Implementation of real contact behaviour in the DEM modelling of triaxial tests on railway ballast

Tolomeo, Mathias; McDowell, Glenn R.

doi:10.1016/j.powtec.2022.118021

Authors

MATHIAS TOLOMEO MATHIAS.TOLOMEO@NOTTINGHAM.AC.UK
Research Fellow

GLENN MCDOWELL GLENN.MCDOWELL@NOTTINGHAM.AC.UK
Professor of Geomechanics

Abstract

In the Discrete Element modelling of soils, the micromechanical behaviour at contacts has often been considered to have a minor influence on the macromechanical response, leaving basic theoretical models (e.g., Hertz) to describe the contact response in the normal direction. A realistic description of the contact response may be crucial especially when investigating small strain ranges. Recent experimental inter-particle loading tests on gravel suggest that the classic contact models fail to reproduce certain mechanical features, especially when roughness is significant. Here, some of these experimental observations, including a softer response than the Hertz model under loading in the normal direction, and plasticity on unloading, are implemented in a DEM model for the simulation of small strain tests on railway ballast. The influence of these features on small strain stiffness is highlighted. A micromechanical analysis is carried out to show how each of the contact-level features introduced affects the macroscopic response.

Citation

Tolomeo, M., & McDowell, G. R. (2022). Implementation of real contact behaviour in the DEM modelling of triaxial tests on railway ballast. Powder Technology, 412, Article 118021. https://doi.org/10.1016/j.powtec.2022.118021

Journal Article Type	Article
Acceptance Date	Oct 10, 2022
Online Publication Date	Oct 18, 2022
Publication Date	Nov 1, 2022
Deposit Date	Oct 20, 2022
Publicly Available Date	Oct 20, 2022
Journal	Powder Technology
Print ISSN	0032-5910
Electronic ISSN	1873-328X
Publisher	Elsevier
Peer Reviewed	Peer Reviewed
Volume	412
Article Number	118021
DOI	https://doi.org/10.1016/j.powtec.2022.118021
Keywords	General Chemical Engineering
Public URL	https://nottingham-repository.worktribe.com/output/12619133
Publisher URL	https://www.sciencedirect.com/science/article/pii/S0032591022009020?via%3Dihub