Abstract：The effects of two kinds of fiber materials strengthening reinforced concrete beams were analyzed based on comparing the cracking load and ultimate bearing capacity, crack distribution and failure mode, midspan deflection and deformation curve, through single point loading test on simple supported RC beams, and the beams reinforced by bonding different layers CFRP or GFRP ( 1 layer, 2 layers, 3 layers) on the tensile side. The results show that the strengthening of bonding CFRP is obviously superior to bonding GFRP in the improvements of the cracking load, ultimate bearing capacity. Thusly, the component strengthening of bonding CFRP has a higher safety margin, and the crack distribution pattern and failure mode of the beams are basically same. When bonding the same thickness, the high strength of CFRP is hardly utilized, the stiffness of the former is superior to the latter, and the ductility of the later is better.

Keyword：reinforced concrete beam;single point loading;strengthening bonded C/GFRP;