Energy Science & Engineering,
Journal Year:
2024,
Volume and Issue:
12(11), P. 5316 - 5327
Published: Nov. 1, 2024
ABSTRACT
The
severe
deformation
of
the
surrounding
rock
coal
floor
in
Shanghaimiao
mining
area
is
affecting
safe,
efficient
production
mine
wells
this
region.
In
study,
heave
mechanism
and
control
roadway
were
investigated
through
laboratory
experiments,
field
research,
theoretical
analysis,
numerical
simulation,
on‐site
testing.
results
showed
that
main
reason
for
serious
damage
to
was
low
strength
floor,
exacerbated
by
support
strength,
hydraulic
effects,
impact.
A
mechanical
model
asymmetric
established,
it
found
stability
positively
correlated
with
type,
stress
concentration
coefficients
on
two
sides
roadway,
burial
depth,
whereas
negatively
cohesive
force
internal
friction
angle
mass.
Expressions
upward
resultant
R
K
K′
both
derived.
a
FLAC3D
simulation
analysis
peak
front
working
face
36
MPa,
factor
3.7.
After
reinforced,
remarkably
reduced,
maximum
value
approximately
600
mm,
became
somewhat
asymmetric.
Finally,
double‐seal
floor‐reinforcing
“inverted
arch”
technique
proposed
tested
on‐site.
new
system
could
efficiently
stably
roadway.
International Journal of Mining Science and Technology,
Journal Year:
2024,
Volume and Issue:
34(4), P. 521 - 530
Published: April 1, 2024
Acoustic
emission
(AE)
localization
algorithms
based
on
homogeneous
media
or
single-velocity
are
less
accurate
when
applied
to
the
triaxial
experiments.
To
end,
a
robust
method
of
AE
source
using
refraction
path
is
proposed.
Firstly,
control
equation
established
according
sensor
coordinates
and
arrival
times.
Secondly,
considering
influence
time-difference-of-arrival
(TDOA)
errors,
residual
governing
calculated
estimate
weight.
Thirdly,
points
in
different
directions
solved
Snell's
law
orthogonal
constraints.
Finally,
iteratively
by
weighted
correction
terms.
The
feasibility
accuracy
proposed
verified
pencil-lead
breaking
simulation
results
show
that
new
almost
unaffected
ratio,
always
holds
more
stable
positioning
performance
than
traditional
under
ratios
scales
TDOA
outliers.
International Journal of Coal Science & Technology,
Journal Year:
2025,
Volume and Issue:
12(1)
Published: March 7, 2025
Abstract
This
study
focuses
on
steeply
inclined
and
extremely
thick
coal
seams
(SIETCS)
characterized
by
immense
thickness,
a
steep
inclination
of
(87°),
high
horizontal
stress.
The
geological
conditions
mining
technology
associated
with
SIETCS
differ
significantly
from
those
generally
seams,
resulting
in
notable
variations
roadway
stress
distributions.
On
have
predominantly
examined
the
impact
rock
layers
flanking
bursts,
limited
emphasis
roadways.
employs
comprehensive
methods,
integrating
numerical
simulations,
theoretical
analyses,
field
detections
to
investigate
distribution
mechanisms
burst-induced
vertical
damage,
subsequently
validated
situ.
is
minimal,
while
concentrated,
leading
formation
layered
crack
structures
(LCS)
that
distribute
above
below
Additionally,
elastic
energy
concentrates
within
LCS.
Axial
dynamic
compressive
tensile
along
LCS
diminish
its
stability,
readily
triggering
failure.
During
failure
process,
stored
released,
converting
into
kinetic
required
for
body
ejection
after
reaching
minimum
dissipative
energy,
ultimately
damage
On-site
detection
analysis
SIETCS,
historical
burst
data,
confirm
existence
role
inducing
damage.
research
establishes
essential
foundations
preventing
bursts
SIETCS.
International Journal of Coal Science & Technology,
Journal Year:
2025,
Volume and Issue:
12(1)
Published: March 14, 2025
Abstract
The
formation
of
coalesced
fractures
critically
alters
the
mechanical
properties
surrounding
virgin
material,
significantly
changing
stress
distribution
and
deformation
behavior
rock
mass.
However,
understanding
generation
mechanism
accurate
prediction
fracture
growth
remain
challenging
in
many
engineering
projects.
Despite,
wide
range
conventional
approaches
including
field
investigations,
laboratory-scale
tests,
numerical
modeling,
complex
geological
conditions
hinder
their
determination.
This
study
introduces
a
new
robust
cost-effective
holistic
geophysical
approach
to
determine
propagation
predict
failure
coal-rock
masses
at
laboratory
scale
applicable
across
scales.
proposed
combines
mechanics
Acoustic
Emission
(AE)
testing
systems
make
useful
correlation
between
AE
source
parameters
kinetics.
analyzes
spatiotemporal
events
elucidate
evolution
patterns
specimens
from
mining
project.
Results
showed
dense
fracturing
networks
within
coal
due
higher
density,
compaction,
strength
compared
samples.
is
indicated
by
peak
acoustic
80%–100%
load
versus
minimal
0–15%
load.
Simulated
closely
matched
observed
events,
identifying
key
lineaments
(macro-cracks)
representing
transition
microcracks
macro-fractures.
convergence
these
intensely
deformed
zones
prone
failure,
consistent
with
previous
investigations.
describing
critical
damage
revealed
an
inverse
relationship
event
magnitude.
At
roughly
70%
σ
max
,
dramatic
fall
seen
shift
small-scale
large-scale
microfractures,
ultimately
leading
catastrophic
Furthermore,
Single
Link
Cluster
(SLC)
analysis
demonstrated
strong
among
spatial
length
(ξ)
information
entropy
(
H
).
Both
increased
onset
loading
fluctuated
proximity
ultimate
failure.
Using
micro-crack
density
criterion
3D-crack
theory,
changes
above
verified
cracks
transformation
process.
These
findings
that,
approaches,
can
improve
disaster
control
management
plans,
failures,
save
lives
global
projects
when
applied
field-scale
studies.
Frontiers in Earth Science,
Journal Year:
2025,
Volume and Issue:
13
Published: April 3, 2025
The
control
of
mining-induced
seismicity
caused
by
hard
and
extremely
thick
rock
stratum
(HETRS)
has
become
an
important
topic
in
more
coal
mines.
This
study
investigates
the
mechanisms
through
a
discrete
element
numerical
model
(UDEC-Trigon)
calibrated
with
field
data
from
Dongtan
Coal
Mine,
China.
failure
process
HETRS
was
categorized
into
three
stages:
deformation
(Stage
I),
initial
fracture
II),
periodic
III).
In
stage,
change
vertical
displacement
is
4.33
m,
stress
26.21
MPa,
seismic
energy
1.91E8
J.
values
during
are
largest.
A
novel
method
developed
to
dynamically
track
events,
identifying
tensile
failures
central
shear
along
interfaces.
total
decrement
gravitational
potential
2.27E10J.
increment
dissipation
energy,
plastic
strain
1.16E9J,
1.49E9J
2.84E10J.
Therefore,
addition
elastic
also
main
source
energy.
comes
fractured
strata
as
well
surrounding
rock.
results
provide
unique
perspective
understand
mechanism
triggered
HETRS.
