浮置板断簧条件下的列车-轨道耦合系统动力特性分析

Dynamic Characteristics Analysis of the Train-Track Coupled System with Broken Springs of Floating Slab

针对昆明地铁4号线工程设计实践,基于车辆-轨道耦合动力学理论,建立列车-钢弹簧浮置板轨道垂向耦合动力学模型。分析了钢弹簧容易发生断裂的位置,研究了钢弹簧的断裂位置和断裂数量对列车-轨道耦合系统垂向振动的影响。结果表明:浮置板中部附近的钢弹簧更容易发生断裂;断簧数量越多,车体垂向加速度、钢轨和浮置板的垂向位移及其垂向加速度、钢弹簧支点力越大,且沿轨道纵向恢复越慢;在断簧数量相同的情况下,板端断簧时的车体、钢轨、浮置板的垂向加速度比板中断簧时的大,板端断簧时的钢弹簧支点力比板中断簧时的小;如果断簧数量大于2对,板中断簧时的钢轨、浮置板的垂向位移将超过板端断簧时的垂向位移;当断簧位置出现在板端时,板端扣件会受到压缩力和拉伸力的循环作用,不利于扣件的使用寿命。

According to the engineering design of Kunming Metro Line 4,a dynamic model for the train-track of steel spring floating slab vertical coupled system is established based on the theory of vehicle-track coupled dynamics to identify the position where steel springs are likely to break and study the effects of the position and number of broken steel springs on the vertical vibration of the train-track coupled system.The results show that the steel springs near the middle of the floating slab are more likely to break;the more the number of broken springs,the greater the vertical acceleration of car body,the vertical displacement and acceleration of rail and floating slab,the force of steel spring,and the slower the recovery of them in longitudinal direction;in the case of the same number of broken springs,the vertical acceleration of car body,rail and floating slab with broken springs located at the end of slab are larger than that with broken springs in the middle of slab,and the force of spring with broken springs at the end of slab is smaller than that with broken springs in the middle of slab;if the number of springs is greater than 2 pairs,the vertical displacement of rail and floating slab with broken springs in the middle of slab will be larger than that with broken springs at the end of slab;when the position of broken springs appears at the end of slab,the fastener at the end of slab will be subjected to the cyclic action of compressive force and tensile force,which is not conducive to the service life of the fastener.