JP7100313B2 - Flame-retardant wood-based materials and fire-resistant structural members - Google Patents

Description

The present invention relates to a flame-retardant wood-based material and a fire-resistant structural member provided with the same.

In recent years, there has been increasing interest in large-scale fire-resistant wooden buildings, and at the same time, the development of structural members for buildings with fire-resistant performance is being promoted. As one of such fireproof structural members, as disclosed in Patent Document 1, a fireproof portion including a load support portion that supports the load of a building and a burnout layer that covers the surface of the load support portion. Glulam is known. According to this refractory laminated wood, it is possible to protect the load support portion in the event of a fire by preventing the combustion from propagating to the load support portion by the burnout layer.

The refractory laminated wood of Patent Document 1 includes a load-bearing portion and a plywood fixed to the surface of the load-bearing portion as a burn-off layer. In this plywood, the chemical-treated wood board and the untreated wood board (impregnated with the flame-retardant chemical) so that at least one layer on the side in contact with the load support portion becomes a chemical-treated wood board impregnated with a phosphoric acid-based flame-retardant chemical. It is constructed by stacking wood boards that are not used) and adhering the wood boards to each other. Then, this plywood is fire-resistant laminated by fixing one layer on which the chemical-treated wood board is arranged to the surface of the load-bearing portion using fasteners such as wood screws and nails. The wood is composed.

Japanese Unexamined Patent Publication No. 2009-174286

As described above, in Patent Document 1, among the plurality of wooden boards constituting the plywood, the wooden board in contact with the surface of the load supporting portion is impregnated with the flame retardant. Here, when an attempt is made to bond the plywood to the surface of the load supporting portion using an adhesive, it may not be possible to sufficiently secure the adhesive strength of the plywood due to the poor affinity between the flame retardant agent and the adhesive. be. This is partly due to the need to adhere at room temperature, in addition to the poor affinity between the flame retardant and the adhesive. Therefore, in Patent Document 1, the plywood is fixed to the load support portion by using a fastener.

However, in the fire-resistant laminated lumber of Patent Document 1, there is a concern that fasteners such as wood screws and nails serve as a combustion propagation path, and the combustion propagates to the load supporting portion. Therefore, it is difficult for this refractory laminated wood to reliably protect the load bearing portion in the event of a fire.

The present invention has been made in view of the above problems, and an object thereof is flame retardancy capable of ensuring sufficient adhesive force to the load supporting portion and more reliably protecting the load supporting portion. It is to provide a treated wood material and a fireproof structural member with the same.

The flame-retardant wood-based material according to one aspect of the present invention is adhered to the surface of the load-bearing portion of the fire-resistant structural member. This flame-retardant wood-based material has a plate-shaped core material impregnated with a flame-retardant agent, a first inner layer adhesive surface adhered to the surface of the load support portion, and a side opposite to the first inner layer adhesive surface. It is made of a wooden board including a second inner layer adhesive surface, which is a surface, and is overlapped with the core material in the plate thickness direction, and the core material is thermally pressure-bonded to the second inner layer adhesive surface with a thermosetting adhesive. It is equipped with an inner layer material that has been made. The core material is attached to the load supporting portion via the inner layer material. The inner layer material is a flame retardant untreated material that is not impregnated with the flame retardant.

Since the core material of this flame-retardant wood-based material is impregnated with a flame retardant agent, it can be used as a burn-stop layer by adhering to the surface of the load-bearing portion of the fire-resistant structural member. Thereby, when the load supporting portion is made of a combustible material (for example, wood or plastic), combustion of the load supporting portion can be suppressed. Further, when the load supporting portion is made of a non-combustible material (for example, steel), the temperature rise of the load supporting portion can be suppressed, and the thermal deformation of the load supporting portion can be suppressed.

Here, the inner layer material adhered to the surface of the load supporting portion is a flame-retardant untreated material that is not impregnated with a flame retardant. Therefore, when the inner layer material is adhered to the surface of the load supporting portion, good adhesive force to the load supporting portion can be ensured regardless of the affinity between the flame retardant agent and the adhesive. Therefore, since it can be securely fixed to the load support portion only with an adhesive, it is not necessary to use fasteners such as wood screws and nails, and there is also a problem that the fastener becomes a combustion and heat propagation path. Does not occur. Therefore, it is possible to prevent combustion and heat propagation to the load support portion and to protect the load support portion more reliably. Moreover, since the inner layer material is thermally pressure-bonded to the core material with a thermosetting adhesive, the inner layer material is surely adhered to the core material and the inner layer material is prevented from falling off from the core material. Can be done.

The flame-retardant-treated wood material is composed of a wooden board that sandwiches the core material in the plate thickness direction together with the inner layer material, and further includes an outer layer material that is thermally pressure-bonded to the core material with a thermosetting adhesive. May be good. The outer layer material may be a flame retardant untreated material that is not impregnated with the flame retardant.

According to this configuration, when the surface of the load-bearing portion is covered with a flame-retardant wood material and then the flame-retardant wood material is further covered with a decorative layer, the decorative layer is made of flame-retardant wood only with an adhesive. It can be securely fixed to the material. This is because the outer layer material in contact with the decorative layer is not impregnated with the flame-retardant agent, so even if the flame-retardant agent and the adhesive have a poor affinity, the adhesive force of the adhesive is not easily affected. Is.

