Seminaire A - Theme 3 - Hydration of C3A in synthetic mixtures and in industrial portland cements

Abstract

The hydration of C3A and its solid s olutions with NazO has been followed by X-ray diffraction, scanning electron microscopy and electron probe microanalys is . These various methods have all shmm a decreasing early reacti- vity from the cubic form to the monoclinic form. The C3A-C3S intemction during hydration of C3A -C3S , gypsum mixtures has been put i n evidence by the formation of silicoaluminatcs around the C3A grains and by the hie;her degree of hydration in the C3S + ,cubic C3A mixtures . This interaction has been found again in industrial portl.and cements and t he silicoaluminatc has ~lso been observed in czs + C3A mixtures