Abstract Seismically deficient structures require retrofits or upgrades to reinforce their lateral load resisting systems and ensure safe operation throughout remaining service life. Lateral braces can be used to reinforce the lateral load resisting system of a structure, but conventional brace designs suffer from sacrificiality as well as nonsymmetry in behavior due to buckling. A novel shape memory alloy (SMA) gear-based (GB) buckling-free brace (BFB) device (SMA-GB-BFB) was developed in this research to overcome limitations of conventional braces systems by presenting a reusable and symmetric bracing. Superelastic SMA is utilized due to its strain reversion capability alongside an innovative design approach that ensures symmetric behavior in both loading directions. A rack and pinion system is utilized to amplify applied strains by approximately two times, increasing energy dissipation rate. Proof-of-concept testing, which consisted of quasistatic material tests and quasistatic cyclic tests of the SMA-GB-BFB displayed a stable flag-shaped hysteretic behavior during applied motions, causing the device to sustain minimal damage while successfully dissipating energy via yielding of SMA strands.
Karfoul et al. (Sun,) studied this question.