基于快速拉格朗日的板式无砟轨道路基动力响应研究

Study on Dynamic Response of Slab Ballastless Track Subgrade Based on Fast Lagrangian Analysis of Continua

将列车荷载简化为一激振力并作为等效轮轴荷载,运用FLAC3D内置的FISH语言编程实现列车荷载的定时、定点施加,从而模拟列车在轨道结构上的移动加载过程。以遂渝线板式无砟轨道路基结构为对象,建立三维动力分析模型,基于FLAC3D计算平台,利用编制的动力加载程序对轨道路基结构进行了动力响应计算,分析了列车移动荷载作用下路基各结构层的动位移、动应力响应特性以及动响应在路基深度范围内的衰减特性,并以基床表层为研究对象,着重考察了其刚度变化对路基动力响应的具体影响。

The railway traffic loads are simplified as an exciting force and acted as equivalent axle load. The vibration loads in ground induced by the moving marshalling train were simulated by using multi-support excitation which was developed by programming FISH language in FLAC3D. A theoretical model of track-subgrade system based on slab ballastless track in Suining—Chongqing Railway Line was presented by employing a 3-dimensional dynamic analysis method, and based on FLAC3D computing platform, the dynamic response of track subgrade structure is calculated by using the dynamic loading program. The dynamic response characteristics of displacement and stress in each structure layer of subgrade and attenuation in subgrade depth are analyzed. In addition, the specific influence of stiffness variation of the surface layer of subgrade on dynamic response is investigated.