JP6684848B2 - Wood structural member - Google Patents

Description

  The present invention relates to a wooden structural member.

  Patent Document 1 discloses a load supporting layer that constitutes a core portion that supports a long-term load, a non-burning layer that is disposed on the outer periphery of the load supporting layer, and a burn-up layer that is disposed on the outer periphery of the non-burning layer. A wooden laminated pillar composed of layers is disclosed. In this prior art, the flame-retardant layer is obtained by alternately arranging a single wood material and a high heat capacity material made of a non-combustible material such as mortar having a heat capacity (heat absorption amount) larger than that of wood and adhesively joining them together. It is said that.

  Patent Document 2 discloses a wooden structural member in which an outer layer portion in which a fuel stop layer and a burn-up layer are integrated is fastened to a core member with screws. In this prior art, the fuel stop layer has a wood part and a mortar plate arranged along the outer peripheral surface of the core part. Further, the mortar board is formed in a plate shape having a substantially rectangular cross section, and is arranged with the longitudinal direction as the axial direction of the wooden structural member.

  Here, the manufacturing method of producing the mortar bar (high heat capacity material, mortar plate) that constitutes the fire stop layer and joining it to the wood has a limit in producing the mortar bar with high accuracy, and therefore the mortar bar is burned. It is difficult to make a close contact with the substratum without a gap. Therefore, there is a limit to the absorption of the combustion heat of the burn-up layer in the mortar bar (fuel stop layer).

JP, 2005-36456, A JP, 2015-25245, A

  An object of the present invention is to provide a wood structural member having improved heat absorption performance that allows the combustion stop layer to absorb the combustion heat of the burn-up layer.

A first aspect includes a cylindrical wooden load support portion, and a fuel stop layer provided outside the load support portion and made of a non-combustible material or a material having an ignition temperature higher than that of the load support portion. It is a wooden structural member.

The second aspect is a load supporting part made of wood and having a substantially square columnar shape with arc-shaped corners, and is provided outside the load supporting part and is made of a non-combustible material or a material having a higher ignition temperature than the load supporting part. And a fire-retardant layer.

A third aspect is the wood structural member according to the first aspect or the second aspect , in which the fire stop layer is made of gypsum.

A fourth aspect is the wood structural member according to the first aspect or the second aspect , wherein the fuel stop layer is made of a grout material.

  ADVANTAGE OF THE INVENTION According to this invention, the heat absorption performance which makes the combustion stop layer absorb the combustion heat of the combustion generation layer of a wooden structure member can be improved.

It is a perspective view of the building of the flat slab structure using the wooden pillar. It is sectional drawing of the cross section orthogonal to the axial direction of a wooden pillar. It is a longitudinal cross-sectional view along the X direction of the joint portion between the wooden pillar and the slab. FIG. 6 is a vertical cross-sectional view taken along the X direction in a state where gypsum is filled between the load supporting portion of the wooden pillar and the burn-up layer. It is a perspective view of the state where the plaster is poured between the load supporting portion and the burn-up layer of the wooden pillar. It is the front view which looked at the wooden pillar after a fireproof test from the direction of an axis. It is sectional drawing of the cross section orthogonal to the axial direction of the wooden pillar of a 1st modification. It is sectional drawing of the cross section orthogonal to the axial direction of the wood pillar of a 2nd modification. It is a perspective view of a wooden beam.

<First embodiment>
A wooden pillar and a building using the wooden pillar will be described as an example of the wooden structural member of the present invention. Note that the vertical direction is the Z direction, and two mutually orthogonal horizontal directions orthogonal to the vertical direction are the X direction and the Y direction. Further, the axial direction of the wooden pillar 100 described later is the vertical direction (Z direction).

(Structure of wooden columns and buildings)
As shown in FIG. 1, the building 10 has a flat slab structure, and the slab 12 in which a beam does not project from the lower surface 12L is supported by a plurality of columnar wooden pillars 100. Further, the slab 12 of this embodiment is made of reinforced concrete. A concrete capital for receiving the slab 12 may be provided on the pillar head of the wooden pillar 100.

  As shown in FIGS. 2 and 3, the wooden pillar 100 includes a cylindrical wooden load support portion 110 (see also FIG. 5) and a cylindrical wooden material arranged outside the load support portion 110 with a space therebetween. No. 3 of the burn-up layer 130 (see also FIG. 5), and the cylindrical fuel-stop layer 120 formed by filling and hardening the plaster S between the load support portion 110 and the burn-in layer 130. It has a layered structure.