In the flame-retardant treated wood material, the thickness of the inner layer material may be 0.5 mm or more and 10 mm or less.

If the thickness of the inner layer material is less than 0.5 mm, the flame retardant impregnated in the core material may seep out to the outermost surface of the flame-retardant wood material, and it may be thermally pressure-bonded to the core material. Is difficult. On the other hand, when the thickness of the inner layer material exceeds 10 mm, the inner layer material exposed on the abutting surface of the flame-retardant wood materials becomes a combustion and heat propagation path, and the combustion and heat propagate to the load support portion. There is a risk. Therefore, the thickness of the inner layer material is preferably 0.5 mm or more and 10 mm or less.

In the flame-retardant treated wood material, the core material has a plurality of wooden boards impregnated with the flame retardant agent, and the plurality of wooden boards are overlapped in the plate thickness direction and are thermally pressure-bonded to each other by a thermosetting adhesive. It may be configured by being done.

According to this configuration, a core material can be obtained by impregnating each of a plurality of wooden boards with a flame retardant and then superimposing them and thermally pressure-bonding them. As a result, the flame retardant can be uniformly impregnated in the entire core material.

The fireproof structural member according to another aspect of the present invention is used as a structural member of a fireproof wooden building. This fire-resistant structural member is bonded to a load support portion that supports the load of the building so as to cover the surface of the load support portion, and has a burn-off layer that prevents combustion or heat propagation to the load support portion. It is equipped with. The burn-off layer is made of the flame-retardant treated wood material of the present invention.

In this fire-resistant structural member, since the flame-retardant wood material of the present invention is adhered to the surface of the load-bearing portion as a burn-stop layer, the burn-stop is stopped only by the adhesive without using fasteners such as wood screws and nails. The layer can be reliably fixed to the surface of the load bearing. Therefore, it is possible to prevent the combustion and heat from propagating to the load support portion by using the fastener as a combustion and heat propagation path, and it is possible to more reliably protect the load support portion.

As is clear from the above description, according to the present invention, a flame-retardant treated wood material capable of ensuring sufficient adhesive force to the load-bearing portion and more reliably protecting the load-bearing portion and a flame-retardant treated wood material. It is possible to provide a fireproof structural member equipped with this.

It is a perspective view which shows typically the structure of the fire-resistant structural member which concerns on Embodiment 1 of this invention. It is a figure which shows typically the cross section of the fire-resistant structural member along the line segment II-II in FIG. It is a perspective view which shows typically the structure of the flame-retardant treated wood-based material which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the state of heat-pressing a laminated body. It is a figure which shows typically the cross section of the fireproof structural member which concerns on Embodiment 2 of this invention. It is a figure which shows typically the cross section of the fire-resistant structural member which concerns on other embodiment of this invention. It is a figure which shows typically the cross section of the fire-resistant structural member which concerns on other embodiment of this invention. It is a schematic diagram which shows the attachment position of a thermocouple to the surface of a load support part in a fire resistance performance evaluation test. It is a graph which shows the temperature change of the corner part of the load support part at the upper measurement position in an Example. It is a graph which shows the temperature change of the side part of the load support part at the upper measurement position in an Example. It is a graph which shows the temperature change of the corner part of the load support part at the intermediate measurement position in an Example. It is a graph which shows the temperature change of the side part of the load support part at the intermediate measurement position in an Example. It is a graph which shows the temperature change of the corner part of the load support part at the lower measurement position in an Example. It is a graph which shows the temperature change of the side part of the load support part at the lower measurement position in an Example. It is a graph which shows the temperature change of the load support part at the upper measurement position in the comparative example. It is a graph which shows the temperature change of the load support part at the intermediate measurement position in the comparative example. It is a graph which shows the temperature change of the load support part at the lower measurement position in the comparative example.

Hereinafter, the flame-retardant wood-based material and the fire-resistant structural member provided with the flame-retardant wood-based material according to the embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
<Fireproof structural member>
First, the configuration of the fireproof structural member 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view schematically showing the appearance of the fireproof structural member 1. FIG. 2 is a diagram schematically showing a cross section of the fireproof structural member 1 along the line segments II-II in FIG. 1.

The fireproof structural member 1 is used as a structural member (for example, a pillar or a beam) of a fireproof wooden building, and as shown in FIG. 1, is a wooden structural member having a substantially square columnar shape. The fireproof structural member 1 covers the load support portion 10 that supports the load of the building, the burn-off layer 20 that is adhered so as to cover the surface 11 of the load support portion 10, and the surface 22 of the burn-stop layer 20. The decorative layer 30 adhered to the above is provided.

The fireproof structural member 1 of the present embodiment is a pillar of a building, and as shown in FIGS. 1 and 2, the entire circumference of the load support portion 10 is covered with a burnout layer 20. Further, in the present embodiment, the load support portion 10, the burn-off layer 20, and the decorative layer 30 are all made of sugi wood, but the type of wood is not particularly limited. Further, the decorative layer 30 is not an essential component in the fireproof structural member of the present invention, and may be omitted. Hereinafter, each component of the fireproof structural member 1 will be described.

As shown in FIG. 1, the load support portion 10 is a wood-based material having a regular square columnar shape. As shown in FIG. 2, the load support portion 10 in the present embodiment is a structural laminated wood formed by laminating and adhering a plurality of wooden boards 13 having a rectangular cross section. That is, the fireproof structural member 1 according to the present embodiment is a fireproof laminated wood in which the load supporting portion 10 is made of laminated wood. The load support portion 10 is not limited to that made of such laminated lumber, and may be made of a single wooden board. Further, the cross-sectional shape orthogonal to the axis of the load supporting portion 10 is not limited to a square shape, and any shape can be used.

