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Beremend - 02/2010
Christophe Denayer
Milled limestone in concrete
LIME…The proven solution 2
1. Calcium Carbonate Fines (CCF)
• Milled limestone is CCF if :
Minimum 95% of CaCO3 (calcite, no chalk) Minimum 70% is passing sieve of 63µm Minimum 300 m²/kg Specific Surface Blaine
• CCF will have :
A filler-effect Chemical active as
accelerator
LIME…The proven solution 3
PREMIACAL®
• Calcite is a chemical mineral composed out of natural calcium carbonate (CaCO3) and which is cristallised in a rhomboedric system.
LIME…The proven solution 4
0
20
40
60
80
100
0.1 1 10 100 1000Particle Size (µm)
Cum
ula
tive (
%)
Cement without
limestone
Bosiljkov, Cem Concr Res 33 (2003) 1279-1286
1
2
3
12
3
Cement & CCF
CementCCF
CCF has a filler-effect
LIME…The proven solution 5
CCF influences the initial and final setting of cement
• Initial and final set are reduced.
• CCF is an activator of the hydration
Hawkins et al, PCA report (2003)
1:12
2:09
3:07
4:04
5:02
6:00
0 2 5 8Limestone content (wt. % )
Sett
ing z
one (
hour)
Initial set
Final set
Cement with
limestone filler
LIME…The proven solution 6
Rate of heat release of the pastes
• The rate of heat release in a mixture with CCF, is influenced during the first 10 hours.
LIME…The proven solution 7
What happens chemically during cement hydration ?
• Calcium aluminate hydration- without gypsum
- with gypsum (Portland cement) : 2 stepsC-A-H (‘Flash Set’)C3A + H2O
(1) C3A+ H2O + CSH2 C6AS3H32 (Ettringite)
C4ASH12 (Monosulfate)C3A + C6AS3H32(2)
• Calcium aluminate hydration- without gypsum
- with gypsum (Portland cement) : 2 stepsC-A-H (‘Flash Set’)C3A + H2O
(1) C3A+ H2O + CSH2 C6AS3H32 (Ettringite)
C4ASH12 (Monosulfate)C3A + C6AS3H32(2)
C-A-H (‘Flash Set’)C3A + H2O C-A-H (‘Flash Set’)C3A + H2O
(1) C3A+ H2O + CSH2 C6AS3H32 (Ettringite)(1) C3A+ H2O + CSH2 C6AS3H32 (Ettringite)C3A+ H2O + CSH2 C6AS3H32 (Ettringite)
C4ASH12 (Monosulfate)C3A + C6AS3H32(2) C4ASH12 (Monosulfate)C3A + C6AS3H32(2)
+ CaCO3 C3A.CaCO3.xH2O(Carboaluminate)
(1’)
+ 3 new routes
+ CaCO3 C3A.CaCO3.xH2O(Carboaluminate)
(1’)+ CaCO3 C3A.CaCO3.xH2O
(Carboaluminate)+ CaCO3 C3A.CaCO3.xH2O
(Carboaluminate)C3A.CaCO3.xH2O(Carboaluminate)
(1’)
+ 3 new routes
+ CaCO3
C3A.CaCO3.xH2O (Carboaluminate)
(2’)+ CaCO3
C3A.CaCO3.xH2O (Carboaluminate)
(2’)
C3A10%
C4AF10%
CSH2
5%C3S
50%
C2S25%
C3A
C-S-H
C3A
LIME…The proven solution 8
2. CCF for all types of concrete.
SCC
PAVING BLOCKSSTAIRS
PILLAR & BEAMS
Ready Mix Concrete
Semi-dry concrete
SCC-precast
Ready-mix concrete
LIME…The proven solution 9
3. semi-dry concrete
PAVING BLOCKSPIPESHOLLOWCORE FLOOR SLABS ROOF TILES
cement
water
cement
hydrates + free CaO
immediate after some H
after some D
setting of cement
network of cristals
• Cement is acting as a « filler ».
Replacement of 10 to 35%
of cement
• The most important targets for us in the concrete market are the producers of :
LIME…The proven solution 10
Example : mix-design for paving blocks
• Conclusion : Substitution of 51 kg of cement (261/50 -> approx. 20%) result in
costsavings of 600 HUF/m³ Maximum is 30 to 35% of cementreplacing -> 1200 HUF/m³
Price CEM I HUF/T 18000Price CCF HUF/T 6000
Mixture [unit] A B Ccement kg/m³ 311 261 211water l/m³ 109 109 109w/c 0,35 0,42 0,52CCF kg/m³ 50 1000/4 kg/m³ 867 867 8674/8 kg/m³ 1103 1103 1103
Price CEM+CCF/m³ HUF/m³ 5598 4998 4398Cost savings HUF/m³ 600 1200
LIME…The proven solution 11
Architectural reasons : less efflorescence & brighter
with CCF
without CCF
CCFCEM I
• Less risk on efflorescence, because of lower content of cement in mix-design
LIME…The proven solution 12
What in case of sulfate environment ?
