Beam construction

Abstract

This provides a beam structure that offers high workability for applying fire-resistant coatings to penetrations in wooden beams. [Solution] The beam structure 10 has a wooden beam 11 and a through-hole 12 that penetrates the wooden beam 11. The through-hole 12 is a rectangular opening provided eccentrically above the wooden beam 11 in the beam-length direction. The wooden beam 11 has an upper reinforcing member 15 that covers the upper surface of the through-hole 12 and reinforces the wooden beam 11. The corners of the through-hole 12 of the wooden beam 11 are reinforced with reinforcing tape 17.

Description

Technical Field

[0001] The present disclosure relates to a beam structure having a wooden beam.

Background Art

[0002] For example, as in Patent Document 1, in a wooden beam, a circular through-hole (so-called sleeve) penetrating the wooden beam in the beam width direction may be provided. Such through-holes are used as equipment spaces such as piping passages, and are provided at the center in the beam forming direction with a diameter of about 1 / 4 to 1 / 3 of the beam forming.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the above beam structure, if the through-hole is provided eccentrically below the beam in the beam-length direction of the wooden beam, it may have an upper beam-side reinforcing member that reinforces the beam side above the through-hole. With this configuration, the rigidity of the wooden beam can be increased in the portion where the through-hole is formed.

[0008] In the above beam structure, if the through-hole is provided eccentrically below the wooden beam in the beam-length direction, it is preferable that a ceiling material is provided below the wooden beam, spaced a predetermined distance from the lower end of the wooden beam, and that the space above the ceiling material and the through-hole communicating with the ceiling material be used as equipment space. With this configuration, the space above the ceiling material and the space formed by the through-hole can be used as equipment space.

[0009] In the beam structure described above, it is preferable that the corners of the through-holes are reinforced with reinforcing tape. This configuration makes it less likely for cracks to occur in the corners. [Brief explanation of the drawing]

[0010] [Figure 1] In the first embodiment, Figure 1 is a perspective view showing the schematic configuration of the beam structure. [Figure 2] In the first embodiment, Figure 2 schematically shows the stress generated in a wooden beam when a downward distributed load is applied. [Figure 3] In the first embodiment, Figure 3 is an exploded perspective view of the beam structure. [Figure 4] In the first embodiment, Figure 4 is a cross-sectional view showing a schematic configuration of a modified beam structure. [Figure 5] In the second embodiment, Figure 5 is a perspective view showing the schematic configuration of the beam structure. [Figure 6] In the second embodiment, Figure 6 is a perspective view showing an upper beam side reinforcing member that reinforces the through-hole forming portion of the wooden beam from both sides in the beam width direction. [Figure 7] In the second embodiment, Figure 7 schematically shows the stress generated in a wooden beam when a downward distributed load is applied. [Figure 8] In the second embodiment, Figure 8 is an exploded perspective view of the beam structure. [Figure 9] In the second embodiment, Figure 9 is a schematic diagram showing an example of the application of a beam structure. [Modes for carrying out the invention]

[0011] (First Embodiment) A first embodiment of the beam structure will be described with reference to Figures 1 to 4. As shown in Figure 1, the beam structure 10 comprises a wooden beam 11 and a through-hole 12. The wooden beam 11 is formed, for example, from laminated timber. The through-hole 12 penetrates the wooden beam 11 in the beam width direction. The through-hole 12 is eccentrically positioned on the upper side in the beam depth direction. "Eccentric" means that the center of gravity of the outer shape of the through-hole 12 in a side view is located on the upper side in the beam depth direction. The lower surface 12b of the through-hole 12 is located at a position approximately half the beam depth D of the wooden beam 11 from the upper surface 11a of the wooden beam 11. In a side view of the wooden beam 11, the through-hole 12 has a square shape, more specifically a rectangular shape. In the wooden beam 11, the part where the beam depth dimension is reduced due to the formation of the through-hole 12 is the through-hole forming part 11A.

[0012] The beam structure 10 includes an upper reinforcing member 15 that reinforces the through-hole forming portion 11A of the wooden beam 11. In the wooden beam 11, the beam structure 10 is formed in a plate shape. The upper reinforcing member 15 is provided so as to cover the upper open surface 12c of the through-hole 12. The upper reinforcing member 15 is disposed in a reinforcing member fitting portion 13 provided on the wooden beam 11. In a side view of the beam structure 10, the reinforcing member fitting portion 13 is formed to be wider than the through-hole 12 in the beam axis direction. The upper reinforcing member 15 is fixed to the wooden beam 11 by, for example, an adhesive or screw (not shown). The upper reinforcing member 15 is made of a material having higher strength (allowable stress value) than the wooden beam 11, such as steel.

