Research On Fatigue Strength Of Rubber Joint Of High-Speed Train

Rotational arm location style is used to locate the axle-box of high-speed train increasingly. The axle-box and rotational arm are linked together, and connected to the bogie frame through the rubber joint in the end. Axle-box location device with rotational arm is characterized by: no-wear; convenient to maintain; can achieve different vertical and horizontal positioning stiffness, and can curb the hunting movement effectively, meet the horizontal movement performance requirements of vehicle. Rubber joint can provide right longitudinal and horizontal stiffness, However, because of the mechanical behavior of rubber elastic element is very complex, the match of design parameters and structure performance is very difficult, in fact, the design based on conventional analysis and calculation is very difficult to meet the safety requirements of high-speed train .In this paper, integrated with the latest results of rubber elastic element, type, structure, performance and affecting factors of rubber joint are summarized, the stiffness and fatigue strength characteristics are analyzed in detail by multi-body dynamic simulation, finite element analysis and fatigue analysis. Constitutive model which is suitable to carbon-filled rubber material is adopted, the material parameters which are used for stiffness analysis and prediction of life expectancy is obtained. Radial, axial and torsional stiffness characteristics are obtained, the influences of pre-displacement, thickness of rubber, structure of out-metal of rubber joint on the stiffness of the three deformation are analyzed .The stiffness of rubber joint is input to dynamics simulation software SIMPACK, the simulation result shows the affecting regulations of stiffness on vehicle critical speed, stability index and wheel-rail wear power. The finite element model of the rubber joint is imported to n-soft software to predict fatigue life, weak point of rubber joint is obtained, the influences of pre-displacement, the thickness of rubber, the structure of out-metal of rubber joint on fatigue life of rubber joint are analyzed.The main contribution of this paper lies in that integrating the research methods of vehicle system dynamics, finite element analysis and fatigue strength of rubber materials, the influence of the basic parameters of rubber joint on the dynamic performance and fatigue life is studied symmetrically. Theoretical basis is provided to the design of location rubber joint of axle-box.