JP6356939B1 - Semi-underground shelter construction method - Google Patents

Abstract

Providing a high-strength shelter that is easy to install and has reduced costs.
The shelter 1 includes a main body 100 installed on a foundation 10 and a concrete layer 4 provided on the outer periphery of the main body 100, and the main body 100 includes an iron casing 2 including a ceiling plate 22 and a cylindrical side plate 21. And a plurality of annular shapes provided in the circumferential direction on the outer surface of the side plate 21 with a diameter set to a predetermined range with respect to the inner diameter of the housing 2 and the door 5 provided on the ground portion F of the housing 2 In the construction method of the shelter, the main body 100 is manufactured at the factory, the hole H is formed, the base 10 is constructed at the bottom of the hole H, the main body 100 is installed on the base 10, and the side plate 21 A formwork T is built around, concrete is placed and cured, the formwork T is removed, and the gap is filled with soil or concrete.

Description

  The present invention relates to a shelter in a disaster-predicted area such as a tsunami.

  The total number of dead and missing people who died due to the Great East Japan Earthquake that occurred on March 11, 2011 and the accompanying great tsunami reached more than 20,000 people. Is expected to occur. For example, according to the announcement by the Cabinet Office, there were about 6,400 deaths in Aichi Prefecture due to tsunami and about 1,800 deaths due to fire, and 95,000 people in nearby Shizuoka Prefecture. Expected death to exceed. In recent years, awareness of earthquake and tsunami countermeasures has increased.

  In order to prepare for the Nankai Trough Earthquake, which is expected to occur in the future, as a measure to save lives by itself, demand for shelters is increasing in private homes. Various inventions have been proposed as shelters for evacuating in the event of an earthquake and tsunami, such as a method of fixing to a foundation and a floating type.

  As a shelter to be fixed to a foundation, one using a composite structure composed of an iron plate and concrete for a shelter body is known.

  In Patent Document 1, in order to provide an underground shelter excellent in earthquake resistance and waterproofness, a box-shaped shelter body made of high-strength concrete is integrated on a pressure plate supported by a plurality of piles driven into the ground. There is disclosed a structure in which the outer surface of the shelter body is covered with an iron plate.

Japanese Patent Laid-Open No. 2005-240452

  However, the underground shelter disclosed in Patent Document 1 is in a state where the iron plate covering the outer surface of concrete is always in contact with soil containing a large amount of moisture and oxygen, and is always exposed to an environment where corrosion is likely to be promoted. Yes. In order to suppress the corrosion of the iron plate, it is necessary to apply a waterproof coating or the like to the outer surface of the iron plate, which causes a high cost. Also, when placing concrete in the gap between the steel plate and the formwork that forms the ceiling, it is necessary to start up the support work from the floor in order to support the formwork that directly receives the weight of the concrete. Becomes longer, the process becomes complicated, and the construction cost increases. In such a shelter with a long construction period and high cost, it is difficult to spread it to general households.

  An object of the present invention is to provide a high-strength shelter that is easy to construct and has a reduced cost.

The invention according to claim 1 is a semi-underground shelter construction method, comprising assembling a main body, filling an internal space of a hollow tube with a filler, forming a hole, and a bottom of the hole. A step of constructing, a step of installing the main body on the foundation, a step of building a mold around the side plate of the main body, a step of placing concrete and curing in a space formed in the gap between the mold and the main body, and removing the mold comprises the step of filling the space formed between the concrete layer and the hole with soil or concrete, hollow tubes, provided on the outer surface of the side plate of the main body, the Rukoto are embedded in the concrete layer Features.

According to this configuration, the step of forming the hole, the step of assembling the main body, the step of filling the inner space of the hollow tube with the filler, the step of constructing the foundation at the bottom of the hole, and the main body being installed on the base A step, a step of building a mold around the side plate of the main body, a step of placing and curing concrete in a space formed in the gap between the mold and the main body, a removal of the mold, a concrete layer and a hole Since the step of filling the space formed between the two with soil or concrete is provided, construction at the site is easy and the construction period can be shortened.