[0013] As shown in Figure 2, when a downward distributed load w acts on the wooden beam 11, compressive stress σ3 is generated in the upper part of the wooden beam 11, while tensile stress σ1 is generated in the lower part of the wooden beam 11. Therefore, cracks are likely to form near the corner 14 of the penetration opening 12.

[0014] As shown in Figure 1, the beam structure 10 is equipped with a reinforcing tape 17 in relation to the occurrence of cracks near the corner portion 14. The reinforcing tape 17 is applied so as to straddle the corner portion 14. More specifically, the reinforcing tape 17 is applied so as to pass through the corner portion 14 of the through-hole 12 and straddle one side of the wooden beam 11, the bottom surface 11b of the wooden beam 11, and the other side of the wooden beam 11. The reinforcing tape 17 is made of, for example, carbon fiber.

[0015] The reinforcing tape 17 only needs to be provided so as to straddle the corner portion 14. For example, the reinforcing tape 17 may be attached across one side of the wooden beam 11, the top reinforcing material 15, and the other side of the wooden beam 11. Alternatively, for example, the reinforcing tape 17 may be provided only near the corner portion 14. In this case, the reinforcing tape 17 may be provided along the beam depth direction in a side view, or along a direction intersecting the beam depth direction.

[0016] As shown in FIG. 3, after manufacturing a wooden beam 11 having a through-hole 12 and a reinforcing member fitting portion 13, an upper surface reinforcing member 15 is disposed in the reinforcing member fitting portion 13. Then, the beam structure 10 is completed by fixing the upper surface reinforcing member 15 to the wooden beam 11.

[0017] The operation and effects of the first embodiment will be described. (1-1) The beam structure 10 has a wooden beam 11 and a through-hole 12 penetrating the wooden beam 11. The through-hole 12 is provided at a position eccentric upward in the beam forming direction of the wooden beam 11. The through-hole 12 is a rectangular opening in a side view of the beam structure 10.

[0018] When applying a fire-resistant coating to the wooden beam 11 using a fire-resistant plate material in the beam structure 10, it is only necessary to cut the fire-resistant plate material to fit the inner surface shape of the through-hole 12. As a result, a special manufacturing method or processing method is not required for manufacturing the fire-resistant coating material. As a result, the workability of applying the fire-resistant coating to the through-hole 12 can be improved.

[0019] Here, when a through-hole is formed at the center in the beam forming direction, the through-hole forming portion is formed on the upper side and the lower side of the through-hole. In this regard, in the beam structure 10, since the through-hole 12 is provided eccentrically on one side in the beam forming direction, the through-hole forming portion 11A is formed only on the lower side of the through-hole 12. As a result, by increasing the dimensional value of the through-hole forming portion 11A in the beam forming direction, the stress concentration of the through-hole forming portion 11A can be alleviated and the rigidity can be increased. As a result, the deflection of the wooden beam 11 in the vicinity of the through-hole 12 can be suppressed.

[0020] (1-2) The through-hole 12 is provided eccentrically upward in the beam forming direction of the wooden beam 11. The beam structure 10 has an upper surface reinforcing member 15 provided so as to cover the upper open surface 12c of the through-hole 12 and reinforce the wooden beam 11. Since the upper surface of the through-hole 12 is reinforced by the upper surface reinforcing member 15, the rigidity of the beam structure 10 around the through-hole 12 can be increased.

[0021] (1-3) In the beam structure 10, the corner portion 14 of the through-hole 12 is reinforced with reinforcing tape 17. This effectively increases the rigidity of the corner portion 14, which is prone to cracking.

[0022] The first embodiment can be implemented with the following modifications. The first embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically. The beam structure 10 does not necessarily need to be equipped with reinforcing tape 17.

[0023] The beam structure 10 does not necessarily have an upper reinforcing member 15. In this case, the wooden beam 11 does not require a reinforcing member fitting portion 13, and an open through-hole 12 is formed at the top. As shown in Figure 4, the beam structure 10 may also have a floor 18 as an upper reinforcing material, which is installed on the upper surface 11a of the wooden beam 11 and connected to the wooden beam 11 via, for example, studs. In this configuration, the wooden beam 11 does not require a reinforcing material fitting part 13, and the floor 18 is, for example, a CLT floor or a concrete floor.

