钢管混凝土组合柱耐火性能对比分析

采用非线性有限元软件ABAQUS对方钢管混凝土柱、复式钢管混凝土柱、内嵌十字型钢钢管混凝土柱和4腔钢管混凝土柱4种钢管混凝土组合柱开展火灾下的力学分析，并采用相关实验数据进行验证.分析不同荷载比下钢管混凝土组合柱的温度场、位移-时间曲线、截面内力重分布等.结果表明：内嵌型钢(钢管)有助于提升柱体的轴向刚度，钢管混凝土组合柱的破坏模态表现为压缩鼓曲破坏；低荷载比下内嵌钢管允许方钢管发生更高的温度材性劣化，进而提升了柱体的耐火性能，火灾荷载比越小，提升效果越显著.

Comparative Analysis of Fire Resistance of Concrete-Filled Steel Tubular Composite Columns

4 kinds of concrete-filled steel tubular(CFST)composite columns are analyzed by the nonlinear finite element software ABAQUS, and are verified by the relevant experimental data, including square CFST columns, composite CFST columns, embedded cross-shaped steel CFST columns and 4-cavity CFST columns. The temperature field, displacement-time curves and redistribution of internal force in the section of CFST composite columns under different load ratios are investigated. The results show that the embedded section steel(steel tube)is conducive to improve the axial stiffness of the column, and the failure mode of CFST composite columns is compressive drumming. Under the low load ratios, the embedded steel tube allows the higher temperature material deterioration of square steel tube, thus improving the fire resistance of the columnes. As the fire load ratio reduces, the effect improvement becomes more significant.