Shear retrofitting of reinforced concrete beams with steel fiber reinforced concrete

Abstract

With the objective of evaluating the performance of steel fiber reinforced concrete (SFRC) as a retrofitting material for reinforced concrete beams the experimental study of reinforced concrete beams repaired and strengthened with a SFRC jacketing and tested under shear is presented in this paper. The reinforced concrete beams were designed with high amount of longitudinal steel and minimum transverse reinforcement so that they present shear failure. Some of the beams were strengthened with very fluid high strength SFRC jacketing and some of them were first tested under shear to produce some damage and then they were repaired with the same technique. Plain concrete and SFRC with two different fiber dosages, 30 kg/m3 and 60 kg/m3, were used for the reinforcement. The experimental program showed the possibility of performing the retrofitting at work place. The repaired beams showed excellent strength and deformation capacity restitution. The strengthened beams exhibited increase of load bearing capacity. The addition of fibers to the concrete played an important role in the prevention of the jacketing debonding from the beams.