  The cylindrical wooden load supporting portion 110 has rigidity and strength capable of supporting the load of the slab 12 that the wooden pillar 100 bears. In addition, the load supporting unit 110 of the present embodiment is configured by a laminated material in which a plurality of plate-shaped single wooden materials 112 (see FIG. 6) are laminated and pressed to be integrated.

  The cylindrical burn-up layer 130 of the present embodiment is a cylindrical LVL (Laminated Veneer Lumber). The burn-up layer 130 may be, for example, a single-layer laminated material (LVL) or a rectangular laminated plate (CLT (Cross Laminated Timber)) processed into a cylindrical shape instead of the cylindrical LVL.

  The fuel stop layer 120 is made of gypsum S which is an incombustible material, and thus is incombustible, and has a larger heat capacity than the load support portion 110 and the burn-up layer 130 made of wood. A cylindrical wire net may be embedded in the fuel stop layer 120.

  The upper surface 120U of the fuel stop layer 120 of the wooden pillar 100 is located slightly below the upper end surface 130U of the burnout layer 130 and the upper end surface 110U of the load support portion 110. Therefore, in the upper end 100U of the wooden pillar 100, the recess 102 is formed in a portion corresponding to the fuel stop layer 120.

  Then, the concave portion 102 of the upper end portion 100U of the wooden pillar 100 is filled with concrete when the slab 12 is cast. From another viewpoint, the convex portion 14 protruding from the lower surface 12L of the slab 12 is engaged with the concave portion 102 of the upper end portion 100U of the wooden pillar 100.

(Wood column manufacturing (construction) method)
Next, an example of a method of manufacturing (constructing) the wooden pillar 100 will be described.

  First, a plurality of plate-shaped wooden single materials 112 (see FIG. 6) are laminated and pressed, that is, pressure is applied to the wooden single material 112 coated with the adhesive so that the adhesive is sufficiently cured, and the adhesive is sufficiently cured. A quadrangular prismatic laminated material is produced by completing the bonding by using the above method. Next, the load supporting portion 110 of the wooden pillar 100 shown in FIGS. 2 and 3 is manufactured by cutting the laminated material of the square pillar into a cylindrical shape.

  The burn-up layer 130 is formed by winding a plate-shaped orthogonal laminated plate around a rod-shaped jig to form a cylindrical shape. When the plate-shaped orthogonal laminated plates are wound, the fiber directions of the layers are inclined in the left-right direction with respect to the axial direction of the cylinder, and are wound in the reverse direction.

  As shown in FIG. 4 and FIG. 5, the column-shaped load supporting portion 110 is arranged and fixed in the cylindrical combustion-assisting layer 130 with a gap T therebetween. Note that any method may be used to fix the load supporting portion 110 and the burn-up layer 130 with a gap T therebetween.

  As an example, the load supporting part 110 and the burn-up layer 130 are fixed with a gap T using the fixing jig 50 shown in FIG. The fixing jig 50 includes a tubular ring portion 52 and a wedge-shaped spacer 54. A plurality of spacers 54 are arranged at intervals in the circumferential direction. A cylindrical combustion margin layer 130 is arranged and fixed inside the ring portion 52, and the gap T between the load support portion 110 and the combustion margin layer 130 is made constant by the spacer 54.

  Then, as shown in FIG. 5, the fluid-filled gypsum S is poured from above into the gap T between the load support portion 110 and the burn-up layer 130, and the plaster S is cured after the filling, whereby the fuel-stop layer 120 is formed. It is formed. Note that FIG. 4 is a diagram of a state in which the fluid gypsum S is being poured into and filled in the gap T between the load supporting portion 110 and the combustion substratum 130.

  When the wire mesh is embedded in the fuel stop layer 120, a wire mesh processed into a cylindrical shape is provided in the gap T between the load support portion 110 and the combustion stock layer 130, and then the plaster S is poured from above and filled.

(Action and effect)
Next, the operation and effect of this embodiment will be described.

  As shown in FIGS. 4 and 5, since the plaster S is poured from above into the gap T between the burn-up layer 130 and the load support portion 110 and the plaster S is cured, the fuel stop layer 120 can be formed. For example, the workability is improved as compared with a method of joining a mortar bar to produce a flame-retardant layer.

  Further, for example, as compared with the method of joining the mortar bars to form the fuel stop layer, the outer shape of the cross section orthogonal to the axial direction can be easily formed into a circle, a curved surface, or a complicated shape. it can. That is, it is possible to easily manufacture the wooden pillar 100 having a circular outer shape, a curved surface, or a complicated shape.

  In addition, as shown in FIGS. 2, 3 and 6, in the wooden pillar 100, the load support portion 110 that supports the load is covered with the fuel stop layer 120 and the burnout layer 130.

