Experimental study on seismic behavior of space steel frame with reduced beam section connections

In order to investigate the seismic behavior of steel frame with reduced beam section (RBS) connections, the test loading device was designed, and a 1 ∶3 scaled two-story and two-bay space steel frame with reduced beam section connections was tested under low cyclic loading to study the stress characteristics and failure mode, and analyze the loading-displacement hysteretic loop, skeleton curve, stiffness degradation, bearing capacity degeneration, plastic energy dissipation capacity of the frame. The experimental results indicate that all plastic hinges of the space steel frame form at the reduced arc region of the eight RBS connections. All beam-column connections have not any weld cracks. The load-displacement hysteretic curves are full, with the displacement ductility ratio between 3.05 and 3.82. The equivalent viscous damping coefficient ranges from 0.34 to 0.41. The elasto-plastic ultimate inter-story drift angle varies from 0.0355 to 0.0445 rad. The steel frame beam-column connections which use arc-type RBS joints exhibit smooth stress transfer and can avoid the stress concentration, and the plastic internal force redistribution of the steel structure has no obvious effects on the energy dissipation capacity of the arc-type RBS joints. The arc-type RBS joints in steel frame exhibit better ductility, and can improve the seismic behavior and plastic energy dissipation capacity of the structure. © 2016, Editorial Office of Journal of Building Structures. All right reserved.