Behavior of Square Slender RC Columns Strengthened with Longitudinal FRP Sheets Subjected to Eccentric Loading
Publication: Journal of Composites for Construction
Volume 25, Issue 2
Abstract
In this study, the grooving method was employed to strengthen reinforced concrete (RC) columns with longitudinal fiber-reinforced polymer (FRP) sheets, and the performance of columns was investigated under both concentric and eccentric loadings. Furthermore, the effects of longitudinal FRP sheets and the grooving method on the ductility of strengthened concrete columns were studied. For this study, 12 slender square concrete columns with a slenderness ratio of 25 were subjected to eccentric loading with various eccentricity-to-cross section ratios (e/h) equal to 0, 0.24, 0.48, and 0.72 (i.e., eccentricities of 0, 30, 60, and 90 mm). Externally bonded reinforcement (EBR) and externally bonded reinforcement on grooves (EBROG) methods were utilized for FRP strengthening of the specimens. The results demonstrated that for the eccentricity ratios of 0, 0.24, 0.48, and 0.72, the load-carrying capacity of the columns strengthened with the EBROG method increased by 10.6%, 19.6%, 68.8%, and 99.3%, respectively, compared to those of the nonstrengthened columns. Particle image velocimetry (PIV) analyses demonstrated that under all the loading conditions investigated, the grooving method effectively improved the column performance, including load-bearing and flexural capacities. Such analysis also revealed that the application of longitudinal FRP sheets led to significant enhancements in the ductility of the columns tested.
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Acknowledgments
The authors would like to express their special thanks to Dr. A. Akhlaghi and Eng. E. Barati from the Structural Laboratory at Isfahan University of Technology (IUT) for their valuable guidance throughout this study. Furthermore, the authors greatly appreciate Foolad Kavir Co. and its manager Mr. Khorvash for providing the steel bars used in the column specimens.
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Published In
Journal of Composites for Construction
Volume 25 • Issue 2 • April 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Feb 28, 2020
Accepted: Nov 30, 2020
Published online: Jan 22, 2021
Published in print: Apr 1, 2021
Discussion open until: Jun 22, 2021
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