Dry
Quicksand
Reports that
travelers and even whole vehicles have instantaneously vanished by sand have
often been dismissed as products of fantasy. Rightly so? Our latest experiments
show that such a dry quicksand may exist, and that objects can sink up to many
diameters deep into very loose, fine sand.
Sand
supports weight. Force chains are known to play a prominent role therein. We
considerably weaken the force chain structure by letting air flow through very
fine sand. Even when the air is turned off and the bed has settled, the
prepared sand does not support weight: Balls sink into the sand up to five
diameters deep. We call this state of sand dry quick sand. The state is not to
be confused with the normal quick sand which is a mixture of sand, clay, and
water. The final depth the ball reaches scales linearly with its mass and above
a threshold mass, a sand jet is formed which
shoots sand straight and violently into the air. – Read all about it in the
See the web pages of the research group:
Physics of Fluids – Department of Science and Technology – University of Twente – The
More information:
See also our movies for the:
and our other publications in Nature and
Science.