Single Crack–Based Model for FRP Shear-Strengthened RC Beams
Publication: Journal of Composites for Construction
Volume 23, Issue 4
Abstract
In this study, a single crack–based model is proposed for predicting the contribution of fiber-reinforced polymer (FRP) reinforcement to the shear resistance of FRP shear-strengthened reinforced concrete beams. This critical single shear crack has been found to be dominant within the shear span of many RC beams strengthened with externally bonded (EB) FRP and RC beams with near-surface mounted (NSM) FRP at large spacings. In this study, the single shear crack was assumed to occur along the principal stress trajectory (PST), along which concrete is subject to principal tensile stresses. A bilinear bond-slip model was adopted for the cohesive stresses due to FRP reinforcement and steel stirrups, and an exponential model was chosen for the cohesive stress due to aggregates. The shear crack configuration (e.g., crack width and length) was an implicit function of the external loading and cohesive stresses, which was obtained by numerical iterations. To verify the precision of the proposed model, several viable experimental studies on FRP shear-strengthened RC beams using either EB or NSM techniques were selected for comparisons. The model predicted shear crack trajectory, FRP strain distribution, stirrup strain distribution, and FRP contribution to the overall shear resistance well.
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Acknowledgments
The work of the first author was supported by the Natural Science Foundation of China under Grant No. 51808344 and the Natural Science Foundation of Guangdong Province under Grant No. 2018A030310535.
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Published In
Journal of Composites for Construction
Volume 23 • Issue 4 • August 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Apr 27, 2018
Accepted: Jan 8, 2019
Published online: Jun 8, 2019
Published in print: Aug 1, 2019
Discussion open until: Nov 8, 2019
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