Retrofitting of Severely Shear-Damaged Concrete T-Beams Using Externally Bonded Composites and Mechanical End Anchorage
Publication: Journal of Composites for Construction
Volume 16, Issue 6
Abstract
The effectiveness of using an externally bonded carbon-fiber-reinforced polymer (EB-CFRP) system with mechanical end anchorage to retrofit severely shear-damaged reinforced concrete (RC) beams is examined in this paper. A total of 14 tests were performed on eight RC beams with a -shaped section and low compressive strength. To represent a severe shear-damage condition, five beams were tested to failure, retrofitted, then retested to failure for a second time. Test parameters included the number of EB-CFRP layers and type of end anchorage system. The results demonstrated that retrofitting of severely shear-damaged RC -beams with EB-CFRP composites and proper mechanical end anchorage can fully restore the original shear capacity of the beams. The use of a sandwich composite panel in combination with a threaded anchor rod inserted through the entire web width (thru-bolt) as an end anchorage system was more effective than using the panel with side powder-actuated fasteners. Increasing the number of EB-CFRP layers did not result in additional gain in shear capacity. The accuracy and validity of four different international guidelines/standards were examined by comparing their predictions with the experimental results.
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Acknowledgments
The authors wish to express their gratitude to the UAE University and Emirates Foundation grant no. 2009/052 for financing this research work. The authors would like to thank Mr. Abdelrahman Al-Sallamin, Eng. Tarek Salah, and Mr. Faisel Abdel-Wahab for their assistance throughout testing.
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© 2012 American Society of Civil Engineers.
History
Received: Nov 28, 2011
Accepted: Apr 3, 2012
Published online: Apr 10, 2012
Published in print: Dec 1, 2012
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