Optimization Research On The Vehicle-track Vertical Coupling Interaction Of High Speed Railway

With the development of high-speed and heavy railways,the interaction between the wheels and rail is increasing,and the vibration between the vehicle and the track system is continuously increasing,so it is very vital for the whole vehicle-track coupling system to deepen the study of high frequency vibration response between wheel and rail system.Referring to the existing research achievements at home and abroad,the modeling and calculation methods of the traditional vehicle-track vertical coupling system are optimized.The main works is as follows:(1)A new model of rail-sub rail track structure dynamic analysis is established.Based on the finite element method,the rail is regarded as the infinite continuous beam with elastic discrete point support,and is separate from sub-rail track structure in this paper.Compared with the traditional modal analysis,there are some advantages for this model in obtaining high frequency vibration response and iterative convergence,and it can deal with more non-ideal engineering situation with various kinds of sub-rail track structure.(2)Deduce the constraint condition processing mode between the rail system and the sub-rail track structure system.The track slab subsystem is modeled separately from the rail subsystem,but the two subsystems need to satisfy the geometry compatibility condition and the static equilibrium condition.The rail apply force on the track slab through the rail pad,but the track slab,in the form of force displacement and force velocity,is applied to the rail system by the rail pad.(3)Based on the Hertz nonlinear elastic contact theory,complete a vehicle-track vertical coupling dynamic analysis program.Based on the Hertz nonlinear elastic contact theory,the vibration differential equation and convergence criterion of the vehicle-track vertical coupling system are established,in the final,complete the vehicle-track vertical coupling dynamic analysis program VTVCD using Newmark-?,which can be applied to much more actual conditions of the project,for such as,the track slab,subgrade,bridge and so on.(4)Do the research on the influence of track geometry irregularity and track stiffness irregularity on the whole vehicle-track dynamic response.In this paper,the dynamic responses of three excitation sources to the vehicle-track coupling are compared and analyzed,the track geometry irregularity,the track stiffness irregularity and the both.So draw a conclusion that in the section with good track stiffness,the track geometry irregularity is the main excitation source of the vehicle-track coupling system,however,the vibration response of rails can also be affected by the track stiffness irregularity in a certain extent.