Resarch On Threshold Of Earthquake Early Warning For High-speed Railways Based On Coupling System Dynamics Simulation

With the rapid development of China High-speed railway, railway mileage is alsogrowing in recent years.Meanwhile, China is a earthquake-prone country,when earthquakeoccurs, it will cause the moving train derailment accident and casualties.So the earthquakeearly warning system for high-speed railways which reduces the railway damage is neededto be established as soon as possible, and the threshold of this system set reasonable or not isdirectly related to the effective and reliability of the system.Firstly, the current situation of the earthquake early warning system for high-speedrailways at home and abroad is introduced,then combined the domestic and internationaldevelopment status with the actual demand for china high-speed railway, the threshold forhigh-speed railway warning system and the principles of train emergency control areanalyzed, it provides theoretical basis for designing the warning system.Some aspects aboutthe threshold are studied as follows:(1)In order to study the safety of moving train when earthquake occurs, atrain-track-bridge coupling system dynamics model is established by finite element software,the calculation results with no earthquake are in good agreement with test results, it verifiesthe reliability of the model, and make mode analysis to the bridge, get the frequencies andmode shapes of the bridge.The track irregularities described as the internal excitation and four typical earthquakeas external excitation are introduced. On the basis of train running safety evaluation index,doing a lot of calculations about train-track-bridge coupling system, get the law of dynamicresponse under different speeds, pier height, earthquake intensity, spectrum.(2) A train-track-roadbed coupling system is established, and the calculation results withno earthquake are in good agreement with test results, it verifies the reliability of the model,and can be used for analysis the dynamic response of the system under earthquake. Doing alot of calculations about train-track-roadbed coupling system, get the law of dynamicresponse under different speeds, earthquake intensity, spectrum.(3) Train-track-bridge-catenary pillar and Train-track-bridge-sound barrier couplingsystem dynamics model is established, and analyze the law of dynamic response underdifferent earthquake intensity, spectrum, respectively.(4) Based on train safety index, catenary current collection performance, structuralstrength, construction clearance, four typical earthquakes are chosen to excite the systems,get the limits of high-speed train excitied by earthquake, obtain the security clearancediagram about earthquake intensity and speed of train. On this basis, we can get thethreshold under different earthquake shocked.(5) Based on the different thresholds, appropriate emergency treatment principle is setup, and there are3levels in total, and takes different measures to control the train accordingto different level.