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LOW – CLINKER TERNARY CEMENTS
Performance and Standardization
Michel DELORT Association Technique de l’Industrie des Liants Hydrauliques
France
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Performance and standardization
Content
1. Historical background and objective
2. The pre-normative study 2.1 Content 2.2 Performance according to cement properties 2.3 Performance according to concrete properties 2.4 Performance according to concrete durability 2.5 Final remarks
3. Standardization 3.1 Composition limits 3.2 Classification
4. Conclusion
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Historical background and objective (1)
• Proposal from IBN (Belgium) to CEN/TC 51 – Dresden 2006
To standardize a «new type» of cement made from - Portland cement clinker: 30% to 64% - Blastfurnace slag: 30% to 50% - Limestone: 6% to 20%
Declared objective: To define and characterize a cement - having a low contribution to CO2 emissions - made from well-tried constituents and traditional manufacturing method - having a good workability - suitable for producing structural concrete of ordinary performance
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Historical background and objective (2)
• Acceptance of the IBN proposal by CEN/TC 51 under the following conditions [Resolution 445 (Dresden)]:
- To investigate the possible standardization of the cement
- To carry out a pre-normative study covering both performance and durability (based on test methods developed by CEN/TC 51 - TC 104/WG 12)
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Historical background and objective (3)
• Presentation of the first results to CEN/TC 51 - Montreux 2009
Positive evaluation to go further
Mandate to TC 51/WG 6 extended to cement compositions comprising Portland cement clinker (K), fly ash (V) or pozzolana (P) and limestone (L/LL) [Resolution 517 (Montreux)]
Further pre-normative research not within the remit of CEN/TC 51
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (1)
• Content: - Industrial and/or laboratory production of 13 different cement
compositions (K-S-L/LL) and (K-V/P-L/LL) – 17 cements - Test for conformity to mechanical, physical and chemical
requirements of EN 197-1 - Characterization of two concrete compositions
Concrete 1 Concrete 2 Strength class (N/mm2) C 20/25 C 35/45 Slump (mm) 110 – 130 70 – 90 Cement content (kg/m3) 300 340 W/C ratio 0,60 0,45
- Test of ternary cement concretes [carbonation, chloride diffusion, freeze-thaw (internal damage and scaling with de-icing agent), sulfate resistance] against common cement concretes from CEM I, CEM II/B-M (S-L), CEM II/B-LL and CEM III/B
7th International VDZ Congress 2013 25 – 27 Septembre 2013
K
S
L/LL
L/LL
S
K
90
80
70
60
50
S
40
30
20
10
7th International VDZ Congress 2013 25 – 27 Septembre 2013
COMPOSITION RANGE OF EXISTING COMMON CEMENTS Incorporating Portland cement clinker (K), blastfurnace slag (S) and limestone (L/LL)
and ternary compositions tested for CEN / TC51 (*)
(*) tests carried out by CRIC (Belgium) and Lafarge (France)
K
S
L/LL
L/LL
V/P
K
90
80
70
60
50
S
40
30
20
10
7th International VDZ Congress 2013 25 – 27 Septembre 2013
COMPOSITION RANGE OF EXISTING COMMON CEMENTS Incorporating Portland clinker (K), fly ash (V) or pozzolana (P) and limestone (L/LL)
and ternary compositions tested for CEN / TC51 (**)
(**) tests carried out by Lafarge (France)
Low-clinker ternary cements The pre-normative study (2)
• Performance according to cement properties
For physical properties, all results lie in the range of those obtained with tested common cements
For compressive strength: - 11 cements could be classified 32,5 or higher - 6 cements with a clinker content < 50% have failed to reach an adequate performance
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (3)
• Performance according to concrete physical and
mechanical properties
For shrinkage and creep, no significant differences between CEM I concretes and ternary cement concretes
For compressive strength, most cements allow to produce a C25/30 (or higher) concrete with 300 kg/m3 and a C35/45 (or higher) concrete with 340 kg/m3
Two 32,5 low-clinker ternary cement (50% K and 30% L) give poor results: C16/20 with 300 kg/m3 and C25/30 with 340 kg/m3
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (4)
