Effects of Solid Activator and Fly Ash on Rheology and Thixotropy of One-Part Alkali-Activated Pastes

Abstract

Compared with conventional two-part alkali-activated materials (AAMs), one-part AAMs have several advantages, especially the simple production using only water similar to ordinary Portland cement. However, one-part AAMs are much less researched, especially in terms of rheology. Understanding the rheological behavior of such binders is a crucial step for their production, placement, and application in the construction industry. This paper studies the rheological properties of one-part AAMs through evaluating the dynamic yield stress, static yield stress, and thixotropic index. The effects of solid activator content, besides the effect of two types of fly ash (containing different amounts of carbonaceous impurities) with varying contents, are explored. The possible mechanisms are also discussed.