Railroad Ballast Sizing and Grading

Abstract

The specified top size and grading of railroad ballast affects any economic evaluation and its performance in track. Both parameters affect any economic evaluation of ballast; as such it is essential to optimize both. The main source for ballast gradings in North America is the American Railway Engineering Association.s (AREA) Manual for Railway Engineering. Railroad ballast gradings tend, not only in North America but also world wide, to be uniformly graded. Herein a laboratory examination of ballast top size and grading are made in the triaxal apparatus. Particular attention will be paid to plastic strains, which cause rail twist, and strength, which affects lateral track stability.