Response of Retrofitted 3D RC Frames under Dynamic Loading Conditions

Abstract

In this study, the response of 3D double story reinforced concrete (RC) frames retrofitted through a diagonal friction damper under dynamic loading conditions, was evaluated using shaking table tests. A friction damper having a simplified energy dissipation mechanism was designed, fabricated, tested under cyclic loads and used to strengthen the RC frames. The proposed damping device had a simple working mechanism and limited technical expertise were needed to fabricate and install. The damper was used as a joint region of a diagonal steel brace. The tested RC frames mimicked the non-seismic design of existing old structures in Korea. An artificial seismic ground motion record showing the characteristics similar to the Korean Earthquake histories, was used in the shaking table tests. The shaking table tests results demonstrated that the strengthened frames showed improved dynamic responses with reduced inter-story and residual drift ratios. The friction damping was effective in dissipating earthquake-induced energy and avoiding the potential bucking in diagonal steel brace.