JP2008203194A - Radiation shielding structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the earthquake resistance of a radiation shielding structure. <P>SOLUTION: The radiation shielding structure includes a shield 2 for shielding radiation, and a strength member for supporting the shield 2. The strength member 3 has a cover member 31 for covering an arrangement space of the shield 2, and the shield 2 is arranged in the space covered with the cover member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a radiation shielding structure, and more particularly to a radiation shielding structure for securing a work environment by shielding radiation in a high-dose atmosphere.

Conventionally, a radiation shielding structure for securing a working environment has been installed in a high-dose atmosphere such as a nuclear reactor, and the working environment is secured by shielding radiation toward the work site with the radiation shielding structure. is doing.
For example, Patent Document 1 discloses a radiation shielding structure in which a plurality of strip-shaped shielding blocks are stacked on a shielding support base. According to such a radiation shielding structure, it is possible to install the radiation shielding structure at an arbitrary place in a high-dose atmosphere, and it is easy to ensure a working environment in a narrow space.
JP 2003-262697 A

  However, the retrofitted radiation shielding structure as in Patent Document 1 does not sufficiently take measures against strong vibration such as an earthquake. For example, in Patent Document 1, a lateral displacement prevention portion that suppresses lateral displacement of a shield block is welded to a side surface of the block of the shield. This lateral displacement prevention portion is a shield block at the time of assembling a radiation shielding structure. Can be prevented, but it is not sufficient for strong vibrations such as earthquakes. Even if the radiation shielding structure collapses due to an earthquake or the like, there is no direct effect on the operation of the nuclear reactor, but a long time and great effort are required to secure the working environment again. It is important to secure the work environment after the earthquake in order to quickly carry out recovery work after the earthquake. The radiation shielding structure not only secures the work environment in normal times but also ensures the work environment in an emergency. Is also desired.

  The present invention has been made in view of the above-described problems, and an object thereof is to improve the earthquake resistance of a radiation shielding structure.

In order to achieve the above object, the present invention provides a radiation shielding structure including a shielding body that shields radiation and a strength member that supports the shielding body, wherein the strength member is an arrangement space of the shielding body. And the shield is disposed in a space covered by the covering member.
According to the present invention having such characteristics, the shield is covered with the covering member of the strength member.

  Moreover, in this invention, the structure that a some shield is arrange | positioned in the space covered with the said covering member is employ | adopted.

  In the present invention, the plurality of shields employ a configuration in which a boundary region formed between the shields is arranged so as to be discontinuous with respect to the radiation direction of the radiation in the arrangement space. .

  Moreover, in this invention, the structure that the shielding body arrange | positioned in the space covered with the said coating | coated member is a block which consists of lead is employ | adopted.

  Moreover, in this invention, while connecting the said intensity | strength member to another member, the connection part which has the storage space which accommodates the said shielding body is provided, and the structure that the said shielding body is accommodated in the said accommodation space is employ | adopted. .

  Moreover, in this invention, the structure that the shielding body accommodated in the storage space of the said connection part is the grain which consists of lead is employ | adopted.

According to the present invention, the shielding member arranged in the predetermined arrangement space is covered by the covering member of the strength member. That is, the shielding member arranged in the arrangement space is covered with the covering member of the strength member without being exposed. For this reason, even when strong vibration such as an earthquake is applied, the shielding member arranged in the arrangement space by the covering member is prevented from collapsing.
Therefore, according to the present invention, it is possible to improve the earthquake resistance of the radiation shielding structure.

  Hereinafter, an embodiment of a radiation shielding structure according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.

FIG. 1 is a plan view of a high-dose tank installation section S in which a plurality of radiation shielding structures 1 of this embodiment are installed.
As shown in FIG. 1, the high-dose tank installation unit S has a configuration in which two high-dose tanks T are installed inside a room H surrounded by a concrete wall S1. The high-dose tank T is a tank for storing slug generated in the pressure vessel of the nuclear reactor, and is installed on a base (not shown) formed of concrete.

  In addition, the periphery of each high-dose tank T is surrounded by a plurality of radiation shielding structures 1 of the present embodiment. Although not shown in FIG. 1, maintenance devices such as valves and filters are installed around the high-dose tank T, and a radiation shielding structure is provided between these maintenance devices and the high-dose tank T. 1 is installed.

FIG. 2 is a perspective view of the radiation shielding structure 1. FIG. 3 is a cross-sectional view of the radiation shielding structure 1.
As shown in these drawings, the radiation shielding structure 1 includes a shielding body 2 that shields radiation from the high-dose tank T and a strength member 3 that supports the shielding body 2.

