Effects of Increasing Dosages of an Alkali-Free Accelerator on the Physical and Chemical Properties of a Hydrating Cement Paste

This study emphasizes a massive formation of a gel like material during setting of cement pastes. Furthermore, a mechanism of action of the alkali-free accelerator is proposed to initially promote a rapid precipitation of hydrated calcium sulphoaluminates both in crystalline and gel like form, and such a solid material, causing an increase of solid/water ratio, determines an increase in viscosity and a stiffening of cement mass, which results in a reduced final setting time.