JP2656445B2 - Wood joint structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of wood used as a structural material in a building or the like, and more particularly to a joint structure of a joint portion of wood where a tensile force or a moment acts.

[0002]

2. Description of the Related Art In general, wood (for example, lumber, glulam,
In a building or the like using LVL (laminate veneer), plywood, OSB, or the like as a structural material, wood joints (for example, joints between columns and foundations, joints between columns and foundations / foundations, Joints between columns and beams, joints between beams, joints between columns, and joints between upper chords or lower chords in a truss structure, or between these upper chords and lower chords and braces At a joint or the like), a tensile force and a moment are transmitted from a mating material to which the wood is joined. Conventionally, as a joining structure for transmitting a tensile force to wood, for example, a configuration as shown in FIGS. 9 and 10 is employed.

That is, the joining structure shown in FIG.
The two steel plates 2 are brought into contact with the two parallel surfaces, and the steel plates 2 and the wood 1 are fixed by bolts 3 and these steel plates 2 are projected from the end surfaces of the wood in the length direction of the wood. After the end surface of the wood 1 is brought into contact with the mating material to be joined, the steel plate 2 is fixed to the mating material, so that the wood 1 is joined to the mating material.

In the joint structure shown in FIG. 10, a slit 4 having a predetermined depth is formed from the end face of the wood 1, a steel plate 5 is inserted into the slit 4, and the steel plate 5 and the wood 1 are connected to each other. The lumber 1 is fixed by a drift pin 6 driven from the side of the lumber 1, and the protruding portion of the steel plate 5 from the end face of the lumber 1 is fixed to the mating material, so that the lumber 1 and the mating material are joined. is there.

[0005]

By the way, such a conventional joining structure for wood is a shear joining using bolts or drift pins, but any of them has the following problems.

That is, with such a shear-bonded structure, when a tensile force acts on the wood 1, as shown in FIG. 11, the wood 1 is removed from the through hole 7 to allow the bolt 3 and the drift pin 6 to pass therethrough. Splitting fracture (R) occurs in the fiber direction, and even if the number of bolts 3 and drift pins 6 installed is increased, it is difficult to approach the total cross-sectional tensile strength inherent in the wood 1. This is the problem.

Further, in the above-described conventional joint structure, it is inevitable that play occurs between the bolt 3 or the drift pin 6 and the through hole 7.
Bolts and drift pins 6
There is also a problem that slip occurs between the wood and the wood 1 and the initial rigidity with respect to the tensile force is low. In order to increase the tensile strength and initial rigidity described above, it is necessary to increase the number of bolts 3 and drift pins 6 to be installed. In this case, not only is the construction complicated, but also the number of parts increases. This leads to higher costs.

Further, in the above-mentioned joining structure, particularly, in order to abut the end faces of the joining material not at a straight line but at a certain angle, and to join them, the steel plate 2 (5) is formed by bending according to a previously required angle. Although it is necessary to prepare the steel sheet bent at a predetermined angle in this way, the number of types of parts will increase, so the construction cost will be high as described above, and the construction itself will be It becomes complicated.

The present invention has been made in view of the above-mentioned problems in the prior art, and when a tensile force or a moment transmitted to wood acts, these external forces can be transmitted efficiently. An object of the present invention is to provide a joint structure having a simple configuration and capable of reducing the construction cost.

[0010]

In order to achieve the above-mentioned object, a wood joining structure according to claim 1 of the present invention comprises:
Joined wood, all screw bolts are screwed in a direction perpendicular to the mouth of the wood, and at least one end of the full screw bolt is provided to protrude from the end face of the joined wood, the mating material,
All the screw bolts are screwed in, and at least one end of the screw bolt is provided so as to protrude from a mating material. A plurality of insertion holes are inserted into the insertion holes of the annular member having the holes, and the protruding portions are respectively fastened with nuts in the holes of the annular member.

According to a second aspect of the present invention, in the first aspect, the end surface of the joined lumber from which all the screw bolts protrude and the annular member correspond to the curvature of the outer peripheral surface of the annular member. It is characterized by being joined via a washer having a curved surface. According to a third aspect of the present invention, in the first aspect, a curved surface corresponding to a curvature of an outer peripheral surface of the annular member is formed on an end face of the joined wood or the mating member from which all screw bolts protrude. The annular member is brought into contact with a curved surface. According to a fourth aspect of the present invention, in the first aspect, the end face of the annular member is provided with a scale indicating a circumferential angle around the axis of the annular member. I do.

