Seismic Repair and Strengthening of Lap Splices in RC Columns: Carbon Fiber–Reinforced Polymer versus Steel Confinement
Publication: Journal of Composites for Construction
Volume 15, Issue 5
Abstract
A design approach, developed specifically for seismic bond strengthening of the critical splice region of reinforced concrete columns or bridge piers, is presented and discussed. The approach is based on providing adequate concrete confinement within the splice zone for allowing the spliced bars to theoretically develop enough postelastic tension strains demanded by large earthquakes before experiencing splitting bond failure. The accuracy of the approach was validated experimentally by evaluating the seismic behavior of full-scale gravity load-designed (as-built) rectangular columns that were strengthened or repaired in accordance with the proposed approach. Three types of confinement were used and compared, namely, internal steel ties, external fiber polymer reinforced jackets, and a combination of both. The repaired/strengthened columns developed sizable postyield strains of the spliced bars, considerable increases in the lateral load and drift capacities, and much less concrete damage within the splice zone when compared with the as-built columns. As a further support of the adequacy of the design strengthening approach, the backbone lateral load-drift response of the strengthened columns showed a good agreement with the envelope response generated using nonlinear flexural analysis assuming perfect bond between the column reinforcement and concrete.
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Acknowledgments
This research was supported by the Lebanese National Council for Scientific Research (LNCSR). The writer is most grateful for this support and to the Faculty of Engineering and Architecture at the American University of Beirut (AUB) for providing the laboratory facilities.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 15 • Issue 5 • October 2011
Pages: 721 - 731
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Oct 3, 2010
Accepted: Feb 23, 2011
Published online: Feb 25, 2011
Published in print: Oct 1, 2011
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