https://doi.org/10.1051/epjconf/202124914021
Quasistatic response of loose cohesive granular materials
Lab Navier, Univ Gustave Eiffel, École des Ponts, CNRS, 14-20 boulevard Newton, 77427 Champs-sur-Marne, France
* e-mail: walid.lammali@univ-eiffel.fr
** e-mail: jean-noel.roux@univ-eiffel.fr
*** e-mail: anh-minh.tang@enpc.fr
Published online: 7 June 2021
DEM-simulated model cohesive assemblies of spherical grains of diameter d, with contact tensile strength F0, once prepared in loose states, are quasistatically subjected to growing isotropic pressure P, and then to triaxial compression, maintaining lateral stresses σ2 = σ3 = P while increasing axial stress σ1 = P + q and strain є1. Reduced pressure P* = d2P/F0 varies from 0.1 (cohesion dominated case, for which systems typically equilibrate with solid fraction Ф ≃ 0.35), to large values for which the cohesionless behavior is retrieved. In triaxial compression, while the moderate strain response (є1 ~ 0.1) is influenced by initial coordination numbers and mesoscale heterogeneities, the approach to the critical state, as both q (deviator) and Ф steadily increase, gets slower for smaller P*. Critical ratio q/P strongly increases for decreasing P*, as roughly predicted in an “effective stress” scheme. Anomalously small elastic moduli are observed in the gel-like structures. While extensive geometric rearrangements take place, no shear banding is observed. Loose cohesive granular assemblies are thus capable of large quasistatic stable plastic strains and ductile rupture.
A video is available at https://doi.org/10.48448/vygx-k464
© The Authors, published by EDP Sciences, 2021
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
