Effect of Nano-TiO2 addition on the hydration and hardening process of sulphoaluminate cement

Abstract

The influences of nano-TiO2 on the setting time, hydration process, hydration productsand morphology of sulphoaluminate cement were studied by Vicat apparatus, isothermal calorimetry, X-raydiffraction (XRD), thermal analysis and scanning electron microscopy (SEM). The experimental results showthat the incorporation of nano-TiO2 can obviously promote the setting and hardening process of sulphoaluminatecement, and shorten the interval between the initial and final setting time, the hydration induction period ofsulphoaluminate cement is significantly shortened and the acceleration period begins immediately, but thehydration exothermic rate at hydration stationary phase is not obviously impacted. The nano-TiO2 additives haveinfluence on the formation rate and degree of crystallinity, but do not affect the type of hydration process. Thestructure of hydration products is compact at middle age, but their content and microstructure do not change.