JPH01242995A - Shell wall of nuclear reactor building - Google Patents

Abstract

PURPOSE:To facilitate reinforcement construction such as the working and assembly of reinforcing bars, formwork, and concrete construction and to shorten the construction period and to reduce the cost by forming the upper part of the shell wall corresponding to the spherical shell part at the upper part of a reactor container in a cylindrical shape. CONSTITUTION:A nuclear reactor pressure vessel 2 is installed in the center part of the nuclear reactor building 1 and the outside of the container 3 is covered with the shell wall 4 made of reinforced concrete. This shell wall 4 consists of a small-diameter cylinder part 4a and a large-diameter cylinder part 4b in a two-stage cylinder shape, and this step part is formed at the position corresponding to the upper spherical shell part of the container. The thickness of the shell wall 4 is made uniform. In this constitution, when the shell wall 4 is structured, none of longitudinal bars 6, 6... is curved because of there is no three-dimensional curved surface in the reinforcement construction, and lateral bars 7, 7... are only curved with the same curvature as the cylinder part 4b. Further, the longitudinal bars 6, 6... are equal in pitch to the cylinder part 4b at the part where the spherical shell part 5 is formed and not changed in shape at the upper parts.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a nonyl wall Z made of reinforced concrete that houses a reactor containment vessel in a nuclear reactor building.

``Prior art'' Conventionally, the shell wall of a nuclear reactor containment vessel (hereinafter referred to as the containment vessel), such as the MARK I type, whose upper part is formed into a spherical shell shape has been used to form the shell wall of the containment vessel. , f is known to have a spherical shell shape along the containment vessel.

FIG. 2(a) is a partially sectional front view showing a conventional latch, and FIG. 2(b) is an enlarged sectional view of a portion surrounded by a broken line in FIG. 2(a). In the figure, reference numeral 4 denotes a shell wall made of reinforced concrete constructed to accommodate the containment vessel 3, and the shell wall 4 has a small diameter cylindrical portion 4a along the outer contour of the containment vessel 3. It is composed of a spherical shell part 5 and a large diameter cylindrical part 4b.

``Problems to be solved by inventions'' In recent years, as nuclear power generation has become more widespread, electric power companies have taken a deep interest in reducing costs and shortening construction times as a means of maintaining their advantage. Incidentally, shell wall construction is one of the critical power path construction works in nuclear reactor building construction, and by shortening the construction period for this shell wall construction, it is possible to significantly shorten the entire building construction period.

By the way, currently, the nonyl wall covering the prefectural reactor containment vessel, which has a spherical upper part, has a spherical shell part that follows the spherical shell shape of the containment vessel. When constructing the three-dimensional curved surface to be formed using reinforced concrete, the reinforcement work requires a great deal of effort because the reinforcement arrangement is extremely complicated. In addition, concrete work requires a large amount of concrete, and the common method is to support the top of the steel plate formwork from the containment vessel with temporary bolts; Due to accuracy and strength considerations, the height of concrete placed once is limited to, for example, about 1.5 m to 2 m. As a result of the above, the amount of time required to construct the spherical shell portion is approximately twice that of the construction of the large diameter cylindrical portion below it.

The present invention was made in view of the above circumstances, and aims to realize a shell wall in which reinforcing steel work such as processing and assembly of reinforcing bars, formwork work, and concrete work are easy and hassle-free, that is, the construction period is short. .

"Means for Solving the Problems" In order to solve the above problems, the present invention provides a nuclear reactor building equipped with a shell wall made of reinforced concrete that houses a reactor containment vessel whose upper part is formed into a spherical shell shape. The upper part of the shell wall corresponding to the spherical shell part at the upper part of the containment vessel was made into a cylindrical shape.

``Function'' Since the three-dimensional curved surface of the upper part of the shell wall becomes a two-dimensional curved surface, reinforcing steel work, formwork work, and concrete work can be easily performed.

"Example" Figure 1 shows an example of the present invention.
a) is a partially sectional front view, and FIG. 1(b) is a partially sectional front view of the same.
FIG. 3 is an enlarged cross-sectional view of the region surrounded by the broken line in a). In the figure, reference numeral 1 is a reactor building that houses the reactor body.

