Abstract:The connection between concrete-filled steel tube column and reinforced concrete beam in the prefabricated concrete filled steel tube structure has been a complicated issue.In this study,a new type of concrete filled steel tubular column and concrete beam connection was first designed to satisfy the requirement from the prefabricated construction process,enabling the prefabrication of most assembly parts and rapid assembling at the construction site.Five beam-column connection specimens,three intermediate connection and two end connection,were prefabricated.All the five specimens were tested in the laboratory;one of them was subjected to static and monotonic loading in order to check the bearing capacity and deformation capability of the connection,while the other four were tested under cyclic loading.The failure modes,hysteretic behavior,ductility,energy dissipations and degradations of strength and stiffness of the tested specimens were obtained.It was observed that the ultimate failure occurred at the composite beams,conforming to the basic design concept of strong column,weak beam and strong joint,weak member.The recorded hysteresis curves of the specimens with composite beam cross-section of 200 mm×350 mm were relatively plump without apparent knead shrinkage phenomenon,the ductility coefficient varied from 3.77 to 6.60,and the average equivalent viscous damping coefficient was 0.222,revealing favorable seismic energy dissipation capacity.For the specimens with composite beam cross-section of 250 mm×450 mm,the energy dissipation capacity of the connections were not fully developed due to the limited stirrup reinforcement,resulting in shear-compression failure.The length of the stirrup reinforcement district can be extended to enhance the energy dissipation capacity of the connection.Moreover,stable degradation process of strength and stiffness was also demonstrated since most of the strength degradation coefficients of specimens were found to be higher than 0.9.The yielding strength has not been exceeded for all the T-shaped plates in the tested connections,and the design of the T-shaped plate with bending and shear capacities being 1.3 times those of the connected concrete beam is confirmed to be reliable.