[0012]

In the joint structure for wood according to the first aspect of the present invention, the threads of all the screw bolts screwed into the joined wood bite into the fibers of the joined wood to act through the full screw bolt. External force is evenly distributed and transmitted to the surrounding xylem in contact with each screw thread. Then, the external force increases and shear fracture occurs between the wooden part and the surrounding wooden part sandwiched between the screw threads, and all the screw bolts come off, so that the proof strength of the joined wood is lost. Will be Therefore, the proof stress of this joint structure is proportional to the area of attachment between the screw thread and the xylem, but since the attachment surface is formed large over the entire length of the threaded portion of the entire screw bolt, a large proof stress is obtained. Is obtained. In this case, if the screw thread bites into the xylem, there is no gap between the two, and slippage between the two when an external force is applied is suppressed, thereby securing a sufficient initial rigidity.

[0013] Further, in the joined wood and the mating material, the protruding portions of the respective screw bolts are inserted into the insertion holes of the annular member, and the protruding portions are respectively nuts in the holes of the annular member. Since it is stopped and joined, the joining surface of the joined wood and the mating material is abutted at a free angle by drilling the through hole of the annular member in advance so as to have a predetermined angle. It becomes possible to join in the state where it was set.

According to the second aspect of the present invention, the end face of the joined wood from which all the screw bolts protrude and the annular member have a curved surface corresponding to the curvature of the outer peripheral surface of the annular member. Due to the connection via the washer, the connection between the bonded wood and the annular member results in surface contact, and thus the connection is a rigid connection. According to the wood joining structure of the third aspect, a curved surface corresponding to the curvature of the outer peripheral surface of the ring member is formed on the end surface of the joined wood from which all the screw bolts protrude, and the ring member is formed on the curved surface. Since they are brought into contact with each other, the joined wood and the annular member are in surface contact, and thus the joint is a rigid joint. According to the joint structure of wood according to claim 4, since the scale indicating the circumferential angle around the axis of the annular member is provided on the end surface of the annular member, Depending on the butting angle between the material and the counterpart material, it becomes possible to produce an annular member by drilling an insertion hole at a desired angle in accordance with the scale at the construction site, and accordingly, it is possible to prepare a plurality of types of ring members in advance according to the joining angle There is no need to prepare an annular member.

[0015]

Hereinafter, the present invention will be described in detail. 1 to 3 show examples in which the wood joining structure of the present invention is applied to the joining between the upper chord (lower chord) material and the braces in a wooden truss. In these figures, reference numeral 10 denotes an upper chord material, and 11 denotes an upper chord material.
Is a lower chord material, and 12 is a brace. First, the joining between the upper chord material 10 and the brace 12 will be described.
The structure of the upper chord material 10 and the brace 12 will be described.

The upper chord material 10 is composed of a plurality of upper chord lumbers 10a in this example. As shown in FIG. 2, the upper chord lumbers 10a are joined and connected in the longitudinal direction. is there. The first chord lumber 10a has a wooden opening formed in a rectangular shape, and a hole 13 having a predetermined inner diameter is formed at a center portion of the wooden opening at a predetermined depth in a direction orthogonal to the wooden opening. Bolt 14 is screwed. Here, since the entire screw bolt 14 is screwed into the hole 13, it is naturally screwed in a direction in which its axis is perpendicular to the opening, that is, in the length direction of the fiber forming the upper chord wood 10a. ing. Further, the full screw bolt 14 is formed such that its root diameter is substantially equal to the inner diameter of the hole 13, so that the full screw bolt 14 is screwed in such a manner that the screw thread is cut into the fiber of the upper chord wood 10a. As a result, it is firmly fixed to the upper chord wood 10a.

The full threaded bolt 14 projects a predetermined length from the opening of the upper chord lumber 10a when screwed into the upper chord lumber 10a at a predetermined depth. Further, the projecting portion 1 of the full screw bolt 14
A curved surface 15 is formed in the vicinity of 4a at the tip of the first chord lumber 10a and is concavely curved symmetrically with respect to the axis of the entire screw bolt 14. The curved surface 15 is formed so as to have a semi-circular shape in a side view, and has a curvature substantially equal to a curvature of an outer peripheral surface of an annular member described later.

