Publication result detail

Mapping the effects of activator type and molarity on the rheology of alkali-activated slag using oscillation amplitude testing

MARKUSÍK, D.; SOKOLA, P.; BÍLEK, V.

Original Title

Mapping the effects of activator type and molarity on the rheology of alkali-activated slag using oscillation amplitude testing

English Title

Mapping the effects of activator type and molarity on the rheology of alkali-activated slag using oscillation amplitude testing

Type

WoS Article

Original Abstract

This study investigates the effects of activator type and concentration, namely sodium and potassium hydroxides, carbonates, and silicates, on the rheological behaviour of alkali activated slag pastes. Oscillation amplitude sweep tests in both strain- and stress-controlled modes were conducted to evaluate key parameters such as yield point and break point. Increasing activator concentration generally improved workability up to a threshold between 5 and 7.5 M, beyond which rheological properties deteriorated due to changes in microstructure and viscosity. This threshold was less pronounced for KOH and K2CO3. Alkali silicates exhibited the strongest plasticizing effect and, uniquely, shifted the viscoelastic nature of the pastes from solid-like to liquid-like (significantly increased loss factor). Complementary mini-slump and zeta potential tests supported the oscillatory findings and revealed limitations at extreme concentrations. The results highlight the distinct impacts of different combinations of Na+ and K+ cations and various anions on the rheology of alkali-activated slag pastes.

English abstract

This study investigates the effects of activator type and concentration, namely sodium and potassium hydroxides, carbonates, and silicates, on the rheological behaviour of alkali activated slag pastes. Oscillation amplitude sweep tests in both strain- and stress-controlled modes were conducted to evaluate key parameters such as yield point and break point. Increasing activator concentration generally improved workability up to a threshold between 5 and 7.5 M, beyond which rheological properties deteriorated due to changes in microstructure and viscosity. This threshold was less pronounced for KOH and K2CO3. Alkali silicates exhibited the strongest plasticizing effect and, uniquely, shifted the viscoelastic nature of the pastes from solid-like to liquid-like (significantly increased loss factor). Complementary mini-slump and zeta potential tests supported the oscillatory findings and revealed limitations at extreme concentrations. The results highlight the distinct impacts of different combinations of Na+ and K+ cations and various anions on the rheology of alkali-activated slag pastes.

Keywords

Alkali-activated slag, Rheology, Oscillatory measurement, Activator concentration, Activator type, Surface chemistry

Key words in English

Alkali-activated slag, Rheology, Oscillatory measurement, Activator concentration, Activator type, Surface chemistry

Authors

MARKUSÍK, D.; SOKOLA, P.; BÍLEK, V.

RIV year

2026

Released

01.03.2026

Publisher

Elsevier

Periodical

Open Ceramics

Volume

25

Number

March

State

United Kingdom of Great Britain and Northern Ireland

Pages count

13

URL

https://www.sciencedirect.com/science/article/pii/S2666539526000131?via%3Dihub

BibTex

@article{BUT201560,
  author="{} and David {Markusík} and  {} and Patrik {Sokola} and  {} and Vlastimil {Bílek}",
  title="Mapping the effects of activator type and molarity on the rheology of alkali-activated slag using oscillation amplitude testing",
  journal="Open Ceramics",
  year="2026",
  volume="25",
  number="March",
  pages="13",
  doi="10.1016/j.oceram.2026.100920",
  url="https://www.sciencedirect.com/science/article/pii/S2666539526000131?via%3Dihub"
}