1. Microscopic mechanism of particle detachment in granular materials subjected to suffusion in anisotropic stress states
- Author
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Wei Zhou, Antoine Wautier, Qirui Ma, Wuhan University [China], Risques, Ecosystèmes, Vulnérabilité, Environnement, Résilience (RECOVER), Aix Marseille Université (AMU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and This work was financially supported by the National Key R&D Program of China (Grant No. 2017YFC0404802), National Natural Science Foundation of China (Grant Nos. 51825905 and U1865204) and the China Scholarship Council (No. 201906270111). The numerical calculations in this paper have been done on the supercomputing system in the Supercomputing Center of Wuhan University.
- Subjects
Materials science ,Suffusion ,[SPI.GCIV.GEOTECH]Engineering Sciences [physics]/Civil Engineering/Géotechnique ,Lattice Boltzmann methods ,Mechanics ,Geotechnical Engineering and Engineering Geology ,Granular material ,Detachment mechanism ,Discrete element method ,Physics::Fluid Dynamics ,Stress (mechanics) ,[PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph] ,LBM-DEM ,Anisotropic stress ,[PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph] ,Earth and Planetary Sciences (miscellaneous) ,Fluid dynamics ,Particle ,Internal erosion ,Anisotropy ,Particle migration - Abstract
International audience; Suffusion refers to a special form of internal erosion characterized by the selective erosion of the finest particles of a soil under the action of an internal fluid flow. In this work, the microscopic mechanism of particle detachment in binary mixtures subjected to suffusion under different flow directions is analyzed. We use the coupled lattice Boltzmann method (LBM) and discrete element method (DEM) to simulate the suffusion process in a granular sample subjected to an anisotropic stress state. When the macro flow direction is aligned with the principal direction of compression, it is found that the fluid flow is more intense, which increases erosion. The stress anisotropy also influences the detachment direction that is not necessarily correlated with the macroscopic flow direction. The sample's anisotropic stress state is responsible for directional variations in microstructural properties during the suffusion under different flow directions. From a micro scale point of view, a contact sliding index P and a particle detachment index Δ are defined to demonstrate that fluid-induced sliding dominates for particles about to detach.
- Published
- 2021