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The pre-eminence of concrete as the constitutional material used for rigid pavement construction has emanated through the millennia thereby amplifying the concern associated with its adverse effect on the environment. In this context, geopolymer concrete not only proposes a sustainable solution but also addresses the problems associated with extensive industrial waste generation and its imprudent disposal. This study aims to highlight the relevance of fly ash (FA) and red mud (RM) as geopolymer synthesizing source materials for pavement quality concrete (PQC). Investigations were designed to study the effect of varying replacement levels of FA (10%, 20%, 30%, and 40%) with RM in conjunction with different concentrations of sodium hydroxide in terms of molarity (10 M, 12 M, 14 M). The specimens subjected to ambient curing and oven curing at 60 °C were tested for compressive strength, flexural strength, and split tensile strength. Results portray that in the case of ambient cured FA-RM specimens, the highest compressive strength and flexural strength that could be achieved were 31.5 MPa and 4.32 MPa, respectively. Thereby, indicating inadequate strength development as per the requirements of PQC, even at a higher concentration of sodium hydroxide. Moreover, replacing FA with RM is mostly not effective at replacement values greater than 20% in both compression and tension. Furthermore, a defined study for assessing durability properties was also conducted by immersing the specimens in a 5% sulfuric acid solution. 11.46% and 7.25% reduction in compressive strength of control mixes was observed for specimens corresponding to 10 M and 14 M respectively, thereby substantiating decreased strength loss at higher molarity. [ABSTRACT FROM AUTHOR]

In the context of ongoing rapid industrialization, the increasing deposition of industrial waste has arisen as a persistent global challenge, necessitating immediate attention and subsequent implementation of sustainable remedies. This study convenes on the efficacy of industrial wastes, namely fly ash and ground granulated blast furnace slag, as geopolymer concrete synthesizers in conjunction with the incorporation of reclaimed asphalt pavement (RAP) aggregates as a replacement for natural coarse aggregates varying over 25% to 100%. Under 7 days of ambient curing, employing 14M NaOH and a 50% RAP replacement, the mix achieved significant strengths of 41.80 MPa in compression and 4.72 MPa in flexure, affirming its suitability for pavement quality concrete (PQC). Through this study, the phenomenon of efflorescence could also be explored, which was particularly significant during the winter seasons. Furthermore, the declining coefficient of determination (R2) with the rise in RAP, observed in the correlation between compressive strength and ultrasonic pulse velocity (USPV), likely signified increased variability in the mixture at higher replacement levels. Assessment of long-term performance in terms of resistance to surface abrasion established the mix as durable, depicting minimal depth of wear (0.081 mm). Furthermore, results of the rapid chloride penetration test (RCPT) demonstrated that the presence of adhered asphalt in RAP aggregates reduces porosity and enhances resistance. Microstructural study was additionally conducted to comprehend the importance of adhered asphalt in impeding crack propagation. ANOVA established a highly significant relationship between the interaction of curing age and RAP fractions with the strength characteristics of the mix. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]