Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A micromechanical model of collapsing quicksand   The discrete element method constitutes a general class of modeling
techniques to simulate the microscopic behavior (i.e. at the particle scale) of
granular/soil materials. We present a contact dynamics method, accounting for
the cohesive nature of fine powders and soils. A modification of the model
adjusted to capture the essential physical processes underlying the dynamics of
generation and collapse of loose systems is able to simulate "quicksand"
behavior of a collapsing soil material, in particular of a specific type, which
we call "living quicksand". We investigate the penetration behavior of an
object for varying density of the material. We also investigate the dynamics of
the penetration process, by measuring the relation between the driving force
and the resulting velocity of the intruder, leading to a "power law" behavior
with exponent 1/2, i.e. a quadratic velocity dependence of the drag force on
the intruder.

37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int