JP2013142246A - Fireproofing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fireproofing structure having an extremely high fire resistance based on a burning margin design.SOLUTION: A fireproofing structure includes a wooden structural material of a building, of which the surface is covered with a laminate composed of a burning margin layer formed of thin wooden plate material and a fireproofing layer formed of foam fire-resistant material. The thin plate material which constitutes a burning margin layer is provided with a single or a plurality of gaps or cuts.

Description

  The present invention relates to a fireproof covering structure in which a fireproof covering is applied to a wooden pillar in a building such as a wooden house and other wooden structures.

  A fire-resistant design that can provide a burning allowance on the surface of a structural material such as a wooden pillar in a building, and can increase the cross section by the amount of the burning allowance to delay carbonization in the center of the structural material is called “burning allowance design”. In burning allowance design, wood with a large cross section for burning allowance may be used as the structural material, or a structural material with a wood board thickness necessary for burning allowance attached to the surface of the core material that becomes the core of the pillar It may be used as In the burning allowance design, when a misfire occurs in a house and the flame reaches the pillar, the wood in the burning allowance part burns to form a heat insulating carbonized layer, delaying the burning of the core material (pillar body), Or is expected to prevent.

  However, in the above-mentioned burn allowance design, the cross section is enlarged by the amount of the burn allowance, but the burn allowance consisting only of wood needs to have a considerable thickness, which increases the weight of the structural material, There was a problem that the weight increased.

  In the fireproof coating structure according to Patent Document 1 below, a thermally expandable resin composition containing a specific kind of synthetic resin, a thermally expandable layered inorganic substance, and an inorganic filler around the surface side of the wooden structure body. Disclosed is a fire-resistant coating structure that is coated with a fire-resistant coating material, and has a protective treatment such as adhesion with an adhesive or fastening with a fastener such as a screw or tucker on the joint, which is a bonded portion of the fire-resistant coating material doing.

  However, in the fireproof covering structure disclosed in Patent Document 1, there is a problem that sufficient fireproof performance cannot always be obtained because only the fireproof covering material is covered around the surface of the wooden structure.

(Idea 1)
With respect to the above-described problems of the prior art, a fireproof covering structure having the following configuration can be proposed. For example, when the wooden structure material is a pillar having a quadrangular cross section, the four surfaces of the wooden structure material 2 in the fireproof covering structure 1 are covered with a foamable fireproof material layer 3 as shown in FIG. The layer 3 is further covered with a thin plate material 4. The thin plate material 4 is attached at the joint 5. In FIG. 1, FIG. 3, FIG. 6 and the like described later, the thickness of the refractory material layer and the thin plate material is exaggerated for convenience of illustration.

  In the fireproof covering structure shown in FIG. 1, since the thin plate material 4 burns to form a heat insulating carbonized layer in the event of a fire, and the inner fireproof material layer 3 foams to form a heat insulating layer, the fireproof material layer 3 A good fire and heat resistant sealing is formed by the synergistic effect of the sheet material 4 and the thin plate material 4 so that the combustion heat is hardly transmitted to the wooden structure material 2, and it can be expected that the fire resistant material layer 3 stops burning. In addition, there exists an effect that the thin board | plate material 4 has the advantage of the beautiful appearance, fragrance, humidity control property, touch, etc. of a wooden material.

(Idea 2)
Furthermore, as an improvement of the above idea 1, it is considered that the laminated wooden member disclosed in the following Patent Document 2 is used for the fireproof covering structure instead of each of the above-mentioned one fireproof material layer 3 and the thin plate material 4. It is done. As shown in FIG. 2, this laminated wooden member 16 is a fireproof plywood in which a plurality of wooden veneers 17 and an adhesive layer 18 made of a foamable fireproof material are alternately laminated. This corresponds to a configuration in which the thickness of the layer 3 and the plate material 4 is reduced and repeatedly laminated.

  By using the laminated wooden member 16 that is a fire-resistant plywood for the wooden structure material 2, the heat insulating property is continuously expressed sequentially from the adhesive layer 18 on the surface side (fire side) of the laminated wooden member 16 in the event of a fire. Therefore, a fireproof covering structure having a higher level of fireproof performance can be configured. Further, by increasing or decreasing the number of laminated single plates 17 and adhesive layers 18, it is possible to correspond to the degree of fire resistance required for the fireproof coating structure.

JP 2003-293482 A JP 2010-242331 A

  By the way, in the fireproof covering structure 1 shown in FIG. 1, the thin plate material 4 is combusted and carbonized at the time of a fire to form a brittle heat insulating carbonized layer and the refractory material layer 3 is foamed. Also in the fireproof covering structure using the laminated wooden member 16 shown in FIG. 2, the wood veneer 17 burns and carbonizes during a fire to form a brittle heat insulating carbonized layer and the adhesive layer 18 foams. Therefore, in these fireproof covering structures, it is common knowledge that a good fireproof and heat resistant sealing is configured for the wood structure material 2.

  However, as a result of further research by the inventor of the present application, it was found that the wood structure material 2 may be heated to a temperature near the carbonization temperature or a temperature range exceeding the carbonization temperature in the event of a fire. This point means that the configurations of the concept 1 and the concept 2 leave room for further improvement.

  Therefore, the present invention provides a technical problem to be solved to provide a specific measure for such further improvement.

  In the process of pursuing the means for solving the above problems, the inventor of the present application has a carbonization temperature range of about 250 to 270 ° C. of the plate material 4 and the single plate 17 made of wood in the configuration of the idea 1 and the idea 2, We paid attention to the fact that the foaming temperature range of the foamable refractory material constituting the refractory material layer 3 and the adhesive layer 18 is usually around 260 ° C. And since the carbonization temperature range of wood and the foaming temperature range of the foamable refractory material are close to each other or overlap, the foamable refractory material foams before the plate material 4 and the single plate 17 are sufficiently carbonized and become brittle. It has been found that the space for foaming / expansion is restricted by the covering plate material 4 or the single plate 17 and cannot be sufficiently foamed / expanded. The present invention has been completed based on such findings.

