Research On Embankment Settlement Caused By High Speed Train

Under the action of dynamic loads, the precise analysis and estimate of railway embanksettlement is a worldwide difficult problem. Any quantitative analysis are rough estimate,there is a big difference comparing actual situation, but the embank settlement analysis ofhigh speed railway is a urgent need to solve the important topic, so the qualitative analysis ofthe railway embank settlement is important. This topic qualitative analysed the relationbetween settlement of railway embank with train weight, train numbers, and train speed. Therelation provided reference for the design of high railway embankment and maintenancingand repairing.This topic qualitative analysed the relationship between the settlement of railwayembank with the train weight, the train number and the train speed, the relation providedreference for the design of high railway embank and maintenancing and repairing. This topicresearch was mainly based on the test observation of the DK854+800railway embanksettlement of the Beijing-shanghai high speed railway, time for six months, once every month.After investigation and analysis to derermine the embankment model and the calculationmethod of the train weight suitable for the research work, and statistical induced the train type,the train number, the train running speed in the research period. Used a computer softwareAnsys to carry on the analysis, calculation of embank settlement values, comparing the actualobservation values, after repeated trial, determined the general Maxwell viscoelasticconstitutive relation of railway embank soil. Changed the train weight, the train number, thetrain running speed into the loading size, the loading action number, the loading frequency onthe railway embank model, though the Ansys finite element analysis software of computer, itcould be concluded that the relation between the railway embank settlementw with the trainweight, the train number, the train running speed.The main achievements were summarized in detail as follows:(1) The detail descriped the current demestic and international relevant research results,cleared up this topic research thinks, grasped the rationality on the results of this topicresearch.(2) For half a year’s observation of railway embank settlement on the place DK854+800of the Beijing-shanghai high speed raiway, taken a settlement observation value, once everymonth, at the same time, investigated and analysed the train type, the train number, the trainrunning speed and so on in this observation period.(3)Comprehensively expound the fundamental state of this experimental study, plantingthe settlement observation pile and relation of the existing horizontal control survey net of high-speed rail and the planted settlement observation piles, selecting the experiment time, thearranging and implement of the experiment program, the experimental result and analysis.(4) Detail introduced various of calculation model of the railway embank and kinds ofrepresentation method of the train loading. Determined the railway embank model and thetrain loading suitable for this topic research. Careful analysed the composition of the railwayembank. Taken the railway embank as the same kind of material composition, this kind ofmaterial had the same physical and mechanical properties, and the important mechanicsparameter were analyzed.(5)In this reseach, we used general Maxwell viscoelastic model to represent the railwayembank soil constitutive relation. Making use of a finite element computer software Ansys,calculated the railway embank settlement. Through compared the embank settlementcalculation value with the practical observation settlement value, after repeated this trial, wedetermined the soil viscoelastic constitutive relation. Applied the different train load on topsurface of viscoelastic railway embank model, and then made the conclusion that train weightwas the main factors which influence the embank settlement, this also was one of the reasonthat high speed train use lightweight and high strength material to reduce train weight.(6)Changed train number into load action time on viscoelastic railway embank model,through the Ansys software analysis, we could get the relationship of embank settlement andloading action time, nearly and had drawed the conclusion that embank settlement and trainnumber was directly proportion, this also was one of reason that railway maintenancingdepartments should regular arrange railway maintenance tasks.(7)Transformed train speed into loading frequency on railway embank model, throughthe computer finite element software Ansys, we considered that railway embank deformationhave no connection with loading frequency, nearly and regarded that the railway embanksettlement has nothing to do with train speed. This also was theory foundation, by it we didnot large-scale reinforce our railway embank in several big train speed increase.