JPH0476877B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a lined storage pool that is widely used in nuclear power plants, waste treatment facilities, general chemical plants, etc., and is particularly easy to construct. The present invention also relates to a storage pool provided with a mechanism for detecting liquid leaking from joints of lining panels.

(Prior Art and its Problems) In nuclear power related facilities and general chemical plants, storage pools are widely used in which the inner surface of a tank made of concrete or ordinary steel is lined with a metal such as stainless steel.

For example, nuclear power plant facilities have pools for storing radioactive waste, where the waste is stored for long periods of time in order to attenuate its radioactivity. They are also used in chemical plant facilities to temporarily store toxic products and waste.

Because the stored materials are highly radioactive and highly toxic, storage pools are subject to particularly strict design conditions in terms of not only corrosion resistance but also leakage, in the unlikely event that a leakage is detected. in case of,
A means to detect this early and reliably is essential. Therefore, in many conventional storage pools, a leakage detection mechanism is provided near the bottom plate on the outside of the storage pool. However, conventional detection mechanisms either detect leakage water that penetrates the narrow gap between the lining panel and the concrete surface and reach one or several leakage detection tanks installed near the bottom plate, or detect leakage water that penetrates the narrow gap between the lining panel and the concrete surface and reaches one or several leakage detection tanks located near the bottom plate. A sensor detects the leakage water that reaches the annular leakage water tank installed at the bottom of the periphery. Therefore, depending on the sensitivity of the sensor, there is generally a considerable time delay after a leakage accident occurs until it is actually detected by the sensor, making early detection and early repair difficult. In addition, the conventional detection mechanism is configured to collect water leaking from the entire surface of the lining panel into one or several liquid receiving tanks.
Because each part was not independent, it was often difficult to pinpoint the location of the leak. In other words, in order to find one leakage point, it is necessary to trace over a wide area, including all the weld lines of the lining panel, which has the disadvantage that detecting the leakage point requires a great deal of time and effort.

Furthermore, if we take a conventional lined storage pool of this type in which the outer wall is made of concrete, generally a lining material 51 such as stainless steel is attached to the inner peripheral surface of a concrete frame 50 that is the pool body, as shown in FIG. It has a built-in structure.
That is, a frame 52 assembled in a lattice shape is buried in the concrete frame 50 so that its front surface is exposed inside the tank. This frame 52 serves as a backing when the peripheral edges of adjacent lining materials 51 are welded together, and also serves to fix the lining materials 51 to the concrete frame 50. The design is designed so that the adjacent weld lines 53 do not intersect in a criss-cross pattern, so that the weld lines are staggered and installed in a so-called brick stack arrangement.

According to this conventional structure, after constructing the concrete frame 50 in advance, the lining material 51 is applied to the inner surface of the concrete frame 50 in a post-pasting manner, making it extremely difficult to inspect the quality of the joint welded portion of the lining material 51. That is, the joining work can only be done by welding one side from the inside of the tank, and the only way to confirm the quality of the welding is to rely on external visual inspection, vacuum testing, and penetrant testing.

These methods detect external defects such as undercuts, poor penetration, and cracks that appear on the surface of the weld line 53, but it is difficult to inspect blowholes and other internal defects.

Furthermore, the back side of the bonded lining material 51 is already occupied by the thick concrete frame 50, leaving only a narrow space. Note that even if the concrete frame 50 has not yet been cast, there are already many densely arranged reinforcing bars, etc., and workability on the back side of the lining material 51 is extremely poor. In such a situation, it is extremely difficult to further incorporate leakage detection grooves and detection piping (not shown) on the back side of the lining material 51 after assembly. As a countermeasure, a window frame-shaped opening 54 is provided in the center of the lining material 51, through which a worker can insert his/her hand and temporarily secure the lining material 51 to the frame with bolts and nuts, or assemble the leakage detection equipment. It is also a conventional practice to use the aperture 54 and then close the aperture 54. However, according to this structure, in addition to the original welding line length of the lining material 51, the welding line of the plate material for closing the opening 54 is added, which requires a huge amount of welding man-hours and inspection costs. There were numerous shortcomings.

(Means for Solving the Problems) The present invention was devised to solve the above-mentioned problems. The reinforcing ribs assembled on the storage pool are designed to form leak detection grooves together with the sides of the frame to which the panels are attached.In particular, the construction of the side walls and the assembly of the leak detection grooves can all be done from inside the storage pool, and the leak detection points can be easily This provides a sidewall structure that allows quick identification of the sidewall.