The non-burning layer 20 is a layer that prevents combustion or heat propagation to the load support portion 10 in the event of a fire in a building, and is composed of a plurality of flame-retardant wood-based materials 21 as shown in FIG. .. The flame-retardant-treated wood material 21 is made of, for example, a wood board that has been incombustible by impregnation with a phosphoric acid-based or boric acid-based flame retardant.

As shown in FIG. 2, the burn-off layer 20 is bonded so as to cover the surfaces of the plurality of inner flame-retardant wood-based materials 21A bonded to the surface 11 of the load-bearing portion 10 and the inner flame-retardant wood-based material 21A. It has a plurality of outer flame-retardant treated wood materials 21B and the like. That is, the burn-off layer 20 in the present embodiment is configured such that the flame-retardant wood-based material 21 has a multi-layer (two-layer) structure. As a result, even if combustion or heat tries to propagate from the decorative layer 30 side toward the load support portion 10 along the flame-retardant untreated material described later, the propagation path is complicated by complicating the load support portion. It is possible to prevent combustion and heat from propagating up to 10. The non-burning layer 20 is not limited to the two-layer structure as in the present embodiment, and may have a structure in which three or more layers of the flame-retardant wood-based material 21 are arranged, or the flame-retardant wood-based material 21 may be arranged. 21 may be a single-layer structure in which only one layer is arranged.

As shown in FIG. 2, the inner flame-retardant wood-based material 21A is fixed to the four surfaces 11 via an adhesive so as to cover the entire circumference of the load-bearing portion 10. Specifically, in the cross-sectional view of FIG. 2, two inner flame-retardant wood-based materials 21A are fixed to one surface 11 of the load support portion 10 via an adhesive. Further, at the four corners of the load-bearing portion 10, the surface of one inner flame-retardant-treated wood-based material 21A (the surface facing the load-bearing portion 10 side) is relative to the end face of another inner flame-retardant-treated wood-based material 21A adjacent thereto. Are butted together.

As the adhesive used for fixing the inner flame-retardant wood material 21A, for example, a thermosetting adhesive such as resorcinol resin or phenol resin can be used, but from the viewpoint of further enhancing the adhesive strength, the resorcinol resin adhesive It is preferable to use. However, this adhesive is not limited to a thermosetting adhesive, and any adhesive can be used.

In the cross-sectional view of FIG. 2, the case is not limited to the case where a plurality of inner flame-retardant wood-based materials 21A are fixed to one surface 11 of the load support portion 10, and one inner flame-retardant wood-based material is used. 21A may be fixed.

Similar to the inner flame-retardant treated wood material 21B, two outer flame-retardant treated wood materials 21B are provided for each surface 11 of the load supporting portion 10 in the cross-sectional view of FIG. At the four corners of the load bearing portion 10, the end face of one outer flame-retardant wood-based material 21B is abutted against the surface of another outer flame-retardant wood-based material 21B adjacent thereto. Further, the surface of the one outer flame-retardant treated wood material 21B is abutted against the surface and the end face of the inner flame-retardant treated wood material 21A. Then, at each of the four corners of the load supporting portion 10, the butt portion between the inner flame-retardant treated wood materials 21A and the butt portion between the outer flame-retardant treated wood materials 21B are in a state of being displaced from each other around the axis. There is. As a result, the path along the surface of the flame-retardant wood-based material 21 from the decorative layer 30 side to the load support portion 10 becomes intricate, and as described above, combustion and heat propagation to the load support portion 10 can be prevented. can.

The outer flame-retardant treated wood material 21B is adhered to the surface of the inner flame-retardant treated wood material 21A using, for example, an adhesive of resorcinol resin or phenol resin. The outer flame-retardant treated wood material 21B has basically the same configuration as the inner flame-retardant treated wood material 21A.

As shown in FIG. 2, the decorative layer 30 is provided so as to cover the entire circumference of the burn-off layer 20, and the surface thereof is decorated. The decorative layer 30 is made of untreated wood (flame retardant untreated material) that is not impregnated with a flame retardant.

Here, in a general fire-resistant structural member, the adhesive force of the flame-retardant-treated wood material (inner flame-retardant wood material) to the surface of the load-bearing portion may become a problem. Specifically, the adhesive used for adhering to the load-bearing part may have a poor affinity with the flame-retardant agent impregnated in the inner flame-retardant treated wood material, and due to this, the load-bearing part may have a poor affinity. It may be difficult to ensure sufficient adhesion of the inner flame-retardant wood-based material to the surface. In this case, in the event of a fire, the inner flame-retardant wood-based material may fall off from the surface of the load-bearing portion, making it difficult to reliably protect the load-bearing portion.

On the other hand, the flame-retardant treated wood material 21 according to the present embodiment improves the adhesive force to the surface 11 by adopting a structure in which the portion of the load supporting portion 10 in contact with the surface 11 is not impregnated with the flame retardant. , It is possible to prevent the surface 11 from falling off. Hereinafter, the configuration of the flame-retardant wood-based material 21 will be described in detail.

