Temperature Effect And Mechanical Analysis Of Low-Speed Maglev Track Structure

In the past half century, many researches have been conducted on the low-speed maglev transit technology, but its engineering applications are rare, relevant technical standards has not yet formed in the word. Domestic scholars are formulating low-speed maglev technology standards combined with the construction experience of low-speed maglev test line and rail transit technology standards. The basic research of low-speed maglev orbit is few, the design and construction of orbit lack the adequate theoretical reference and basic data. For example, the current design of viaduct girder rarely considered the temperature effect. The cognition of low-speed maglev track panel structure deformation and its dynamic response were unclear. The theoretical basis of optimization design for track panel structure still lack the theoretical basis.Against this background, this paper built a detailed finite element model of low-speed maglev track structure. Firstly, temperature effect of the low-speed maglev girder under different temperature difference was analyzed. Secondly, the static analysis of the track structure of different low-speed maglev train loads was analyzed. Finally, low-speed maglev train and track coupled vibration analysis model was built and obtained the dynamic response of low-speed maglev track.On the basis of the analysis of low-speed maglev orbit, the finite element model of low-speed maglev orbit was built, then, temperature deformation of the girder caused by various temperature differences between top surface and under surface, or one side and the other side, were calculated by the thermal-structural coupling analysis method, which are compared with the limits for maglev transportation. Calculated results show that temperature of the girder distributes linearly along the direction of temperature loads, and the temperature gradient increases with the temperature difference.According the recommended standard of high-speed maglev transport, maximum deflection of the20-m girder for low-speed maglev transit under those conditions in this paper, will exceed the limits of temperature deformation when the temperature difference is greater than20℃. Consequently, it is necessary to analyze temperature deformation of the concrete girder for low-speed maglev transit based on the real temperature conditions in the practical engineering。The static analysis model of low-speed maglev track with connecting bars was built. The stress and deformation of the track under three kinds of low-speed maglev train loads was calculated, according to the relevant design standards, the force and deformation of the track was preliminary assessed. Besides, the analysis model of low-speed maglev train track structure coupled vibration was built and the track panel dynamic response of different driving speed of low-speed maglev was alculated and analyzed. The paper obtainted the basic characteristics of track panel dynamic response and its change law with maglev speed and stiffness of the rubber pad under the sleeper. The results of the paper provided theoretical basis and reference for engineering design and construction of the low-speed maglev track.