Sulphate supersulphated cement

Any attempt to understand the expansive process must thus consider the manner in which the deposition of the products affects the microstructure. The production of ettringite can cause expansion, but does not necessarily do so in a supersulphated cement (Section 9.2.9), much ettringite is formed, but there is no marked expansion. Comparable amounts of ettringite are reported to be formed when ordinary or sulphate-resisting Portland cements... 

Supersulphated cement is obtained from blast-furnace slag (80-85%), calcium sulphate (10-15%) and lime or Portland cement klinker (approximately 5%). After hardening, the strength comparable to that of ordinary Portland cement may be obtained with a considerably lower heat of hydration. Supersulphated cement may be used in various special concrete structures, particularly in situations where the action of acid fluids, sea water and oils should be expected e.g. for foundations and harbour structures. Mixing supersulphated cement with Portland cements and special treatment, such as accelerated hardening, is not possible. 

Supersulphated cement Supersulphated cement is a mixture of granulated blast furnace slag, calcium sulphate and a small content of activator (Portland cement or lime). It is a low pH material without CH, thus making it a potentially... 

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