Analysis On Influence Of Heavy-haul Railway Line Curve Parameters On Rail Wear

The axle load of heavy-haul railway trains increases and the rail wear of curve is more obvious with the development of heavy-load railway. Therefore,it becomes one of the most urgent problems to control rail wear effectively for heavy-haul transport. Line curve parameters is one of the most important factors that affect rail wear,so this article mainly studies the influence and rational design of the parameters to reduce the rail wear and improve the service life of rails.Firstly,establishes a rail-wear simulation system with kinetic theory,non-elliptical contact theory, FASTSIM algorithm and Archard model for trains with 30t axle load. The rationality of rail-wear simulation system is tested by the measured rail-wear data of Shuohuang heavy-haul railway.Secondly, in circular curve segment, the influence of the parameters such as radius of the curve, length of transition curve, superelevation, rail cant and track irregularity are analyzed according to the rail-wear simulation system based on the evaluation indexes including maximum wear depth, vertical wear and side wear. Results show that: The wear of the outer rail is mainly concentrated on the inside and the shoulder and the wear of the inner rail is mainly concentrated in the middle of railhead. Curve radius has a greater impact on rail wear and the rail wear abruptly decrease with the increase of curve radius. As the radius of curve increases, the amplitude of reduction and reduction rate of the rail wear decreases; Wear of rail decreases as the length of transition curve increases; The rail wear is less when the curve track is set with deficient superelevation than with surplus superelevation from the aspect of reducing rail wear; Under the conditdion than LM tread is used to match the CN75 rail, rail wear is minimum when rail cant is 1/40; Wear of outer rail decreases as wheel-rail friction coefficient decreases, the friction coefficient is recommended to be less than 0.25; Good railway line condition is helpful to decrease rail wear.Finally, in transition curve segment, the influence of the parameters such as length of transition curve, rate of superelevation, rail cant wheel-rail friction coefficient and track irregularity are further analyzed according to the rail-wear simulation system. Results show that: The wear of the outer rail is mainly concentrated on the shoulder and the wear of the inner rail is mainly concentrated in the middle of railhead. Wear of rail decreases as the length of transition curve increases and is less affected by the length of transition curve than that in circular curve segment; Wear of outer rail increases as rate of superelevation increases; Outer rail cant is supposed to be 1/20 and inner rail cant is supposed to be 1/30 under the conditdion than LM tread is used to match the CN75 rail; Wear of outer rail decreases as wheel-rail friction coefficient decreases, the friction coefficient is recommended to be less than 0.15; Good railway line condition is helpful to decrease rail wear.