Study On Efficient Method For Dynamic Analysis Of Train-Track-Bridge Coupled System Based On Transfer Matrix Method And Model Condensation Technology

With the rapid development of railway,the scale of train-trackbridge coupled system(TTBS)is increasing,and the complexity is gradually improved,which requires higher computational efficiency.In order to reduce the number of degrees of freedom of TTBS and improve the computational efficiency of dynamic analysis,the following research work has been carried out in this thesis:Firstly,Taking advantage of the periodic characteristics of the track structure,the train-track coupling dynamic analysis method based on the transfer matrix method(TMM)is proposed.In this method,the repetitive parts of the track are divided into several cells,and the overall transfer model is established through its transfer relationship to realize the transfer solution of the response in the overall structure.A moving track technique is introduced into the TMM to calculate the long track based on a finite number of cells.Taking the train passing through track structure as an example,the accuracy and efficiency of the method are verified by comparing the calculation results and time-consuming of TMM and direct stiffness method(DSM).Secondly,based on TMM and model condensation technology(MCT),an adaptive multi-scale model and a dynamic transfer matrix method(DTMM)is proposed.The whole structure is divided into several substructures,and the substructures in the load affected area are further divided into fine cells to accurately solve the local vibration.The remaining substructures directly establish super element cells based on MCT to reduce the internal degrees of freedom.Then,the DTMM is used to dynamically update the cell arrangement information according to the load position in the process of dynamic solution,carry out cell adaptive assembly,and establish an adaptive multi-scale transfer model to realize the synchronous and efficient transfer solution of overall and local dynamic response.Taking moving load passing through the truncation model as an example,the accuracy and efficiency of this method are verified by comparing the calculation results and the time-consuming of three methods.Finally,on the basis of the above work,a hybrid model approach(HMA)based on TMM and MCT is proposed.In this method,the dynamic equations of track and bridge subsystems,and its equations of motion are established by multi-rigid-body dynamics(MBM),TMM combined with moving track technique,and DTMM based on the adaptive multi-scale model,respectively.The three subsystems are coupled by the interaction forces(wheel-track force and track-bridge force)between the train,track and bridge.Taking CRH-2 EMU passing through a simply supported steel truss bridge as an example,the calculation results and time-consuming of the three methods are compared.The results show that this method can realize the synchronous,accurate and efficient solution of local highfrequency vibration response of track structure and overall and local vibration response of bridge structure.