(Configuration of the first invention)
The structure of 1st invention for solving the said subject is the lamination | stacking comprised by using the burning allowance layer which consists of a wooden thin board | plate material, and the refractory material layer which consists of a foam refractory material for the surface of the wooden structure material of a building It is a fireproof covering structure which is covered with a body and the thin plate material constituting the burning allowance layer has one or more cracks or notches.

  In the first invention, the term “crack” refers to a cut that naturally occurs based on drying shrinkage or the like of a thin plate material, and the “cut” refers to a cut that is artificially formed by processing the thin plate material.

(Configuration of the second invention)
According to a second aspect of the present invention for solving the above-mentioned problem, in the fireproof covering structure according to the first aspect of the present invention, the laminate includes a burning allowance layer made of a thin wood material and a fireproof material layer made of a foamed fireproof material. The fireproof plywood is alternately laminated in three or more layers, and at least one layer of the thin plate material constituting the fireproof plywood has one or more cracks or cuts.

  In the second invention, the outermost layer in the refractory plywood may be a refractory material layer or a burning allowance layer, and the innermost layer may be a refractory material layer or a burning allowance layer.

(Configuration of the third invention)
The structure of the 3rd invention for solving the said subject is the range of 1-5 mm in the thickness of the sheet material of the burning allowance layer which constitutes a fireproof plywood in the fireproof covering structure concerning the 2nd invention, It is a fireproof covering structure whose thickness of a fireproof material layer exists in the range of 1-5 mm.

(Configuration of the fourth invention)
The structure of the 4th invention for solving the said subject is the fireproof covering structure which concerns on the said 2nd invention or the 3rd invention, By making the lamination | stacking number of the refractory material layers in a fireproof plywood into 2 layers-6 layers. , A fireproof coating structure that meets the requirements for 45 minute fireproof performance by heating the ISO 834 standard heating temperature curve.

(Structure of the fifth invention)
The structure of 5th invention for solving the said subject is the fireproof coating structure which concerns on the said 2nd invention or 3rd invention, By making the lamination | stacking number of the refractory material layers in a fireproof plywood into 3-8 layers. , A fireproof coating structure that meets the requirements for 60 minute fireproof performance by heating the ISO 834 standard heating temperature curve.

(Structure of the sixth invention)
According to a sixth aspect of the present invention for solving the above problem, in the fireproof covering structure according to the first aspect of the invention, the laminated body is one layer of the refractory material layer on the inner layer side and one layer of the burning allowance layer on the outer layer side. It is a fireproof covering structure in which a groove-like space that opens to the refractory material layer side is formed along the joint portion in the joint portion of the thin plate material that constitutes the burning allowance layer.

(Structure of the seventh invention)
The structure of the seventh invention for solving the above-mentioned problem is that, in the fireproof coating structure according to the sixth invention, a part or all of the groove-like space formed in the joint portion of the thin plate material is filled with a foamed refractory material. It is a fireproof covering structure.

  In the seventh aspect of the invention, "filling a part of the grooved space with the foamed refractory material" does not mean "filling part of the grooved space along the longitudinal direction of the grooved space with the foamed refractory material" This means that the foamed refractory material is filled to the extent that it occupies a part of the cross-sectional area of the space over the entire length of the groove-like space in the longitudinal direction.

(Configuration of the eighth invention)
According to an eighth aspect of the present invention for solving the above problems, in the fireproof covering structure according to the sixth or seventh aspect of the present invention, the backside of the refractory material layer is made of wood along the joints of the thin plate material of the burning allowance layer. This is a fireproof covering structure in which a notch-like space is provided in the structural material, and the notched space is filled with a foamed refractory material.

(Structure of the ninth invention)
According to a ninth aspect of the present invention for solving the above-described problem, in the fireproof covering structure according to any one of the first to eighth inventions, the foamed refractory material constituting the refractory material layer is applied with a foamed refractory paint. It is a fireproof covering structure that is a thin molded body of foamed refractory material.

  In the ninth invention, the foamed refractory paint and the foamed refractory material are substantially the same except that the foamed refractory paint includes a solvent that is water or an organic solvent and is in the form of a liquid paint.

(Configuration of the tenth invention)
According to a tenth aspect of the present invention for solving the above-mentioned problems, in the fireproof covering structure according to the ninth aspect of the present invention, the foamed refractory material contains a water-soluble alkali silicate, or a carbonizing agent or a thermally foamable material. A fireproof covering structure containing a foaming agent and a synthetic resin.

  In the fireproof covering structure according to Idea 1 and Idea 2, as described above, foaming / expansion starts when the foamed refractory material reaches a temperature range of around 260 ° C. during a fire. However, at that time, the thin plate material having a carbonization temperature range of about 250 to 270 ° C. is not sufficiently carbonized and brittle. Therefore, the space for foaming / expansion of the foamed refractory material is restricted by the restraining force of the thin plate material that is covered. As a result, as shown in FIG. 3 (a), the foamed refractory material 3 cannot be sufficiently foamed / expanded, and its fireproof / heatproof sealing is insufficient, so that the wood structure material 2 to be protected is sufficiently prevented from being carbonized / burned. Can not.

  However, in the first invention, even if the thin plate material constituting the burning allowance layer is not sufficiently carbonized, the thin plate material is easily divided along the cracks and cuts by the foaming / expansion pressure of the foamed refractory material. In addition, the interval between the divided thin plate materials also expands as the foamed refractory material expands. Therefore, the thin plate material does not have a binding force that restricts the foaming / expansion space of the foamed refractory material. Therefore, as shown in FIG. 3B, the foamed refractory material 3 can be sufficiently expanded and expanded.

  As a result, the action that the thin plate material 4 burns to form a heat insulating carbonized layer and the action that the refractory material layer 3 foams to form a heat insulating layer are fully expressed simultaneously. Therefore, due to the good synergistic effect of the refractory material layer 3 and the thin plate material 4, sufficient fire and heat resistant sealing for the wooden structure material to be protected is configured, and carbonization and combustion of the wooden structure material can be effectively and sufficiently prevented. .

