Reactor anti-burst container esp. of prestressed concrete - has bottom slab which can be lowered for inspection of vessel base

摘要

A nuclear reactor plant with anti-burst protection comprises a surrounding anti-burst container, which rests on a foundation and, in the hot operating conditions of the reactor pressure vessel, restrains the vessel axially and surrounds it with at least a narrow gap. The container comprises a top slab, a generally cylindrical wall and a bottom slab. The cylindrical wall is supported from the foundation quite independently of the bottom slab; The bottom slab is detachably connected to the cylindrical wall and is normally at a specific distance above the foundation, so that the bottom slab can be lowered to provide a clearance below the cylindrical wall to give access for inspection of the base of the vessel. Pref. the entire container is of prestressed concrete and the axial prestressing tendons suspend the bottom slab from the cylindrical wall and can be released to lower the bottom slab. Access for inspection of the bottom of the vessel is possible. Access is conventionally available to the sides and top fo the vessel by stripping off insulation. The system can be used either for the case where the cylindrical wall does not support the pressure vessel in the operating case or where it does provide partial restraint to the vessel.