Design and Testing of an Enhanced-Elongation Telescoping Self-Centering Energy-Dissipative Brace

Abstract

The self-centering energy-dissipative (SCED) brace is a new steel bracing member that provides both damping and recentering capability to a structure, while reducing or eliminating residual building deformations after major seismic events. Previous SCED brace designs exhibited full self-centering capability over frame lateral deformations ranging from 1.5 to 2.0% of a typical building story height owing to the elongation capacity of the tendons comprising the system. To overcome this limitation, a new enhanced-elongation telescoping SCED (T-SCED) brace has been developed that allows for self-centering response over two times the range achieved with the original SCED bracing system. A prototype design of this proposed system was fabricated and tested quasi-statically and dynamically in a full-scale vertical steel frame. It exhibited full self-centering behavior in a single story frame that was laterally deformed to 4% of its story height. This new T-SCED brace also satisfied standard testing protocols for buckling restrained braces.