无砟轨道路基动力响应影响因素分析

以双块式无砟轨道路基典型结构为研究对象，分析车辆轴重、结构层间接触条件、轨道结构整体模量、支承层模量和基床表层模量等对路基面动力响应的影响，分析路基动力响应对各参数的敏感性。数值仿真结果表明:在车辆单轴荷载作用下，路基面动应力分布表现为横向均匀、纵向三角形的基本形式；对路基面动应力沿线路纵向分布长度影响的主要因素，是无砟轨道结构的整体刚度、车辆轴重、支承层模量等；结构面间接触状态劣化导致无砟轨道结构刚度的降低和路基面的动压力增大。

Analysis on Factors Affecting Dynamic Response of Ballastless Track Subgrade

Taking the typical structure of double-block ballastless track subgrade factors affecting dynamic response of subgrade surface, such as axle weight of as the object of study, the vehicle, interlayer contact condition, modulus of whole track structure, bearing layer and surface layer of subgrade are analyzed, and so is the sensitivity of the dynamic response of the subgrade to these parameters. The results of numerical simulation show that dynamic stress distribution on the subgrade surface under vehicle uniaxial load performs laterally uniform and longitudinally triangle; the main factors affecting the longitudinal distribution of such dynamic stress along the road include integral rigidity of the ballastless track structure, vehicle＇s axle load and bearing layer modulus; and the deterioration of interlayer contact condition leads to stiffness decrease of the ballastless track structure and dynamic pressure increase of the subgrade surface.