Materials Science-Poland,
Journal Year:
2024,
Volume and Issue:
42(2), P. 125 - 142
Published: June 1, 2024
Abstract
Concrete
structures
are
extremely
vulnerable
to
fire
damage,
which
greatly
undermines
their
structural
strength
and
durability.
Recently,
there
has
been
a
concerted
effort
develop
sustainable
concrete
materials.
Geopolymer
(GPC)
is
promising
substitute
for
conventional
cement
due
its
use
of
recycled
However,
despite
the
positive
effect
it
on
environment,
GPC
susceptible
heat,
can
cause
deteriorate
over
time.
In
response
this
issue,
carbon-fiber
reinforced
polymer
(CFRP)
proposed
as
means
strengthening
heat-damaged
GPC.
This
study
aims
investigate
effectiveness
CFRP-strengthened
metakaolin-based
made
from
reclaimed
asphalt
pavement
(RAP)
aggregate.
Three
mixtures
were
used,
in
aggregate
was
substituted
with
RAP
at
0%,
25%,
50%
replacement
levels.
addition,
cylinders
tested
under
ambient
conditions
subjected
300°C.
The
results
indicated
that
substitution
25%
significantly
reduced
compressive
by
39.1%,
while
resulted
66.8%
decrease
compared
control
mixture.
CFRP
sheets
strengthen
specimens
proven
be
effective
increasing
resistance
heated
restoring
confinement
energy
original
state
before
reaching
ultimate
failure
point.
increased
strengths,
increases
ranging
87.7%
368.8%
26°C
58.8%
153.9%
300°C,
each
mixture’s
unstrengthened
specimen.
Applied Sciences,
Journal Year:
2024,
Volume and Issue:
14(5), P. 2081 - 2081
Published: March 1, 2024
Copper
slag
is
an
industrial
residue
with
a
large
unutilized
fraction.
This
study
presents
the
development
of
alkali-activated
composites
from
copper
named
Koranel®.
The
effects
metakaolinite,
ordinary
Portland
cement
(OPC)
and
surfactants
were
investigated.
reactivity
Koranel
potassium
silicate
solutions
molar
ratio
R
=
SiO2/K2O
varying
1
to
2.75,
0.25
intervals,
was
investigated
using
isothermal
calorimetry.
relatively
low
at
20
°C;
reaction
started
after
few
hours
silica
modulus,
several
weeks
highest
modulus.
substitution
by
OPC
(5
wt.%)
or
metakaolinite
(10–20
wt.%),
both
led
higher
heat
rate;
meanwhile,
addition
2
wt.%
polyethylene
glycol/2-methyl
2,4
pentanediol
delayed
time
in
system
containing
metakaolinite.
Raising
curing
temperature
°C
80
shortened
setting
reactive
systems,
days
almost
instantaneous,
opening
perspectives
for
their
application
production
prepreg
composite
materials.
use
carbon
fabric
as
reinforcement
matrix
materials
flexural
strength
reaching
88
MPa
elastic
modulus
about
19
GPa—interesting
engineering
applications
such
high-strength
lightweight
panels.
Materials Science-Poland,
Journal Year:
2024,
Volume and Issue:
42(2), P. 125 - 142
Published: June 1, 2024
Abstract
Concrete
structures
are
extremely
vulnerable
to
fire
damage,
which
greatly
undermines
their
structural
strength
and
durability.
Recently,
there
has
been
a
concerted
effort
develop
sustainable
concrete
materials.
Geopolymer
(GPC)
is
promising
substitute
for
conventional
cement
due
its
use
of
recycled
However,
despite
the
positive
effect
it
on
environment,
GPC
susceptible
heat,
can
cause
deteriorate
over
time.
In
response
this
issue,
carbon-fiber
reinforced
polymer
(CFRP)
proposed
as
means
strengthening
heat-damaged
GPC.
This
study
aims
investigate
effectiveness
CFRP-strengthened
metakaolin-based
made
from
reclaimed
asphalt
pavement
(RAP)
aggregate.
Three
mixtures
were
used,
in
aggregate
was
substituted
with
RAP
at
0%,
25%,
50%
replacement
levels.
addition,
cylinders
tested
under
ambient
conditions
subjected
300°C.
The
results
indicated
that
substitution
25%
significantly
reduced
compressive
by
39.1%,
while
resulted
66.8%
decrease
compared
control
mixture.
CFRP
sheets
strengthen
specimens
proven
be
effective
increasing
resistance
heated
restoring
confinement
energy
original
state
before
reaching
ultimate
failure
point.
increased
strengths,
increases
ranging
87.7%
368.8%
26°C
58.8%
153.9%
300°C,
each
mixture’s
unstrengthened
specimen.
