单层网壳结构风振响应的模态耦合效应分析

基于网壳结栖频谱分布密集、空间相关性强的自身特性，其风致动力响应不仅要考虑多阶模态的贡献，通常还要考虑模态耦合效应。因此，对网壳结构风振响应的模态耦合效应进行研究很有必要。根据模态广义位移协方差矩阵的特性，对Kiewitt6—6型单层球面网壳和三向网格单层柱面网壳结构的模态耦合效应进行了系统的参数分析，在此基础上，给出了网壳结构风振响应的模态耦合效应程度判据。

Study on Modal Coupling Effect of Single Layer Reticulated Shell for Its Wind Induced Vibration

In analysis of wind induced vibration for single-layer reticulated shell structures,it is found that there are some modes in high position of modes order with significant contribution to wind induced response,and the modal coupling effect is also need to be considered owing to the closely located modal frequencies and strong interaction of structural members.According to the characteristic of the modal displacement covariance matrix,parametric analysis of the modal coupling effect for the wind-induced vibration are performed on a Kiewitt 6-6 type of single-layer spherical reticulate shell and a threeway grid single-layer cylindrical reticulate shell.Further more,a criterion for the modal coupling effect is proposed.