JP7119563B2 - building - Google Patents

Description

The present invention relates to buildings.

“Lightning protection for buildings” (JIS A 4201-2003), which aims to protect buildings and human lives from lightning, includes “external lightning protection systems” for buildings and facilities and equipment inside buildings. It is divided into “internal lightning protection system” and “internal lightning protection system”, and lightning protection standards are indicated for each.

In the external lightning protection system, the lightning-termination part and the down conductor are electrically connected so that the lightning current is discharged to the earth (ground) through the ground electrode.

In addition, in internal lightning protection systems, the part to be protected is completely insulated from the building frame (see, for example, Patent Document 1), or the generation of potential difference inside the building is eliminated, effectively shunting the intruding lightning current. Equipotential bonding is required to allow For equipotential bonding, horizontal ring conductors should be provided close to the ground surface and at maximum vertical intervals of 20 m. For example, in the case of reinforced concrete buildings, slab bars can be used as horizontal ring conductors.

JP 2005-273328 A

However, in the case of a wooden building, the floor material (wood) does not have metal objects (conductors) such as reinforcing bars inside, unlike the floor made of reinforced concrete. For this reason, it was difficult to equipotentialize wooden buildings.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and an object of the present invention is to achieve equipotential bonding in a wooden building.

In order to achieve such an object, the building of the present invention is a wooden building,
a wooden structural floor;
an upper floor material provided above the structural floor in the vertical direction;
a peripheral conductor having a cross-sectional area of 100 mm or more, which is provided along the periphery of the building and is electrically connected to the ground;
a horizontal conductor disposed between the structural floor and the upper floor material and electrically connected to the perimeter conductor;
with
The structural floor is composed of a plurality of structural floor units divided by the division part,
adjacent structural floor units are spaced apart from each other in the dividing section;
The horizontal conductor is composed of a plurality of conductor units divided by the dividing portion,
In the divided portion, the adjacent conductor units are separated from each other,
The adjacent conductor units are electrically connected by a bridging conductor that straddles the divided portion .
Also, in a wooden building,
a wooden structural floor;
an upper floor material provided above the structural floor in the vertical direction;
a peripheral conductor having a cross-sectional area of 100 mm2 or more, which is provided along the periphery of the building and is electrically connected to the ground;
a horizontal conductor disposed between the structural floor and the upper floor material and electrically connected to the perimeter conductor;
a lightning rod provided at the top of the building;
a lead-down wire provided between the lightning rod and the ground;
with
The peripheral conductor is electrically connected to the down conductor.
According to such a building, equipotential bonding can be achieved in a wooden building.

In such a building, the structural floor is composed of a plurality of structural floor units divided by the dividing portion, and the horizontal conductor is composed of a plurality of conductor units divided by the dividing portion, It is desirable that the adjacent conductor units are electrically connected by a bridging conductor that straddles the divided portion.
According to such a building, it is possible to easily construct the floor.

In such a building, it is desirable that a plurality of the down conductors are provided around the building, and the peripheral conductor is electrically connected to the plurality of down conductors.
According to such a building, the current flowing through the down conductor can be distributed.

In such a building, the horizontal conductors are preferably structural steel plates.
According to such a building, the structural floor can be made thinner.

According to the present invention, equipotential bonding can be achieved in a wooden building.

It is the schematic of the building 1 of this embodiment. 4 is a cross-sectional view showing the configuration of a floor 40; FIG. FIG. 3 is a diagram showing an example of a current path during a lightning strike in the building 1;

An embodiment of the present invention will be described below with reference to the drawings.

===Embodiment===
<<Regarding the configuration of Building 1>>
FIG. 1 is a schematic diagram of a building 1 of this embodiment. The building 1 of this embodiment is a wooden building having a rectangular planar shape, and includes a lightning-termination section 10 , a down conductor 20 , a pillar 30 , a floor 40 , and an outer conductor 50 .

The lightning receiver 10 is a lightning rod and is provided at the top of the building 1 . In this embodiment, the lightning receivers 10 are provided at the four corners (corners) of the building 1, respectively.

