TWI658193B - Construction method of semi-underground shelter - Google Patents

Abstract

A semi-underground refuge contains: a main body installed on a foundation and a concrete layer provided on the outer periphery of the main body. The main body includes: an iron box with a patio plate and a cylindrical side plate; a door provided above the box body; The inner diameter and diameter of the box are set within a fixed range; several circular hollow pipes are arranged on the outer surface of the side plate in the circumferential direction; the construction method of this semi-underground refuge is to make the body in the factory to form a hole. Build the foundation at the bottom of the cave, install the body on the foundation, build a formwork around the side slabs, pour and maintain the concrete, remove the formwork, and fill the gap with soil or concrete.

Description

Construction method of semi-underground shelter

The present invention is a semi-underground shelter in an area where disasters such as a tsunami are expected to occur.

The Great East Japan Earthquake in 2011 (2011), and the number of people killed and missing in the tsunami that followed, totaled more than 20,000 people, and it is estimated that the Great South China Sea Tsunami earthquake will occur in the future. For example, according to a message from the Cabinet Office, about 6,400 people are predicted to have died from the tsunami, about 1,800 people have died from the fire, and neighboring Shizuoka Prefecture has predicted that more than 95,000 people will die. In recent years, the concept of preventing earthquakes and tsunami has been increasing.

In order to prepare in advance for the Great South China Sea Tsunami that is expected to occur in the future, as a self-rescue measure, the demand for shelters in individual homes is also increasing. Various shelters have been proposed for shelters in the event of earthquakes and tsunamis, including fixed-to-foundation or floating-type.

A refuge fixed to a foundation is generally known as a refuge body composed of a composite structure composed of iron plates and concrete.

The invention disclosed in Patent Document 1 provides an underground shelter with excellent shock resistance and waterproofness. A pressure-resistant disc supported by several piles driving into the ground is provided with a high-strength An integrally formed box-shaped refuge formed by concrete and covered with an iron plate on the outer surface of the refuge body.

The aforementioned Patent Document 1 is Japanese Patent Application Laid-Open No. 2005-240452.

The problem to be solved by the invention: The underground refuge disclosed in Patent Document 1 has an iron plate covered with a concrete outer surface, which is in a state of being in constant contact with soil containing a large amount of water and oxygen, and is in an environment where corrosion is easily promoted. In order to prevent corrosion of the iron plate, it is necessary to apply waterproof coating on the outer surface of the iron plate, which is a major factor in increasing costs. In addition, when the concrete is poured into the gap between the iron plate and the formwork forming the patio, in order to support the formwork that directly bears the weight of the concrete, the formwork support must be erected from the ground, so the construction period becomes longer and the project becomes more complicated. At the same time, construction costs have also increased. The above-mentioned refuges with long construction period and high cost are difficult to be extended to ordinary families.

The object of the present invention is to provide a high-strength refuge with simple construction and reduced cost.

In order to solve the above problems, the present invention is a semi-underground refuge, which is characterized by including a body mounted on a foundation and a concrete layer provided on the outer periphery of the body. The body includes: iron made of a patio plate and a cylindrical side plate. The box body is a door provided on the upper part of the box body, and a plurality of ring-shaped hollow tubes provided on the outer surface of the side plate in a circumferential direction with respect to the inner diameter and diameter of the box body in a specified range.

With the above structure, a number of annular hollow pipes are provided on the outer surface of the side plate in the circumferential direction. Therefore, the side plates and several annular hollow pipes operate together to enhance the strength and rigidity of the box. Thereby, if a hollow tube is not provided in a side plate, the thickness of a side plate can be made thin. In other words, by using a low-cost hollow tube, the weight of a high-cost iron plate can be reduced. lower the cost.

