be superior to other common dissipative structures with global respect to cost efficiency for the following reasons: Buckling-restrained braces have energy dissipative behavior that is much improved from that of Special Concentrically Braced Frames (SCBFs). Also, because their behavior factor is higher than that of most other seismic systems (R=8), and the buildings are typically designed with an increased fundamental period, the seismic loads are typically lower. This in turn can lead to a reduction in member (column and beam) sizes, smaller and simpler connections, and smaller foundation demands. Also, BRBs are usually faster to erect than SCBFs, resulting in cost savings to the contractor. Additionally, BRBs can be used in seismic retrofitting. Finally, in the event of an earthquake, since the damage is concentrated over a relatively small area (the brace's yielding core), post-earthquake investigation and replacement is relatively easy. An independent study concluded that the use of BRBF systems, in lieu of other earthquake systems, produced a savings of up to $5 per square foot. Disadvantages Buckling restrained braces rely on the ductility of the steel core to dissipate seismic energy. As the steel core yields, the material work-hardens and becomes stiffer. This work hardening can represent increases in the expected force of up to 2x the initial yield force. This increased stiffness decreases the building's period (negating some of the initial increases) and increases the expected spectral acceleration response requiring stronger foundations and connection strengths. Buckling restrained braces rely on ductility and generally must be replaced after usage during a major earthquake. Reference structures Intermountain Medical Center Levi's Stadium - home of the San Francisco 49ers L.A. Live - hotel and residences One Rincon Hill tower Washington Mutual tower, office building Rio Tinto Stadium - home of the Major Soccer League team Real Salt Lake. See also S. Hussain, P. V. Benschoten, M. A. Satari, S. Lin: Buckling Restrained Braced Frame Structures: Analysis, Design and Approvals Issues L. Calado, J. M. Proenca, A. Panao, E. Nsieri, A. Rutenberg, R. Levy: Prohitech WP5, Innovative materials and techniques, buckling restrained braces Bonessio, N., Lomiento, G., Benzoni, G., (2011). An experimental model of buckling restrained braces for multi-performance optimum design. Seismic Isolation and Protection Systems, Vol. 2, No. 1, pp. 75–90. References Earthquake engineering Structural steel Nippon Steel