JP6497922B2 - Outer insulation and fireproof outer wall structure of wooden building - Google Patents

Description

  The present invention relates to a heat-insulated fire-resistant outer wall structure for a wooden building.

  Recently, there have been many studies on wooden refractory buildings. The reasons include the promotion of further use of timber under the initiative of the country, further spread of wooden buildings, and improvement of fire resistance of buildings from the viewpoint of disaster prevention due to earthquakes in urban areas.

  In order to construct a wooden fireproof building, it is required to make the outer walls, floors, beams, columns, roofs, and stairs, which are the main structural parts of the building, have a fireproof structure. In addition, when a fire breaks out, a wooden fireproof building is required to be self-supporting without falling down after the fire is extinguished.

  In order for the outer wall of a building to be recognized as a fireproof structure, it must pass a fireproof performance evaluation test. The evaluation test method is defined in JIS-A-1304. In the test method, heating from the outdoor side or heating from the indoor side is performed twice on the test piece of the outer wall structure. The heating conditions are specified in ISO-834, and the condition is that the temperature in the furnace in which the test body is installed is raised to about 950 ° C. over 1 hour, and then the heating is stopped and left as it is for 3 hours. It is.

  In a conventional fireproof outer wall structure of a wooden building, a structural member made of wood is covered with a noncombustible material so as not to be carbonized or ignited. In the fireproof outer wall structure, a nonflammable interior member is disposed on the indoor side of the structural member, and a nonflammable exterior member is disposed on the outdoor side. In particular, research and development has been conducted on exterior members. As a conventional fireproof outer wall structure of a wooden building, the structures described in Patent Document 1 and Patent Document 2 are known.

  Patent Document 1 discloses an exterior member provided on the outdoor side of a structural member made of wood. The exterior member is formed by laminating a first coating layer and a second coating layer installed on the outdoor side. The first covering layer is formed by pressing and joining a lightweight cellular concrete panel, and the second covering layer is formed by pressing and joining a calcium silicate plate. The joint portion of the lightweight cellular concrete panel and the joint portion of the calcium silicate plate are arranged so as not to overlap each other. In this outer wall structure, a so-called filled heat insulation method in which rock wool or the like is filled in a structural member is applied as a heat insulation method.

  Patent Document 2 discloses a fireproof outer wall structure of an outer-layer heat insulating method having heat insulating performance. The exterior member disclosed in Patent Document 2 discloses a structure in which one lath mortar layer, three slag gypsum plates, and two aluminum foil layers are laminated.

JP 2005-299194 A JP 2013-113033 A

  As an exterior member of the outer wall structure of a conventional wooden building, there are a structure in which a plurality of different types of materials are laminated and laminated, and a structure in which the same material is laminated and laminated together. In the outer wall structure of Patent Document 1, a lightweight cellular concrete panel and a calcium silicate plate are overlaid and the joint portions are shifted from each other. Further, in the outer wall structure of Patent Document 2, a lath mortar layer, a slag gypsum plate, and an aluminum foil layer are overlaid, and several kinds or a plurality of exterior members are overlaid.

  However, when several types of exterior members are present, procurement of materials and quality control become very laborious, leading to cost increase. Moreover, the number of man-hours increases and the construction period may be prolonged by constructing a plurality of exterior members. Furthermore, since the joint portions of the exterior member had to be shifted from each other, the design and construction were complicated and the construction period tended to be long.

  In addition, the case where the architectural style of the wooden building is an outer wall structure of a frame wall construction method will be described as an example. If there is a large temperature difference between the indoor side and the outdoor side, between the vertical frames of the frame assembly In a so-called filled thermal insulation specification in which a plurality of partitioned hollow regions are each filled with a heat insulating material, the heat insulating material is divided at the vertical frame portion, and the vertical frame portion becomes a thermal bridge. As a result, heat is easily transferred between the indoor side and the outdoor side, and there is a problem that the heat insulating performance is inferior. Therefore, it has been studied to adopt a heat insulation structure by so-called outer heat insulation in which the heat insulation performance is improved by continuously attaching the heat insulation material to the outdoor side of the frame assembly without dividing.

  The present invention solves the above-described problems of the prior art, and has excellent fireproof performance and heat insulation performance, and is easy to construct and low-cost for heat insulation of a wooden building. The purpose is to provide a structure.

In order to solve the above problems, the present invention relates to the following [1] to [6].
[1] A structural face member attached to the outdoor side of a structural member made of wood, and a phenol foam heat insulating plate attached to the outdoor side surface of the structural face member and having a thickness of 12 mm to 80 mm An aluminum foil layer located on the outdoor side surface of the phenol foam heat insulating plate, an incombustible trunk material attached to the outdoor side surface of the aluminum foil layer, and an outdoor side surface of the trunk material A lightweight aerated concrete panel attached to the light-weight aerated concrete panel, wherein the density of the lightweight aerated concrete panel is d (kg / m ³ ), the thickness of the lightweight aerated concrete panel is t (mm), and the strength of the lightweight aerated concrete panel is When the heat loss value is α (wt%), 200 ≦ d ≦ 550, 45 ≦ t ≦ 100, 5 ≦ α ≦ 15, and 3000 ≦ d × t ³ × α ÷ 100000 ≦ 3000 0 is satisfied.
[2] The outer heat insulating and fireproof outer wall structure of a wooden building according to [1], wherein d satisfies 250 ≦ d ≦ 400.
[3] The outer heat insulating and fireproof outer wall structure of a wooden building according to [1] or [2], wherein t satisfies 45 ≦ t ≦ 75.
[4] α is an outer heat insulating fireproof outer wall structure of a wooden building according to any one of [1] to [3], which satisfies 8 ≦ α ≦ 13.
[5] The external heat insulating fireproof outer wall structure of a wooden building according to any one of [1] to [4], wherein d, t, and α satisfy 5000 ≦ d × t ³ × α ÷ 100000 ≦ 15000.
[6] A heat insulating material is filled between the vertical frame and the vertical frame constituting the structural member, or between the pillar and the stud and the pillar and the pillar constituting the structural member. [5] The outer heat insulating fireproof outer wall structure of the wooden building according to any one of [5].

