Particle size distribution, phase composition and cement properties

4 Particle size distribution, phase composition and cement properties 

Because the constituent phases of a cement are not equally easy to grind, different particle size fractions differ in composition. Gypsum, and its dehydration products, are concentrated in the finer fractions. Osbaeck and Jons (08) concluded that each 1% of gypsum contributed about 10m kg to the specific surface area in a typical case, some 15% of the total specific surface area is thus due to gypsum. The content of alite decreases, and that of belite increases, with increasing particle size (R12,G30), the contents of aluminate and ferrite phases being little affected. 

The depth of reaction of the cement grains after a given time has been 

---