Gypsum is added to the Portland cement clinker in the amount of 3 to 5% in the grinding phase as the binding rate regulator. When it comes to the hydration of cement, if sufficient amount of gypsum is added, fast cementation will not occur because gypsum by its presence reduces the solubility of tricalcium aluminate and thus slows down rapid reacti...

By Ilhan Bušatlić, Amna Karić