Concrete Technology program for nuclear power plants

The nuclear power plants in Sweden and Finland were built during the seventies/eighties and it is planned to extend their service life and increase their production capacity. The challenges are now to assess the condition of the concrete structures; to verify whether or not the structures can withstand the prescribed loads and functions; and verify if the structures can be upgraded in order to fulfil the requirements regarding load bearing and functional capacity. A research program was launched whose priority is condition assessment of the reactor containment. The research includes condition of the pre-stressing reinforcement, reinforcement bars, lining, leakage etc. The conditions are assessed both by destructive and non-destructive test methods. The addressed properties are physical, mechanical, electro-chemical and geometrical. The paper presents the organisation of the program, the co-operating partners, the research program, and the content of the on-going and planned research projects