Identification of natural modes with significant contributions to wind-induced vibration of single-layer reticulated shell

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.