JP7516581B2 - Fireproof construction - Google Patents

Description

The present invention relates to a fire-resistant structure.

Conventionally, the use of reinforced gypsum boards has been known as a method for making the walls, floors, ceilings, etc. of wooden buildings fire-resistant. Reinforced gypsum boards consume thermal energy by converting the crystallized water contained in them into water vapor due to the heat of a fire, making it possible to contain a fire for a certain period of time. Therefore, by increasing the thickness of the gypsum board, it is possible to obtain high fire resistance.

As a fireproof structure for wooden buildings using reinforced gypsum boards, for example, a technology is known in which an aluminum sheet of a certain thickness is sandwiched between two layers of gypsum boards, and the radiant insulation function of this aluminum sheet reduces the heat transmitted to the underlying gypsum boards and wooden substrate, making it possible to reduce the thickness of the fireproof coating layer made of gypsum boards (see Patent Documents 1 and 2).

Patent No. 3673516 JP 2007-39915 A

In the fire-resistant structures described in Patent Documents 1 and 2, the total thickness of the gypsum board required to meet the standards for a one-hour fire-resistant structure is 36 mm or more. Since gypsum board contains a lot of water and is a very heavy material, there is currently a demand to make gypsum board even thinner while maintaining fire resistance from the standpoint of improving workability, reducing the weight of buildings, expanding living space, etc.

The object of the present invention is therefore to provide a fire-resistant structure in which the gypsum board is thin and lightweight, and which has excellent fire resistance and ease of construction.

In other words, the present invention is as follows.

[1] A fire-resistant structure characterized by having non-combustible material, panel insulation, and gypsum board laminated in that order.

[2] Fire-resistant structure of [1] used in buildings containing wood materials.

[3] A fire-resistant structure according to [2], in which at least a portion of the gypsum board is laminated with the wood material and used in a building that includes wood material.

[4] A fire-resistant structure according to [2] or [3], in which the wood material is a material that constitutes the underfloor of a building.

[5] A fire-resistant structure according to any of [1] to [4], using the above gypsum board with a total thickness of 35 mm or less, which satisfies the two-hour fire resistance standard in a fire resistance performance test conducted in accordance with ISO 834.

[6] A fireproof structure according to any one of [1] to [5], wherein the non-combustible material is a calcium silicate board.

[7] A fire-resistant structure according to any one of [1] to [6], wherein the panel insulation material is a phenolic resin foam board.

[8] A fire-resistant structure according to any one of [1] to [7], in which the non-combustible material, the panel insulation material, the gypsum board, and the wood material are laminated in this order.

[9] A fireproof structure according to [8], in which the wood material is a material that constitutes the wood material structural part of a building.

[10] A fireproof structure according to [8] or [9], in which the wood material is the material that constitutes the underfloor.

The fire-resistant structure of the present invention has the above-mentioned configuration, making it lightweight and excellent in fire resistance and workability.

FIG. 1 is a schematic diagram (cross-sectional view) showing an example of a fireproof structure according to the present embodiment. FIG. 2 is a schematic diagram (cross-sectional view) showing a conventional fire-resistant structure. FIG. 3 is a schematic diagram (cross-sectional view) showing the laminate of Comparative Example 1. FIG. 4 is a schematic diagram showing an example in which the fireproof structure of this embodiment is provided on a floor and under the floor. FIG. 5 is a photograph of the surface of the wood material of Example 1 after the fire resistance test. FIG. 6 is a photograph of the surface of the wood material of Comparative Example 1 after the fire resistance performance test.

[Fireproof structure]
The fire-resistant structure of the present invention has a noncombustible material, a panel insulation material, and a gypsum board laminated in this order with the respective components in contact with each other.

The present inventors have investigated conventional fireproof structures for wooden buildings and have found the following problems.
In a conventional fireproof structure (FIG. 2) in which a laminate of reinforced gypsum board (a) 6/aluminum sheet 7/reinforced gypsum board (b) 8 is provided on a wooden material 5, the heat of a fire is quickly transferred to the reinforced gypsum board (a) 6, and the crystallized water in the reinforced gypsum board (a) 6 becomes water vapor. Since the aluminum sheet 7 does not allow water vapor to pass through, the generated water vapor moves to the fire source side and evaporates quickly, and the reinforced gypsum board (a) releases the crystallized water in a short time. Although the aluminum sheet 7 blocks radiant heat, it has high thermal conductivity, so that conductive heat is easily transferred to the reinforced gypsum board (b) 8. Therefore, the reinforced gypsum board (b) 8 is easily heated, and the crystallized water in the reinforced gypsum board (b) 8 also easily evaporates.
In order to solve the above problems, the present inventors have conducted extensive research into the materials used and the layer structure of the fire-resistant structure.

