Composition of ground granulated blast-furnace slag and fly ash-based geopolymer activated by sodium silicate and sodium hydroxide solution: multi-response optimization using Response Surface Methodology

Abstract

Geopolymers are a class of new binder manufactured by activating aluminosilicate source materials in a highly alkaline medium. This binder is considered “environmentally friendly” due to the recycling of industrial waste sources such as fly ash and blast furnace slag. However, in order to be widely used, this binder has to ensure both quality and economic efficiency. This paper focuses on the optimization of the composition of ground granulated blast-furnace slag and fly ash-based geopolymers activated by sodium silicate and sodium hydroxide solutions. Statistical models are developed to predict the compressive strength and cost of 1 ton of binder using Response Surface Methodology (RSM). In this regard, the effects of three principal variables (%Na₂O, Ms and %GGBS) were investigated in which...