Shear Transfer Mechanism of Concrete Strengthened with External CFRP Strips
Publication: Journal of Composites for Construction
Volume 21, Issue 2
Abstract
Concrete with reinforcing steel bars across a shear plane was strengthened using carbon fiber–reinforced polymer (CFRP) strips externally bonded to resist shear transfer. Specimens were designed and tested to give insight on shear transfer based on a component model. In this model, five components, i.e., the friction, aggregate interlock, adhesion, shear dilation, and dowel action, contributed to the overall shear resistance. Results indicated that the ultimate shear transfer capacities improved by 6 to 50% for specimens with steel reinforcement ratios varying from 0.46 to 1.20% and CFRP reinforcement ratios varying from 0.224 to 0.298%. The mechanism of shear resistance increase was due to the additional clamping force provided by CFRP strips, which led to a significant increase in the shear component of the adhesion. A best-fitting expression was presented to predict the ultimate shear transfer capacities of CFRP-strengthened concrete with satisfactory accuracy by comparing the calculated results with test data in this study and in literature. A general concept of equivalent reinforcement ratio was proposed to clarify the limitation of strengthening effect for shear transfer.
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Acknowledgments
The authors would like to extend their sincere gratitude to the National Science Foundation of China for the financial support (Grant No. 51578399).
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Information & Authors
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Published In
Journal of Composites for Construction
Volume 21 • Issue 2 • April 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Feb 4, 2016
Accepted: Jul 27, 2016
Published online: Aug 16, 2016
Discussion open until: Jan 16, 2017
Published in print: Apr 1, 2017
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