【作者】 张军；

【导师】 刘迎曦； 吴昌华；

【作者基本信息】 大连理工大学 ， 工程力学， 2003， 博士

【摘要】 当前世界铁路正朝着高速和重载的方向发展，随之而来的是列车牵引对轮轨粘着的要求越来越高，而轮轨的波浪形磨耗、滚动接触疲劳、脱轨等轮轨关系问题越来越严重，其解决与否直接影响到铁路的快速发展。这些问题的研究虽然涉及到许多学科，但都必须以轮轨滚动接触理论研究为基础，轮轨接触力的传递过程则是其核心内容。 轮轨关系是机车车辆、轨道系统中最基本、最复杂的一个问题，属于三维滚动摩擦接触问题。以Kalker为代表的国内外专家学者为轮轨滚动接触理论的发展做出了巨大的贡献，但他们的理论至今未突破Hertz接触条件和弹性半空间假设，无法对复杂的轮轨作用问题作进一步的研究。 大量的工程应用已充分证明有限元参数二次规划法是解决空间接触问题的一种先进的、行之有效的方法。本文采用基于参变量变分原理的有限元参数二次规划法，并结合多重子结构技术分析求解轮轨三维弹性和弹塑性接触问题，按照轮轨实际几何关系建立了真正的三维模型，完全避免了传统的解析或半解析法中的Hertz假设和弹性半空间假设。 本文建立了锥形踏面、磨耗形踏面的机车和车辆车轮分别与标准轨道相接触的三维有限元计算模型，模型还考虑了轨枕和部分道床的弹性作用。在大量弹性接触计算的基础上，又进行了大量弹塑性接触计算，得到了大量的轮轨接触力、接触状态及轮轨应力的数据。通过对计算结果的详细分析，得出了一系列机车车辆结构和运用参数对轮轨接触性能影响的规律。 本文建立了车轮轮缘贴靠钢轨形成的轮轨两点接触(对锥形踏面)和共形接触(对磨耗形踏面)的计算模型，对不同的牵引力矩、不同的横向力作用下的轮轨接触力、接触状态和轮轨应力分布进行了详细的分析，得出了轮轨间横向力增大会降低机车粘着性能等一系列重要结论。 本文提出了使用轮轨滚动接触时的轮周位移及接触斑长度计算蠕滑率的新方法，并绘制了在各种工况参数下的轮轨纵向蠕滑力／率曲线。分析了轮轨间的大连理工大学博士学位论文摩擦系数、轴重、横向力、轮轨几何型面、轮轨相对位置、塑性变形等诸多因素对轮轨纵向蠕滑率的影响。 本文的工作是用有限元法对轮轨三维弹性、弹塑性接触问题研究的全面应用，研究结果表明，将有限元法应用到轮轨关系方面的研究不但是可行的，而且还具有其它传统方法无可比拟的优越性，必然具有非常广阔的发展前景。更多还原

【Abstract】 The development tendency of the railway construction in the world today is serving high speed trains and csirrying heavy load. With the development arise some problems of the wheel/rail performance, the requirement of the train traction for the adhesion of wheel/rail will become more and more strict, and rail corrugation of wheel/rail, rolling contact fatigue and derailment will become more and more serious. The solution to the problems will have direct effects on the railway development. Although the investigations in the problem are concerned with many disciplines, they are all based on the theory of wheel/rail rolling contact, in which the transmission process of wheel-rail contact force is the core.The performance of wheel/rail is the most elementary and most complicated problem of locomotive and vehicle and rail system. It is a 3D rolling frictional contact problem. Some experts and scholars with Kalker as a representative have contributed a lot to the development of wheel/rail rolling contact theory. But their theory hasn’t broken the limit of Hertz contact conditions and elastic-half-space assumption, which cannot be used to make further investigation in the problem of, complicated wheel/rail reaction.Lots of engineering applications demonstrate that the finite element parametric quadratic programming method (FEPQPM) is an advanced and efficient method in solving 3D contact problems. In this paper, the wheel/rail 3D elastic and elastoplastic contact problem is analyzed and solved by using FEPQPM, which is based on the parametric variational principle. And the multi-substructure technique is also used. The model is built according to the actual geometric relation. The Hertz assumption and the elastic-half-space assumption in the classical analytical or half-analytical method are completely avoided.In this paper, the 3D FEM models of cone-tread and worn-tread locomotive and vehicle wheels are firstly established, which come into contact with the rail of standard size. There hasn’t been any more refined 3D FEM computation model of wheel/rail up till now. The elastic effect of crosstie and roadbed is also considered. Lots of the elastic contact problems and elastoplastic contact problems are computed. A lot of data such as the wheel/rail contact force; contact status and wheel/rail stress distribution are obtained. After detailed analysis of the computation results, some lawsIIIare obtained on how the structures of locomotive and vehicle and some applied parameters affect the performance of wheel/rail contact.The computation model of two-point contact (for cone-tread) and conformal contact (for worn-tread) resulting from wheel flange close to rail is firstly established in this paper. A detailed analysis is made of the wheel/rail contact force, contact status and wheel/rail stress distribution on the different action of tractive forces and transverse forces. We draw some important conclusions, one of which is that the locomotive adhesion performance will decrease with the increase of transverse forces between wheel and rail.The method of computing creep using displacement of wheel periphery and the length of contact surface is applied. The curves of wheel-rail longitudinal creep forces and creepages are drawn for different load case factors. The effect on wheel-rail longitudinal creep forces and creepages of friction coefficients, axle loads, transverse forces, wheel/rail geometry surface, the relative position of wheel/rail and plastic deformation is also studied.The research here is a fundamental and complete application of FEM to wheel/rail 3D elastic contact and elastoplastic contact problems. The results show that this research work is not only feasible, but it also has some advantages over the classical methods. It will have a greater development prospect.更多还原