The shield 2 is a block made of lead, and is formed in a size of, for example, 250 mm × 150 mm × 40 mm. A plurality of shields 2 are arranged in a predetermined arrangement area. In the radiation shielding structure 1 of this embodiment, the shielding bodies 2 are arranged in two rows in the thickness direction of the radiation shielding structure 1 (radiation direction of radiation). Further, in each row, a plurality of shields 2 are laid out in the extending direction and the height direction of the radiation shielding structure 1.
Then, the second row of shields so that the boundary region formed between the shields 2 arranged in the first row is not continuous in the thickness direction of the radiation shield structure 1 (radiation direction of radiation). 2 are arranged. That is, the plurality of shields 2 are arranged such that boundary regions formed between them are discontinuous with respect to the radiation direction in a predetermined arrangement space.
The shape and weight of the shield 2 are not particularly limited, but the shape of each shield 2 is a rectangular parallelepiped in consideration of the ease of assembly of the radiation shield structure 1. The weight of 2 is preferably a weight that can be transported by one worker (for example, 20 kg or less).

  The strength member 3 includes a covering member 31 that covers the arrangement space of the shield 2 (that is, the entire plurality of arranged shields 2), a support member 32 that supports the covering member 31, and a reinforcing member 33 that reinforces the covering member 31. It is equipped with.

The covering member 31 covers the lower surface of the arrangement space of the shield 2 and supports the weight of the shield 2, a plurality of side plates 312 covering the side surfaces of the arrangement space of the shield 2, and the upper surface of the shield 2 And a ceiling plate 313 that covers the ceiling.
As the cradle 311, a steel plate can be used, and as the side plate 312 and the ceiling plate 313, for example, an iron plate having a thickness of about 4 mm can be used. Then, a closed space (space) is formed by welding the cradle 311, each side plate 312, and the ceiling plate 313, and the plurality of shields 2 are arranged in this space.
Note that the height of the cradle 311 is set lower than the height of the base on which the high-dose tank T is installed in order to prevent radiation from being transmitted to the outside of the radiation shielding structure 1 through the cradle 311. The

The support member 32 includes a column 321 erected along the side surface of the covering member 31 and an oblique column 322 that supports the covering member 31 obliquely via the column 321. As these support columns 321 and the oblique columns 322, steel shapes can be used.
The column 321, the oblique column 322, and the cradle 311 are disposed on the floor surface S <b> 2 of the high-dose tank installation unit S via a plurality of base plates 4 fixed by chemical anchors. These base plates 4 ensure the level of the radiation shielding structure 1.
As shown in FIG. 1, the oblique column 322 is not necessarily required, and may be fixed to the wall surface S3 of the concrete wall S1 instead of the floor surface S2.

  The reinforcing member 33 is installed extending vertically and horizontally so as to cover the boundary portion between the side plates 312 of the covering member 31. The reinforcing member 33 is supported by the support column 321 of the support member 32. Further, as the reinforcing member 33, a shape steel can be used.

FIG. 4 is an enlarged cross-sectional view of a location (A in FIG. 1) connecting the radiation shielding structure 1 and another radiation shielding structure (other member). In FIG. 4, illustration of other radiation shielding structures is omitted.
As shown in FIG. 4, the radiation shielding structure 1 of the present embodiment has a connection portion 5 for connecting to another radiation shielding structure.
The connection part 5 is provided with the main-body part 51 which consists of an H-shaped shaped steel standing. Moreover, the storage space 54 formed by the recessed part on the opposite side to the high dose tank T of the main-body part 51 being covered with the side plate 52, the ceiling plate 53, and the bottom plate not shown is provided. The storage space 54 is filled (stored) with grains made of lead as the shield 7.
As shown in FIG. 1, the radiation shielding structure 1 is partially connected to another radiation shielding structure 1 through such a connection portion 5.

  According to the radiation shielding structure 1 of the present embodiment configured as described above, the radiation emitted from the high-dose tank T is shielded by the shielding bodies 2 and 7, and therefore, radiation outside the radiation shielding structure 1. The amount can be reduced, and a work area can be secured.

In the radiation shielding structure 1 of the present embodiment, the strength member 3 includes the covering member 31 that covers the arrangement space of the shielding body 2, and the shielding body 2 is arranged in the space covered by the covering member.
According to such a radiation shielding structure 1 of this embodiment, the shielding body 2 arranged in a predetermined arrangement space is covered by the covering member 31 included in the strength member 3. That is, the shield 2 arranged in the arrangement space is covered with the covering member 31 of the strength member 3 without being exposed. For this reason, even when strong vibration such as an earthquake is applied, the shielding member 2 arranged in the arrangement space by the covering member 31 is prevented from collapsing.
Therefore, according to the radiation shielding structure 1 of the present embodiment, it is possible to improve the earthquake resistance of the radiation shielding structure.

  Further, in the radiation shielding structure 1 of the present embodiment, a plurality of shielding bodies 2 are arranged in a space covered with the covering member 31. For this reason, each shielding body 2 can be reduced in size, and the conveyance at the time of an assembly becomes easy.

Further, in the radiation shielding structure 1 of the present embodiment, the plurality of shielding bodies 2 arranged in the arrangement space are such that the boundary region formed between them is discontinuous with respect to the radiation direction of the radiation in the arrangement space. It is arranged to become.
For this reason, it is possible to prevent radiation from leaking to the outside of the radiation shielding structure 1 through the boundary region, and it is possible to further reduce the radiation dose in the work environment.

