Use of Graphene in Ambient-Cured Slag-Fly Ash-Based Geopolymer Concrete

The durability performance of geopolymer concrete against severe environmental conditions is important for implementing geopolymer binders as alternatives to ordinary portland cement (OPC). In this experimental investigation, the impact of adding graphene on the durability characteristics of geopolymer concrete was examined. Graphene was added at 0.5% by weight of aluminosilicate precur-sors in geopolymer concrete. Permeability, salt ponding, capillary sorptivity, and immersion in chemical agents were performed to assess the durability characteristics of geopolymer concrete without and with graphene, which were also compared with the durability characteristics of OPC concrete without and with graphene. It was found that the addition of graphene in geopolymer concrete reduced the permeable voids by 12% and water absorption by 9%, and improved the resistance against chloride penetration and sulfuric acid exposure. The compressive strength of geopolymer concrete increased by 20% with the addition of graphene. Also, an approxi-mately 70% reduction in the initial and final rate of water absorption was observed in geopolymer concrete with the addition of graphene.