The fire-resistant structure 1 of the present invention has a structure of a noncombustible material 2/a panel insulation material 3/a gypsum board 4. Fig. 1 shows an example of the fire-resistant structure of this embodiment, in which the gypsum board 4 is laminated on a wooden material 5 in a state where the wooden material 5 is in contact with the gypsum board 4.
By providing the non-combustible material 2 on the surface side, it is difficult to burn even if a fire occurs on the side of the non-combustible material 2. In addition, if a material with heat insulating and heat reflective properties is used for the non-combustible material 2, the heat conduction to the gypsum board 4 can be further suppressed.
By providing the panel insulation material 3 under the non-combustible material 2, the heat transmitted through the non-combustible material 2 is blocked by the panel insulation material 3 and is less likely to be transmitted to the gypsum board 4. Furthermore, if a material that does not melt but is carbonized by heat is used as the panel insulation material 3, the fire does not directly come into contact with the gypsum board, so heating of the gypsum board 4 after the panel insulation material is carbonized can be suppressed.
By providing the gypsum board 4 under the noncombustible material 2/panel insulation material 3, conductive heat is less likely to be transmitted to the gypsum board 4, and the time period during which the crystal water in the gypsum board 4 decomposes into water can be delayed. Furthermore, when a material with a low moisture permeability coefficient is used as the panel insulation material 3, water vapor generated in the gypsum board 4 is less likely to move toward the source of the fire and is more likely to remain in the gypsum board 4 or the wood material 5, making it even more difficult for the gypsum board 4 to heat up.
The inventors have found that the layer structure allows the thickness of the gypsum board to be reduced while providing excellent fire resistance. The same effect as above can be obtained even if other layers are inserted between the components as long as the effect of the present invention is not impaired.

(Non-combustible material)
The non-combustible material is preferably one that has low thermal conductivity and is non-flammable.
The thermal conductivity of the noncombustible material is preferably 0.03 to 0.24 W·m ⁻¹ ·K ⁻¹ , and more preferably 0.05 to 0.14 W·m ⁻¹ ·K ⁻¹ . In this specification, the thermal conductivity refers to a value measured in accordance with JIS A1412.

Examples of the non-combustible materials include ALC panels (lightweight aerated concrete cured with high-temperature and high-pressure steam), calcium silicate boards, concrete, bricks, roof tiles, ceramic tiles, fiber-reinforced cement boards, steel plates, aluminum plates, glass plates, mortar boards, fireproof wood, etc. Among these, calcium silicate boards and aluminum plates are preferred from the viewpoint of thermal conductivity, and calcium silicate boards are more preferred.
The above-mentioned non-combustible materials may be used alone or in a combination of the same type and/or a plurality of types.

(Panel insulation)
The panel insulation material is preferably one that is heat resistant and carbonizable. Examples of the panel insulation material include resin foam boards such as phenol foam and styrene foam; plate-shaped fibers such as rock wool and glass wool; and the like. Among them, from the viewpoints of light weight and thermal conductivity, phenol foam and rock wool are preferred, and phenol foam (phenol resin foam board) is more preferred.
The panel insulation material may be used alone or in a combination of the same type and/or a plurality of types.

The thermal conductivity of the panel insulation is preferably 0.018 to 0.050 W·m ^{-1·K-1, more preferably 0.018 to 0.035 W·m-1 ·} K ^{-1 ,} from the viewpoint of obtaining even better long-term fire resistance by making it difficult for heat transmitted to the panel insulation to be transmitted to the gypsum board.

The panel insulation material is preferably impermeable to water vapor, since water vapor generated in the gypsum board is likely to remain in the gypsum board or the wood material without penetrating to the non-combustible material side where the fire source is located. Specifically, the moisture permeability coefficient of the panel insulation material is preferably 30 to 290 ng/( ^m2 ·s·Pa), and more preferably 30 to 60 ng/( ^m2 ·s·Pa).
The moisture permeability coefficient is a value measured in accordance with JIS A1324 at a thickness of 25 mm.

