一种网壳结构基于压力线概念的优化方法

为了提高网壳结构的承载能力,提出一种基于压力线概念的网壳结构优化方法.该方法利用压力线无弯矩的特征,将组成球面和柱面网壳结构轮廓线的圆弧线替代为压力线,使网壳结构在竖向荷载作用下处于压应力状态,从而减小弯曲应力的影响,达到了提高网壳结构承载力的目的.对一个跨度为48m的单层葵花形网壳结构进行几何非线性分析,发现该方法可将极限承载力提高5.48%;进一步对84例不同跨度、不同矢跨比的单双层球面、柱面网壳结构进行分析,结果表明该优化方法正确有效,对矢跨比为1/5左右的单层网壳结构,优化效果较好,最大承载力可提高6.4%.

An Optimum Method for Latticed Shells Based on Concept of Compression Line

To improve the load-carrying capacity of latticed shells,an optimum method based on the concept of compression line is proposed in this paper.Using the character without moment in compression line,the arch line,which forms the contour line of sphere and cylinder latticed shell structures,is substituted by compression line in this method.Then the latticed shell structures are in the state of compression completely,and as a result,it is carried out decreasing the influence of bent stress and increasing the load-carrying capacity.Through the geometrical nonlinear analysis of an single-layer shiwideler latticed shell structure,it is found that the load-carrying capacity can be improved by 5.48%.Furthermore,the results of 84 structural analyses to single-layer or double-layer sphere and cylinder latticed shell structures,show that the optimum method is right and effective.And especially,it is applicable to single-layer latticed shell structure with rise-span ratio 1/5 with the max improvement 6.4% of load-carrying capacity.