The Theory And Test Research On Rail Asymmetric Grinding For The Passenger And Freight Railway

The intense wheel-rail interaction resulting from railway heavy haulage leads to a series of damages of the rail in the curve section such as side grinding, crushing, corner fine cracks and waving grinding. The costs of the maintenance and fault repairing for the rail are very high. The application experience at home and abroad manifests that profile optimization of the rail by asymmetrical grinding is one of the methods by which the growth rate of rail diseases in the curve section is restrained to extend the life span of the rail. However there is no relative analysis and experiment on it. This paper centers on the rail asymmetrical grinding technology to develop theoretical analysis and experiment research in view of several aspects as follows.1.Based on the wheel-rail contact theory, the calculation method about geometrical relationship and contact force of wheel-rail contact either in dynamic state or static state is deduced. And the wheel-rail contact model aimed at the analysis of rail profile optimization is established.2.To take the wheel-rail dynamic contact relationship into account, the dynamic model of dimensional wheel-rail system is established and relative oscillation equation is deduced. Besides the simulation calculation program is compiled to research the influence of the variation of rail profile in the curve section on driving safety and stability as well as rail wear and dynamic properties.3.The principle and method about rail profile optimization are put forward. This method supports choice making from various schemes to ascertain the optimum target rail profile.4.On the basis of high-speed photography and the principle of machine vision, the visualization detector related to wheel-rail contact is developed to test the wheel-rail contact condition in circuit.5.The experiment on the rail asymmetrical grinding in the curve section of mixed passenger and freight line is guided by the method of rail profile optimization. The experiment research on rail profile, wheel-rail contact condition and light band distribution state is conducted. The wheel-rail system dynamics is applied to dynamic simulation of passenger and freight train. The test results are basically corresponded with theoretical analysis.6.The grinding experiment and theoretical research indicate that the wheel-rail interaction of freight train can be effectively decreased by adopting asymmetrical grinding in the small radius inadequate superelevation section. Asymmetrical grinding and standard profile recovery grinding can be applied to the wearing rail. Asymmetrical grinding has a little effect on the stability of passenger train, but no obvious effect on the safety.