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Historical product range in South Africa. OPC - SABS 471RHC - SABS 471PBFC - SABS 636PC15 (SL or FA) - SABS 831PFAC - SABS 1466Masonry cements - no standard. . Cement extenders. SABS 1491 covers the quality of extenders for use at the mixerSlags from Iscor at Pretoria, Newcastle and Vanderbi
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1. New Cement Specification and Cement TypesRoad Pavements Forum Thursday 17 May 2001
2. Historical product range in South Africa OPC - SABS 471
RHC - SABS 471
PBFC - SABS 636
PC15 (SL or FA) - SABS 831
PFAC - SABS 1466
Masonry cements - no standard
3. Cement extenders SABS 1491 covers the quality of extenders for use at the mixer
Slags from Iscor at Pretoria, Newcastle and Vanderbijlpark were confirmed suitable through research
Fly ashes from Matla and Lethabo were also shown to meet requirements in extensive test programmes
4. SABS adopts new cement standards in 1996 SABS ENV 197-1 covering “Common Cements”
SABS ENV 413-1 covering “Masonry Cements”
6. Nomenclature CEM I, II, III, IV and V
I - Portland cement
II - Portland ……… cement
III - Blastfurnace cement
IV - Pozzolanic cement
V - Composite cement
A, B or C
indicates level of extender e.g. in CEM II
A is 6-20% and B is 21-35%
7. Nomenclature (cont.) Extender type
S - Blastfurnace slag
D - Silica fume
V or W - Fly ash
L - Limestone
M - Composite
8. Nomenclature (cont.) Strength grade
9. Nomenclature (cont.) Example CEM II B-W 42,5
Portland fly ash cement
Containing 21 to 35% fly ash
2-day-strength > 10 MPa
28-day-strength > 42,5 and < 62,5 MPa
10. Average 28-day compressive strength of OPC/CEM I 42,5
13. Factors to be considered when selecting cement type Cost of concrete
28-day compressive strength
Early compressive strength development
Ability to resist aggressive environment
Sensitivity to poor site practices and extent of supervision
Other properties (colour, heat development, control of ASR, etc.)
14. Cautionary remarks Do not extrapolate performance data for one cement as representing all cements
Do not assume that what is permitted in Europe will automatically work in SA
Ask for details of product performance from the manufacturer - check uniformity and performance relative to the issues of importance
Do not think that a SABS mark indicates that the cement is fit for any application
15. Thank you all for your attendance Good afternoon gentlemen
Good afternoon gentlemen