The upper chord materials 10a are formed by arranging such upper chord lumbers 10a so as to face each other with their mouths facing each other, and abutting and joining them through a ring member 16. Here, the annular member 16 has a cylindrical shape, and two insertion holes 16a are formed in the side wall portion thereof.
These are made of metal perforated so as to form an angle of 180 ° when the axis is centered, and the curvature of the outer peripheral surface substantially matches the curved surface 15 of the upper chord wood 10a as described above. It was done. That is, the first lumber lumber 10a, 1
0a is a protruding portion 14a of each full screw bolt 14.
Are inserted through the insertion holes 16a, 16a of the annular member 16, and the annular member 16 is clamped between the curved surfaces 15, 15 of the upper chord lumber 10a, 10a.
The whole screw bolt 14 is fastened with a nut 19 through a washer 18 inside.
Are joined by tightening the protruding portion 14a.

Here, the tensile strength in this joint structure is such that the total screw bolt 14 and the annular member 16 are rigidly connected to each other by the nuts being fixed by nuts. Determined by tensile strength.
The tensile strength between the full screw bolt 14 and the upper lumber 10a is proportional to the contact area between each screw thread of the full screw bolt 14 and the wooden part that the screw thread cuts into. That is,
When the tensile strength is T (kg / cm ² ), the shear strength of the first chord wood 10a is Fs (kg / cm ² ), the outer shape of the entire screw bolt 14 is D (cm), and the screwing depth is L (cm). The tensile strength T is obtained by the following equation. T = α ・ π ・ D ・ L ・ S

In this equation, α indicates a reduction count, and 0
<Α ≦ 1. And the first lumber wood 10a
Is a lumber, the influence of cracks due to drying is large, and thus α is small. In the case of laminated wood, LVL, etc., the cracks due to drying are extremely small.
Becomes a value close to 1. Accordingly, the first lumber lumber 10
According to the joint structure between a and 10a, a large proof strength very close to the total cross-sectional tensile strength of the upper chord wood 10a can be obtained. Moreover, since there is no gap between the wood 10 and the entire screw bolt 12, slippage or the like is eliminated, and a high initial rigidity and a linear tensile strength characteristic can be obtained.

The washer 18 has one surface curved with a curvature substantially equal to the curvature of the inner peripheral surface of the annular member 16, and the curved surface is formed on the inner peripheral surface of the annular member 16. By being arranged in contact with each other, the nut 19 is securely fastened. In such joining, the upper chord wood 10a is the joined wood in the present invention, and is also a mating material. Further, in the upper chord material 10 thus joined and formed, a cap (not shown) made of a refractory material is applied so as to cover the annular member 16 at the joint portion.
Alternatively, by filling and hardening a wet refractory material such as mortar or the like, the joint portion can be made to have a refractory structure.

As shown in FIG. 1, the upper chord member 10 formed by joining the upper chord lumbers 10a to each other has a total screw bolt 20 in a thickness direction thereof (a direction orthogonal to the full screw bolt 14). , 20 are threaded through. And these full screw bolts 2
End plates 21, 0 and 20, which protrude from the upper chord material 10, have end plates 21 which connect these protruding portions to upper ends thereof.
Are nut-fastened. In this embodiment,
The lower chord material 11 has a plurality of lower chord lumbers 1 like the upper chord material 10.
1a are joined together.

On the other hand, as shown in FIG. 3, the brace 12 has the same thread as that of the first lumber lumber 10a, and the entire screw bolt 21 is inserted in a state of being perpendicular to the edge of the lug. 22 are formed. The curved surface 22 is formed so as to be symmetrically recessed with a curvature substantially matching the curvature of the outer peripheral surface of the annular member described later. Also, on both sides of the curved surface 22, there are formed slopes 23, 23 which are cut obliquely with respect to the opening.

The upper chord material 10 and the brace 12 having such a configuration are used.
Is that the brace 12 is joined at a predetermined angle via the annular member 24 and joined. Here, the ring member 24
Has a cylindrical shape and has two insertion holes 24a
Are formed so as to form an angle of 120 °, and the curvature of the outer peripheral surface thereof substantially matches the curved surface 22 of the brace 12 as described above.

