Today, key infrastructures are required to have usability and repairability after earthquakes. Based on the requirements of the new codes, a mechanical model of damage-controllable structure using fiber reinforced polymers (FRPs) is proposed. Hence, the aim of the study is to examine the required recoverability for existing and new structures. First, an intensive study on the inelastic performance of FRP-retrofitted bridge columns was conducted. The study showed that recoverability of such columns is probable. Subsequently, an advanced FRP-strengthening design guideline that considers and evaluates structural recoverability is proposed. Second, innovative reinforcing rebars (steel fiber composite bars (SFCBs)) were developed to enhance the post-earthquake recoverability of new reinforced concrete (RC) bridges. The performance of RC bridge columns reinforced with two types of the innovative rebars, i.e. steel basalt-fiber composite bar (SBFCB) and steel carbon-fiber composite bar (SCFCB), were experimentally studied. Furthermore, numerical studies were conducted to investigate the performance of bond-controlled structures reinforced with the innovative rebars. Experimental results showed that SFCBs, as longitudinal reinforcement, guarantee the gradual increase of column strength in the inelastic stage and substantially mitigate column residual deformations. In the light of the analytical results, concrete-to-SFCB bond would be a reasonable tool to control the required recoverability, where both column post-yield stiffness and residual deformations could be controlled.
