An experimentally validated DEM simulation of a monotonic triaxial test on railway ballast including the membrane boundary condition

Abstract

Discrete element modelling of a monotonic triaxial test is carried out with the aim of studying the stress-strain response of railway ballast in a large-scale tester. The latex membrane of the tester is modelled via a lattice of bonded particles to investigate the effects of membrane stiffness on the stress-strain response. The confining pressure application through the membrane is achieved via individual forces applied to the membrane particles, giving rise to a uniform, radially inward, equivalent stress. This modelling approach leads to a close agreement with published experimental data. A coarse-graining analysis of the numerical results is performed to study the evolution of the stress state in the numerical sample.

John P. Morrissey

Research Scientist in Granular Mechanics

My research interests include particulate mechanics, the Discrete Element Method (DEM) and other numerical simulation tools. I’m also interested in all things data and how to extract meaningful information from it.