运动车轮重力正向碰撞作用下钢轨界面应力特征

Interface stress characteristics of normal collision on rail under a wheel with gravity and initial velocity

在重力及初速度作用下,车轮与钢轨的接触过程,可用碰撞作用描述。碰撞全过程中,车轮在初速度、重力以及接触界面反力共同作用下经历先加速后减速2个运动阶段。基于碰撞理论与应力波理论,以重力作用下、具有正向初速度的无限长圆柱体(刚体)侧面与弹性半空间正向碰撞这一过程为研究对象,按照应力波理论确定碰撞界面应力强度,根据牛顿第一、第二定律,建立圆柱体运动方程,运用微分几何原理,解析运动状态参数的函数关系,并由此推导界面及界面质点元应力脉冲形成过程及其时-域规律,为重力与正向初速度作用下轮轨正向碰撞界面应力研究提供参考。

The contact process between wheel and rail under gravity with initial velocity can be described as collision effect.The wheel accelerates firstly and then decelerates under the effect of gravity and interface reaction during the whole collision process.In this paper,the normal collision between the lateral surface of an infinite cylinder with initial velocity under gravity and an elastic half space was taken as the research object,stress intensity at the collision interface was determined by stress wave theory and the motion equation of the rigid body(infinite cylinder)was established according to Newton first and second laws.The function relationships of motion state parameters were solved through differential geometry principle,by which the laws of time-domain were deduced.The research results provide research basis for the excitation process study of interface stress wave generated by normal collision between wheel and rail acted by gravity and initial velocity.