External near-surface mounted steel wire wrapping for shear enhancement of reinforced concrete beams

Shear failure in reinforced concrete (RC) beams remains a critical safety concern due to the risk of sudden brittle collapse from insufficient shear reinforcement. While conventional methods, including fiber-reinforced polymer systems, are widely used, near-surface mounted (NSM) high-strength steel wires have recently emerged as a promising alternative. This study investigates the shear performance of RC beams strengthened with NSM steel wires using various inclinations (45°, 60°, 90°) and innovative external NSM wrapping configurations, including U-wrapped, full-wrapped vertical, full-wrapped inclined, and cross-patterned arrangements. Experimental results demonstrated that full cross-pattern external wrapping with four NSM steel strips at 45° nearly restored the ultimate shear capacity of deficient beams, increasing ultimate load by 91%, stiffness by 152%, and energy absorption by 436% compared to unstrengthened beams. Nonlinear finite element analyses (NLFEA) showed close agreement with experiments (2–8% discrepancy), confirming the reliability of the numerical modeling. These findings highlight the effectiveness of external NSM steel wire wrapping for shear-deficient RC beams and provide a solid basis for developing practical design models to enhance shear resistance.