The outer wall structure described above includes a lightweight cellular concrete panel as an exterior member. Since this lightweight cellular concrete panel has the design parameters described above, sufficient panel strength is ensured, and it is possible to exhibit high fire resistance while suppressing an increase in panel weight. Since the increase in the panel weight is suppressed, the deterioration of workability and the earthquake resistance of the building is suppressed. Further, since the exterior member is a lightweight lightweight concrete panel, the work of shifting the joints from each other is not necessary.
Moreover, the phenol foam heat insulating board is attached to the outdoor side of the structural face material. According to this phenol foam heat insulating plate, since the phenol foam heat insulating plate is continuously attached to the structural face material without being divided, the heat insulating performance of the outer wall structure can be improved. Therefore, a fireproof outer wall structure for a wooden building having excellent fireproof performance and heat insulation performance, easy to construct and low cost is provided.

  Here, the relationship between the design parameters of the lightweight cellular concrete and the fire resistance performance will be described in detail. In order to construct the exterior member of the outer heat insulating fireproof outer wall structure of a wooden building with one layer of lightweight cellular concrete panel, the lightweight cellular concrete is considered in consideration of the following three parameters that are largely related to the fire performance of the lightweight cellular concrete panel. You need to design a panel. The three parameters are (1) the density of the lightweight cellular concrete panel, (2) the thickness of the lightweight cellular concrete panel, and (3) the amount of “water” that the lightweight cellular concrete has, that is, the lightweight cellular concrete. It is the amount of “water” that calcium silicate hydrate has.

  The present inventors have intensively studied what factors determine the fire resistance of lightweight cellular concrete panels. As a result of the study, the present inventors have found that the fire resistance performance of the lightweight cellular concrete panel is determined by the amount of “water” possessed by the lightweight cellular concrete. The “water” described here is “water” of the calcium silicate hydrate constituting the lightweight cellular concrete. In other words, it is “water” hydrated with calcium silicate. The fire resistance performance of the lightweight cellular concrete panel improves as the amount of “water” contained in the calcium silicate hydrate increases.

  Here, if the density of the lightweight cellular concrete panel is increased, the absolute amount of calcium silicate hydrate increases, so that the fire resistance performance is improved. On the other hand, if the density of the lightweight cellular concrete panel is reduced, the absolute amount of calcium silicate hydrate is reduced and the fire resistance performance is lowered. On the other hand, if the density is increased too much, the panel weight increases, so that the workability may decrease or the seismic performance may decrease due to an increase in the building weight. Moreover, if the density is too small, the physical strength of the lightweight cellular concrete panel may be insufficient.

  Further, if the thickness of the lightweight cellular concrete panel is increased, the absolute amount of calcium silicate hydrate increases, so that the fire resistance performance is improved. On the contrary, if the thickness is reduced, the absolute amount of calcium silicate hydrate is reduced, so that the fire resistance performance is lowered. On the other hand, if the thickness of the lightweight cellular concrete panel is increased too much, the panel weight increases, so that the workability may be deteriorated or the seismic performance may be deteriorated due to an increase in the building weight. Moreover, if the thickness is too thin, the physical strength of the lightweight cellular concrete panel may be insufficient.

  Moreover, if the quantity of the water which lightweight aerated concrete has, ie, the quantity of the water which the calcium silicate hydrate which comprises a lightweight aerated concrete panel increases, fireproof performance will improve. Conversely, when the amount of water contained in the calcium silicate hydrate decreases, the fire resistance performance decreases. However, it is difficult to actually obtain quantitatively the water of calcium silicate hydrate in lightweight cellular concrete. Therefore, in the present invention, the amount of water contained in the lightweight cellular concrete is defined as the amount of water contained in the lightweight cellular concrete by reducing the weight of the lightweight cellular concrete by heating. This value is defined as “ignition loss value”. Therefore, it can be said that the greater the ignition loss value, the higher the fire resistance.

  As described above, it is not appropriate to design the lightweight cellular concrete panel used for the outer wall structure considering only the ignition loss value deeply related to the fire resistance performance. That is, it is necessary to comprehensively evaluate the density, thickness, and ignition loss value of the lightweight cellular concrete panel while taking into account the panel strength and panel weight related to seismic performance and workability.

As a result of intensive studies on the above-described parameters of density, thickness, and ignition loss value, the present inventors have (1) a density d of 200 kg / m ^{3 to} 550 kg / m ³ and (2) thickness. The thickness t is 45 mm or more and 100 mm or less, (3) the ignition loss value α is 5 wt% or more and 15 t% or less, and d (kg / m ³ ) × t ³ (mm ³ ) × α (wt%) ÷ It was found that when the value of 100,000 is 3000 or more and 30000 or less, it is possible to satisfy the requirements for all of the panel weight, panel strength, and fire resistance.

  In the outer heat insulating fireproof outer wall structure of the wooden building of the present invention, an aluminum foil layer having a radiant heat reflection function is disposed on the outdoor side of the phenol foam heat insulating plate. Since the aluminum foil layer has a role of reducing heat transmitted to the structural member made of wood with respect to heating from the outdoors, carbonization and ignition of the structural member can be prevented.

