Based on the time domain wind loads obtained by wind field simulation, the nonlinear
behaviors of bridge buffeting were investigated by the buffeting analysis method for long-span
bridges. In the investigation, a long-span railway cable-stayed bridge was regarded as an example,
and both structural geometric nonlinearity and aerodynamic nonlinear factors were taken into account
simultaneously. The geometric nonlinear factors include cable sag, beam-column effect and large
structure displacement, and the aerodynamic nonlinear factors are wind incidence angle effect and
self-excited force. The nonlinear kinetic equation of a bridge structure was solved with the double
iteration method. The comparison between linear and nonlinear analysis results shows that the
nonlinear factors can result in a great buffeting response of long-span railway cable-stayed bridges.