JP7426521B1 - Underground shelter and its construction method - Google Patents

Abstract

[Problem] To obtain an underground shelter that is easy to construct and inexpensive. [Solution] This shelter 1 is formed by combining multiple sets in the y direction of side wall parts 10A and 10B provided spaced apart on both sides in the x direction and a top plate 11 installed between these on the upper side. be done. A bottom plate 12 is formed between the side wall portions 10A and 10B at the bottom. The side wall portions 10A (10B) and the top slab 11 are manufactured as concrete blocks (precast blocks) manufactured using formwork at a factory different from the construction site. In Figure 1(a), six sets of these are used, but this number is arbitrary; if this number is large, the shelter 1 will be long in the y direction, and if this number is small, the shelter 1 will be short in the y direction. can do. [Selection diagram] Figure 1

Description

The present invention relates to an underground shelter, which is a building installed underground for evacuation, and a method for constructing the same.

Various types of shelter structures have been proposed to prevent damage caused by natural disasters such as tsunamis and radiation exposure caused by nuclear weapons. Of these, from the perspective of shielding from radioactivity, etc., it is effective to provide such a shelter underground. Concrete, which is generally used as a building material, has the mechanical strength required for buildings and also has a certain ability to shield neutrons, so it is also used as the main material for shelters. preferable. Shelters with such a structure are described in, for example, Patent Documents 1 and 2. Furthermore, as described in Patent Document 3, heavy concrete with enhanced ability to shield gamma rays and the like is also known as concrete for radiation shielding.

Japanese Patent Application Publication No. 6-346478 JP2007-297898A Japanese Patent Application Publication No. 2014-231450

If such a shelter is to be installed not as a large public facility, but in particular for an ordinary house, that is, if a small shelter is to be installed attached to a private residence, it is required that it can be constructed at a low cost. be done. On the other hand, in the technologies described in Patent Documents 1 and 2, for example, it is difficult to construct a complex structure underground, which differs greatly from that of a typical building. It was difficult to build cheaply.

The present invention has been made in view of this situation, and an object of the present invention is to solve the above problems.

The present invention is an underground shelter installed underground, and the space inside the underground shelter is arranged in a first direction perpendicular to a vertical direction, and in a vertical direction and the first direction. and a second direction perpendicular to the second direction, and in the second direction, one end side and the other end side are underground , and the one side after cutting the ground. a side wall section installed on the bottom surface after cutting the ground so as to abut on the side surface of the other side, and the side wall section on the one end side and the side wall section on the other end side. It is characterized in that a plurality of combinations of top slabs , which are provided to connect the upper sides of the side wall portions and are made of heavy concrete , are connected along the first direction .
The present invention is characterized in that tension members are fixed that pass through the plurality of side wall portions or the plurality of top plates along the first direction.
The present invention provides a method for constructing the underground shelter, in which the side wall portion and the top plate are manufactured as precast blocks, and on the bottom surface, one of the one in the combination is manufactured as a precast block. The side wall portion on the end side and the side wall portion on the other end side are in contact with the side surface on the one side and the side surface on the other side, respectively, and are spaced apart in the second direction. a side wall arrangement step of arranging a plurality of sets of side wall parts, and installing each of the corresponding top plates above the side wall part on the one end side and the side wall part on the other end side in each of the combinations; and a bottom plate installation step of installing a bottom plate at the bottom between the side wall part on the one end side and the side wall part on the other end side. Features.
In the present invention, after the top plate fixing step, the plurality of side wall parts or the plurality of top plates are penetrated along the first direction. The present invention is characterized by comprising a tensioning step of applying prestress along the first direction to the plurality of side walls or the plurality of top plates via the tension material after installing the tension material.

According to the present invention, it is possible to obtain an underground shelter that is easy to construct and inexpensive.

1 is a perspective view (a) and a sectional view (b) of an underground shelter according to an embodiment of the present invention. FIG. 1 is a perspective view of members constituting an underground shelter according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the construction method of the underground shelter based on embodiment of this invention. 1 is a sectional view showing a method of constructing an underground shelter according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing the structure around the tendons in the method of constructing an underground shelter according to the embodiment of the present invention.

