| Spatial steel frame-steel tube concrete column is new kind of composite column.In previous studies,most people ignore the constrain function of the spatial steel frame to concrete outside of the steel tube,and regard this part of concrete as the ordinary concrete.After a lot of experimental research and theoretical analysis,the result show that the constrain function of the spatial steel frame to its core concrete is quite obvious and it can not only improves the concrete strength and deformation capacity but also improves the seismic performance of spatial steel frame-steel tube concrete column.This paper mainly research on the seismic performance and mechanical behavior of the spatial steel frame-steel tube concrete column.The subject designed 6 Spatial steel frame-steel tube concrete columns and a double Spatial steel frame concrete column with the parameters including the axial compression ratio,spatial steel frame steel ration and steel arrangement both of inside and outside steel.Through the analysis of the parameters including failure modes of the specimens,the hysteretic curves,the skeleton curves,the energy-dissipation capacity,the ductility,the stiffness and bearing capacity degradation,the text result show that with the decrease of axial compression ratio or with the increase of steel reinforcement ratio of spatial steel frame,the hysteresis curve is more full,the stiffness and bearing capacity degradation is more slowly,the energy-dissipation and deformation capacity is better with other conditions unchanged.The validation of the text of spatial steel frame-steel tube concrete column was analyzed by ABAQUS finite element software.And the influence of parameters such as the axial compression ratio,confinement index of concrete-filled steel tube and spatial steel frame steel ration,the spacing and its width of the lacing bar of spatial steel frame etc.on the seismic performance and the mechanical behaviors of spatial steel frame-steel tube concrete columns was analyzed.The result show that all of these parameters can influence the seismic performance and the mechanical behaviors of spatial steel frame-steel tube concrete column.Furthermore,the analysis result indicates that the axial compression ration,confinement coefficient of spatial steel frame concrete and the confinement index of concrete-filled steel tube were the dominant influential factors of the bearing capacity of spatial steel frame-steel tube concrete column. |