  Further, in the outer heat insulating fireproof outer wall structure of the present invention, a trunk material is provided between the heat insulating material for outer heat insulation and the lightweight cellular concrete panel, but this outer material is incombustible. When the outer fireproof outer wall structure of the present invention is heated from the outside, the heat insulating material for the outer heat insulating shields the heat applied by the heating, and as a result, heat is generated in the ventilation layer in which the waist frame material is located. The inside of this ventilation layer becomes high temperature. Generally, a wooden building is made of a wood material. However, if the wooden material is used for the outer edge heat insulating structure of the present invention, the trunk material is ignited, resulting in carbonization of the structural member. May cause ignition. Therefore, in order to prevent carbonization and ignition of the structural member, the trunk material is made nonflammable.

  Further, in the outer heat insulating fireproof outer wall structure of the wooden building of the present invention, between the vertical frame and the vertical frame constituting the structural member, or between the pillar and the stud and the stud and the stud constituting the structural member, It is preferable that the heat insulating material is filled. With such a configuration, better heat insulation performance can be obtained.

  The `` wooden building '' described here is a general term for buildings in which main structural members such as pillars, beams, girders, etc. are made of wood, and the construction method of the building is a wooden frame wall method, a wooden frame wall method, etc. Any construction method is acceptable. “Wood” refers to a wooden material, and includes a woody material formed by processing wood fibers. The “structural member” refers to a main part that supports the load and external force of a building, such as a frame member (a beam, a column, a brace, etc.) of a wooden frame structure method or a frame structure of a wooden frame wall method.

  The terms “fireproof structure” and “fireproof performance” used in this specification are synonymous with those defined in Article 2 of the Building Standards Act and Article 107 of the Building Standards Act Enforcement Ordinance.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the external heat insulation fireproof outer wall structure of the wooden building which has the outstanding fireproof performance and heat insulation performance, is easy to construct, and is low-cost.

FIG. 1 is a perspective view of a wooden building according to an embodiment of the present invention, with a part of the outer heat insulating fireproof outer wall structure cut out. FIG. 2 is a horizontal cross-sectional view showing an outer heat insulating and fireproof outer wall structure of a wooden building according to an embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of an outer heat insulating fireproof outer wall structure of a wooden building according to the present invention will be described in detail with reference to the drawings.
In addition, this embodiment demonstrates using the example which applied the outer-layer heat insulation fireproof outer wall structure to the frame structure which is a structural member of a wooden frame wall construction method. FIG. 1 is a perspective view showing a part of an outer heat insulating fireproof outer wall structure according to an embodiment of the present invention. FIG. 2 is a horizontal cross-sectional view showing an outer heat insulating fireproof outer wall structure according to an embodiment of the present invention.

<Outer heat insulation fireproof outer wall structure 1>
As shown in FIG. 1 and FIG. 2, the outer heat insulating and fireproof outer wall structure 1 according to the present embodiment is a wall body that partitions the indoor and the outdoor of a building, and adopts a structure used for a framed wall construction method. . The outer heat insulating fireproof outer wall structure 1 mainly includes a structural member 2, an interior member 3 provided on the indoor side of the structural member 2, a heat insulating plate member 4 provided on the outdoor side of the structural member 2, and a heat insulating plate member 4. The exterior member 5 provided on the outdoor side.

<Structural member 2>
The structural member 2 is a member that becomes a skeleton of the wall body, and supports the load and external force of the building. As shown in FIG. 1, the structural member 2 includes a plurality of vertical frame members 21, an upper frame member 22 that connects upper ends of the plurality of vertical frame members 21, and lower ends of the plurality of vertical frame members 21. And a lower frame member 23 for connecting them together. A structural face member 24 is attached to the frame member 21 on the outdoor surface of the structural member 2.

  The vertical frame member 21, the upper frame member 22, and the lower frame member 23 are all long wooden members having a cross-sectional dimension of, for example, 38 mm × 89 mm, which are known as wood for a frame wall construction method. Etc. are fixed to each other. The vertical frame members 21 are erected at equal intervals with an interval of 455 mm or less in the horizontal direction.

  The structural face member 24 is fixed to the frame composed of the vertical frame member 21, the upper frame member 22, and the lower frame member 23 by nailing, and is provided on the outdoor side with respect to the frame. Thus, the performance as the structural member 2 is exhibited by integrating the vertical frame member 21, the upper frame member 22, the lower frame member 23, and the structural face member 24.

As the structural face material 24, for example, a structural plywood conforming to the Japanese Agricultural Standard having a thickness of 9 mm and a density of 0.55 g / cm ³ can be used. Further, as the structural face material 24, for example, a structural plywood having a thickness of 9 mm or more, a structural panel having a thickness of 9 mm or more, a particle board having a thickness of 9 mm or more, a shising board having a thickness of 12 mm or more, etc. Wood board, hard wood cement board with a thickness of 12mm to 25mm, pulp cement board with a thickness of 9mm or more, flexible board with a thickness of 9mm or more, calcium silicate board with a thickness of 9mm or more, thickness A volcanic glassy multilayer board of 9 mm or more, or a gypsum board having a thickness of 12 mm or more can be used.

<Filling insulation 25>
Since the architectural style of the outer heat insulating and fireproof outer wall structure 1 is a wooden framed wall construction method, a filling heat insulating material 25 may be arranged between the adjacent frame materials 21 in order to further improve the heat insulating performance of the building. As the filling heat insulating material 25, for example, glass wool having a density of 24 kg / m ³ or rock wool can be used. In addition, when the architectural style of the outer heat insulating fireproof outer wall structure 1 is a wooden frame construction method, a filling heat insulating material may be disposed between the columns and the intercolumns and between the columns and the intercolumns.

<Interior member 3>
The interior member 3 constitutes a wall surface on the indoor side of the wall body, and protects the structural member 2 from a flame such as a fire generated indoors. The interior member 3 includes an interior underlayer 31 made of reinforced gypsum board attached to the indoor side of the structural member 2 and an interior overcoat layer 32 made of reinforced gypsum board laminated on the indoor side of the interior underlayer 31. doing.

