Seismic performance of self-centering precast concrete buckling-restrained braced frame sub-assembly

Buckling-restrained braces (BRBs) are highly effective lateral force-resisting and energy-dissipating components, widely utilized in seismic-resistant structures, particularly in steel frames. This study presents an improved design for self-centering precast concrete buckling-restrained braced frames (BRBSCFs), achieved by: (1) incorporating precast post-tensioned (PT) elements into both beams and columns, and (2) connecting the BRBs to regions away from the joint areas. This design approach preserves the favorable rocking behavior of beam–column and column-base connections. Four cyclic loading tests were performed on a single-story, single-bay prestressed precast frame subassembly equipped with a BRB. The failure modes, hysteretic behavior, PT force response, stiffness, and re-centering capacity of the BRBSCFs were analyzed. Results demonstrated that the BRB components contributed approximately 40% of the total load-carrying capacity and provided nearly all of the energy dissipation . The PT connections enabled self-centering behavior, reducing the residual drift to approximately 30% of the peak drift during loading. Numerical simulations were conducted to validate the experimental findings, followed by parametric analyses to assess the effects of the BRB core unit width-to-thickness ratio, prestressing tendon diameter, initial prestress force , and core unit steel types on the seismic performance of the frames. Increasing the cross-sectional area of the PT tendons was identified as an effective strategy for enhancing the strength of BRBSCFs. The study concludes with a discussion of its limitations and potential avenues for future research. • Buckling-restrained braced self-centering precast concrete frame are proposed. • BRB gusset plates are connected only to the precast columns. • Cyclic loading tests are conducted on the novel frame with and without BRBs. • BRBs provide good energy dissipation capacity to the precast concrete frame. • Improved detailing of BRB connections is required for a better hysteresis behavior.