Abstract:On the basis of comparing the suspension bridges using carbon fiber cables with those bridges using steel cables, the vertical nonlinear vibration feature of suspension bridges was studied, the approximate solutions of suspension bridges’ vertical nonlinear vibration were obtained with Galerkin principle and LP method, and the impact of temperature, amplitude and other factors on the vertical nonlinear vibration of suspension bridges was analyzed. The temperature increment will make the nonlinear vibration frequency of suspension bridges fall, and have larger impact on the timehistories curve of suspension bridges using steel cables. On the contrary, temperature change nearly hasn’t any impact on the timehistories curve of suspension bridges using carbon fiber cables, and amplitude increment will make the nonlinear vibration frequency of suspension bridges increase.