Retrofit of Circular Reinforced Concrete Columns Using FRP, Steel and Concrete Jackets

A large number of reinforced concrete (RC) buildings and bridges is deemed structurally deficient. This is either because the infrastructure continues to age and deteriorate or the strength or deformation capacity of the existing older infrastructure does not meet the current code requirements, e.g., in high seismic regions. Thus, the need for more efficient retrofit methods has increased in recent years. Currently, there are only a few methods used for strengthening or retrofitting columns. Steel jackets and Fiber Reinforced Polymer (FRJP) composites are the two most commonly used methods. In this study, along with these two retrofit methods, concrete jackets reinforced with spiral rebar, Welded Wire Fabric (WWF), and a new steel reinforcement termed PCS are investigated under different axial load conditions.