| With the rapid development of high-speed railway,wheel rail impact between vehicles and high-speed turnout has become an important research problem in the field of high-speed railway.When the train quickly passes through the switch,the wheel will have a violent dynamic impact on the switch rail,which will not only make the switch produce wear,fatigue and other injuries and diseases,increase the workload of maintenance and maintenance,and easily cause the derailment accident of vehicles in the switch area,seriously affecting the safety of driving.At the same time,there are many kinds of switch parts,there are some combination rail parts,take high-speed switch switch as an example,because the lower support modes of the sharp rail(movable rail)and the basic rail(fixed rail)are different,coupled with the weak vertical constraint relationship between them,under the action of wheel load,two rail will inevitably produce vertical relative motion.When the wheel-rail contact relationship is affected,the dynamic characteristics of the vehicle-switch vertical coupling system are also affected.Based on the analysis of the existing research literature,the current research work on the coupling dynamics of locomotive turnout mostly considers the combined rail as a whole,ignoring the influence of its relative motion.Therefore,in this paper,the relative motion of the combination rail of the sharp rail and the basic rail in the high-speed switch is fully considered,and the vertical coupling dynamics model of the vehicle-switch is established.Based on this model,the simulation analysis system is developed and the model is verified,and the wheel-rail dynamic characteristics of the vehicle-switch without considering the relative motion of the combination rail are compared.The influence factors of vehicle-switch vertical dynamic characteristics are analyzed.The specific work and conclusions of this paper are as follows:1.Construct the vehicle-switch vertical coupling dynamics model,develop the simulation analysis system and verify the model.By comparing with the results of statics,the vehicle submodel and the switch submodel are verified respectively.The simulation results agree with the statics results,which verifies the correctness of the two submodels.The correctness of the vertical coupling dynamics model of vehicle-switch is verified by comparing with the results of the field test of load reduction rate,which provides a simulation analysis tool for the subsequent research work.2.Starting from three aspects of wheel-rail vibration displacement,wheel-rail dynamic force and wheel-rail vibration acceleration,the dynamic characteristics of vehicle-switch wheel and rail without considering the relative motion of combined rail parts were compared and analyzed.The analysis results show that the relative motion of the sharp rail and the basic rail has a significant influence on the dynamic characteristics of the wheel-rail of the vehicle-switch,which indicates that the relative motion of the combined rail in the vertical coupling dynamic analysis model of the vehicle-switch can more accurately reflect the real dynamic characteristics of the vehicle passing the switch.3.General simulation analysis system was used to analyze the influence law of vehicle speed,vehicle profile and sharp rail reduction on the vertical dynamic characteristics of vehicle-switch.With the increase of vehicle speed,the wheel-rail vibration acceleration and wheel-rail force increase,and the wheel-load transition range shrinks.The acceleration of rail vibration,the overall wheel-rail force and the transition range of wheel-load increase significantly in the process of profile change caused by the increase of driving distance.With the increase of the reduction value of the sharp rail,the vibration acceleration of the straight sharp rail and each wheelset increases,the wheel-rail force increases,and the range of wheel-load transition Narrows. |
