Strength and Deformation Characteristics of Railroad Ballast in Ballast Particle Abrasion Process

Abstract

This study describes the shape evaluation method to determine the abraded state of ballast particles in order to evaluate ballast performance in terms of strength and deformation under cyclic train loads. The authors explain the conditions of ballast under live train operations that make this type of evaluation necessary, particularly the degree to which waste ballast can be recycled and differential settlement occurs. The shape evaluations were accompanied by large triaxial and cyclic loading tests with a large-scale track model to determine the degree of abrasion, the shapes that ballast particles assume during and after abrasion, and their performance characteristics. Sample shapes are provided, along with descriptions of test results and figures illustrating track models used. Three sets of conclusions are presented as substantiating the finding that shape evaluation is an acceptable method for ballast abrasion estimates.