JP2009174286A - Fire-resistant wood structure member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wood structure member having fire-resistant performance which maintains the design of wood, and can be manufactured with a small number of processes. <P>SOLUTION: The fire-resistant wood structure member can be manufactured by mounting a fire-resistant wood covering material formed by overlaying chemically-treated woods or non-treated woods on each other so that their fiber directions are orthogonal and bonding them on a wood structure member by a simple method using wood screws and nails. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fire-resistant wooden structure member having a wood design and easy to manufacture.

  As a result of the 1998 revision of the Building Standards Law, it has become possible to build buildings of the same size and use as reinforced concrete structures if they meet the fire resistance specified in the law even in wooden structures. On the other hand, as a measure against global warming, the use of timber has been promoted to make the forest function as a carbon dioxide absorption source effective, and buildings are considered as a major application. In addition, with regard to buildings, the demand for environmental load has increased, and wooden buildings that consume less energy for construction are being reviewed.

  Under such circumstances, research and development regarding the provision of fire resistance to wooden structural members that expand the use of wooden buildings is being actively promoted. For example, Patent Document 1 and Patent Document 2 invent a thermally expandable fireproof covering material that imparts fireproof performance to a wooden structure member and a wooden structure member having fireproof performance using the same. In patent document 3, the wooden structure member which has the fireproof performance coat | covered with the material which plays the role of a coating | coated part and an insulation part around is invented. Further, in Non-Patent Documents 1 and 2, an attempt is made to impart fire resistance by covering a wooden structure member with a wooden material or the like in which a chemical is injected.

Patent Publication 9-256506 Patent Publication 2005-282360 Patent Publication 2007-46286 “Development of fire-resistant laminated wood (Part 3) Burn-stop of laminated wood pillars covered with aluminum tape and flame-retardant treated wood,” A-2, p87-88, 2007 "Development of wood fire-resistant structural members using cedar flame retardant plywood", Annual Meeting of Architectural Institute of Japan A-2, p97-98, 2007

  Wood structures, such as laminated timber used in buildings such as public facilities where many people gather, also serve as interior decorations, so wood design is regarded as important. In patent document 1 and patent document 2, since a heating foam sheet is covered on the whole surface of a wooden structure member, there exists a fault that the design of wood is lost.

  On the other hand, in Patent Document 3, it is assumed that the wood structure member is covered with a material having the role of an insulating portion and a covering portion, and the nonflammable liquid cancer-soaked wood is used for the covering portion of the outermost layer. It is possible to maintain the design of the wood. However, since a plurality of different materials are attached to the structural member, there is a drawback that the manufacturing process is increased and the productivity is deteriorated.

  Moreover, since the nonpatent literatures 1 and 2 coat | cover the wood material which carried out the chemical | medical agent treatment around the laminated material, the design of wood is hold | maintained. However, Non-Patent Document 1 is a method of alternately attaching aluminum tape and drug-treated wood to a wooden structure member, and Non-Patent Document 2 is a method of attaching three types of materials: untreated wood, drug-treated wood and gypsum board to a wooden structure member. In both cases, the number of work steps increases, and there are the same disadvantages as in Patent Document 3.

  The present invention solves the above-described problems in the prior art, and an object thereof is to provide a fire-resistant woody structural member that retains the design of wood and can be easily manufactured.

  The present invention is a fire-resistant wooden structural member characterized in that a wooden fire-resistant coating material composed of untreated wood or chemical-treated wood is attached by a simple method.

  Here, the invention described in claim 1 is characterized in that a wood fireproof covering material in which a plurality of chemical-treated wood or untreated wood are laminated and bonded so that the fiber directions are orthogonal to each other is used. By providing an adhesive layer in the coating material, cracks that occur in the coating material during heating can be suppressed, and the effect of preventing the progress of combustion can be obtained. The effect of suppressing and preventing the progress of combustion due to the opening of joints between the covering materials can be obtained.

  The invention described in claim 2 is characterized in that the chemical firewood is used in a portion of 12 to 24 mm from the side in contact with the wooden structural member. This chemical-treated wood layer can quickly stop the burning of the wood fireproof coating after the end of the fire and prevent the strength of the internal structural members from decreasing.

  In the invention of claim 3, the wood fireproof covering material is fixed to the wooden structure member using wood screws or nails, and the wood screws or nails are placed within the wood fireproof covering material to a position of 10 to 15 mm from the non-heated surface side. It is characterized by the structure of embedding and plugging. By embedding wood screws or nails in the wood fireproof covering, heat from the fire is not transmitted to the wood screws or nails, and the strength of the structural member can be prevented from being reduced.

