Vol. 15 No. 02 (2025): Journal of Building Materials and Construction
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Tạp chí Vật liệu & Xây dựng - Bộ Xây dựng

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Model for determining the torsional resistance of reinforced concrete beams strengthened with externally bonded FRP sheets

Nguyễn Vĩnh Sáng , Nguyễn Anh Dũng , Nguyễn Ngọc Thắng

Keywords:

Torque
Torsional strength
Effective strain
Incline angle
Strut - and - tie model

Abstract

Reinforced concrete (RC) structural members, especially cantilever beams, bridge girders, curved beams, and eccentrically loaded beams, may be subjected to significant torsional loading. Although extensive research has been done on the strengthening of RC structures, fiber-reinforced polymer (FRP) laminates are commonly used to strengthen torsional structures. Therefore, some torsional design guidelines for RC structures strengthened with external FRP sheets were based on the equilibrium truss theory, such as fib Bulletin 90, NCHRP Report 655, and CNR-DT 200/2013. Two parameters that significantly influence the prediction of torsional capacity, namely the effective strain and the inclination angle of the main concrete crack, were also mentioned. However, there was no consensus among current standards and technical guidelines in determining the effective strain. In addition, the inclination angle was prescribed based on standards and technical guidelines for RC structures subjected to torsion. A strut-and-tie model proposed in this study was used to calculate this inclination angle. To evaluate the design methods in the standards and technical guidelines, 35 specimens strengthened with CFRP and GFRP sheets were collected in previous experimental studies. The calculation results showed that the calculation model, according to the standards and technical guidelines combined with the strut-and-tie method, was conservative in predicting the torsional resistance.

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How to Cite

Nguyễn Vĩnh Sáng, Nguyễn Anh Dũng, & Nguyễn Ngọc Thắng. (2025). Model for determining the torsional resistance of reinforced concrete beams strengthened with externally bonded FRP sheets. Tạp Chí Vật liệu & Xây dựng - Bộ Xây dựng, 15(02), Trang 21 – Trang 29. https://doi.org/10.54772/jomc.02.2025.794

