| With the development of railway transportation to high-speed,heavy-duty and high-capacity modes,railway traffic safety is particularly important.For the newly repaired and overhauled railway lines,there are problems that the ballast bed particles are loose,the lateral resistance is weak,and the stability of the train is poor.Through the dynamic stability of the track dynamic stabilizer,the lateral resistance of the track bed to the sleeper and the overall stability of the train operation can be fundamentally improved.The stabilize unit is a key component in the operation of the track dynamic stabilizer.The operating parameters of the stabilize unit,the energy transfer efficiency between the components of each subsystem,and the fatigue life of the walking wheel directly affect the improvement of the efficiency of the dynamic stability and the improvement of the work quality.The dynamic stabilizer and the track are composed of a large-scale nonlinear system,and there are still many difficulties in systematic research.Therefore,this paper chooses the system of the stabilize unit and track composition as the research object.Based on concentrated parameter method,the rigid-flexible coupling theory and the fatigue life analysis theory,the lateral dynamic characteristics,the energy transfer efficiency between the components under the vertical and horizontal coupling and the fatigue life of the walking wheel are systematically studied.Through the analysis of the operation principle of the stabilize unit,the concentrated parameter method is used to establish the multi-rigid lateral dynamic model of the stabilize unit-track system.The effects of different track conditions and operating parameters on the lateral displacement and velocity changes of the sleepers during operation were analyzed.Combined with the requirements of the railway standard for the lateral resistance of the ballasted track,the optimal excitation frequency corresponding to the research conditions in this paper is 30~33Hz.The finite element model of rail-sleeper finite element model is established based on the engineering structure.The calculation of the elastic deformation of the rail during steady operation is carried out.It is concluded that the elastic deformation of the rail is much larger than that of the sleeper during the steady operation.It is pointed out that the elastic deformation of the rail mainly comes from the rail during stable operation.In the ADAMS,a multi-rigid dynamic model of the stabilizer-track system is established,and then the rigid-flexible coupled dynamics model of the system with flexible rail is established.The effects of different operating parameters on the transfer efficiency between the stabilize unit,rail and sleeper were studied.The conclusion is as follows: When the vertical static pressure is constant,the energy transfer efficiency between the stabilize unit and the rail gradually decreases with the increase of the excitation frequency;when the excitation frequency is constant,it increases with the vertical static pressure.When the vertical static pressure is 60,120,180 kN,the energy transfer efficiency between the rail and the sleeper increases first and then decreases with the increase of the excitation frequency.The highest efficiency is 42.6%,60.2% and 66.6% for stress vibration frequencies of 37 Hz,33Hz and 29 Hz.When the vertical pressure is 240 kN,it decreases with the increase of the excitation frequency.When the excitation frequency is 21 Hz,the efficiency is up to 82.7%.The total energy transfer efficiency of the system increases as the vertical static pressure increases as the excitation frequency remains constant.When the vertical static pressure is constant,the total energy transfer efficiency of the system gradually decreases with the increase of the excitation frequency.Through the dynamic simulation of the rigid-flexible coupling model,the lateral and vertical load values of the walking wheel under different working conditions are obtained.According to the operation principle,the fatigue life analysis model of the running wheel system is established.Based on the operating principle,the fatigue life analysis model of the walkway system was established.In the Fatigue Tool,the fatigue life of the walking wheel and the overall fatigue life of the model system under different stable operating parameters were analyzed from the aspects of fatigue life,fatigue safety factor and fatigue sensitivity.The results show that the fatigue life cycle number of the walking wheel and the model system decreases with the increase of the vertical static pressure when the excitation frequency of the stabilize unit is constant.When the vertical static pressure of the stabilize unit is constant,With the increase of the excitation frequency,the number of fatigue life cycles of the walking wheel and the model system is gradually reduced. |
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