In order to investigate the mechanical properties of concrete-filled tube columns with a wider range of confinement factors under axial compression, 14 specimens, including plain concrete columns and concrete-filled PVC, plexiglass and steel tube columns are subjected to axial compression. The axial load-displacement curves and damage process of the columns are analyzed, and the results indicate that the ultimate axial compressive strength of the concrete-filled tubes increases as the confinement factor ascends. The stiffness and deformation capacity of columns with lower hoop restraint increase as the confinement factor ascends. The axial load-displacement curve of concrete-filled steel tube (CFST) columns with higher confinement factors can be divided into five stages, and the secondary strengthening effect of CFST columns is discovered and explained. The nominal Poisson's ratio of the steel tube under triaxial stress is derived by the elastic property and the geometric parameters of the concrete and tube. The local initial yield of the steel tube is discovered based on the plastic yield theory, which precedes the entire yield of the CFST columns. Theoretical formulas of the ultimate bearing capacity for the CFST columns based on the four yield criteria are presented and the present results are compared with the values calculated by the typical codes and the experimental results. The value calculated by Tresca yield criterion is more conservative and safer, so it is an appropriate reference for the lower limit design of axial compressive capacity of CFST columns.

为了研究具有更宽约束系数的管状混凝土柱在轴压作用下的力学性能，对素混凝土柱和PVC、有机玻璃和钢管柱等14个试件进行轴压试验。分析了柱的轴向荷载-位移曲线和损伤过程，结果表明，随着约束系数的增加，混凝土管的极限轴向抗压强度增加。随着约束系数的增加，具有较低环箍约束的柱的刚度和变形能力增加。具有较高约束系数的钢管混凝土（CFST）柱的轴向荷载-位移曲线可分为五个阶段，发现并解释了CFST柱的二次强化作用。三轴应力作用下钢管的公称泊松比是由混凝土和钢管的弹性特性和几何参数推导出来的。钢管的局部初始屈服是基于塑性屈服理论发现的，它先于 CFST 柱的整体屈服。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型规范计算的值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。钢管在三轴应力下的比值由混凝土和钢管的弹性特性和几何参数推导出来。钢管的局部初始屈服是基于塑性屈服理论发现的，它先于 CFST 柱的整体屈服。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。钢管在三轴应力下的比值由混凝土和钢管的弹性特性和几何参数推导出来。钢管的局部初始屈服是基于塑性屈服理论发现的，它先于 CFST 柱的整体屈服。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。钢管的局部初始屈服是基于塑性屈服理论发现的，它先于 CFST 柱的整体屈服。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。钢管的局部初始屈服是基于塑性屈服理论发现的，它先于 CFST 柱的整体屈服。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。提出了基于四个屈服准则的 CFST 柱极限承载力的理论公式，并将当前结果与典型代码计算值和实验结果进行了比较。Tresca屈服准则计算的值更保守、更安全，可作为CFST柱轴压承载力下限设计的适当参考。