Cementitious materials other than Portland cement: supplementary cementitious materials, mineral components Portland cement additions

Although the terms ‘clinker’ and ‘Portland cement’ are quite well accepted, there are several other expressions used to designate the different materials that are blended with Portland cement clinker in cement plants or directly with Portland cement in concrete batching plants to produce hydraulic binders, that is, binders that harden with and in water. This is also true in languages other than English; for example, in French, the terminology is purposely vague: Baron and Ollivier (1995) make the following distinctions: • Secondary constituents are products incorporated at a level not greater than 5 per cent. It is not necessary to be precise about their nature, and the cement can still be sold as Portland cement.