The down conductor 20 is provided along the pillar 30 (in the vertical direction) as a current path from the lightning-termination section 10 to the ground G. The down conductor 20 is provided (in a straight line) so that the length of the current path due to lightning strikes is minimized. Also, the down conductor 20 is made of a material with low resistance, such as iron, copper, or aluminum, so that current can flow efficiently. In this embodiment, down conductors 20 are provided for each of the four lightning receivers 10 . These four pull-down conductors 20 are electrically connected via peripheral conductors 50 and the like, which will be described later.

The pillar 30 is a structure that supports a vertical load such as a beam (not shown) or a floor 40, and is erected along the vertical direction. The pillars 30 of this embodiment are wooden members, and are provided at the four corners of the building 1, respectively.

The floor 40 is a horizontal and flat plate-like structure located on the bottom surface of each floor in the building 1 . Note that FIG. 1 specifically shows only the floor 40 on the third floor, but the floors 40 on each floor have the same configuration (the same applies to the outer conductor 50 and the like). In addition, in FIG. 1 , the upper portion (upper floor material 32 described later) of a part (for two units) of the floor 40 is shown transparently. The interval (vertical interval) between floors 40 on adjacent floors is 20 m or less. Details of the configuration of the floor 40 will be described later.

The outer conductor 50 is provided along the outer circumference of the building 1 so as to surround the outside of the floor 40 . The outer conductor 50 of the present embodiment is made of steel having a cross-sectional area of 100 mm ² or more. In addition, the outer conductor 50 is electrically connected to the down conductor 20 by the conductor D1 (in other words, electrically connected to the ground G). In addition, the outer conductor 50 is electrically connected to a horizontal conductor 43 (horizontal conductor unit 43A) of the floor 40, which will be described later, by a conductor D2.

Although not shown, the foundation of the building 1 of this embodiment is made of reinforced concrete (RC). The current flowing through the down conductor 20 flows from the reinforcing bars to the ground G through the concrete. Moreover, it is not limited to this, and for example, a plate-shaped or rod-shaped ground electrode may be separately provided on the ground G and connected to the pull-down conductor 20 .

<<Regarding the configuration of the floor 40>>
FIG. 2 is a cross-sectional view showing the configuration of the floor 40. As shown in FIG. The configuration of the floor 40 will be described below with reference to FIG. 1 as well.

The floor 40 of this embodiment has a rectangular planar shape. Further, the floor 40, as shown in FIG. 2, has a double structure floor (structural floor 41 and upper floor material 42) and a horizontal conductor 43 arranged therebetween.

The structural floor 41 is a wooden structure and is provided below the floor 40 .

The upper floor material 42 is provided vertically above the structural floor 41 (above the floor 40). The upper floor material 42 of this embodiment is a wooden plate-like member. By providing the upper floor material 42, for example, a nail can be driven into the surface of the floor 40. - 特許庁

A horizontal conductor 43 is sandwiched between the structural floor 41 and the upper flooring 42 . As shown in FIG. 1, the horizontal conductor 43 of this embodiment is made of a metal mesh (wire mesh).

As shown in FIG. 2, the floor 40 of the present embodiment is constructed by arranging a plurality of floor units 40A divided by a dividing portion 40B vertically and horizontally. Each floor unit 40A comprises a structural floor unit 41A, an upper floor material unit 42A, and a horizontal conductor unit 43A (corresponding to a conductor unit). That is, the structural floor 41 is composed of a plurality of structural floor units 41A divided by the dividing portion 40B, and the horizontal conductor 43 is composed of a plurality of horizontal conductor units 43A divided by the dividing portion 40B. The upper floor material 42 is composed of a plurality of upper floor material units 43A divided by the dividing portion 40B. Further, the horizontal conductor units 43A of the adjacent flooring units 40A are electrically connected by a conductor D3 (corresponding to a straddle conductor) straddling the split portion 40B. By configuring the floor 40 with a plurality of floor units 40A in this way, construction can be easily performed even if the floor 40 has a large area.

