Analysis of mesoscopic mechanical dynamic characteristics of ballast bed with under sleeper pads  

作　　者：Xiong Yang Liuyang Yu Xuejun Wang Zhigang Xu Yu Deng Houxu Li 

机构地区：[1]Faculty of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming,China [2]Yunnan Provincial Key Laboratory of Advanced Equipment Intelligent Manufacturing Technology,Kunming,China

出　　处：《Railway Engineering Science》2024年第1期107-123,共17页铁道工程科学（英文版）

基　　金：supported by the National Natural Science Foundation of China under Grants Nos.52165013 and 51565021.

摘　　要：The meso-dynamical behaviour of a high-speed rail ballast bed with under sleeper pads(USPs)was studied.The geometrically irregular refined discrete element model of the ballast particles was constructed using 3D scanning techniques,and the 3D dynamic model of the rail-sleeper-ballast bed was constructed using the coupled discrete element method-multiflexible-body dynamics(DEM-MFBD)approach.We analyse the meso-mechanical dynamics of the ballast bed with USPs under dynamic load on a train and verify the correctness of the model in laboratory tests.It is shown that the deformation of the USPs increases the contact area between the sleeper and the ballast particles,and subsequently the number of contacts between them.As the depth of the granular ballast bed increases,the contact area becomes larger,and the contact force between the ballast particles gradually decreases.Under the action of the elastic USPs,the contact forces between ballast particles are reduced and the overall vibration level of the ballast bed can be reduced.The settlement of the granular ballast bed occurs mainly at the shallow position of the sleeper bottom,and the installation of the elastic USPs can be effective in reducing the stress on the ballast particles and the settlement of the ballast bed.

关 键 词：Under sleeper pads Ballast bed Discrete element method Mesoscopic mechanical dynamic characteristics 

分 类 号：U213.7[交通运输工程—道路与铁道工程]