  The invention according to claim 4 is characterized in that, in the wood fireproof covering material in the corner portion of the wood structure member, a wood screw or a nail is driven and fixed to the wood fireproof covering material in contact with the corner portion. In this way, even in the corners of wooden structures such as pillars or beams that rapidly progress in the event of a fire, the heat from the fire does not travel through the wood screws or nails, preventing a decrease in the strength of the wooden structures. Can do.

  In the present invention, the wooden structural member covering the wooden fireproof covering material is lumber, laminated lumber, LVL, etc., which can be used for pillars, beams, walls, ceilings and the like.

  In the present invention described in claim 1, various kinds of wood can be used as the chemical-treated wood, but cedar wood having good injectability is desirable from the viewpoint that the chemical can be uniformly injected into the wood.

  In the present invention according to claim 1, the chemicals used for the production of chemical-treated wood are diammonium hydrogen phosphate, monoammonium hydrogen phosphate, ammonium polyphosphate, monoguanidine phosphate, diguanidine phosphate, guanylurea phosphate, Examples include boric acid, borax, sodium octaborate, and ammonium bromide.

When chemicals mainly composed of diammonium hydrogen phosphate are used for chemical-treated wood, the amount injected into the wood is 180-220 kg of solid content per 1 m ³ of wood in order to quickly stop burning after the end of the fire. It is desirable to do.

  In the present invention according to claim 1, all tree species of the untreated wood are basically symmetric, but tree species such as larch and bay pine are more desirable because the wood burning rate becomes slower as the density of the tree species increases.

  In the present invention according to claim 1, the adhesive used for the wood fireproof coating material is resorcinol resin adhesive, resorcinol / phenol cocondensation resin adhesive, melamine resin adhesive, melamine / urea cocondensation resin adhesive, Examples thereof include molecular isocyanate-based adhesives. The carbonized layer formed by burning wood prevents heat and oxygen from being supplied to the uncarbonized part under the layer and has the effect of suppressing combustion. Therefore, a stronger carbonized layer is formed to suppress combustion. In order to enhance the effect, it is desirable to use a thermosetting adhesive such as a resorcinol resin adhesive or a resorcinol / phenol resin adhesive.

  The thickness of the wood fireproof covering material of the present invention according to claim 2 is to provide a heat shielding effect to prevent carbonization of internal structural members during a fire, and an effect to stop combustion in the covering material after the end of the fire. 60 mm or more is desirable.

  In the present invention according to claim 3, the wood screws, nails, etc. used for attaching the wood fireproof covering material have a length of 45 mm or more in order to fix the wood fireproof covering material to the structural member continuously after the end of the fire. Is desirable.

  In the present invention according to claim 3, the tree plug used for the hole formed for embedding the wood screw or the nail in the wood fireproof covering material can basically use all tree species, but the density and combustion of wood. Due to the speed relationship, a higher density tree species such as broadleaf trees such as Yachidamo is more desirable.

  The present invention is a fire-resistant wood structure member using a wood fire-resistant coating composed of chemical-treated wood or untreated wood, and can maintain the design of the wood even after the fire-resistant coating material is attached.

  The wood fireproof covering material used is integrated with an adhesive, and can be easily attached to a wood structure member using wood screws or nails, resulting in fewer work steps and improved productivity. .

  Hereinafter, examples of the present invention will be described based on actual fire resistance performance tests. The test assumed that the beam members were exposed to fire. As shown in FIGS. 1 and 2, the test body was prepared by attaching a wooden fireproof covering material 1 to one side and the bottom of the laminated material 2 and imitating a corner portion of a beam member.

  The specification of the wood fireproof covering material 1 used for the test is shown in FIG. In FIG. 3, only Comparative Example 2 has a single layer configuration, and the others have a multi-layer configuration in which wood having a thickness of 12 mm is laminated and bonded. The thickness of the wood fireproof covering material was 60 mm.

  Inventions 1 and 2 have a five-layer structure of untreated wood and drug-treated wood. In Invention 1, one layer on the side in contact with the laminated wood is a drug-treated wood, and in Invention 2 has two layers on the side in contact with the laminated wood. Was treated with drug-treated wood. In the comparative example, only untreated wood was used in comparative example 1, and only chemical treated wood was used in comparative examples 2-3.

