Flexural Strengthening of Columns with CFRP Composites and Stainless Steel: Cyclic Behavior
Publication: Journal of Structural Engineering
Volume 142, Issue 2
Abstract
This study presents the testing, completion, and analysis of different external strengthening systems applied to rectangular reinforced concrete columns with rounded corners. The experimental study included confinement strengthening with carbon-fiber-reinforced polymer (CFRP) sheets, longitudinal strengthening with CFRP laminates and confining CFRP jacket, longitudinal strengthening with stainless steel bars and confining CFRP jacket, tested column until reinforcing steel failure, repair and CFRP confining jacket, and longitudinal strengthening with stainless steel bars. The analysis of the experimental results included lateral load-displacement relationship, energy dissipation, ductility, and curvature damage assessment classifications. It was concluded that the use of external longitudinal strengthening combined with CFRP confinement is effective for enhancing performance and is viable in terms of execution. The load capacity increase due to strengthening reached 36–46% with good ductile behavior (failure was reached at 4.4% drift ratio). Despite some differences between CFRP laminates and stainless steel, all columns presented moderate degrees of damage between 1 and 2% drift ratio and minor damage degree until 1% drift ratio.
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Acknowledgments
The authors wish to express their appreciation to engineer Tiago Almeida, Professor Rui Marreiros, and Mr. Jorge SilvØrio for their help in the preparation and completion of the tests and to engineer Vítor Silva for his help in the execution of the tests on the various materials samples.
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Published In
Journal of Structural Engineering
Volume 142 • Issue 2 • February 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Jan 12, 2015
Accepted: Jul 14, 2015
Published online: Sep 21, 2015
Published in print: Feb 1, 2016
Discussion open until: Feb 21, 2016
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