Effects of interparticle friction on the response of 3D cyclically compressed granular material

Abstract

We numerically study the effect of inter-particle friction coefficient on the response to cyclical pure shear of spherical particles in three dimensions. We focus on the rotations and translations of grains and look at the spatial distribution of these displacements as well as their probability distribution functions. We find that with increasing friction, the shear band becomes thinner and more pronounced. At low friction, the amplitude of particle rotations is homogeneously distributed in the system and is therefore mostly independent from both the affine and non-affine particle translations. In contrast, at high friction, the rotations are strongly localized in the shear zone. This work shows the importance of studying the effects of inter-particle friction on the response of granular materials to cyclic forcing, both for a better understanding of how rotations correlate to translations in sheared granular systems, and due to the relevance of cyclic forcing for most real-world applications in planetary science and industry.

A representation learning framework for detection and characterization of dead versus strain localization zones from pre- to post-failure

“…Second, many other fundamental kinematic events are governed by grain rotations, including rolling and sliding at the microscopic contact scale and mechanisms like force chain buckling and vortices at the mesoscopic scale [4-7, 11-13, 24, 29, 32]. Indeed recently uncovered kinematic details from more advanced measurement techniques have ignited renewed interest in the role of rotation in controlling plasticity, rheology and strength of granular materials [10,[67][68][69].…”

“…The pattern from s-LID, on the other hand, is capable of identifying multiple concurrent strain localization patterns: criss-crossing microbands can be observed for small neighborhood size s in the early pre-failure regime (e.g., s = 225, a ), while the shearband emerges for large s in the failure regime (e.g., s ≥ 900, e ). The role that grain rotations play in the development of strain localization is well-recognized [5,7,10,37,41,[66][67][68][69]81]. A recent study which completely suppressed grain rotations, however, underscored that grain rotations are a sufficient but not a necessary condition for strain localization [25].…”