Influence OF Contact Parameters on Fabric Evolution in Triaxial DEM Simulations of Cohesionless Materials

Abstract Discrete element modeling (DEM) is a useful tool for linking the global soil response to the underlying particle-level interactions. The behavior of the simulated material is strongly influenced by the interparticle friction and rolling resistance coefficients. A parametric study is conducted to investigate the effect of these parameters on the drained triaxial compression response of a poorly-graded granular material. Results show a strong relationship between the interparticle friction coefficient and the mobilized peak and residual strengths, initial stiffness, and dilative response. The rolling resistance coefficient has an increasing effect on the behavior as the interparticle friction coefficient is increased, indicating a coupled effect. Low values of the friction and rolling resistance coefficients result in a dense contact network while higher values yield an anisotropic fabric featuring a sparse contact network consisting of strong vertical columns.