Experimental Research on Damping and Bonding Properties of Concrete Reinforced with GFRP Bars

FRP composites possess superior properties compared to conventional steel material, such as light weight, high strength, high resistance to corrosion and ease of handling. In this paper, the experimental investigation on damping capacity of GFRP reinforced concrete materials and its members with different reinforcement ratio, stirrup spacing, and size effect was carried out by the method of 3-point bending beam damping measurement and cantilever beam free vibration respectively. The effects on bonding stress of concrete reinforced with GFRP bars with different embedded depth, cover thickness, diameter and surface form of bar were also studied by Pull-out Test. The experimental results show that the damping reinforced effect achieved best with about 0.9% reinforcement ratio. The smaller stirrup spacing had positive effect on damping capacity but size of the specimen had negligible influence on damping; Then bonding-slip relationships were gotten and compared with three bold-slip models, the results indicate that the smaller diameter, lager cover thickness and increasing surface roughness are helpful to get high average bond stress.