椭球面弦支穹顶结构的稳定性

Stability Analysis of Ellipsoid Suspend-Dome

以上部网壳为椭球面的弦支穹顶结构为对象,用ABAQUS软件建模,考虑初始缺陷、布索方式及预应力水平等影响因素,进行几何非线性及同时考虑几何非线性和材料非线性的稳定性分析,分析时采用弧长法跟踪平衡路径,得到不同参数下结构的荷载-位移曲线.通过对比分析各参数下荷载-位移曲线及稳定极限承载力,椭球面弦支穹顶结构的稳定性能较单层网壳有了大幅度提高,初始缺陷的存在降低了结构的稳定承载力.此外,不同布索方式和预应力水平对结构的稳定承载力有较大的影响,应进行优化设计.

An ellipsoid suspend-dome was modeled and analyzed by using ABAQUS software. Both geometric nonlinear buckling analysis and dual nonlinear buckling analysis were conducted considering the variation of initial geometrical imperfection, cable arrangement and prestress level. Arc-length method was used to trace the equilibrium path so that the load-displacement curve of the structure was obtained. Comparing the load-displacement curve and ultimate load carrying capacity of the structure, it＇s shown that the stability performance of the ellipsoid suspend-dome is much better than that of the single-layer lattice shells. Initial geometrical imperfection will reduce the stability bearing capacity of the structure. Furthermore, the cable arrangement and the prestress level should be optimized because they have influence on the stability performance of the structure.