From the viewpoint of light weight, the density of the panel insulation material is preferably 10 to 60 kg/ ^m3 , and more preferably 10 to 30 kg/ ^m3 .
The density refers to a value calculated from the mass and apparent volume of the insulating material measured in accordance with JIS K7222.

(Gypsum board)
The gypsum board is not particularly limited as long as it is a board mainly composed of gypsum, and examples thereof include JIS A6901 gypsum board (GB-R), sheathing gypsum board (GB-S), reinforced gypsum board (GB-F, GB-F(V)), gypsum lath board (GB-L), decorative gypsum board (GB-D), non-combustible laminated gypsum board (GB-NC), ordinary hard gypsum board (GB-R-H), sheathing hard gypsum board (GB-S-H), decorative hard gypsum board (GB-D-H), structural gypsum board (GB-St-A, GB-St-B), moisture absorbing and releasing gypsum board, etc. Among them, reinforced gypsum board is preferable from the viewpoint of fire resistance.
The gypsum board may be used alone or in a combination of the same type and/or a plurality of types.

(Wood materials)
The wood material is not particularly limited, and examples thereof include plywood, CLT (Cross Laminated Timber), LVL (Laminated Veneer Lumber), etc. The type of wood is not particularly limited, and may be either a coniferous tree or a broad-leaved tree.
The above-mentioned wood material may be subjected to a treatment such as an antiseptic treatment, as long as the effect of the present invention is not impaired.
The above wood materials may be used alone or in combination of the same and/or multiple types.

The wood material may be a wood material structural part of a building, such as a floor, wall, underfloor (ceiling), roof, pillar, beam, frame, or part thereof of a wooden building; wood material used in a steel frame structure, RC structure, or SRC structure; etc.
Among these, under-floor construction is preferable, as it requires skilled workers to work upwards, making construction difficult.

(Production method)
The method for manufacturing the fireproof structure of this embodiment is not particularly limited, but may be, for example, a method in which the noncombustible material, panel insulation material, and gypsum board are laminated and fixed with screws, staples, nails, etc. Fixing may be performed by fixing only two adjacent members, or by fixing three or more members together. In the fireproof structure of this embodiment, the wood material and the gypsum board may be fixed by the above method.
Gypsum board is made of a material that contains a lot of crystal water, and is a very heavy material. Therefore, when installing it under a floor (ceiling), for example, it is necessary to fix it by driving in a large number of screws while it is lifted up, and improvements have been required from the viewpoint of workability. According to the fire-resistant structure of the present invention, the gypsum board can be made thin and light, so workability is significantly improved.

The fireproof structure of this embodiment may be manufactured on-site, or may be manufactured elsewhere, such as in a factory, and then transported to the location where it will be used.

(Physical Properties)
In the fire-resistant structure of this embodiment, the total thickness of the noncombustible material, the panel insulation material, and the gypsum board is preferably 50 to 150 mm, and more preferably 50 to 100 mm.
The thickness of the non-combustible material is preferably 12 to 70 mm, and more preferably 15 to 25 mm. When a plurality of non-combustible materials are laminated, the thickness of the non-combustible material refers to the total thickness of all the non-combustible materials.
The thickness of the panel insulation is preferably 20 to 100 mm, and more preferably 20 to 50 mm. When a plurality of panels of insulation are laminated, the thickness of the panel insulation refers to the total thickness of all the panels of insulation.
The thickness of the gypsum board is preferably less than 36 mm, more preferably 35 mm or less, even more preferably 30 mm or less, even more preferably 9.5 to 25 mm, and particularly preferably 15 to 25 mm. When a plurality of gypsum boards are laminated, the thickness of the gypsum board refers to the total thickness of all the gypsum boards.

In the fire-resistant structure of this embodiment, the ratio of the thickness (mm) of the gypsum board to the thickness (mm) of the panel insulation (thickness of the gypsum board/thickness of the panel insulation) is preferably 0.3 to 1.6, more preferably 0.4 to 1.0, and even more preferably 0.5 to 0.7, from the standpoint of ease of construction and economic efficiency.