References

  1. Chandan C. Gowda, J. A. O. B., Maurizio Guadagnini. (2019). Experimental study of torsional strengthening on thin walled tubular reinforced concrete structures using NSM-CFRP laminates. Composite Structures. 208(15): 585-599. doi:https://doi.org/10.1016/j.compstruct.2018.10.050
  2. Ghobarah, A., M. N. Ghorbel, and S. E. Chidiac. (2002). Upgrading torsional resistance of reinforced concrete beams using fiber-reinforced polymer. Journal of Composites for Construction. 6(4): 257–263. doi:https://doi.org/10.1061/(ASCE)1090-0268(2002)6:4(257)
  3. Mahshid Abdoli, D. M., Mohamadrza Eftekar, Alireza Saljoughian. (2024). Torsional strengthening of T-shaped RC members with FRP composites using EBROG method: Experimental investigation and analysis. Construction and Building Materials. 437: 136829. doi:https://doi.org/10.1016/j.conbuildmat.2024.136829
  4. Mahshid Abdoli, D. M., Mohammadreza Eftekhar. (2024). Aggregate interlock and effective strain of FRP-strengthened flanged RC members subjected to torsion: Experimental evaluation and analytical modeling. Construction and Building Materials. 437: 136865. doi:https://doi.org/10.1016/j.conbuildmat.2024.136865
  5. Fib-bulletin-90. (2019). Externally applied FRP reinforcement for concrete structures.Lausanne, Switzerland: CEB- FIP.
  6. Abdul-Hamid Zureick, B. R. E., Andrzej S. Nowak, Dennis R. Mertz, Thanasis C. Triantafillou. (2010). Recommended Guide Specification for the Design of Externally Bonded FRP Systems for Repair and Strengthening of Concrete Bridge Elements.Transportation Research Board.
  7. CNR-DT200/2013. (2013). Guide for the design and construction of externally bonded FRP Systems for Strengthening Existing Structures.CNR-DT200. Rome, Italy.
  8. ACI-318-19. (2019). Building code requirements for structural concrete and commentary American Concrete Institute, Farmington Hills, MI.
  9. 1992-1-1:2004, E. (2004). Design of Concrete Structures, Reinforced Concrete Standards; Reinforced Concrete Construction Standards. European Committee for Standardization.
  10. AASHTO-LRFD. (2014). Bridge Design Specifications.American Association of State Highway and Transportation Officials.
  11. 440.2R-17. (2017). Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures.American Concrete Institute (ACI).
  12. Meyyada Y. Alabdulhady, L. H. S., Christian Carloni. (2017). Torsional behavior of RC beams strengthened with PBO-FRCM composite – An experimental study. Engineering Structures. 136: 393–405. doi:https://doi.org/10.1016/j.engstruct.2017.01.044
  13. Shen, K., S. Wan, Y. Mo, and Z. Jiang. (2017). Theoretical analysis on full torsional behavior of RC beams strengthened with FRP materials. Compos. Struct. 183: 347–357. doi:https://doi.org/10.1016/j.compstruct.2017.03.084
  14. Meyyada Y. Alabdulhady, L. H. S. (2019). Analytical Study on the Torsional Behavior of Reinforced Concrete Beams Strengthened with FRCM Composite. Journal of Composites for Construction. 23: 2. doi:https://doi.org/10.1061/(ASCE)CC.1943-5614.0000927
  15. Yingbo Zhu, K. S., Alessandro Fascetti, Shui Wan, John C. Brigham, Jundong Fu. (2022). Torsional repair of damaged single-box multi-cell composite box-girder with corrugated steel webs using CFRP. Part II: Theoretical investigation. Composite Structures. 301: 116204. doi:https://doi.org/10.1016/j.compstruct.2022.116204
  16. Mahshid Abdoli, D. M., Mohamadreza Eftekhar. (2023). Ultimate torsional resistance and failure modes of FRP-strengthened reinforced concrete members: A nonlinear design model. Engineering Structures. 283: 115867. doi:https://doi.org/10.1016/j.engstruct.2023.115867
  17. Meyyada Y. Alabdulhady, L. H. S. (2019). Torsional strengthening of reinforced concrete beams with externally bonded composites: A state of the art review. Construction and Building Materials. 205: 148–163. doi:https://doi.org/10.1016/j.conbuildmat.2019.01.163
  18. Ahmed K. Soluit, M. A. M., Khaled M. El-Sayed, Soliman H. Shalaby. (2007). Torsional behavior of RC beams strengthened with fiber reinforced polymer sheets. Engineering Research Journal. 114: 102-119.
  19. Hiếu, N. T., Cường, L.T. (2018). Experimental study on the strengthening efficiency of reinforced concrete beams under torsion using CFRP sheets. Khoa học Kỹ thuật và Công nghệ. 60(3): 30-35.
  20. Chalioris, C. E. (2007). Tests and analysis of reinforced concrete beams under torsion retrofitted with FRP strips. Computational Methods and Experimental Measurements XIII 46: 633-642. doi:10.2495/CMEM070631
  21. Mehran Ameli, H. R. R., Peter F. Dux. (2007). Behavior of FRP strengthened reinforced concrete beams under torsion. J. Compos. Constr. 11(2): 192–200. doi:https://doi.org/10.1061/(ASCE)1090-0268(2007)11:2(192)
  22. Mohammad Reza Mohammadizadeh, M. J. F. (2008). Torsional Behaviour of High-Strength Concrete Beams Strengthened Using CFRP Sheets; an Experimental and Analytical Study. Civil Engineering. 16(4): 321-330.
  23. ACI-445.1R-12. (2012). Report on torsion in structural concrete (ACI 445.1R-12).American Concrete Institute, Farmington Hills, MI.