风动力效应对斜拉网壳结构承载性能的影响分析

Analysis of influence of wind-induced dynamic effect on bearing performance of cable-stayed shell structure

为将风致响应分析与承载安全性能评估结合起来,引入了一种简化的极限承载能力风振系数。通过计算出风荷载动力效应下与静风作用下结构整体极限承载能力的比值,较方便地实现了考虑风动力效应的斜拉网壳结构承载安全评估。然后讨论了网格厚度、荷载组合比例值和预应力水平等参数对简化风振系数的影响规律。结果表明:结构刚度越柔,屋面质量越轻,预应力水平越高,风动力效应的影响越显著一些。

A simplified wind vibration factor for ultimate bearing capacity was introduced to link the wind-induced response analysis and bearing safety performance evaluation. By calculating the ratio of ultimate load capacity of the integral structure under dynamic wind effect and under static wind load, the safety evalua- tion of the bearing performance considering dynamic wind effect can be realized conveniently. Then the laws of influence of shell thickness,loads combination ratio and prestressing level on the simplified wind vibration factor were discussed. The results show that the lower the structure stiffness is, the lighter the roof mass is, the higher the prestressing level is, and the stronger the influence of dynamic effect is.