In the production of cements with several main constituents the properties of the cements are determined by the reactivities and. particle size distributions of the cement components. The main factors affecting the strengths of cements with several main constituents are the mix composition of the cement and the reactivities and finenesses of the cement components. With cements which contain Blastfurnace slag and have a given composition the strength development is determined essentially by the overall fineness of the cement. Provided the overall fineness of the cement remains constant it is not possible, within industrially appropriate limits, to produce any cements with essentially different strength properties by combining cement components prepared with differing finenesses. With sulfate-optimized cements the water demand is affected mainly by the slope of the particle size distribution of the blended cement. The initial setting time of a cement with several main constituents is determined mot only by the clinker content and the reactivity and fineness of the clinker fraction, but also by the adjustment of the sulfate agent in the cement.
