The University of Southampton
University of Southampton Institutional Repository

Discrete element simulation of railway ballast: modelling cell pressure effects in triaxial tests

Discrete element simulation of railway ballast: modelling cell pressure effects in triaxial tests
Discrete element simulation of railway ballast: modelling cell pressure effects in triaxial tests
The paper investigates reproducing the effects of confining pressure on the behaviour of scaled railway ballast in triaxial tests in discrete element models (DEM). Previous DEM work, using a standard Hertzian elastic contact law with an elastic–perfectly plastic tangential slip model, has been unable to replicate the behaviour observed in laboratory tests across a range of confining pressures without altering both the material stiffness and the inter-particle friction. A new contact law modelling damage at the contacts between particles is introduced. Particle contact is via spherically-capped conical asperities, which reduce in height if over-stressed. This introduces plasticity to the behaviour normal to the contact surface. In addition, the inter-particle friction angle is varied as a function of normalized contact normal force. At relatively low normal forces the friction angle must be increased for peak mobilized friction angles to match the laboratory data, an effect that is attributed to interlocking at the scale of surface roughness. Simulation results show close agreement with laboratory data.
1434-5021
1-13
Harkness, John
026f02e8-41d9-403f-83be-0d880058ecf1
Zervos, Antonios
9e60164e-af2c-4776-af7d-dfc9a454c46e
Le Pen, Louis
4a38e256-d113-4bba-b0d4-32d41995928a
Aingaran, Sinthuja
d1090eef-e035-43fb-8762-f0a600706911
Powrie, William
600c3f02-00f8-4486-ae4b-b4fc8ec77c3c
Harkness, John
026f02e8-41d9-403f-83be-0d880058ecf1
Zervos, Antonios
9e60164e-af2c-4776-af7d-dfc9a454c46e
Le Pen, Louis
4a38e256-d113-4bba-b0d4-32d41995928a
Aingaran, Sinthuja
d1090eef-e035-43fb-8762-f0a600706911
Powrie, William
600c3f02-00f8-4486-ae4b-b4fc8ec77c3c

Harkness, John, Zervos, Antonios, Le Pen, Louis, Aingaran, Sinthuja and Powrie, William (2016) Discrete element simulation of railway ballast: modelling cell pressure effects in triaxial tests. Granular Matter, 18 (3), 1-13, [65]. (doi:10.1007/s10035-016-0660-y).

Record type: Article

Abstract

The paper investigates reproducing the effects of confining pressure on the behaviour of scaled railway ballast in triaxial tests in discrete element models (DEM). Previous DEM work, using a standard Hertzian elastic contact law with an elastic–perfectly plastic tangential slip model, has been unable to replicate the behaviour observed in laboratory tests across a range of confining pressures without altering both the material stiffness and the inter-particle friction. A new contact law modelling damage at the contacts between particles is introduced. Particle contact is via spherically-capped conical asperities, which reduce in height if over-stressed. This introduces plasticity to the behaviour normal to the contact surface. In addition, the inter-particle friction angle is varied as a function of normalized contact normal force. At relatively low normal forces the friction angle must be increased for peak mobilized friction angles to match the laboratory data, an effect that is attributed to interlocking at the scale of surface roughness. Simulation results show close agreement with laboratory data.

Text
article10.1007s10035-016-0660-y.pdf - Version of Record
Available under License Creative Commons Attribution.
Download (4MB)

More information

Accepted/In Press date: 5 May 2016
e-pub ahead of print date: 7 July 2016
Published date: 1 August 2016
Organisations: Infrastructure Group

Identifiers

Local EPrints ID: 397977
URI: http://eprints.soton.ac.uk/id/eprint/397977
ISSN: 1434-5021
PURE UUID: 51258379-cd0c-4217-ba40-468e8eba96ec
ORCID for John Harkness: ORCID iD orcid.org/0000-0003-0908-0791
ORCID for Antonios Zervos: ORCID iD orcid.org/0000-0002-2662-9320
ORCID for Louis Le Pen: ORCID iD orcid.org/0000-0002-4362-3895
ORCID for William Powrie: ORCID iD orcid.org/0000-0002-2271-0826

Catalogue record

Date deposited: 13 Jul 2016 09:26
Last modified: 15 Mar 2024 03:24

Export record

Altmetrics

Contributors

Author: John Harkness ORCID iD
Author: Antonios Zervos ORCID iD
Author: Louis Le Pen ORCID iD
Author: Sinthuja Aingaran
Author: William Powrie ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×