Lagged strain of laminates in RC beams strengthened with fiber-reinforced polymer

Abstract

Based on the theory of concrete structure, a new expression was derived for lagged strain of fiber-reinforced polymer (FRP) laminates in reinforced concrete (RC) beams strengthened with FRP. The influence of different preloaded states and nonlinear stress-strain relationship of compressed concrete were both taken into account in this approach. Then a simplified expression was given by ignoring tensile resistance of concrete. Comparison of analytical predictions with experimental results indicates satisfactory accuracy of the procedures. The errors are less than 8% and 10% respectively when the tensile resistance of concrete is or not considered. While the maximum error of existing procedures is up to 60%.

Keywords

reinforced concrete beam / bonded laminates strengthening / lagged strain / preloaded state

References

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