LAUSR

Abstract A novel modeling method is proposed and used to overcome the in-plane eigenproblem of cable-stayed bridges (CSBs). The modeling method is divided into three steps. Firstly, according to the multi-tower configuration and mechanical characteristics of the CSB, the entire CSB is divided into multiple substructures, namely, a single-tower CSB. Secondly, the substructure is treated by a novel method to make it be a chain-like system and the dynamic triple-beam model with discrete springs is developed. The eigenproblem of the substructure is solved by transfer matrix method (TMM). Then, the entire multi-beam model with discrete springs of the CSB can be obtained by assembling all substructures with consideration of the matching conditions, and the eigenvalue and eigenvector of the CSB can be solved by TMM considering the boundary conditions. The above method is demonstrated by four examples of two kinds of CSBs, namely, semi-floating and rigid-frame CSBs, which are also verified by finite element method (FEM). The proposed model and solution method can be used to calculate the natural frequency and mode shape and evaluate the vertical bending stiffness of the CSB.