Intermediate Crack Debonding in FRP-Strengthened RC Beams: FE Analysis and Strength Model
Publication: Journal of Composites for Construction
Volume 11, Issue 2
Abstract
Reinforced concrete (RC) beams strengthened in flexure with a bonded fiber-reinforced polymer (FRP) plate may fail by intermediate crack (IC) debonding, in which debonding initiates at a critical section in the high moment region and propagates to a plate end. This paper first presents a finite-element (FE) model based on the smeared crack approach for concrete for the numerical simulation of the IC debonding process. This finite-element model includes two novel features: (1) the interfacial behavior within the major flexural crack zone is differentiated from that outside this zone and (2) the effect of local slip concentrations near a flexural crack is captured using a dual local debonding criterion. The FE model is shown to be accurate through comparisons with the results of 42 beam tests. The paper also presents an accurate and simple strength model based on interfacial shear stress distributions from finite-element analyses. The new strength model is shown to be accurate through comparisons with the test results of 77 beams, including the 42 beams used in verifying the FE model, and is suitable for direct use in design.
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Acknowledgments
The writers are grateful for the financial support received from The Hong Kong Polytechnic University through its Area of Strategic Development (ASD) Scheme for the ASD in Urban Hazard Mitigation and the Natural Science Foundation of China (National Key Project No. UNSPECIFIED50238030).
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 11 • Issue 2 • April 2007
Pages: 161 - 174
Copyright
© 2007 ASCE.
History
Received: Jun 16, 2005
Accepted: Nov 16, 2005
Published online: Apr 1, 2007
Published in print: Apr 2007
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