  According to the second invention, when the fire is sequentially burned from the outer layer side of the fire-resistant plywood which is a laminated body in the event of a fire, the fire-resistant material layer repeatedly appears and expresses heat insulation. You can expect to burn out in your body.

  In addition, because of such a relationship, the thin plate material used for the fire-resistant plywood can be formed to be particularly thin as compared with the conventional ordinary burning substitute plate material. Accordingly, all the thin plate materials constituting the fire-resistant plywood may be provided with cracks and cuts, but as long as at least one layer of the thin plate material is provided with cracks and cuts, the “foamed refractory material as in the first invention” The thin plate material is divided by the pressure of foaming / expansion, and the foamed refractory material is sufficiently foamed / expanded.

  When the outermost layer of the fire-resistant plywood is a burn-in layer, the advantages such as the beautiful appearance and fragrance of the wood material in the fire-resistant covering structure, humidity control, and touch are ensured.

  As in the third invention, when the thickness of the thin plate material and the refractory material layer constituting the fire-resistant plywood that is a laminate is in the range of 1 to 5 mm, respectively, while forming the refractory plywood thin as a whole, The effect can be secured. Specifically, when the thickness of the thin plate material is 1 mm or more, good woody materials such as fragrance, appearance, and touch can be secured, and by making the thickness 5 mm or less, the thickness and structure of the burning portion It is possible to minimize the decrease in strength. Also, if the thickness of the refractory material layer is 1 mm or more, the foamed refractory material can be foamed well in the event of a fire to obtain sufficient heat insulation performance (heat insulation performance, fire resistance performance), and the thickness should be 5 mm or less. Thus, the thickness of the entire refractory plywood can be reduced, and when the refractory material layer is foamed during a fire, it can be prevented from falling off the thin plate material due to its own weight.

  Regarding the fourth and fifth inventions, the fire resistance performance of the fireproof plywood increases as the number of layers of the fireproof material layers increases, but the fireproof plywood becomes thicker by that amount. It is desirable to keep it within the minimum range where performance can be obtained. In the fourth aspect of the invention, it is possible to obtain a fire resistance performance of 45 minutes by heating according to the standard heating temperature curve of ISO834 by configuring the fireproof plywood with two to six layers of fireproof material layers. . In the fifth invention, it is possible to obtain a fire resistance performance of 60 minutes by heating the ISO 834 standard heating temperature curve by configuring the fireproof plywood with three to eight layers of fireproof material layers. .

  According to the sixth invention, since the same effect as the first invention is ensured, the groove-like space that opens to the refractory material layer side is formed along the joint portion of the thin plate material constituting the burning allowance layer. In the event of a fire, part of the foamed refractory foam is inductively introduced into the grooved space. Therefore, even if an open portion occurs in the joint portion of the thin plate material, the open portion is quickly closed by the fire-resistant foam, and the wood structure as the core material is strongly fire-proof / heat-resistant sealed.

  Furthermore, since the outer layer side is a burn-in layer, the advantages such as the beautiful appearance and fragrance of the wood material in the fireproof covering structure, humidity control, and touch are ensured.

  According to the seventh aspect, since the foamed refractory material is filled in part or all of the groove-like space formed in the same manner as the sixth aspect, the fire-resistant foam is formed along the joint portion of the thin plate material in the event of a fire. Is produced in large quantities. Therefore, the opening part generated in the joint portion of the thin plate material is quickly and more sufficiently closed. As a result, the wood structure as the core material is strongly fire-resistant and heat-resistant sealed.

  According to the eighth invention, the foamed refractory material is filled in the notch-like space provided in the wooden structure material along the joint portion of the thin plate material. The foamed refractory material of the refractory material layer being expanded is foamed so as to be pushed out toward the opening portion of the joint portion of the thin plate material. Therefore, the opening portion generated in the joint portion is quickly and sufficiently closed, and the wood structure as the core material is strongly fire-resistant / heat-resistant sealed as in the case of the seventh invention.

  As defined in the ninth invention, as a fireproof material layer made of foamed fireproof material, a foamed fireproof paint is applied and dried, or a foamed fireproof material with a thin molded body (size applicable to a wooden structure material) Can be preferably used.

  As specified in the tenth invention, as the foamed refractory material, (1) one containing a water-soluble alkali silicate, or (2) one containing a carbonizing agent, a heat-foaming foaming agent and a synthetic resin. preferable.

It is sectional drawing which shows the structure of the fireproof covering structure which concerns on the idea 1. FIG. It is sectional drawing of the fireproof plywood used for the fireproof coating structure which concerns on the idea 2. FIG. 3 (a) and 3 (b) are diagrams for explaining the effect of the first invention. 4 (a) to 4 (f) show groove-like spaces formed at the corners or flat joints of the fireproof covering structure. FIGS. 5A to 5B show a notch-like space provided in the wooden structure material and a foamed refractory material filled in the notch-like space. It is sectional drawing which shows the structure of the fireproof covering structure which concerns on an Example. It is a graph which shows the result of the evaluation experiment of an Example. It is a graph which shows the result of the evaluation experiment of an Example. It is a graph which shows the result of the evaluation experiment of an Example. It is a graph which shows the result of the evaluation experiment of a comparative example.

DESCRIPTION OF SYMBOLS 1 Fireproof covering structure 2 Wood structure material 3 Fireproof material layer 4 Thin plate material 5 Joint part 6 Groove-shaped space 7 Notch-shaped space 8 Foam fireproof material 11 Fireproof covering structure 12 Wood structure material 13 Laminated body 14 Fireproof material layer 15 Thin Board material 15a Gap 16 Glue wooden member 17 Single board 18 Adhesive layer a Site a
b Site b

  Next, embodiments of the present invention will be described including the best mode.

(Fireproof coating structure)
The fireproof covering structure according to the present invention covers the surface of a wooden structure material of a building with a laminate composed of a burning allowance layer made of a thin wood material and a fireproof material layer made of a foamed fireproof material. In addition, the thin plate material constituting the burning allowance layer has one or more cracks or notches.