  The interior underlayer 31 is configured by abutting and joining the small edge surfaces of a plurality of reinforced gypsum boards to each other. The interior underlayer 31 is fixed to the structural member 2 with a gypsum board nail.

  The interior overlying layer 32 is configured by butting and joining the small edge surfaces of a plurality of reinforced gypsum boards. The interior upper layer 32 is fixed to the structural member 2 by a gypsum board nail penetrating the interior underlayer 31.

  These reinforced gypsum boards preferably have a thickness of 21 mm or more and a bulk specific gravity of 0.75 or more. According to such a reinforced gypsum board, the water in the reinforced gypsum board is vaporized by the heat of the fire when a fire occurs indoors, so it is possible to consume the heat of the fire and delay the transfer of heat. . Therefore, carbonization and ignition of the structural member 2 can be prevented, and fire resistance against heat from the indoor side can be ensured. The interior member 3 may have an aluminum foil that is sandwiched between the interior underlayer 31 and the interior overlayer 32.

<Insulation plate 4>
The heat insulating plate 4 is a member having heat insulating performance used in the outer heat insulating construction method, and imparts excellent heat insulating performance to the outer heat insulating fireproof outer wall structure 1. The heat insulating plate 4 is provided on the surface on the outdoor side of the structural face member 24. The heat insulating plate 4 is affixed to the outdoor side of the structural face 24 using a tape or an adhesive. As the heat insulating plate material 4, a phenol foam heat insulating plate 41 according to JIS A 9511 can be used. The thickness of the phenol foam heat insulating plate 41 is not less than 12 mm and not more than 80 mm, preferably not less than 20 mm and not more than 60 mm, more preferably not less than 20 mm and not more than 40 mm. When the thickness of the phenol foam heat insulating plate 41 is less than 12 mm, excellent heat insulation performance cannot be imparted. When the thickness of the phenol foam heat insulating plate 41 exceeds 80 mm, the wall thickness increases, which is not practical.

<Exterior member 5>
The exterior member 5 is a member that constitutes a wall surface on the outdoor side of the wall body, and protects the structural member 2 from flames such as a fire that occurs outdoors. The exterior member 5 includes an aluminum foil layer 51 disposed on the outdoor surface of the heat insulating plate 4, a waterproof layer 52 disposed on the outdoor surface of the aluminum foil layer 51, and an outdoor surface of the waterproof layer 52. The air-permeable layer 53 is positioned, and the lightweight cellular concrete panel layer 54 is located on the outdoor side of the air-permeable layer 53.

  The aluminum foil layer 51 is made of aluminum foil, and is affixed to the outdoor side of the heat insulating plate 4 with an adhesive, tape, staple, or the like. As the aluminum foil used in the aluminum foil layer 51, one conforming to JIS H 4160 is preferably used. The seam of the aluminum foil of the aluminum foil layer 51 is preferably overlapped by 90 mm or more in both length and width. The aluminum foil of the aluminum foil layer 51 has a radiant heat reflection function and has a role of reducing heat transmitted to the structural member 2 by heating from the outside, and therefore prevents carbonization and ignition of the structural member 2. Can do.

  The waterproof layer 52 protects the structural member 2 and the heat insulating plate material 4 from rain water or the like that has penetrated from the gap between the exterior members 5, and is adhered to the outdoor surface of the aluminum foil layer 51 with an adhesive, tape, staple, or the like. It has been. As the waterproof layer 52, an asphalt felt according to JIS A 6006 or a moisture-permeable waterproof sheet according to JIS A 6111 is preferably used.

  The ventilation layer 53 is formed by installing a plurality of incombustible body edge members 53a at predetermined intervals in the horizontal direction on the outdoor side of the waterproof layer 52. The thickness of the trunk edge material 53a is preferably 10 mm or more and 25 mm or less. The trunk edge member 53a is an elongated thin plate-like member having a cross-sectional dimension of 90 mm, for example. By this edge material 53a, it communicates from the lower end part of the exterior member 5 to the upper end part between the nonflammable case edge material 53a between the waterproof layer 52 and the lightweight cellular concrete panel layer 54 and adjacent to each other. A space is formed. Since air flows vertically through this space, corrosion of the structural member 2 due to moisture can be prevented. The nonflammable trunk edge material 53a is fixed to the structural member 2 by passing a nail, a screw, or the like through the trunk edge material 53a, the waterproof layer 52, the aluminum foil layer 51, and the heat insulating plate material 4.

  As the incombustible body edge material 53a, it is preferable to use a hard wood chip cement plate, a high-pressure wood wool cement plate, a square steel pipe, a lip groove steel pipe, an I-shaped steel, a grooved steel, or an H-shaped steel.

  The lightweight cellular concrete panel layer 54 is configured by a plurality of lightweight cellular concrete panels 55 being pressed against and joined to the outdoor side surface of the trunk edge material 53a. The lightweight cellular concrete panel 55 is a plate-like panel.

  The lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54 is a panel formed into a plate shape, and has excellent characteristics such as light weight, high heat insulation, high workability, and high fire resistance. Therefore, lightweight cellular concrete panels are used in many buildings in a wide range of fields, from high-rise buildings to ordinary houses. For example, lightweight cellular concrete panels are used in parts such as outer walls, partitions, floors, and roofs. In the lightweight cellular concrete panel, a slurry obtained by mixing a siliceous raw material, a calcareous raw material, water, a foaming agent, and the like is poured into a mold to foam the mixture. Subsequently, the semi-cured mixture is obtained by curing at high temperature and high pressure steam in an autoclave.

The lightweight cellular concrete panel 55 has a density d of 200 kg / m ³ or more and 550 kg / m ³ or less, a thickness t of 45 mm or more and 100 mm or less, and an ignition loss value α of 5 wt% or more and 15 wt% or less. It is. The value of d × t ³ × α ÷ 100,000 is 3000 or more and 30000 or less. If the lightweight cellular concrete panel 55 satisfying such parameters is used, it is possible to prevent the structural member 2 from being carbonized or ignited against a fire from the outside.

