Analysis Of The Influence Factors Of The Wheel-Rail Wear On The Curves Of Heavy Haul Railway

With the booming development of economy and the increase of railway transport volume year by year heavy haul railway transportation has become the direction of railway freight transport development in China. However, because of the increase of the vehicle speed and axle load, it causes that on one hand, the destructive effects of train dynamical load on the rails are getting more serious; on the other hand, track alignment parameters and wheel-rail wear have great influence on vehicle’s running behavior. The design of those parameters of conventional railway does not give sufficient thought to the complicated wheel/rail dynamic interaction and the effect of the wheel-rail wear. It is of great theoretical value and engineering significance to analyze the influence factors of the railway wheel-rail wear from the perspective of dynamics and to adopt corresponding measures to reduce the wheel-rail wear.The simulation analysis method used in this paper is based on the theory of coupled vehicle/track dynamics. Dynamic analysis model for heavy haul railway vehicle curving is built by using the commercial software SIMPACK, and the nonlinear aspects of the vehicle system are taken into consideration. Elkins wear index as the wheel-rail wear index is used in the study of the wheel-rail wear problem on the small radius curve for heavy haul railway.Then the influence of the track alignment parameters (including the parameters of the curve radius, superelevation, rail cant, transition curve) on the wheel-rail dynamic interaction and wear is analyzed. Results show that vehicle curving performance is seriously influenced by worn rail profiles at different stages; curve radius is the decisive factor influencing on wheel-rail wear; it is beneficial for the reasonable superelevation to reduce the outer wheel-rail wear of the leading wheelset; Increasing the cant of the inner rail effectively improves the wheel-rail contact status and the curve negotiation of the vehicle. The improvement of the transition curve design can decrease the interaction forces of wheel and rail at the connection of the circle and the transition curve.Finally, the influence of the state of the wheel-rail contact surface on the wheel-rail wear is studied, which considers the reasonable matching friction coefficient of the inside and outside rails by changing the friction coefficient of inside and outside rails in the calculation model. Results show that changing of the friction coefficient has an important effect on the wear of both the wheel and rail; the wear on outer rail depends on the friction coefficient of the outer rail, and is effected by the friction coefficient difference between the inner and outer rails; the wear on the inter rail depends on the inter rail friction coefficient which is small, and the outer rail friction coefficient that is moderate. The wheel-rail wear can be reduced effectively under the condition of the reasonable matching of the friction coefficients of two rails.