In the evaluation of the fire resistance performance test conforming to ISO834, the fire resistant structure of this embodiment preferably meets the standard for a one-hour fire resistant structure using gypsum boards with a total thickness of 35 mm or less (more preferably 25 mm or less), and more preferably meets the standard for a two-hour fire resistant structure. In particular, it is preferable to meet the standard for a one-hour fire resistant structure using a panel insulation material with a total thickness of 20 to 50 mm and gypsum boards with a total thickness of 25 mm or less, and more preferably meets the standard for a two-hour fire resistant structure.

It is preferable that the fire-resistant structure of this embodiment meets the standards for a one-hour fire-resistant structure when evaluated in a fire resistance test conforming to ISO 834. It is even more preferable that the fire-resistant structure of this embodiment meets the standards for a two-hour fire-resistant structure when evaluated in a fire resistance test conforming to ISO 834.

The fire-resistant structure of this embodiment can be used in any structure, but is preferably used in buildings containing wood materials where the required performance is to prevent wood from carbonizing within a specified period of time, and it is even more preferable to use a portion of the gypsum board and the wood material laminated together in a building containing wood materials.
The above-mentioned building is not limited as long as it contains wood materials, and examples thereof include wooden buildings; buildings with a steel frame structure, RC structure, or SRC structure mixed with wooden structure; and the like.

The fire-resistant structure of the present embodiment may be a structure in which the non-combustible material, the panel insulation material, the gypsum board, and the wood material are laminated in this order.
The wood material is preferably a material constituting a wood material structural part of a building. Examples of the wood material structural part include floors, walls, underfloors (ceilings), roofs, columns, beams, frames, etc., and the wood material may be applied to some of these. Among these, floors and underfloors are preferred, and underfloors are more preferred.

FIG. 4 shows an example of a floor and an under-floor (ceiling) to which the fire-resistant structure of this embodiment is applied.
A gypsum board 4, a panel insulation material 3, and a non-combustible material 2 are laminated in this order on a wooden material 5 (floor underlayment, etc.) of the floor to form a fire-resistant structure of the floor. The end faces of the gypsum boards 4 are butted together on the floor underlayment, and the gypsum boards 4 are connected to the entire surface so as to cover the entire surface of the floor underlayment. The end faces of the panel insulation material 3 are butted together on the gypsum board 4, and the panel insulation material 3 is connected to the entire surface so as to cover the entire surface of the gypsum board 4. In this example, the connection part of the panel insulation material and the connection part of the gypsum board are mutually orthogonal and shifted without overlapping. The floor in FIG. 4 is provided on the entire surface of the floor underlayment, which is a wooden material, and the entire surface is the fire-resistant structure of this embodiment.
Under the wooden material 5 (rough girders) under the floor, gypsum board 4, panel insulation material 3, and non-combustible material 2 are layered in this order to form a fire-resistant structure under the floor. In the floor underside of Fig. 4, the wooden material 5 (rough girders) is connected to a part of the gypsum board 4. The ceiling rough girders have a fire-resistant structure of non-combustible material 2/panel insulation material 3/gypsum board 4/wooden material 5, and the part sandwiched between the rough girders (the part where the rough girders and gypsum boards are not in contact) has a three-layer fire-resistant structure of non-combustible material 2/panel insulation material 3/gypsum board 4.

When the fireproof structure of this embodiment is installed in a structural part that separates the indoors from the outdoors, such as an exterior wall, floor, or roof, each component may be stacked on the indoor side of the wood material in the structural part, or on the outdoor side, or may be installed both indoors and outdoors.

The fire-resistant structure of this embodiment may have a finishing material applied to the non-combustible material surface.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Example 1
The following materials were stacked in the order listed below and fixed with screws to create a fireproof structure consisting of a calcium silicate board/phenol foam/reinforced gypsum board laminate with a length of 300 mm and a width of 300 mm, and the wood material and the reinforced gypsum board were fixed with screws so that they were in contact with each other (Figure 1).
- Calcium silicate board (manufactured by Nippon Insulation Co., Ltd.), thickness 15 mm
- Phenol foam (manufactured by Asahi Kasei Construction Materials Co., Ltd.), thickness 20 mm
- Reinforced gypsum board (manufactured by Yoshino Gypsum Co., Ltd.), 2 sheets of 15 mm thick - Wood material (cedar laminated wood: grade E65-F255), 105 mm thick

(Comparative Example 1)
A calcium silicate board/reinforced gypsum board/phenol foam laminate was produced in the same manner as in Example 1, except that the order of lamination of the phenol foam and the reinforced gypsum board was changed, and the wood material and the phenol foam were fixed with screws so that they were in contact with each other (Figure 3).