<<About equipotential bonding>>
Equipotential bonding refers to the connection of lightning protection systems, metal structures, metal workpieces, off-grid conductive parts, and power and communication equipment in the protected object with bonding conductors or surge protection devices. It is to equipotentialize. It also refers to measures to protect electronic equipment and people inside buildings from lightning currents.

Equipotential bonding should be provided near the surface of the earth or at points on the surface of the earth at vertical intervals of 20 m or less. More specifically, the down conductor at this point should be provided with a horizontal ring conductor. For example, in the case of a reinforced concrete building, a reinforcing bar (slab bar) or the like provided inside the floor can be used as a horizontal annular conductor. However, in the case of wooden structures, there are no metal objects (conductors) such as reinforcing bars inside the floor, so potential equalization has not been achieved.

Therefore, in the building 1 of the present embodiment, the floor 40 of each floor has a double structure, a horizontal conductor 43 is provided between them, and the horizontal conductor 43 is electrically connected to the outer conductor 50 to form a horizontal annular conductor. is doing. As a result, equipotentialization (equipotential bonding) can be achieved in the wooden building 1, and a lightning protection system conforming to JIS A 4201-2003 can be constructed. By setting the cross-sectional area of the outer conductor 50 electrically connected to the down conductor 20 to 100 mm ² or more, the temperature rise of the outer conductor 50 when all or most of the lightning current flows can be suppressed. , There is no need to separate from combustible materials (woody members). Also, since a large current does not flow through the horizontal conductor 43 arranged in the floor 40, even if the horizontal conductor 43 is in contact with combustible materials (the structural floor 41 and the upper floor material 42), it does not reach a temperature at which ignition occurs.

FIG. 3 is a diagram showing an example of current paths in the building 1 when lightning strikes.

When lightning strikes the lightning-termination section 10 of the building 1, the current (lightning current) due to the lightning strike flows through the down conductor 20 connected to the lightning-termination section 10 and the other down conductors 20 via the outer conductor 50. flow. This allows the current to be distributed. Then, a current flows from each down conductor 20 to the ground G. Further, current also flows through the horizontal conductors 43 (the plurality of horizontal conductor units 43A) of the floor 40 via the outer conductor 50 and the like. Thereby, the potential difference in the floor 40 of the building 1 can be eliminated, and local voltage rise can be suppressed. Therefore, it is possible to protect equipment and the like arranged in the building 1 (internal lightning protection). Further, as described above, the cross-sectional area of the peripheral conductor 50 is set to 100 mm ² or more, so even if most of the lightning current flows through the peripheral conductor 50, the temperature rise can be suppressed.

As described above, the building 1 of the present embodiment is a wooden building, and the floor 40 and the floor 40, which are provided along the outer periphery of the building 1 and electrically connected to the ground G, have a cross-sectional area of 100 mm ² The peripheral conductor 50 described above is provided. The floor 40 is arranged between a structural floor 41 made of wood, an upper floor material 42 provided vertically above the structural floor 41 , and between the structural floor 41 and the upper floor material 42 . and a horizontal conductor 43 electrically connected to the .

As a result, equipotential bonding can be achieved in the wooden building 1, and a lightning protection system conforming to JIS A 4201-2003 can be constructed.

===Other Embodiments===
The above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to limit and interpret the present invention. The present invention can be modified and improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof. In particular, even the embodiments described below are included in the invention.

<About Building 1>
In the above-described embodiment, the building 1 has a rectangular planar shape, but it is not limited to this and may have any shape. Moreover, although the building 1 was a three-story building in the above-described embodiment, it is not limited to this. For example, it may be a two-story building, or it may be a four-story building or more.

