短波随机不平顺对列车-板式无砟轨道-路基系统振动特性的影响

摘要

A rail- slab track-subgrade vertical vibration model was put forward based on finite element method, vibration equations were formulated by using the principle of total potential energy with stationary value in elastic system dynamics and the "set-in-right-position" rule for formulating matrixes.Using high-speed train passing slab track on subgrade as example, influence of short-wave random irregularity on vertical vibration responses of train-slab track-subgrade system was studied, and vertical vibration responses of train-slab track -subgrade system were compared with short-wave random irregularity and other kinds of random irregularity.The calculated results show that short-wave random irregularity has little effect on vertical acceleration of vehicle and vertical pressure stress on subgrade; it has some effect on vertical pressure force of fastening, bending stress of slab and bending stress of concrete basement; and it has siguificant influence on vertical acceleration of rail, vertical acceleration of slab, vertical acceleration of concrete basement, vertical pressure force on CA mortar, and the influences of short wave random irregularity even surpasses the influence of middle-long wave random irregularity.Short-wave random irregularity can be neglected to study the dynamics characteristic of vehicle and subgrade, but it should be considered to study the dynamic characteristic of components of slab track.%运用弹性系统动力学总势能不变原理及形成矩阵的"对号入座"法则,建立列车-板式无砟轨道-路基竖向振动方程组,分析列车高速运行时,短波随机不平顺对列车-板式无砟轨道-路系统振动特性的影响,并对不同种类随机不平顺对列车-板式无砟轨道-路基系统动力特性的影响进行对比研究.研究结果表明:短波随机不平顺对车体垂向加速度、路基竖向压应力影响很小,对扣件竖向压应力、轨道板及底座板弯曲应力有一定的影响,对轮轨垂向力、钢轨振动加速度、轨道板振动加速度、底座板振动加速度和CA砂浆压应力则有显著的影响,影响超过中长波随机不平顺.研究车体及路基动力特性时可以不考虑短波随机不平顺,研究无砟轨道各部件动力特性时,则应考虑短波随机不平顺.