  It is preferable that the lightweight cellular concrete panel 55 has a reinforcing reinforcing bar and a reinforcing wire mesh embedded therein. Here, the reinforcing reinforcing bars are obtained by arranging reinforcing bars in a desired shape and welding the crossing contacts. The reinforcing wire mesh is obtained by processing iron into a net shape, and a lath mesh or the like is a typical example of the reinforcing wire mesh. The shape, size, thickness of the reinforcing bar, size of the mesh of the reinforcing mesh, etc. are not limited. In addition, it is preferable that the reinforcing reinforcing bar or the reinforcing wire mesh is subjected to a rust preventive treatment effective for durability. A known synthetic resin material or the like can be used as the rust preventive material.

  As the density d of the lightweight cellular concrete panel 55 is larger, the absolute amount of calcium silicate hydrate constituting the lightweight cellular concrete increases, and the fire resistance performance is improved. However, the panel weight increases as the density d of the lightweight cellular concrete panel 55 increases. According to the increase in the panel weight, the workability is reduced, the building weight is increased, the seismic performance is reduced, and the raw material for manufacturing the lightweight cellular concrete panel 55 is increased, so that the manufacturing cost is increased. Cases can arise.

  On the other hand, the lower the density d of the lightweight cellular concrete panel 55, the lighter the panel weight. Therefore, there are advantages that workability is improved, earthquake resistance is improved by reducing the weight of the building, and raw materials for manufacturing the lightweight cellular concrete panel 55 are reduced, thereby reducing manufacturing costs. However, as the density d of the lightweight cellular concrete panel 55 is lower, the absolute amount of calcium silicate is reduced, so that fire resistance may be lowered or panel strength may be lowered.

Accordingly, as a result of intensive studies, the inventors have determined that the density d of the lightweight cellular concrete panel 55 is 200 kg / m ³ or more and 550 kg / m ³ or less, preferably 230 kg / m ³ or more and 500 kg / m ^3. It has been found that it is not less than 250 kg / m ³ and more preferably not more than 400 kg / m ³ . Here, when the density d is less than 200 kg / m ³ , the panel strength is low and the fire resistance is low, which is not practical. On the other hand, if the density d exceeds 550 kg / m ³ , the panel weight increases and the workability decreases, and the building weight increases and the seismic performance decreases, which is not practical.

  Further, as the thickness t of the lightweight cellular concrete panel 55 is increased, the absolute amount of calcium silicate hydrate constituting the lightweight cellular concrete panel 55 is increased and the fire resistance is improved. However, the greater the thickness t of the lightweight cellular concrete panel 55, the greater the panel weight. According to the increase in the panel weight, the workability is reduced, the building weight is increased, the seismic performance is lowered, and the raw material for producing the lightweight cellular concrete panel 55 is increased, so that the manufacturing cost is increased. Cases can arise.

  On the other hand, the smaller the thickness t of the lightweight cellular concrete panel 55, the lighter the panel weight. According to the weight reduction of the panel weight, the workability is improved, the building weight is lightened, the earthquake resistance is improved, and the raw material for producing the lightweight cellular concrete panel 55 is reduced, so that the manufacturing cost is reduced. There are benefits. However, the smaller the thickness t of the lightweight cellular concrete panel 55, the lower the absolute amount of calcium silicate hydrate, and the fire resistance may be reduced.

  Therefore, as a result of intensive studies, the inventors have determined that the range of the thickness t of the lightweight cellular concrete panel 55 is 45 mm or more and 100 mm or less, preferably 45 mm or more and 80 mm or less, more preferably 45 mm or more and 75 mm or less. I found out. Here, when the thickness t is less than 45 mm, the fire resistance is low, which is not practical. On the other hand, when the thickness t exceeds 100 mm, the workability deteriorates and is not practical.

  Moreover, the fire resistance of the lightweight cellular concrete panel 55 is higher as the ignition loss value α of the lightweight cellular concrete panel 55 is larger. That is, when the ignition loss value α is large, the amount of water that the lightweight cellular concrete panel 55 has, that is, the “water” that the calcium silicate hydrate constituting the lightweight cellular concrete has is large in the lightweight cellular concrete. It is because it is doing. However, since the production of the lightweight cellular concrete panel 55 containing a large amount of calcium silicate hydrate is technically difficult, there is an upper limit to the amount of calcium silicate hydrate that can be present in the lightweight cellular concrete. On the other hand, the smaller the ignition loss value α, the lower the fireproof performance of the lightweight cellular concrete panel 55.

  Therefore, as a result of intensive studies, the present inventors have found that the range of the ignition loss value α of the lightweight cellular concrete panel 55 is 5 wt% or more and 15 wt% or less, preferably 7 wt% or more and 14 wt% or less, more preferably Was found to be 8 wt% or more and 13 wt% or less. Here, when the ignition loss value α is less than 5 wt%, the fire resistance is low, so that the fire resistance required for the outer heat insulating fire resistant outer wall structure 1 cannot be satisfied.

However, in order to satisfy all of the panel weight, panel strength, and fire resistance required for the lightweight cellular concrete panel 55, the lightweight cellular concrete panel 55 has the above three parameters: (1) density d (kg / M ³ ), (2) thickness t (mm), and (3) ignition loss value α (wt%) may be insufficient even in the above numerical range.

  For example, even if the density d, the thickness t, and the ignition loss value α are within the above numerical range, the lightweight cellular concrete having the density d and the thickness t close to the upper limit of the numerical range. The panel 55 satisfies the fire resistance performance, but the panel weight increases, so that the workability is lowered and may not be practical.

