Analytic laws for direct calibration of discrete element modeling of brittle elastic media using cohesive beam model

Abstract

In this study, a new methodology for the calibration of microscopic parameters for the cohesive beam model of discrete element method (DEM) applied to elastic brittle material is presented. This method enables the entry of material mechanical values directly into DEM simulations without any calibration steps. Several DEM simulations of tensile tests with different microscopic parameter values were carried out to generate a database of macroscopic parameter responses. This database was analyzed in order to deduce analytic laws by using nonlinear least square method. To validate the proposed calibration method, DEM simulations, which use the results of the calibrated microscopic parameters, were carried out. The macroscopic responses were compared to theoretical or experimental values. These validation tests were performed separately for two typical brittle elastic materials, i.e., soda-lime glass and alumina, with different shapes/sizes of discrete domain and various boundary conditions. Results between numerical and experimental values are in good accordance regarding the variability induced by this stochastic approach.