中文摘要：

利用叠加法对钢骨-方钢管高强混凝土柱的正截面承载力进行推导。把组合柱分为方钢管混凝土部分和钢骨部分,根据结构塑性理论的下限定理,对于给定的轴向力,由平衡条件任意分配方钢管混凝土部分和钢骨部分承担的轴力,并分别求出相应各部分的受弯承载力,两部分承载力之和的最大值即为钢骨-方钢管混凝土柱在该轴力下的受弯承载力。针对常用的内嵌十字形和工字形钢骨的情况,推导出叠加法的最终解作为组合柱正截面承载力的计算公式,并给出了组合柱的轴力与弯矩相关曲线。最后给出了一个算例。研究成果可为该组合柱在工程中的应用提供参考。

英文摘要：

Superposition method is used to calculate the bearing capacity of square steel tube column filled with steel-reinforced high-strength concrete.According to the lower limit theorem of plastic theory,the given axial force were arbitrarily distributed to square steel tube filled with concrete and steel section according to the equilibrium condition.Flexural strength of corresponding part was calculated respectively and maximum value of the sum of them was the bending capacity of the composite column.For composite columns with cruciform and I-shaped steel sections,ultimate solution had been deduced and regarded as the calculation formula for bearing capacity of the composite columns,and the N-M interaction curve is given as well.Finally an example is given to show the use of the calculation formula.The research results can provide reference for the engineering application of composite columns.