Debonding Strength of Steel Beams Strengthened with CFRP Plates
Publication: Journal of Composites for Construction
Volume 10, Issue 1
Abstract
This paper addresses the debonding strength of partial-length, adhesively bonded carbon fiber-reinforced polymer (CFRP) plates that are used to strengthen steel beams. Bonded CFRP plates tend to debond under static and fatigue loadings because of the very high stress field at the plate end. Such failures limit the application of CFRP plates. Static and fatigue tests show that the stress intensity factor governs the debonding strength. The steel/adhesive corner was the locus of debond initiation. The effects of the following parameters on stress intensity factors are discussed: plate thickness, plate modulus, bondline thickness, adhesive modulus, and adhesive spew-fillet angle. The stress intensity factors are calculated using the Betti’s law-based reciprocal work contour integral method (RWCIM). The parametric study results indicate that the stress intensity factors cannot be used to represent the severity of the corner as the adhesive spew-fillet angle (and singularity) changes. Therefore, the use of stress intensity factors as a failure criterion for the purpose of predicting debonding strength is limited to the same spew-fillet angle.
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Acknowledgments
The writers gratefully acknowledge the Thailand Research Fund for providing financial support. Thanks are due to Sika Thailand, Ltd., for providing composite materials and for fabrication of test specimens. The writers appreciate the suggestions received from Professor Eiichi Watanabe at Kyoto University, Japan.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 10 • Issue 1 • February 2006
Pages: 69 - 78
Copyright
© 2006 ASCE.
History
Received: Oct 20, 2004
Accepted: Jun 14, 2005
Published online: Feb 1, 2006
Published in print: Feb 2006
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