• Respect miminum content of cement of EN 206 (XS-classes, …)
• Additional fines needed (=cement)? Replace cement with CCF
LIME…The proven solution 13
4. Ready-mix concrete
STAIRS
Ready Mix Concrete
Concrete screedCCFCEM I
LIME…The proven solution 14
French method : k-value = 0,25 (EN 206)
Among NF-EN 206
X0 XC1 XC2 XC3 XC4 XS1 XS2 XS3 XD1 XD2 XD3 XF1 XF2 XF3 XF4min. w / binder equivalent 0,65 0,65 0,60 0,60 0,55 0,55 0,50 0,60 0,55 0,50 0,60 0,55 0,55 0,45min. res. classe C 20/25 C 20/25 C 25/30 C 25/30 C 30/37 C 30/37 C 35/45 C 25/30 C 30/37 C 35/45 C 25/30 C 25/30 C 30/37 C 30/37min. equivalent binder 150 260 (*) 260 (*) 280 (*) 280 (*) 330 330 350 280 330 350 280 (*) 300 315 340min. % of air - - - - - - - - - - 4 4 4A/(A+C) 0,25 0,25 0,25 0,25 0,25 0,05 0,05 0,05 0,25 0,05 0,05 0,25 0,25 0,25 0,25
(*) 300 kg/m³ prestressed concreteA/(A+C) min eq bi A max C eq C min
unity kg/m³ kg/m³ kg/m³ kg/m³0,25 280 93 23 2570,05 330 17 4 326
280 257
93
0
50
100
150
200
250
300
350
400
1 2
LIME…The proven solution 15
5. Self compacting concrete (SCC)
1200835
675
820
350
350
250
175 175
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
conventional SCC
Water
Fillers
Cement
Sand
Aggregates
SCC
• Need for fillers in SCC
• MLS disposes a constant water-absorption, colour, …
LIME…The proven solution 16
Mix design of Okamura & Ouchi, corrected by NL
SCC mix-design in 9 steps :1. volume of air2. volume of coarse aggregates3. volume of fine aggregates4. volume of paste5. ratio w/p6. testing on mortar bars 7. testing on concrete8. calculation9. controlling
LIME…The proven solution 17
Vair -> V coarse aggr -> Vfine aggr -> V paste
• Assume : Vair = 2% or 0,020 m³ -> ➊
• Assume : 50% of rest-volume is used by coarse aggregates at their best stacked pile V coarse aggr = 0,5.(1-Vair).ρb / ρa (in m³) -> ➋
ρa = 2650 kg/m³ (specific weight of aggregates)
ρb = 1670 kg/m³ (best stacked weight of aggregates)
Remark : if 45%, use 0,45 in formula
• Assume : V fine aggr = 0,45 (1 - V coarse aggr - Vair)
We are reducing the quantity of fine aggregates to garantee that the influence of the fluidity of the paste will also be applicable on the mortar. [Assume 0,45 – could also be 0,40]
• V paste = 1 - V coarse aggr – Vfine aggr – Vair
LIME…The proven solution 18
powder
water
V
V
12
0
d
d
p
How to determine beta P of a powder
• Cement -> 0,9 till 1,4
• Milled limestone -> 0,8d
dd
2
21
2
LIME…The proven solution 19
w/p-ratio
• Water-powder ratio : Paste = powder + water
Powder = cement + addition• βp cement = 1,2 (CEM I 52,5 R)
• βp addition = 0,8 (milled limestone)• Assume relation cement/addition: 60/40 in volume• βp cement+addition = (0,6 x 1,2)+ (0,4 x 0,8) = 1,04
Water : w/c-ratio : (1,04 x 1,0)/(0,6 x 3,15) = 0,55
• Correction-factor for waterdemand of powder : – CWm (between 0,7 and 1,0) -> assume 0,85 (not definitif)
w/p-ratio = Vw/Vp = CWm. βp cement+addition = 0,884 -> ➎
1,2 liter water is needed for 1 liter of cement :
So 1,2 lw / 1,0 lc = (1,2x1,0) / (1,0x3,15) = 0,38
w/c-ratio without flow
1,04 liter water is needed for 1 liter of C+A :
So 1,04 lw / 0,6 lc = (1,04x1,0) / (0,6x3,15) = 0,55
to reduce the risk for segregation
LIME…The proven solution 20
Mortar mix-design (1)
• Mortar consist of Cement Addition Sand Water Admixtures No coarse aggregates
• Define 1500 ml of mortar : Assume : 45% or 675 ml = absolute volume of
sand So, 55% or 825 ml = paste
LIME…The proven solution 21
Mortar mix-design (2)
We know from earlier :• Beta p (C+A) = 1,04• CWm = 0,85• Vw/Vp = CWm. βp cement+addition = 0,884
Assume : • 45 % of mortar = sand -> 1500 ml x 0,45 = 675 ml• Ratio (Cement/Addition) = 60/40
Solution :• Vpaste = 1500 – 675 = 825 ml• Vw / Vp = Beta p (C+A) x CWm = 1,04 x 0,85 = 0,884• Vp = Vpaste /(1 + Vw / Vp) = 825 / (1+0,884) = 438 ml
Vcement = 0,6 x 438 = 263 ml Vaddition = 0,4 x 438 = 175 ml
• Vw = Vpaste – Vp = 387 ml
• We are looking for a just combination between
– watercontent (Vw / Vp) – admixtures (%)
