Flexural Strengthening of Reinforced Concrete Beams with Variable Compressive Strength Using Near-Surface Mounted Carbon-Fiber-Reinforced Polymer Strips [NSM-CFRP]

An experimental and analytical investigation was conducted on reinforced concrete (RC) beams strengthened in flexure using the near-surface mounted carbon-fiber-reinforced polymers (NSM-CFRPs) technique. A total of 11 full-scale RC rectangular were cast tested under a monotonic three-point bending test, up to failure. The main test variables adopted this study compressive strength (high, medium, low), number CFRP strips, strip length. results indicated that use NSM-CFRPs strips different configurations efficiently increased load-carrying capacity beams, which all these exhibited higher moment resistance than corresponding un-strengthened beam. Results also showed strengthening schemes successful increasing flexural specimens tested. Such increases ranged between 10.36% 52.28%. Notably, significant improvement ultimate load ratio observed with having low 17-MPa, then followed by medium (32-MPa), finally high (47-MPa). NSM technique reduced occurrence possibility de-bonding failure mode. Furthermore, compared theoretical predictions ACI 440.2R17 guidelines good agreement results.