Reinforcement structure

Abstract

To provide a wooden beam reinforcement structure capable of preventing cracking in a fiber direction with a simple structure.SOLUTION: A wooden beam has a through-hole 2 penetrating in a beam width direction. In a load support 10 of the wooden beam, a plurality of machine screws 3 which are rod-like reinforcements are arranged so as to intersect the fiber direction of the load support 10 toward the inside of the load support 10 from an upper side or a lower side in the beam depth direction of the wooden beam. When seen from the extending direction of the through-hole 2, the machine screws 3 form a polygonal closed region surrounding the through-hole 2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a reinforcing structure for a wooden beam. [Background technology]

[0002] Many equipment pipes are installed in the ceiling space or under the ceiling of a building, and through holes are often provided in steel beams and RC (reinforced concrete) beams to allow the equipment pipes to pass through. If the size of the through hole is large compared to the beam depth, the area around the through hole is reinforced.

[0003] In recent years, laminated timber, a type of wood material, has been used as a structural member not only for low-rise buildings but also for mid- and high-rise buildings, and the cross-section of the members is becoming larger. Wooden beams made of laminated timber are generally fitted without through holes, since providing through holes can cause brittle splitting failure and effective reinforcement methods for through holes have not been established.

[0004] On the other hand, Patent Document 1 describes a reinforcing structure for a through hole of a wooden beam in which a steel pipe is inserted into the through hole of the wooden beam and vertical bolts are provided on both sides of the through hole to fasten the wooden beam in the vertical direction. Patent Document 2 describes a structure in which lag screws are provided to surround the periphery of the through hole of the wooden beam and to bear the shear force around the through hole. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-209856 [Patent Document 2] Patent No. 6482224 Summary of the Invention [Problem to be solved by the invention]

[0006] The reinforcing structure of Patent Document 1 aims to achieve the same performance as when there is no cross-sectional defect in the wooden beam by inserting a steel pipe into the through hole, but the primary purpose is not to prevent the above-mentioned splitting failure.

[0007] In addition, in the reinforcement structure of Patent Document 2, the lag screws are installed from the top surface of the wooden beam, so the lag screws surrounding the lower side of the through hole are longer than necessary, which could lead to increased construction work and increased costs.

[0008] The present invention has been made in consideration of the above problems, and its object is to provide a reinforcement structure etc. that can prevent cracking of wooden beams with a simple configuration. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the present invention is a reinforcing structure for a wooden beam having a through hole penetrating in the beam width direction, wherein a plurality of rod-shaped reinforcing parts are arranged from the upper and lower sides of the wooden beam in the beam depth direction toward the inside of the wooden beam, and when viewed from the extension direction of the through hole, the multiple reinforcing parts form a polygonal closed area surrounding the through hole.

[0010] In the present invention, a rod-shaped reinforcing portion is disposed inside the wooden beam. The rod-shaped reinforcing portion mainly resists tension, preventing the wooden beam from cracking. Furthermore, since a plurality of reinforcing portions are disposed to form a closed area surrounding the through hole, cracking of the wooden beam does not progress from a portion where there is no reinforcing portion. Furthermore, since the reinforcing portions are provided from both the upper and lower sides of the wooden beam, a reinforcing portion longer than necessary is not required to surround the lower side of the through hole, as described above. As a result, the present invention can prevent cracking of the wooden beam with a simple configuration.

[0011] The reinforcing portion is arranged, for example, so as to intersect with the fiber direction of the wooden beam. Since wood materials are prone to cracking in the direction of the grain, by arranging the reinforcing parts so as to intersect with the direction of the grain, cracking in the direction of the grain can be effectively prevented.

[0012] When viewed from the extension direction of the through hole, the closed region is, for example, line-symmetric with respect to a reference line in the beam depth direction that passes through the center of the cross section of the through hole. This provides a balanced reinforcement around the through hole, providing a high reinforcement effect.

[0013] When viewed along the beam width direction, the reinforcing portion may be disposed obliquely with respect to the beam depth direction. This allows the fixing length of the reinforcing portion to be increased.

[0014] The reinforcing portion is, for example, a screw. Alternatively, it is also preferable that the reinforcing portion is formed by inserting a steel rod into a hole formed in the wooden beam and filling the hole with a filler material. The former requires a relatively small screw diameter and can be screwed directly into the wooden beam, making installation easy. The latter allows for a relatively long reinforcing section to be installed easily and its length can be set as desired.

