【摘要】 网壳结构具有频谱分布密集、振型复杂的动力特性,在对该类结构进行风振响应分析时,通常存在着一些对响应贡献较大的高阶振型,但由于其频率较高而容易被忽略。因此,研究网壳结构风振响应的主要贡献模态分布规律有利于提高结构风振响应计算的精度和效率。本文利用Ritz-POD法,分析了单层球面网壳和单层柱面网壳结构风振响应的主要贡献模态,着重考察了主要贡献模态的自身参振能力,及其与脉动风压空间分布模式之间的关系。在此基础上,初步给出了网壳结构风振响应的主要贡献模态识别准则。更多还原

【Abstract】 In the analysis of wind-induced vibrations of single-layer reticulated shell structures,it is found that there are some contribution-significant modes of high orders to the vibrations.Due to the characteristics of the dense distribution of natural frequencies and the complicated modes of reticulated shell structures,it is necessary to analyze the contribution-significant modes to the windinduced vibrations and develop an efficient criterion for selecting the contribution-significant modes.In order to solve the problem,a Ritz-POD method is presented in this paper,which synthesizes a proper orthogonal decomposition(POD) technique and a direct superposition method for Ritz vectors.Based on the Ritz-POD method,a preliminary criterion for selecting the contribution-significant modes is proposed,which takes into account the vibration-participating ability of each natural mode in an expression of Ritz vectors and the similarity between the mode and the spatial distribution of the fluctuating wind load.更多还原