A reactor pressure vessel 2 is installed in the center of the nuclear reactor shelter 1. The reactor pressure vessel 2, together with a part of the main steam system, the reactor coolant recirculation system (both not shown), and the like, are capable of being discharged from the reactor even if an accident occurs in these systems. In order to prevent certain radioactive substances from dispersing to the outside, they are stored inside a steel containment vessel 3. Furthermore, a nonyl wall 4 made of reinforced concrete covers the outside of the containment vessel 3. The shell wall 4 has a small diameter cylindrical portion 4a.
It is formed into a two-step cylindrical shape with a large diameter cylindrical portion 4b, and the stepped portion is formed at a position corresponding to the upper spherical shell portion of the containment vessel 3. Further, the shell wall 4 has a uniform thickness (1.9 m in this embodiment).

Incidentally, the top slab of the shell wall 4, that is, the flat portion formed at the stepped portion of the small-diameter cylindrical portion 4a and the large-diameter cylindrical portion 4b, is a portion of the fuel storage boule 9 and the reactor equipment temporary storage pool 10. It consists of

Construction of the shell wall configured as described above is difficult because there is no three-dimensional curved surface in reinforcing steel construction, so
・・Cutting curve machining is no longer required. Also, horizontal muscle 7.7・
... also had to be processed by changing its curvature for each step in order to form a spherical shell, but this was not necessary and the bending process could be performed using a curve with the same ratio as the lower large-diameter cylindrical portion 4b. This greatly improves processing productivity. In addition, the pitch of the vertical lines 6,6, etc. is conventionally the same as that of the large diameter cylindrical part 4b in the part where the spherical shell part 5 is formed, and does not become narrower as it goes upward. The workability of reinforcing reinforcement layout for the fuel storage pool 9, the temporary reactor equipment storage pool IO, etc. is improved.

Therefore, by making the moeki spherical shell part 5 into a cylindrical shape, the reinforcing steel work required in constructing the shell wall 4 can be halved, resulting in a significant reduction in the construction period. Furthermore, in concrete construction, the volume occupied by the concrete structure 8 surrounding the shell shoulder corresponding to the spherical shell 5 of the containment vessel 3 is reduced, so the absolute amount of concrete used is significantly reduced. do.

In addition, the cylindrical shape reduces the surface pressure applied to the formwork during concrete pouring, allowing the concrete to be poured at a greater height than conventional shapes, thereby reducing the number of pours. Each time the number of pours is reduced by one, steps such as pre-pouring inspection and curing are eliminated, resulting in a reduction in construction time of 3 to 4 days for each pour. Therefore, in combination with the above-mentioned reinforcing steel work, it is possible to shorten the construction period by approximately - months or more.

"Effects of the Invention" As explained above, the present invention provides a reactor building equipped with a shell wall made of reinforced concrete for accommodating a reactor containment vessel whose upper part is formed into a spherical shell. Since the upper part of the shell wall corresponding to the spherical shell part of is made into a cylindrical shape, reinforcing steel work such as processing and assembly of reinforcing bars and formwork work,
Concrete work is extremely simple, resulting in significant shortening of construction period and cost reduction.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) are a partly cross-sectional overall front view and an enlarged view of the partly cross-sectional view showing an embodiment of the present invention. FIGS. 2(a) and 2(b) are a partially cross-sectional overall front view and an enlarged view of the partially cross-sectional view of a conventional lantern. I... Reactor building, 2... Reactor pressure vessel, 3... Reactor containment vessel, 4...
... Nonyl wall, 5 ... Spherical shell part, 6
... Vertical muscle, 7... Horizontal muscle. Applicant Toshiba Shimizu Corporation Figure 1 (014゜(b) b

Claims (1)

[Claims] In a reactor building equipped with a shell wall made of reinforced concrete that houses a reactor containment vessel whose upper part is formed into a spherical shell shape, the upper part of the shell wall corresponding to the spherical shell part of the upper part of the containment vessel is formed into a cylindrical shape. A shell wall of a nuclear reactor building featuring.