Nonlinear dynamic responses of long-span suspension bridge with the action of both running train and cross wind

A framework for performing dynamic responses of long-span suspension bridge under the action of both running train and cross wind is presented, while taking the geometric nonlinearities of structure into account. The nonlinear dynamic equations of the coupled train-bridge-wind system are established, and solved with the Newmark numerical integration and direct interactive method, a corresponding computer code is written, too. The proposed framework is then applied to a schemed suspension bridge with the main span of 1120 m. The time histories of the bridge responses are simulated, when the train passing through with wind acting on both train and bridge. The results demonstrate that the geometric nonlinearities' effect is obviously. Both train-speed and wind velocity have great influence on the maximum deflection of the bridge.