Comparison of Carbon–Neutral Geopolymer and OPC Concrete for Nuclear Shielding Applications

AbstraktAbstract

The development of carbon–neutral geopolymer-based materials is highly desirable, given current trends in the construction industry. Overall, geopolymer is considered a favourable, sustainable substitute for cement-based concretes. This approach could also be applied to heavy radiation shielding concrete used in nuclear power plants (NPPs), where the unique properties of geopolymer-based materials may exceed those of traditional concrete. This study aimed to create a substitute with equivalent shielding capabilities while maintaining the same chemical composition of bound water, boron, and iron using qualified raw materials. A comparative analysis was conducted between traditional heavy-shielding concrete and a novel geopolymer-based material using advanced characterisation techniques, including scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS), powder X-ray diffraction (PXRD), and X-ray computed tomography (CT). This allowed for deeper investigation of macro- and microstructural characteristics, phase identification, three-dimensional visualisation, and quantification of pore structures and material homogeneity. Shielding capabilities were assessed using a high-purity germanium (HPGe) detector and gamma radiation sources in a controlled environment. Accordingly, this paper surveys a promising path towards sustainable radiation shielding solutions for nuclear facilities and other high-radiation environments.

The development of carbon–neutral geopolymer-based materials is highly desirable, given current trends in the construction industry. Overall, geopolymer is considered a favourable, sustainable substitute for cement-based concretes. This approach could also be applied to heavy radiation shielding concrete used in nuclear power plants (NPPs), where the unique properties of geopolymer-based materials may exceed those of traditional concrete. This study aimed to create a substitute with equivalent shielding capabilities while maintaining the same chemical composition of bound water, boron, and iron using qualified raw materials. A comparative analysis was conducted between traditional heavy-shielding concrete and a novel geopolymer-based material using advanced characterisation techniques, including scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS), powder X-ray diffraction (PXRD), and X-ray computed tomography (CT). This allowed for deeper investigation of macro- and microstructural characteristics, phase identification, three-dimensional visualisation, and quantification of pore structures and material homogeneity. Shielding capabilities were assessed using a high-purity germanium (HPGe) detector and gamma radiation sources in a controlled environment. Accordingly, this paper surveys a promising path towards sustainable radiation shielding solutions for nuclear facilities and other high-radiation environments.