The Research on the DEM Simulation of the Railway Ballast Tamping Process

Abstract

Ballast degradation and unrecoverable deformation are emerged on the railway ballast track under the loads of high-speed and heavy loading locomotive. With the change of tamping frequency, a better understanding of the physics of compactness degree is important for long-time stability of ballast. This paper presented a numerical investigation of the bulk materials dynamics and the transient impaction of a system of irregular polyhedral particles confined with a rectangular box with a retaining wall subjected to cyclic tamping loading. Sphere packing method was being used in this study to simulate typical full-sized ballast particles. This paper aimed to establish firm-soft coupling particle-flow tamping operation simulation numerical model based on contact dynamics theory. This study checked the validity of the model while different tamping working conditions and out-loads was being implemented. The study shows that discrete element method (DEM) is an efficient method to reveal the rearrangement rule of railway ballast after the process of tamping operation.