摘要

The bucking restrained braces (BRBs) could effectively improve the lateral stiffness and energy dissipation of the assembly concrete-filled steel tubular (CFST) composite frames. To study the failure mechanism and seismic performance of the assembly CFST frame with BRBs, two second-story one-span specimens with blind bolted endplate connections were tested under the lateral cyclic loading. The effects of column cross-section type and the endplate type on the seismic behavior of the whole structure were inspected. The failure mode and hysteretic curves were investigated in detail. Skeleton curves, strength and stiffness degradation, ductility and energy dissipation were also analyzed. The test results show that at the same steel ratio of the column section, the ultimate bearing capacity and initial stiffness of square CFST frame with BRBs are higher than those of circular CFST frame with BRBs. While the ductility coefficient and the energy dissipation capacity are on the contrary. The results of test and analysis show that the assembly CFST frame with BRBs has excellent seismic performance, ductility and energy dissipation capacity, so they can be applied and promoted in multilayer and high-rise composite structure buildings.