  Between the wood structure material and the refractory material layer or the thin sheet material for fire substitute, or between the refractory material layer and the thin sheet material for fire substitute, either by the adhesive action of the refractory material layer itself, by adhesion with an adhesive, or by nails, screws. They can be joined using an appropriate joining means such as fixing with a fastener such as a screw.

  A specific embodiment of such a fireproof covering structure is not limited, but as a typical embodiment, a fireproof covering structure using a fireproof plywood, which will be described later, and a single burning allowance layer and a fireproof material layer. And a fireproof covering structure using

[Wood structure material]
The wooden structural material in the fireproof covering structure refers to various wooden structural materials in wooden houses and other buildings. As a typical wooden structure material, a prismatic column or a columnar column is exemplified. As pillars, in addition to the pillars with the entire peripheral surface exposed, a part of the pillars embedded in the wall of the building and the part of the pillars with the part exposed are also subject to fireproof coating. . Further, structural materials such as so-called “beams” are also targeted. Furthermore, in addition to these columnar (bar-shaped) structural materials, plate-shaped or planar or curved structural materials that constitute wall surfaces, floor surfaces, ceiling surfaces, and the like are also subject to fireproof coating. The present invention is particularly effective for columnar (bar-shaped) structural materials such as columns and beams.

[Burning layer constituting the laminate]
The burning allowance layer constituting the laminated body is made of a thin wood material. From the viewpoint of the appearance of the wooden structure material, it is preferable that the burning allowance layer constitutes the outermost layer of the fireproof covering structure, but from the viewpoint of the fire resistance performance of the wooden structure material, the outermost layer of the fireproof covering structure is the burning allowance layer. It may be a refractory material layer. Although the thin plate material can be formed thinner than the plate material for the burn-off in the conventional burn-off design, the preferred thickness is the fire-resistant covering structure using the fire-resistant plywood and the thin plate material of one layer each. And the fireproof covering structure using the fireproof material layer does not necessarily match.

  In the fire-resistant covering structure using the thin plate material and the fire-resistant material layer for each layer, a thin plate material having a thickness of 5 mm or more, for example, about 6 to 12 mm is used in consideration of the effect of the fire-resistant and heat-resistant sealing by the thin plate material. It is preferable. In addition, since the thin plate material is the outermost layer in this fireproof coating structure, it is not preferable to provide a crack or a cut reaching from one side of the thin plate material to the opposite surface in consideration of the appearance of the fireproof coating structure. .

  On the other hand, in the fire-resistant covering structure using the fire-resistant plywood, the structure in which the burning allowance layer (thin plate material) and the fire-resistant material layer composed of the foamed fire-resistant material are alternately laminated in total, It is possible and preferable to limit the thickness of the thin plate material to about 1 to 5 mm. And since it is possible to set individual thin plate materials in this way, it is particularly preferable if the fire-resistant plywood containing two or more layers of thin plate materials has at least one layer of thin plate material having one or more cracks or notches. As described in Examples below, if the thin plate material on the inner layer side of the laminate has cracks or cuts, even if the thin plate material on the outer layer side does not have cracks or cuts, it is described in the first invention. As described above, it is possible to ensure the effect of “division of the thin plate material by expansion / expansion pressure of the foamed refractory material and expansion of the interval between the divided thin plate materials”.

(Crack or cut)
The thin plate material constituting the burning allowance layer is provided with one or a plurality of cracks or notches described above with respect to the first invention. The shape of the single or multiple cracks and cuts in the thin plate material is not limited, but the depth, length, direction and plane shape are such that the thin plate material can be easily divided by the pressure of the foamed and expanded foam refractory material in the event of a fire It is preferable to provide. The formation direction of the cracks or cuts may be perpendicular to the front and back surfaces of the thin plate material, but may be oblique to the front and back surfaces of the thin plate material.

  The depth of the crack or the cut may reach from the one side surface of the thin plate material to the opposite surface, or may start from one side surface of the thin plate material and not reach the opposite surface. The cracks and cuts may be continuous over the entire length of the thin plate material, or may be intermittent (intermittent) intermittently over the entire length of the thin plate material. Things can be used. When “a crack or a cut extending from one side surface to the opposite surface of the thin plate material extends over the entire length of the thin plate material”, it means that a plurality of divided thin plate materials are substantially arranged in parallel. The planar shape of the cracks and cuts is preferably linear, and when a plurality of cracks and cuts are provided, they are preferably parallel, but are not limited to such embodiments. The cracks and cuts can be provided in any direction such as a longitudinal direction, a lateral direction, or an oblique direction of the thin plate material. In order to facilitate the division of the thin plate material based on the foaming / expansion pressure of the foamed refractory material, a crack or a cut provided in the direction along the grain of the thin plate material, particularly the mesh, is preferable.

  In a fire-resistant covering structure using a fire-resistant plywood, at least one layer of the thin-plate materials of the plurality of burning allowance layers constituting the fire-resistant plywood needs to have the cracks and cuts according to the above embodiment. In particular, it is preferable to provide the innermost side thin plate material with the cracks and cuts according to the above-described embodiment, but it is more preferable that each thin plate material constituting the refractory plywood has the cracks and cuts. For the thin plate material constituting the outermost layer of the refractory plywood, it is preferable in terms of appearance that no cracks or notches reaching from one side surface of the thin plate material to the opposite surface are provided.

(Particularly preferred embodiment of cracking or notching)
(1) It is preferable that the thin plate material is provided with cracks and cuts on the back surface in contact with the refractory material layer, that is, the surface on the side receiving the foaming / expansion pressure of the foamed refractory material.

  (2) When the wooden structure material is a columnar member, it is preferable to crack or cut in the vertical direction, that is, in a direction parallel to the axial direction of the columnar member.

  (3) When the thickness of the thin plate material is 1.6 mm or more, the depth of cracking and cutting (depth in the direction perpendicular to the front and back surfaces of the thin plate material) is 0.8 mm or more, and the thickness of the thin plate material is 1 When it is less than 6 mm, the depth of cracking and cutting is at least half the thickness of the thin plate. Particularly preferably, the thickness of the thin plate material is 1.6 mm or more, and the depth of cracks and cuts is 1 mm or more.

