Seismic design and tests of a full-scale one-story one-bay steel frame with a dual-core self-centering brace

• The paper presents seismic design and tests of a steel frame with a dual-core selfcentering brace.
• Eight tests were conducted on a full-scale one-story one-bay braced frame specimen to evaluate the system performance.
• The frame specimen had minor beam local buckling and no damage in the brace.
• Nonlinear time history analyses were conducted to obtain seismic demands of the prototype braced frame.

Traditional seismic resisting systems in a large earthquake can experience significant damage and residual drifts due to energy dissipation of structural members, which leads to difficult or expensive repairs. A steel dual-core self-centering brace (DC-SCB), which utilizes three steel bracing members, two friction devices, and two sets of tensioning elements that are in a parallel arrangement for doubling its axial deformation, has been proposed and validated to provide both the energy dissipation and self-centering properties to seismic resisting systems. A prototype three-story steel dual-core self-centering braced frame (DC-SCBF) was designed, and its full-scale first-story one-bay DC-SCBF was tested to (1) validate the system response, (2) study force distributions in framing members as damage progresses in the DC-SCB, beam or columns, and (3) investigate the repair and replacement characteristics of the frame. The DC-SCBF subassembly specimen showed beam and column yielding at 1% lateral drift, beam local buckling at 1.5% lateral drift and no damage in the brace at 2% lateral drift; the residual drift that was caused by beam yielding or local buckling was 0.3–0.5% after multiple tests. Nonlinear time history analyses were performed on the prototype braced frame to obtain seismic demands under both design and maximum considerable levels of earthquakes.