Modeling the shear response of granular materials with discrete element assemblages of sphere-clusters

Fernando E. Garcia, & Jonathan Bray

Published February 2019, SCEC Contribution #11683

Numerous high-performance computations of discrete element simulations of the direct-shear test investigate macroscopic and microscopic responses of granular materials. Volumetric dilation and mobilized friction angles are compared with spheres and sphere-clusters to investigate the influence of irregularly-shaped particles. Sphere-clusters are required to obtain realistic strengths and dilation rates. The absence of particle crushing in the simulations causes negligible void ratio reduction with increasing stress, but coordination number and initial stiffness are systematically stress-dependent. The development of the shear zone is shown through particle rotations and displacements, and the fluid-like nature of granular materials in shear is shown through particle velocities.

Key Words
Dilatancy; Direct shear test; Discrete element method; Homogenization; Sphere-cluster

Citation
Garcia, F. E., & Bray, J. (2019). Modeling the shear response of granular materials with discrete element assemblages of sphere-clusters. Computers and Geotechnics, 106, 99-107. doi: 10.1016/j.compgeo.2018.10.003.