Technology (MSRT), Iran’s National Elites Foundation, Empa Structural Engineering Research Laboratory, and ZHAW (Swiss Leading House for research collaboration with partner institutions) for the visiting research period at Empa. Lastly, the second author would like to thank the Swiss National Science Foundation SNSF for its financial support during his stay at Empa (IZSEZO_202268).
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Published In
Journal of Composites for Construction
Volume 27 • Issue 1 • February 2023
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Dec 20, 2021
Accepted: Oct 5, 2022
Published online: Dec 6, 2022
Published in print: Feb 1, 2023
Discussion open until: May 6, 2023
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