Mechanical and leakrate predictions for nuclear power plant containments in accidental conditions

In 1996, EDF decided to build a containment model at the scale 1:3, the Maq uette exchange vapeur/air (MAEVA) mock-up, in order to check and study the behavior of a prestressed concrete containment vessel without liner in term s of mechanical strength and leaktightness, for loadings corresponding to i ts design and beyond design conditions. In parallel to the construction and testing of the mock-up, predictive calculations of the mechanical and leak tightness behaviour of the mock-up were performed in the framework of a cos t shared R&D action supported by the European Union, the Containment Evalua tion under Severe Accidents (CESA) project. The strategy of EDF concerning the R&D performed on leaktightness of concrete and concrete structures is f irst explained and the goal of two interesting programs is shortly presente d and discussed in the first part of the paper. Then, the emphasis is made on the predictive calculations performed on the MAEVA mock-up by means of f inite elements (FE) calculations, A summary of the main achievements is the n given and the interest of FE calculations is discussed for describing bot h the mechanical and leaktightness behaviour of a concrete structure as a f unction of crack development. (C) 2001 Elsevier Science B.V. All rights res erved.