Analysis of a cylindrical prestressed concrete pressure vessel with a large central penetration in the slab

Abstract

This paper describes briefly the design analysis carried out for a cylindrical prestressed concrete pressure vessel of a Boiling Water Reactor of a 1000 MWe Nuclear Power Plant, on behalf of the “Société d'Etudes et d'Equipements d'Entreprises” (SEEE), Paris. The main aim of this study was to determine the global influence of a large central penetration in the slab, on the stress and deformation pattern of the vessel. The method adopted is based on the finite difference analysis using the Dynamic Relaxation process with the aid of an IBM 7040 computer. The penetration was taken into account by assuming it to be filled with a material of negligible modulus of elasticity. Results of three basic loadings; internal working pressure of 84 kg/cm 2, temperature gradient of 30°C and prestressing are given. The importance of modifications, due to the presence of a large central penetration, in the overall stress and deformation pattern in the slab is revealed. It was found that such a study, besides the local examination of stress distribution around the penetrations, is necessary.