Effect of different material and construction details on the bond behaviour of NSM FRP bars in concrete

Flexural behavior of RC beams strengthened by NSM GFRP Bars having different end conditions

“…The straight and inclined grooves were made during casting of the beams using square wood strips placed inside the molds of the beams. The installation of straight NSM bar was discussed elsewhere [33][34][35]. For the bars with bent ends, the inclined grooves were filled by epoxy and then the NSM bars were applied as in case of straight NSM bars.…”

“…Sharaky et al [1,[33][34][35] studied the bond and flexural behavior of NSM strengthened elements with different material types, epoxy properties, bar size and number of NSM bars using two different techniques to delay or prevent the concrete cover separation or end slip. In the first technique mechanical end anchor was used.…”

Experimental and analytical investigation into the flexural performance of RC beams with partially and fully bonded NSM FRP bars/strips

“…Compared to EB systems, the test data available on bonding between NSM FRP reinforcement and concrete is still limited. Several parameters affect this bonding, such as bar properties (material, surface treatment, shape and size), groove geometry (shape and size), adhesive (type and properties), concrete properties and environmental effects [2][3][4][5][6].…”

“…Several experimental investigations have been performed to assess the load carrying capacity of the NSM technique [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. These have shown that the technique is greatly affected by bond behavior mainly depending on FRP properties, groove surface and dimensions, adhesive and concrete properties and the position of the FRP reinforcement.…”

A Parametric Study on the Flexural Strengthening of Reinforced Concrete Beams with Near Surface Mounted FRP Bars

“…Hence, a great number of researchers have studied the effective factors affecting the efficiency of application FRP with different techniques like NSM and EBR via various methods and solutions. Experimental studies of Al-Mahmoud et al [14], Barros and Fortes [15] Bilotta et al [6,7,9], Grace et al [2], Lee et al [16], Lu et al [17], Novidis et al [13], Rizzo, and De Lorenzis [18], Sharaky et al [11,[19][20][21], Tang et al [22], Wang et al [23], Wu et al [24] and numerical analyses of Bianco et al [25,26], Coelho et al [27], Hawileh [28], Kara et al [29], Kaveh et al [30], Seo et al [31], Sharaky et al [20], Teng et al [32], Zhang et al [33] are some of the most recent and pioneer studies in the field of strengthening existing structures with FRP according to the near surface mounted (NSM). Despite the fact that innumerable recent studies devoted at appraising the potentialities of strengthening existing structures with FRP, nevertheless limited design guidelines are currently available for either the externally bonded reinforcement or near surface mounted strengthening technique.…”