Effect of wheel flats on the high-speed wheel-rail contact behavior

Wheel flats often occur when the wheel locks and slides along the rail during the operation of high-speed train. Wheel flats would generate abnormal wheel-rail impact force and aggravate the fatigue damage of the vehicles and tracks. In order to investigate the influence of wheel flats on the high-speed wheel-rail contact behavior, a high-speed wheel-rail coupling dynamic model that addresses wheel flats was set up, where the geometrical shapes and contact mechanisms of the newly formed and worn wheel flats were modelled. Through the numerical analysis, a detailed investigation into the dynamic response of high-speed railway vehicles excited by the newly formed and worn wheel flats was carried out, with a focus on analyzing the effects of wheel flats on the wheel-rail normal force and vertical vibration acceleration of the wheelsets. A systematic investigation was performed on the influence of train speed, wavelength and depth of wheel flats on the wheel-rail contact behavior under high speed. Finally, a calculation method to define the wheel flat repair for high-speed wheels was presented. ©, 2015, Science Press. All right reserved.