That is, as described above, the entire chord member 10 has the entire screw bolt 20 projecting from the lower surface thereof, and the annular member 24 is brought into contact with the projecting portion 20a via the end plate 25 and the washer 26. Have been. Ring member 24
Is inserted into the through hole 24a of the projecting portion 2 of the entire screw bolt 20.
0a is inserted, and the protruding portion 20a of the entire screw bolt 20 is fastened by a nut 29 via a washer 28 in a hole 27 of the annular member 24, thereby being fixed to the upper chord material 10. In addition, this annular member 24 has all the screw bolts 21 of the brace 12 inserted into the other insertion hole 24a.
The brace 12 is fixed to the ring member 24 by inserting the protruding portion 21 a of the entire screw bolt 21 with the nut 29 through the washer 28 in the hole 27 through the washer 28. . With such a configuration, the upper chord material 1
0 and the brace 12 are rigidly joined via an annular member 24.

The washer 26 has one surface curved with a curvature substantially equal to the curvature of the outer peripheral surface of the annular member 24, and the curved surface thereof contacts the outer peripheral surface of the annular member 24. They are arranged in contact with each other. Also, the washer 28, 28 has one surface curved with a curvature substantially equal to the curvature of the inner peripheral surface of the annular member 24, similar to the washer 18, and the surface on the curved side is the annular member 24. Are arranged in a state of contact with the inner peripheral surface.

In this joint structure, the tensile force acting on the brace 12 is applied to the upper chord material 10 via the entire screw bolt 20.
Is transmitted to the side surface with the compressive force of the washer 26. In this case, since the tensile strength of the brace 12 is close to the total cross-sectional tensile strength of the timber of the brace 12 itself, the brace 12 has a large tensile strength.

FIGS. 4 to 6 show examples in which the wood joining structure of the present invention is applied to a joint of lattice beams. In these figures, reference numeral 30 denotes a beam. As shown in FIGS. 5 and 6, the beam 30 is made of wood having a rectangular cross-section, and has a sharp end formed at 90 ° in a plan view on the end face side, and is further depressed at the upper end part and the lower end part on the end face side. A notch 32 having a curved surface 31 which is curved in FIG. Further, holes (not shown) are formed in the beam 30 along the length direction of the beam 30, that is, along the fiber direction of the wood, on the upper end side and the lower end side, respectively. All the screw bolts 33 are inserted in a screwed state. Each of the full screw bolts 33, 33 has one end protruding from the curved surface 31.

Then, there are four beams 30 having such a configuration.
As shown in FIG. 4, the respective cutout portions 32 are butted in a cross shape. At this time, the four notches 32 form a hole having a circular cross section by abutting the four beams 30. A ring member is formed in the hole formed by the notches 32. 34 are buried. The annular member 34 has four insertion holes 34a as shown in FIG. 6, and the angle formed by the adjacent insertion holes 34a, 34a is centered on the axis of the annular member 34. In this case, they are arranged so as to be 90 °. It is needless to say that the curvature of the outer peripheral surface of the annular member 34 matches the curvature of the curved surface of the notch 32.

The four beams 30 are formed such that the projecting portions of the respective screw bolts 33 are inserted into the insertion holes 34 of the annular member 34.
a, and the protrusions are fastened by nuts 36 via washers 35, whereby the four beams 30 are joined in a cross shape to form lattice beams. In such a lattice beam, the cruciform joint is fixed to one or a few beams 30 by tensioning or compressing the one or a few beams 30 by fastening all the screw bolts 33 with nuts via the annular member 34. Force and shear force are all screw bolt 3
3. The beam is transmitted to the remaining beams 30 via the annular member 34 and the entire screw bolt 33, and thus the joint itself becomes a rigid joint.

FIG. 7 shows an example in which the present invention is applied to a joint structure between a column and a beam in an angled ramen structure. In this figure, reference numeral 40 denotes a column, and 41 denotes a beam. These pillars 40
And the beam 41 are formed on slopes whose ends are cut at a predetermined angle with respect to the length direction of the column 40 or the beam 41, and a pair of full screw bolts 42, 42, 43, 43 are inserted in a screwed state. The pillars 40 and the beams 41 have annular members 44, 44 interposed between curved surfaces (not shown) formed in advance on the respective slopes, and the annular members 4
The projecting portions 42, 42, 43, and 43 of all the screw bolts are inserted into insertion holes (not shown) formed in the holes 4 and 44, and are joined by being nut-fastened.

