【作者】 肖新标；

【导师】 沈火明；

【作者基本信息】 西南交通大学 ， 一般力学与力学基础， 2005， 硕士

【摘要】 列车脱轨是危及铁路行车安全的主要因素,轮轨型铁路运输系统最基本的安全要求就是保证不发生列车脱轨事故。长期以来,世界各国铁路部门和科研人员开展了大量的脱轨理论与试验研究,取得了丰硕成果。但由于脱轨问题的复杂性和研究的困难性,至今,脱轨事故仍时有发生,特别是在中国,脱轨事故占铁路行车重大、大事故70%左右,严重影响着中国铁路运输的经济效益和社会效益。已有的脱轨研究,都没有较好地考虑轨道运动对轮轨接触几何、蠕滑率/力和脱轨的影响。本文的主要工作有: (1) 基于弹性轨道模型,根据轮轨空间接触几何关系,将车轮踏面及钢轨踏面通过曲面拟合成三次样条函数,对最小距离搜索法进行改进,实现一种考虑轨道横移、垂向平移和翻转运动的改进轮轨接触几何算法。分析了轨道横移、垂向平移和翻转运动对锥形踏面轮对和磨耗型踏面轮对轮轨接触几何的影响。 (2) 推导了能考虑轮对及轨道运动的轮轨接触蠕滑率。在轮轨滚动接触蠕滑率/力关系分析方面,首先按Kalker线性理论计算,然后采用Shen-Hedrick-Elkins理论进行非线性修正。分析了轮对横移、摇头及轨道横移、垂向平移和翻转运动对轮轨滚动接触蠕滑率/力的影响。 (3) 简评了现有脱轨准则,采用经典和近似解析的方法推导了单轮对稳态脱轨准则。基于这个准则,分析了基本脱轨参数和轮对及轨道运动对脱轨的影响。 研究结果表明,轨道运动对轮轨接触几何及轮轨滚动接触蠕滑率/力的影响较大,而对临界脱轨的影响较小。更多还原

【Abstract】 The basic requirement for the safety of railway transportation system is that derailment during the running of train should never be permitted. The mechanism of derailment has been investigated by almost all railway administrations and scientists for many years. Much progress has been made with theoretical and experimental methods. However, due to the complexity of derailment and the difficulty of research, derailment accidents still often happen. Especially in china, derailment accident accounts for about 70 percent of traffic accidents on railway transportation, which has a significant influence on the economy and society benefit of railway transportation of China. In the past studies, the effect of the motions of wheelset and rail on the contact geometry, creepage, creep force and derailment in wheel/rail rolling contact is not yet taken into consideration. The current study is summarized as follows:(1) Based on the elastic rail model and the relationship of wheel/rail spatially contact geometry, the traditional least-distance-search algorithm is improved by fitting the treads of wheelset and rail into a cubic interpolation function. A amendatory algorithm for wheel/rail spatially contact geometry is proposed, which can take the rail roll-over, rail lateral displacement and rail vertical displacement into account. According to the developed algorithm, the effect of rail roll-over, rail lateral displacement and rail vertical displacement on wheel with cone-tread and worn-tread and rail contact geometry is analyzed.(2) A wheel/rail rolling contact creepage which can consider the effect of rail roll-over, rail lateral displacement and rail vertical displacement is obtained. Kalker’s linear theory and Shen-Hedrick-Elkins non-linear theory are employed to determine creep forces. The influence of rail roll-over, rail lateral displacement and rail vertical displacement on creep force and creepage of wheel/rail is analyzed.更多还原