中文摘要：

为了研究冷弯薄壁型钢拼合截面柱的轴压承载力，对各国有关冷弯薄壁型钢拼合截面柱的轴压试验进行了ANSYS有限元模拟分析，有限元计算结果与试验结果吻合良好，从而验证了有限元方法的正确性。采用有限元方法分析了构件截面形式、截面尺寸以及长细比对冷弯薄壁型钢拼合截面柱拼合效应的影响，提出了冷弯薄壁型钢拼合截面柱轴压承载力的简化计算方法。分析结果表明：随着长细比的增大，拼合截面柱的拼合效应随之增大。对于主要通过螺钉将腹板进行拼合的构件，当翼缘宽厚比一定时，随着截面宽高比的增大，腹板拼合的整体性增强，从而使拼合效应增大，而截面面积的改变对拼合效应的影响则不是很明显。

英文摘要：

In order to investigate bearing capacity of cold-formed steel built-up columns under axial compression, authors used ANSYS finite element program to analyze the cold-formed steel built-up columns at home and abroad. Compared with experimental results, the validity of the finite element method （FEM） was verified. Furthermore, a detailed parametric study by FEM was carried out to mainly determine the influence of cross-section form, cross-section dimension and slenderness ratio of component for the built-up effect. The simplified calculation method to the bearing capacity of cold-formed steel built-up columns under axial compression was extracted. The analytical results show that with the increase of the slenderness ratio, the built-up effect improves. As for these columns connected with screws through web, when width-thickness ratio of flange is certain, with the increase of width-height ratio of cross-section, the integrity of the built-up web increases, which leads the built-up effect to strengthen. But the influences of different areas of cross-sections are not so obvious.