Evaluation of particle simulation methods using aggregate angularity and slump tests

In this paper, three particle simulation methods were rigorously evaluated using several quantitative metrics to verify their feasibility for aggregate packing and mixing simulations in which determining the volumetric properties under multiple phases and conditions is essential. The physical properties and representative volume of each size of aggregate were determined by laboratory tests and image processing techniques. The sieve size sphere method, equivalent sphere method, and equivalent ellipsoid method were used with several combinations of friction coefficients to determine the significance of the particle simulation method on the dynamic aggregate behavior in discrete element method (DEM) simulations. The measured weight, height, diameter of the aggregate spread, and falling time duration from laboratory aggregate slump tests and aggregate angularity tests were compared to those from DEM simulations. The comparisons between the laboratory tests and simulations indicate that the aggregate angularity test and aggregate slump test were sufficiently accurate to capture the effect of the aggregate size on the dynamic behavior. No particle simulation method satisfied all of the conditions as well as the aggregate slump test and angularity test results, such as height, spread, weight, and simulation time; however, most of the particle simulation methods had good potential to simulate individual laboratory tests. Therefore, a more realistic particle simulation method that is capable of considering the morphological characteristics of aggregates should be developed to successfully perform packing and mixing simulations.