Experimental and theoretical investigation of continuous beams containing steel and fiber reinforced polymer bars

The application of the FRP bars as reinforcement, especially at structures exposed to aggressive environment, have become attractive because of their non-corrodible nature, high strength, light weight and ease of installation. In order to investigate the bending behavior and the redistribution of bending moments, the two-span FRP-reinforced continuous concrete beams reinforced with glass, carbon and basalt fiber reinforced polymers (FRP) combined with steel bars as hybrid longitudinal reinforcement, are presented in both experimental and analytical way in this study. The study shows that the amounts of FRP and steel reinforcement are very important in ensuring sufficient strength, ductility and rigidity of the beams, and the use of FRP bars with steel reinforcement enables the moment redistribution in hybrid FRP/Steel reinforced beams. It has been also observed that the use of steel reinforcement together with FRP bars, has a clear effect on the reduction of bending crack widths and displacements compared with FRP reinforced beams. Keywords: FRP bar, continuous beam, displacement, crack width, load capacity