An underground shelter according to an embodiment of the present invention will be described. FIG. 1 shows a perspective view (a) and a cross-sectional view (b) of this underground shelter (shelter) 1. Here, in the perspective view (a), only the shelter 1 is shown, and in the cross-sectional view (b), the form in the ground G of the cross section perpendicular to the y direction (first direction) is shown. ing. The vertical direction is the z direction.

As shown in FIG. 1(a), this shelter 1 has side walls 10A and 10B provided spaced apart on both sides in the x direction (second direction), and a wall installed between these on the upper side. A plurality of top plates 11 are formed in combination in the y direction. A bottom plate 12 is formed between the side wall portions 10A and 10B at the bottom. Here, six sets of side wall parts 10A, 10B and top plate 11 are used, but in reality, this number corresponds to the length in the y direction of the internal space of shelter 1, and this number is set as appropriate. As shown in FIG. 1(b), the side walls 10A, 10B and the top plate 11 are connected by a connecting tool 20. As shown in FIG.

Note that in FIG. 1A, the shelter 1 is open on both sides in the y direction, but in reality, end walls are provided to close these openings. The entrance to the interior of the shelter 1 may be formed by providing an opening on the upper side in FIG. 1(a) after constructing the structure in FIG. 1(a), but the entrance may also be provided in this end wall. . Such entrances and exits can be set as appropriate. In this case, this end wall seals the internal space instead of the side wall parts 10A and 10B on both end sides (positive side, negative side) in the y direction in FIG. It is arranged like this. As shown in FIG. 1(b), in a cross section perpendicular to the y direction, this space is partitioned by a pair of side walls 10A, 10B, a top plate 11, and a bottom plate 12.

The six side wall parts 10A, the six side wall parts 10B, and the six top plates 11 in FIG. 1(a) have the same shape. FIG. 2 is a perspective view showing these individual shapes. In reality, the side wall portions 10A and 10B have the same shape, and in FIG. 1A, they are placed in opposite directions in the x direction (second direction) and spaced apart from each other. That is, all the side wall parts 10A and all the side wall parts 10B (12 pieces in total) have the same shape.

The side wall portion 10A (10B) and the top plate 11 shown in FIG. 2 are manufactured as concrete blocks (precast blocks) manufactured using formwork at a factory different from the construction site. In Figure 1(a), six sets of these are used, but this number is arbitrary; if this number is large, the shelter 1 will be long in the y direction, and if this number is small, the shelter 1 will be short in the y direction. can do. That is, by using the same side wall portions 10A and the like and adjusting only this number, the length (length in the y direction) that the space inside the shelter extends can be set. The size of individual houses varies, and the size (length) of the shelter that can be constructed also varies accordingly, but this length can be easily set by the number of combinations mentioned above. This shelter 1 can be made inexpensive.

As shown in FIG. 1(b), the bottom plate 12 is formed so as to be embedded between the side wall portion 10A and the side wall portion 10B which are spaced apart on the bottom surface side. As will be described later, the bottom slab 12 can be manufactured not from a precast block but by pouring concrete after installing the side walls 10A and 10B at the construction site. However, the bottom plate 12 manufactured as a precast block may be arranged as shown in FIG.

As described above, by constructing the shelter 1 from many members and constructing at least the side wall portions 10A, 10B and the top plate 11 from precast blocks, the weight of these components can be reduced. This makes it easy to transport them, for example in narrow spaces or places with height restrictions. Further, at the construction site, there is no need to pour concrete to construct these members. Furthermore, by forming the side wall portion 10A (10B) and the top slab 11 as separate precast blocks as shown in FIG. 2, each of them can be constructed from different materials (different types of concrete).

In the form of FIG. 1(b), the radiation to be shielded mainly enters the interior of the shelter 1 from the upper side, so that the top plate 11 in FIG. 1 is particularly required to have a high shielding ability against radiation. Therefore, as the concrete constituting the top slab 11, heavy concrete as described in Patent Document 3, for example, can be used. Heavy concrete is a concrete material in which aggregate containing iron is mixed into normal concrete, and has a higher specific gravity than normal concrete and has the ability to shield against neutrons, gamma rays, etc. On the other hand, precast blocks made of heavy concrete are heavy, making transportation and construction difficult. On the other hand, in the configuration shown in FIG. 1, each of the top slabs 11 can be individually miniaturized, and as a result, their weight can be reduced, making their transportation and construction easier. The same applies to the case where the side walls 10A and 10B are made of heavy concrete.

