Modeling And Analysis Of Heavy-duty Truck-track Coupling Dynamics

In this paper,based on the multi-body dynamics and finite element theory,the vehicle-track-bridge coupling model had been established to be analyzed for the influence of different working conditions and track parameter on the system.The heavy haul railway truck-subgrade-ground finite element model was established and it's stress forecast simulation optimization has been discussed.Firstly,based on SIMPACK and the heavy truck structure,the wheel-rail contact model was established by Hertz elastic contact and Kallker nonlinear rolling theory,which considered normal force,creep force between the wheel and rail.After considering the nonlinearity characters in truck,the truck dynamics model was established and the driving stability of the truck was analyzed.Secondly,the three-dimensional finite element model of track and 32m simply-supported beam bridge were established.The natural frequency and vibration mode were obtained by modal analysis.After the track and bridge superelements were achieved and the flexible track configuration program was written,the vehicle-track-bridge coupling model had been established.The simulation samples of track irregularity in a time domain were achieved and the reliability of the model is verified by the experimental results.Again,based on the coupling model,the dynamic response of the empty and heavy hual truck which were passing bridge has been carried out at different speeds.The reponse was evaluated well with relative code.The safety of the empty truck is lower than the heavy hual.The influence of the change of bridge length,track irregularity and track stiffness on system were analysed and the range of the track stiffness's value was proposed.Finally,Considering the effect of subgrade superstructure,the subgrade load system model with it's elasto-plastic material was established to finish the finite element simulation analysis of the influence characteristics of subgrade stress under the load of truck.The dynamic stress and it's attenuation in subgrade were computed and their effect with the different axle load,ballast bed's thickness and elastic modulus,surface layer of subgrade bed's thickness and elastic modulus was also analysised.