[0024] The side view shape of the through-hole 12 can be rectangular or, for example, trapezoidal. In this case, the through-hole 12 is formed so that a pair of parallel sides face each other in the vertical direction. Furthermore, by having the lower side of the pair of sides be the shorter side, the occurrence of cracks at the corner portion 14 can be effectively suppressed.

[0025] (Second Embodiment) A second embodiment of the beam structure will be described with reference to Figures 5 to 8. The beam structure of the second embodiment has the same main configuration as the beam structure of the first embodiment, although it differs from the beam structure of the first embodiment in terms of the position of the penetration openings. Therefore, in the second embodiment, the parts that differ from the first embodiment will be described in detail, and the same parts as in the first embodiment will be denoted by the same reference numerals, and their detailed description will be omitted.

[0026] As shown in Figure 5, the beam structure 20 comprises a wooden beam 21 and a through-hole 22. The through-hole 22 penetrates the wooden beam 21 in the beam width direction. The through-hole 22 is eccentrically positioned on the lower side in the beam depth direction. The upper surface 22a of the through-hole 22 (see Figure 7) is located approximately half the beam depth D of the wooden beam 21 from the lower surface 21b of the wooden beam 21. In a side view of the wooden beam 21, the through-hole 22 has a square shape, more specifically a rectangular shape. In the wooden beam 21, the portion where the beam depth is reduced due to the formation of the through-hole 22 is the through-hole forming portion 21A.

[0027] The beam structure 20 is equipped with an upper beam side reinforcing member 25 that reinforces the through-hole forming portion 21A. The upper beam side reinforcing member 25 is formed to be wider than the through-hole 22 in the beam axis direction when viewed from the side of the beam structure 20. The upper beam side reinforcing member 25 is formed in a channel-shaped cross-section. The upper beam side reinforcing member 25 is provided so as to sandwich the through-hole forming portion 21A of the wooden beam 21 from both sides in the beam width direction.

[0028] As shown in Figure 6, the upper beam side reinforcement member 25 has a side portion 26, an upper portion 27, and a lower portion 28. The side portion 26 covers the side of the wooden beam 21 above the through-hole 22. The upper portion 27 covers a portion of the upper surface 21a of the wooden beam 21 above the through-hole 22. The lower portion 28 has both ends fitted into the wooden beam 21 and its central portion covers a portion of the upper surface 22a of the through-hole 22. The upper beam side reinforcement member 25 is fixed to the wooden beam 21 by adhesive, screws, etc. (not shown). The upper beam side reinforcement member 25 is made of a material having higher strength than the wooden beam 21, such as steel.

[0029] As shown in Figure 7, when a downward distributed load w acts on the wooden beam 21, a compressive stress σ32 is generated in the upper part of the wooden beam 21 located above the penetration opening 22, while a tensile stress σ12 is generated in the lower part. Additionally, a tensile stress σ22 is generated in the lower part of the wooden beam 21 (the part on the lower surface 21b side). The stress transfer between the tensile stress σ12 and the tensile stress σ22 occurs through the corner portion 24 of the penetration opening 22. Therefore, cracks are likely to form near the corner portion 24 of the penetration opening 22.

[0030] As shown in Figure 5, in relation to the occurrence of cracks at the corner 14, the beam structure 20 is provided with a reinforcing tape 30. The reinforcing tape 30 is applied so as to straddle the corner 24. Specifically, the reinforcing tape 30 is applied so as to pass through the corner 24 and straddle one side of the wooden beam 21, the bottom surface 21b of the wooden beam 21, and the other side of the wooden beam 21. The reinforcing tape 30 is made of, for example, carbon fiber.

[0031] Furthermore, the reinforcing tape 30 only needs to be provided so as to straddle the corner portion 24. For example, the reinforcing tape 30 may be provided only near the corner portion 24. In this case, the reinforcing tape 30 may be provided in a direction that is parallel to the beam depth direction when viewed from the side, or in a direction that is perpendicular to the beam depth direction.

[0032] As shown in Figure 8, the wooden beam 21 has a reinforcing member fitting portion 32. The reinforcing member fitting portion 32 is a recess into which the end of the lower surface portion 28 of the upper beam side reinforcing member 25 is fitted. In a side view of the wooden beam 21, the reinforcing member fitting portion 32 is formed so as to extend the corner portion 24 in the direction of the beam axis by extending the upper surface 22a of the through-hole 22.

