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.
International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2022,
Номер
46(8), С. 1383 - 1408
Опубликована: Фев. 27, 2022
Abstract
The
last
several
decades
have
seen
a
surge
of
papers
dealing
with
analytical
and
semi‐analytical
solutions
to
the
problem
one‐dimensional
consolidation
soils.
But
rarely
has
any
these
contributions
focused
on
time
scales
arising
from
combined
primary
secondary
compression.
Primary
compression
always
been
attributed
dissipation
excess
pore
pressure
as
fluid
is
expelled
soil
skeleton
drainage
boundaries.
However,
there
schools
thought
when
it
comes
process
governing
In
this
paper,
we
attribute
following
processes
occurring
either
individually
or
in
combination:
(a)
rate‐dependent
(viscoplastic)
constitutive
response
skeleton;
(b)
existence
scale
system
that
expels
smaller‐scale
pores
larger‐scale
pores;
(c)
delayed
due
creep
Bjerrum's
concept
consolidation.
Contributions
present
work
include
closed‐form
soils
one
dimension,
well
quantitative
analysis
involved
such
coupled
hydromechanical
processes.
International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2022,
Номер
46(13), С. 2535 - 2560
Опубликована: Июль 10, 2022
Abstract
The
node‐based
smoothed
particle
finite
element
method
(NS‐PFEM)
offers
high
computational
efficiency
but
is
numerically
unstable
due
to
possible
spurious
low‐energy
mode
in
direct
nodal
integration
(NI).
Moreover,
the
NS‐PFEM
has
not
been
applied
hydromechanical
coupled
analysis.
This
study
proposes
an
implicit
stabilised
T3
element‐based
(stabilised
[SNS‐PFEM])
for
solving
fully
geotechnical
problems
that
(1)
adopts
stable
NI
based
on
multiple
stress
points
over
smooth
domain
resolve
instability
of
NS‐PFEM,
(2)
implements
polynomial
pressure
projection
(PPP)
technique
framework
cure
pore
oscillation
undrained
or
incompressible
limit
and
(3)
expresses
assembling
coefficient
matrices
calculating
internal
force
SNS‐PFEM
with
PPP
as
closed
analytical
expressions,
guaranteeing
accuracy
efficiency.
Four
classical
benchmark
tests
(1D
Terzaghi's
consolidation,
Mandel's
problem,
2D
strip
footing
consolidation
foundation
a
vertical
cut)
are
simulated
compared
solutions
results
from
other
numerical
methods
validate
correctness
proposed
approach.
Finally,
penetration
into
soft
soil
investigated,
showing
outstanding
performance
approach
can
offer
large
deformation
problems.
All
demonstrate
capable
tracking
under
small
different
drainage
capacities.
International Journal for Numerical and Analytical Methods in Geomechanics,
Год журнала:
2023,
Номер
47(11), С. 2116 - 2135
Опубликована: Май 16, 2023
Abstract
Existing
models
of
wellbore
stability
idealize
the
borehole
wall
as
either
a
perfectly
permeable
or
an
entirely
impermeable
surface.
The
widespread
observation
that
shale
allows
solvent
molecules
to
pass
through
but
impedes
solutes
suggests
should
be
regarded
non‐ideal
semi‐permeable
medium.
To
address
magnitude
and
rate
fluid
penetration
into
formation
when
is
exposed
non‐isothermal
drilling
quantitatively,
this
work
develops
analytical
solutions
for
undergoing
convective
cooling
far‐field
non‐hydrostatic
in
situ
stresses
framework
fully
coupled
thermoporoelasticity.
Integral
transform
load
decomposition
techniques
are
employed
facilitate
derivation
solutions.
results
show
that,
contrast
models,
model
predicts
significantly
different
stress
pore
pressure
fields.
transient
evolution
temperature,
pressure,
predominantly
governed
by
two
non‐dimensional
numbers:
Biot
number
B
i
newly
identified
π
f
characterizes
capability
transport
across
solid‐fluid
interface.
