Partial replacement of manufactured sand with homologous granite powder in mortar: The effect on porosity and capillary water absorption

The granite powder (GP) was used to partially replace granite manufactured sand (GMS) to prepare cement mortar in this study. The hydration activity and the influence of GP on cement hydration were evaluated by isothermal calorimetry. The effects of GP substitution ratio on porosity, pore distribution and capillary water absorption coefficient were studied by vacuum saturation, X-ray computed tomography (X-CT), mercury intrusion porosimetry (MIP) and capillary water absorption, respectively. The relational equation between capillary water absorption coefficient and porosity was established through regression analysis. The results show that GP as an inert material can promote the hydration of cement. The porosity and capillary water absorption coefficient decrease with the increase of GP substitution ratio. The preliminary results reported in this paper open a new door for the sustainable application of GP in cementitious materials with improved performances.