Discrete Element modeling and analysis of shielding effects during the crushing of a grain

P. Wang, E. Bakhtiary, S. Ecker, C. Arson, T. Christopher, K. Francis

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review

2 Citations (Scopus)

Abstract

The potential for a particle to crush under one-dimensional compression is critically dependent on the coordination number of that particle. Neighboring particles decrease deviatoric forces at contacts, which reduces tensile stress and subsequent fracture propagation in the crushable particle. This phenomenon is called "shielding effect". In this paper, we model a sand particle as a spherical cluster of bonded, hexagonally packed, equally sized, non-breakable spheres with the Discrete Element Method (DEM). We use rigid walls to apply forces at the contact with neighboring particles. First, we calibrate the cluster mechanical parameters against published experimental results obtained during unconfined uniaxial compression tests. Then we propose a procedure employed in DEM to generate symmetric and random distributions of walls. We use two loading walls only: the remainder of the walls is used for passive shielding. Force-displacement curves obtained during the crushing simulations clearly show that the peak force reached when the cluster first splits increases with the number of shielding walls, which demonstrates shielding effects. The total resulting compression force applied by the walls increases linearly the coordination number. We expect that our computational method will allow the optimization of crushing in powder technology, and the prevention of crushing in geotechnical engineering.

Original languageEnglish
Title of host publication49th US Rock Mechanics / Geomechanics Symposium 2015
PublisherAmerican Rock Mechanics Association (ARMA)
Pages1622-1627
Number of pages6
ISBN (Electronic)9781510810518
Publication statusPublished - 2015
Externally publishedYes
Event49th US Rock Mechanics / Geomechanics Symposium - San Francisco, United States
Duration: 29 Jun 20151 Jul 2015

Publication series

Name49th US Rock Mechanics / Geomechanics Symposium 2015
Volume3

Conference

Conference49th US Rock Mechanics / Geomechanics Symposium
Country/TerritoryUnited States
CitySan Francisco
Period29/06/151/07/15

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology

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