[0033] The beam structure 20 is fabricated from a wooden beam 21 having a through-hole 22 and a reinforcing member fitting section 32. Then, upper beam side reinforcing members 25 are positioned so that both ends are fitted into the reinforcing member fitting section 32. Finally, the beam structure 20 is completed when the upper beam side reinforcing members 25 are fixed to the wooden beam 21.

[0034] The operation and effects of the second embodiment will now be described. (2-1) The beam structure 20 has a wooden beam 21 and a through-hole 22 that penetrates the wooden beam 21. The through-hole 22 is located at an eccentric position below the beam in the direction of the beam's depth. The through-hole 22 is a rectangular opening in a side view of the beam structure 20.

[0035] In the beam structure 20, when applying fire-resistant coating to the wooden beam 21 using fire-resistant board material, it is only necessary to cut and process the fire-resistant board material to match the inner shape of the penetration opening 22. In other words, special manufacturing or processing methods are not required to produce the fire-resistant coating material. Furthermore, since the penetration opening 22 is eccentrically located on the lower side, the penetration opening forming portion 11A is formed only on the upper side of the penetration opening 22. This increases the rigidity of the penetration opening forming portion 21A by increasing its dimensional value in the beam depth direction. As a result, deflection of the wooden beam 21 near the penetration opening 22 can be suppressed.

[0036] (2-2) As shown in Figure 9, the beam structure 20 can be installed above the ceiling material 33. In this configuration, since the ceiling material 33 is installed below the wooden beam 21 and spaced a predetermined distance H from the lower end of the wooden beam 21, the space above the ceiling material 33 and the space of the through-hole 22 communicating with the upper part of the ceiling material 33 can be used as equipment space 34. In other words, not only the space of the through-hole 22 but also the space between the wooden beam 21 and the ceiling material 33 can be used as equipment space 34.

[0037] The second embodiment can be implemented with the following modifications. The second embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically. The beam structure 20 does not necessarily have to include at least one of the upper beam side reinforcing members 25 and the reinforcing tape 30.

[0038] The upper beam side reinforcement member 25 only needs to reinforce the through-hole forming portion 21A of the wooden beam 21. Therefore, the upper beam side reinforcement member 25 is not limited to being formed in a channel-shaped cross-section, but may also be a flat plate attached to the side of the wooden beam 21.

[0039] The side view shape of the through-hole 22 can be rectangular or, for example, trapezoidal. In this case, the through-hole 22 is formed so that a pair of parallel sides face each other in the vertical direction. Furthermore, by having the upper side of the pair of sides be the shorter side, the occurrence of cracks at the corner portion 24 can be suppressed. [Explanation of Symbols]

[0040] 10...beam structure, 11...wooden beam, 11A...penetration forming part, 11a...top surface, 11b...bottom surface, 12...penetration, 12b...bottom surface, 12c...upper open surface, 13...reinforcement fitting part, 14...corner part, 15...top reinforcement material, 17...reinforcement tape, 18...floor, 20...beam structure, 21...wooden beam , 21A...Through-hole forming part, 21a...Top surface, 21b...Bottom surface, 22...Through hole, 22a...Top surface, 24...Corner part, 25...Top beam side reinforcement, 26...Side part, 27...Top part, 28...Bottom part, 30...Reinforcement tape, 32...Reinforcement material insertion part, 33...Ceiling material, 34...Equipment space.

Claims

1. A beam structure having a wooden beam and a through-hole penetrating the wooden beam, The aforementioned through-hole is a rectangular opening that is eccentrically positioned above or below the beam-length direction of the wooden beam. Beam structure.

2. The aforementioned through-hole is provided eccentrically above the beam in the beam-length direction of the wooden beam. The beam structure has an upper reinforcing member that is provided to cover the upper surface of the through-hole and reinforces the wooden beam. The beam structure according to claim 1.

3. The aforementioned through-hole is provided eccentrically below the beam in the direction of the beam's height, The beam structure has an upper beam side reinforcing member that reinforces the beam side above the through-hole. The beam structure according to claim 1.

4. The aforementioned through-hole is provided eccentrically below the beam in the direction of the beam's height, Below the aforementioned wooden beam, ceiling material is provided at a predetermined distance from the lower end of the wooden beam. The area above the ceiling material and the through-hole communicating with the area above the ceiling material are designated as the equipment space. The beam structure according to claim 1.

5. The corners of the aforementioned through-hole are reinforced with reinforcing tape. The beam structure according to claim 1.

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