A review of geopolymer concrete: An eco-friendly substitute for traditional concrete

Portland cement is an essential component in construction. Nevertheless, its manufacturing process is energy-demanding and produces a lot of CO2 and greenhouse gases which are the major sources of global warming. With the increasing demand of concrete materials, the environmental footprint of Portland cement is expected to increase. Therefore, geopolymer concrete has been introduced as a sustainable cementitious material which employs aluminosilicate-containing industrial by-products like fly ash, ground granulated blast furnace slag, rice husk ash, and clay. These aluminosilicate by-products when activated by alkaline solutions form geopolymer binder which uses much less energy and emits much less carbon emissions than Portland cement. Geopolymer concrete possesses several benefits such as high compressive strength, great durability, as well as excellent stability in harsh environments. According to recent investigations, geopolymer concrete demonstrates low permeability and good long-term behavior, which make it applicable for various purposes. Recent improvements in geopolymer chemistry and geopolymerization processes make this material a promising sustainable cementitious material. Nevertheless, there are some difficulties in application of geopolymer concrete like lack of design guidelines and standardization of mixes as well as the variability in raw materials. This article provides a review of the development of geopolymer technology as an environmentally friendly cementitious material, analyzing geopolymer fresh and hardened properties as well as mechanical and durability performances. The prospects of using geopolymer concrete in infrastructure construction to effectively reduce carbon footprints by recycling industrial waste are discussed.