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arXiv · 1007.0616

Janssen effect and the stability of quasi 2-D sandpiles

Fatemeh Ebrahimi·Tahereh Azizpour·Hamed Maleki
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Abstract

We present the results of three dimensional molecular dynamics study of global normal stresses in quasi two dimensional sandpiles formed by pouring mono dispersed cohesionless spherical grains into a vertical granular Hele-Shaw cell. We observe Janssen effect which is the phenomenon of pressure saturation at the bottom of the container. Simulation of cells with different thicknesses shows that the Janssen coefficient $\kappa$ is a function of the cell thickness. Dependence of global normal stresses as well as $\kappa$ on the friction coefficients between the grains ($\mu_p$) and with walls ($\mu_w$) are also studied. The results show that in the range of our simulations $\kappa$ usually increases with wall-grain friction coefficient. Meanwhile by increasing $\mu_p$ while the other system parameters are fixed, we witness a gradual increase in $\kappa$ to a parameter dependent maximal value.

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Fatemeh Ebrahimi, Tahereh Azizpour, Hamed Maleki. 2010-07-05. Janssen effect and the stability of quasi 2-D sandpiles. https://doi.org/10.1103/physreve.82.031302

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