Influence of packing density and water film thickness on early-age properties of cement pasteswith limestone filler and metakaolin

Supplementary cementitious materials (SCMs) affect the packing density and water film thickness (WFT) of blended cement paste. Herein, the effects of limestone filler (LF) and metakaolin (MK) on the packing density, WFT, flowability, heat of hydration, setting time and compressive strength of blended cement paste were studied. It was found that the addition of LF and MK would increase the packing density but whether it would increase the WFT is dependent on the change in solid surface area. Moreover, dispersion caused by finer particles stimulates the early hydration and reduces the setting time for the same SP dosage. However, the early compressive strength depends on the stimulation and dilution effects of SCM and retarding effect of SP.