<Flame-retardant wood material>
FIG. 3 is a perspective view schematically showing the configuration of the flame-retardant treated wood material 21 (inner flame-retardant treated wood material 21A) according to the present embodiment. As shown in FIG. 3, the flame-retardant-treated wood material 21 is an inner layer material 25 composed of a plate-shaped core material 26 impregnated with a flame retardant and a single wood plate overlapping the core material 26 in the plate thickness direction. And an outer layer material 24 made of a single wooden board that sandwiches the core material 26 in the plate thickness direction together with the inner layer material 25.

The core material 26 has, for example, a plurality of (six sheets in this embodiment) wooden boards 27 (chemical-treated wooden boards) impregnated with a phosphoric acid-based or boric acid-based flame retardant, and these plurality of wooden boards 27 are boards. It is configured by overlapping in the thick direction and being thermally pressure-bonded to each other. The wooden boards 27 are thermally pressure-bonded to each other by a thermosetting adhesive (for example, an adhesive of resorcinol resin or phenol resin) applied to the surface of the boards. Each wooden board 27 has, for example, a rectangular shape and has the same size.

The number of wooden boards 27 constituting the core material 26 and the shape of the wooden boards 27 are not particularly limited and can be arbitrarily selected. The flame retardant impregnated in the wooden board 27 is not limited to phosphoric acid-based or boric acid-based ones.

As shown in FIG. 3, the inner layer material 25 constitutes one outermost layer in the plate thickness direction of the flame-retardant wood material 21, and is thermally pressure-bonded to the core material 26. Specifically, the inner layer material 25 has a rectangular shape having the same size as each wooden board 27 constituting the core material 26, and the first inner layer adhesive surface to be adhered to the surface 11 (FIG. 2) of the load support portion 10. It has 25A and a second inner layer adhesive surface 25B (a surface opposite to the first inner layer adhesive surface 25A) bonded to the core material 26. The first inner layer adhesive surface 25A is one of the outermost surfaces of the flame-retardant wood-based material 21 in the plate thickness direction. The inner layer material 25 is adhered to the core material 26 with a thermosetting adhesive such as resorcinol resin or phenol resin.

Here, the inner layer material 25 adhered to the surface 11 of the load supporting portion 10 is a flame-retardant untreated material (untreated wood board 28) that is not impregnated with the flame retardant. Therefore, as shown in FIG. 2, when the inner layer material 25 is adhered to the surface 11 of the load supporting portion 10, the problem of poor adhesion due to the poor affinity between the flame retardant and the adhesive as described above occurs. Hateful. Therefore, the flame-retardant wood-based material 21 can be reliably fixed to the surface 11 of the load-bearing portion 10 with only the adhesive. This makes it possible to prevent the flame-retardant wood-based material 21 from falling off from the surface 11 of the load-bearing portion 10, and the load-supporting portion 10 can be reliably protected by the flame-retardant wood-based material 21.

Here, the "flame-retardant untreated material" in the present embodiment means a solid wood, but is not limited thereto. For example, a material that is not impregnated with a flame retardant and contains a preservative or the like is also included in the "flame retardant untreated material" in the present invention. This also applies to the outer layer material 24 and the decorative layer 30.

In the present embodiment, the flame-retardant wood material 21 is fixed to the surface 11 of the load support portion 10 only with an adhesive, but unless it causes combustion or heat propagation to the load support portion 10. Fasteners such as screws and nails may be used together. These fasteners serve as a fail-safe in the event of insufficient adhesive strength.

The thickness (plate thickness) of the inner layer material 25 is smaller than the thickness of each wood board 27 constituting the core material 26, and is, for example, 0.5 mm or more and 10 mm or less. If the thickness of the inner layer material 25 is less than 0.5 mm, the flame retardant impregnated in the core material 26 may seep out to the outermost surface of the flame retardant treated wood material 21. On the other hand, when the thickness of the inner layer material 25 exceeds 10 mm, combustion propagates along the inner layer material 25 to the load support portion 10 at the abutting portion between the flame-retardant wood-based materials 21, and functions as a burn-off layer 20. May be hindered. From such a viewpoint, the thickness of the inner layer material 25 in the present embodiment is 0.5 mm or more and 10 mm or less, preferably 1.0 mm or more and 5.0 mm or less, and 1.5 mm or more and 3.0 mm or less. It is more preferably 2.0 mm or more and 3.0 mm or less. The thickness range of the inner layer material 25 defines a preferable range, and is not limited to this.

The outer layer material 24 constitutes the other outermost layer of the flame-retardant wood-based material 21 in the plate thickness direction, and is thermally pressure-bonded to the core material 26 in the same manner as the inner layer material 25. The outer layer material 24 has a rectangular shape having the same size as each wood board 27 constituting the core material 26 and the wood board constituting the inner layer material 25, and the first outer layer adhesive surface 24A bonded to the core material 26 and the opposite side thereof. Has a second outer layer adhesive surface 24B. The second outer layer adhesive surface 24B is the other outermost surface of the flame-retardant wood-based material 21 in the plate thickness direction. Further, the thickness of the outer layer material 24 is substantially the same as the thickness of the inner layer material 25.

The outer layer material 24 is adhered to the core material 26 with a thermosetting adhesive such as resorcinol resin or phenol resin. Further, as shown in FIG. 2, the outer layer material 24 of the inner flame-retardant treated wood material 21A is adhered to the inner layer material 25 of the outer flame-retardant treated wood material 21B by the above-mentioned adhesive. Further, the outer layer material 24 of the outer flame-retardant treated wood material 21B is adhered to the decorative layer 30 by the above-mentioned adhesive.

