铁路直线轨道空间振动时变模型研究

Study on a Time-varying Spatial Model of Railway Tangent Track Vibration

采用有限单元法,将轨枕视为线性粘弹性连续支承梁单元,钢轨划分为线性粘弹性点支承梁单元,分别考虑每个单元的横向、纵向、竖向及扭转振动,建立铁路直线轨道结构空间振动模型。运用弹性系统总势能不变值原理,采用轨道不断"增加和缩减"技术,建立直线轨道结构空间振动时变质量、阻尼和刚度矩阵。以国产25Z型客车为例,计算200s时间段上车辆—轨道耦合振动动力响应,与实测结果比较吻合。

By using finite element method, the sleeper was divided by linear viscoelastic continuously supported beam element and the rail was divided by linear viscoelastic discretely supported beam element. The lateral vibration, longitudinal vibration, vertical vibration, bending vibration and torsional vibration of each element node were considered. A time-varying model of railway tangent track spatial vibration was proposed. The time-varying mass matrix, damp matrix and stiffness matrix of track spatial vibration were set up by using the principle of stationary total potential energy in elastic system dynamics, and the technology of track added and cut down. Taking a Chinese 25Z vehicle as an example, the dynamic response of the vehicle-track coupling vibration in 200 s are calculated, which is very close to the spot testing results.