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Abstract Moment-resisting Reinforced Concrete (RC) frames experience large inter-storey deformations during seismic events. These deformations result in permanent residual lateral drifts because of the post-yield response of the steel reinforcement. Following seismic events, the residual drifts usually complicate and/or prevent the repair of RC frames and make damaged RC structures unusable. Concentric bracing systems and passive energy dissipation devices have proven to be effective in limiting inter-storey drifts of RC frames but they failed to address residual deformations. The present study aims at minimizing seismic residual deformations using either Buckling Restrained Braces (BRBs) or Shape Memory Alloy Braces (SMABs). Two RC structures (low-rise and medium-rise) are designed twice utilizing BRBs or SMABs. A three-storey building represents the low-rise structures whereas a nine-storey building represents the medium-rise structures. Static push-over analyses are then conducted. The frames have also been subjected to twenty seismic ground motions. The responses of the two bracing systems are compared to evaluate their efficiency in reducing the seismic residual deformations. The study is then extended to evaluate the effect of using superelastic SMA reinforcing bars to reduce or eliminate seismic residual drifts in RC frames equipped with either SMABs or BRBs. Both the low-rise (three-storey building) and medium-rise (nine-storey building) structures are re-designed using SMA bars instead of regular steel bars in the plastic hinge regions of beams. While six design alternatives that differ in the position of the SMA reinforcing bars are considered in the two three-storey frames, eighteen alternatives are considered in the two nine¬storey frames. The deigned frames are then subjected to the same twenty seismic ground . |