Like the inner layer material 25, the outer layer material 24 is a flame-retardant untreated material (untreated wood board 28) that is not impregnated with the flame retardant. Therefore, as in the case of the inner layer material 25, it is possible to obtain an effect of preventing poor adhesion due to poor affinity between the flame retardant and the adhesive. Specifically, in FIG. 2, the adhesive force of the outer flame-retardant treated wood material 21B to the surface of the inner flame-retardant treated wood material 21A and the adhesive force of the decorative layer 30 to the surface of the outer flame-retardant treated wood material 21B are secured. be able to.

Further, when the decorative layer 30 is omitted, the surface of the outer flame-retardant treated wood material 21B is exposed to the outside. Here, if the outer layer material 24 is not provided, the core material 26 impregnated with the flame retardant is exposed to the outside. In this case, the flame retardant may absorb moisture from the outside air and crystallize. On the other hand, by providing the outer layer material 24, it is possible to prevent the flame retardant from being exposed to the outside air and prevent the flame retardant from crystallizing as described above. However, in the flame-retardant wood-based material of the present invention, the outer layer material is not an essential component and can be omitted.

In the flame-retardant wood material 21 of the present embodiment, the plurality of wood boards are laminated and heated so that the fiber directions of the plurality of wood boards (wood boards constituting the inner layer material 25, the core material 26 and the outer layer material 24) are parallel to each other. It is a single plate laminated lumber (LVL; Laminated Veneer Lumber) constructed by pressure bonding. However, the flame-retardant wood material of the present invention is not limited to LVL, and may be, for example, plywood in which a plurality of wood boards are alternately laminated so that the fiber directions differ by 90 °, or lamina or. The inner layer material 25 and the outer layer material 24 may be attached to the front and back surfaces of a plate-shaped core material made of a particle board or the like by thermal pressure bonding, respectively.

Further, in the present embodiment, the case where both the inner layer material 25 and the outer layer material 24 are composed of one wooden board has been described, but the present invention is not limited to this. One or both of the inner layer material 25 and the outer layer material 24 may be composed of a plurality of wooden boards.

<Manufacturing method of fireproof structural members>
Next, a method for manufacturing the fireproof structural member 1 will be described. First, the regular square columnar load support portion 10 shown in FIGS. 1 and 2 is prepared (preparation step). Subsequently, the flame-retardant treated wood material 21 (inner flame-retardant treated wood material 21A and outer flame-retardant treated wood material 21B) is produced by the following procedure (production step).

First, the chemical-treated wood board 27 and the untreated wood board 28 are prepared (wood board preparation step). Specifically, first, the wooden board is cut into a rectangular shape of a predetermined size, and the cut wooden board is placed in a pouring can (not shown) filled with a phosphoric acid-based or boric acid-based flame retardant. do. Then, the pressurization and depressurization of the flame retardant are repeated in the injection can. As a result, the flame retardant agent is uniformly injected into the entire wooden board, and the chemical-treated wooden board 27 is obtained. On the other hand, the wood board not subjected to the impregnation treatment is used as the untreated wood board 28 in the following steps. In the present embodiment, six chemical-treated wood boards 27 and two untreated wood boards 28 are prepared for producing one flame-retardant treated wood material 21.

Next, the laminated body 90 is produced by stacking a plurality of chemical-treated wood boards 27 and a plurality of untreated wood boards 28 in the plate thickness direction and adhering the wood boards to each other with an adhesive applied to the board surface (). Laminating process). Specifically, first, the first untreated wood board 28 is placed on an arbitrary table (not shown). Then, the first chemical-treated wood board 27 having the adhesive applied to the surface of one of the boards is placed on the untreated wood board 28 with the adhesive facing downward. Next, an adhesive is applied to the surface of one of the second chemical-treated wooden boards 27, and the adhesive is placed on the first chemical-treated wooden board 27 with the adhesive facing downward. By repeating this procedure, the remaining four chemical-treated wood boards 27 are laminated in order.

Finally, an adhesive is applied to the surface of one of the second untreated wooden boards 28, and the adhesive is placed on the uppermost chemical-treated wooden board 27 with the adhesive facing downward. In this way, a laminated body 90 (FIG. 4) in which two untreated wood boards 28 are arranged so as to be the outermost layer of one and the other in the plate thickness direction is produced. The adhesive used in this laminating step is a thermosetting adhesive such as resorcinol resin or phenol resin. As shown in FIG. 3, two untreated wood boards 28 constitute an inner layer material 25 and an outer layer material 24, respectively, and six chemical-treated wood boards 27 form a core material 26.

Next, in a state where the laminated body 90 is heated, pressure is applied to the laminated body 90 in the plate thickness direction (heat pressure step). Specifically, as shown in FIG. 4, the laminated body 90 is arranged between the upper press portion 82 having a flat upper press surface 82A and the lower press portion 83 having a flat lower press surface 83A. .. Then, at least one of the upper press portion 82 and the lower press portion 83 is moved by the drive source shown in the figure so that the upper press surface 82A and the lower press surface 83A are close to each other. As a result, the laminated body 90 is pressed by the upper press surface 82A and the lower press surface 83A in the plate thickness direction. During this pressing, the laminated body 90 is heated at a predetermined temperature, so that the adhesive applied to the surface of the board is thermoset and the adjacent wooden boards are firmly adhered to each other.