  Moreover, in the radiation shielding structure 1 of this embodiment, the shielding body 2 disposed in the space covered with the covering member 31 is a block made of lead. For this reason, the shield 2 can be easily transported during assembly, and the boundary region formed between the shields can be relatively easily discontinuous with respect to the radiation direction in the placement space. can do.

In addition, the radiation shielding structure 1 of the present embodiment includes the connection portion 5 having the storage space 54 for connecting the strength member 3 to another member (other radiation shielding structure) and storing the shielding body 7. The shield 7 is stored in the storage space 54.
For this reason, it can prevent that a radiation permeate | transmits the connection part 5, and can prevent that a radiation leaks from the location where the radiation shielding structure 1 is connected with another member.
In addition, in the radiation shielding structure 1 of this embodiment, the shielding body 7 accommodated in the accommodation space 54 of the connection part 5 is comprised with the particle | grains which consist of lead. For this reason, irrespective of the shape of the connection part 5, the storage space 54 can be easily filled with the shield 7 at the time of assembly.

  When assembling the radiation shielding structure 1 of the present embodiment described above, the cradle 311 of the strength member 3 and the side plate 312 are welded from the inside of the arrangement space in a state where the shielding body 2 is not arranged. After that, the shield 2 is disposed, and finally the ceiling plate 313 may be welded to the side plate 312.

  As mentioned above, although preferred embodiment of the radiation shielding structure which concerns on this invention was described referring drawings, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above-described embodiment, the configuration in which the radiation shielding structure is erected and used as the wall has been described. However, the present invention is not limited to such an application. For example, as shown in FIG. 5, the radiation shielding structure 1 is laid on the lid T1 of the high-dose tank T, and the radiation shielding structure 1 is disposed. It can also be used as a walkway.

  Moreover, in the said embodiment, the several shielding body 2 is arranged over 2 rows in the thickness direction (radiation | emission direction of a radiation) of the radiation shielding structure 1, and between the shielding bodies 2 arranged in the 1st row | line | column By arranging the shields 2 in the second row so that the boundary region formed between them is not continuous in the thickness direction of the radiation shield structure 1 (radiation direction of radiation), the plurality of shields 2 are: The boundary region formed between each other was discontinuous with respect to the radiation direction in a predetermined arrangement space. However, the present invention is not limited to this, and as shown in FIG. 6, a shield 8 having a crank shape in cross section may be stacked in the arrangement section. When the shields 8 having such a crank-shaped cross section are stacked, the boundary region can be made non-continuous with respect to the radiation direction in a predetermined arrangement space, and only one row of shields is provided. It will be better if it is arranged.

  Moreover, in the said embodiment, the example which uses the radiation shielding structure 1 for the use which shields the radiation radiated | emitted from the high dose tank T was demonstrated. However, the present invention is not limited to this, and can be used for applications that shield radiation from objects that emit other high-dose radiation. Moreover, you may use for the use which shields the radiation from the object which radiates | emits a low dose of radiation.

It is a top view of the high dose tank installation part in which the radiation shielding structure which is one Embodiment of this invention was installed. It is a perspective view of the radiation shielding structure which is one Embodiment of this invention. It is sectional drawing of the radiation shielding structure which is one Embodiment of this invention. It is sectional drawing for demonstrating the connection part with which the radiation shielding structure which is one Embodiment of this invention is provided. It is sectional drawing for demonstrating the other use of the radiation shielding structure which is one Embodiment of this invention. It is sectional drawing which shows the modification of the shielding body with which the radiation shielding structure which is one Embodiment of this invention is provided.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Radiation shielding structure, 2 ... Shield, 3 ... Strength member, 31 ... Cover member, 32 ... Support member, 33 ... Reinforcement member, 4 ... Base plate, 5 ... Connection part, 54 ...... Storage space, 7 ... Shield, 8 ... Shield

Claims (6)

A radiation shielding structure comprising a shielding body that shields radiation and a strength member that supports the shielding body,
The strength member includes a covering member that covers an arrangement space of the shield,
The radiation shielding structure, wherein the shielding body is disposed in a space covered by the covering member.   The radiation shielding structure according to claim 1, wherein a plurality of shielding bodies are arranged in a space covered by the covering member.   The radiation shield according to claim 2, wherein the plurality of shields are arranged such that a boundary region formed between them is discontinuous with respect to the radiation direction of the radiation in the placement space. Structure.   The radiation shielding structure according to claim 1, wherein the shield disposed in the space covered by the covering member is a block made of lead.   The connecting member having a storage space for connecting the strength member to another member and storing the shielding body, wherein the shielding body is stored in the storage space. The radiation shielding structure described in 1. 6. The radiation shielding structure according to claim 5, wherein the shielding body housed in the housing space of the connection portion is a grain made of lead.

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