The surface and voids of the soil particles in the ground contain water and oxygen, forming an environment that is very easy to promote the corrosion of iron plates. In addition, when the shelter is located near the coast, it is affected by the spray of seawater and promotes the corrosion of the iron plates above the ground. However, if the above-mentioned structure is adopted, a concrete layer is provided on the outer periphery of the steel body, so the surface of the iron plate forms a passive film due to the alkalinity of the concrete, and the iron plate can be prevented even in the presence of moisture and oxygen corrosion. Therefore, it is not necessary to perform treatment such as waterproof coating on the outer peripheral surface of the iron plate, which can reduce costs.

In addition, since the concrete layer having the above-mentioned structure is provided on the outer peripheral portion of the main body, the formwork required for pouring concrete may be provided only on the outer peripheral portion of the side plate. This makes on-site construction easy and shortens the construction period.

In the semi-underground refuge of the present invention, the space above the hollow pipe is set to be narrower than the space below the ground.

With the above-mentioned structure, the ground force is larger than the ground part, and the impact force of the tsunami drift pressure caused by the tsunami force, and the impact of the tsunami drifting object is reduced, and the space between the hollow pipes is reduced above the ground part. .

In the semi-underground refuge of the present invention, the uppermost and lowermost hollow pipes of the hollow pipes are provided with a plurality of supporting materials extending horizontally toward the center of the diameter, and the upper supporting materials are fixed to the patio board .

With the above-mentioned structure, the uppermost and lowermost hollow pipes in the hollow pipe are provided with a plurality of supporting materials extending horizontally toward the center of the diameter, and the supporting materials provided at the uppermost portion are fixed to the patio board. Therefore, the patio board and the The supporting material acts together to increase strength and rigidity. In addition, the effect of maintaining the cross-sectional shape of the lowermost part of the body is increased. This way, no special reinforcement is needed, you can directly on the patio board Concrete is poured, and it is easier to set the body on the foundation.

In the semi-underground refuge of the present invention, the hollow pipe is used to fill the internal space with a filling material.

When the inner space of the hollow tube is filled with air, the air filled in the inner space may be ejected toward the concrete layer due to flame heat and the like. At this time, the concrete layer will be damaged by the blasted air. In addition, when the air filled in the internal space is repeatedly compressed and expanded due to changes in the outside air temperature, the hollow tube is also repeatedly compressed and expanded at the same time. The concrete layer will deteriorate due to repeated compression and expansion. However, if the above-mentioned structure is adopted, the air existing in the internal space is discharged due to the filling of the filler, and therefore, the air is not ejected due to flame heat or the like. In addition, deterioration of concrete can be suppressed. In addition, the strength and rigidity of the hollow tube will increase by the combined action of the hollow tube and the filler.

In the semi-underground refuge according to the present invention, the cross section of the hollow tube is circular.

With the above structure, since the cross section of the hollow pipe is circular, the accuracy is improved, and the bending process of the hollow pipe is made easier.

The invention includes the following steps in the construction method of a semi-underground refuge: the step of assembling the body, the step of filling the filling material into the interior space of the hollow tube, the step of forming a hole, the step of building a foundation at the bottom of the hole, The step of installing on the foundation, the step of constructing the formwork around the side plate of the body, the curing step of pouring concrete into the space formed between the formwork and the body, and removing the formwork to fill the space formed between the concrete layer and the hole with soil or concrete step.

The above structure is adopted because it has the following steps: a step of forming a hole, a step of assembling the body, a step of filling a filling material into the inner space of the hollow tube, and a foundation of the foundation at the bottom of the hole Steps: the step of installing the body on the foundation, the step of constructing a formwork around the side plate of the body, the step of injecting concrete into the space formed by the gap between the formwork and the body, and removing the formwork to fill the space between the concrete layer and the hole with soil or concrete The steps of the formed space make construction on site easy and shorten the construction period.

