焊接T形截面轴心压杆的弯扭屈曲

《钢结构设计规范》(GB50017-2003)提出采用换算长细比法对单轴对称截面绕对称轴失稳按弯扭屈曲计算,该方法是否合理,各文献看法不一。借助有限元分析软件对焊接T形截面压杆的弯扭屈曲进行了几何非线性与物理非线性分析,考虑残余应力和几何缺陷的影响,并与“规范”(GB50017-2003)计算结果相比较。结果表明:规范值和文中计算结果吻合较好,规范是合理的、安全的、经济的。

FLEXURAL-TORSIONAL BUCKLING OF WELDED T SECTION STRUTS

The buckling of struts with mono-symmetric section about symmetrical axis is taken as flexural-torsion buckling, which can be calculated with the method of conversion slenderness ratio according to the current “Code for Design of Steel Structure” (GB 50017-2003). Whether it is rational or not, views of each reference are different. The analysis of geometric and material non-linearity for flexural-torsional buckling of struts with welded T section is made using the finite element method, in which the factors such as residual stresses and geometric imperfections are considered. Based on this, the code results are compared with the calculation results by finite element method. The study shows that flexural-torsional calculation formulas provided by code (GB 50017-2003) agree well with the calculated results, and the code is rational, safe and economical.