Abstract:

To definitude the effect of FRP-bolt strengthening technology, and also on the basis of the destructive characteristics of aging RC beam bridges, interior contrast tests of FRP surface adhesion and FRP-bolt hybrid boding were conducted to examine the strengthening effect on RC beams in shear. The results of the EB-FRP and HB-FRP were compared. In particular, the influence of pre-cracking level and FRP strip spacing on RC beams strengthened in shear with the hybrid bonding of FRP were assessed. The experimental results show that the hybrid bonding of FRP is a more reliable strengthening technique and which can improve the shear capacity of beams. The new mechanical fastening technique does not rely on bearings to transmit the interfacial shear, but instead increases the interfacial bond by resisting the separation of the FRP laminate from the concrete substrate by the bolt pretension. This study helps to direct the design and the construction of the HB-FRP.

Key words: fiber reinforced polymer (FRP), screw bolt, hybrid methods, strengthening, shear capacity