In the thermal pressure step, the heating temperature of the laminated body 90 is preferably 80 to 180 ° C., preferably 100 to 180 ° C., from the viewpoint of curing the thermosetting adhesive in a shorter time to ensure reliable adhesion between the wooden boards. More preferably, it is 150 ° C. For the same reason, the press pressure is preferably 0.5 to 1.0 MPa, and the press time is preferably 10 to 30 minutes.

Next, in order to flatten the front and back surfaces of the laminated body 90, a cutting process is performed. As a result, the untreated wood board 28 becomes thinner than the chemical-treated wood board 27. The flame-retardant wood-based material 21 is produced by the above procedure.

Next, the flame-retardant wood-based material 21 is attached to the surface 11 of the load support portion 10 (attachment step). Specifically, an adhesive (resorcinol resin or phenol resin adhesive) is applied to the first inner layer adhesive surface 25A (FIG. 3) of the flame-retardant wood-based material 21, and the length direction of the flame-retardant wood-based material 21 is changed. The first inner layer adhesive surface 25A is attached to the surface 11 of the load support portion 10 in a state of being aligned with the length direction of the load support portion 10. Then, the flame-retardant wood-based material 21 is pressed against the surface 11 of the load support portion 10 by using a hydraulic press mechanism (not shown) or the like to perform compression tightening.

By continuing this compression state for a predetermined time, the adhesive is cured, whereby the flame-retardant treated wood material 21 (inner flame-retardant wood material 21A) is adhered to the surface 11 of the load support portion 10. Then, in the same procedure, the outer flame-retardant treated wood material 21B is adhered to the surface of the inner flame-retardant treated wood material 21A, and the decorative layer 30 is further adhered to the surface of the outer flame-retardant treated wood material 21B. The fireproof structural member 1 is manufactured by the above procedure.

The outline of the manufacturing method of the fireproof structural member which concerns on this embodiment is as follows. That is, this method produces a flame-retardant-treated wood material 21 in which a chemical-treated wood board 27 impregnated with a flame retardant and an untreated wood board 28 not impregnated with a flame retardant are laminated in the plate thickness direction. It has a process. This manufacturing step includes a wood board preparation step of preparing the chemical-treated wood board 27 and the untreated wood board 28, respectively, and the untreated wood board 28 and the chemical-treated wood board 27 so that the untreated wood board 28 becomes one of the outermost layers in the board thickness direction. In the laminating step of producing the laminated body 90 by laminating the wood boards in the plate thickness direction and adhering the wooden boards to each other with a heat-curable adhesive applied to the board surface, and the laminating body 90 in a heated state. It comprises a thermal pressure step of applying pressure to the body 90 in the plate thickness direction.

Further, this method includes a preparatory step of preparing the load supporting portion 10 and a sticking step of attaching the flame-retardant treated wood material 21 to the surface 11 of the load supporting portion 10. In the pasting step, the flame-retardant wood material 21 is pasted on the surface 11 of the load support portion 10 so that the untreated wood board 28 is adhered to the surface 11 of the load support portion 10 via an adhesive.

According to this method, a flame-retardant treated wood material 21 is obtained by impregnating a wooden board (veneer) with a flame retardant agent and then laminating and adhering the wooden boards to each other. Therefore, the flame retardant can be uniformly impregnated as compared with the case where the wooden boards are laminated and bonded to each other and then impregnated with the flame retardant. Moreover, since the wooden boards are bonded to each other by thermal pressure bonding using a thermosetting adhesive, it is possible to reliably bond the wooden boards to each other regardless of the affinity between the flame-retardant agent and the adhesive. ..

(Embodiment 2)
Next, the fireproof structural member 2 according to the second embodiment of the present invention will be described with reference to FIG. The fire-resistant structural member 2 basically has the same configuration as the fire-resistant structural member 1 according to the first embodiment and has the same effect, but the first embodiment is a beam of a building. It is different from the fireproof structural member 1. Hereinafter, only the differences from the first embodiment will be described.

As shown in FIG. 5, in the fireproof structural member 2, three of the four surfaces 11 of the load bearing portion 10 are covered with the inner flame-retardant wood-based material 21A, while the remaining one surface 11 is inside. Not covered with flame-retardant wood-based material 21A. That is, the one surface 11 is exposed to the outside. Further, the end faces of the inner flame-retardant treated wood material 21A and the outer flame-retardant treated wood material 21B are flush with the exposed surface 11 of the load supporting portion 10. Even in such a form, as in the case of the first embodiment, it is possible to sufficiently secure the adhesive force of the inner flame-retardant treated wood material 21A to the surface 11 of the load support portion 10.

(Other embodiments)
In the first and second embodiments, the fire-resistant laminated lumber whose load support portion 10 is made of laminated lumber (wood) has been described, but the fire-resistant structural member of the present invention is not limited to this. Like the fireproof structural member 3 shown in FIG. 6, a configuration in which the flame-retardant wood material 21 is adhered to the surface 11 of the load-bearing portion 10A made of, for example, a square steel pipe may be adopted. In this case, the flame-retardant wood material 21 can suppress the temperature rise of the load support portion 10A and suppress the thermal deformation of the load support portion 10A.