1‧‧‧ Semi-underground refuge

100‧‧‧ Ontology

2‧‧‧ box

3, 3L, 3U‧‧‧ hollow tube

3a‧‧‧Internal space

3b‧ Plaster (filling material)

4‧‧‧ concrete layer

5‧‧‧ gate

6L, 6U‧‧‧ support material

8‧‧‧ opening

10‧‧‧ basic

21‧‧‧Side

22‧‧‧ Patio Board

23‧‧‧ floor

Inside diameter of A‧‧‧box

C‧‧‧Inner diameter of hollow tube

F‧‧‧ Above ground

S‧‧‧ underground

T‧‧‧Template

H‧‧‧hole

FIG. 1 is a cross-sectional view of a semi-underground shelter in an embodiment of the present invention.

Fig. 2 is a plan explanatory view showing a fixed structure of a semi-underground refuge door according to an embodiment of the present invention.

FIG. 3 is a side view and a cross-sectional view of the uppermost hollow tube and the lowermost hollow tube of the semi-underground refuge according to the embodiment of the present invention.

FIG. 4 is a front view of a body provided with a template state according to an embodiment of the present invention.

A semi-underground shelter 1 according to an embodiment of the present invention will be described. This semi-underground refuge 1 includes a foundation 10, a body 100 installed on the foundation 10, and a concrete layer 4 provided on the outer periphery of the body 100. This is explained in detail below.

As shown in FIG. 1, the foundation 10 is installed underground, and the main body 100 installed on the foundation 10 is composed of the upper part F and the lower part S. Dig the ground to a specified depth to form a hole H, and pour concrete into the bottom of the hole H to set the foundation 10 underground. The foundation 10 is preferably flat and horizontal, which can make the installation work of the main body 100 easier.

The main body 100 is resistant to earthquake forces, sea wave pressure caused by tsunami, and impact force caused by the collision of tsunami drifting objects, etc., and includes: an iron box 2, The door 5 is provided on the ground part F, and a plurality of annular hollow pipes are provided on the outer surface of the side plate 21 in the circumferential direction.

The box body 2 is composed of a bottom plate 23, a patio plate 22, and a cylindrical side plate 21. The inner diameter A of the box 2 is preferably 1.4m ~ 3m. In addition, the height of the ground part F is exemplified as 140 cm, and the height of the ground part S is exemplified as 140 cm. The construction of a small-scale semi-underground shelter made it possible to use a small construction machine and install it in a small area within a short period of time. As a result, it can promote the spread to ordinary households.

The plate thickness of the box 2 is preferably 2.0 mm to 6.0 mm, and is exemplified as 2.7 mm, 3 mm, and 4 mm. As described below, by appropriately disposing the hollow tube 3 and the supporting materials 6U and 6L, a strength equivalent to a plate thickness of 9 mm can be obtained.

A plurality of hollow tubes 3 are provided in a state of being fitted into a ring shape toward the circumferential direction of the outer surface of the side plate 21. The side plate 21 and the hollow pipe 3 are fixed by welding at an appropriate distance. Thereby, the side plate 21 and the hollow tube 3 operate in a combined force, and the strength and rigidity can be improved. The diameter B of the hollow pipe 3 can be bent into a ring shape with high accuracy, and the size can be fitted on the outer surface of the box 2, that is, the inner diameter A of the box 2 is 16/1000 The range to 35/1000 is ideal. As shown in FIG. 2, the inner diameter A of the box 2 is smaller than the inner diameter C of the ring formed by bending the hollow tube 3, and the gap is the thickness of the box 2.

The hollow pipe 3 is a carbon steel pipe for general structure. For example, it is preferably JIS G3444 STK500, a diameter of 48.6 mm, a thickness of 2.40 mm, and a hot-dip galvanizing specification (JIS H-8641, JIS H-9124). In addition, the cross section is not limited to a circular shape, and may be an angular shape.

