RETROFITTING SFRC BEAMS BY USING CFRP

Abstract

The use of structural members made of steel fiber reinforced concrete (SFRC) has been increasing since it has been shown through numerous researches that steel fibers promotes the mechanical properties of concrete beyond cracking and improve the crack control characteristics of concrete significantly. A particular use of steel fibers aims to enhance the behavior of reinforced concrete (RC) beams without web reinforcement. Even thouh there have been numerous researches focused on the contribution of steel fibers to the behavior of  reinforced concrete (RC) beams without web reinforcement, the studies on retrofitting of SFRC beams is very limited. An advantegous retrofitting method is to use carbon fiber reinforced polymers (CFRP) due to the fact that it has relatively high tensile strength and low weight, and it can be applied easily and rapidly. In this study, RC beams with a shear span-to-effective depth ratio of 4.5 were loaded up to their load-carrying capacities and then tested again after retrofitting with CFRP. The experimental results were examined in the context of strength, stiffness and ductility.

Keywords

• Reinforced concrete,beam,steel fiber,carbon fiber reinforced polymer

References

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