ENSURE: Efficient Nuclear Shielding with Ultra-durable low-caRbon concretE

There is a growing global interest in utilizing radioactive sources, exploring their potential for energy generation and diverse applications in medical and military sectors. Although there were previous intentions to phase out nuclear power, on June 20, 2023, Sweden's parliament changed its energy objective from "100% renewable" to "100% fossil-free"electricity. The revised approach aims to address the projected doubling of electricity demand to about 300 TwH by 2040 and to achieve net-zero emissions by 2045, allowing for the potential construction of new nuclear plants in the future. Consequently, implementing protective measures becomes crucial to prevent potential health and environmental risks associated with a wide range of radiation sources.

Concrete is a cost-effective material with the flexibility to be shaped into various configurations. Its ability to efficiently attenuate neutrons and gamma rays is due to its inherent moisture content and comparatively dense composition. The synergy of these characteristics has resulted in concrete being widely utilized as a substance for shielding against radiation. However, it still has notable limitations, for instance, considering the durability of the material or the effect of the high-temperature exposure on the possible radiation shielding deterioration of the material. The last concrete reactor was constructed in Sweden in the 1980s, and vast progress has been made in the concrete technology area since then, with a widespread application of ecological binders and nanotechnology to enhance the environmental and mechanical performance of cementitious materials. Nevertheless, there is a large knowledge gap regarding the potential of new concrete compositions in radiation shielding.

The public perception of nuclear energy and its safety features can influence the demand for enhanced radiation shielding materials. If there is heightened concern about nuclear safety, there may be a push for improved shielding solutions to alleviate public worries and enhance confidence in nuclear facilities. The development of new shielding materials with increased durability and high efficiency of radiation protection could help raise public awareness of the safety of nuclear energy solutions.

The project aims to better understand how the interaction between harsh environments, exposure to high temperatures, and the presence of gamma and neutron radiation affects the longevity and mechanical performance of low-carbon concrete. The focus of the research is on two areas, i.e., the interfacial transition zone between coarse aggregate/binder matrix and high-temperature performance of the material. In addition, the potential of achieving self-healing properties of the concrete will be studied. Low cost, local availability and environmental impact of the used ingredients will be considered.