International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2024,
Номер
unknown
Опубликована: Сен. 19, 2024
ABSTRACT
We
present
a
double‐phase–field
framework
for
tensile
fracturing
processes
in
transversely
isotropic
rocks.
Two
distinct
phase‐field
variables
are
introduced
to
represent
smeared
approximations
of
fractures
along
the
weak
bedding
planes
and
through
anisotropic
rock
matrix,
respectively.
Driving
forces
that
control
fracture
propagation
constructed
as
stress‐based
formula
with
recently
developed
failure
criterion
distinguishes
two
modes
For
numerical
implementation,
we
adopt
staggered
integration
scheme
decouple
governing
equations
so
displacement
field
can
be
updated
sequence
given
loading
step.
The
finite
element
formulation
proposed
is
detail
this
paper
implemented
an
in‐house
code.
implementation
then
validated
by
reproducing
uniaxial
tension
test
results
Lyons
sandstone.
After
that,
conduct
simulations
on
pre‐notched
square
plate
loaded
demonstrate
features
framework.
Finally,
three‐point
bending
tests
Pengshui
shale
show
model
reproduce
force–displacement
curves
patterns
specimens
different
plane
orientations
observed
laboratory
experiments.
International Journal of Rock Mechanics and Mining Sciences,
Год журнала:
2024,
Номер
174, С. 105624 - 105624
Опубликована: Янв. 13, 2024
In
the
Mont
Terri
Rock
Laboratory
(Switzerland),
a
comprehensive
interdisciplinary
exploration
program
is
carried
out
to
increase
knowledge
about
long-term
coupled
hydraulic–mechanical
effects
in
Opalinus
Clay.
As
these
are
of
significant
interest
regarding
stability
and
integrity
potential
storage
facility
for
high
radioactive
waste,
"Influence
humidity
on
cyclic
longterm
deformations"
(CD-A)
experiment
aims
characterize
Clay,
especially
its
heterogeneous
sandy
facies,
investigate
evolution
water
content,
pressure
deformation
formation.
This
article
provides
an
overview
measurement
examinations
geologic
investigations
context
CD-A
experiment.
The
twin
niches
located
upper
facies
Clay
which
characterized
by
existence
different
subfacies
types
fault
zones.
contribution
focuses
detailed
characterization
claystone,
while
content.
Combined
geophysical
geological
during
first
two
years
after
excavation
have
been
out.
They
indicate
that
type
pre-existing
zones
do
not
affect
distribution
content
severely,
could
be
essential
finding
detection
procedures
level
waste
(HLW)
repositories.
Furthermore,
miniseismic
as
well
pulse
tests
clearly,
extent
damaged
zone
(EDZ)
strongly
depends
climatic
conditions
underground
galleries:
After
1.5
EDZ
permeability
much
more
pronounced
open
than
closed
twin.
Future
work
increased
process
understanding
based
verified
constitutive
model
system
considering
due
impact
geotechnical
boundary
heteregeneities.
Acta Geotechnica,
Год журнала:
2024,
Номер
19(10), С. 6691 - 6710
Опубликована: Апрель 25, 2024
Abstract
The
presence
of
abundant
clay
components
and
microporous
structure
in
shale
results
its
high
hydrophilicity,
making
a
water-rich
environment
inevitable
petroleum
exploration
projects.
Therefore,
it
is
crucial
to
consider
the
influence
bedding
structure,
moisture
content,
confining
pressure,
their
combined
effects
on
geomechanical
properties
shale.
This
article
aims
investigate
mechanical
deep
under
varying
water
content
conditions,
elucidate
failure
mode
mechanism
actual
engineering
scenarios,
explores
interplay
between
stress,
other
factors
properties.
evaluation
wellbore
stability
fracture
propagation
proposed
based
laboratory
experiments
using
triaxial
stress
strain
data,
along
with
application
energy
evolution
theory.
experimental
procedures
encompass
an
analysis
shale's
microscopic
as
well
anisotropic
compression
tests
conducted
different
contents
pressures.
demonstrate
that
exhibits
dense
pores
microstructure
displays
pronounced
characteristics
macrostructure.
within
these
pores,
situ
formation,
significantly
influences
anisotropy
decreases
increasing
but
performance
still
decreases.
Under
increase
pressure
some
extent
enhances
deformation
characteristics,
which
related
modes
However,
detrimental
effect
persists.
In
order
quantify
impact
factors,
this
study
utilizes
elastic
modulus
indicator
coupling
effect.
It
combines
curve
obtained
from
proposes
index
for
suitable
assessing
(the
called
SI
r
)
crack
expansion
brittleness
BI
).
calculation
reveal
that,
during
drilling
process,
excavating
parallel
direction
while
maintaining
low
yields
higher
value,
indicating
better
stability.
On
hand,
reservoir
fracturing,
fracturing
perpendicular
result
smaller
value.
approach
more
beneficial
network
engineering.
International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2022,
Номер
46(11), С. 2087 - 2114
Опубликована: Июнь 16, 2022
Abstract
This
paper
presents
a
combined
experimental‐modeling
effort
to
interpret
the
coupled
thermo‐hydro‐mechanical
behaviors
of
freezing
soil,
where
an
unconfined,
fully
saturated
clay
is
frozen
due
temperature
gradient.
By
leveraging
rich
experimental
data
from
microCT
images
and
measurements
taken
during
process,
we
examine
not
only
how
growth
ice
induces
volumetric
changes
soil
in
specimen
but
also
presence
propagation
fringe
front
may
evolve
anisotropy
effective
media
soil–ice
mixture
that
cannot
be
otherwise
captured
phenomenologically
isotropic
saturation‐dependent
critical
state
models
for
plasticity.
The
resultant
model
helpful
providing
qualitative
description
affects
responses
clayey
material,
provide
mean
generate
more
precise
predictions
heaving
ground.
International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2023,
Номер
48(4), С. 1018 - 1045
Опубликована: Дек. 27, 2023
Abstract
Solid
deformation
is
always
a
crucial
factor
of
gas
transport
in
sedimentary
rocks.
While
previous
studies
adopt
the
assumption
isotropic
poroelastic
deformation,
anisotropic
poroelastoplastic
rarely
considered,
despite
anisotropy
being
ubiquitous
property
natural
In
this
work,
an
poromechanical
model
established
to
analyze
matrix
porosity
and
apparent
permeability
evolutions
during
process
migration.
Using
thermodynamic
formulation
that
treats
fluid–solid
interface
as
independent
phase,
we
derive
rate
form
for
obtain
new
dissipation
function
contains
three
parts:
dissipations
from
solid
adsorption,
fluid
flow.
For
justify
rationality
adopted
model;
flow,
updated
can
be
substituted
into
sophisticated
models
full‐scale
analysis;
recently
developed
constitutive
appropriate
rocks
exhibiting
transverse
isotropy
both
elastic
plastic
responses
work.
Through
novel
stress‐point
simulation
incorporating
two
effective
stress
measures
adsorption
strain,
patterns
are
obtained,
which
fit
experimental
data
quite
well
cannot
reproduced
poroelasticity.
The
advantages
our
include
consistency
ability
employ
finite‐element‐based
formulation.
Finally,
initial‐boundary
value
problem
production
considering
plasticity
conducted,
effects
bedding
plane
different
highlighted.