(4) When the thin plate material has a plurality of cracks or cuts on the back side, the total length thereof is 20 m or more, more preferably 25 m or more per 1 m ^{2 of the} thin plate material.

  (5) It is particularly preferable that the thin plate material has a plurality of cracks or cuts in parallel or substantially in parallel. In this case, the mutual interval between adjacent cracks or cuts is preferably about 5 mm to 50 mm.

  (6) The width of the crack or notch itself is not limited, but is preferably 5 mm or less, and more preferably 2.5 mm or less.

[Refractory material layer constituting the laminate]
As the foam refractory material which is a constituent material of the refractory material layer constituting the laminate, a foamed refractory paint coating layer or a thin molded product of the foam refractory material is preferably exemplified. The “foamed refractory paint coating layer” refers to a layer obtained by applying a foamed refractory paint and drying it. The “foamed refractory thin molded product” refers to a thin molded material of foamed refractory material in the form of a sheet or board, which is used after being cut and adjusted to a suitable size in advance.

  The preferred thickness of the refractory material layer is different between the refractory covering structure using the refractory plywood and the refractory covering structure using the one burning allowance layer and the refractory material layer.

  Foamed refractory material (foamed refractory paint or molded product of foamed refractory material) does not change its shape at room temperature, but is a material that forms a heat insulation layer by foaming by heating at the time of fire, etc. In addition, the thermal insulation effect of the foam insulation layer suppresses the temperature rise of the wooden structure material and exhibits fire prevention performance.

  Various known materials can be used as the foam refractory material, and the type and composition thereof are not necessarily limited, but those containing a carbonizing agent, a thermally foamable foaming agent and a synthetic resin are preferable.

(Carbonizing agent, heat-foaming foaming agent, synthetic resin)
In the foamed refractory material containing the carbonizing agent, the thermally foamable foaming agent, and the synthetic resin, the carbonized agent forms a carbonized layer by heating, and the thermally foamable foaming agent foams the carbonized layer. Synthetic resin is a binder (binder).

  A carbonizing agent reacts by heating at the time of a fire etc. and forms a carbon skeleton. As such a carbonizing agent, what consists only of carbon, oxygen, and hydrogen, such as a polyhydric alcohol, water-soluble polysaccharide, phenols, and expansive graphite, is mentioned.

  Among the carbonizing agents, expandable graphite is particularly preferable because it has a self-foaming property and can form a heat insulating layer without using a foaming agent. Expandable graphite has the property that when heated, the compound present between the graphite layers is thermally decomposed and the whole expands. The expandable refractory material to which expandable graphite is added expands by heating during a fire or the like to form a foam heat insulating layer. Examples of such expandable graphite include graphite acidic sulfate, sodium graphite, potassium graphite, halogenated graphite, graphite oxide, aluminum chloride graphite compound, and ferric chloride graphite.

A foaming agent decomposes | disassembles by heating and generate | occur | produces nonflammable gas, such as nitrogen, ammonia, a carbon dioxide gas, Comprising: A carbonized layer is foamed with the generated gas. In addition, the generated noncombustible gas can be expected to form a noncombustible gas layer on the surface of the carbonized layer and suppress the conduction of combustion heat.

Such blowing agents include dicyandiamide, azodicarbonamide, hexamethoxymethylmelamine and its derivatives, urea, melamine, butylmelamine and trimethylolmelamine, hexamethylolmelamine, urea, dimethylurea, guanylureaphosphate, aminoguanylurea And organic foaming agents such as urea formaldehyde, aminoacetic acid and guanidine, and inorganic foaming agents such as sodium bicarbonate, ammonium bicarbonate and ammonium carbonate.

In addition to the above foaming agent, those that react with the carbonizing agent to generate gas when heated together with the carbonizing agent can also be used as the foaming agent. Examples of such foaming agents include ammonium phosphate, ammonium polyphosphate, melamine phosphate, melamine polyphosphate, aluminum phosphate, magnesium phosphate phosphate, sulfamate (sulfamine ammonium, etc.), Examples thereof include borates (such as ammonium borate).

  The foaming agent, ammonium phosphate or ammonium polyphosphate, has a decomposition temperature of around 260 ° C., and the polyhydric alcohol (carbonizing agent) pentaerythritol, dipentaerythritol, tripentaerythritol, polypentaerythritol. Decomposes at approximately the same temperature.

  Therefore, when the above-mentioned ammonium phosphate and / or ammonium polyphosphate is used as the foaming agent and these polyhydric alcohols are used as the carbonizing agent, the foamed refractory material can be easily foamed at a large expansion ratio.

  Further, when titanium dioxide is used as a coloring pigment in the foamed refractory material having such a composition, since titanium dioxide acts as a catalyst in the reaction between polyhydric alcohol and ammonium phosphate and / or ammonium polyphosphate during heating, foaming is performed. The reaction can be further promoted.

  The effect of increasing the expansion ratio of the foamed refractory material as described above is that when melamine or the like having a decomposition temperature of around 360 ° C. is used among organic foaming agents, the foaming is further performed after the carbonizing agent forms a carbonaceous skeleton. Can be achieved, and the effect is greater.

  Synthetic resin is a binder for foamed refractory material at room temperature and is used to maintain the shape of the foamed refractory material until the foamed refractory material is heated and the synthetic resin melts or burns out. .

  As the synthetic resin, melamine resin, acrylic resin, alkyd resin, vinyl chloride resin, vinyl acetate resin, ethylene-vinyl acetate resin, urethane resin, epoxy resin, silicone resin, polyester resin, or the like can be used. These resins may be used alone or may be copolymerized or may be used by mixing them. Further, as the form of these resins, those dissolved in a solvent or those dispersed as an emulsion are used.

(Other additives and additives in foam refractory materials)
The foamed refractory material containing the carbonizing agent, the foaming agent, and the synthetic resin can be added with various known additives and additives used for conventional fire-resistant paints and fire-resistant sheet materials other than the above-described components. . These additives and additives may be added within a range that does not hinder the function of the foamed refractory material to form a foam heat insulating layer.

