Radiation effects in concrete for nuclear power plants – Part I: Quantification of radiation exposure and radiation effects

• Published in: Nuclear engineering and design Vol. 282; pp. 126 - 143
• Main Authors: Field, K.G., Remec, I., Pape, Y. Le
• Format: Journal Article
• Language: English
• Published: United States Elsevier B.V 01.02.2015
• Subjects: amoprhization; Biological; Concrete; Concrete structures; Concretes; Fluence; Light water reactors; neutron; Nuclear power generation; Nuclear power plants; Shields; swelling
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2014.10.003

•Neutron and gamma rays fields in concrete biological shield are calculated.•An extensive database on irradiated concrete properties has been collected.•Concrete mechanical properties decrease beyond 1.0×1019n/cm2 fluence.•Loss of properties appears correlated with radiation induced-aggregate swelling.•Commercial reactor bio-shield may experience long-term irradiation damage. A large fraction of light water reactor (LWR) construction utilizes concrete, including safety-related structures such as the biological shielding and containment building. Concrete is an inherently complex material, with the properties of concrete structures changing over their lifetime due to the intrinsic nature of concrete and influences from local environment. As concrete structures within LWRs age, the total neutron fluence exposure of the components, in particular the biological shield, can increase to levels where deleterious effects are introduced as a result of neutron irradiation. This work summarizes the current state of the art on irradiated concrete, including a review of the current literature and estimates the total neutron fluence expected in biological shields in typical LWR configurations. It was found a first-order mechanism for loss of mechanical properties of irradiated concrete is due to radiation-induced swelling of aggregates, which leads to volumetric expansion of the concrete. This phenomena is estimated to occur near the end of life of biological shield components in LWRs based on calculations of estimated peak neutron fluence in the shield after 80 years of operation.