Effect of Water to Geopolymer Solids Ratio on Properties of Fly Ash and Slag-Based One-Part Geopolymer Binders

Anil Sagar Srinivasa; K Swaminathan; Subhash C Yaragal

doi:10.55084/grinrey/RTM/978-81-964105-5-1_6

Authors

Anil Sagar Srinivasa Department of Civil Engineering, National Institute of Technology Karnataka, Surathkal, Mangalore, India
K Swaminathan Department of Civil Engineering, National Institute of Technology Karnataka, Surathkal, Mangalore, India
Subhash C Yaragal Department of Civil Engineering, National Institute of Technology Karnataka, Surathkal, Mangalore, India

DOI:

https://doi.org/10.55084/grinrey/RTM/978-81-964105-5-1_6

Keywords:

Alkali-activated materials, Compressive strength, geopolymer

Abstract

Geopolymer binders are claimed to be a satisfactory substitute for ordinary Portland cement (OPC) nowadays. These binders showcased their impracticalities in the execution part concerning transport, storage, and handling of strong alkaline solutions. This study describes a new "one-part" or "just add water" geopolymer binder which can be made in the same way that OPC is made by dry-mixing solid alumina-silica-rich materials, solid alkali activators, and free water. The flowability and compressive strength of one-part geopolymer binders produced from fly ash and slag were investigated as a function of the water to geopolymer solids (W/GS) ratio in this study. The W/GS ratio was considered as 0.25, 0.30, and 0.35. At each level of W/GS ratio, 25%, 50%, and 75% of the fly ash was substituted with ground granulated blast furnace slag by weight, where the solid activator content was maintained at 12% for all the mixes. The experimental and microstructural observation shows that the 50/50 fly ash/GGBS mixture at 0.30 W/GS had the best flowability and compressive strength, and their microstructure exhibited signs of being dense and compact compared to the other mixtures.