  Examples of such additives and additives include inorganic fillers such as calcium carbonate, aluminum hydroxide, alumina, silica and ceramic powder, organic fillers such as foamed plastic powder, rock wool, slag wool, glass wool, ceramic fiber, Inorganic fibers such as silica fibers, organic fibers such as cellulose fibers and synthetic fibers, flame retardants such as halogen-based, phosphorus-based, and antimony trioxide-based surfactants, antifoaming agents, dispersants, wetting agents, and film-forming aids Solvents such as agents and antifreeze agents, coloring pigments, extender pigments, metal soaps, stabilizers, thickeners, preservatives, antifungal agents and the like can be used.

  Among the above-mentioned foamed refractory materials, those containing polyhydric alcohol as a carbonizing agent, containing ammonium phosphate and / or ammonium polyphosphate as a blowing agent, and further containing a synthetic resin are more preferable. In addition to these, those further containing the organic foaming agent are particularly preferred. Such a composition has a large foaming ratio, meaning “volume of the foamed refractory material after foaming / volume of the foamed refractory material before foaming”, and forms a foamed heat insulating layer with better heat insulation. Moreover, since the expansion ratio is large, it is excellent in the performance of closing the open portion of the joint portion generated by the shrinkage or warping of the burning substitute plate material.

(Preferred composition example of foamed refractory material)
As an example of a preferable blending ratio of each component in the foamed refractory paint and the foamed refractory paint, the synthetic resin is 200 to 500 mass in terms of solid content when the blending amount of the polyhydric alcohol is 100 parts by mass. Parts, the organic foaming agent is 80 to 150 parts by mass, and the total amount of ammonium phosphate and / or ammonium polyphosphate is 280 to 450 parts by mass. When the blending ratio of each component is within the above range, a foamed refractory material having particularly excellent fire resistance can be obtained.

  Moreover, when mix | blending titanium dioxide, it is preferable that the mixture ratio is 100-300 mass parts, when the compounding quantity of a polyhydric alcohol is 100 mass parts. If the blending amount of titanium dioxide is too small, the effect as a catalyst is not sufficient, and conversely if too large, the heat insulating layer becomes brittle.

[Fireproof covering structure using fireproof plywood]
As a laminated body in the fireproof covering structure, a fireproof plywood in which a total of three or more fireproof material layers made of a thin wood material and a fireproof material layer made of a foamed fireproof material are alternately laminated can be used. In this case, the foamed refractory material constituting the refractory material layer serves as an adhesive between the burning allowance layers. The thin plate material constituting the burning allowance layer is, for example, wood made from thinned wood and the like, and is often a thin plywood itself. In this case, the thickness of the thin plate material is about several mm, preferably in the range of 1 to 5 mm, particularly preferably in the range of 3 to 4 mm. The thickness of the refractory material layer is preferably in the range of 1 to 5 mm, and more preferably in the range of 1.5 to 3 mm. Therefore, the overall thickness of the refractory plywood is not so large.

  The number of refractory material layers in the refractory plywood is preferably 2 to 5 layers, more preferably 3 to 4 layers, in order to obtain 30 minutes fire resistance performance. In order to obtain a 45 minute fireproof performance, it is preferably 2 to 6 layers, more preferably 3 to 5 layers. Moreover, in order to obtain a 60-minute fireproof performance, it is preferably 3 to 8 layers, more preferably 4 to 6 layers.

  The fire resistance performance of the fireproof plywood increases as the number of fireproof material layers is increased, but the thickness of the fireproof plywood also increases, so the number of fireproof material layers is the minimum range where the required performance can be obtained, that is, What is necessary is just to set it as said range.

[Fireproof coating structure using one burn-out layer and a refractory layer each]
As a laminate in the fireproof covering structure, it consists of one fireproof material layer on the inner layer side and one burning allowance layer on the outer layer side, and it opens to the fireproof material layer side at the joint of the thin plate material that constitutes the burnup allowance layer It is also possible to use a laminated body in which groove-like spaces to be formed are formed along the joint portions.

  The thin plate material of the burning allowance layer covers the surface of the refractory material layer and constitutes the outermost layer of the refractory coating structure. Although the design guideline for determining the thickness of the thin plate material is not particularly limited, for example, the thickness can be designed in consideration of the time required for burning the burning substitute plate material at the time of a fire. There is a technical document that the burning rate in the thickness direction of a plate material during a fire is generally about 0.6 mm per minute. Based on this technical document, for example, if it is expected that the sheet material can last for 10 minutes in a fire, the thickness of the sheet material is preferably 6 mm. If the sheet material is expected to last 20 minutes, the thickness is 12 mm. It is preferable that

  The refractory material layer covers the surface of the wood structure material which is the core material of the fireproof covering structure, and the outer side thereof is further covered with a burning allowance layer. The thickness of the refractory material layer can be arbitrarily designed according to the type of foamed refractory material as a constituent material, the expected level of fire resistance, etc., but is preferably about 1 to 4 mm.

[Additional Embodiment of Fireproof Coating Structure]
Not only when the wooden structural material is a pillar with a quadrangular cross section, but also when the wooden structural material is a plate-like structural material constituting a wall surface, floor surface, ceiling surface, etc., those surfaces are made into a single thin plate material. In many cases, it is difficult to cover with a sheet, so that a joint portion for attaching a thin plate material can be formed. In the joint portion, it is likely that the thin plate material is warped or contracted during a fire and an open portion is likely to be generated, and it can be expected that the refractory material layer of the inner layer of the thin plate material foams and closes the open portion of the joint portion. However, the additional embodiment described below is extremely effective in order to quickly and sufficiently close the opening portion generated in the joint portion in the event of a fire and to ensure particularly strong fire and heat resistant sealing against the wooden structure material. .

(Grooved space along the joint of the burning substitute plate material)
If a groove-shaped space that opens to the refractory material layer side is formed along the joint portion of the thin plate material, the refractory material layer is foamed and a part of the foam is inductively introduced into the groove-shaped space. Therefore, the flame and heat shielding effect at the joint opening portion is further improved. These embodiments are shown in FIGS.

