Verification of a Cable Element for Cable Parametric Vibration of One-Cable-Beam System Subject to Harmonic Excitation and Random Excitation

摘要

Nonlinear vibration of cables in cable-stayed bridges is usually studied by either a divide-and-conquer approach in which interaction between local motion of the cables and global motion of the bridge is not considered, or a coupled cable-beam system which can only represent a simple structure with few degrees of freedom. A cable finite element is presented in this paper which can account for in-plane and out-of-plane motions of the cable. A cable-beam system with frequency ratio of 1:1:2 is employed to verify feasibility of the cable element in analysing nonlinear vibration of the stay cable. Vibrations of the coupled cable-beam system under harmonic and random loadings are calculated and compared with the available analytical solutions that have been verified experimentally. The results demonstrate that the cable finite element can capture nonlinear vibration, in particular auto-parametric vibration of stay cables under both loading cases. Consequently it can be applied to practical structures with multiple cables.