环向波浪形网壳结构形态生成与受力性能分析

Configuration generation and mechanical properties analysis of circular-wave reticulated shells

以环向波浪形网壳结构为分析对象,对其形态生成方法进行介绍,并对选用该类形态的凯威特网壳进行力学性能分析。由环向波浪曲面几何特征提取几何参数并构建型值点阵,通过B样条曲面插值与网格映射生成网壳结构。将波浪形网壳形态基本几何参数与脊线调节参数选为设计变量,利用ANSYS通用有限元软件,计算结构的力学性能指标。结果表明:结构高跨比对结构的体型规模影响较大,宜取1/4~1/2;底部内外半径差表征波浪的横向波幅,其值增大有利于改善结构整体受力性能;底部内外高差系数表征波浪的竖向波幅,宜取0.3~0.4;脊线调节参数对结构水平支反力等力学性能指标具有较大影响;环向波浪形网壳选型时应优先确定结构高跨比等基本几何参数,再确定脊线调节参数。

The configuration generation technique of circular-wave reticulated shell was introduced. The mechanical properties of circular-wave Kiewitt reticulated shell were analyzed. The geometrical parameters extracted from the characteristic of the circular-wave surface were used to build data points. Then B-splines interpolation and reflection meshing method were implemented to generate the reticulated shell. The basic geometric parameters and adjustment parameters of ridge-lines of the circular-wave reticulated shell were chosen as the design variables. The mechanical properties indexes of the reticulated shells were calculated with ANSYS software package. The results show that heightto-span ratio determines the size of structure,whose value is suggested to be 1 /4-1 /2. The radius difference between inner and outer circles at the bottom can describe the horizontal amplitude of wave,the increase of whose value can improve the structural mechanical properties. The value of height difference coefficient between inner and outer circles at the bottom is suggested to be 0. 3-0. 4,which describes the vertical amplitude of wave. The adjustment parameters of ridge-lines have great influence on some mechanical property indexes such as horizontal reactions. Therefore,for the configuration determination of circular-wave reticulated shell,the basic geometric parameters such as the height-tospan ratio should be given priority to be determined,and then the adjustment parameters of ridge-lines can be determined.