The gist of this invention is to construct a panel mounting frame 1 by joining shaped steel materials such as angle steel and channel steel in a lattice shape on the base bottom plate of a storage pool, and to construct a panel mounting frame 1 with reinforcing ribs that fit into the inner edges of each lattice. The lining panels 2 of a predetermined shape assembled with 3 are laid on the panel mounting frame 1, and the peripheral edges of each lining panel 2 are butt welded using the panel mounting frame 1 as a backing material to integrate the side walls of the storage pool. On the other hand, by forming small holes 6 that communicate vertically at both ends of the horizontal member 4 of the panel mounting frame 1, the side surface of the vertical member 5 of the panel mounting frame 1 and each lining panel 2 are connected. A small gap formed between the side surface of the reinforcing rib 3 and the side surface of the reinforcing rib 3 is provided so as to communicate in the vertical direction, and this gap is used as a leakage detection groove 7, and the bottom plate 8 located at the lowest end of this groove is
This is where the leak detection piping 9 is led out from.

(Example and operation) Hereinafter, an example of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a partially cutaway perspective view of a side wall corner of a storage pool according to the present invention. Note that the illustration is shown with a part of the panel removed.

1 is a bottom plate 8 laid on a concrete foundation 10
This is a panel mounting frame built on top of the panel, and is formed by assembling shaped steel materials such as angle iron and channel steel alternately in the vertical and horizontal directions in a lattice shape.

That is, the frame 1 is constructed by vertical members 5 corresponding to the depth of the storage pool erected at predetermined intervals, and horizontal members 4 bridging and reinforcing the spaces in multiple stages.

Note that the positional relationship and construction order between the panel mounting frame 1 and the reinforced concrete wall 12 will be explained here. The panel mounting frame 1 may be assembled before the reinforced concrete wall 12 is constructed, but usually the panel mounting frame 1 is assembled after the primary concrete is poured to form a concrete wall with a thickness slightly less than the predetermined dimensions. Assemble 1, attach a panel to the front of it, and then,
A concrete wall 12 of a predetermined thickness is formed by pouring secondary concrete into the gap between the panel and the already constructed concrete wall.

That is, the panel mounting frame 1 is ultimately buried within the concrete wall 12 with only its end face 11 exposed inside the pool, but at the stage of laying the lining panels 2 and joining them together, as described above, This is the time when the reinforcing bars of the concrete wall 12 are placed or the first concrete is placed, and the panel mounting frame 1
There is only enough space left behind for the worker to insert his hand. Therefore, workability on the back side of the panel is generally extremely poor.

12 is a lining panel attached to the end surface 11 of the frame.

A reinforcing rib 3 formed to fit into the inner edge of each grid of the frame is assembled on the back side of the panel. In addition, if necessary, reinforcing material is also incorporated in the intermediate portion as shown in the figure to prevent deformation. As the lining panel 2, several types of standard panels having predetermined dimensions are prepared depending on the shape of the pool.

In the drawing, flat panel 2 is attached to the flat part.
a and the corner panel 2b attached to the corner of the pool
exemplify.

When constructing the side walls, first the lining panels 2 integrated with the reinforcing ribs 3 are fitted into each lattice frame of the mounting frame 1 one after another, and then the peripheral edges of the lining panels 2 are joined by butt welding. . At this time, the end surface 11 of the panel mounting frame 1 is used as a backing metal, and welding is performed by complete penetration, so that the lining panels 2 are welded to the panel mounting frame 1 at the same time as they are joined to each other. Next, one embodiment of the leakage detection mechanism will be described with reference to the drawing in FIG.

Figure 2 shows a partially broken bottom corner of the storage pool.
FIG. 2 is an enlarged perspective view.

In the figure, 7 is a leak detection groove formed between the side surface of the vertical member 5 of the frame and the reinforcing rib 3 joined to the panel 2. The detection grooves 7 are formed on both the left and right sides of the vertical member 5 of the frame and on the upper and lower sides of the horizontal member 4. However, since the leakage detection grooves 7 provided along the vertical member 5 are all connected in the vertical direction, each horizontal Small holes 6 are bored at both ends of the member 4.

That is, all of the leak detection grooves between adjacent vertical members 5 communicate in the vertical direction in both the vertical portion and the horizontal portion.

Note that although the gap between the leakage detection grooves 7 is drawn wide in the drawing for the sake of explanation, it is actually about 1 mm. 9 is a leak detection pipe led out from the bottom of the bottom plate 8 located at the lowest end of the vertical leak detection groove 7, and each pipe is individually connected to a leak water detection sensor, an alarm, etc. (not shown). connected to equipment. In the unlikely event that water leaks from the weld line 13 of the lining panel 2 due to corrosion, cracking, etc., the leaked water will go around the panel mounting frame 1 as shown by the arrow and flow downward through the leak detection groove 7. do.

The leaked water that has flowed down to the bottom plate 8 further passes through a leak detection pipe 9 and is detected by detection equipment. As shown in the figure, the leak detection pipe 9 is connected to a water collection hole 14 bored on the bottom plate 8 at the lowest end of the leak detection groove 7 that communicates with the vertical direction, and the other end is provided with a leak detection sensor. It is connected to the equipped detection equipment. In FIG. 2, two adjacent vertical members 5,
Two leak detection pipes 9, 9' are provided corresponding to the two vertical leak detection grooves 7, 7' formed between the two vertical members 5, 5'. Since all of the vertical and horizontal leak detection grooves existing between the compartments are communicated through the small holes 6, there may be only one leak detection pipe for collecting water leakage from this section.

