Study On Temperature Action And Temperature Deformation Of Steel Box Girder Of High Speed Maglev

The high-speed maglev system has high running speed and strict requirements for the suspension control gap between the train and the track.The post construction deformation of the track beam structure has an important impact on the safety and stable operation of the train.Because the steel panel of steel box girder directly receives solar radiation,and the thermal conductivity of steel is better than that of concrete,the temperature effect is bound to be more significant.Therefore,the research on the temperature effect and temperature deformation of steel box girder of highspeed maglev track can provide important technical support for reasonable structural design and safe operation of the line.The main research contents of this paper are as follows:(1)The 3D thermodynamic model of steel box girder under solar temperature field is established by using the multi-physical field finite element software.The correctness of boundary conditions,calculation parameters and model are verified by comparing with the measured data.(2)Based on the statistical method of Generalized Pareto Distribution(GPD),the extreme value analysis model of meteorological elements is established.The parameter standard values of atmospheric temperature and solar radiation under different return periods are obtained.According to the daily temperature extreme value data and daily average solar radiation,the conversion formulas of hourly temperature and hourly solar radiation intensity are put forward.(3)The overall 3D thermodynamic model of high-speed maglev is established by using multi-physical field finite element software.Various meteorological data from Qingdao,Guangzhou and Nanjing are processed and input into the model as boundary conditions for calculation.The temperature time history,deformation and stress of the high-speed maglev track steel beam are analyzed,and the temperature gradient model is proposed.(4)The effects of different structural forms,trends,regions,solar radiation absorptivity,wind speed and functional parts on the solar temperature effect of the high-speed maglev track steel beam are analyzed,which can provide a reference for controlling the temperature deformation of track beam.There are 85 figures,8 tables and 74 references.