It is sectional drawing of the shelter of embodiment of this invention. It is plane explanatory drawing which shows the fixing structure of the door of the shelter of this invention embodiment. It is the side view and sectional drawing of the uppermost hollow tube of the shelter of this invention embodiment, and the lowest hollow tube. It is a front view of the main body which shows the state in which the formwork of this invention embodiment was provided.

A shelter 1 according to an embodiment of the present invention will be described. The shelter 1 includes a foundation 10, a main body 100 installed on the foundation 10, and a concrete layer 4 provided on an outer peripheral portion of the main body 100. Details will be described below.

As shown in FIG. 1, the foundation 10 is provided in the ground, and the main body 100 installed on the foundation 10 includes an above-ground part F and an underground part S. The foundation 10 can be provided in the ground by excavating the ground to a predetermined depth, forming a hole H, and placing concrete on the bottom surface of the hole H. The foundation 10 is preferably finished flat and horizontal. Thereby, the installation work of the main body 100 becomes easy.

The main body 100 has strength that can withstand earthquake force, tsunami wave force, impact force caused by a tsunami drifting object, etc. And a plurality of annular hollow tubes 3 provided in the circumferential direction on the outer surface of the side plate 21.

  The housing 2 includes a bottom plate 23, a ceiling plate 22, and a cylindrical side plate 21. The inner diameter A of the housing 2 is preferably 1.4 m to 3 m. Further, the height of the ground portion F is 140 cm and the height of the underground portion S is 140 cm. By using a small shelter, it is possible to install it in a small site in a short period of time using only small construction machines. As a result, the spread to general households can be promoted.

  The plate thickness of the housing 2 is preferably 2.0 mm to 6.0 mm, and examples thereof include 2.7 mm, 3 mm, and 4 mm. As will be described later, a strength equivalent to a plate thickness of 9 mm can be obtained by appropriately arranging the hollow tube 3 and the supporting members 6U and 6L.

  A plurality of hollow tubes 3 are provided in a state of being fitted in an annular shape in the circumferential direction of the outer surface of the side plate 21. Further, the side plate 21 and the hollow tube 3 are fixed by being welded at appropriate intervals. Thereby, the side plate 21 and the hollow tube 3 can cooperate and can raise intensity | strength and rigidity. The diameter B of the hollow tube 3 can be accurately bent into an annular shape and can be fitted to the outer surface of the housing 2, that is, 16/1000 of the inner diameter A of the housing 2. To 35/1000 is preferred. As shown in FIG. 2, the inner diameter A of the housing 2 is smaller by the thickness of the housing 2 than the inner diameter C of the annular ring formed by bending the hollow tube 3.

  The hollow tube 3 is a general carbon steel pipe for structural use. For example, in JIS G3444 STK500, diameter 48.6 mm, thickness 2.40 mm, pre-plating specification hot dip galvanization specification (JIS H-8641, JIS H-9124) Preferably there is. The cross section is not limited to a circle but may be a square.

  The interval between the hollow tubes 3 in the ground portion F is set to be narrower than the interval between the hollow tubes 3 in the underground portion S. Possible loads acting on the shelter 1 include seismic forces, tsunami wave forces, and impact forces caused by tsunami drifting objects. The seismic force is small in the ground and increases as it approaches the ground surface. Only the ground part F receives the wave force directly from the tsunami and does not act on the underground part. The same applies to the impact force caused by tsunami drifting objects. In other words, the ground portion F is subjected to a larger load than the underground portion S. The thickness of the side plate 21 can be kept thin by making the interval between the hollow tubes 3 in the ground portion F to which a larger load acts than the underground portion S smaller than the interval between the hollow tubes 3 in the underground portion S. Thus, the cost can be further reduced by appropriately setting the interval between the hollow tubes 3.

