The Nature of Quicksand
Despite the ubiquitous appearance of quicksand in adventure books and movies, its origin and physico-chemical behavior still represent controversial scientific issues in the fields of soil and fluid mechanics. It has been argued repeatedly that, because the density of sludge is typically larger than that of water, a person cannot fully submerge, and therefore cannot be really “swallowed” by any quick-sand.
We investigate the “quicksand” behavior of a collapsing suspension/soil material. A 2D contact dynamics model is proposed as a microscopic description to capture the essential physical processes underlying the dynamics of generation and collapse of the system.
Our physical model is validated with real data obtained from in situ measurements performed with a natural quicksand. We show that the shear strength behavior of our collapsing suspension/soil model is consistent with the behavior of this quicksand, for both the unperturbed and the collapsed phases of the material.