JPS6031280B2 - How to line the pool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for lining construction of nuclear power brand buildings, spent fuel storage pools, etc., where leakage of gas or liquid containing radioactive materials is strictly regulated.

When lining nuclear power facilities, it is absolutely necessary to prevent the leakage of radioactive materials that are harmful to the human body, but because these structures are large, the joints of the lining plates must be welded on site, and the backing of the weld line must be welded. How to attach the metal embedded metal fittings becomes an important issue for welding workability and welding reliability of the lining plate. In addition, in the event that there is a leak from a weld, it is necessary to be able to detect it from a distance and take action. As shown in Fig. 1, the conventional pool lining method involves embedding anchors 2 (or 2') in a reinforced concrete frame 1, attaching angle irons 3 to these in a grid pattern, and filling the mortar 4 up to the surface of the anchors to line the inner surface of the pool. It is common to finish the stainless steel lining plate 5 using the angle iron 3 as a backing metal.

However, with this method, it is difficult to accurately install the angle iron 3, and it is easy to modify the unevenness of the surface of the mortar 4 or to make a part where the grooves of the lining plate are poorly aligned. There are many drawbacks. Further, since the leakage detection groove 6 is formed of mortar, it cannot be detected unless there is a large amount of leakage, and it is not easy to search for the leakage location. In the present invention, an embedded fitting with a leak detection groove (hereinafter referred to as an embedded fitting) as shown in Fig. 2 and a steel formwork as shown in Fig. 3 are manufactured in a factory, and these are assembled on-site. This is a construction method in which the pool body is constructed by using a predetermined temporary frame and pouring concrete around it. After the concrete has cured, the steel formwork is removed to complete the pool body with embedded metal fittings embedded. . This method will be explained below based on FIGS. 2 to 5.

FIG. 2 shows a plan view and a partial cross-sectional view of the embedded hardware, in which a hair pad 8 and a backing plate 9 are welded to the surface of a steel frame plate 7.
A leakage detection groove 10 is formed by providing an appropriate gap between the backing metal 8 and the backing plate 9. An anchor 11 and a detection tube supporter 12 are attached to the back side of the frame plate 7. The embedded hardware shall be divided into pieces of transportable size and assembled into a predetermined shape after being delivered to the site.The dimensions shown in Figure 2 are an example. Figure 3 shows a plan view and a cross-sectional view of the steel formwork, which is made up of a steel formwork 13 and a cover plate 14, and is provided with bolt holes for mounting embedded hardware, bolt holes for formwork assembly, separator mounting holes, etc. .

Figure 4 shows a partial cross section of the connection between the embedded metal fittings and the steel formwork during on-site assembly work. After the detection pipe 17 and various embedded pipes are arranged between the reinforcing bars 21, the cover plate 14 is temporarily attached with bolts 18 and the separator 19 is arranged to form a temporary inner frame of the pool frame. After pouring the pool fat concrete 22 and curing it, remove the temporary bolts 15, 16, 18, and remove the formwork 13 and cover plate 14 to create a pool with dimensionally accurate leak detection grooved embedded fittings. The key body is completed. FIG. 5 shows a cross section of the welded joint of the metal lining plate, and the stainless steel lining plate 20 is welded onto the backing metal 8 of the embedded metal to complete the pool lining work. Welding of the lining plate 20 is conventionally performed by butt welding on the backing metal 8 of the embedded metal fittings, but since the beveling of the lining plate and the embedded metal fittings are precisely manufactured in the factory, on-site welding is required. It becomes easy to align the joints and complete welding can be performed.

Leak detection steel is provided on both sides of the weld line, and if a leak should occur, it will be rapidly detected by the detection piping 17 arranged in each block, and the location of the leak can be easily searched. In addition, the metal fittings are embedded at the same time as the concrete is poured, and the steel formwork can be used many times, which is effective in shortening the construction period and making the nuclear facility more economical. As described above, the present invention is applicable to nuclear power-related structures where leakage of radioactive materials is strictly regulated and requires stainless steel lining, such as bits around nuclear reactors, spent nuclear fuel pools, nuclear fuel reprocessing plant buildings,
Effective for lining construction of radiation irradiation pools, etc.

[Brief explanation of the drawing]

Figure 1 is an example of the conventional construction method, Figure 2 is a leak detection grooved fitting, Figure 3 is a steel formwork, Figure 4 is an assembly method, and Figure 5 is an explanatory diagram showing a lining plate welding method. be. Explanations of the symbols shown in the figure are as follows. 1...Reinforced concrete frame, 2...Anchor, 3...
... angle iron, 4 ... mortar, 5 ...
...Lining plate, 6...Leak detection groove, 7...
...Steel frame plate, 8...Backing metal, 9...
Contact plate, 10... Leak detection groove, 11...
Anchor, 12...Detection tube handle, 13...
...Formwork, 14...Lid plate, 15...Bolt, 16...Bolt, 17...Detection tube,
18... Bolt, 19...Separator, 20
...Lining plate, 21...Reinforcement bar, 22...
···concrete. Figure 5 Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. In the construction of a pool for a nuclear facility where concrete walls are lined with metal plates, a steel plate embedded metal fitting with a welding backing metal and a leakage detection groove embedded in the concrete base at the joint of the metal plate is made of shaped steel. This is a method in which the inner wall surface is formed by combining multiple forms with attached steel plate cover plates, and then concrete is poured to construct a concrete body.
A pool lining method characterized in that by using a removable steel plate cover plate, it is easy to assemble the model and attach a leak detection tube.