The internal space 3a of the hollow tube 3 is filled with mortar 3b (filler), and the air in the internal space 3a is discharged. When air is filled in the internal space 3 a of the hollow tube 3, there is a possibility that the air filled by flame heat or the like is ejected toward the concrete layer 4. In this case, the concrete layer 4 is damaged by the jetted air. Further, when the air filled in the internal space 3a is repeatedly compressed and expanded due to changes in the outside air temperature, the hollow tube 3 also repeats compression and expansion at the same time. By repeating this, the concrete layer 4 deteriorates. Therefore, the concrete layer 4 can prevent damage caused by the air blown by filling the internal space 3a of the hollow tube 3 with the mortar 3b, and can suppress deterioration. In addition, the hollow tube 3 and the mortar 3b cooperate to increase the strength and rigidity of the hollow tube 3. In the embodiment of the present invention, the filler is mortar, but may be cement milk.

The support member 6U reinforces the ceiling plate 22, and as shown in FIG. 3, the six support members 6U are equally disposed and fixed in the circumferential direction of the uppermost hollow tube 3U, and have a diameter. They extend horizontally in the center direction and are fixed to each other at the center of the hollow tube 3U. Moreover, it fixes by welding with the ceiling board 22 with a suitable space | interval. That is, the ceiling board 22 has acquired the predetermined | prescribed intensity | strength and rigidity by cooperating with the support material 6U. Thereby, it becomes possible to suppress the deformation | transformation of the ceiling board 22 at the time of concrete placement, and concrete can be directly placed on the upper surface of the ceiling board 22 without giving special reinforcement.

The support material 6L is for suppressing deformation of the main body 100. Thereby, the installation to the foundation 10 becomes easy. Since the structure is substantially the same as that of the support member 6U, description thereof is omitted.

The support members 6U and 6L are preferably general-purpose shape steel.

The concrete layer 4 is for protecting the main body 100 from flame heat, a corrosive environment, a collision caused by a tsunami drifting material, and the like, and is provided on the outer peripheral portion of the main body 100. The thickness of the concrete layer 4 is preferably 15 cm to 30 cm.

In a state where the concrete layer 4 is not provided on the outer peripheral portion of the main body 100, when the main body 100 reaches a predetermined temperature or more due to flame heat, the rigidity of the iron plate or the like constituting the main body 100 is lowered and greatly deformed. When the concrete layer 4 is provided, the temperature rise of the housing 2 can be suppressed and the main body 100 is restrained by the concrete layer 4. As a result, deformation of the main body 100 can be suppressed.

In the ground, the surface and voids of the soil particles contain moisture and oxygen, and the environment is such that the corrosion of the iron plate is very easy to promote. Moreover, when the shelter 1 is installed in a place close to the coast, it is affected by the splash of seawater, and the corrosion of the iron plate is promoted. However, when the concrete layer 4 is provided on the outer periphery, a passive film is formed on the surface of the iron plate due to the alkali of the concrete layer 4, and the corrosion of the iron plate is suppressed even in an environment where moisture, oxygen, and chlorine are present. I can do it.

Moreover, the concrete layer 4 receives the tsunami drifting material directly, so that the main body 100 provided on the inner side of the concrete layer 4 is less affected by the impact.

The concrete layer 4 is preferably unreinforced concrete. Thereby, it is possible to omit the bar arrangement work in the field construction, and the construction period can be shortened.

The door 5 is provided in the ground part F, and is welded to the housing 2 and the opening 8 of the hollow tube 3 as shown in FIG. The door 5 has a single or double door structure, and has both watertightness and impact resistance.

A method for building the shelter 1 will be described.

The main body 100 is created in a well-equipped factory. The manufacturing process is shown below.

After the plurality of hollow tubes 3 are placed on the side plate 21 and disposed at a predetermined position, the position is fixed by welding to the side plate 21. The support members 6U and 6L provided in the uppermost and lowermost hollow tubes 3U and 3L are inserted into recesses (not shown) formed in the upper and lower ends of the side plate 21, respectively.