  In FIG. 4A, a groove-like space 6 formed by cutting a part of both thin plate members 4 along the joints 5 at the corners of the thin plate member 4 is formed in a state opened to the refractory material layer 3 side. Has been. In FIG.4 (b), the groove-shaped space 6 formed by cutting a part of one thin board | plate material 4 along the joint part 5 of a corner | angular part is formed in the state opened to the refractory material layer 3 side. In FIG. 4C, a corner joint 5 is formed by attaching two thin plate members 4 each having a concave portion and a convex portion that can be engaged with each other in the cross-sectional shape. A groove-like space 6 formed by cutting a part of the thin plate material 4 is formed in an open state on the refractory material layer 3 side.

  In FIG.4 (d), the groove-shaped space 6 formed by cutting a part of both the thin board | plate materials 4 along the joint part 5 of the plane part of the thin board | plate material 4 is the refractory material layer 3 side which consists of a foam refractory material. It is formed in an open state. In FIG.4 (e), the groove-like space 6 formed by cutting a part of one thin plate material 4 along the joint portion 5 of the flat portion of the thin plate material 4 is the refractory material layer 3 side made of the foamed refractory material. It is formed in an open state. In FIG. 4 (f), a flat joint portion 5 is formed by attaching two thin plate members 4 having a concave portion and a convex portion that can be engaged with each other in the cross-sectional shape, and along the joint portion 5. A groove-like space 6 formed by cutting a part of one thin plate material 4 is formed in a state opened to the refractory material layer 3 side.

  Furthermore, a part or all of the groove-like space 6 of the joint portion 5 according to the embodiment shown in FIGS. 4A to 4F can be filled with a foamed refractory material in advance (not shown). In this case, the opening of the joint portion of the thin plate material generated at the time of the fire is blocked by the foamed refractory paint or the foamed refractory material previously filled in the groove-like space.

(Filling refractory foam into a notch-shaped space in a wooden structure)
On the back side of the refractory material layer made of foam refractory material, a notch-like space is provided in the wooden structure material along the joints of the thin plate material. The open portion of the joint portion is closed by allowing the foam of the refractory material to be pushed out to the open portion of the joint portion of the thin plate material. Therefore, extremely strong fire and heat resistant sealing is ensured for the wooden structure material.

  Such an embodiment will be described with reference to FIG. In the embodiment of FIG. 5 (a), joints 5 of the thin plate material 4 are formed at the corners of the fireproof covering structure, and on the back side of the fireproof material layer 3, cut into the wooden structure material 2 along the joints 5. A notched space 7 is provided, and the notched space 7 is filled with a foam refractory material 8. In the embodiment of FIG. 3 (b), the joint portion 5 of the thin plate material 4 is formed on the flat portion of the fireproof covering structure, and on the back side of the fireproof material layer 3, the wood structure material 2 is cut along the joint portion 5. A notched space 7 is provided, and the notched space 7 is filled with a foam refractory material 8.

  Next, examples of the present invention will be described. The technical scope of the present invention is not limited by the following examples.

[Example 1: Fireproof coating structure]
In this embodiment, a fireproof covering structure 11 whose sectional view is shown in FIG. The woody structural material 12 of the fireproof covering structure 11 is a prism having a cross section of a size of 100 mm × 100 mm. The four peripheral surfaces that are the surface of the wooden structural member 12 are covered with the same laminate 13 as the laminated wooden member 16 shown in FIG. The laminated body 13 has three layers of refractory material layers 14 and three layers of thin plate materials 15 that are alternately laminated so that the innermost layer is the refractory material layer 14 and the outermost layer is the thin plate material 15. Plywood.

  The thickness of each refractory material layer 14 is 2 mm, and the thickness of each thin plate material 15 is 2.5 mm. Therefore, the thickness of the laminated body 13 around the wood structure material 12 in the fireproof covering structure 11 is 13.5 mm. Of the three-layered thin plate material 15, the two-layered thin plate material 15 on the inner layer side is divided with a gap 15a (cut) having a width of 2.5 mm. However, the thin plate material 15 of the outermost layer does not have such cuts or cracks, and the thin plate material 15 is attached to the four corners of the wooden structure material 12 without gaps, so that the beautiful appearance of the wooden structure material 12 is obtained. Is secured.

  The refractory material layer 14 is formed into a sheet by applying and drying a foam refractory paint having the following composition. The thin plate material 15 and the sheet-like refractory material layer 14 are bonded with an adhesive.

(Formation of foam fireproof paint)
Pentaerythritol: 100 parts by weight Melamine: 100 parts by weight Vinyl acetate / acrylic emulsion (solid content): 350 parts by weight Ammonium polyphosphate: 450 parts by weight Titanium dioxide: 200 parts by weight.

[Example 2: Evaluation of fireproof covering structure]
(Preparation of specimen)
As compared with the fireproof covering structure 11 according to Example 1, the following fireproof covering structures according to Examples 2-1 to 2-3 and Comparative Examples in which only the following points were changed were tested. Prepared as. The height of these columns is 1000 mm.

  Example 2-1: Among the three-layer thin plate material 15, the two-layer thin plate material 15 on the inner layer side is a single thin plate material that is not divided on the four peripheral surfaces of the wooden structure material 12. Instead of the gap 15a having a width of 2.5 mm, a thin plate material having a crack with a depth of about 1 mm in the same portion was used.

  Example 2-2: Among the three-layer thin plate material 15, the two-layer thin plate material 15 on the inner layer side is a single thin plate material that is not divided on the four peripheral surfaces of the wooden structure material 12. Instead of the gap 15a having a width of 2.5 mm, a thin plate material provided with a notch extending from one side surface of the thin plate material 15 to the opposite surface at the same portion was used.

  Example 2-3: Among the three-layered thin plate material 15, as the two-layered thin plate material 15 on the inner layer side, a thin plate material having a gap of 6 mm larger than that in the case of Example 1 was used.

