EXPERIMENTAL STUDY ON SEISMIC PERFORMANCE AND SECTION BENDING MOMENT ANALYSIS METHOD for ENERGY CONSUMPTION CONCRETE FILLED STEEL TUBE SLOTTED COLUMNS

The energy consumption concrete filled steel tube slotted (EC-CFSTS) column is proposed by applying slotted form to multi-cavity CFST columns and installing shear dampers in gaps. The novel composite column has good deformation capacity and excellent aseismic performance, which can utilize the shear energy dissipation of the damps. The study conducted low cycle tests on EC-CFSTS columns and analyzed the effects of axial compression ratio and damper length on the aseismic performance. The research results indicate that the new composite column has good plastic deformation and energy dissipation capacity. The EC-CFSTS column shows full section rotation in the early loading stage, which show good initial stiffness. After yielding, the specimen shows dislocation in gaps, the dampers begin to transmit shear force and dissipate shear energy. After the peak load, the specimens show individual section rotation, and the horizontal expansion in the middle of the column causes the damper to exit operation. The axial compression ratio and addition dampers can improve the peak load and the energy dissipation capacity of the novel column. And there is a synergistic relationship between the damper and the CFST slotted column. Based on the experimental results, the analysis method of moment-curvature relationship was proposed for the EC-CFSTS column. The deformation law and collaborative deformation mechanism of the section rotation were further analyzed. And the corresponding theoretical calculation method was established.