异形单层网壳结构体系优化与整体稳定性研究

A Study on Structural System Optimization and Global Stability of Special-Shaped Single-Layer Reticulated Shells

单层网壳是近年来大型场馆的常用结构形式,具有结构轻薄、造型多变的特点。由于单层网壳平面外刚度小,因此其整体稳定性是结构设计需要考虑的关键问题。以实际工程案例为背景,研究了异形单层网壳结构的结构受力机制,对不同结构方案的挠度控制效果和经济指标进行了优化比选。采用ANSYS软件对优化完成后的网壳体系进行模态分析,考虑初始几何缺陷的双重非线性整体稳定分析,并分析了整体稳定性对几何缺陷的敏感度。一系列分析证明:通过加强体系的鲁棒性,可在降低用钢量的情况下,使结构稳定承载力仍满足设计要求。

Single-layer reticulated shell is a common structural form for large stadiums in recent years.It has the characteristics of light structure and changeable shape.Because of the small lateral stiffness of single-layer reticulated shells,the overall stability of single-layer reticulated shells is the key problem that must be considered in structural design.Based on a practical engineering project,this paper studies the mechanism of special-shaped single-layer latticed shell structure,and optimizes the deflection control effect and economic index of different structural schemes.The modal analysis of the optimized reticulated shell system is carried out using software ANSYS.Considering the initial geometric imperfections,the overall stability analysis of the double nonlinear system is carried out,and the sensitivity of the overall stability to the geometric imperfections is analyzed.The result shows by strengthening the system robustness,stable structure bearing capacity still meets the design requirements although steel consumption is reduced.