The evaluation of the condition of some types of concrete structures is possible by following guidelines set out in procedures and manuals, such as the "Handbook for Bridge Inspection" published by the Swedish Road Directorate. It would be desirable to have similar guidelines for other categories of important structures, particularly in cases where safety aspects are dominant. A nuclear power plant (NPP) consists of a number of functionally different structural components in a variety of environments and effective inspection is only possible if we know what we are looking for and have the capability to apply reliable and relevant testing techniques.
This report briefly discusses actual and potential deterioration processes and their causes based upon several years of investigative work on concrete structures in Scandinavia, including NPP and provides some input for development of practical inspection procedures. Some common deterioration processes are highlighted to bring attention to the need for inspection. A more detailed study of chloride attack and reinforcement corrosion is presented, and finally a summary is given of state-of-the-art technologies for in-situ testing.