(Effects of the Invention) Since the storage pool according to the present invention has the above-described structure, it exhibits the following special effects.

The member forming the leakage detection groove 7 is a reinforcing rib 3 assembled in advance on the side surface of the frame 1 and the main body of the lining panel 2, and the lining panel 2 can be lined by simply fitting it into each grid of the frame 1 from the inside of the pool. Since the panel 2 can be firmly temporarily fastened and the leak detection groove 7 can be formed at the same time, the work of fastening temporary bolts and assembling the leak detection groove 7 on the back side of the panel can be omitted, as required in the past.

Therefore, as shown in FIG. 3, there is no need to provide a working hole 54 in the lining material, which greatly simplifies construction and quality control. In particular, when constructing the side wall, it is possible to assemble the side wall and the detection groove 7 only by working from inside the pool.

In addition, since the lining panel material is a large number of the same lining panel material having the standard dimensions and the same dimensions, it is easy to sort the panels 2 according to their parts on site. In addition, as a standard, it is suitable for mass production in factories, reducing manufacturing costs and achieving uniform quality through mass production.

Furthermore, in the structure of the present invention, the lining panel 2, which is the main part of the pool, is often manufactured in advance at a factory with well-equipped processing equipment and environment, and is less likely to be constructed on-site with poor working conditions such as scaffolding. This is extremely advantageous in terms of quality and construction. That is, lining panel 2
The work of assembling the reinforcing ribs 3 to the main body is carried out at the factory, and each block can be delivered to the site as a semi-finished product. Therefore, accuracy is better than on-site processing and welding, and defects such as distortion can be reduced.

In this way, the proportion of on-site work can be reduced, which has the effect of shortening the construction period.

Furthermore, the lining panel 2 has reinforcing ribs 3.
Because it is assembled, it is strong against external forces,
It has strong resistance to damage, deformation, and distortion during transportation from the factory to the site. In addition, even when finishing by placing secondary concrete in the gap between the stretched lining panel 2 and the reinforced concrete wall 12, the lining panel 2 itself has enough strength to withstand the pressure, so the secondary concrete There is no need to newly provide a formwork for pouring concrete, and the lining panel 2 itself can be used as a formwork, which can contribute to reducing construction costs.

Furthermore, in the leakage detection mechanism according to the present invention,
Water leakage that occurs in the section between the adjacent vertical members 5 and 5' is collected by the leakage detection piping 9 installed at the bottom of that section, and the detection mechanism is independent from other sections, so in the unlikely event of an emergency, Even if a leakage accident occurs, the location of the leakage can be quickly identified. In other words, it is no longer necessary to trace the weld line over a wide range of the entire side wall as in the past, and this is highly effective in maintenance and safety management of the storage pool.

As is clear from the above description, the storage pool side wall structure according to the present invention has good construction accuracy, simplifies work, shortens the construction process, and can quickly prevent leakage. It has many advantages such as being compatible with

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the side wall structure of a storage pool according to the present invention, with a corner of the pool partially cut away and a part of a panel 2 removed. . FIG. 2 is a partially cut away and enlarged perspective view of one embodiment of the bottom corner of the storage pool. FIG. 3 is a perspective view showing the structure of a conventional storage pool. 1... Panel mounting frame, 2... Lining panel, 2a... Flat panel, 2b... Corner panel,
3... Reinforcement rib, 4... Horizontal member, 5, 5'... Vertical member, 6... Small hole, 7, 7'... Leak detection groove, 8... Bottom plate,
9, 9'... Leak detection piping, 10... Concrete foundation, 11... End face of panel mounting frame, 12... Reinforced concrete wall, 13... Welding line, 14... Water collection hole, 50... Concrete frame, 51... Lining material, 52... Frame, 53...welding line, 54...opening part.

Claims (1)

[Claims] 1 A panel mounting frame 1 is constructed by joining shaped steel materials such as angle iron and channel steel in a lattice shape on the foundation bottom plate of the storage pool, and reinforcing ribs 3 that fit into the inner edges of each lattice are assembled to form a predetermined shape. While laying the lining panel 2 on the panel mounting frame 1,
The side walls of the storage pool are integrally formed by butt welding the peripheral edges of each lining panel 2 using the panel mounting frame 1 as a backing material, while the horizontal members 4 of the panel mounting frame 1 are vertically welded at both ends. By drilling the communicating small holes 6, the minute gap formed between the side surface of the vertical member 5 of the panel mounting frame 1 and the side surface of the reinforcing rib 3 of each lining panel 2 is made to communicate in the vertical direction. A side wall structure of a storage pool equipped with a leakage detection mechanism, characterized in that the gap is formed as a leakage detection groove 7, and a leakage detection piping 9 is led out from a bottom plate 8 located at the lowest end of this groove.