Many Nuclear Power Plants around the world are at the moment approaching, or in, their Long Term Operation stage of their operational phase. In addition, several NPPs have recently been carrying out uprate and life extension projects and comprehensive maintenance work including the exchange of components important to safety, in order to extend their lifetime. As a result, ageing management has emerged as one of the main concerns of the nuclear community. The ASCET (Assessment of Nuclear Structures Subject to Concrete Pathologies) program was initiated by the OECD/NEA/CSNI in 2013 and is an international research program targeted at degradation of concrete in nuclear facilities. The project aims to create a basis for general recommendations regarding management of ageing issues in nuclear facilities exposed to concrete pathologies (material degradation mechanisms). The type of investigations necessary to understand and evaluate concrete degradations are determined by each member country based on research needs and damage sensitivity. This report provide an overview of some of the recent research activities carried out by the independent Swedish consultancy company Scanscot Technology, related to various types of assessments of concrete structures (numerical, destructive, non-destructive). Furthermore, the suggested path forward in this research area (concrete material degradation mechanisms), supported by previous research recommendations and operational experiences of the Swedish nuclear industry, is also included. The report is created as a part of the OECD/NEA/CSNI CAPS ASCET programme.
