RC Columns Strengthened with NSM-CFRP Strips and CFRP Wraps under Axial and Uniaxial Bending: Experimental Investigation and Capacity Models
Publication: Journal of Composites for Construction
Volume 25, Issue 2
Abstract
The efficiency of the use of near-surface mounted (NSM) carbon fiber-reinforced polymer (CFRP) strips confined with CFRP wraps to strengthen reinforced concrete (RC) columns will be experimentally and analytically investigated in this paper. A total of 15 specimens of RC columns strengthened with different numbers of NSM-CFRP strips (0, 4, and 8) and confined with different numbers of CFRP wraps (0, 2, and 4), will be prepared and tested under concentric and eccentric loading with different eccentricity ratios of 0, 0.25, 0.50, and 0.75, respectively. The axial load capacity, lateral deflection (Δ), axial deflection, and longitudinal and transverse strains will be measured. The effects of NSM-CFRP strips, the number of CFRP layers, and the eccentricity ratio on the capacity of the specimen will be investigated. The strengthened specimens showed a significant increase in load-carrying capacity and ductility over the control specimens. The increase in the load-carrying capacity of the confined specimens strengthened with strips in axial and uniaxial bending reached 49% and 95%, respectively, over the control specimen. It was concluded that strengthening RC columns with NSM-CFRP strips wrapped with CFRP composite sheets enhanced both the capacity and ductility consistently, for all applied eccentricity ratios. In addition, an analytical model will be developed to predict the strength of NSM-CFRP-strengthened RC columns and will be validated using the obtained experimental results.
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Acknowledgments
The support for the research presented in this paper was provided, in part, by Riad Sadek, Endowed Chair in Civil Engineering, and the Faculty Research Grants Program of the American University of Sharjah. The support for publication and dissemination of the results of this study was provided by the Open Access Program of the American University of Sharjah. All support is gratefully appreciated and acknowledged. The views and conclusions in this study, whether expressed or implied, are those of the authors and should not be interpreted as those of the supporting institution.
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Journal of Composites for Construction
Volume 25 • Issue 2 • April 2021
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Received: Apr 17, 2020
Accepted: Dec 2, 2020
Published online: Feb 3, 2021
Published in print: Apr 1, 2021
Discussion open until: Jul 3, 2021
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