"Due to the difficulties involved with testing large particle granular materials such as rockfill and railroad ballast, several methods of testing scaled down model specimens have been introduced. Of these techniques, the parallel gradation model has been found to be most useful. The parallel gradation model states that a smaller grainsize distribution model granular material, of the same composition as the prototype material, can be used in triaxial testing at a scaled down grainsize, if the model materials grainsize is exactly parallel to the prototype material. Therefore, a model granular material composed of a smaller, but parallel, grainsize distribution can be used to predict shear and compressive properties of a larger rock fill material. Because railroad ballast is loaded in a cyclical fashion, cyclical triaxial testing is considered a reliable method of analysis of strength and deformation characteristics. The objective of this study is to assess the suitability of the parallel gradation modeling technique for physically modeling permanent axial and volumetric strains, and resilient modulus of scaled down granular materials"--Abstract, iii.
Ge, Yu-Ning (Louis)
Rogers, J. David
Stephenson, Richard Wesley
Maerz, Norbert H.
Richardson, David Newton
Civil, Architectural and Environmental Engineering
Ph. D. in Civil Engineering
Missouri University of Science and Technology
xi, 125 pages
© 2008 Adam F. Sevi, All rights reserved.
Dissertation - Open Access
Library of Congress Subject Headings
Ballast (Railroads) -- Testing
Railroad tracks -- Foundations
Shear strength of soils -- Testing
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Sevi, Adam F., "Physical modeling of railroad ballast using the parallel gradation scaling technique within the cyclical triaxial framework" (2008). Doctoral Dissertations. 1929.