  Moreover, although the density d is in the above numerical range, the lightweight cellular concrete panel 55 in which the density d is close to the lower limit of the numerical range may not satisfy the fire resistance. In that case, it is necessary to increase the thickness t of the lightweight cellular concrete panel 55 or the ignition loss value α.

Therefore, in order to satisfy all of the panel weight, panel strength, and fire resistance required for the lightweight cellular concrete panel 55, it is necessary to comprehensively evaluate the above three parameters. As a result of intensive studies on the evaluation method, the present inventors have conducted a new study of density d (kg / m ³ ) × (thickness t) ³ (mm ³ ) × ignition loss value α (wt%) ÷ 100,000. We found that it can be evaluated by parameters.

When the value of new parameter d × t ³ × α ÷ 100,000 is 3000 or more and 30000 or less, preferably 4000 or more and 25000 or less, more preferably 5000 or more and 15000 or less, It has been found that the panel strength and fire resistance can be suitably satisfied.

  According to the outer heat insulating fireproof outer wall structure 1 including the lightweight cellular concrete panel 55, it is possible to satisfy the panel weight, the panel strength, and the fireproof performance required for the lightweight cellular concrete panel 55 in a balanced manner. Therefore, the exterior member 5 can be composed of only one kind of material and a single exterior member, that is, the lightweight cellular concrete panel 55. For this reason, the construction is simple and low-cost outer heat insulating fireproof outer wall structure 1 can be realized. For example, according to the outer heat insulating fireproof outer wall structure 1, after heating for 1 hour under the heating conditions specified by ISO-834 from the outdoor side or indoor side, the heating is stopped and left for 3 hours. It has been confirmed that no carbonization or ignition is observed on the member. And according to the outer-layer heat insulation fireproof outer wall structure 1, it becomes possible to build a wooden fireproof building easily, and the greater spread of wooden construction can be aimed at.

  Further, the outer heat insulating fireproof outer wall structure 1 has a double-structured interior member 3 formed by laminating an interior underlayer 31 and an interior overlayer 32 on the indoor side of a structural member 2 made of wood. ing. According to the interior member 3, it is possible to reduce the heat of the fire transmitted to the structural member 2 made of wood with respect to a fire from the inside, and to prevent carbonization and ignition of the structural member 2.

  Next, the Example at the time of performing a fireproof performance evaluation test is demonstrated using the outer-layer heat insulation fireproof outer wall structure 1 shown by FIG.1 and FIG.2. In addition, this invention is not limited to the specific dimension illustrated by a following example.

  First, the outer heat insulating fireproof outer wall structure 1 will be described in detail. The outer heat insulating fireproof outer wall structure 1 is composed of a structural member 2, an interior member 3, a heat insulating plate material 4 and an exterior member 5, and adopts a structure used in a wooden frame wall construction method.

<Structural member 2>
As shown in FIG. 1, the structural member 2 includes a plurality of vertical frame members 21, an upper frame member 22 that connects upper ends of the plurality of vertical frame members 21, and lower ends of the plurality of vertical frame members 21. A lower frame member 23 that connects the two members to each other and a structural surface member 24 that is attached to the surface of the vertical frame member 21 on the outdoor side are configured. The vertical frame member 21, the upper frame member 22, and the lower frame member 23 are long wooden members each having a cross-sectional dimension of 38 mm × 89 mm used as wood for the frame wall construction method. The vertical frame member 21, the upper frame member 22, and the lower frame member 23 were fastened to each other with screws. The vertical frame material 21 was erected at an equal interval of 455 mm. As the structural face material 24, a structural plywood having a thickness of 9 mm was used. The structural surface material 24 was fixed to the vertical frame material 21, the upper frame material 22, and the lower frame material 23 by driving nails into the surface of the vertical frame material 21 on the outdoor side.

<Interior member 3>
The interior member 3 has a reinforcing gypsum board having a thickness of 21 mm which is an interior underlayer 31 on the indoor side of the structural member 2 and a thickness which is an interior upper layer 32 positioned on the indoor side of the interior underlayer 31. Is composed of a two-layer structure in which a 21 mm reinforced gypsum board is laminated. The interior underlayer 31 is configured by joining a plurality of reinforced gypsum boards together and joining them. The interior underlayer 31 was struck to the structural member 2 with a gypsum board nail. The interior overlying layer 32 is configured by a plurality of reinforced gypsum boards being butted together and joined together. The interior upper layer 32 was struck to the structural member 2 by passing a nail through the interior upper layer 32 and the interior underlayer 31. Moreover, the joint agent for gypsum boards according to JIS A 6914 was applied to the joint portion of the interior overlying layer 32 as a joint agent for interior material, and finished smoothly.

<Insulation plate 4>
The heat insulating plate 4 is made by attaching a plurality of phenol foam heat insulating plates 41 (manufacturer: Asahi Kasei Construction Materials Co., Ltd., product name: Neomafoam) with a thickness of 35 mm to each other and bonding the tape to the outdoor side surface of the structural face material 24. Used to fix and configure. A special tape was applied to the vertical and horizontal joints of the phenol foam heat insulating plate 41.

<Exterior member 5>
The exterior member 5 is disposed on the outdoor side of the aluminum foil layer 51, the waterproof layer 52 disposed on the outdoor surface of the aluminum foil layer 51, and the outdoor side of the waterproof layer 52. The air-permeable layer 53 and a lightweight cellular concrete panel layer 54 located on the outdoor side of the air-permeable layer 53 are provided.

  The aluminum foil layer 51 was an aluminum foil having a thickness of 30 μm according to JIS H 4160, and was attached to the outdoor side of the heat insulating plate 4 with a tape. The seam of the aluminum foil was overlapped at 90 mm both vertically and horizontally. The waterproof layer 52 is a moisture permeable waterproof sheet (manufacturer: Asahi, Deyupon, Flash, Span Product Co., Ltd., trade name: Tyvek), and was attached to the outdoor side of the aluminum foil layer 51 using staples. The seam of the moisture permeable waterproof sheet was overlapped at 90 mm both vertically and horizontally.

