Shear strength model of the reinforced concrete beams with embedded through-section strengthening bars

Abstract

In this study, finite element (FE) analysis is utilized to investigate the shear capacity of reinforced concrete (RC) beams strengthened with embedded through-section (ETS) bars. Effects of critical variables on the beam shear strength, including the compressive strength of concrete, stiffness ratio between ETS bars and steel stirrups, and use of ETS strengthening system alone, are parametrically investigated. A promising method based on the bond mechanism between ETS strengthening and concrete is then proposed for predicting the shear resistance forces of the strengthened beams. An expression for the maximum bond stress of the ETS bars to concrete is developed. This new expression eliminates the difficulty in the search and selection of appropriate bond parameters from adhesion tests. The results obtained from the FE models and analytical models are validated by comparison with those measured from the experiments. Consequently, the model proposed in this study demonstrates better performance and more accuracy for prediction of the beam shear-carrying capacity than those of existing models. The results obtained from this study can also serve researchers and engineers in selection of the proper shear strength models for design of ETS-strengthened RC beams.

Graphical abstract

Keywords

embedded through-section / strengthening / fiber-reinforced polymer / finite element / shear strength model / bond mechanism

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Acknowledgements

The authors acknowledge the financial support of Ho Chi Minh City Open University. The valuable comments regarding to the topic of this paper from Professor Tamon Ueda and Professor Boonchai Stitmannaithum are very grateful.

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