Refinement of a Design-Oriented Stress–Strain Model for FRP-Confined Concrete
Publication: Journal of Composites for Construction
Volume 13, Issue 4
Abstract
This paper presents the results of a recent study conducted to refine the design-oriented stress–strain model originally proposed by Lam and Teng for fiber-reinforced polymer (FRP)-confined concrete under axial compression. More accurate expressions for the ultimate axial strain and the compressive strength are proposed for use in this model. These new expressions are based on results from recent tests conducted by the writers’ group under well-defined conditions and on results from a parametric study using an accurate analysis-oriented stress–strain model for FRP-confined concrete. They allow the effects of confinement stiffness and the jacket strain capacity to be separately reflected and accounts for the effect of confinement stiffness explicitly instead of having it reflected only through the confinement ratio. The new expressions can be easily incorporated into Lam and Teng’s model for more accurate predictions. Based on these new expressions, two modified versions of Lam and Teng’s model are presented. The first version involves only the updating of the ultimate axial strain and compressive strength equations. The second version caters to stress–strain curves with a descending branch, which is not covered by the original model.
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Acknowledgments
The writers are grateful for the financial support received from the Research Grants Council of the Hong Kong SAR (Project No: PolyU 5059/02E) and The Hong Kong Polytechnic University (Project Codes: RG88 and BBZH).
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 13 • Issue 4 • August 2009
Pages: 269 - 278
Copyright
© 2009 ASCE.
History
Received: Sep 2, 2008
Accepted: Jan 19, 2009
Published online: Jul 15, 2009
Published in print: Aug 2009
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