  Therefore, in the event of a fire, first, the outermost combustion margin layer 130 gradually burns to form a carbonized layer (heat insulating layer) 132 (see FIG. 6) around the fuel stop layer 120. As a result, the heat of fire that enters the fuel stop layer 120 and the load support portion 110 is reduced. Further, at this time, the heat of fire is absorbed (absorbed) by the fuel stop layer 120 having a larger heat capacity than that of the load support portion 110 and the burn-up layer 130, and the heat of fire entering the load support portion 110 is further reduced. Therefore, since the combustion of the load supporting portion 110 is suppressed, the fire resistance performance of the wooden pillar 100 is improved.

  Furthermore, the combustion stop layer 120 made of gypsum S, which is a non-combustible material, can stop the combustion of the combustion substratum layer 130 (natural extinction). Therefore, the load can be supported by the load supporting unit 110 even after the fire ends (after the fire is extinguished).

  Further, since the gypsum S is in a fluid state before being hardened, it is in close contact with the combustion stock layer 130 and the load supporting portion 110. Further, the plaster S enters the wood grain (concavo-convex) of the surfaces of the load supporting portion 110 and the combustion layer 130. Therefore, since the adhesion between the burn-up layer 130 and the burn-stop layer 120 after curing is good, the combustion heat of the burn-up layer 130 is effectively absorbed by the burn-stop layer 120. That is, as compared with the case where the combustion margin layer 130 and the fuel stop layer 120 are not in close contact with each other and a minute gap is formed, the heat absorption performance for absorbing the combustion heat of the combustion margin layer 130 into the fuel stop layer 120 is improved. improves.

  Further, the gypsum S that constitutes the fuel stop layer 120 contains a large amount of crystal water, and when exposed to a flame or heat, the water absorbs heat as it is released into the air as steam. Therefore, the heat absorption performance of allowing the combustion stop layer 120 to absorb the combustion heat of the combustion margin layer 130 is further improved.

  The burn-up layer 130 has a tubular shape, and the cross section orthogonal to the axial direction has a circular outer shape (the cross section orthogonal to the axial direction of the wood pillar 100 has a circular outer shape). Therefore, the fire resistance performance is improved as compared with a wood column (square column) having an outer shape with a corner that is heated in two directions.

  In addition, when the wire mesh is embedded in the fuel stop layer 120, the fuel stop layer 120 is prevented from falling off during combustion, so that the fire resistance is further improved.

  Further, as shown in FIG. 3, the lower surface 12L of the slab 12 is in close contact with the fuel stop layer 120 made of gypsum S in the wooden pillar 100 when pouring concrete, and is integrated with the fuel stop layer 120. Further, the upper surface 12U of the slab 12 is in close contact with the fuel stop layer 120 when the plaster S is poured to form the fuel stop layer 120, and is integrated with the fuel stop layer 120. As described above, since the fuel stop layer 120 of the wooden pillar 100 and the slab 12 are in close contact with each other and are continuous, the fire resistance performance is improved as compared with the structure in which the fuel stop layer 120 is discontinuous with the slab 12.

  Further, as described above, the wooden pillar 100 has good adhesion between the fuel stop layer 120 and the burn-up layer 130 and the load support portion 110, so that the wooden pillar 100 is orthogonal to the compression force in the direction orthogonal to the axial direction and the axial direction. The stress transfer performance such as directional shear force is improved.

(Fire resistance test)
Next, the result of the fire resistance test of the wooden pillar 100 of this embodiment will be described. In addition, the fire resistance test was performed according to the fire prevention performance test / evaluation work method manual of a designated performance evaluation institution (for example, Building Material Testing Center).

  FIG. 6 schematically shows the wooden pillar 100 after the fire resistance test. As shown in FIG. 6, the combustion stock layer 130 of the wooden pillar 100 burns to form a carbonized layer (heat insulating layer) 132. However, the inner peripheral portion 134 of the combustion margin layer 130, which is in close contact with the fuel stop layer 120, remains unburned. Therefore, it can be seen that the combustion heat is effectively absorbed in the combustion stop layer 120 because the combustion margin layer 130 is in close contact with the combustion stop layer 120.

  Further, since the fuel stop layer 120 is in close contact with the load support portion 110 without dropping off after the combustion, it is understood that the load can be supported together with the load support portion 110 even after the combustion.

[Modified example of wooden pillar]
Next, a modified example of the wooden pillar will be described.

