PRESENTATION ALUMINATE CEMENTS COMPARED IN A TERNATY SYSTEM

1. FAST
SET
,
HIGH
EARLY
STRENGTH
SHRINKAGE
COMPENSATED
CEMENT
BASED
ON
A
TERNARY
SYSTEM
ALUMINATE
CEMENTS,
CALCIUM
SULPHATE
AND
PORTLAND
CEMENT

2. Content
1. ternary
binder
2. Binder
3. aim
4. tes5ng
of
different
calcium
aluminate
5. results
6. discussion
7. conclusion

3. Ternary
binder

4. Aim
forma5on
of
early
e"ringite
a
fibrous
mineral
crystal
holding
32
water
molecules
3CaOŸAl2O3Ÿ3CaSO4Ÿ32H2O
C4A3Š

5. advantage
• fast
set
• quick
hardening
• high
ini5al
strength
• compensa5on
shrinkage
• rapid
drying
• cold
weather

6. binder
/
phases
Calcium
silicate
Calcium
aluminate
• CAC
High
alumina
cement
CA+C4AF
+C12A7+C2AS
• CSA
Calcium
sulpho
aluminate
C4A3Š
+C2AS
or
C2S
• ACA
Amorpous
calcium
aluminate
C12A7
+C2AS
• OPC
ordinary
Portlandcement
C3S(alite)+C2S(belite)
+C3A+C4AF4
Calcium
sulphate
• Anhydrite
calcium
sulphate
CaSO4

7. portlandcement
alumina
cement
quarz
slag
SiO2
CaO
Al2O3

8. Portland
cement
alumina
cement
mayenite
mono
calcium
aluminaat

9. test
• in
accordance
with
EN-­‐196
• 450
gram
binder
mixed
with
1350
gram
norm
sand
• W/C
:
0,5
• 0,3
%
of
organic
retarder
(added
when
se]ng
was
too
quick)
• prisms
16x4x4
cm
were
filled
and
de-­‐moulded
at
2
hours
• 8
parts
Portland
cement
(I.S
EN
197-­‐1:2011CEM
I
52.5R)
• 1
part
anhydrite
• 1
part
of
a
calcium
aluminate

10. results
mortars
were
tested
on
;
• se]ng
5me
• hydra5on
temperature
• compressive
/
flexural
strength,
• dimensional
stability

11. Vicat
se]ng
5me
min.
19:12
16:48
14:24
12:00
09:36
07:12
04:48
02:24
00:00
CSA
ACA
CAC
Begin
se]ng
End
se]ng

12. Temperature
on
hydra5on
C°
0
10
20
30
40
50
60
00:00:00
00:01:20
00:02:40
00:04:00
00:05:20
00:06:40
00:08:00
00:09:20
00:10:40
00:12:00
00:13:20
00:14:40
00:16:00
00:17:20
00:18:40
00:20:00
00:21:20
00:22:40
00:24:00
00:25:20
00:26:40
00:28:00
00:29:20
00:30:40
00:32:00
00:33:20
00:34:40
00:36:00
00:37:20
00:38:40
00:40:00
00:41:20
00:42:40
00:44:00
00:45:20
00:46:40
00:48:00
00:49:20
00:50:40
00:52:00
00:53:20
CSA
ACA
CAC

13. Compressive
strength
MPa
80
70
60
50
40
30
20
10
0
6
hours
24
hours
2
days
3
days
7
days
CSA
ACA
CAC

14. Flexural
strength
MPa
12
10
8
6
4
2
0
6
hours
24
hours
2
days
3
days
7
days
CSA
ACA
CAC

15. Shrinkage/Expansion
mm/m
0,10
0,09
0,08
0,07
0,06
0,05
0,04
0,03
0,02
0,01
0,00
6
hours
24
hours
2
days
3
days
7
days
CSA
ACA
CAC

16. discussion
• Portlandcement
is
the
dominant
part
of
the
binder
in
a
ternary
matrix.
• important
to
note
C3A
,
free
lime
,
type
and
amount
of
sulfate
• Calcium
sulfate
goes
in
solu5on
quickly
• it
counts
for
the
ini5al
strength
development
and
expansion
• type
and
amount
(anhydrite,
β
/
α
hemi-­‐hydrate,
gypsum)
influence
greatly
the
reac5vity
,
expansion
and
strength
development

17. discussion
• Calcium
aluminate
higher
ra5o
C/A
increase
reac5vity
• Mayenite
(C12A7)
is
the
most
rapid
phase
compared
to
other
calcium
aluminate
minerals
• main
hydrate
formed
C2AH8
• hexogonal
,
hydrates
rapidly
and
is
exothermic
• forms
with
Ca(OH)2
and
CaSO4
highest
amount
of
ehringite

18. conclusion
• an
op5mum
in
C/A
ra5o
and
sufficient
CaSO4
will
react
with
Ca(OH)2
(formed
at
hydra5on
of
Portland
cement)
to
form
acicular
3CaO·∙Al2O3·∙3CaSO4·∙32H2O
(eTringite/
C4A3S)
crystals
• high
ini5al
strength
and
posi5ve
expansion
• allows
working
at
low
temperatures
• ACA
gave
the
most
effec5ve
results
• even
at
half
the
dosage
• lihle
impact
on
se]ng
5me
was
no5ced
• ajer
48
hours
strength
was
compara5vely
in
pace
with
other
source
of
aluminates