Evaluation of Masonry Deep Beams Externally Strengthened with CFRP Sheets
Publication: Journal of Composites for Construction
Volume 14, Issue 2
Abstract
In this study, carbon fiber-reinforced polymer (CFRP) sheets were examined as a means to strengthening existing masonry walls allowing for efficient creation of doors, windows, and passage openings. The research reported here deals with eight masonry walls made with concrete blocks, subjected to three-point quasistatic loading. The parameters examined include the reinforcement configuration and their amount. While CFRP sheets were used as external reinforcement, companion studies were carried out with conventional steel rebars. Test results indicate an increase of 180% in shear strength of the reinforced walls as compared to reference unreinforced walls. Load-deflection relationships indicate that the combined plain masonry and CFRP laminate system possessed some nonlinear deformability. The use of CFRP laminates on the walls was found to have an influence on the mode of failure. Anchoring the CFRP laminates at both support regions helped in using a larger portion of the strength of the laminates. The reinforced walls exhibited diagonal shear cracks that developed at a much slower rate and were ultimately accompanied by the peeling off of the CFRP laminates.
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Acknowledgments
This study was conducted as part of the research leading to a M.Sc. degree for Z. Hao. It was funded in part by the Canadian Masonry Research Institute, the Network of Centres of Excellence on Intelligent Sensing for Innovative Structures, and the Natural Sciences and Engineering Research Council of Canada.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 14 • Issue 2 • April 2010
Pages: 152 - 161
Copyright
© 2010 ASCE.
History
Received: Jun 13, 2008
Accepted: Aug 10, 2009
Published online: Aug 12, 2009
Published in print: Apr 2010
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