初始几何缺陷对仓壁柱承钢筒仓稳定性能的影响
THE EFFECT OF INITIAL GEOMETRIC IMPERFECTIONS ON STABILITY BEHAVIOR OF COLUMN-SUPPORTED STEEL SILOS WITH ENGAGED COLUMNS
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摘要: 仓筒壁直接支承于支柱是小型钢筒仓的一种简单、经济的支承方式。薄壳结构通常对初始几何缺陷十分敏感。引入周向轴对称焊缝凹陷和特征值屈曲模态两种缺陷形式,通过几何非线性分析,研究初始缺陷对轴压下仓壁柱承筒仓稳定性能的影响。研究表明,周向焊缝凹陷会显著降低结构的屈曲荷载,且与焊缝位置密切相关,而特征值模态缺陷只有在支柱接近仓顶时才会显著影响其屈曲强度。Abstract: Supporting silo walls directly on engaged columns provides a simple and cost-effective support arrangement for light steel silos. Thin shell structures are generally very sensitive to initial geometric imperfections. By introducing two patterns of imperfections including circumferential weld depressions and eigenmode-affine imperfections, the effect of initial imperfections on stability behavior of axially compressed column-supported steel silos with engaged columns is investigated through geometrically nonlinear analyses. It has been shown that circumferential weld depressions lead to a significant reduction in the buckling load which is closely related to the welding location, while eigenmode-affine imperfections affect the buckling load remarkably only when the engaged columns extend to the top of the silo wall.