Behavior of RC Slab-Column Connections Strengthened with External CFRP Sheets and Subjected to Eccentric Loading
Publication: Journal of Composites for Construction
Volume 17, Issue 4
Abstract
Strengthening of both aging and modern infrastructure has become necessary as a result of increased load demand and/or to restore the capacity of a member. For example, flat slabs (commonly utilized in parking garages) are subjected to an aggressive environment and increased traffic loads and additionally require strengthening and/or repair. Fiber-reinforced polymer (FRP) sheets and laminates externally bonded to concrete slabs around the slab-column joint are widely used to enhance the strength of flat slabs. Slab-column connections are most often subjected to eccentric loading; however, most reported studies have focused on retrofitted slab-column connections subjected to concentric loads. This paper aims to fill this knowledge gap and experimentally investigate the effect of eccentric loading on the behavior of slab-column connections retrofitted by externally bonded carbon fiber-reinforced polymer (CFRP) sheets. Six full-scale () interior slab-column connections subjected to eccentric loading were constructed and tested to failure. Three control test specimens were subjected to applied loads with different eccentricities. The remaining three test specimens were externally strengthened with different configurations of carbon FRP sheets before being subjected to eccentric loading. The test results are presented as comparisons of the load-deflection and load-strain behavior. Eccentric loading reduces the ultimate load capacity and ductility of slab-column connections. The increase of the ultimate strength of carbon FRP-strengthened slab-column connections decreases with the increase of applied load eccentricity.
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Acknowledgments
The writers express their gratitude and sincere appreciation for the financial support received from the Natural Science and Engineering Research Council of Canada (NSERC) through the Discovery and Canada Research Chair programs. The equipment provided by a Canada Foundation for Innovation (CFI) grant is greatly appreciated. The assistance provided by the technical staff of the Structural Laboratory in the Department of Civil and Environmental Engineering at the University of Windsor is also gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 17 • Issue 4 • August 2013
Pages: 488 - 496
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Jun 28, 2012
Accepted: Oct 24, 2012
Published online: Oct 26, 2012
Discussion open until: Mar 26, 2013
Published in print: Aug 1, 2013
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