Sustainable concrete: Building a greener future

Abstract In an effort to reduce waste and engage in more sustainable construction, this research focuses on the development of a cost-competitive, environmentally-friendly geopolymer concrete mixture that offers structural benefits relative to ordinary Portland cement (OPC), uses fly ash, a toxic waste byproduct as a raw material, and reduces the amount of CO2 emitted during production of the concrete. The production of OPC, the current standard in concrete, relies on a high amount of energy, and as a result accounts for 7% of CO2 emissions worldwide. Production of OPC is expected to increase 4-fold over the next 30 years, posing significant environmental risk. While numerous studies have examined the use of geopolymer concrete as a more sustainable construction material, concerns about the cost and environmental impact are obstacles against widespread production and market adoption. The new mix designs proposed herein result in up to a 50% decrease in the cost of geopolymer concrete, making this sustainable alternative a viable option relative to traditional concrete. In addition, the production of the proposed mixtures requires less than 50% of the fuel usage (thermal energy) required for OPC, decreasing CO2 emissions. The proposed mixtures not only reduce environmental impact, but they also offer improved performance, which may appeal to many concrete manufacturers. While the proposed alternative to Portland cement is suitable for most applications, it is posited that those firms interested in pursuing sustainable construction may be most inclined to adopt the proposed mixture in order to meet their sustainability goals.