Basalt powder as a promising candidate material for improving the properties of fly ash geopolymer cement

Abstract

Recently, power plants’ manufacturing processes have evolved, and the amount of fly ash (FA) produced has gradually dropped. After years of investigation, FA has been used with a high rate of success. Therefore, FA, which is needed to manufacture geopolymers, may become more scarce and more expensive. To fill this gap, natural materials can be blended with FA to manufacture geopolymers. In this article, for the first time, a fascinating possibility has emerged for the possible application of natural basalt powder (BP) in FA geopolymer cement. As a partial replacement, several ratios of BP, from 2.5 % to 40 %, were mixed with FA. Geopolymer cement was then produced by activating both neat FA and those combined with BP. An inquiry was carried out to evaluate the influence of different ratios of BP on the flowability, compressive strength, environmental conditions resistance, transport properties, crystalline phases, hydration products, and microstructure of FA geopolymer cement cured in air and water. Regardless of whether the inclusion of BP decreased the flowability, the results showed that the inclusion of 2.5–20 % BP has a positive effect on improving the properties of FA geopolymer cement. The ideal ratio of BP was 10 %. Air curing was found more effective than water curing.