Structural mechanics and nuclear steam supply system maintenance Original Research Article

Electricité de France (EDF) is now operating 54 pressurized water reactors. This represents already more than 500 reactor-years of experience which allowed EDF to develop its own maintenance policy and strategies. These strategies are backed by analysis which frequently relies on structural mechanics studies to such a point that important maintenance decisions may depend on the capacity to solve problems in that field. Development of monitoring and on-line surveillance, in-service inspection programmes, integrity assessment of degradations, and definition of preventive measures require frequently the use of structural mechanics, from simple stress analysis to state-of-the-art fracture mechanics. Various examples may be given, among which the case of steam generator tubing is typical. All these works require important resources, in the field of computation capacity as well as testing facility. Good results in terms of availability and safety confirm the usefulness of structural mechanics in maintenance activities.