In-Plane Seismic Strengthening of Nonductile Reinforced Concrete Shear Walls Using Externally Bonded CFRP Sheets
Publication: Journal of Composites for Construction
Volume 20, Issue 6
Abstract
This study evaluated the effectiveness of using externally bonded carbon fiber–reinforced polymer (CFRP) sheets to enhance the seismic performance of nonductile reinforced concrete shear wall specimens representative of low aspect ratio walls. The specimens were designed to replicate structural deficiencies typically found in older concrete structures constructed during the 1960s and 1970s. The nonductile reinforcement details included insufficient shear reinforcement, lack of boundary elements, and low concrete compressive strength. The specimens were repaired or strengthened using vertical and horizontal CFRP sheets and then cyclically tested to simulate seismic loading. A tube anchor system was used to transfer the tensile force carried by the CFRP sheet to the foundation of the specimens. Experimental results showed that the CFRP retrofitting system was able to restore the original strength and initial stiffness of severely damaged specimens and significantly increase the flexural strength, ductility, and energy dissipation capacity in strengthening applications.
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Acknowledgments
The financial support provided by the Natural Sciences Engineering Research Council and the Canadian Seismic Research Network (CSRN) is gratefully acknowledged. The CFRP materials were provided by Fyfe Co., LLC. The technical assistance provided by Fibrwrap Construction and Hilti Canada in this research is also acknowledged.
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Information & Authors
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Published In
Journal of Composites for Construction
Volume 20 • Issue 6 • December 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Oct 24, 2015
Accepted: Feb 16, 2016
Published online: May 9, 2016
Discussion open until: Oct 9, 2016
Published in print: Dec 1, 2016
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