以动力稳定为目标的空间结构等效静力风荷载

Dynamic-instability-based Equivalent Static Wind Loads on Spatial Structures

摘要:

采用基于位移或内力响应等效的等效静力风荷载进行大跨空间结构的稳定分析并不十分合理.以动力稳定为目标的等效静力风荷载将使大跨空间结构的设计能够满足稳定性设计的要求.提出大跨空间结构以动力稳定为目标的等效静力风荷载的概念和初步方法,并应用于单层柱面网壳的稳定性分析.通过风洞试验获得柱面网壳表面的非定常气动力,利用BudianskyRoth准则分析该网壳的动力稳定性,得到以动力稳定为目标的等效静力风荷载.通过对比以动力稳定为目标和基于位移等效的等效静力风荷载下的稳定性分析结果,表明大跨空间结构进行稳定性分析时有必要采用以动力稳定为目标的等效静力风荷载来考虑风荷载作用.

关键词:空间结构; 以动力稳定为目标; 等效静力风荷载; 风洞试验; BudianskyRoth准则

Abstract:

The paper presents the concept of dynamic-instability-based equivalent static wind loads and the elementary method to obtain them and then the method is applied to studying the stability of a single-layer reticulated cylindrical shell.The unsteady aerodynamic forces on the shell are obtained from the wind tunnel test,the dynamic instability of the shell are investigated by the Budiansky-Roth criterion,and then the dynamic-instability-based equivalent static wind loads on the shell are gained.Comparison of stability of the shell under two kinds of equivalent static wind loads,the dynamic-instability-based and the displacement-based,shows that it’s necessary to adopt the dynamic-instability-based equivalent static wind loads to consider the wind actions in the stability analysis of large-span spatial structures.

Key words:spatial structures; dynamic-instability-based; equivalent static wind loads; wind tunnel test; Budiansky-Roth criterion