Study of real granular assemblies

In the formulation of dry granular materials, the granular assembly can play a determining role in achieving the required final properties (rheological, mechanical, physical). To examine these properties, two indicators will be investigated: the compactness (C) and compressibility index (I) of the powders. Two different systems will be studied in this work. The first represents 3 components (fine, medium and large) with angular shapes; the second uses an acicular medium component, an angular fine component and an angular large component. The different systems were constituted with industrials particles. For each system, the compactness and the compressibility index of 21 different mixes will be investigated. The results will predict the behavior of particle mixtures according to mix and to the shape of particles. In order to predict the results of the various experiments, the relations between the proportions of the granular mixtures and the experimental values were investigated. Various statistical tools were used to categorize the mixtures, reveal the existence of relationships and determine what those relationships were. Data analysis of these results highlighted two parameters that strongly influence the compressibility of the mixtures. The size and the shape parameter are therefore required to explain the behaviors of these different mixtures.