[0015] It is also desirable that the cross section of the through hole is circular, and the closed area is a polygon having six or more corners. The reinforcing effect is enhanced by making the shape of the closed region a polygon with six or more corners and making the shape closer to the circle of the through hole. Effect of the Invention

[0016] According to the present invention, it is possible to provide a reinforcing structure for a wooden beam that can prevent cracking of the wooden beam with a simple configuration. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 shows a wooden beam 1. [Diagram 2] A diagram showing the reinforcing structure using screws 3. [Diagram 3] FIG. 4 is a diagram showing a reinforcing structure using a reinforcing portion 3a. [Figure 4] FIG. 13 is a diagram showing a hexagonal closed region. [Diagram 5] FIG. 13 is a diagram showing an octagonal closed region. [Figure 6] An example of installing screw 3 at an angle to the beam depth direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0019] Fig. 1 is a perspective view showing a wooden beam 1 according to an embodiment of the present invention. The wooden beam 1 is a beam member made of wooden material with a fire-retardant layer 20 provided on the side and bottom surfaces in the beam axis direction of the load-supporting part 10, and the cross section perpendicular to the beam axis direction is rectangular. Note that the fire-retardant layer 20 is omitted on the top surface of the load-supporting part 10 because it contacts a concrete slab (not shown) or the like, but in some cases the fire-retardant layer 20 may be provided on the top surface.

[0020] The wooden beam 1 is provided with a through hole 2 that penetrates the wooden beam 1 in the beam width direction. The through hole 2 is for passing equipment piping and the like, and in this embodiment is formed at the center of the wooden beam 1 in the beam depth direction, and has a circular cross section. The beam width direction is the direction perpendicular to the beam axial direction and the beam depth direction. The beam axial direction corresponds to the left-right direction in FIG. 1, and the beam depth direction corresponds to the up-down direction in FIG. 1. The beam width direction corresponds to the depth direction in FIG. 1.

[0021] The load-bearing part 10 is the main body part of the wooden beam 1 that mainly bears the load, and is made of laminated wood or the like with the fiber direction in the beam axis direction. However, the load-bearing part 10 is not limited to this, and other wooden materials (such as CLT) with the fiber direction in the beam axis direction or beam depth direction may also be used.

[0022] The fire-retardant layer 20 is a part for stopping the combustion of the wooden beam 1 in the event of a fire, and is made of, for example, wood material impregnated with a fire-retardant agent, but is not limited to this. It is also possible to provide a substitute fire layer or decorative material made of wood on the outside of the fire-retardant layer 20.

[0023] 2(a) shows a cross section of the load-bearing part 10 of the wooden beam 1 in the beam depth direction along the beam axis direction. In this embodiment, the periphery of the through hole 2 is reinforced using a plurality of screws 3, which are rod-shaped reinforcing parts, thereby preventing cracking in the fiber direction of the load-bearing part 10. The screws 3 around the through hole 2 constitute the reinforcing structure 100 of the present invention.

[0024] In this embodiment, four screws 3 are driven into the load-bearing portion 10 so as to intersect with the fiber direction (beam axis direction) of the load-bearing portion 10, and these screws 3 are arranged so as to surround the through hole 2 when the load-bearing portion 10 is viewed from the extension direction of the through hole 2 (corresponding to the normal direction to the paper surface in Figure 2(a)).

[0025] Of these, two screws 3 are driven diagonally downward from the upper side of the beam depth direction of the load support part 10 toward the inside of the load support part 10 so as to intersect in an X shape when viewed from the extension direction of the through hole 2, and are arranged so that the parts below the intersection surround the upper side of the through hole 2. The heads of these screws 3 are embedded in the top surface of the load support part 10 and do not protrude upward from the top surface.

[0026] The remaining two screws 3 are driven diagonally upward from the lower side of the beam depth direction of the load support part 10 toward the inside of the load support part 10 so as to intersect in an X shape when viewed from the extension direction of the through hole 2, and are arranged so that the parts above the intersection surround the lower side of the through hole 2. The heads of these screws 3 are also embedded in the bottom surface of the load support part 10 and do not protrude downward from the bottom surface.

[0027] When viewed from the extension direction of the through hole 2, the tip of the screw 3 driven from below intersects with the tip of the screw 3 driven from above on each side of the beam axis direction of the through hole 2. As a result, when viewed from the extension direction of the through hole 2, the four screws 3 form a rectangular (diamond-shaped) closed area surrounding the through hole 2.

