【作者】 周亮节；

【导师】 刘建新；

【作者基本信息】 西南交通大学 ， 车辆工程， 2010， 硕士

【摘要】 铁路系统是以轮轨接触为基础的运输系统,钢轨在其中扮演了重要的角色。由于其上要支撑相当大的重量,无可避免的会出现各种损耗和破坏。而钢轨打磨是一种对钢轨进行维护的重要手段。通过对钢轨进行打磨,不仅能恢复钢轨的断面形状,还能有目的的改变其形状,达到预防钢轨伤损的发生与发展、改善轮轨接触性能的目的。因此,研究钢轨打磨形面就有很强的实际应用价值。本文在以下几个方面对钢轨打磨形面进行了研究：1.以车辆-轨道耦合动力学理论为基础,使用现场实测的钢轨形面数据,分析了曲线外侧钢轨磨耗后对车辆通过曲线的动力学行为的影响。分析表明钢轨磨耗后形面不能与车轮形面良好配合,会影响车辆的曲线通过性能,甚至可能引发安全事故。2.以减小轮轨接触界面法向间隙为目标,寻找了轮轨接触应力水平较小的钢轨打磨目标形面,为钢轨打磨方案的设计提供理论依据。根据三维非赫兹滚动接触理论寻找了轨头的优化范围,在此范围内能保证轮对动态横移过程中,轮轨接触点附近最小法向间隙的钢轨轨头外形。针对目前铁路线路接触应力大,磨损严重的问题,利用目前的方法对现有的60 kg/m钢轨进行了优化设计。利用车辆-轨道耦合动力学理论及三维弹性体非赫兹滚动接触理论对优化前后钢轨踏面与原车轮接触时静态接触性能及动态接触性能进行了分析。结果表明,优化后轮轨界面之间具有较好的“共形”接触特性,在不降低车轮其他动力学性能的情况下,钢轨形面优化后的轮轨接触应力显著地降低,可以有效降低轮轨磨耗。3.对高速线路钢轨缺陷的类型进行了介绍和分析,认为在钢轨缺陷形成的初始阶段对钢轨进行预防性打磨能有效防治缺陷的发展,延长钢轨使用寿命。随后,根据缺陷形成的位置、大小等特点,采用经验设计法设计出了一种适用于高速铁路钢轨预防性打磨的形面,并阐述了其构造过程。然后用SIMPACK软件及三维非赫兹滚动接触理论对其进行了动力学性能及接触力学性能的分析。结果表明,设计的钢轨预防性打磨形面与钢轨原始形面的各项性能均相差不大,符合预期。更多还原

【Abstract】 Railway system is a transport system based on wheel-rail contact. Rail played an important role in this system. Due to it must support considerable weight, it emergence of various destruction inevitably. Rail grinding is an important means of maintenance. Through rail grinding, not only to restore rail section shapes, but also with an aim to change its shape to the poupers of prevent the occurrence of rail failure and improvement the wheel-rail contact performance. Therefore, the study of rail grinding profile will have a strong practical value. This article do some study on rail grinding profile as followed:1. Based on the vehicle-track coupling dynamics theory, using field measurement data of rail profile, we analyse the vehicle’s curving performance while the outside rail is wear. The result shows the wear rail is not suit for the original wheel, it will affect the vehicle’s curving performance significantly, even it maybe evev lead to an anccident.2. With an aim to reduce the normal gap of wheel and rail, search a rail grinding profile of low contact stress level of wheels/rails, and support the theory foundation of rail grinding project. The optimization scope of the rail head is determined based on the theory of three-dimensional elastic bodies rolling contact with non-Hertzian. In the scope, the minimum gap forms between the original wheel and the improved rail when the wheelset shifts transversely. To mitigate the damage of the wheels and rails served in railways, this present method is utilized to optimize the profile of CHN60 rail. The theory of vehicle-track coupling dynamics and three-dimensional elastic bodies rolling contact with non-Hertzian are used to analyze the contact behavior of the wheel/rail before and after the rail profile optimization, in static and dynamic state. The results show that the optimized rail profile is in good conformal contact with LM wheel, which reduces wheel-rail contact stress significantly without sacrificing the dynamic performance, and the wear status of the left wheel-rail are decline. Therefore, the wear of the wheels and the rails can be decreased effectively by using the optimized rail.3. Analyse and introduce the type of rail defects in high-speed railway, consider that if grind the rail defects in the initial stages we can control the defects and extend the rail life. Then according to the location, size and other characteristics of defects, adopt empirical design method to design a rail profile of preventive rail grinding suit for high-speed railway, and describe the process of its construction. Subsequently use SIMPACK software package and CONTACT numerical procedure to analyse its dynamic performance and contact mechanical performance. The results show that the design of preventive rail grinding profile is little difference with the original profile, in line with expectation.更多还原