Further, as in the fireproof structural member 4 shown in FIG. 7, a configuration is adopted in which the flame retardant treated wood material 21 is adhered to the surface 11 of the load supporting portion 10B made of, for example, carbon fiber reinforced plastic (CFRP). May be done. In this case, similarly to the first and second embodiments, the flame-retardant treated wood material 21 can prevent the load supporting portion 10B from burning.

The following tests were conducted to confirm the effect of the present invention.

(Adhesive performance evaluation test)
First, a flame-retardant wood-based material (flame-retardant LVL) was produced by the following procedure. First, eight sugi veneers having a thickness of 3.8 mm were prepared as untreated wood boards. Then, by impregnating the six veneers of Sugi with a flame retardant (New Burnex S), six chemical-treated wooden boards were obtained (drug weight 250 kg, 300 kg).

Next, a laminate was prepared in which six chemical-treated wooden boards were sandwiched between two untreated wooden boards. At this time, as an adhesive for adhering the wooden boards to each other, the main agent (resorcinol resin, TW-28), the curing agent slurry (curing agent 30S for D), and the filler (hot P-2) are 100: 20: 10 to 13. Was used in the ratio of. Further, as the curing agent slurry, a mixture of the curing agent 30S for D and water so as to have a ratio of 9:11 was used.

The amount of the adhesive applied was 160 g / m ² or more, and the production time of the laminated body was 10 minutes or less. Then, the laminate was placed in a press device, and heat pressure was applied under the conditions of a heating temperature of 140 ° C., a press pressure of 0.8 MPa, and a pressurization time of 20 minutes. Then, the front and back surfaces (untreated wood board) of the laminate were ground so that the thickness of the laminate was 25 mm. A plurality of flame-retardant treated LVLs were produced by such a procedure.

Next, as shown in FIG. 2, the produced flame-retardant-treated LVL was adhered to the surface of a load-bearing portion made of a 120 mm square laminated lumber so as to have a two-layer structure. At this time, the secondary adhesive portion between the load support portion and the inner flame-retardant treated LVL (reference numeral “LS” in FIG. 2) and the secondary adhesive portion between the inner flame-retardant treated LVL and the outer flame-retardant treated LVL (in FIG. 2). As the reference numeral "LL"), an adhesive containing a main agent (TW-36) and a powdered curing agent (curing agent for D) in a ratio of 100:15 was used.

The amount of the adhesive applied was about 800 g / m ² , and the time from the start of application of the adhesive to the start of compression was within 20 minutes. Then, the flame-retardant LVL was pressed against the surface of the load-bearing portion at a pressure of 1 MPa overnight to perform compression, and a fire-resistant laminated wood was produced.

The produced refractory laminated lumber was subjected to a block shear test and a knife test, respectively. The block shear test was carried out by collecting test pieces including the secondary adhesive portions LS and LL in FIG. 2 in accordance with the Japanese Agricultural Standard (JAS) of the veneer laminated lumber. The knife test is performed by cutting out a 5 cm square test piece so as to include the secondary adhesive portions LS and LL, and confirming the xylem breaking rate (%) when the secondary adhesive portions LS and LL are forcibly peeled off. gone.

Further, as a comparative example, a flame retardant-treated LVL in which all eight veneers of Sugi were impregnated with a flame retardant was also produced. Then, this flame-retardant LVL was adhered to the surface of the load-bearing portion, and a block shear test and a knife test were performed in the same manner as in the above examples.

Table 1 shows the results of the block shear test and the knife test performed on the above-mentioned Examples and Comparative Examples for each drug treatment amount. The "adhesive layer surface" in Table 1 indicates the secondary adhesive portions LS and LL seen from the A1 direction in FIG. 2, and the "laminated surface" indicates the secondary adhesive portions LS and LL seen from the A2 direction. Each is shown.

As shown in Table 1, in Examples, improvement in shear strength was observed in any of the secondary bonded portions as compared with Comparative Examples. Further, in the case of the comparative example, there was a secondary adhesive portion in which the xylem breaking rate was less than 100% in both the block shear test and the knife test, whereas in the case of the example, all the secondary adhesive portions were present. The xylem breaking rate was 100% at the bonded portion. From this test result, by using a flame-retardant untreated wood board impregnated with a flame retardant for the secondary adhesive part (the adhesive part between the load support part and the flame-retardant treated LVL and the adhesive part between the flame-retardant LVLs). , It was found that the adhesive strength was improved.

(Fire resistance test)
First, a fire-resistant laminated lumber having a fire-resistant coating by a flame-retardant treatment LVL was produced in substantially the same manner as in the above-mentioned adhesive performance evaluation test. As the load-bearing portion, a structural sugi laminated wood having a size of 600 mm square and a height of 3300 mm was used. As the flame-retardant-treated LVL, two types of wood boards having untreated wood boards on both the front and back surfaces, having a thickness of 30 mm and a thickness of 35 mm, were produced in the same manner as in the above-mentioned adhesive performance evaluation test. Then, this flame-retardant LVL was adhered to the surface of the load support portion so as to have a two-layer structure. As the decorative layer, a Sugi KD material having a thickness of 5 mm was used. A resorcinol resin adhesive (TW-28) was used for the adhesion between the load supporting portion and the flame-retardant LVL, the adhesion between the flame-retardant LVLs, and the adhesion between the flame-retardant LVL and the decorative layer.