(First modification)
The fuel stop layer 121 of the wooden pillar 101 of the first modified example shown in FIG. 7 is composed of a fuel stop portion 123 formed by filling and hardening gypsum S and a wooden connecting member 125.

  Further, in a state in which the connecting member 125 is arranged and joined in the gap T between the load supporting portion 110 and the combustion margin layer 130, the plaster S is poured and filled, and then hardened to form the fuel stop portion 123.

(Second modified example)
A wood pillar 200 of a second modified example shown in FIG. 8 is a substantially square pillar-shaped wood load supporting portion 210, and a rectangular tubular wood-like burn-up layer 230 arranged outside the load supporting portion 210 with a space. And a substantially square tubular fuel stop layer 220 formed by filling and hardening the gypsum S between the load supporting portion 210 and the burn-up layer 230, and has a three-layer structure.

  The corners 212 of the load supporting portion 210 are arcuate. That is, a so-called corner R is formed at the corner portion 212 of the load support portion 210.

  Further, the burn-up layer 230 is formed in a rectangular tube shape by joining four plate members (orthogonal laminated plates) 232.

  In this way, the outer shape of the cross section orthogonal to the axial direction of the burn-up layer 230 of the wood pillar 200 of the second modified example is quadrangular (the outer shape of the cross section perpendicular to the axial direction of the wood pillar 200 is quadrangular. Exist). Therefore, the corner portion 202 of the wooden pillar 200 is heated in two directions.

  However, since the corner R of the load supporting portion 210 is formed with the corner R, the thickness of the corner 222 of the fuel stop layer 220 increases accordingly. That is, the thickness L1 when the corner R is formed is thicker than the thickness L2 when the corner R is not formed. Therefore, the fire resistance performance of the corner portion 202 of the wooden pillar 200 that is heated in two directions is improved.

  In the second modified example of the wooden pillar 200 as well, like the first modified example of the wooden pillar 101, a wood connecting member 125 (see FIG. 7) may be provided in the fuel stop layer 220.

<Second embodiment>
A wood beam will be described as an example of the wood structural member of the present invention. The same members as those in the first embodiment are designated by the same reference numerals, and overlapping contents are simplified or omitted. The axial direction of the wooden beam 300 is the Y direction.

(Wood beam structure)
As shown in FIG. 9, the wooden beam 300 includes a load supporting portion 310 made of a quadrangular prismatic wooden material, a substantially U-shaped wood-based combustion margin layer 330 arranged outside the load supporting portion 310 with a space, It has a three-layer structure of a substantially U-shaped fuel stop layer 320 formed by filling and hardening the gypsum S between the load support portion 310 and the burn-up layer 330. In addition, a substantially U-shaped wire net may be embedded in the fuel stop layer 320.

  The wooden beam 300 supports a concrete slab (not shown), and the upper surface 300U of the wooden beam 300 is covered with the slab. Therefore, since the fire resistance of the upper surface 300U of the wooden beam 300 is ensured by the slab, the upper surface 310U of the load support portion 310 is not covered by the fuel stop layer 320.

(Wood beam manufacturing (construction) method)
Next, an example of a method of manufacturing (constructing) the wooden beam 300 will be described.

  Laminating a plurality of plate-like wooden single materials 112 (see FIG. 6) and pressing, that is, applying pressure to the adhesive-applied wooden single materials 112 to bring them into close contact, and to make sure that the adhesive is sufficiently cured By completing the above, the load supporting portion 310 of the wooden beam 300 is manufactured.

  Further, the three plate members (orthogonal laminated plates) 332 are joined in a substantially U-shape to form the combustion margin layer 330.

  Then, the quadrangular prism load supporting portion 310 is arranged and fixed in the U-shaped combustion margin layer 330 with a gap T therebetween. Any method may be used to fix the load supporting portion 310 and the burn-up layer 330 with a gap T therebetween.

  As an example, as shown in FIG. 9, the end face is fixed by a plate-like fixing member 350 made of wood or steel and the upper surface is fixed by a plate-like fixing member 352 made of wood or steel, and a wedge-shaped spacer 354 is formed. By driving into the gap T, the load supporting portion 310 and the burn-up layer 330 are fixed with the gap T.

  Then, the fluid gypsum S is poured from above into the gap T between the load supporting portion 310 and the burn-up layer 330, and the plaster S is cured after filling, whereby the fuel stop layer 320 is produced.

  When the metal mesh is embedded in the fuel stop layer 320, the metal mesh is provided in the gap T between the load support portion 310 and the combustion stock layer 330, and then the plaster S is poured from above to be filled.

(Action and effect)
Next, the operation and effect of this embodiment will be described.

