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Title: Particle Size Effects on the Strength and Fabric of Granular Media
The reliance on sand-based methods for the characterization and design of gravelly soils is necessitated in part by a limited understanding of how to account for the effects of particle size and distribution. In this paper, particle size effects on the strength and fabric of cohesionless, granular media are investigated using the discrete element method by testing specimens with particle size distributions (PSDs) of differing coefficient of uniformity (CU) and mean grain size (d50). Preliminary results show that when all particle shape characteristics are equal, increasing d50 yields equivalent stress-strain responses for the same relative density (DR) and CU. However, when increasing CU, specimens exhibit more dilative tendencies and greater shear strengths. Increasing CU results in more dispersive distributions of contact force, stress, and coordination number. The void ratios associated with minimum and maximum density, and constant volume conditions during shear also decrease with increasing CU.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
GeoCongress 2020
Page Range / eLocation ID:
349 to 358
Medium: X
Sponsoring Org:
National Science Foundation
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