Applied Sciences,
Journal Year:
2023,
Volume and Issue:
13(4), P. 2612 - 2612
Published: Feb. 17, 2023
The
brittleness
of
rock
is
known
to
be
an
important
property
that
affects
the
fragmentation
characteristics
in
mechanized
cutting.
As
interaction
between
cutting
tool
and
(i.e.,
cutter
forces,
efficiency,
s/p
ratio,
abrasivity)
during
mechanical
strongly
influenced
by
fragmentation,
tools
disc
pick
cutter)
experience
different
behaviors
depending
on
brittleness.
In
this
study,
relationships
abrasivity
rock,
efficiency
a
Tunnel
Boring
Machine
(TBM)
were
investigated
for
Korean
types.
was
calculated
mathematical
relations
uniaxial
compressive
Brazilian
tensile
strengths
rock.
evaluated
forces
specific
energy
from
linear
machine
(LCM)
test
Cerchar
index
(CAI)
test,
respectively.
results
show
significantly
correlated
with
CAI
values.
Consequently,
some
prediction
models
energy,
proposed
as
functions
Canadian Geotechnical Journal,
Journal Year:
2023,
Volume and Issue:
61(1), P. 59 - 74
Published: June 13, 2023
The
Maoxian
Tunnel
in
Sichuan,
China
has
experienced
significant
deformation
and
supporting
failure
the
surrounding
phyllite
rock.
To
address
this
problem,
on-site
engineering
geological
investigation
testing
methods
were
deployed
present
study
to
examine
characteristics
mechanism
of
tunnel.
Scanning
electron
microscopy,
rock
hydraulic
tests,
uniaxial
compressive
tests
used
investigate
mechanical
properties
rock,
mechanisms
underlying
deformation.
results
suggest
that
large
is
a
result
shear
expansion
progressive
soft
under
high
stress.
enhance
integrity
self-sustaining
ability
mass,
it
necessary
promptly
construct
support
structures
reinforce
Journal of Rock Mechanics and Geotechnical Engineering,
Journal Year:
2024,
Volume and Issue:
unknown
Published: April 1, 2024
In
situ
recycling
is
one
of
the
most
effective
methods
to
dispose
earth
pressure
balance
(EPB)
shield
waste
muck
with
residual
foaming
agents
high
moisture
content.
this
context,
response
surface
methodology
(RSM)
was
employed
quantify
effects
independent
variables,
including
flocculant
dosage,
defoamer
and
drying
mass
(MDM)
their
interactions
on
defoaming-flocculation-dewatering
indices.
The
polymeric
aluminum
chloride
(PACL)
hydroxy
silicone
oil-glycerol
polypropylene
ether
(H-G)
were
selected
as
defoamer.
contents
surfactants
foam
stabilizers
in
determined
using
proposed
empirical
equation.
defoaming
ratio,
antifoaming
turbidity,
content,
filtration
loss
fall
cone
penetration
depth
considered
dependent
variables.
accuracy
developed
RSM
models
verified
by
analysis
results
variance,
residuals,
paired
t-test.
Combined
desirability
approach,
an
optimal
mixing
ratio
0.078wt.%
PACL,
0.016wt.%
H-G,
27.882wt.%
MDM
recommended,
leading
a
98.34vol.%
for
foams
content
56.72wt.%
pressure-filtration
cakes.
Our
findings
demonstrated
be
able
provide
useful
guidance
prediction
optimization
indicators
EPB
metro
tunnel
construction
sites.
Journal of Rock Mechanics and Geotechnical Engineering,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Aug. 1, 2024
The
widespread
adoption
of
tunnel
boring
machines
(TBMs)
has
led
to
an
increased
focus
on
disc
cutter
wear,
including
both
normal
and
abnormal
types,
for
efficient
safe
TBM
excavation.
However,
wear
yet
be
thoroughly
investigated,
primarily
due
the
complexity
considering
mixed
ground
conditions
imbalance
in
number
instances
between
two
types
wear.
This
study
developed
a
prediction
model
conditions,
by
employing
interpretable
machine
learning
with
data
augmentation.
An
equivalent
elastic
modulus
was
used
consider
characteristics
obtained
from
65
cutterhead
intervention
(CHI)
reports
covering
hard
rock
sections.
With
balanced
training
dataset
augmentation,
extreme
gradient
boosting
(XGB)
delivered
acceptable
results
accuracy
0.94,
F1-score
0.808,
recall
0.8.
In
addition,
each
individual
exhibited
low
variability.
When
significant
improvement
observed
compared
when
it
not
used,
although
difference
marginal.
subsequent
interpretation
revealed
chamber
pressure,
installation
radius,
torque
as
contributors.
Specifically,
threshold
pressure
observed,
which
could
induce
also
explored
how
elevated
values
these
influential
contributors
correlate
proposed
offers
valuable
tool
planning
replacement
abnormally
worn
cutters,
enhancing
safety
efficiency
operations.
Applied Sciences,
Journal Year:
2023,
Volume and Issue:
13(4), P. 2612 - 2612
Published: Feb. 17, 2023
The
brittleness
of
rock
is
known
to
be
an
important
property
that
affects
the
fragmentation
characteristics
in
mechanized
cutting.
As
interaction
between
cutting
tool
and
(i.e.,
cutter
forces,
efficiency,
s/p
ratio,
abrasivity)
during
mechanical
strongly
influenced
by
fragmentation,
tools
disc
pick
cutter)
experience
different
behaviors
depending
on
brittleness.
In
this
study,
relationships
abrasivity
rock,
efficiency
a
Tunnel
Boring
Machine
(TBM)
were
investigated
for
Korean
types.
was
calculated
mathematical
relations
uniaxial
compressive
Brazilian
tensile
strengths
rock.
evaluated
forces
specific
energy
from
linear
machine
(LCM)
test
Cerchar
index
(CAI)
test,
respectively.
results
show
significantly
correlated
with
CAI
values.
Consequently,
some
prediction
models
energy,
proposed
as
functions