  The ventilation layer 53 was formed on the outdoor side of the waterproof layer 52 by placing a plurality of incombustible body rim materials 53a against the structural face material 24 with screws at a predetermined interval in the horizontal direction. The nonflammable trunk edge material 53a is a thin and thin plate-like member obtained by cutting a hard-wood piece cement board (manufacturer: Nichiha Co., Ltd., trade name: Century fireproof ground board) into a cross-sectional dimension of 18 mm × 90 mm. The lightweight cellular concrete panel layer 54 was configured by pressing and joining a plurality of lightweight cellular concrete panels 55. The lightweight cellular concrete panel 55 is made by passing a screw through the lightweight cellular concrete panel 55, the incombustible trunk edge material 53a, the waterproof layer 52, the aluminum foil layer 51, and the phenol foam heat insulating plate 41 and hitting the structural member 2. Fixed. Further, an acrylic sealing material was applied to the joint portion of the lightweight cellular concrete panel layer 54.

  The outer wall structure 1 of the present example was constituted by the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5.

  Next, the measurement method of each value about the lightweight cellular concrete panel 55 and the fire resistance evaluation test method of the outer wall structure 1 will be described.

<Density of lightweight cellular concrete panel>
The lightweight cellular concrete panel 55 was cut out as a block having a size of 100 (mm) × 100 (mm) × 40 (mm), and the block was dried with a dryer at 105 ° C. until reaching a constant weight. The weight W (kg) after the drying and the volume V (m ³ ) of the block are measured, and the density d is calculated by the equation (1).
d (kg / m ³ ) = W / V (1)

<Thickness t of lightweight cellular concrete panel>
The thickness t was measured in units of 1 mm with a caliper.

<Light loss value α of lightweight cellular concrete panel>
The lightweight cellular concrete was pulverized until it became powdery. The powder was dried with a dryer at 105 ° C. until a constant weight was reached. The weight after drying is defined as A (g). Next, the powder which became the constant weight was heated for 1 hour using the electric furnace of 1000 degreeC. And the weight after a heating is measured and let the weight be B (g). The ignition loss value α is calculated by the equation (2).
α (wt%) = (A−B) × 100 / B (2)

<Moisture content β of lightweight cellular concrete panel>
The lightweight cellular concrete panel 55 is cut out as a block having a size of 600 (mm) × 600 (mm) × 40 (mm), and the weight C (kg) of the block is measured. The block was dried with a dryer at 105 ° C. until a constant weight was reached. The dried weight D (kg) is measured. The moisture content β of the lightweight cellular concrete panel is calculated by the equation (3).
β (wt%) = (C−D) × 100 / D (3)

<Evaluation method of fireproof performance of outer heat insulating fireproof outer wall structure>
The test body of the outer heat insulating fireproof outer wall structure 1 is heated from the outdoors or indoors for 1 hour according to the heating curve defined in ISO-834, and then the heating is stopped and left as it is for 3 hours. Thereafter, the test body is disassembled, and the structural member 2 is visually inspected for carbonization and ignition.

Example 1
In Example 1, fire resistance performance evaluation of the outer-layer heat insulation outer wall structure 1 comprised by the structural member 2, the interior member 3, the heat insulation board | plate material 4, and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 375 (kg / m ³ )
t = 50 (mm)
α = 11.5 (wt%)
d × t ³ × α ÷ 100000 = 5391
β = 2.6 (wt%)

(Fire resistance evaluation result of Example 1)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

(Example 2)
In Example 2, the fireproof performance evaluation of the outer heat insulating fireproof outer wall structure 1 composed of the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 490 (kg / m ³ )
t = 50 (mm)
α = 8.1 (wt%)
d × t ³ × α ÷ 100,000 = 4961
β = 2.8 (wt%)

(Fire resistance evaluation result of Example 2)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

(Example 3)
In Example 3, fire resistance performance evaluation of the outer heat insulating fireproof outer wall structure 1 constituted by the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 510 (kg / m ³ )
t = 50 (mm)
α = 11.8 (wt%)
d × t ³ × α ÷ 100,000 = 7526
β = 2.9 (wt%)

(Fire resistance evaluation result of Example 3)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

Example 4
In Example 4, the fireproof performance evaluation of the outer heat insulating fireproof outer wall structure 1 composed of the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 275 (kg / m ³ )
t = 75 (mm)
α = 11.4 (wt%)
d × t ³ × α ÷ 100,000 = 13226
β = 2.9 (wt%)

(Fire resistance evaluation result of Example 4)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

(Example 5)
In Example 5, the fireproof performance evaluation of the outer heat insulating fireproof outer wall structure 1 composed of the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 350 (kg / m ³ )
t = 50 (mm)
α = 7.9 (wt%)
d × t ³ × α ÷ 100000 = 3456
β = 2.9 (wt%)

(Fire resistance evaluation result of Example 5)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

(Example 6)
In Example 6, the fireproof performance evaluation of the outer heat insulating fireproof outer wall structure 1 constituted by the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. In addition, glass wool having a density of 24 kg / m ³ was filled between the vertical frame material 21 and the vertical frame material 21 constituting the structural member 2 as the filled heat insulating material 25. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 375 (kg / m ³ )
t = 50 (mm)
α = 11.5 (wt%)
d × t ³ × α ÷ 100000 = 5391
β = 2.6 (wt%)

(Fire resistance evaluation result of Example 6)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from the outside: The structural member 2 was not carbonized or ignited.

(Comparative Example 1)
In Comparative Example 1, fire resistance performance evaluation of the outer wall structure 1 composed of the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 375 (kg / m ³ )
t = 37 (mm)
α = 11.8 (wt%)
d × t ³ × α ÷ 100000 = 2184
β = 2.6 (wt%)

(Results of fire resistance evaluation of Comparative Example 1)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from outside: Carbonization was observed in the structural member 2.

