TY - GEN
T1 - Discrete Element modeling and analysis of shielding effects during the crushing of a grain
AU - Wang, P.
AU - Bakhtiary, E.
AU - Ecker, S.
AU - Arson, C.
AU - Christopher, T.
AU - Francis, K.
N1 - Publisher Copyright:
Copyright 2015 ARMA, American Rock Mechanics Association.
PY - 2015
Y1 - 2015
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=84964994078&partnerID=8YFLogxK
M3 - Conference article published in proceeding or book
AN - SCOPUS:84964994078
T3 - 49th US Rock Mechanics / Geomechanics Symposium 2015
SP - 1622
EP - 1627
BT - 49th US Rock Mechanics / Geomechanics Symposium 2015
PB - American Rock Mechanics Association (ARMA)
T2 - 49th US Rock Mechanics / Geomechanics Symposium
Y2 - 29 June 2015 through 1 July 2015
ER -