Experimental study on seismic performance of composite structure of steel column-integrated prefabricated concrete wall with different connection types

The composite structural members formed by steel frame and internal concrete wall have superior seismic performance. In order to reveal the seismic performance of composite structure of steel column-integrated prefabricated concrete wall with different connection types (fixed beam-column joint and welded column side, fixed beam-column joint and unwelded column side, hinged beam-column joint and welded column side, hinged beam-column joint and unwelded column side), the low-cycle reversed loading test was carried out on the 1/2 scale specimen of four steel column-integrated internal diagonal bracing concrete wall(SC-IBW) with different connection types. The hysteretic curves and skeleton curves were presented, and the effects of different connection types on the seismic performance and mechanical mechanism of the specimens were obtained by analyzing the test phenomena, bearing capacity, stiffness, energy dissipation, ductility, strain and deformation of different specimens. The test results show that: SC-IBW exhibits three seismic defenses, among which the concrete wall is the first seismic defense, the internal bracing is the second seismic defense, and the confining frame is the third seismic defense. Column sides welding has the most obvious influence on the bearing capacity, stiffness and the composite efficiency between frame and inner wall; the internal bracing contributes significantly to the stiffness of SC-IBW and plays a key role in the composite efficiency between the confining frame and inner wall. The ductility factor of the SC-IBW with hinged joints and unwelded column sides reaches 2.83, which indicates that 1/20 can be recommended as the limit of maximum elastic-plastic drift ratio. The ductility factor of SC-IBWs with other connection types is from 1.22 to 1.53, and 1/100 is recommended as the limit of maximum elastic-plastic drift ratio. The SC-IBW, with hinged joints and unwelded column sides, is recommended to the structural design controlled by displacement. However, the SC-IBW, with rigid joints and welded column sides, is recommended to the structural design controlled by bearing capacity. © 2020, Editorial Office of Journal of Building Structures. All right reserved.