s
% of admixtures [on powder content]
V density weightml T/m³ g
sand 675 2,65 1.789water 387 1 387cement 263 3,15 828milled limestone 175 2,17 380Total 1500 3.384
Mortar funnel test [s]
Mortar flow test [mm]
LIME…The proven solution 22
Mortar mix-design (3)
320
330
340
350
360
370
380
390
0 2 4 6 8 10 12
OK
[mm] – mortar flow test
1. Not OK, correct with– Raising admixtures : flow
(mm) will raise (a)– Raising CWm : more water in
mixture, less viscosity, less time (s) for empty the funnel. (b)
2. Not OK, correct with sand-ratio :
– Raising sand% : lower flow (mm) and higher time (s)
3. Other : – Change admixtures– Change cement/addition-
ratio– Change coarse aggregates
volume
4. Conclusion : we know CWm – % admixtures
– Vw – Vc- Va - Vfine aggr
[s] – mortar funnel test
a
b
Not OK, we can correct formula with1. Reducing/raising admixtures2. Correct CWm (reducing or raising)3. Other sand %4. Other changes
% of admixtures
7 s 11s
LIME…The proven solution 23
Concrete mix-design (1)
Coarse aggregates
Mortar :1. Fine aggregates
2. Paste = water + powder
• Vair = 2% or 0,020 m³ -> ➊
• Assume : 50% of rest-volume is used by coarse aggregates at their best stacked pile
– V coarse aggr = 0,5.(1-Vair).ρb / ρa (in m³) -> ➋
– ρa = 2650 kg/m³ (specific weight of aggregates)
– ρb = 1670 kg/m³ (best stacked weight of aggregates)
– Remark : if 45%, use 0,45 in formula
Abrams cone
V-funnel
LIME…The proven solution 24
Concrete mix-design (2)
Results in function of application :
Flow (mm) Time (s)
Wall 830 7
Pillar 780 8
Beam 780 8
Floor 720 11
If not OK :corrections with % admixt. and/or water (CWm)
Conclusion :
1. V paste = 1 - V coarse aggr – Vfine aggr ➌ – Vair -> ➍2. % admixtures
3. Final correction factor CWm
type0-4 0-8 0-16 0-32
A 270 390 515 600B 240 350 450 515C 60 105 150 195D 30 40 65 85E 30 40 75 95
(liters) 1,13 3,27 10,51 18,3
size aggregatesdimensions V-funnel in mm
Abrams cone
V-funnel
LIME…The proven solution 25
Calculation & controling
1. % of admixtures is defined (after concrete tests)
2. CWm is now defined (after concrete tests)
3. V coarse aggr & Vfine aggr & Vair are also known : ➊ ➋ ➌
4. V paste = 1 - V coarse aggr – Vfine aggr – Vair -> ➍
5. Vpowder = V paste / (1+Vw/Vp)
1. with Vw/Vp = CWm. βp cement+addition
6. Vw = V paste - Vp
7. Powder = cement + addition and the ratio C/A is known -> we can count the quantity of each powder
Do we respect EN 206 ? w/c ratio ? minimum content of cement for the environmental class
LIME…The proven solution 26
What you need in each laboratory is …
V-funnel
type0-4 0-8 0-16 0-32
A 270 390 515 600B 240 350 450 515C 60 105 150 195D 30 40 65 85E 30 40 75 95
(liters) 1,13 3,27 10,51 18,3
size aggregatesdimensions V-funnel in mm
Cone of Haegermann
Cone of Abrams
V-funnel for mortar test
V-funnel for concrete test
LIME…The proven solution 27
Other testmethods to characterize fresh SCC
• U-box
• L-box
• J-Ring
• Stability on sieve
• Orimet
U-box
Stability on sieve
J-ring
L-box
Orimet
LIME…The proven solution 28
SCC - applications
BEAMS
COLUMS - PILLARS
STAIRS
WALLS
Ready Mix Concrete
• PRECAST CONCRETE. Typical applications :
• READY-MIX CONCRETE .
LIME…The proven solution 29
Ask assistance by your superplasticizer-supplier
• MAPEI
• BASF : SP = glenium® (before Degussa, before Masterbuilders)
• SIKA : SP = viscocrete®
• CHRYSO : SP = premia®
Do not forget :
SCC is technically feasible due to the latest development of polycarboxylates
LIME…The proven solution 30
6. Carmeuse Europe supplies to 400 concrete plants
• 370 concrete plants in W-Europe (France, Belgium, NL)
• 30 concrete plants in Central Europe (CZ) :
1. HOLCIM CZ (ready-mix concrete : SCC, screed, architectural,..)
2. RIEDER BETON (SCC-pillar&beams)
3. DYWIDAG (SCC-pillar&beams)
4. ZPSV (SCC-pillar&beams)
5. Prefa Brno (paving blocks, pipes,…)
• HU : first clients
LIME…The proven solution 31
7. Scientific Review of MLS in concrete
LIME…The proven solution 32
•Thank you