加劲肋对方钢管混凝土轴压短柱局部屈曲性能的影响

Effects of Longitudinal Ribs on the Local Buckling Behavior of the Short Concrete Filled Square Steel Tubular Columns under Axial Loading

基于对加纵肋薄壁方钢管混凝土短柱在轴压荷载下局部屈曲性能的理论分析,利用能量法,推导了当加劲肋与壁板发生整体屈曲时,设置多条纵向加劲肋数量时加肋壁板的屈曲应力计算公式,在此基础上对比分析了影响单肋、双肋、三肋方钢管混凝土短柱临界屈曲系数大小,结果表明,增加加劲肋数量对提高壁板局部屈曲系数作用并不显著,在加劲肋总截面面积不变的情况下,加劲肋数量增加甚至会使壁板局部屈曲系数有所降低,增加加劲肋刚度对改善壁板局部稳定最为有效。本文结论可为带肋方钢管混凝土设计提供参考。

On the basis of the theoretical analysis of the local buckling behavior of short concrete‐filled square thin‐walled steel tubular columns with ribs under axial loading ,the formulae for calculating local buckling stress of the stiffened square tubes with multilateral longitudinal ribs under a combined deformation of the longitudinal ribs and steel tubes is deduced using en‐ergy approach .And the critical buckling coefficient of the short concrete‐filled square thin‐walled steel tubular columns with single‐ribs ,double‐ribs and three‐ribs are analyzed and compared respectively .The results show that local buckling coeffi‐cient of the steel tubes rises insignificantly with the increase of the number of the ribs or even falls if under the same condi‐tion the total area of the across‐section of the longitudinal ribs are a constant ,and increase of the stiffness of the longitudinal ribs can most effectively enhance the local stability of the ribbed tubes .The conclusions in this paper may be a reference for the columns design .