With Newton-Raphson and arc-length calculation method, this paper has made research on effect of tapering ratio, web plate width-thickness ratio and slenderness ratio on ultimate bearing capacity.

• 利用牛顿-拉弗森法和弧长法对荷载-位移平衡路径进行跟踪研究，研究了翼缘宽厚比和腹板宽厚比对结构极限承载力的影响；