Discrete element method to simulate the elastic behavior of 3D heterogeneous continuous media
Résumé
The paper aims to investigate the suitability of a discrete element method to simulate the elastic behavior of 3D heterogeneous continuous media. In the present work, the cohesion is modeled using beam elements introduced between each pair of particles in contact within the granular packing describing the investigated domain. Such an approach is an interesting alternative to classical continuous methods which enables to take into account more naturally discontinuities and damaging effects under various solicitations. Besides, the development of coupling strategies and efficient codes open new prospects due to ongoing reduction of calculation cost which was again recently the major drawback of discrete approaches. In the present work, we focus our studies on four points. We first take benefit of the new MULTICOR3D code developed in our laboratory to better define the representative volume element in terms of number of particles in the context of a homogeneous domain. Then, we investigate the definition of the stress tensor in the framework of simple heterogeneous configurations, namely a single cylindrical problem and a spherical inclusion one. The third objective is to highlight the suitability of the discrete element method to predict effective elastic coefficients for the same study cases and a large range of contrast of properties. Finally, we apply the cohesive discrete element approach to the case of an interpenetrating phase composite. In this last case, the influence of interfacial debonding effects are also considered and comparisons are done with experimental measures. Whatever the configuration of the heterogeneous medium, results in terms of stress fields and elastic coefficients are always in quite good agreement with the predictions given by other numerical approaches such as the finite element method and the fast Fourier based technique. (C) 2017 Elsevier Ltd. All rights reserved.