钢管混凝土X形交叉柱轴压性能研究

To study the axial compressive behaviour of a novel composite column with irregular and variable cross-sections, namely concrete-filled steel tubular X-column (CFST X-column), which is consists of two inclined circular or long-circular concrete-filled steel tubular columns placed crosswise, ABAQUS finite element models of the CFST X-column are developed and verified by using the existing experimental results. The whole mechanical process of circular and long-circular CFST X-column under compression was analyzed, and a parametric analysis was conducted. Simulation results have shown that the concrete is unevenly confined by the steel tube in the cross area of the CFST X-column. The highest and lowest confinement effects are observed on the core area of the concrete section and steel tube crossing region, respectively. The confinement on the left and right areas are between the above two areas. Separation occurs between the steel tube and concrete on some sections. With the increase of the concrete and steel tube strength, the thickness of the steel tube, and the intersection angle, the axial compression capacity of the CFST X-column is enhanced.