组合型扁扭网壳结构分析

Analysis of combined-type flat twist latticed shell

组合型扁扭网壳主要用于大空间屋盖,这种网壳具有自重轻、刚度好、节约钢材等优点。目前,组合型扁扭网壳在国内的研究和应用还相对较少。采用连续化的数学模型,首先给出了网壳的内力与位移的关系,以及简要地介绍了拉格朗日乘子法。然后对组合型扁扭网壳的静力与动力特性采用能量变分原理进行分析,采用拉格朗日乘子对约束条件和位移函数进行了处理,得到了用于变分分析的无约束泛函。通过一个算例阐述了该方法的应用,供结构初步设计参考。

Combined-type flat twist latticed shell especially is used in large spatial roofs,which has the features of light weight,high stiffness and saving steel. At present,the research and application of this combined-type flat latticed shell are still not widespread. The mathematical model of an equivalant contimun was proposed. Firstly,the relationship of internal force and displacement of this latticed shell was deduced,and the lagrange multiplier method was briefly introduced. Then the static and dynamical characteristics of combined-type flat twist latticed shell were analyzed by the energy variational principle,and the treatment of the constraint conditions and the displacement function gives an unconstrained variational analytic function by adopting lagrange multipliers. Finally,a numerical example was given to illustrate the application of this method,which can be used in the preliminary design of structures.