Investigating the shear flexural behavior of NSM FRP-strengthened RC beams by experimentation and numerical analysis

Abd Al-Kader A. Al Sayed; Ahmed Ali; Mohammed Yahya M. Al-Fasih

doi:10.66632/eei-2026-30

Authors

Abd Al-Kader A. Al Sayed Department of Civil Engineering, College of Engineering and Information Technology, Onaizah Colleges, Qassim, Saudi Arabia Author dr.ahmeda.kader@oc.edu.sa
Ahmed Ali Department of Civil Engineering, Higher Technological Institute, 10th of Ramadan City, Egypt Author Ahmed.ali@hti.edu.eg
Mohammed Yahya M. Al-Fasih Department of Civil Engineering, College of Engineering and Information Technology, Onaizah Colleges, Qassim, Saudi Arabia Author M.alfasih@oc.edu.sa

https://doi.org/10.66632/eei-2026-30

Keywords:

Strengthening, NSM, CFRP, Debonding, Concrete cover separation, End Anchorage, Finite element modeling, Fracture energy

In recent years, near-surface-mounted (NSM) FRP has become a strong alternative to the externally bonded (EB) technique. Compared to the EB approach, the NSM tech-nology is less susceptible to external damage sources and improves the bond between the FRP reinforcement and the surrounding concrete. However, one of the most com-mon reasons why RC beams reinforced with NSM technology fail is debonding via concrete cover separation (CCS), which begins and ends at low strain levels in the NSM reinforcement. Scientists therefore put a lot of effort into figuring out how to de-lay or prevent this kind of failure. In this investigation, two different bar configura-tions with straight and bent ends were used. The purpose of the bent end is to delay or prevent the CCS failure. A numerical analysis utilizing non-linear finite element mod-eling (FEM) was performed in ANSYS® to confirm the experimental results. Overall, there was good agreement between the numerical results and the corresponding ex-perimental data at each loading level.

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