Strong Wind Span Rigid Frame Continuous Bridge Of The Car - The Bridge Coupled Vibration Analysis

For long-span continuous rigid frame railway bridge, it does not only need to study the vibration problems when trains run through the bridge without wind action, but also study the problems of safety and comfort for the trains under strong winds when the bridge is in the typhoon-prone region. Taking White Horse River Bridge in the line from Wenzhou to Fuzhou as engineering background in this paper, a detailed dynamic simulation calculation and analysis of the dynamic responses of the bridge and train are made under the action of both the wind load and trains load. The contents of this paper are as the following:Firstly, it summarizes the research results of the bridge dynamic analysis under strong wind action and expounds the necessity of analysis of the wind-train-bridge coupling vibration system.Secondly, based on the principles of the bridge structure dynamics, vehicle dynamics and so on, analyses model of the train and bridge dynamic system with strong wind is established.Thirdly, using the numerical simulation theory of random wind field for long-span bridge, numerical simulation of random fluctuating wind field at White Horse River Bridge is made in this paper.Finally, it makes numerical calculation of dynamic response for the bridge and train with wind load and vehicle load acting at the same time. And from four aspects, which are different speeds, different wind speed, different heights of air stopping, different vehicle location, a comparative analysis of the dynamic response of the bridge and vehicle is made.Research shows that: (1) with wind load and train load acting together, response of the transverse vibration mainly depends on the wind load, while the vertical vibration displacement mainly on the factor of dead weight of the train. (2) The vehicles' dynamic response gradually increases with the train speed and wind speed as a whole. (3) Responses of the bridge and the vehicle will be greater when vehicles are at the upwind side of the bridge than at the leeward side as a whole. (4) The index value of the dynamic response has a downward trend as the height of the wind wall increasing. If the air stopping is set with height of 2m or more, the safety and comfort when trains run through will be much better in strong winds.