Effect of Nano-sized Titanium Dioxide on Early Age Hydration of Portland Cement

The effect of nano-scale non-reactive anatase titanium dioxide (TiO2) on early age hydration of cement was experimentally studied. Isothermal calorimetry was performed on cement pastes with two different particle sizes of TiO2 at replacement levels of 5, 7.5 and 10%. The addition of TiO2 to cement increased the heat of hydration and accelerated the rate of reaction at early stages of hydration. This increase was found to be proportional to the percentage addition and the fineness of TiO2. These results demonstrate that the addition of non-reactive nanoscale fillers could affect the rate of cement hydration by heterogeneous nucleation.