Mitigation of seismic ratcheting for steel buildings with overhangs on only one side using tension-only braces

Buildings with overhangs on only one side are prone to seismic ratcheting, where inelastic deformation mostly occurs in the overhang direction during earthquakes. This study examines the potential of using tension-only braces to mitigate seismic ratcheting for steel frame buildings. Two types were considered: (i) traditional cable braces, and (ii) ratcheting braces which shorten in compression. It was found that the effectiveness of cable braces to mitigate seismic ratcheting decreases with each inelastic response cycle due to irrecoverable tensile strains. Ratcheting braces were more effective, but overdesign may cause seismic ratcheting to occur in the opposite direction instead.