带约束拉杆方形钢管混凝土轴压柱局部屈曲性能

假定方形钢管混凝土构件的钢管板件在非载荷边受到弹性约束,应用能量法对钢管局部屈曲强度计算公式进行了推导;并利用已有试验结果对计算公式的正确性进行了验证。在此基础上利用该公式对约束拉杆方形钢管混凝土构件在轴压下的屈曲性能进行分析,分析表明约束拉杆能有效提高构件钢管屈曲系数,从而提高钢管壁抵抗局部屈曲的能力。最后,给出了约束拉杆纵向间距的合理设置值以及带约束拉杆方形钢管混凝土轴压构件的钢管宽厚比限值。

LOCAL BUCKLING OF SQUARE CONCRETE-FILLED STEEL TUBULAR COLUMN WITH BINDING BARS UNDER AXIAL LOADING

Assumed that the steel plate is subjected to spring constrain at the unloading edge, the formulae for calculating local buckling strength of the steel plate of square concrete-filled steel tubular column under axial loading are deduced using energy approach, the validity of which was verified with experimental results. A further analysis on the effect of binding bars on local buckling of steel plate shows that the binding bars can enlarge the coefficient of local buckling and improve the capacity of steel plate to resist local buckling. Proper spacing of binding bars and appropriate limitation for width-thickness ratio of steel tube are suggested for square concrete-filled steel tubular column with binding bars under axial loading.