From Particle to Material Behavior: the Paths Chartered by Jean Biarez - Multiscale Geomechanics: From Soil to Engineering Projects - page 26

(contractancy), this phenomenon being more marked for strongly elongated arrays.
For the increment defined in the dilatancy domain, the arrays orientated in the
vertical direction show positive volumetric strain (dilatancy), this phenomenon
being more important for the strongly elongated arrays.
Figure 2.13. Analysis of the volumetric strain of the local arrays with respect to their
orientations and their degree of elongation (from [NGU 08])
2.6. Particle breakage
Many rockfill dams were built in the 1950s and 1960s. Constructed by
successive deposits of large-sized rocky blocks (whose diameter varied from around
10 cm to over 1 m), each layer was highly compacted before the next layer was
deposited. For these construction projects, it was elemental to take into account the
discrete nature of the material. Furthermore, an analysis of their deformation
revealed delayed strains that were mainly related to breakage of the blocks. Biarez