[0028] Fig. 2(b) is a cross section of the load support part 10 in the beam width direction taken along line AA in Fig. 2(a). In this embodiment, a pair of the above-mentioned reinforcing structures 100 are arranged at an interval in the beam width direction at the middle part in the beam width direction. However, the number and positions of the reinforcing structures 100 are not limited to this. Also, the screws 3 in each reinforcing structure 100 are arranged with their positions shifted in the beam width direction as necessary to prevent interference.

[0029] Fig. 2(a) is a cross-section of the load-bearing part 10 taken along line BB in Fig. 2(b). As shown in Fig. 2(a), the closed area formed by the screws 3 is symmetrical with respect to the reference lines h and v in the beam axis direction and beam depth direction that pass through the center C of the cross-section of the through hole 2, so that the area around the through hole 2 is reinforced in a well-balanced manner.

[0030] As described above, in this embodiment, the screw 3 is placed inside the load-bearing part 10 of the wooden beam 1 so as to intersect with the fiber direction of the load-bearing part 10 of the wooden beam 1. The screw 3 mainly resists tension, and prevents cracking in the fiber direction of the load-bearing part 10. In this embodiment, the head of the screw 3 is embedded in the load-bearing part 10, so it is also possible to resist tension by pressure from the head, and the length of the threaded part of the screw 3 can be shortened accordingly.

[0031] Furthermore, since a plurality of screws 3 are arranged to form a closed region surrounding the through hole 2, cracking in the fiber direction will not progress from areas where there are no screws 3. Furthermore, since the screws 3 are provided from both the upper and lower sides of the load support portion 10, screws 3 that are longer than necessary are not required to surround the lower side of the through hole 2, as described above.

[0032] As described above, in this embodiment, a simple configuration can be used to prevent cracking in the fiber direction of the load-bearing part 10 of the wooden beam 1, and the hurdle of forming a through hole 2 in the wooden beam 1 is lowered, thereby increasing the freedom in arranging equipment piping, etc., leading to effective use of the space above the ceiling and reduced environmental impact by promoting the use of wood materials.

[0033] In addition, in this embodiment, the closed area formed by the screw 3 is symmetrical with respect to each of the reference lines h and v in the beam axis direction and beam depth direction passing through the center C of the cross section of the through hole 2, so that the area around the through hole 2 is reinforced in a well-balanced manner, resulting in a high reinforcing effect.

[0034] However, the present invention is not limited to the above embodiment. For example, the screw 3 of this embodiment can be relatively small in diameter and can be directly screwed into the load-bearing portion 10 of the wooden beam 1, so that it is easier to install than the above-mentioned lag screw, which has a relatively large diameter and requires the formation of a pilot hole during installation. However, the member used to reinforce the through hole 2 is not limited to this.

[0035] For example, as shown in a reinforcement structure 100a in Fig. 3, a rod-shaped reinforcing part 3a may be replaced with a structure similar to a GIR (Glued in Rod) joint in which a steel rod 31 is inserted into a hole 11 formed in a load-bearing part 10 of a wooden beam 1 and a filler 32 such as an adhesive is filled into the hole 11. In the example in Fig. 3, a through hole 2 is formed in a position toward the upper side, away from the center in the beam depth direction of the load-bearing part 10. Therefore, the length of the reinforcing part 3a formed from the upper side in the beam depth direction of the load-bearing part 10 is different from the length of the reinforcing part 3a formed from the lower side, with the latter reinforcing part 3a being longer.

[0036] Since the reinforcing portion 3a can be formed to be relatively long, even when the through hole 2 is located off-center in the beam depth direction or the wooden beam 1 has a large cross section and reinforcement with prefabricated screws 3 is not possible, the long reinforcing portion 3a can be easily constructed. The length of the reinforcing portion 3a can be set arbitrarily (within a range not exceeding an upper limit), and the length of the reinforcing portion 3a can be kept to a necessary minimum. In the example of Figure 3, the closed region formed by the four reinforcing portions 3a is line-symmetrical with respect to the reference line v in the beam depth direction that passes through the center C of the cross section of the through hole 2, and in this case too, the periphery of the through hole 2 is reinforced in a well-balanced manner, providing a high reinforcing effect.

