The main issues of building industry are rising demand for raw materials, energy resources, and related environmental problems such as high CO2 emissions. Therefore, alkali-activated materials have attracted significant interest in the scientific community due to its improved mechanical and durability properties, reduced energy consumption, and low environmental impact. The fresh state properties such as flow, setting time, rheology, and semi-adiabatic calorimetry of alkali-activated slag paste (AASP) mixes activated with sodium hydroxide (SH) or potassium hydroxide (PH) of 4 and 8 molarities were investigated in the present paper. The alkaline solution type and molarity significantly affected the fresh state properties of AASP mixes. PH-activated mixes showed better flow properties than SH-activated mixtures as they had lower yield stress and plastic viscosity. In addition, the increase in the concentration of either alkaline solution improved flow properties of paste mixes. The paste mixes containing PH showed prolonged setting times compared to the mixes activated with SH solution. Besides, the increment of PH molarity increased both initial and setting times, whereas an increase in molarity of SH slightly reduced the setting time of the paste mix. PH activated mixes displayed higher peak temperature compared to mixes containing SH for 8M, whereas the peak temperatures were comparable in 4M as revealed by semi-adiabatic test.
Anahtar Kelimeler: Blast furnace slag; Alkali-activation, Rheology, Semi-adiabatic, Setting time, Flowability
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