The Dynamic Characteristics Of Ballasted Track With Low Filled Height Bed

China's urbanization construction process needs to speed up a large number of urban rail transport project .As the track structure that on the ground is being used more and more in the urban rail construction ,and the frequency of the urban railway train increases, it requires higher quality of the roadbed and the rail track structure .In the new urban areas, the urban-rural junction, in order to save the investment,accelerate the construction speed of the urban rail transportation system .We can use low roadbed in the ground line to improve the urban traffic jams.Ballasted track is a complex construction , Its material shows different characteristic and receives complex strength that is intensively stochastic and complex. The road bed receives the loads from upper structure and pass them down to the ground, if the height of the road bed is very low, the stress acted on the ground without fully diffused. It is necessary to have a mechanical academic analysis to achieve a good design, examine and improve on the track structure.In order to make sure the vertical load transfers through wheel-track in coordinate situation, We use ANSYS to build an three-dimensional rail and roadbed integration structure model refers to Peking urban railway that on the ground with ballasted track. carefully consider all the tiny part of the rail and the road bad structure, calculate all the results of the rail structure's performance on the basis of rail track dynamic theory and roadbed theory , summarize the vertical load transmission law of the rail structure, and the influence of the rail structure when the parameter of the model changes.