Comparative experimental investigation on the behaviour and strength of RC frames strengthened and retrofitted with GFRP composites

Abstract

This investigation is about the study of efficiency of GFRP (Glass Fibre Reinforced Polymer) composites in strengthening and retrofitting of seismically deficient reinforced concrete frames. Twelve numbers of single bay two storey two dimensional RC frames were cast and Six frames were tested for effectiveness of externally bonded GFRP composites to strengthen the RC frame, Six frames were loaded up to yield load and these yielded frames were wrapped with GFRP and tested for the effectiveness of retrofitting the yielded frames. A preliminary study on RC elements strengthened and retrofitted with GFRP composites were carried out as: Group (I): Six numbers of normal beam elements, Group (II): Twelve beams each addressing influence of strengthening, retrofitting the flexure zone and to compare their flexural capacity. Group (III) six beams each addressing the influence of strengthening, retrofitting the shear zones and to compare shear capacity. Group (IV) three columns each tested under axial load with and without wrapping and for retrofitting. The results indicate that there is an increase in the load carrying capacity of RC frame strengthened with GFRP composites wrapping to the extent of 16.07% and the retrofitted yielded RC frame regain its structural capacity to the extent of 10.02%.