Application of the discrete element method for the simulation of size effects in concrete samples

This study aims to determine the validity of the discrete element method in predicting the size effect of cylindrical concrete samples under compression. For this purpose, a series of simulations are carried out on a set of particle assemblies with different diameters and aspect ratios. A fixed particle-size distribution and a single set of model parameters are used for all numerical simulations. Using compressive peak stress, peak strain and stress-strain curve as reference, numerical results are compared with experimental observations. The discrete element model is shown to effectively reproduce the effect of aspect ratio on compressive properties. On the other hand, although the method succeeds to capture the so called 'wall effect', it fails to show good correspondence with experimental values due to the assumption of spherical particles. The effect of end friction is also addressed. These findings give insight into the scalability of discrete element models when used for the simulation of concrete material. (C) 2016 Elsevier Ltd. All rights reserved.