There are many types of cement different in chemical composition and with different properties.
- Ordinary portland cement – This is the most commonly used cement. its properties render it useful in many building sites although it cannot be used where there is exposure to sulphates or ground water.
- Rapid hardening cement – its also known as high early strength cement. its strength develops quickly because of high tricalcium silicate content.
- Extra rapid hardening cement – it is achieved by mixing grinded calcium chloride with rapid hardening cement which catalyzes the cement properties.
- Low heat portland cement – low heat in cement in this case is achieved by reducing content of dicalcium silicate and tricalcium aluminate which reduces heat of hydration.
- Sulphate resisting cement – This has a low tri-calcium aluminate content inorder to avoid sulphate attack from outside the concrete.
- Portland blast furnace cement- this type of cement is made by intergrinding and mixing portland cement clinker with granulated blast furnace slag.
- super sulphated cement – is an interground mixture of 85% of basic blast furnace slag 10% gypsum and 5 % portalnd cement clinker. This has high resistance to sulphates.
- White & coloured portland cement – White cement is made from clay and consists of of little iron oxide and manganese oxide together with chalk or limestone. in coloured this is all done and pigments are added that dont have effects on strength.
- portland pozzolan cements – pozzolan is a siliceous or siliceous and aluminous material. addition of pozzolan does not add strnegth in early stages but in later stages.
- High alumina cement – this is made by heating a mixture of bauxite and limestone. The mixture melts and is cast into pigs and the ground to powder. this continuous wet curing is essential during this process it resists the gypsum water and chemical attack.
- Water proof cement – This is made by creating materials separate i.e calcium separate, aluminium separate and gypsum treated with acids like tannic to o.pc. at the time of clinker grinding.
- Expansive cement – This is cement that does not shrink due to loss of water. its made by a ratio of sulphoaluminate clinkers,stabilizer and o.p.c.
o.p.c = ordinary portland cement.