Rheological behaviour and mechanical properties of Moroccan ternary binder's Portland clinker-fly ash-limestone

摘要

The objective of this study was to assess the effect of the variability of binary fly ash-limestone additions on the physical and rheological properties of milled composite cements to provide an optimal proportion in a cement plant. Three different proportions of fly ash (FA) are used: 5, 7 and 10 wt%. The effect of FA on rheology, setting time, volume expansion and compressive strength of composite cements has been studied. The results showed that the combination of limestone and FA could synergistically promote the rheological properties of ternary cements. Different behaviours were observed during the breakdown/buildup process of the structure. The use of FA has decreased the yield stress and increased the fluidity of the hydrated composite cements. The Vicat and Le-Chatelier test values have respected the limits prescribed by the standards. The compressive strengths were significantly increased from 2 to 90 days compared to the reference. An optimal proportion of FA in the composite cement was obtained which could provide convenient results on the industrial scale in a cement plant. (C) 2021 Elsevier Ltd. All rights reserved.