Analysis of influence of ballast shape on abrasion resistance using discrete element method. (1st March 2021)

• Record Type: Journal Article
• Authors: Xu, Yang; Yu, Wenying; Qie, Luchao; Wang, Hong; Ning, Na
• Is Part Of: Construction & building materials. Volume 273(2021)
• Publication Date: 2021-03-01
• Subjects: Discrete element method -- 3D reconstruction -- Grain shape -- Los Angeles abrasion test -- Railway ballast; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.121708
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Photogrammetry-based 3D Reconstruction Method for ballast shape simulation. Crushable DEM models of ballasts based on the cell-derived method. Numerical model was validated by Los Angeles abrasion test. Influence analysis of ballast shape on abrasion resistance. Abstract: The ballast resistance performance—an important indicator of the performance and maintenance of railway ballast—is strongly dependent on the ballast shape, but this relationship is not yet fully understood. Despite many attempts to model the constitutive behavior of the ballast under cyclic loading using the discrete element method (DEM), few studies have obtained any conclusive results on the ballast breakage behavior. Therefore, in this study, a series of innovative techniques have been adopted to develop a crushable-ballast DEM model, and this model is further calibrated using the results of the Los Angeles abrasion (LAA) test. The results indicate both needle-shaped and flake-shaped ballast samples tend to break more easily than the normal-shaped samples. Thus, only the normal-shaped ballast samples are recommended for LAA test. Furthermore, by considering the ballast dynamic stability, a strict restriction on the proportion of needle-shaped ballast (≤10%) was recommended as the relevant technical standard.