轴压作用下薄壁方钢管局部屈曲失稳的有限元分析

通过有限元模拟分析了轴压作用下薄壁方钢管的局部屈曲失稳形式．通过对一系列不同高宽比的方钢管模型的屈曲模态分析，研究了薄壁方钢管在轴压作用下发生局部屈曲失稳的规律．通过有限元模型分析，发现在轴向压力作用下，方钢管发生局部失稳破坏时，其临界荷载的大小主要受方钢管的宽厚比影响，而其高宽比对临界荷载的影响可以忽略不计．轴压作用下方钢管发生屈曲破坏时的屈曲系数非常接近于4，与四边简支的薄板在轴压作用下失稳的屈曲系数相同．这一结论对于薄壁方钢管在轴压作用下的屈曲分析具有参考价值．

Finite Element Analysis of Local Buckling of Thin-Walled Square Hollow Section Tube under Axial Compression

The local buckling mode of thin-walled square hollow section （SHS） tube under axial compression is analyzed using finite element method. The stability principle of thin-walled SHS tube under axial compression is investigated through the analysis of a series of numerical models with different height-width ratios. It is found from the finite element analysis that the critical load of the stability for thin-walled SHS tube under axial compression is mainly influenced by the width-thickness ratio, and the effect of the height-width ratio on the critical load can be ignored. The buckling coefficient of the thin-walled SHS tube under axial compression is very close to 4, and such value is same as the buckling coefficient of a hinged thin-walled plate under compression. This Conclusion is valuable for the stability analysis of thin-walled SHS tube under axial compression.