NMR Studies of Cement Hydration
نویسنده
چکیده
The raw materials constituting the Portland cement are mainly lime, silica, alumina and iron oxide. During the manufacturing process, a glassy quasicrystalline clinker is formed which is ground, normally with addition of 1-3 wt% of CaSCU in the cement powder. This powder has four major constituents: 3 CaO"SiO2 (in cement chemists' notation C3S), 2 CaOSiO2 (C2S), 3 CaOAl2O3 (C3A) and 4 GaOAl2O3Fe2O3 (C4AF). While the proportions of these components vary, normally the cement powder consists of 60-70 wt% C, 17-25% S, 3-8% A and 0.5-6% F. Traces of MgO (0.1-4%) and alkalis (0.71.3), added sulphate SC>3(S) and bound water (H) are also found (1).
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