  Comparative example: None of the three-layered sheet material has cracks or notches.

  In these prismatic fireproof covering structures, a site a and a site b which are center portions of two adjacent peripheral surfaces in the center portion in the vertical direction of the wooden structure material 12 (a height of 500 mm from the lower end) in advance. A small thermocouple was embedded in (see FIG. 6), and the lead wire was led out to the outside of the fireproof coating structure so that the surface temperature of the wood structure material at site a and site b could be constantly measured.

(Temperature evaluation of test specimen)
The fireproof coating structures according to the above Examples 2-1 to 2-3 and the comparative example are respectively put into a heating furnace and heated so that the temperature in the furnace rises according to the standard heating temperature curve defined in ISO834. The temperature change at site a and site b of the fireproof coating structure according to each example during the heating was measured over time.

  FIG. 7 shows the measurement results of Example 2-1, FIG. 8 shows the measurement results of Example 2-2, FIG. 9 shows the measurement results of Example 2-3, and FIG. 10 shows the measurement results of Comparative Example 2-1. Respectively. 7 to 10, a graph represented by “ISO” is a standard heating temperature curve defined in ISO834, a graph represented by “inside the furnace” is an actual temperature rising curve in the heating furnace, and “a”. , “B” are temperature rising curves measured at site a and site b, respectively.

  As can be seen from FIGS. 7 and 8, in the fireproof covering structure of Example 2-1 using a thin plate material having a crack of about 1 mm in depth, 45 minutes from the start of heating (indicated as 0:45 in the figure) Example of using a thin plate material provided with notches reaching a width from one side to the opposite side while the temperature rise at site a and site b at about 220 ° C. during the lapse of time (when the furnace temperature reached 900 ° C.) Even with the 2-2 fireproof covering structure, a result almost equal to that of Example 2-1 was obtained. This temperature is much lower than 265-270 ° C., which is the carbonization temperature range of the woody material.

  On the other hand, in the fireproof covering structure of Example 2-3 using a thin plate material having a gap of 6 mm which is a width exceeding 5 mm, when 45 minutes have elapsed from the start of heating (when the furnace temperature reaches 900 ° C.). The temperature rise at site a and site b was about 260 ° C. This temperature is considerably higher than those in Examples 2-1 and 2-2, but is slightly below the carbonization temperature range of the wood material.

  On the other hand, in the fireproof coating structure of the comparative example in which none of the three-layered thin plate materials has cracks or notches, the site a when 45 minutes have elapsed from the start of heating (when the furnace temperature reaches 900 ° C.) And the temperature rise of the site b reached about 300 ° C. and greatly exceeded the carbonization temperature range of the wood material.

(Evaluation of foaming and expansion of the refractory material layer of the specimen)
It is considered that the results of the temperature rise evaluation of Example 2-1 to Example 2-3 and the comparative example are caused by the difference in foaming / expansion degree of the refractory material layer in the fireproof coating structure. Therefore, after the temperature increase test, the furnace was stopped and allowed to stand for 1 hour, and then the specimens of the fireproof coating structures according to Example 2-1 to Example 2-3 and the comparative example were taken out of the furnace. The fireproof covering structure was cut in the radial direction of the column at the site a and the site b, and the average value of the thickness of the laminate 13 around the wood structure material 12 was obtained. As described above, the thickness of the laminate 13 before heating is 13.5 mm, and the increase from this value is due to foaming / expansion of the refractory material layer.

  The average value of the thickness of the laminated body 13 around the wood structure material 12 in the fireproof covering structure after the temperature rise evaluation was about 40 mm in Example 2-1, about 40 mm in Example 2-2, and Example 2-3. And about 30 mm in the comparative example.

  According to the present invention, there is provided a fire-resistant covering structure having extremely good fire resistance based on the burn-in allowance design.

Claims (10)

The surface of the wooden structural material of the building is covered with a laminate composed of a burning allowance layer made of wood thin plate material and a fireproof material layer made of foam refractory material, and constitutes a burning allowance layer A fireproof covering structure characterized in that the thin plate material to be provided has one or a plurality of cracks or cuts. The laminated body is a fire-resistant plywood in which a burning allowance layer made of a wooden thin plate material and a fire-resistant material layer made of a foamed refractory material are alternately laminated in total, and at least 1 constituting the fire-resistant plywood The fire-resistant covering structure according to claim 1, wherein the thin plate material of the layer has one or a plurality of cracks or notches. The thickness of the thin plate material of the burning allowance layer constituting the fireproof plywood is in the range of 1 to 5 mm, and the thickness of the fireproof material layer is in the range of 1 to 5 mm. Fireproof covering structure. The number of the refractory material layers in the refractory plywood is set to 2 to 6 to meet the requirement of 45 minutes fire resistance performance by heating of the standard heating temperature curve of ISO834. Or the fireproof covering structure of Claim 3. The number of the refractory material layers in the refractory plywood is set to 3 to 8 to meet the requirement of 60-minute fire resistance performance by heating of the standard heating temperature curve of ISO834. Or the fireproof covering structure of Claim 3. The laminated body is composed of one layer of the refractory material layer on the inner layer side and one layer of the burning allowance layer on the outer layer side, and a groove shape opening to the refractory material layer side at the joint portion of the thin plate material constituting the burnup allowance layer The fireproof covering structure according to claim 1, wherein a space is formed along the joint. The fireproof covering structure according to claim 6, wherein a part or all of the groove-like space formed in the joint portion of the thin plate material is filled with a foamed refractory material. A notch-like space is provided in the wooden structure material along the joint portion of the thin plate material of the burning allowance layer on the back side of the refractory material layer, and the notched space is filled with a foam refractory material. The fireproof covering structure according to claim 6 or claim 7. The foamed refractory material constituting the refractory material layer is obtained by applying and drying a foamed refractory paint, or a thin molded product of the foamed refractory material. The fireproof covering structure as described. The fireproof covering structure according to claim 9, wherein the foamed refractory material contains a water-soluble alkali silicate, or contains a carbonizing agent, a thermally foamable foaming agent, and a synthetic resin. body.