Mechanical Properties of Metakaolin-Based Geopolymer for Applications in Nuclear Waste Storage
Topic(s) : Material science
Co-authors :
Maryam HOUHOU (FRANCE), Ranaivomanana HARIFIDY , Jean-Daniel PENOT (FRANCE), Leklou NORDINE (FRANCE), De Barros SILVIOAbstract :
High-level radioactive waste (HA) generated in France, primarily from the nuclear power industry, presents a critical need for long-term management. Originating from the treatment of nuclear fuel, this waste possesses high radioactivity and a persistent lifespan. Addressing this challenge, the Cigéo project (Centre industriel de stockage géologique de déchets radioactifs), led by ANDRA (Agence Nationale pour la gestion des Déchets Radioactifs), is developing the establishment of a deep geological disposal facility. This facility consists of horizontal tunnels of 80 m to 150 m long equipped with a carbon steel circular casing designed for storing high-level and long-lived intermediate-level radioactive waste. However, the inevitable corrosion of steel components under anoxic conditions requires a thorough exploration of alternative materials.
As an integral part of the Cigéo project, ANDRA is actively engaged in the exploration and development of new materials to optimize the storage cavity for high-level radioactive waste (HLW). These materials must meet specific requirements equivalent to those currently defined for metallic materials. During the last years, geopolymers have emerged as a subject of growing interest, offering potential as a substitute for steel in the lining cells of HA waste [1]. Beyond meeting mechanical requirements, these materials must also demonstrate (chemical inertness concerning the vitrified waste and the host rock throughout the entire 100 years of reversible operation of the facility)[2] .
Within this context, the primary objective of the ongoing independent study is to formulate a composite material based on metakaolin geopolymer capable of meeting both mechanical and chemical requirements under specific extreme usage conditions, such as high temperatures, low and high relative humidity. The initial phase of the study involves optimizing the binder formulation to enhance mechanical performance under these challenging conditions. Different formulations have been employed, and the resulting materials have undergone comprehensive examination for their mechanical properties, including compressive strength, flexural strength, and elastic modulus. As this research progresses, the insights gained from this investigation will allow us to continue and further investigate other aspects.
As an integral part of the Cigéo project, ANDRA is actively engaged in the exploration and development of new materials to optimize the storage cavity for high-level radioactive waste (HLW). These materials must meet specific requirements equivalent to those currently defined for metallic materials. During the last years, geopolymers have emerged as a subject of growing interest, offering potential as a substitute for steel in the lining cells of HA waste [1]. Beyond meeting mechanical requirements, these materials must also demonstrate (chemical inertness concerning the vitrified waste and the host rock throughout the entire 100 years of reversible operation of the facility)[2] .
Within this context, the primary objective of the ongoing independent study is to formulate a composite material based on metakaolin geopolymer capable of meeting both mechanical and chemical requirements under specific extreme usage conditions, such as high temperatures, low and high relative humidity. The initial phase of the study involves optimizing the binder formulation to enhance mechanical performance under these challenging conditions. Different formulations have been employed, and the resulting materials have undergone comprehensive examination for their mechanical properties, including compressive strength, flexural strength, and elastic modulus. As this research progresses, the insights gained from this investigation will allow us to continue and further investigate other aspects.