Modeling of debonding failure for RC beams strengthened in shear with NSM FRP reinforcement

Tests on reinforced concrete beams strengthened in shear using near surface mounted CFRP and steel bars

“…Examples include (1) adding external stirrups, (2) jacketing, (3) bonding external plates using epoxy or bolts and (4) bonding external FRP laminates. A recently proposed technique use NSM FRP bars or strips [1][2][3][4][5][6][7] to increase the area of transverse shear reinforcement. The bars or strips are embedded in grooves in the concrete and bonded using epoxy or cement grout.…”

Shear behaviour of RC beams strengthened with NSM and EB CFRP strips

“…Two different failure modes, such as debonding of the FRP bars and separation of the concrete cover of the steel longitudinal reinforcement, were identified by De Lorenzis and Nanni for beams strengthened in shear with NSM bars. Some debonding failure mode and bond slip relations were obtained from bond tests by other researchers (De Lorenzis and Nanni, 2002;Rizzo and De Lorenzis, 2009a). Recently, the effectiveness of the NSM technique for shear strengthening of concrete beams was tested by Barros and Dias (2006), but it is thought that the size of tested specimens was so small that the applicability to real structural members is insufficient.…”

Bau des Betongartens BUGA 2015 abgeschlossen

“…There are several methods for strengthening existing RC beams in shear, including RC jacketing, surface bonding of external steel plates using epoxy or steel bolts, or FRP bonding, either surface or near‐surface [5–9]. Various studies have been conducted to date and various strengthening methods have been introduced for shear‐deficient beams [9–16].…”