大跨度双层圆柱面网壳结构的优化分析

Optimal Analysis of Large Span Double-layer Barrel Vaults

本文在构造双层圆柱面网壳结构优化的最小造价目标函数的基础上，以网壳结构的矢跨比、网格尺寸、网壳厚度为设计变量，采用０．６１８法与穷举法，编制了计算程序ＶＯＰＤ，通过优化计算，得出了结构在不同屋面体系时，跨度从５０ｍ至１４０ｍ的最优网格尺寸和厚度，并将计算结果归纳为经验公式，以６０ｍ网壳为例研究了网格尺寸、矢跨比、荷载对结构用钢量、造价等的影响；并对三心圆柱面网壳与圆柱面网壳结构在电厂干煤棚中的应用进行了比较分析，得到了一些有价值的结论。

The objective function of minimum cost is established for double-layer barrel vaults taking therise-span ratio, grid size and vault thickness as design variables. Based on the methods of exhaustionand 0. 618, the computing program VOPD has been developed. Concerning double-layer barrelvaults of 50-meter to 140-meter spans, the optimal grid size and vault thickness have been obtainedfor different systems of roof materials with different spans. Empirical formulas are deduced from theresults. In addition, the steel consumption and cost of structures of a double-layer barrel vault with60-meter span is discussed on the conditions of different grid sizes, rise-span ratios and loads. Theapplication of barrel vaults and three-center barrel vaults to coal storage has been compared as well.