复杂形体大跨叉筒网壳结构的风场风载模拟

风荷载是大跨度网壳结构设计的控制荷载。但网壳结构造型日趋复杂,致使结构表面的风压和风载体形系数的确定愈加困难。本文针对典型的复杂体型多向叉筒网壳结构,采用数值风洞技术研究结构表面的风压分布和风载体型系数,分析交叉柱筒的数量、交叉柱筒曲率、矢高比、下部开敞或封闭等不同工况对风压分布和风载体型系数的影响。根据节点风载体型系数划分子区域,利用加权平均法计算各子区域的平均风载体型系数,进而为大跨度复杂体型网壳结构的抗风设计提供依据。

SIMULATION OF WIND FIELDS AND WIND PRESSURES FOR LONG-SPAN SPACE STRUCTURES WITH COMPLICATED SHAPE

The wind action is one of the most important loads acting on long-span space structures. However, it is rather difficult to get the relative wind pressure distribution on a structural surface with a complicated shape. The numerical simulation technique is introduced to study the wind flow field around a space groined latticed vault (SGLV), the relative wind pressure distribution and the wind-induced vibration response of the SGLV. The influence caused by such parameters as the number of cylindrical sectors, the structural curvature and the ratio of rise to span on the relative wind pressure distribution for the open or closed SGLV is studied. Furthermore, the local average relative wind pressures on sub-areas based on the weighted average method are given.