Rapid repair of earthquake-damaged reinforced concrete columns using fiber-reinforced plastics

The research described in this document was used to develop a rapid repair technique for reinforced concrete bridge columns with severe damage in their plastic hinge regions. The repair was intend to be a quick procedure to tentatively allow for the bridge to be open to traffic until the bridge is thoroughly repaired or replaced at a later date. The design criterion for the repair was to restore the original strength and to provide a minimum level of ductility capacity.;Two 40 percent flared columns, initially damaged under cyclic loads in a previous study, were repaired and tested under the lateral cyclic loading in this research. The repair schemes were characterized by the use of fiber-reinforced plastics (FRP) with longitudinal composite fiber reinforcement to replace the broken bars and transverse composite fibers to enhance the shear strength and confinement for the columns. The repair method restored the strength of the columns and provided a displacement ductility capacity of at least 3.;Due to the good performance during the testing, the repair method that was developed in this study is recommended for use. The response of the repaired columns can be predicted using the lumped composite section method which was evaluated in the analysis study.