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The environmental aspects of sustainable development in the construction industry consist of the utilization of secondary raw materials and materials which can be recycled in the design and construction of new structures. The preliminary and inevitable interest in the use of full or partial replacements of by-products as complementary pozzolanic materials was mostly induced by the enforcement of the reduction/elimination of the greenhouse gas emission from the production of Portland cement. With the significant evolution of geopolymer concrete as an alternative for Portland cement in the past decade, it is necessary to explore possible construction applications in which geopolymer concrete can be utilized. Hence, this review paper was carried out to explore various elements such as the precursors used in geopolymers concrete and their corresponding applications. The environmental impacts of various geopolymer concrete are also discussed. This paper also presents an overview of the real applications of geopolymer concrete for the construction of various infrastructures. Recommendations and prospects for geopolymer concrete are also provided. The environmental aspects of sustainable development in the construction industry consist of the utilization of secondary raw materials and materials which can be recycled in the design and construction of new structures. The preliminary and inevitable interest in the use of full or partial replacements of by-products as complementary pozzolanic materials was mostly induced by the enforcement of the reduction/elimination of the greenhouse gas emission from the production of Portland cement. With the significant evolution of geopolymer concrete as an alternative for Portland cement in the past decade, it is necessary to explore possible construction applications in which geopolymer concrete can be utilized. Hence, this review paper was carried out to explore various elements such as the precursors used in geopolymers concrete and their corresponding applications. The environmental impacts of various geopolymer concrete are also discussed. This paper also presents an overview of the real applications of geopolymer concrete for the construction of various infrastructures. Recommendations and prospects for geopolymer concrete are also provided.

The detrimental impact of Portland cement (PC) which is the primary binder in the production of cementitious materials such as concrete has called for a need to use alternative binders to produce concrete. Of such promising sustainable alternative to the conventional PC concrete (PCC) are alkali-activated concrete (AACs) which are produced by using a binder composed of an aluminosilicate precursor and alkali activator. In this study, blast furnace slag (BFS) was used as the primary precursors in the production of AACs. Amorphous raw rice husk ash (RRHA) was used at various dosages to partially replace BFS as the precursor. The corresponding influence of the RRHA content and curing conditions on the performance of AACs were evaluated. The two curing conditions utilized are ambient temperature curing and thermal curing for 24 h at 60 °C followed by ambient temperature curing. Findings from this study showed that the use of RRHA as a 10% replacement of the BFS is optimum as it yielded enhanced mechanical and durability performance. It was also found out that the thermal curing of AACs for 24 h before curing at ambient temperature is beneficial to improving the performance.

In this study, sugarcane bagasse fibres (SBF) were used as a sustainable alternative to reinforce laterite-based geopolymers. As geopolymers can be deemed an eco-friendly construction material, the sustainability of geopolymers can be further improved with the use of SBF which is an agricultural by-product as reinforcement. In addition, the use of natural fibres has been known to improve insulation properties resulting in more energy conservation when such materials reinforced with natural fibres are used for the construction of building elements. Thus, the influence of SBF at various dosages (i.e. 1.5%, 3%, 4.5%, 6% and 7.5%) on the properties of laterite-based geopolymer was evaluated in this study. The outcome of this study indicated that incorporating SBF into the laterite-based geopolymers resulted in a decrease in density and increase in the sonic rate which is beneficial to the acoustic and thermal insulation enhancement. In addition, it was found out that the use of SBF at a dosage of 3% improved the resistance of the geopolymers to wet-dry cycles. However, the presence of SBF in the geopolymers resulted in a decrease in the compressive strength and an increase in the permeability properties with higher content of SBF.

Plastic waste is becoming extremely threatening to the environment due to their high quantities generated which pose serious harm to both the environment and its inhabitants. A major victim of this menace is the marine environment. Plastic wastes generated on land find their way to water bodies where they cause detrimental effects such as flooding and poisoning of the animals in the marine ecosystem. The plastics in the marine environment, which are ingested in fish, are also deleterious to human health if such fish are consumed. Cancer is a major disease that emanates as a consequence. In order to find an effective way to manage these wastes and improve the sustainability of our environment, this study, therefore, explores various approaches to recycling plastic wastes into new products. The critical threat of the presence of plastic wastes in our marine environment is also presented. The limitation of the use of plastic waste for construction applications alongside the prospects is discussed. It is concluded that the use of plastic wastes for construction applications will improve the sustainability of the environment significantly, and also serve as a reliable source of materials for construction purposes. In addition, the use of recycled plastic wastes as a component in cementitious composites has been found to be the most beneficial as it can be used to replace all solid components of the composite. Finally, areas for further studies are also presented.