(Comparative Example 2)
In Comparative Example 2, the fire performance evaluation of the outer wall structure 1 composed of the structural member 2, the interior member 3, the heat insulating plate material 4 and the exterior member 5 was performed. The following materials were used for the lightweight cellular concrete panel 55 constituting the lightweight cellular concrete panel layer 54.
d = 500 (kg / m ³ )
t = 37 (mm)
α = 8.1 (wt%)
d × t ³ × α ÷ 100,000 = 2051
β = 2.6 (wt%)

(Fire resistance evaluation result of Comparative Example 2)
Indoor heating: No carbonization or ignition was observed in the structural member 2.
Heating from outside: Carbonization was observed in the structural member 2.

  As shown in Examples 1 to 6, as a result of heating from the indoor side and the outdoor side, carbonization and ignition were not seen in the structural member 2, so the outer heat insulating fireproof outer wall structure 1 is “fireproof structure”. I found out that

  As a result of earnest examination, to achieve the fireproof outer wall structure of the wooden building's outer heat insulation, the construction is simple, low cost, only one kind of exterior member and only one layer of exterior member is achieved. The conclusion was that the exterior member was a lightweight cellular concrete panel 55. The outer heat insulating fireproof outer wall structure 1 of the present embodiment has a structural face member 24 attached to the outdoor side of the structural member 2 made of wood, and a thickness attached to the outdoor side face of the structural face member 24. Phenol foam heat insulating plate 41 having a length of 12 mm or more and 80 mm or less, an aluminum foil layer 51 located on the outdoor side surface of the phenol foam heat insulating plate 41, and a non-combustible attached to the outdoor side surface of the aluminum foil layer 51 And a lightweight cellular concrete panel 55 attached as an exterior member to a surface on the outdoor side of the trunk edge material 53a.

The density of the lightweight cellular concrete panel 55 is d (kg / m ³ ), the thickness of the lightweight cellular concrete panel 55 is t (mm), and the ignition loss value of the lightweight cellular concrete panel 55 is α (wt%). Then, 200 ≦ d ≦ 550, 45 ≦ t ≦ 100, 5 ≦ α ≦ 15, and 3000 ≦ d × t ³ × α ÷ 100000 ≦ 30000 are satisfied.

  In addition, in order to provide the heat insulation outer wall structure of the wooden building of the present invention with better heat insulation performance, when the architectural style is a wooden framed wall construction method, between the columns and the studs and between the columns and the studs You may be made to fill the filling heat insulating material 25 between. Here, the said pillar and the interposition pillar comprise the structural member in a wooden frame wall construction method. Further, in the case of the wooden frame wall construction method, the filling heat insulating material 25 may be filled between the vertical frame material 21 and the vertical frame material 21 as described above.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. In this embodiment, although the case where this invention was applied to the wall body used for a wooden frame wall construction method was demonstrated as an example, you may apply to other wall bodies, such as a wooden frame construction method.

  According to the present invention, the exterior member can be composed of only one type of material and a single exterior member, that is, the lightweight cellular concrete panel 55, has excellent fire resistance performance and heat insulation performance, and is easy to construct. It is possible to provide an external heat-insulating fire-resistant outer wall structure for a wooden building which is low in cost. Therefore, it becomes possible to easily construct a wooden fire-resistant building having excellent heat insulation performance, and the wooden construction can be more widely spread.

DESCRIPTION OF SYMBOLS 1 ... Outer wall structure, 2 ... Structural member, 3 ... Interior member, 4 ... Thermal insulation board material, 5 ... Exterior member, 21 ... Vertical frame material, 22 ... Upper frame material, 23 ... Lower frame material, 24 ... Structural surface material 25 ... Filling heat insulating material, 31 ... Interior undercoat layer, 32 ... Interior overcoat layer, 41 ... Phenol foam heat insulating plate, 51 ... Aluminum foil layer, 52 ... Waterproof layer, 53 ... Breathable layer, 53a ... Body edge material, 54: Lightweight cellular concrete panel layer, 55: Lightweight cellular concrete panel.

Claims (3)

A structural face material attached to the outdoor side of a structural member made of wood;
A phenol foam heat insulating plate having a thickness of 12 mm or more and 80 mm or less attached to the surface on the outdoor side of the structural face material;
An aluminum foil layer located on the outdoor side surface of the phenol foam heat insulating plate;
A non-combustible trunk material attached to the outdoor side surface of the aluminum foil layer;
A lightweight cellular concrete panel attached to the outdoor side surface of the waistband,
When the density of the lightweight cellular concrete panel is d (kg / m ³ ), the thickness of the lightweight cellular concrete panel is t (mm), and the ignition loss value of the lightweight cellular concrete panel is α (wt%). In addition,
250 ≦ d ≦ 400 ,
45 ≦ t ≦ 75 ,
8 ≦ α ≦ 13 , and
3000 ≦ d × t ³ × α ÷ 100,000 ≦ 15000
We meet the,
The ignition loss value α is calculated by α (wt%) = (weight A−weight B) × 100 / weight B, and the weight A is the weight of the lightweight cellular concrete panel powder dried to a constant weight. The weight B is a weight of the powder after heating the powder of the weight A at 1000 ° C. for 1 hour, and is an outer heat insulating fireproof outer wall structure of a wooden building. The outer heat insulating fireproof outer wall structure of a wooden building according to claim 1, wherein d, t, and α satisfy 5000 ≦ d × t ³ × α ÷ 100000 ≦ 15000. Between the vertical frame and the vertical frame constituting the structural member, or between the pillars and studs, and studs and studs constituting the structural member, the heat insulating material is filled, according to claim 1 or 2 Outer heat-insulated fire-resistant outer wall structure of wooden buildings.

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