Numerical Evaluation of Reinforced Concrete Beams Retrofitted Using Near-Surface Mounted Fiber Reinforced Polymer
This study aims to evaluate the flexural performance of strengthened reinforced concrete beams using the Near-Surface Mounted Fiber Reinforced Polymer (NSM FRP) system through numerical and analytical approaches. Four beam specimens were analyzed, consisting of one control beam without strengthening and three beams with different NSM FRP configurations, namely CFRP 1D10, CFRP 2D7, and CFRP 3D6. Numerical simulations were conducted using LS-DYNA software under four-point bending loading, while validation was carried out through cross-sectional analysis based on analytical methods. The results indicate that implementing NSM FRP significantly enhances the flexural strength and ductility of the beams, while also influencing their failure patterns. Beams strengthened with multiple small-diameter FRP bars exhibited better performance due to more uniform stress distribution, provided that adequate spacing was maintained to prevent overlapping tensile stresses.