初始几何缺陷对网壳截面优化结果影响研究

THE INFLUENCE OF INITIAL GEOMETRIC IMPERFECTION ON THE SECTION OPTIMIZATION RESULT OF RETICULATED SHELL

  • 摘要: 单层网壳结构是缺陷敏感结构,初始几何缺陷不同对"网壳截面优化结果"有显著影响,该文研究了网壳杆件截面取值与缺陷分布、结构极限承载力之间的关系.结果表明:经截面优化设计的网壳结构最不利应力最早并且一直出现在初始几何缺陷较大处;优化寻优结果与初始几何缺陷分布有直接关系,增大缺陷较大处杆件截面能显著提高结构承载力;由于缺陷随机分布,经截面优化设计的网壳结构须校核其在不同缺陷下的稳定承载力以确保结构安全.

     

    Abstract: The single layer reticulated shell is a kind of imperfection sensitive structure. The initial geometric imperfections have a significant impact on the section optimization results of the shell. This paper studies the relationship among the rod section optimization value, the initial geometric imperfection distribution, the ultimate bearing capacity and the member buckling failure law of the structure. It is indicated that the most unfavorable stress appears early and keeps growing until the buckling failure in the place where the initial geometric imperfection is larger on the structure after the section optimization design. The section optimization results are directly related to the initial geometric imperfection distributions, which means that increasing the cross-section of the rod where the initial geometric imperfection is larger would effectively enhance the ultimate stability bearing capacity. Due to the random distribution of the initial geometric imperfection, the stable bearing capacity of the reticulated shell after the section optimization design must be checked under different defect distributions to ensure safety.

     

/

返回文章
返回