Influences Of The Differential Settlement On Track Vibration Of Subgrade-bridge Transition Section Of High-speed Railway

The subgrade-bridge transition section of high-speed railway has always been the hot spots,key points and difficult problems of research,especially with the increasing and continuous development of the speed of railway,there’re higher demands and requirements for both the related theories and engineering technology.So it’s definitely necessary to do studies and researches on it,just like this paper.Based on the engeering background of Wuhan-Guangzhou high-speed passenger dedicated line,considering the differential settlement of the transition section,the impact vibrition response of the track to the train when it gets off the bridge is analysed and the influence of five different factors is also included in this paper.The details about the research,such as puspose,methods,results and conclusions,are all described as follows.Firstly,the paper has a brief introduction of this research,including the background,the current situation at home and abroad,the siginificance,the main contents and the route.Then it goes straight to the point,a simplified model of the transition section is establied and analysed,in which the rail under the moving load of train is recognized as a bending vibration model of the simply supported beam under a moving load.We get what we want,sure it’s the vibration equation and the solution of the differential eqution by using the mode superposition method.After that,we introduce something about the track irregularity and the expression of trail load is obtained.Taking CRH2 C EMU as an example,the train load at different speeds is calculated and simulated based on Matlab,so we get the corresponding train load time history curves and do FFT analysis to them.Secondly,combining the train load and the solution of the eqution,the corresponding dynamic response is obtained by mode superposition method.Taking various factors under careful consideration,including different settlements,different speeds of moving load,different lengths of track,different impact locations and different impact angles,we solve the dynamic responses and get the theoretical solutions by Matlab programming.Then,we get the displacement,velocity and acceleration reponse of track vibration,and the reponse rules of track vibration under different factors are analyzed in detail.Finally,we use APDL of Ansys software to get the the finite element numerical solutions.In that case,all results are carried out,and a series of displacement nephogram,time history curves and animations of track vibration are obtained simultaneously.Then conclusions are obtained by comparative analysis,which includes not only the solutions bsed on Matlab and APDL,but also the solutions of various factors.Luckily,this paper is finished and I have to say we are done with all the tasks.