The interval between the hollow pipes 3 above the ground F is set to the hollow pipes below the ground S The interval between 3 is narrow. The load acting on the semi-underground refuge 1 is the seismic force, the wave pressure of the tsunami, and the impact force of the tsunami drift. Seismic force is smaller in the ground and closer to the surface. Only above ground level F directly bears the wave pressure caused by the tsunami, and the wave pressure will not act on the ground level. The impact force caused by the tsunami drift is also the same. That is to say, the ground level F has a larger load than the ground level S. The above-ground part F having a larger load than the below-ground part S, in which the interval between the empty tubes 3 is set to be narrower than the interval between the underground tubes S, so that the thickness of the side plate 21 is kept thin. By appropriately setting the interval between the hollow pipes 3 as described above, the cost can be further reduced.

The inner space 3a of the hollow tube 3 is filled with stucco 3b (filling material) to form a state in which the air in the inner space 3a is exhausted. When the internal space 3a of the hollow pipe 3 is filled with air, the filled air may be ejected toward the concrete layer 4 due to flame heat or the like. At this time, the concrete layer 4 may be damaged due to the emitted air. In addition, 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 is also repeatedly compressed and expanded simultaneously. As a result, the concrete layer 4 is deteriorated by repeated compression and expansion. Therefore, the concrete layer 4 is filled with the plaster 3b because the inner space 3a of the hollow tube 3 is filled, so that damage caused by the ejected air can be prevented, and degradation can be suppressed at the same time. In addition, the combined action of the hollow tube 3 and the plaster 3b increases the strength and rigidity of the hollow tube 3. In addition, although mortar is used as the filler in the embodiment of the present invention, concrete slurry may be used.

The support material 6U is used to reinforce the patio board 22. As shown in FIG. 3, the six support materials 6U are evenly arranged and fixed in the circumferential direction of the uppermost hollow tube 3U, and at the same time, extend horizontally toward the center of the diameter, and in the middle The central portions of the empty tubes 3U are fixed to each other. In addition, it is welded and fixed to the patio board 22 at appropriate intervals. That is, the patio board 22 operates in conjunction with the supporting material 6U to obtain a predetermined strength and rigidity. Thereby, it is possible to suppress the Deformation can be directly poured into the patio slab 22 without special reinforcement.

The supporting material 6L is used to suppress the deformation of the main body 100 and make it easier to mount the main body 100 on the foundation 10. Since it is almost the same as the structure supporting the 6U, the description is omitted.

The supporting materials 6U and 6L are ideal for general-purpose steel.

The concrete layer 4 is used to protect the main body 100 from being damaged by flame heat, a corrosive environment, and a tsunami drift, and is provided on the outer periphery of the main body 100. The thickness of the concrete layer 4 is preferably 15 cm to 30 cm.

When the concrete layer 4 is not provided on the outer peripheral portion of the main body 100, the rigidity of iron plates and the like constituting the main body 100 will be reduced and severely deformed when the main body 100 exceeds the specified temperature due to flame heat. If the concrete layer 4 is provided, the temperature rise of the box body 2 can be suppressed, and the main body 100 can be fixed by the concrete layer 4 at the same time. As a result, deformation of the main body 100 can be suppressed.

Because the surface of the soil particles and the voids in the ground contain water and oxygen, an environment that easily promotes corrosion of iron plates is formed. In addition, when a semi-underground refuge 1 is installed near the coast, it is affected by the spray of seawater and promotes the corrosion of iron plates. However, if a concrete layer 4 is provided on the outer periphery and the alkali of the concrete layer 4 is penetrated, a passive state film is formed on the surface of the iron plate, and the corrosion of the iron plate can be suppressed even in the environment where moisture, oxygen and chlorine are present.

In addition, because the concrete layer 4 directly receives the tsunami drift, the body 100 provided on the inner side of the concrete layer 4 will be less affected by the impact.

The concrete layer 4 is ideally made of unreinforced concrete, so that the reinforcement work on site can be omitted, and the construction period can be shortened.

