Seismic behavior of prefabricated frame with special-shaped concrete-filled steel tubular columns and H-shaped steel beams

To realize the prefabricated structure of special-shaped concrete-filled steel tubular (CFST) column frame and enhance the level of indoor room utilization, this paper proposed a novel prefabricated frame with special-shaped CFST columns and H-shape steel beams connection with side plate. To investigate seismic behavior of this prefabricated frame structure, a 2-story and 2-bay CFST frame specimen was fabricated and tested under reversed cyclic loading. The failure mode, hysteresis behavior, degradation of lateral stiffness and bearing capacity, ductility and energy dissipation were analyzed. Experiment results indicated that failure mode presented strong columns and weak beams. Hysteresis curve of frame showed fully shuttle-shaped. The mean story drift angle was 1/36 at ultimate stage. Equivalent viscous damping coefficient was 0.038-0.464. The bearing capacity degradation was relatively gentle, but the overall stiffness degradation was more obvious. It suggested that the frame had proper seismic and energy dissipation property. After the test, the seismic property of test frame was further investigated through the numerical simulation approach. The failure mode and skeleton curve obtained from the simulation were nearly consistent with test results, indicating that numerical analysis results were precise and with high reference meaning.