Behavior of Various Anchorage Systems Used for Shear Strengthening of Concrete Structures with Externally Bonded FRP Sheets
Publication: Journal of Bridge Engineering
Volume 18, Issue 9
Abstract
Efforts to prevent the debonding failure mode of externally bonded fiber-reinforced polymer (FRP) strengthening systems have led to the investigation of many different kinds of anchorage systems. An effective anchorage system allows externally bonded FRP reinforcements to continue carrying load, even after debonding occurs. In this study, an experimental program was performed on six full-scale RC T-beams strengthened in shear using externally bonded carbon FRP sheets with three different anchorage systems, the so-called (1) discontinuous mechanical anchorage (DMA) system, (2) sandwich discontinuous mechanical anchorage (SDMA) system, and (3) additional horizontal strips (HS) system. The experimental results showed that the SDMA system performed best, followed by the DMA and HS systems. The RC T-beams strengthened with the SDMA system showed a 59–91% increase in shear strength, altering the failure mode from FRP debonding to FRP rupture. In addition, the shear contribution of internal transverse steel reinforcement (stirrups) changes, depending on the types of anchorage system.
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Acknowledgments
The financial support from the National Cooperative Highway Research Program (NCHRP) and the National University Transportation Center (NUTC) at the Missouri University of Science and Technology is gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 18 • Issue 9 • September 2013
Pages: 837 - 847
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Dec 28, 2011
Accepted: Jun 5, 2012
Published online: Jul 21, 2012
Published in print: Sep 1, 2013
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