Next, using the prepared fire-resistant laminated wood, a fire-resistant performance test was conducted according to the following procedure. First, as shown in FIG. 8, the upper measurement position P1 850 mm away from the upper end of the fire-resistant laminated lumber, the intermediate measurement position P2 1650 mm away from the upper end, and the lower measurement position P3 850 mm away from the lower end of the fire-resistant laminated lumber, respectively. In, eight thermocouples were installed at equal intervals on the surface of the load support portion (24 in total). The numbers "1 to 24" in FIG. 8 indicate the thermocouples installed at each measurement position. Then, the refractory laminated wood in which the thermocouple was installed was placed in the furnace, and each of the four surfaces of the refractory laminated wood was heated for 60 minutes according to the heating temperature curve of ISO 834.

9 and 10 are graphs showing the temperature change at the upper measurement position P1, FIGS. 11 and 12 are graphs showing the temperature change at the intermediate measurement position P2, and FIGS. 13 and 14 are graphs showing the temperature change at the lower measurement position P3. It is a graph which shows the temperature change. The numbers assigned to each curve in the graphs of FIGS. 9 to 14 correspond to the thermocouple numbers in FIG. In each graph, the curve indicated by the number with "'" shows the result when the flame-retardant LVL with a thickness of 35 mm is used, and the curve indicated by the number without "'" is difficult with a thickness of 30 mm. The result when the fuel treatment LVL is used is shown.

In addition, as a comparative example, a fire-resistant laminated wood whose surface is covered with a flame-retardant treatment LVL impregnated with a flame retardant chemical on all eight veneers of Sugi was also produced, and a fire resistance performance test was conducted in the same manner. rice field. FIG. 15 is a graph showing the temperature change at the upper measurement position P1 of the comparative example, FIG. 16 is a graph showing the temperature change at the intermediate measurement position P2 of the comparative example, and FIG. 17 is a graph showing the temperature change at the lower measurement position P3 of the comparative example. It is a graph which shows the temperature change. The numbers assigned to each curve in the graphs of FIGS. 15 to 17 correspond to the thermocouple numbers in FIG. 8 in the same manner as described above.

Based on the graphs of FIGS. 9 to 17, it can be considered as follows. In FIGS. 15 to 17 of the comparative example, the tendency of the temperature change was different between the upper side, the middle side and the lower side, and the temperature rise was remarkable at the four corners of the load bearing portion (the temperature up to around 300 ° C. on the upper side and the lower side). Rose). On the other hand, in FIGS. 9 to 14 of the examples, the same tendency of temperature change is observed on the upper side, the middle side, and the lower side, and a remarkable temperature increase is observed at any position on the surface of the load bearing portion. There wasn't. Specifically, the average temperature at the four corners of the load bearing portion is 175 ° C. in the case of the flame-retardant treatment LVL having a thickness of 35 mm and about 200 ° C. in the case of the flame-retardant treatment LVL having a thickness of 30 mm. However, it was below the carbonization temperature of wood (about 210 to 260 ° C.). From this result, it was found that the 60-minute fire resistance can be realized by using the flame-retardant-treated LVL, which is the front and back layers of the untreated wood board not impregnated with the flame retardant, as the flame-retardant layer.

It should be understood that the embodiments and examples disclosed this time are exemplary in all respects and are not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1,2,3,4 Fireproof structural member 10,10A, 10B Load-bearing part 11 Surface 20 Stop-burning layer 21 Flame-retardant treated wood material 21A Inner flame-retardant treated wood material 21B Outer flame-retardant treated wood material 24 Outer layer material 25 Inner layer material 26 Core material 27 Wood board

Claims (5)

A flame-retardant wood-based material that adheres to the surface of the load-bearing part of a fire-resistant structural member.
A plate-shaped core material impregnated with a flame retardant and
It is composed of a wooden board including a first inner layer adhesive surface bonded to the surface of the load support portion and a second inner layer adhesive surface which is a surface opposite to the first inner layer adhesive surface, and is a plate with respect to the core material. The core material is provided with an inner layer material which is overlapped in the thickness direction and whose core material is thermally pressure-bonded to the second inner layer adhesive surface by a thermosetting adhesive.
The core material is attached to the load bearing portion via the inner layer material, and the core material is attached to the load support portion.
The inner layer material is a flame-retardant treated wood material, which is a flame-retardant untreated material not impregnated with the flame retardant agent. It is composed of a wooden board that sandwiches the core material in the plate thickness direction together with the inner layer material, and further includes an outer layer material that is thermally pressure-bonded to the core material with a thermosetting adhesive.
The flame-retardant treated wood material according to claim 1, wherein the outer layer material is a flame-retardant untreated material not impregnated with the flame retardant agent. The flame-retardant treated wood material according to claim 1 or 2, wherein the inner layer material has a thickness of 0.5 mm or more and 10 mm or less. The core material has a plurality of wooden boards impregnated with the flame retardant, and the plurality of wooden boards are overlapped in the plate thickness direction and are thermally pressure-bonded to each other by a thermosetting adhesive. The flame-retardant treated wood material according to any one of claims 1 to 3, wherein the wood material is characterized by the above. A fireproof structural member used as a structural member of a fireproof wooden building.
A load-bearing part that supports the load of a building and
A burn-off layer, which is adhered so as to cover the surface of the load-bearing portion and prevents combustion or heat propagation to the load-bearing portion, is provided.
A fireproof structural member, characterized in that the burn-off layer is made of the flame-retardant treated wood material according to any one of claims 1 to 4.

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