There are a number of different cement types, referred to as CEM I up to and including CEM V, with a smaller or larger content of Portland cement and slag or fly ash.
- CEM I: Portland cement with a maximum of 5% other materials.
- CEM II: all kind of hybrids of Portland cement with for example slate, fly ash, slag… minimum 65% Portland cement.
- CEM III: blast furnace/Portland cement mixture in 3 classes: A, B and C; whereby CEM III/A contains the least (40%) and CEM III/C contains the most (90%) slag.
- CEM IV: Pozzolana cement varieties (this type of cement is not produced in Belgium).
- CEM V: composite cements, with mixtures of Portland cement, slag and Pozzolana.
Cement types are indicated by CEM followed by the number of the main sort in Roman numerals. After this there follows a forward slash with following this the letters A, B or C (= decreasing clinker content). The indication can be followed by a horizontal slash and a capital letter to indicate which component is used in addition to the Portland cement clinker.
Example: CEM II / B-V 32.5 R
Special cement types
Certain cement types are used for the production of concrete which is subjected to high levels of exposure or exceptional environmental conditions.
E.g. a damp environment (concrete that is continually moist and where granules are sensitive to alkali), acid environments (agricultural companies), concrete subjected to regular use of de-icing agents etc.
For this purpose, VVM has developed a CEM III/B 42.5N HS/NA:
- HS (Hoher Sulfatwiderstand): greater resistance to sulphates
- NA (Niedriger wirksamer Alkaligehalt): llow alkali content
With as main components 32% Portland cement clinker and 68% slag cement.