| Title |
Examining the Effect of Alkali Metals on the General Properties of Alkali-Activated Mortars |
| Authors |
지성준(Ji, Sung-Jun) ; 김규용(Kim, Gyu-Yong) ; 최병철(Choi, Byung-Cheol) ; 유하민(Eu, Ha-Min) ; 윤혜영(Youn, Hye-Young) ; 남정수(Nam, Jeong-Soo) |
| DOI |
https://doi.org/10.5659/JAIK.2025.41.5.281 |
| Keywords |
Alkali-activaed Materials; Activators; Alkali Metal Ion; Mechanical Properties; Gravimetric Analysis |
| Abstract |
This study examines the effects of LiOH, NaOH, and KOH as alkali activators on the mechanical and microstructural properties of
alkali-activated mortars, using binders made from GGBS, fly ash, and silica fume. Tests on flowability, setting time, compressive strength,
and shrinkage showed significant differences depending on the type of alkali metal ion. LiOH was found to delay polymerization, lower
compressive strength, and increase shrinkage due to the formation of insoluble Li₂SiO₃ and limited SiO₂ dissolution. In contrast, NaOH
produced the highest compressive strength by promoting effective geopolymerization, while KOH demonstrated moderate performance. SEM
analysis revealed that mortars with LiOH had more porosity and microcracks, whereas NaOH-based mortars had a denser and more uniform
matrix. XRD analysis also indicated that alkali metal ions do not significantly affect fly ash dissolution. These results highlight the strong
influence of alkali ion type on mortar performance and suggest that LiOH needs further refinement to improve its potential for sustainable
construction applications. |