  Since the plaster S is poured from above to fill the gap T between the burn-up layer 330 and the load supporting portion 310 and the plaster S is hardened to form the flame-retardant layer 320, for example, a mortar bar is joined to the flame-retardant layer. The workability is improved as compared with the method of manufacturing.

  In the wooden beam 300, a load supporting portion 310 that supports a load is covered with a combustion stop layer 320 and a combustion margin layer 330, and the combustion margin layer 330 burns to form a carbonized layer (heat insulating layer) around the combustion prevention layer 320. By forming 132 (see FIG. 6), the heat of fire that penetrates into the flame stop layer 320 and the load support portion 310 is reduced. Further, the heat of the fire is absorbed (absorbed) by the fuel stop layer 120. Therefore, since the combustion of the load support portion 310 is suppressed, the fire resistance performance of the wooden beam 300 is improved.

  Further, since the combustion stop layer 320 made of the non-combustible material gypsum S can stop the combustion of the combustion subsidence layer 330 (natural extinction), the load supporting portion 310 is loaded even after the fire ends (after the extinction). Can be supported.

  Moreover, since the adhesion between the burn-up layer 330 and the cured burn-stop layer 320 is good, the combustion heat of the burn-up layer 330 is effectively absorbed by the burn-stop layer 320.

  Further, the gypsum S that constitutes the fuel stop layer 320 contains a large amount of crystal water, and when exposed to a flame or heat, the water absorbs heat as it is released into the air as steam. Therefore, the heat absorption performance of allowing the combustion stop layer 320 to absorb the combustion heat of the combustion margin layer 330 is further improved.

  With such a structure, the fire resistance of the wooden beam 300 is improved. As described above, the fire resistance of the upper surface 300U of the wooden beam 300 is ensured by the slab (not shown).

  In addition, like the wooden pillar 101 (see FIG. 7) of the first modified example of the first embodiment, a wood coupling member 125 (see FIG. 7) may be provided in the fuel stop layer 320. Further, as in the wooden pillar 200 (see FIG. 8) of the second modified example of the first embodiment, the corner R may be formed at the lower corner of the load support portion 310.

<Other>
The present invention is not limited to the above embodiment.

  In the above embodiment, the filling material filled between the load supporting portions 110, 210, 310 and the burn-up layers 130, 230, 330 and hardened was the gypsum S, but the filling material is not limited to this. For example, it may be grout, concrete, mortar and fiber reinforced concrete.

  In addition, since the grout material has excellent fluidity, the filling efficiency between the load supporting portion and the burn-up layer is improved. Further, since the grout material has a small shrinkage due to hardening and has good adhesion between the burn-in layer and the burn-stop layer of the wooden structural member, the combustion heat of the burn-in layer is effectively absorbed by the burn-stop layer.

  Alternatively, it may be a filler that is not incombustible but has a higher ignition temperature than the load supporting portions 110, 210, 310, for example, a caulking material made of resin. What is essential is that the filler is made of a non-combustible material or a material having an ignition temperature higher than that of the load supporting portion.

  Further, the load supporting portion made of wood and the combustion stock layer made of wood may be made of wood. For example, wood used for general wooden construction such as Yonematsu, Karamatsu, cypress, cedar and Asunaro can be used.

  Further, it goes without saying that the present invention can be implemented in various modes without departing from the scope of the present invention.

110 load supporting part 100 wooden pillar (an example of a wooden structural member)
101 Wooden pillar (an example of wooden structural member)
120 Fuel stop layer 123 Fuel stop part (fuel stop layer)
130 Combustion layer 200 Wooden pillar (an example of a wooden structural member)
210 Load-bearing part 220 Fire stop layer 230 Combustion layer 300 Wood beam (an example of wood structural member)
310 Load-bearing part 320 Fire-stop layer 330 Combustion layer
S Gypsum (an example of filler)

Claims (4)

Cylindrical wood load support,
Provided in close contact with the entire circumferential surface of the load supporting portion, a fire stop layer made of a material having a higher ignition temperature than the load supporting portion or the load supporting portion,
A wire mesh embedded in the fire-stop layer,
A wooden structural member including. A load supporting portion made of wood and having a substantially rectangular column shape whose corners are arc-shaped,
Provided in close contact with the entire circumferential surface of the load supporting portion, a fire stop layer made of a material having a higher ignition temperature than the non-combustible material or the load supporting portion,
A wire mesh embedded in the fire-stop layer,
A wooden structural member including. The flame-retardant layer is made of gypsum,
The wooden structural member according to claim 1 or 2. The fuel stop layer is made of grout material,
The wooden structural member according to claim 1 or 2.