The door 5 is installed on the ground floor F, and is welded to the box 2 and the hollow as shown in FIG. 2 The opening 8 of the tube 3. The door 5 has a structure of one or two doors, and has both water tightness and impact resistance.

The construction method of the semi-underground shelter 1 will be described.

The body 100 is manufactured in a fully equipped factory. The production process is shown below.

Several hollow tubes 3 are externally embedded in the side plate 21 and arranged at a fixed position, and then welded 21 to fix the position. In addition, the supporting materials 6U and 6L provided in the uppermost and lowermost hollow pipes 3U and 3L are inserted into recessed portions (not shown) formed at the upper and lower end portions of the side plate 21.

The bottom plate 23 and the patio plate 22 are installed on the upper and lower ends of the side plate 21, and welded to the side plate 21 and the supporting materials 6U and 6L to fix the position.

Moreover, in the embodiment of the present invention, the patio plates 22 and the bottom plate 23 are provided outside the hollow tubes 3U and 3L, but the hollow tubes 3U and 3L may be provided outside the patio plates 22 and the bottom plate 23. The base plate 23 may be omitted.

An opening 8 is provided in the box body 2 and the hollow pipe 3, and as shown in FIG. 2, the door 5 is welded to the opening 8 to be fixed. The opening 8 may be formed in advance.

Formed in the hollow tube 3: an injection hole (not shown) for injecting the plaster 3b, an air hole for extracting the air filled in the internal space 3a, and a confirmation hole (not shown) for confirming the filling condition of the plaster 3b . Confirm that there are several holes at a fixed interval. The plaster 3b is injected through the injection hole, and the plaster 3b is discharged through the confirmation hole to confirm the filling of the plaster 3b. In addition, the filling of the plaster 3b may be performed at the construction site.

The site construction process is shown below.

Digging by manpower or using a small excavator to a specified depth to form a hole H (see Figure 4). While checking whether the slope is stable, excavate carefully. After the excavation is completed, the bottom is compacted to flatten the bottom surface for flattening. In addition, when it is confirmed that water gushing occurs, it is possible to lay crushed stones on the bottom and perform additional compaction.

The foundation 10 is constructed by pouring and curing concrete at the bottom. In order to consider that the subsequent projects are easy to carry out, it is best to ensure that the foundation 10 is horizontal as far as possible.

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

Using a separator (not shown), a template T is built around the side plate 21 while ensuring a specified distance from the side plate 21. The function of the side plate 21 and the patio plate 22 is to be used as the inner formwork when pouring concrete, so there is no need to set a new formwork inside the formwork T. In addition, the patio slab 22 is reinforced by the 6U support material, so that even if it directly bears the weight of the concrete, the deformation can be suppressed, and the specified strength can be ensured. That is to say, when the concrete is poured, the patio board 22 functioning as a formwork is supported, so there is no need to provide a formwork inside the body 100. In this way, the inner formwork is not required, and the formwork support provided in the body 100 to reinforce the patio board 22 can reduce costs and shorten the construction period on site.

Concrete is poured into the space formed between the formwork T and the body 100. The concrete is poured from the patio slab 22 to a predetermined height. After the concrete is poured, the concrete pouring surface on the patio board 22 is covered by a curing step for curing.

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 can also be the soil produced at the construction site.

The invention can be applied to evacuation facilities such as refuges, and the industrial utilization price is quite high.

Claims (1)

A construction method for a semi-underground refuge, which is characterized by having the following steps: a step of assembling the body; a step of filling a filling material into the inner space of the hollow tube; a step of forming a hole; a step of constructing a foundation at the bottom of the hole; The step of installing the aforementioned body on the aforementioned foundation; the step of constructing a form around the side plate of the aforementioned body; the step of injecting concrete into the void formed by the gap between the aforementioned form and the aforementioned body; and removing the aforementioned form to fill the concrete layer with soil or concrete And the space formed between the aforementioned holes.