Nonlinear Vibrations Of Stayed Cables Of Cable-stayed Bridge

Cable-stayed bridges have been widely used in modern bridge constructions. It is superior to any other kinds of bridges with respect to span and economical efficiency and so on. Nevertheless, the vibration especially nonlinear vibration of stay cables has been always a key point and difficult point. The nonlinear vibration of stay cables may cause damage and corrosion of stay cables, and even can endanger the working life of cable-stayed bridges.This article mainly talking about the nonlinear vibration of stay cables. In the first, it discuss the factors that influence on nonlinearity of stay cables such as sag effect, bending moment and axial force effect and large displacement effect, and it researchs effective methods to deal with these effect. Then, this paper talks about the mechanism of the nonlinear vibration, and making models of SDOF nonlinear free vibration and TDOF nonlinear rain-wind-induced vibration. Some equations are built which then are simplified by using mathematical, elastic-plastic mechanics knowledge and so on. For the single-mode free vibration , numerical analysis is gived, and some comparison is obtained by examples of considering bending rigidity of stay cables whether or not. at last some useful conclusions are acquired. When discussing about nonlinear rain-wind-induced vibration, it mainly contains cause of formation, mechanism, characteristic, mode, factor, equations and relevant solution of the vibration.In the last part of the paper, coupled vibration of cables and bridge are discussed by building a TDOF model that contains a cable and a deck mass block. In the example, it simulates damage of cables by change rigidity and researches the effect on nonlinear dynamic and static characteristic of the built model. Some conclusions are obtained at last. In this paper, several simulation methods of stay cables and some vibrations reducing measures are discussed.