This study aims to estimate the carbon footprint and relative uncertainties for design components of conventional and geopolymer concrete. All the design components of alkaline-activated geopolymer concrete, such as fly ash, ground granulated blast furnace slag, sodium hydroxide (NaOH), sodium silicate (Na2SiO3), superplasticizer, and others, are assessed to reflect the actual scenarios of the carbon footprint. The conjugate application of the life cycle assessment (LCA) tool SimPro 9.4 and @RISK Monte Carlo simulation justifies the variations in carbon emissions rather than a specific determined value for concrete binders, precursors, and filler materials. A reduction of 43% in carbon emissions has been observed by replacing cement with alkali-activated binders. However, the associative uncertainties of chemical admixtures reveal that even a slight increase may cause significant environmental damage rather than its benefit. Pearson correlations of carbon footprint with three admixtures, namely sodium silicate (r = 0.80), sodium hydroxide (r = 0.52), and superplasticizer (r = 0.19), indicate that the shift from cement to alkaline activation needs additional precaution for excessive use. Therefore, a suitable method of manufacturing chemical activators utilizing renewable energy sources may ensure long-term sustainability.
Wall plaster production induces significant environmental impacts during its entire life as it consumes a high amount of cement and natural resources. Therefore, in sustainable development, industrial wastes are partially replaced to produce cementitious material to reduce environmental impacts. This study aims to identify the optimal environmental benefits from the waste-based cementitious materials that are used to produce wall plaster. Thus, this study involved conducting a comprehensive review of the mechanical and sustainable performance of industrial waste-based cementitious materials focused on wall construction. Then, an experimental test was conducted to ensure the appropriate mix design to enable the required compressive strength. A comparative analysis of mortar showed that it contained 15% (by weight) of fly ash, blast furnace slag, bottom ash, recycled glass, ferronickel slag, expanded polystyrene and wood ash using life-cycle assessment. The results show that mortar containing fly ash has lower environmental impacts in almost all impact categories (i.e., human health, the ecosystem and natural resources). Endpoint damage assessment of mortar mixtures expresses resource extraction cost as the most affected impact criteria. The replacement of globally consumed cement with 15% fly ash can contribute to monetary savings of up to USD 87.74 billion. The assessment clarifies the advantage of incorporating waste products in cement mortar, which allows policymakers to interpret the analysis for decision making. This study also found that the production of industrial wastes for mortar mixes has a significant impact on the environment.