Seismic Strengthening and Retrofitting of RC Structures Using Fibre Reinforced Composites

The conventional practices of strengthening RC elements like Reinforced Concrete (RC) jacketing, Ferro cement jacketing, and Steel jacketing lead to an increased cross-sectional size of the member, which interrupts the functionality and proves to be nondurable when exposed to an aggressive environment. The use of Fiber Reinforced Polymer (FRP) composite technique in strengthening work addresses these issues over the other conventional practices. The simpler execution practice, high strength-to-weight ratio and faster setting time make FRP an efficient material in RC strengthening works. Many varieties of FRP, such as Glass, Carbon, Basalt, Aramid, etc., are available in construction practice that have unique tensile properties. The properties of tensile strength, Young’s modulus and rupture strain of FRP play a major role in the strength and post-yield deflection of the associated RC members. The property of adhesive used as a bonding source between FRP and concrete plays a significant role in transferring the forces and determining the failure mode. Strengthening techniques primarily depend on the demand/deficiency of structural elements. This chapter presents an overview of the strengthening techniques and experimental behaviour of FRP-strengthened RC elements.