Effects of Parallel Gradation on Strength Properties of Ballast Materials
The railroad ballast is used to fill in irregular surface topology, distribute and transfer loads from a surface structure or system to the subgrade or subsoils as uniformly and widely as possible in order to provide stable and stiff long-term embankment support for railways. A typical ballast grain sizes range from 30 to 70 mm, which makes large-scale laboratory tests difficult to conduct. The parallel gradation technique is to preserve the particle shape, particle surface roughness, and particle mineralogy, and creates a parallel gradation of soil with a maximum particle size for the available apparatus. This paper presents the result of a series of monotonic direct shear tests for three ballast materials having parallel gradation curves, which are served as background study for the ongoing research on validating it under loading-unloading condition.
D. Cambio and Y. L. Ge, "Effects of Parallel Gradation on Strength Properties of Ballast Materials," Geo-Denver 2007: New Peaks in Geotechnics, American Society of Civil Engineers (ASCE), Jan 2007.
The definitive version is available at http://dx.doi.org/10.1061/40917(236)14
Civil, Architectural and Environmental Engineering
Keywords and Phrases
Ballast; Material Properties; Embankments; Railroad tracks
Article - Conference proceedings
© 2007 American Society of Civil Engineers (ASCE), All rights reserved.