Case Study of the Seismic Upgrade of a Critical Facility Using Spliced Buckling Restrained Braces

December 30, 2010
Publication: SEAOC 2010 Convention Proceedings, Structural Engineers Association of California
Author(s): Dutta, Anindya McCormick,David L. Tam, Kenneth T. Goings, Craig B. Mayes, Ronald L.

Abstract: This paper presents the analytical approach and associated laboratory testing of spliced Buckling Restrained Braces (BRBs) required for the seismic upgrade of a critical facility located in the city of South San Francisco. As part of an earlier seismic upgrade, several new braced frames were designed to be added in the longitudinal and transverse directions. However, this work was only 60% completed when Simpson Gumpertz and Heger (SGH) was asked to evaluate the building in its as built state. We found several issues with the existing and new braces including weak connections that did not develop the brace strength. Due to the extremely congested interiors SGH suggested a combination of interior spliced BRBs and an exterior buttress scheme. The details of the analysis and validation tests of the spliced BRBs are presented in the paper.