Abstract
The aim of the present work is to study the effect of active belite on the hydration of C(4)A(3)(S) over bar and C(4)A (S) over bar. The results revealed that the active beta-C2S prevents the formation of crystalline ettringite and monosulfate hydrate as detected from the results of XRD. On the other side, the sulfoaluminate hydrates such as AFt and AFm were detected by using DSC technique. Gismondine C4Al8Si8O32 center dot 16H is formed from the reaction of beta-C2S or CSH with the liberated Al(OH)(3) from the hydration of C(4)A(3)(S) over bar. This phase was not detected with the other monosulfate mix C(4)A (S) over bar. This is mainly due to the absence of AH(3) during the hydration of C(4)A (S) over bar. The results of XRD patterns are in good agreement with those obtained from DSC thermograms.