Experimental Investigation on Flexural Behavior of Concrete Beams reinforced with GFRP Bar with Working Cracks

Abstract

Based on 12 GFRP reinforced concrete beams with initial cracks, the bearing capacity, failure mode and crack propagation of strengthened concrete beams which considering the factors such as the initial crack and concrete grade was investigated through four-point bending test. The results showed that the initial crack have no obvious influence on the failure mode of GFRP reinforced concrete beam. Regardless of initial crack considerations, the strengthened concrete beams has damage with crush of compression zone concrete as load increasing. On the same concrete strength grade, the mid-span deflection of GFRP reinforced concrete beam with initial cracks is slightly larger than the values of GFRP concrete beam which regardless of the initial cracks. Concrete grade has an effect on stiffness of GFRP reinforced concrete beam with initial cracks. With the increase of concrete grade, the down-trend of bearing capacity caused by initial cracks has slowed down.