Seismic behavior of double steel plate-HSC composite walls

Double steel plate-high strength concrete composite wall (DSP-HSCW) is a new lateral force-resisting system, with concrete filled steel tube (CFST) column as boundary element. The wall combines the favorable strength and stiffness characteristics of high performance concrete (HSC) with the ductility of the steel plate. A series of tests were conducted to investigate the response of the DSP-HSCW system under cyclic loading. The parameters investigated in the tests included the axial-load ratio (applied axial load to bearing capacity) and the ratio of the tie bar spacing to steel plate thickness. The test results showed that unlike conventional HSC walls, the wall specimens exhibited high strength as well as excellent deformation capacity. The wall specimens with large height-to-width ratio showed flexure-dominated behavior through cantilever action. The primary failure mode is axial-flexural mode, which is characterized by local buckling of the steel plates followed by compressive crushing of concrete at the wall bottom. The axial-load ratio has a significant effect on the strength and deformation capacity of DSP-HSCW system. To enhance deformation capacity to meet a specific demand, the ratio of the tie bar spacing to steel plate thickness should be reduced. The paper adds to existing research database on the performance of DSP-HSCW under lateral demands and provide valuable insight on the performance of such system.