贺虎成，周  霞，王洪西，张湘冀
(总装备部工程设计研究总院，北京100028)

[摘要] 上海佘山森林剧场网壳是跨度为92m.高27.8m的双层椭球体网壳。基于有限元ANSYS结构分析程序，建立了网壳结构的空间有限元模型，计算了网壳的静力性能。系统分析了不对称分布荷载作用下，网壳的特征值屈曲荷载和考虑初始缺陷、几何非线性、几何材料双重非线性时网壳结构的极限荷载。结果表明，几何、材料双重非线性、荷载的不对称分布对该网壳结构的极限承载力影响很大。为类似结构的工程设计、计算提供参考。
[关键词] 网壳；稳定性分析；几何非线性；材料非线性；初始缺陷；不对称荷载

    Stability Analysis of Net Shell Structure for Shanghai Sheshan Forest Theater
    He Hucheng, Zhou Xia, Wang Hongxi, Zhang Xiangji
    (Center for Eng. Design and Research under the General Equipment Department, Beijing 100028, China)

Abstract: Net Shell of Shanghai Sheshan Forest theater is a doublelayer spheroidal steel tube structure with a span of 92m, height 27.8m. The net shell's 3D finite element model was created by structrual analysis program ANSYS, and it's static performance was calculated. The ultimate load and eigenvalue buckle load for the net shell were systematically analysed under unsymmetrical loading. The nonlinear stability calculation of the shell was performed based on considering its initial geometrical imperfection, geometric nonlinearity, double nonlinearity of geometric and material. The results show that the ultimate bearing capacity of the shell is determinated by unsymmetrical loading and the double nonlinearity of geometric and material. It has provided a reference for the design and calculation of similar engineerings.
Keywords: net shell;  stability analysis;  geometrical non-linearity;  material non-linearity;  initial geometrical imperfection;  unsymmetrical loading