The efficiency of borax as an additive on properties of one-part fly ash/slag-based alkali-activated materials

Abstract

This paper characterizes the efficacy of borax on different properties of alkali-activated materials (AAMs). Fly ash (FA) and ground granulated blast slag (GGBS) were used as base substances at different ratios. The effects of borax on workability, compressive strength, efflorescence formation and crack resistance are the main ideas of the study. The results indicated the positive effects of borax on the properties of one-part fly ash/slag-based alkali-activated materials such as increasing workability and decreasing efflorescence. The microscopic images and scanning electron microscope (SEM) showed that the addition of borax reduced the cracks and a higher amount of slag made the samples denser with less unreacted raw materials, respectively. The compressive strength test results showed that borax had a detrimental impact at early ages with a positive effect at later ages. Binders with borax and 20-25% replacement of FA with GGBS were found to have the best performance when workability, compressive strength, efflorescence formation, and cracks on the samples were taken into account.

Keywords:

• Alkali activated binders
• geopolymers
• borax
• effloresce formation
• crack resistance
• microstructure
• workability

Disclosure statement

No potential conflict of interest was reported by the authors.

Authors’ contributions

Sajjad Yousefi Oderji wrote the manuscript and conducted all data, Prof. Chen Bing supervised the study and revised the manuscript and Ehsan Mohseni helped to do the analysis and improving the manuscript. All authors reviewed the final manuscript.

Additional information

Funding

This research work was financially supported by the National Natural Science Foundation of China, Grant No. 52278265.