The bottom plate 23 and the ceiling plate 22 are attached to the upper end portion and the lower end portion of the side plate 21, and the positions are fixed by welding to the side plate 21 and the supporting members 6U and 6L.

In the embodiment of the present invention, the ceiling plate 22 and the bottom plate 23 are provided outside the hollow tubes 3U and 3L. However, the hollow tubes 3U and 3L may be provided outside the ceiling plate 22 and the bottom plate 23. Further, the bottom plate 23 may be omitted.

An opening 8 is provided in the casing 2 and the hollow tube 3, and the door 5 is fixed to the opening 8 by welding as shown in FIG. The opening 8 may be formed in advance.

An injection hole (not shown) for injecting the mortar 3b into the hollow tube 3 and a confirmation hole (not shown) for removing the air filling the internal space 3a and confirming the filling state of the mortar 3b are formed. A plurality of confirmation holes are provided at predetermined intervals. The filling of the mortar 3b is confirmed by injecting the mortar 3b from the injection hole and discharging the mortar 3b from the confirmation hole. In addition, you may perform filling of the mortar 3b at a construction site.

The on-site construction process is shown below.

Drilling to a predetermined depth using manual excavation and a small excavator to form a hole H (see FIG. 4). Excavate carefully while confirming the stability of the slope. After excavation is completed, the bottom is rolled to correct the bottom unevenness and flatten. In addition, when spring water etc. are recognized, you may add the operation | work which spreads a crushed stone on the bottom part, and is equalized and rolled.

The foundation 10 is constructed by placing and curing concrete on the bottom. In consideration of facilitating the post-process, the foundation 10 is preferably finished with the upper surface kept horizontal as much as possible.

The main body 100 manufactured at the factory is brought into the installation site, suspended by a small crane, and temporarily fixed to the foundation 10 for installation.

A mold T is built only around the side plate 21 in a state where a predetermined distance from the side plate 21 is secured using a separator (not shown). Since the side plate 21 and the ceiling plate 22 function as an inner formwork at the time of placing concrete, it is not necessary to newly provide a formwork inside the formwork T. Moreover, since the ceiling board 22 is reinforced with the support material 6U, even if it receives the weight of the concrete at the time of placement directly, a deformation | transformation will be suppressed and predetermined | prescribed intensity | strength can be ensured. That is, it is not necessary to newly provide a support in the main body 100 in order to support the ceiling plate 22 that functions as a mold when placing concrete. In this way, support work for reinforcing the inner formwork and the ceiling plate 22 provided inside the main body 100 is not necessary, so that the cost can be reduced and the site construction period can be shortened.

Concrete is placed in a space formed between the formwork T and the main body 100. In addition, concrete is laid from the ceiling board 22 to a predetermined height. After the concrete is placed, the concrete placement surface on the ceiling board 22 is covered with a curing sheet and cured.

The formwork T is removed, and the space formed between the concrete layer 4 and the hole H is filled with soil or concrete. The soil used for backfilling may be generated at the construction site.

The present invention is applicable to an evacuation facility such as a shelter and has high industrial utility value.

1: Shelter 100: Main body 2: Housing 3, 3L, 3U: Hollow tube 3a: Internal space 3b: Mortar (filler)
4: Concrete layer 5: Doors 6L and 6U: Support material 8: Opening 10: Foundation 21: Side plate 22: Ceiling plate 23: Bottom plate A: Inner diameter C: Hollow tube inner diameter F: Above-ground part S: Underground part T: Formwork H: Hole

Claims (1)

Assembling the body,
Filling the interior space of the hollow tube with a filler;
Forming a hole;
Building a foundation at the bottom of the hole; installing the body on the foundation;
Building a formwork around the side plate of the body;
Placing and curing concrete in a space formed between the mold and the body; and
Removing the formwork and filling the space formed between the concrete layer and the hole with soil or concrete;
Equipped with a,
It said hollow tube is provided on the outer surface of the side plate of the main body, the semi-underground shelter construction method, wherein Rukoto embedded in the concrete layer.

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