Shear strength reduction in triaxial compression of confined granular materials due to vibrations using the discrete element method

Resumo

When subjected to external forces, the mechanical behavior of granular materials may range from static to dynamic. Unconfined granular beds, for example, are easily fluidized by vibratory loading. Under confinement, this type of material may also exhibit observable effects due to vibrations regarding their volumetric and strength behaviors. In this paper, the shear strength and dilatancy of dry confined granular materials subjected to vibrations are investigated using discrete element simulations of a triaxial cell. The material is first subjected to isotropic compression. Then, with controlled lateral stresses and imposed vertical motion, shear and compressive stresses are applied to a cubic sample. Additional harmonic displacements of the walls induce vertical and horizontal vibrations in the system during the shear tests. Finally, the impact of the amplitude, frequency, and direction of the vibrations on the angles of internal friction and dilatancy of the material is analyzed and compared to observations from the literature.