Hitachi, Ltd.

Hitachi Plant Engineering Construction Co., Ltd.

Shimizu Construction Co., Ltd.

Akinori Tajiri

Kouichi Ushiroda

Naoto Yoshida

Tatsuo Makita

Masakazu Nagase

Tadashi Matsuura

Hiroshi Hasegawa

Masataka Aoki

Sakae Ebata

Jun Miura

Ryohei Miyahara

Keiya Sato

Kenji Sekiguchi

Tadao Suzuki

Koichi Saito

Hideyasu Furukawa

Yasuyoshi Shimazaki

Shigeru Nanba

Keiji Nakanishi

Masami Hosoda

A cask is lifted from outside of a nuclear reactor building through an opening which is opened at a portion of the nuclear reactor positioned just above a nuclear reactor pressure vessel. By maintaining the cask under a lifted condition a shroud which is an internal structure of the nuclear reactor is transferred and inserted to the cask from the nuclear reactor vessel. After that, an inlet port of the cask is closed, and the cask together with the shroud is lifted outside of the nuclear reactor building through the opening. The internal structure of the nuclear reactor can be speedily carried from the nuclear reactor building with reduced exposure of operators to radioactivity from the radioactive internal structure.

Method of handling a nuclear reactor and an apparatus used in the handling method

A method of handling an internal structure of a nuclear reactor utilizing a receptacle such as a container or a cask. A cask, for example, is lifted from outside of a nuclear reactor building through an opening which is opened at a portion of the nuclear reactor positioned just above a nuclear reactor pressure vessel. While maintaining the cask under a lifted condition, a shroud, which is an internal structure of the nuclear reactor, is transferred and inserted to the cask from the nuclear reactor vessel. Thereafter, an inlet port of the cask is closed so that the cask substantially surrounds the shroud and substantially prevents radiation from the shroud passing therethrough. The cask together with the shroud is lifted outside of the nuclear reactor building through the opening. The internal structure of the nuclear reactor can be speedily carried from the nuclear reactor building with reduced exposure of operators to radioactivity from the radioactive internal structure.

A plate structure block for establishing a surface layer ground is formed integrally with an iron plate on an upper surface of a reinforced concrete member. A lift metal fittings for transporting the block is installed on the block. The surface layer ground establishment block has a large ground bearing pressure and is a portable block. This block is covered on the surface layer ground and establishes the ground for operating a heavy material machinery and/or for maintaining a heavy material member. By operating a mobile heavy crane on the established ground, the working for constructing a plant is carried out. The material for constructing the ground is reused, the shape of the ground site is easily changed, and the dismantling and removal of the ground is simplified.

Surface layer ground establishment block, surface layer ground using the

In a method of construction of a reinforced concrete diaphragm floor of a nuclear reactor reinforced concrete containment vessel, a bottom surface of the diaphragm floor is provided in the form of an iron plate. The iron plate, an iron bar beam portion for supporting the load provided by concrete during a concrete pouring time, and a reinforcing bar member to be buried in the concrete of the diaphragm floor are assembled outside of a building in which the nuclear reactor is to be embodied. The above members are carried using lifting machinery and are set in a permanent receiving member which is provided on both a main body of the nuclear reactor pressure vessel and a steel member serving as a concrete mold frame of an outer wall of the nuclear reactor reinforced concrete vessel. A concrete pouring is carried out in stages so as to form successive layers of concrete during plural pouring times. After a first concrete layer has completed and the strength of the concrete layer has been established after hardening, the second concrete layer is poured on the first layer, which aids in supporting the weight of the poured concrete.

Construction method of nuclear reactor reinforced concrete containment

A method of constructing a top slab to provide a containment roof over a nuclear-power generating building, in particular, a method for utilizing overhead spaces bounded by a wall of the containment building and a shielding wall of the pressure vessel building, wherein the sequential steps involve; erecting a plurality of paired support columns on tops of the wall and of the shielding wall; building upper structural components across said paired support columns; installing a slab liner equipped with slab anchors beneath said lower structural components by suitable joining means; constucting a reinforcing network above said lower structural components; encasing said lower structural components and said reinforcing network; and pouring concrete over the slab liner to a suitable depth.

Method of construction of top slab for a nuclear containment building

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Hitachi, Japan

Akinori Tajiri