Imaging Based Discrete Element Modeling Of Granular Assemblies
An imaging based Discrete Element Modeling (DEM) methodology is introduced to investigate effects of multiscale aggregate morphological properties on performances of granular assemblies, such as unbound aggregate layers used in railroad ballast and highway and airport pavement base courses. Coarse aggregates with four different angularity classes and three different surface texture roughness properties were quantified using the recently developed University of Illinois Aggregate Image Analyzer and then studied in a series of numerical simulation direct shear box tests using a DEM program. Effects of aggregate angularity and surface texture were presented as multiscale morphological properties on the strength of the granular assembly. Applications of the research methodology could potentially impact selection of construction aggregate properties and be used in the functional grading and manufacturing of crushed stone.
Keywords: Granular Materials, Image Processing, Numerical Analysis, Mechanical Testing