[0037] In this embodiment, four screws 3 are used to form a rectangular closed area around the through hole 2, but the number and arrangement of the screws 3 are not limited to this. For example, as shown in the reinforcement structure 100b of Fig. 4, two screws 3 may be added that are driven vertically from above and below the beam depth direction of the load support part 10, so that a hexagonal closed area is formed around the through hole 2. These two screws 3 are arranged on both sides of the through hole 2 in the beam axis direction within the load support part 10.

[0038] Furthermore, as shown in the reinforcement structure 100c of Figure 5, two screws 3 are driven diagonally downward from the upper side of the beam depth direction of the load support part 10 on both sides of the beam axis direction of the through hole 2, and two screws 3 are driven diagonally upward from the lower side of the beam depth direction of the load support part 10 on both sides of the beam axis direction of the through hole 2, so that the tips of the screws 3 driven from above and the tips of the screws 3 driven from below intersect on both sides of the beam axis direction of the through hole 2, forming an octagonal closed area around the through hole 2.

[0039] In this way, the reinforcing effect can be increased by increasing the number of corners of the polygon of the closed area formed by the screws 3 to six or more and making the shape closer to the circle of the through hole 2. This is also true for the reinforcing part 3a described above, but since there is a risk of cracks occurring near the through hole 2 when drilling the hole 11 in the load support part 10, it is more desirable to use the screws 3 when forming a polygonal closed area with a large number of corners as shown in Figures 4 and 5.

[0040] In this embodiment, as shown in Fig. 2(b), when the load support portion 10 is viewed along the beam width direction, the screws 3 are provided along the beam depth direction, but as shown in the reinforcement structure 100d in Fig. 6, when the load support portion 10 is viewed along the beam width direction, the screws 3 may be arranged so as to be inclined with respect to the beam depth direction. This makes it possible to increase the fixing length of the screws 3 and improve the fixing property of the screws 3. The same applies to the reinforcing portion 3a.

[0041] In this embodiment, the cross section of the through hole 2 is circular, but the cross-sectional shape of the through hole 2 is not limited to this, and may be rectangular or the like. In this case, the screws 3 and the like are provided from above and below the load support portion 10 so as to surround the through hole 2. In this embodiment, the extension direction of the through hole 2 is a direction perpendicular to the beam axis direction and the beam depth direction, but the extension direction of the through hole 2 may be inclined from said directions.

[0042] Furthermore, since cracks in wooden materials tend to occur in the direction of the fibers of the wooden materials, in this embodiment, cracks in the direction of the fibers can be suitably prevented by arranging the screws 3 etc. so as to intersect with the direction of the fibers of the load-supporting portion 10 of the wooden beam 1. On the other hand, depending on the type of wooden material, there may be cases where there is no clear direction of the fibers, and even in this case, the screws 3 etc. are effective in preventing cracks in the wooden material.

[0043] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to such an example. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the technical ideas disclosed in this application, and it is understood that such examples also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0044] 1: Wooden beam 2:Through hole 3: Vis 3a: Reinforcement section 10: Load support part 11: Hole 20: Fire-retardant layer 31: Steel rod 32: Filling material 100, 100a, 100b, 100c, 100d: Reinforced structure

Claims

1. A reinforcement structure for a wooden beam having a through hole penetrating in the beam width direction, A plurality of rod-shaped reinforcing parts are arranged from the upper and lower sides of the wooden beam in the beam depth direction toward the inside of the wooden beam, A reinforcement structure, characterized in that, when viewed from the extension direction of the through hole, the multiple reinforcing portions form a polygonal closed area surrounding the through hole.

2. The reinforcement structure according to claim 1, characterized in that the reinforcing portion is arranged so as to intersect with the fiber direction of the wooden beam.

3. 2. The reinforcing structure according to claim 1, wherein, when viewed from the extension direction of the through hole, the closed region is symmetrical with respect to a reference line in the beam depth direction passing through the center of the cross section of the through hole.

4. 2. The reinforcing structure according to claim 1, wherein the reinforcing portion is disposed obliquely with respect to the beam depth direction when viewed along the beam width direction.

5. 2. The reinforcing structure according to claim 1, wherein the reinforcing portion is a screw.

6. 2. The reinforcement structure according to claim 1, wherein the reinforcing portion is formed by inserting a steel rod into a hole formed in the wooden beam and filling the hole with a filler material.

7. 2. The reinforcement structure according to claim 1, wherein the cross section of the through hole is circular, and the closed area is a polygon having six or more corners.

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