Limitations and perspectives of the micromechanical modelling of granular materials

The history of the micromechanical approach to the study of granular materials is briefly reviewed, and the main micromechanical contributions to the understanding of the mechanical behaviour of granular materials are reported. The difficulties in passing from the microscale to the macroscopic level are also discussed, as well as the capabilities of numerical models based on the distinct element method. The use of such numerical models for the analysis of engineering problems is discussed, by presenting different applications. A special emphasis is devoted to the procedures which are necessary for calibrating parameters.