The method of constructing this shelter 1 will be explained below. As described above, since this shelter 1 is constructed using precast blocks, it can be constructed using the commonly known PC (precast concrete) construction method. This construction work is performed as described below. 3 and 4 are a perspective view and a sectional view, respectively, illustrating this construction method. Here, the description of the ground G is omitted in the perspective view (FIG. 3).

Here, first, as shown in FIGS. 3(a) and 4(a), after the ground G is cut, six side walls 10A and 10B are formed on the bottom surface thereof, corresponding to the bottom slab 12. They are installed at predetermined positions with intervals (side wall placement process). Thereafter, as shown in FIGS. 3(b) and 4(b), six top plates 11 are arranged and fixed from above the above structure (top plate fixing step). As mentioned above, the top plate 11 is required to have a particularly high radiation shielding ability, and is therefore made of heavy concrete. At this time, a well-known method can be used as a fixing method between them. In FIGS. 3(b) and 4(b), a metal connector 20 is used, and for example, a bolt passing through the connector 20 is connected to a nut embedded in the side walls 10A, 10B and the top plate 11. These can be fixed by screwing them together with bolts and nuts (both not shown). This fixing is performed for each combination (6 sets in this example) of the side wall portions 10A, 10B and the top plate 11 side.

Note that in FIG. 3(b), the side walls 10A, 10B and the top plate 11 are connected from the inner side using the connecting tool 20, but they can also be connected using other methods. For example, the top plate 11 may be fixed to the lower side walls 10A, 10B using bolts or the like from above the top plate 11. Alternatively, the side wall portions 10A, 10B and the top plate 11 may be connected from the outside using a connecting tool.

Next, as shown in FIG. 3C and FIG. The work is carried out (tensioning process).Here, a PC steel rod (tensioning material) 30, which is a steel material passing through these in the y direction, is used. It is a sectional view along the y direction and the z direction showing the structure related to the PC steel bar 30 in area A.Here, the top plate located on the most positive side in the y direction (the front side in the paper in FIG. 3(c)) 11 and the PC steel rod 30 are shown.

All the top plates 11 are formed with PC steel rod through holes 11A that allow the PC steel rods 30 to penetrate in the y direction so as to communicate with each other in the state shown in FIG. 3(c). The PC steel rod 30 is installed so that the PC steel rod 30 protrudes. As shown in FIG. 5, a plate-shaped anchor plate 31 and a nut 32 are sequentially attached to the tip of the protruding PC steel rod 30, and in particular, the nut 32 is screwed onto the PC steel rod 30. In addition, in FIG. 3(c) and FIG. 4(c), descriptions of those other than the PC steel rod 30 are omitted, and in FIGS. 3(c) and 4(c) other than those shown in FIG. The description of the PC steel rod 30 is also omitted.

Although FIG. 5 shows the structure of the end of the PC steel bar 20 on the positive side in the y direction, the same applies to the end on the negative side of the y direction. Therefore, in the tensioning work, the nuts 32 on both end sides are tightened, and a prestress can be applied to the six top plates 11 along the y direction by the anchor plates 31 on both sides. As is well known, the strength of the top plate 11 can be increased by this prestress.

In FIG. 5, the structure related to the PC steel bar 20 in the upper left area A in FIGS. 3(c) and 4(c) is shown, but regarding the other three PC steel bars 20 in FIG. 3(c), The same is true. That is, by this tensioning step, prestress can be applied to the top plate 11 and the side wall portions 10A and 10B along the y direction (the stacking direction), thereby increasing their strength. Note that if a hole is provided in the side walls 10A, 10B and the top plate 11 to communicate the inside of the PC steel bar through hole 11A with the outside in the x direction or the z direction, the PC steel bar through hole 11A can be opened from this hole after tension work. The inside can be filled with mortar.

