EDF builds scaled-down containment facility for research

Friday, 17 June 2016

EDF has completed building a one-third scale reactor containment facility that will be used to verify construction methods and to study ageing of the materials used in the structure.

The mock-up containment structure under construction (Image: EDF)

Construction of the double-walled containment building - referred to as Vercors (from Verification Réaliste du Confinement des Réacteurs) - started in August 2013 at EDF's research and development laboratory at Renardières in Seine-et-Marne, near Paris.

The structure is 30 meters in height and has a diameter of 16 meters. Some 5000 tonnes of concrete were used in its construction. It features 700 sensors and 2 kilometres of optical fibre positioned in the concrete and on both the rebar and prestressing cables for measuring temperature, deformation and water content of the concrete.

EDF said that during the structure's construction, hourly measurements have been taken from the sensors from just after concreting. It said hundreds of samples of concrete will be prepared and tested to determine their material behaviours and parameters, including strength, drying, shrinkage, creep and leak tightness.

EDF said the scaled-down size of the containment building causes accelerated ageing of the materials used in its construction. Thousands of data readings collected in real time will help researchers better understand how the materials used in the structure evolve over time.

The model will enable its researchers and engineers to better understand and model the phenomena of ageing and leaking through the concrete, to check the robustness of the works and demonstrate the safety of nuclear power plants for extended periods of operation, EDF said.

The containment structure is a major component for protecting nuclear power reactors and preventing the release of radioactive materials into the environment in the event of a serious accident.

Researched and written
by World Nuclear News