钢桁架屈曲分析研究

Research on buckling analysis of steel truss

以某钢桁架结构为主要研究对象,借助有限元软件,进行了结构选型和建模,对钢桁架结构屈曲问题和结构优化设计开展了研究分析,结果表明:侧向钢桁架邻近跨中的部位为结构最薄弱处,在外界荷载作用下,该区域易发生局部失稳;考虑初始缺陷的非线性屈曲分析相较于线性屈曲分析临界屈曲荷载系数明显降低,降低幅度在8.1%~39.1%;通过正交实验发现杆系的截面宽度对临界屈曲荷载系数的影响最大,截面高度和厚度的影响次之;利用非线性回归,得到了显著因素对临界屈曲荷载系数的预测公式。

Taking the steel truss structure as the main research object,structural selection,and modeling were carried out using finite element software.Research and analysis were conducted on the buckling problem and structural optimization design of the truss structure.The results showed that the area near the mid-span of the lateral truss is the thinnest and weakest point of the structure,which is prone to local instability under external loads.The nonlinear buckling analysis considering initial defects significantly reduces the critical buckling load coefficient compared to linear buckling analysis,with a reduction range of 8.1%to 39.1%.Through orthogonal experiments,it was found that the cross-sectional width of the rod system has the greatest impact on the critical buckling load coefficient,followed by the effects of cross-sectional height and thickness.By using nonlinear regression,a prediction formula for the critical buckling load coefficient of significant factors was obtained.