Study of hydration mechanism of cement composite system with admixture of large amount of limestone powder

By means of XRD,DSC-TG and EDS methods,the hydration mechanism of cement composite system with large amount of limestone were studied.The results indicated that limestone could significantly promote the early hydration rate of cement,and the higher specific surface area of limestone,the more rapid early rate of hydration of cement could be observed.In the later hydration process,a few calcium carboaluminate hydrates(C 3 A.CaCO 3.11H 2 O) was formed because that limestone would take part of the reaction.Meanwhile,the amount of gel in the cement hydration paste that doped with limestone was lower than that in the pure cement hydration paste.