Flexural Behavior of Stone Slabs Reinforced with Prestressed NSM CFRP Bars
Publication: Journal of Composites for Construction
Volume 18, Issue 4
Abstract
A technique for reinforcing stone slabs with prestressed near-surface mounted (NSM) carbon fiber–reinforced polymer (CFRP) bars is proposed and investigated in this research. Six stone slabs were tested under monotonic loading. Among these slabs, one served as a control slab and was not reinforced, and two were reinforced with one or two NSM CFRP bars, and each bar was prestressed to 30% of the bar’s ultimate strength. The remaining three were reinforced with three NSM CFRP bars that had been prestressed to 0, 15, or 30% of the bar’s ultimate strength. The test results indicate that reinforcement with either prestressed or nonprestressed NSM CFRP bars shifted the failure mode of the stone slabs from abrupt fracture to a more ductile flexural failure. A remarkable improvement in the flexural response was obtained when the stone slabs were reinforced with prestressed NSM CFRP bars. In addition to exhibiting a higher cracking load, the stone slabs that had been reinforced with prestressed NSM CFRP bars exhibited cracks with a smaller width, and the strength utilization of the CFRP reinforcement was much higher compared to that of the nonprestressed reinforced slabs. An analytical model was developed based on a sectional analysis method to predict the flexural response of stone slabs reinforced with prestressed NSM CFRP bars. The predicted values show good agreement with the experimental results.
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Acknowledgments
This research was funded as a major project for university–industry cooperation by Fujian Province, China (grant No. 2011Y4008). The authors would like to thank all of the technicians at the structural laboratory at Huaqiao University.
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Published In
Journal of Composites for Construction
Volume 18 • Issue 4 • August 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Aug 12, 2013
Accepted: Nov 19, 2013
Published online: Jan 24, 2014
Discussion open until: Jun 24, 2014
Published in print: Aug 1, 2014
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