Design of Buckling-Restrained Braced Frames

The buckling-Restrained Braced Frame (BRBF) is a relatively new type of concentrically braced frame system. BRBF use the ductility of steel more effectively than conventional braced frames, such as Special Concentrically Braced Frames (SCBF) or Ordinary Concentrically Braced Frames (OCBF), which depend on brace buckling for their ductility. Buckling-restrained braces have been used extensively in Japan as hysteretic dampers within moment-resisting frames. These braces were introduced to U.S. design practice in 1999, and their use has been mostly as a building's primary seismic-load resisting system.