Experimental Investigation and Fracture Analysis of Debonding between Concrete and FRP Sheets
Publication: Journal of Engineering Mechanics
Volume 132, Issue 9
Abstract
The last few years have witnessed a wide use of externally bonded fiber reinforced polymer (FRP) sheets for strengthening existing reinforced and prestressed concrete structures. The success of this strengthening method relies on the effectiveness of the load-transfer between the concrete and the FRP. Understanding the stress transfer and the failure of the concrete–FRP interface is essential for assessing the structural performance of strengthened beams and for evaluating the strength gain. This paper describes an experimental investigation of the interfacial bond behavior between concrete and FRP. The strain distributions in concrete and FRP are determined using an optical technique known as digital image correlation. The results confirm that the debonding process can be described in terms of crack propagation through the interface between concrete and FRP. The data obtained from the analysis of digital images was used to determine the interfacial material behavior for the concrete–FRP interface (stress versus relative displacement response) and the fracture parameter (fracture energy). The instability in the test response at failure is shown to be the result of snapback, which corresponds with the elastic unloading of the FRP as the load carrying ability of the interface decreases with increasing slip.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 132 • Issue 9 • September 2006
Pages: 914 - 923
Copyright
© 2006 ASCE.
History
Received: Mar 16, 2004
Accepted: Jan 11, 2005
Published online: Sep 1, 2006
Published in print: Sep 2006
Notes
Note. Associate Editor: Eric N. Landis
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