• Performance according to concrete durability
Carbonation depth on concrete 1 (300 kg/m3) (EN 13295 - 56 days) - around 5 mm for CEM I and CEM II/B-M (S-LL) - around 10 mm or more when limestone > 25% (including CEM II/B-LL)
Chloride diffusion on concrete 2 (340 kg/m3) (NT Build 443) - low-clinker ternary cements provide results equivalent or better
than tested common cements - one exception for a cement containing 50% clinker, 20% pozzolana and 30% limestone
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (5)
• Performance according to concrete durability
Freeze-thaw - Internal damage on concrete 2 (340 kg/m3) (CEN/TR 15177)
- only CEM I concretes perform well - unexplained differences between CRIC and Lafarge on three ternary compositions - low-clinker ternary cements perform like CEM II and CEM III
Freeze-thaw - Scaling on concrete 2 (340 kg/m3) (CEN/TS 12390-9 - Slab test with adaptations)
- unexplained differences between CRIC and Lafarge - poor performance of low-clinker ternary cements: one to several
kg/m2 of scaled material
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (6)
• Performance according to concrete durability
Sulfate resistance (CUR 48) - all low-clinker ternary cements perform better than CEM I and
CEM II, some in the range of CEM III/B - blastfurnace slag seems to better contribute than fly ash and
pozzolana
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements The pre-normative study (7)
• Final remarks
Acceptable performance of low-clinker ternary cements in the range of CEM II/B or CEM III when clinker content > 30% and limestone content < 25%
Considering that a standard should comprise safety margin composition limits could be:
- for clinker ≥ 35% - for limestone ≤ 20%
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Standardization
• Based on the positive result of the pre-normative study, CEN/TC 51 decided to develop provisions, including composition limits and classification, for specifying low-clinker ternary cements within EN 197-1 or otherwise [Resolution 8/2012 (Athens)]
* Source: CEMBUREAU, the European Cement Association
7th International VDZ Congress 2013 25 – 27 Septembre 2013
POSSIBLE COMPOSITION LIMITS FOR LOW CLINKER TERNARY CEMENTS
Incorporating Portland clinker (K), blasfurnace slag (S) and limestone (L/LL)
7th International VDZ Congress 2013 25 – 27 Septembre 2013
L/LL
S
K
90
80
70
60
50
S
CEM III/C
CEM III/B
CEM III/A
CEM II/A-S
CEM II/B-S
CEM II/A-LL
CEM II/B-LL
CEM II/A-M (S-LL) CEM II/B-M (S-LL)
CEM II/C-M (S-LL)
CEM VI (S-LL)
L/LL K
90
80
70
60
50
S
V/P
POSSIBLE COMPOSITION LIMITS FOR LOW CLINKER TERNARY CEMENTS
Incorporating Portland clinker (K), fly ash (V) or pozzolana (P) and limestone (L/LL)
7th International VDZ Congress 2013 25 – 27 Septembre 2013
CEM II/C-M (V or P-LL)
CEM II/A-V or P
CEM II/B-V or P
CEM II/A-LL CEM II/B-LL
CEM II/A-M (V or P-LL)
CEM II/B-M (V or P-LL)
CEM IV/B
Low-clinker ternary cements A late additional request
• CEN/TC 51 could consider a late request for standardizing
compositions based on Portland cement clinker (K), blastfurnace slag (S) and fly ash (V)
because: - constituents are the most traditional ones - CEM II/B-M (S-V) and CEM V/A are known to perform well
but following presentation of positive results of a testing programme equivalent to the pre-normative study
7th International VDZ Congress 2013 25 – 27 Septembre 2013
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Conclusion
Fitness for use of given low-clinker ternary cements has been demonstrated
Low clinker ternary cements are worth of being standardized and can be incorporated in EN 197-1, the European standard on common cements
The procedure set-up by CEN/TC 51 could be applied to further innovative products
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Low-clinker ternary cements Standard and innovation
• A CEN Technical report under development
in CEN/TC 51 aims to describe the procedures for further applications i.e.
Further multi-constituent cements from
well-tried constituents Cements incorporating new constituents
and for which hardening is governed by CSH phases
Cements for which hardening could result from other phases than CSH
7th International VDZ Congress 2013 25 – 27 Septembre 2013
Thank you for your attention
Low-clinker ternary cements Performance and standardization
7th International VDZ Congress 2013 25 – 27 Septembre 2013