The flexural behavior of RC beams strengthened by near-surface mounted steel or FRP bars is investigated experimentally and numerically

Ahmed Ali

doi:10.66632/eei-2026-26

Authors

Ahmed Ali Department of Civil Engineering, Higher Technological Institute, 10th of Ramadan City, Egypt Author
- Conceptualization
- Formal Analysis
- Funding Acquisition
- Methodology
- Software
- Validation
- Visualization
- Writing – Review & Editing

DOI:

https://doi.org/10.66632/eei-2026-26

Keywords:

Near-surface mounted, CFRP, GFRP, Strengthening, Failure modes, Crack patterns

Abstract

The near-surface mounted (NSM) method, which involves attaching strips or rods in grooves made inside the concrete cover with an adhesive, has been shown to be efficient in strengthening because of the bonding area it offers and its capacity to delaying debonding. The flexural behavior of reinforced concrete (RC) beams strengthened with steel and fiber reinforced polymer FRP bars was experimentally investigated. Four RC beams were casted and tested under four points loads. The effect of bars types was studied represented in steel, glass-FRP (GFRP), and carbon-FRP (CFRP). The load capacity, deflection, failure modes, crack patterns, stiffness, toughness, and ductility of the tested RC beams were collected and analyzed. Enhancing for beam strengthened with NSM steel, GFRP, and CFRP bar in carrying load with 60.6, 72.6, and 81.1% and in yielding loads 78.1, 45.3, and 82.8% respectively over the control beam (CB)..

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