[evaluation]
The laminates obtained in the examples and comparative examples were evaluated for fire resistance by the following method.
In accordance with the ISO834 heating program, the test was performed for a total of 480 minutes, with a heating time of 120 minutes and a cooling time of 360 minutes after heating and cooling.

In Example 1, the wood surface temperature was a maximum of 155° C. at the end of the test after 120 minutes of heating. On the other hand, in Comparative Example 1, the wood surface temperature was a maximum of 210° C.
In Example 1 and Comparative Example 1, heating was performed for 120 minutes, and by the end of the test, no flame erupted or was emitted to the non-heated side, and no damage such as cracks through which flames could pass occurred.
After the test, each member was peeled off and the surface of the wood material was observed. The fire-resistant structure of Example 1 was not carbonized and met the criteria for a two-hour fire-resistant structure (Figure 5). On the other hand, the surface of the laminate of Comparative Example 1 was carbonized and did not meet the criteria for a two-hour fire-resistant structure (Figure 6).

Example 2
A fireproof structure was created in the same manner as in Example 1, except that the thickness of the members was changed as follows, and the wood material and the reinforced gypsum board were fixed with screws so that they were in contact with each other (Figure 1). Note that general course-thread screws were used for fixing.
・Calcium silicate board, thickness 20 mm
- Phenol foam, thickness 40mm
- Reinforced gypsum board, thickness 21 mm
A fire resistance test was conducted under the same conditions as in Example 1. Example 2 was heated for 120 minutes, and the maximum surface temperature of the wood by the end of the test was 158° C. By the end of the test, there was no flame erupting or ignition on the non-heated side, and no damage such as cracks through which flames could pass occurred. Furthermore, when each member was peeled off and the surface of the wood material was observed, the fire-resistant structure of Example 2 was not carbonized, and met the criteria for a 2-hour fire-resistant structure.

1 Fireproof structure 2 Non-combustible material 3 Panel insulation material 4 Gypsum board 5 Wood material 6 Reinforced gypsum board (a)
7 Aluminum sheet 8 Reinforced gypsum board (b)

Claims (10)

The non-combustible material, the panel insulation material, and the gypsum board are laminated in this order with each component in contact with each other,
The thickness of the gypsum board is less than 36 mm,
The non-combustible material is a calcium silicate board.
A fire-resistant structure for use in a building including said wood material, characterized in that at least a portion of said gypsum board is laminated with a wood material that is a material constituting the ceiling of the building. The non-combustible material, the panel insulation material, and the gypsum board are laminated in this order with each component in contact with each other,
The thickness of the gypsum board is less than 36 mm,
The panel insulation is a phenolic foam board.
A fire-resistant structure for use in a building including said wood material, characterized in that at least a portion of said gypsum board is laminated with a wood material that is a material constituting the ceiling of the building. 2. The fire resistant construction of claim 1, wherein said panel insulation is a phenolic foam board. The fire-resistant structure according to any one of claims 1 to 3 , wherein the density of the panel insulation is 10 to 60 kg/ ^m3 . The fireproof structure according to any one of claims 1 to 4 , wherein the moisture permeability coefficient of the panel insulation is 30 to 290 ng/( ^m2 ·s·Pa). The fire-resistant structure according to any one of claims 1 to 5 , wherein the thermal conductivity of the panel insulation is 0.018 to 0.050 W·m ⁻¹ ·K ⁻¹ . The gypsum board, the panel insulation material, and the non-combustible material are laminated in this order on the wood material,
The gypsum boards are connected to each other over the entire surface so as to cover the entire surface of the wood material,
The panel insulation material is connected to the entire surface of the gypsum board by butting the end faces together,
The joints of the panel insulation material and the joints of the gypsum board are offset without overlapping,
The fireproof structure according to any one of claims 1 to 6. The fire-resistant structure according to any one of claims 1 to 7, which uses the gypsum boards having a total thickness of 35 mm or less and satisfies the criteria for a two-hour fire-resistant structure in a fire resistance performance test conducted in accordance with ISO 834. The fireproof structure according to any one of claims 1 to 8 , wherein the non-combustible material, the panel insulation material, the gypsum board, and the wood material are laminated in this order with each member in contact with the other members. A building comprising the fire-resistant structure according to any one of claims 1 to 9 .

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