Investigation of the Critical State in Soil Mechanics Using DEM

Journal Article · Thu Jun 18 04:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3179884· OSTI ID:21316819

Pena, Andres A ^[1]; Garcia-Rojo, Ramon ^[2]; Alonso-Marroquin, Fernando ^[3]; Herrmann, Hans J ^[4]

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1. Bilfinger Berger GmbH, Gustav-Nachtigal 3, 65915 Wiesbaden (Germany)
2. EPCOS, Avda. Jose Ortega y Gasset 173, 29006 Malaga (Spain)
3. MoSCoS, School of Mathematics and Physics, University of Queensland, St. Lucia, Qld. 4067 (Australia)
4. Departamento de Fisica, Universidade Federal do Ceara, 60451-970 Fortaleza, Ceara (Brazil)

The existence and uniqueness of the so-called critical state in soil mechanics is validated in our DEM simulations of irregular polygonal particles. For different particle shape characteristics, the critical state is independent of the initial stress and density conditions. We retain low stress levels, since we do not take into account the crushing of particles. In biaxial test simulations isotropic particles evolve toward a limiting state in which the system reaches a critical void ratio and deforms with constant volume, deviatoric stress, fabric anisotropy, and mechanical coordination number. The last one has been found to be the first variable to attain a critical value making possible for the rest of micro-and-macro-mechanical variables the convergence to the critical state. In periodic shear cell tests, for large shear deformations samples with anisotropic particles reach at the macro-mechanical level the same critical value for both shear force and void ratio. At the micro-mechanical level the components of the stress tensor, the fabric tensor and the inertia tensor of the particles also reach the same stationary state. By varying the aspect ratio of the particles we stated the strong influence of particle shape anisotropy on the parameters that the granular packing attained at the critical state.

• OSTI ID: 21316819
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1145; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANISOTROPY
ASPECT RATIO
COORDINATION NUMBER
CRUSHING
DEFORMATION
DENSITY
PARTICLES
PERIODICITY
RHEOLOGY
SHAPE
SHEAR
SOIL MECHANICS
SOILS
STRESSES
TENSORS
VOIDS