Distinct element modeling of coupled chemo-mechanical compaction of rock salt
Date
2007
Authors
Min, Ki-Bok
Niemeijer, A.
Elsworth, Derek
Marone, C.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Conference paper
Citation
Euro-conference of Rock Physics and thermo-hydro-mechanical processes in rocks / Ettore Majorana Foundation and Centre for Scientific Culture, 25–30 September, 2007: pp.45-46
Statement of Responsibility
Conference Name
Euro-conference of Rock Physics and thermo-hydro-mechanical processes in rocks (29th : 2007 : Erice, Italy)
Abstract
The chemically-mediated compaction of rock salt is represented as a problem in
granular mechanics using a distinct element model. The model follows the motion of
the interacting particles by combining conservation of momentum with a contact law
between particles, which accounts for the time dependent closure due to pressure
solution via a viscous resistance (Fig.1a for verification). Attributes of the model are
explored through a variety of studies to explore the effect of packing, (i.e., regular
versus random packing), and size distribution of granular particles. The results show
that random packing, which is typically the case for natural compaction, allows for
significantly larger pressure solution-induced viscoelastic displacement than regular
packing, a frequently-used generic model for pressure solution, due mainly to the
increased contact areas between particles (Fig.1b). A range of diameter distributions
of the particles tested to investigate the dependency on size distribution show that size
distribution is an important factor in inducing and triggering pressure solution. The
code is used to explore effects apparent in laboratory experiments on granular
mixtures of salt, in which pressure solution is known to operate at rapid rates under
room temperature conditions. The rock salt was crushed and sieved to obtain 6 grain
size fraction ranging from 38 – 212 μm to investigate the effects of grain size and
grain size distribution. The experiments were performed in a steel pressure vessel
inside a biaxial loading frame under both constant stress and constant strain (stress
relaxation) conditions with controlled pore pressure and confining pressure.
School/Discipline
School of Civil, Environmental and Mining Engineering