ABSTRACT
Ballast degradation macroscopically leads to ballast contamination and worse track quality, thus causing higher operation and maintenance cost. Microscopically, it manifests as ballast particle form, corner and surface texture alteration. To reveal the mechanism of ballast degradation, the Los Angeles Abrasion (LAA) test is conducted, and the 3D laser scanner is utilized to get images before and after the test. During the test, the geometrical parameters of ballast particles are changing, including volume, form, corner and surface texture. After comparing the geometrical parameters, it demonstrates that the main abrasion loss results from corner attrition, the maximum abrasion depth is between 4–9 mm, and the average abrasion depth is within 1 mm. The abrasion loss increases with ballast particle size. The results are useful for ballast material standard, degradation evaluation and maintenance.
