Static Cyclic Response of Masonry Walls Retrofitted with Fiber-Reinforced Polymers
Publication: Journal of Composites for Construction
Volume 11, Issue 1
Abstract
The behavior of seven one-half scale masonry specimens before and after retrofitting using fiber-reinforced polymer (FRP) is investigated. Four walls were built using one-half scale hollow clay masonry units and weak mortar to simulate walls built in central Europe in the mid-20th century. Three walls were first tested as unreinforced masonry walls; then, the seismically damaged specimens were retrofitted using FRPs. The fourth wall was directly upgraded after construction using FRP. Each specimen was retrofitted on the entire surface of a single side. All the specimens were tested under constant gravity load and incrementally increasing in-plane loading cycles. The tested specimens had two effective moment/shear ratio, namely, 0.5 and 0.7. The key parameter was the amount of FRP axial rigidity, which is defined as the amount of FRP reinforcement ratio times its modulus. The single-side retrofitting/upgrading significantly improved the lateral strength, stiffness, and energy dissipation of the test specimens. The increase in the lateral strength was proportional to the amount of FRP axial rigidity. However, using high amount of FRP axial rigidity led to very brittle failure. Finally, simple existing analytical models estimated the ultimate lateral strengths of the test specimens reasonably well.
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Acknowledgments
The FRP provided by SIKA AG is gratefully acknowledged. The fabrication of the half-scale bricks by Morandi is acknowledged. Appreciation is also extended to Mr. Jorge Hegner, former graduate student at EPFL.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 11 • Issue 1 • February 2007
Pages: 50 - 61
Copyright
© 2007 ASCE.
History
Received: Sep 20, 2005
Accepted: Mar 2, 2006
Published online: Feb 1, 2007
Published in print: Feb 2007
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