Direct observation of void evolution during cement hydration

Interaction of tartaric acid during hydration of Portland cement

Hydration of Ordinary Portland cement (OPC) in the presence of tartaric acid has been studied by using different techniques. Calorimetric studies have shown a rapid enhanced heat evolution within 5 min of hydration in presence of 1.0 wt% tartaric acid with a strong retardation of silicate phase hydration. DSC and X-ray diffraction studies have confirmed the formation of calcium tartarate hydrat...

NMR Studies of Cement Hydration

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 GaOAl2O3F...

Observation of dynamic crossover and dynamic heterogeneity in hydration water confined in aged cement paste

High resolution quasi-elastic neutron scattering is used to investigate the slow dynamics of hydration water confined in calcium silicate hydrate gel in an aged cement paste at supercooled temperatures. A super-Arrhenius to Arrhenius dynamic crossover of the average translational relaxation time 〈τ 〉 as a function of the inverse temperature is observed at TL = 231 ± 5 K, which coincides with a ...

Hydration of cement mixtures containing contaminants

Hydration Kinetics Model of Supersulfated Cement

Supersulfated cement, with higher waste utilization and less cement clinker is the inevitable trend of the development of green material in the rapid developed industrial era. For the wide use of supersulfated cement in our country, the hydration heat is analyzed in this paper. The hydration kinetic parameters are obtained from the hydration heat and hydration heat rate curves measured by the i...