Effect of Longitudinal Steel Ratio on Behavior of RC Beams Strengthened with FRP Composites: Experimental and FE Study
Publication: Journal of Composites for Construction
Volume 19, Issue 1
Abstract
This study experimentally and numerically investigates the effect of longitudinal steel ratio on the flexural performance of RC beams externally strengthened with fiber-reinforced polymer (FRP) composites. The experimental program consisted of testing 11 beams under four-point bending until failure. Each beam was duplicated to verify the repeatability of the results. Three beams were tested as control specimens; the remaining eight beams were externally strengthened in flexure with FRP composites. The primary experimentally studied parameters were longitudinal steel ratio and axial FRP stiffness. Three different steel ratios were examined. For the lowest steel ratio, four different FRP systems with six axial stiffness values were investigated. However, for the other two steel ratios, only one FRP system was studied. In addition to the experimental program, a numerical study utilizing nonlinear finite-element (FE) analysis was conducted. As a result of the numerical study, new FRP stiffness and reinforcement parameters were introduced in this research. These parameters were used in the categorization of failure modes of FRP-upgraded beams.
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Acknowledgments
The authors would like to extend their sincere appreciation to the Deanship of Scientific Research at King Saud University for its funding of this research through the research group project No. RGP-VPP-310. Thanks are also extended to the MMB Chair for Research and Studies in Strengthening and Rehabilitation of Structures, at the Department of Civil Engineering, King Saud University for providing technical support.
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Information & Authors
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Published In
Journal of Composites for Construction
Volume 19 • Issue 1 • February 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Nov 14, 2013
Accepted: Mar 11, 2014
Published online: May 7, 2014
Discussion open until: Oct 7, 2014
Published in print: Feb 1, 2015
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