Seismic performance investigation of new buckling-restrained steel plate for resilient rocking column foot joint

Seismic damage-controllable components and design approaches are crucial for achieving the seismic resilience and post-earthquake recovery of building structures. To improve the seismic resilience of reinforced concrete (RC) frame structures, this study proposed a novel assembled replaceable rocking column foot joint. The column foot joint is composed of a concrete foundation, short steel-tube concrete column in the center, and four new buckling-restrained steel plates (BRSPs) on the periphery. A detailed design method for the BRSPs was developed, and six BRSP specimens were designed with different core weakening forms and thicknesses. The specimens were cyclically tested and the failure mode and hysteresis behavior were examined. The test results confirmed that the proposed BRSPs exhibit satisfactory energy-dissipation capacity and achieve damage control. The refined numerical models were developed using ABAQUS and verified using the test results. Parametric analyses were conducted for the BRSPs to examine the influence of core plate thickness, gap size, and restraint plate thickness. A numerical analysis model of the column foot joint was established, and the influence of the axial compression ratio and BRSP bearing capacity on the seismic performance of the column foot was investigated. This study provides a reference for the construction of resilient RC frame structures.