Influence of mineral additives on the packing density of ternary mix

The effect of fly ash, rice husk ash, metakaolin, ultra-fine slag on the packing density of ternary mix was studied in this paper, using Puntke’s method of particle packing. The addition of these mineral additives, whose particle size is lower than that of the Ordinary Portland Cement, improves the packing density of cement, by filling the voids between the cement grains, which results in increased compressive strength of concrete. The main aim of this research was to increase the packing density by replacement of cement with fine materials. Cement replacement was carried out from 10% to 40% in steps of 5%. Many combinations were tested and results showed that a maximum packing density of 0.586 was achieved at 75% cement content along with fl y ash and ultra-fine slag, without addition of the superplasticizer. Addition of superplasticizer further increased the packing at lower water to binder ratio.