The chemical-treated wood 5 in FIG. 3 is a cedar wood impregnated with 180 to 220 kg of solid content per m ^{3 of} diammonium hydrogen phosphate, which is a phosphate-based chemical. In the impregnation of cedar material, cedar material previously dried at 60 ° C. for 72 hours is submerged in an aqueous solution of diammonium hydrogenphosphate having a concentration of 24.0 to 26.4%, and the pressure is reduced using a reduced pressure injection device. Pressure was applied at 5 kPa for 30 minutes and at 1.2 MPa for 2 hours. The cedar wood after the injection treatment was dried to a water content of about 12% in a hot air circulating thermostat.

The multi-layered wood fire-resistant coating material excluding Comparative Example 2 was laminated and bonded so that the untreated wood or chemical-treated wood constituting it was perpendicular to the fiber direction. Adhesion of untreated wood or chemical treated wood was performed using a resorcinol resin adhesive under conditions of an application amount of 250 to 300 g / m ² , a pressing pressure of 690 kPa, and a pressing time of 24 hours.

  A wood screw 3 was used to attach the wood fireproof covering material 1 to the laminated material 2. The wood screw 3 had a length of 45 mm, and was buried in the wood fireproof covering material 1 up to a position of 15 mm from the non-heated surface, as shown in FIG. In addition, the wood fireproof covering material at the corner of the laminated lumber was fixed by driving the wood screw into the wood fireproof covering that touched at the corner.

  In the test, two surfaces on which the coating material of the test body was attached were heated for 1 hour assuming an actual fire, and then left for 6 hours with the heating stopped. The requirements for the fire resistance performance of the laminated wood are that the combustion stops within the standing time and that the laminated wood does not carbonize after the test. Table 1 shows the results of the test bodies using the coating materials of each specification.

  In the test body using Comparative Example 2 composed of a single layer of drug-treated wood, combustion did not stop within the standing time, and the laminated wood was carbonized after the test. On the other hand, the test body using Comparative Example 3 satisfied the requirements for fire resistance because the multilayer structure in which the fiber directions were orthogonal and bonded with a high heat resistant resorcinol resin adhesive suppressed combustion.

  In the test body using Comparative Example 1 composed only of untreated wood, the combustion reached the back surface of the wooden fireproof coating material within the standing time, and the coating material dropped and the laminated material burned.

  The test body using the present invention 1 or 2 in which one or two layers on the side in contact with the laminated wood are drug-treated wood has better performance than Comparative Example 1 because the drug-treated wood suppresses combustion, and fire resistance performance Met the requirements. At the same time, by using chemical treated wood, which is more expensive than untreated wood, only on the 12-24 mm side from the side in contact with the laminated wood, fire resistance performance can be obtained in the same manner as in Comparative Example 3 in which all layers are treated with chemical treated wood. Therefore, the use of chemical-treated wood is efficient.

  The remaining thickness of the coating material in the test bodies using the present inventions 1 and 2 was 17.3 to 22.6 mm for both the side surface portion and the bottom surface portion, and the wood screw was inside the remaining portion. In other words, by embedding wood screws up to 15 mm from the non-heated surface inside the coating material, the wood screws are kept at a temperature lower than the temperature at which the wood is carbonized. The carbonization of the material was prevented.

  The remaining thickness of the covering material at the corners in the test bodies using the present inventions 1 and 2 were 10.0 mm and 11.2 mm, and the combustion proceeded more than the other parts. However, at the corners, the wood screws that attach the covering material are driven into the covering materials that contact the corner portions, so that the carbonization of the laminated wood due to heat through the wood screws is prevented.

External view of test specimen for heating test showing one embodiment of the present invention AA line sectional view of the same test specimen for heating test in FIG. Construction of wood fireproof coating material used for the test specimen for the same heating test

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Wood fireproof covering material 2 ... Glued material 3 ... Wood screw 4 ... Wood plug 5 ... Chemical treatment wood 6 ... Untreated wood 7 ... Resorcinol resin adhesive adhesion layer

Claims (4)

  A fire-resistant wood structure member using a wood fire-resistant covering material in which chemical-treated wood or untreated wood is laminated and bonded so that fiber directions are orthogonal to each other.   The fire-resistant wooden structural member according to claim 1, wherein the wooden fire-resistant covering material uses chemical-treated wood in a portion of 12 to 24 mm from a side in contact with the wooden structural member.   The wood fireproof covering material is fixed to the wooden structure member using wood screws or nails, and the wood screw or nail is embedded in the wood fireproof covering material to a position of 10 to 15 mm from the side in contact with the wooden structure member and plugged. The fire-resistant woody structural member according to claim 1 or 2, characterized in that it has a constitution.   The fireproof wood structure member according to claim 1 or 2, wherein the wood fireproof covering material in the corner portion of the wooden structure member is configured to drive and fix a wood screw or a nail to the wood fireproof covering material in contact with the corner portion.

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