摘要
在总结各类稳定问题基本特征的基础上对稳定问题进行分类,将非线性分叉问题列为与分支点失稳、极值点失稳、跳跃失稳并列的第四类失稳。并将4种经典稳定判别准则中的初始缺陷准则应用于非线性有限元分析,提出了研究非线性分叉失稳的初始微小缺陷法。Williams肘形刚架为结构非线性分析的经典算例,为此设计了一点加载肘形刚架和三点加载肘形刚架,并对其进行了稳定性试验。理论计算和试验结果均表明,肘形刚架存在非线性分叉现象,揭示了初始微小缺陷是实际结构存在非线性分叉失稳的真正原因,也证明了初始微小缺陷法是可行和正确的。
On the basis of summarizing the basic characteristic of each kind of stability problem, a new stability classification opinion is put forward, which includes bifurcation point buckling, limiting point buckling, snap-through buckling and nonlinear bifurcation buckling. The initial imperfections criteria are put to use in the nonlinear finite element analysis, and the initial minute imperfect method is put forward to research nonlinear bifurcation buckling. The basic thought and the step of the method are referred to and the merit and shortcomings are analyzed. The method is used to research the behavior of three models of Williams＇ toggle frame and the models are experimented. Theoretical and experimental results all prove that the initial minute imperfect method is feasible and right.
出处
《钢结构》
2008年第3期51-56,共6页
Steel Construction
基金
教育部科学技术研究重点资助项目(105083)