<Regarding lightning receiver 10>
In the above-described embodiment, the lightning receivers 10 (lightning rods) are provided at the four corners of the top of the building 1, but the present invention is not limited to this. For example, the lightning receiver 10 may be provided in the center of the plane of the top of the building 1 and connected to four down conductors 20 . Further, although the lightning receiver 10 is a lightning rod in the above embodiment, it is not limited to this. For example, it may be a horizontal conductor, a mesh conductor, or a combination thereof.

<Regarding the pull-down conductor 20>
Although the down conductors 20 were provided at the four corners of the building 1 in the above-described embodiment, the present invention is not limited to this. For example, the down conductor 20 may be provided at the central position of each side of the building 1 .

<About the floor 40>
In the above-described embodiment, the floors 40 on all floors of the building 1 have the same configuration, but this is not the only option. In other words, equipotential bonding may be applied to the floors 40 of specific floors with a vertical interval of 20 m or less, and the other floors 40 may not be equipotentially bonded (horizontal conductors 43 may not be provided). Also, the floor 40 in this case may not have a double structure.

In addition, in the above-described embodiment, the horizontal conductor 43 is a mesh-like metal, but it is not limited to this, and any member having conductivity may be used. For example, it may be a structural steel plate, a carbon sheet, a stainless steel or aluminum tape, or the like. If a structural steel plate is used as the horizontal conductor 43, the structural floor 41 can be made thin. This allows the floor 40 to be thin. Using a mesh-shaped metal as the horizontal conductor 43 as in the above-described embodiment can reduce the weight as compared with the case of using a structural steel plate.

Further, in the above-described embodiment, the upper floor material 42 is a wooden plate-like member, but it is not limited to this. For example, it may be of a removable panel type (such as a board).

Further, in the above-described embodiment, the floor 40 is divided into a plurality of floor units 40A at the dividing portion 40B, but the floor units 40A may not be divided (they may be integrated). Alternatively, only the upper floor material 42 may be integral.

1 Building 10 Lightning Termination 20 Down Conductor 30 Column 40 Floor 40A Floor Unit 40B Division 41 Structural Floor 41A Structural Floor Unit 42 Upper Floor Material 42A Upper Floor Material Unit 43 Horizontal Conductor 43A Horizontal Conductor Unit (Conductor Unit)
50 Peripheral conductor D1 Conductor D2 Conductor D3 Conductor (straddling conductor)
G Ground

Claims (5)

a wooden building,
a wooden structural floor;
an upper floor material provided above the structural floor in the vertical direction;
a peripheral conductor having a cross-sectional area of 100 mm or more, which is provided along the periphery of the building and is electrically connected to the ground;
a horizontal conductor disposed between the structural floor and the upper floor material and electrically connected to the perimeter conductor;
with
The structural floor is composed of a plurality of structural floor units divided by the division part,
adjacent structural floor units are spaced apart from each other in the dividing section;
The horizontal conductor is composed of a plurality of conductor units divided by the dividing portion,
In the divided portion, the adjacent conductor units are separated from each other,
The adjacent conductor units are electrically connected by a bridging conductor that straddles the divided portion.
A building characterized by a wooden building,
a wooden structural floor;
an upper floor material provided above the structural floor in the vertical direction;
a peripheral conductor having a cross-sectional area of 100 mm or more, which is provided along the periphery of the building and is electrically connected to the ground;
a horizontal conductor disposed between the structural floor and the upper floor material and electrically connected to the perimeter conductor;
a lightning rod provided at the top of the building;
a lead-down wire provided between the lightning rod and the ground;
with
the peripheral conductor is electrically connected to the down conductor;
A building characterized by A building according to claim 2,
The structural floor is composed of a plurality of structural floor units divided by the division part,
The horizontal conductor is composed of a plurality of conductor units divided by the dividing portion,
The adjacent conductor units are electrically connected by a bridging conductor that straddles the divided portion.
A building characterized by A building according to claim 3,
A plurality of the down conductors are provided around the building,
The outer conductor is electrically connected to a plurality of the down conductors,
A building characterized by The building according to any one of claims 1 to 4,
wherein the horizontal conductor is a structural steel plate;
A building characterized by

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