针对浮置板式轨道结构特点,取相邻2个扣件之间的轨道为1个轨段单元,钢轨视为连续弹性点支承Euler梁,浮置板视为弹性薄板,扣件系统及橡胶支座均模拟为线性弹簧及粘滞阻尼器,建立浮置板式轨道振动模型;将城轨列车中的车辆均离散为多刚体系统,各刚体之间通过线性弹簧及粘滞阻尼器相连,建立列车振动模型;将浮置板式轨道及列车振动势能叠加,得到系统竖向振动总势能:基于弹性系统动力学总势能不变值原理及形成系统矩阵的“对号入座”法则,建立此系统竖向振动矩阵方程;采用Wilson-θ逐步积分法求解此矩阵方程,得出此系统竖向振动响应。研究结果表明:采用浮置板式轨道振动模型计算的钢轨竖向位移为4.18mm。浮置板竖向位移为0.69mm,与已有研究结果吻合良好:城轨列车以速度60km/h在浮置板式轨道上运行时的系统竖向振动响应波形图符合物理概念,响应的量值反映了系统竖向振动的通常幅值。
According to structural characteristics of floating slab tracks, a track segment element was taken between two adjacent fasteners. For each element, rails were regarded as Euler beams supported by discrete viscoelastic supports. The fasteners and rubber supports were replaced by a linear spring and damp. So the vibration model of the floating slab track was established. In constructing vibration model of a metro train, each car of the metro train with two suspensions was modeled as a multi-rigid body system, in which rigid bodies were connected with each other by a linear spring and damp. Combining the potential energy of vertical vibration of the track with that of the metro train, the total potential energy of vertical vibration of the train and track was obtained. And then, the matrix equation of vertical vibration of the system was established using the principle of total potential energy with stationary value in elastic system dynamics and the "set-in-right-position" rule for formulating system matrices. The vibration responses of the system can be obtained by solving the matrix equation with the direct time integration such as Wilson-θ method, The results show that by using the floating slab track vibration model, the vertical rail displacement is 4.18 mm and the vertical floating slab displacement is 0,69 mm, which is consistent with the existing results. When the metro train runs on the floating slab track at 60 kin/h, the waveforms of vertical vibration of the system accord with the physic concepts and the vibration response values reflect the general vibration magnitudes of the system.