A Study On The Cracking Behavior Of Gfrp Reinforced Concrete Beams

During the last years, the use of GFRP bars as internal reinforcement in concrete structures, gained more and more attention, as a good and sometimes a better alternative to steel reinforcement especially in corrosive situations and in aggressive environment. GFRP bars, which are fibers with high resistance immersed in a polymer resin matrix, with high tensile resistance and also resistant to corrosion, give better results regarding the tensile strength of the concrete structures, but due to their low elastic modulus and the poor bond with the concrete, as compared to steel reinforcing bars, the use of GFRP results in greater deflections and larger crack width under service loads.This paper aims to investigate the cracking behavior of GFRP reinforced members and their design based on SLS method as it represents the most problematic one, focusing on the cracking of GFRP reinforced beams. The work presented here includes the results from 4 GFRP beams tested. During the loading the cracks visible to the naked eye were marked with a pencil and photographed, creating a complete framework of the crack development in the beams until their destruction. The data related to the size of the cracks, the reductions, and the curvature of the beam as a function of loading, are recorded by the MGC device and elaborated in the form of graphs. Experimental data were analyzed and integrated in appropriate charts and are compared to predicted calculations based on American Code ACI 440.1R -06