扣件支承模拟方式对车辆-轨道动力学行为的影响

针对车辆-轨道耦合动力学模型中扣件支承的模拟方式,建立了车辆-轨道动力学精细化空间实体模型,研究了扣件支承方式分别为单点支承、多点支承以及连续支承时,轮轨相互作用力、钢轨振动加速度、钢轨受力变形等动力学行为的差异。结果表明:(1)轮轨相互作用方面,扣件模拟为单点支承时轮轨垂横向力最大,连续支承时轮轨垂横向力最小,多点支承时轮轨垂横向力介于两者之间。(2)单点支承模型的钢轨和轨道板振动加速度明显大于多点支承和连续支承。(3)钢轨在单点支承条件下,由于轨底局部支承应力较大,钢轨的动弯应力和动位移均大于多点支承和连续支承情况。因此,在建立精细化的车辆-轨道动力学模型时采用多点支承形式来模拟扣件系统是较为合理的。

Influence of Simulation Mode of Fastener Supporting on Vehicle-track Dynamic Behavior

The vehicle-track dynamic model is established based the simulation mode of fastener supporting. The differentiations in dynamic behavior in terms of wheel-rail force, rail vibration acceleration and rail deformation in various fastener supporting modes including single-point supporting mode,multi-point supporting mode and continuous supporting mode are studied. Results show that:( 1)for wheel-rail interaction relationship,the vertical and lateral wheel-rail force is the largest for singlepoint supporting mode and smallest for continuous supporting mode,the value of vertical and lateral wheel-rail force of multi-point supporting mode rests between single-point mode and continuous mode;( 2) the value of vibration acceleration of rail and slab for single-point supporting is obviously larger than that of the other two supporting modes;( 3) the moment and displacement of single-point supporting mode is the largest of the three supporting modes due to the large local bearing force in rail foot. Thus,the establishment of vehicle-track dynamic model with multi-point supporting mode is appropriate to simulate fastener system.