Near-Surface-Mounted CFRP for Strengthening Concavely Curved Soffit RC Beams: Experimental and Analytical Investigation
Publication: Journal of Composites for Construction
Volume 26, Issue 5
Abstract
Near-surface-mounted (NSM) carbon fiber–reinforced polymers (CFRPs) have emerged as a promising strengthening technique to improve the flexural performance of reinforced-concrete (RC) structures. Although these systems have been investigated extensively for flat soffit RC beams, their performance when applied to concavely curved soffit members requires investigation. This paper presents the results of an experimental program conducted to investigate the behavior of concavely curved soffit RC beams strengthened in flexure with NSM CFRP rods. Twenty RC beams were designed, fabricated, and statically tested, including 15 beams that contained curved soffits with varying degrees of curvature ranging between 5 to 20 mm/m. The remaining five beams were flat soffit and were used as control beams. The ultimate capacity, failure mode, flexural stiffness, ductility, and level of FRP strain prior to debonding of these beams are analyzed and discussed. This study identifies gaps in existing design guidelines and codes and presents recommendations for designers on NSM technology.
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Acknowledgments
The joint scholarship support provided to the first author by the Iraqi Ministry of Higher Education and Scientific Research and the Swinburne University of Technology is gratefully acknowledged. The authors wish to acknowledge the technical support provided by the staff of the Smart Structures Laboratory at Swinburne University of Technology. The support of BASF (Australia) for supplying all the FRP and epoxy material used is gratefully acknowledged.
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Published In
Journal of Composites for Construction
Volume 26 • Issue 5 • October 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Oct 9, 2021
Accepted: May 8, 2022
Published online: Jul 19, 2022
Published in print: Oct 1, 2022
Discussion open until: Dec 19, 2022
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