Thereafter, as shown in FIGS. 3(d) and 4(d), concrete is poured between the side walls 10A and 10B adjacent in the x direction to form the bottom slab 12. (Bottom plate installation process). In addition, concrete may be placed appropriately below the side walls 10A and 10B. In this case, the concrete forming the side walls 10A, 10B and the bottom plate 12 may be ordinary concrete (reinforced concrete) rather than heavy concrete.

Further, when the bottom plate 12 is also configured as a precast block, the bottom plate 12 may be arranged as shown in FIGS. 3(d) and 4(d). In this case, mortar can be applied between the bottom plate 12 and the side walls 10A, 10B to seal the space between them. Further, the bottom plate 12 may be divided as appropriate in the y direction, and in this case, it is not necessary that the divisions be the same as the side wall portions 10A and 10B (six in the figure).

Thereafter, an entrance/exit to the interior of the shelter 1 is appropriately formed as described above. As described above, the shelter 1 can be constructed using the side wall portions 10A, 10B and the top plate 11 formed as precast blocks. For this reason, this shelter can be constructed in a shorter construction period than when constructing a shelter with the same final structure by casting on site, or when using connectors to join precast blocks together. By making each member a precast block, each member can be made uniform and of high quality. In addition, by constructing only the members (top plate 11) that particularly require radiation shielding ability from heavy concrete, transportation and construction of each member become easier.

Further, in the above example, the side wall portions 10A (10B) and the top plate 11 have the shapes shown in FIG. 2, but these shapes are appropriately set according to the shape of the space inside the shelter 1. Further, the distance between the side wall portions 10A and 10B in the x direction or the width of the top plate 11 are also the same. However, by increasing the distance between the side wall portions 10A and 10B (the width of the bottom plate 12), each side wall portion 10A (10B) can be made smaller and lighter. In addition, since the shelters 1 having different widths in the x direction can be constructed by changing this interval, they can be constructed using the common side wall portion 10A (10B), and from this point of view, the shelter 1 can be made at low cost. It can be done.

The present invention has been described above based on the embodiments. It will be understood by those skilled in the art that this embodiment is merely an example, and that various modifications can be made to the combinations of these components, and that such modifications are also within the scope of the present invention.

1 Shelter (underground shelter)
10A, 10B Side wall portion 11 Top plate 11A PC steel bar through hole 12 Bottom plate 20 Connector 30 PC steel bar (tension material)
31 Anchor plate 32 Nut

Claims (4)

An underground shelter installed underground,
The space inside the underground shelter extends in a first direction perpendicular to the vertical direction, and in a second direction perpendicular to the vertical direction and the first direction,
In the second direction, spaced apart from each other, underground on one end side and the other end side , respectively on the side surface of the one side and the side surface of the other side after cutting the ground. A side wall part installed on the bottom surface after cutting the ground so as to be in contact with it ,
a top plate formed of heavy concrete and configured to connect the side wall portion on the one end side and the upper side of the side wall portion on the other end side;
An underground shelter comprising a plurality of combinations connected along the first direction. 2. The underground shelter according to claim 1 , wherein tension members are fixed to extend through the plurality of side walls or the plurality of top plates along the first direction. A method for constructing an underground shelter according to claim 1 or 2, comprising:
manufacturing the side wall portion and the top plate as a precast block;
On the bottom surface, along the first direction, the side wall part on the one end side and the side wall part on the other end side of the combination are connected to the side wall part on the one side and the side wall part on the other side. a side wall part arranging step of arranging a plurality of sets in a form that are in contact with the side surfaces of and spaced apart in the second direction;
a top plate fixing step of installing and fixing each of the corresponding top plates above the side wall portion on the one end side and the side wall portion on the other end side in each of the combinations;
a bottom plate installation step of installing a bottom plate at the bottom between the side wall portion on the one end side and the side wall portion on the other end side;
A method for constructing an underground shelter, comprising: After the top plate fixing step,
After installing a tendon that penetrates the plurality of side wall parts or the plurality of top plates along the first direction with respect to the plurality of side wall parts or the plurality of top plates, 4. Construction of an underground shelter according to claim 3 , further comprising a tensioning step of applying prestress along the first direction to the plurality of side walls or the plurality of top plates. Method.

Images