The Analysis Of Dynamic Models And Parameters On High Speed Train-ballastless Track-bridge Coupled System

High-speed train driving on the elevated bridges with the ballastless track causes thevibrations of the structures of tracks and bridges which will influence the vibrations of thetrains in turn. The vibrations become more and more obvious with train speed and vehicleload increasing continuously. The high speed train-ballastless track-bridge coupled systemis put forward based on the promotion and application of high speed trains, ballastlesstracks and elevated bridges in China railway industry. The finite element analysis modeland the modal analysis model are established and solved by implicit integration methodand explicit integration method respectively. The influence of the change of some dynamicparameters and several track irregularities existing simultaneously on vehicle safety,vehicle ride comfort and bridge dynamic safety is studied.According to the interaction characteristics of high speed train, slab ballastless trackand bridge, a versatile finite element method is employed to analysis the dynamicsproperties of the train-track-bridge coupled system. Two kinds of finite element model areestablished, one of which is train-rail finite element and the other is slab ballastlesstrack-bridge finite element. Hamilton principle is applied to solve the vibration equations.Then the system equations assembled by the general method can be solved by somenumerical methods. The correctness of this method is verified through a numericalexample. No matter how complex the structures over the bridges, the track-bridge finiteelement and the whole vibration equations can always be obtained which verified theversatility of this method.The modal analysis model of high speed train-long sleeper buried ballastlesstrack-bridge coupled system is established. The interaction force between wheel and railcan be defined by Hertz nonlinear elastic contact theory. A new explicit integration method is used to obtain the numerical results of the system equations. Furthermore, the influenceof the dynamic parameters, such as speed and suspension parameters of train, trackirregularity, connection parameters between track and bridge and so on, on the dynamicperformance of the system is studied.The case of several track irregularities existing simultaneously is considered when thedynamic problems of the train-track-bridge coupled system are solved. The results showthat the influence of several track irregularities existing simultaneously on the systemdynamic performance is not a simple superposition or subtraction of the influence of thesingle track irregularity. Therefore the complex mechanism should be studied further todetermine the types of track irregularity and the role of action.The research work in this paper can provide strong theoretical basis to the structuraldesign and construction of train, track and bridge.