Abstract
An analytical model to predict the torsional moment capacity and the type of failure of thin walled tubular reinforced concrete elements strengthened with near surface mounted (NSM) carbon fiber reinforced polymer (CFRP) laminates is proposed. The model implements the thin walled space truss analogy, which forms the basis of current design codes, and evaluates the torsional capacity as a combination of the resistance offered by the transverse steel reinforcement and CFRP laminate reinforcement. The contribution of the steel reinforcement is limited by its yield strength and that of the CFRP laminates by an effective maximum strain. The model also implements the modified compressive field theory to evaluate the concrete compressive strut inclination.
The predictive performance of the developed model is compared against available models and assessed against experimental data obtained within the current research project and available in the literature. The model predicts the failure type and the ultimate torsional capacity with an error of 2.4% (with Co.V. of 5.1%) for current experimental research and 7.2% (with Co.V. of 8.6%) for other literature data.
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Acknowledgements
The first author would like to thank Foundation for Science and Technology, Portugal for funding the work through scholarship number SFRH/BD/129472/2017. The second author acknowledges the support provided by the project ICoSyTec (POCI-01–0145-FEDER-027990) financed by FCT and co-funded by FEDER through the Operational Competitiveness and Internationalization Programme (POCI).
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Gowda, C., Barros, J., Guadagnini, M. (2022). Analytical Model for Predicting the Torsional Capacity of Thin Walled Tubular RC Beams Strengthened with NSM CFRP Laminates. In: Ilki, A., Ispir, M., Inci, P. (eds) 10th International Conference on FRP Composites in Civil Engineering. CICE 2021. Lecture Notes in Civil Engineering, vol 198. Springer, Cham. https://doi.org/10.1007/978-3-030-88166-5_115
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