FIG. 8 shows another example in which the present invention is applied to a joint structure between a column and a beam in an angled ramen structure. In this figure, reference numeral 50 denotes a column, and reference numeral 51 denotes a beam. In this example, the beams 51, 51 are joined in a state where they abut against the side surface of the column 50, and the beams 51, 51 are joined wood in the present invention, and the column 50 is a mating material. In this example, all the screw bolts 52 are projected from the end faces (slope) cut at an angle to the beams 51, 51 in the same manner as the example shown in FIG. In this way, all the screw bolts 53 are inserted, the joint surfaces of the bolts are brought into contact with each other via the annular members 54, 54, and the protruding portions of the all screw bolts 52, 53 are respectively fastened with nuts. The joint is made by.

As described above, in the joining structure in the wooden frame structure shown in FIGS. 7 and 8, the annular member 44 (5
Since all the screw bolts 42, 43 (52, 53) are fixed with nuts via 4), the column 40 (50) and the beam 41 (51) transmit a tensile force, a compressive force, and a shear force to each other. Can be fitted, so that the joint itself is a rigid joint.

In the above embodiment, a curved surface is formed on the side from which all the screw bolts 14 (21, 33) protrude, such as the first chord lumber 10a, the brace 12, the beam 30, etc. In this curved surface, the annular member 16
Although the outer peripheral surface of (24, 34) is received, the present invention is not limited to this. For example, the washer 26 shown in FIG. 1 is used, and the washer is connected between the end surface of the joined wood and the annular member. The ring member may be interposed therebetween so as to receive the outer peripheral surface of the annular member on the curved surface of the washer.

Further, as for the annular member, if a scale indicating an angle in a circumferential direction centering on the axis of the annular member is provided on an end surface of the annular member before the insertion hole is formed, it is possible to connect the joined wood with the annular member. Depending on the butt angle with the counterpart material, it is possible to produce an annular member by drilling an insertion hole at a desired angle according to the scale at the construction site, and therefore, it is possible to prepare a plurality of types of circles in advance according to the joining angle There is no need to prepare a ring member. Furthermore, if the position of the insertion hole can be seen from the end face by painting the scale corresponding to the position where the insertion hole was drilled, etc., it is easy to extrapolate the insertion hole to the projected part of all screw bolts And the workability is improved.

[0036]

As described above, according to the first aspect of the present invention, there is provided a wood joining structure according to the first aspect of the present invention, wherein the threads of all the screw bolts screwed into the joined wood bite into the fibers of the joined wood. External force acting through the bolt,
Since it is designed to be evenly distributed and transmitted to the surrounding wooden part in contact with each screw thread, a joining structure with sufficient tensile strength is obtained by increasing the thickness and screwing length of all screw bolts. Therefore, strength design and rigidity design that effectively utilize the cross-sectional area of the wood can be made possible. In addition, in this joint structure, not only the tensile strength but also the compressive strength can be obtained similarly, so that it can be sufficiently applied to a rigid frame joint structure that transmits a moment. Can be simultaneously transmitted by all the screw bolts, so that the present invention can be applied to any joining structure of a wooden structure.

In addition, the joint wood and the mating material are inserted such that the projecting portions of all the screw bolts are inserted into the insertion holes of the annular member, and the projecting portions are respectively nuts in the holes of the annular member. Since it is stopped and joined, the end faces of the joined wood and the mating material are butted at a free angle by drilling the insertion hole of the annular member at a predetermined angle in advance. It can be joined in a state where it is set.
Therefore, it is possible to cope with various butting angles simply by preparing an annular member in which only the positions of the insertion holes are matched, without preparing a plurality of types of steel plates or the like according to the butting angle in advance as in the related art. Accordingly, the construction cost can be reduced, and the construction can be prevented from becoming complicated. In addition, since the entire screw bolt is embedded in the joining wood or the mating material, it is possible to design a fire resistant by burning allowance. Further, for example, by covering the surface of the annular member with a refractory material, the joining structure itself is provided. Can have a refractory structure.

According to the second aspect of the present invention, the end face of the joined wood from which all the screw bolts protrude and the annular member are interposed via a washer having a curved surface corresponding to the curvature of the outer peripheral surface of the annular member. As a result, the joint between the joined lumber and the annular member can be brought into surface contact, and thus the joint can be a rigid joint. In the wood joining structure according to the third aspect, a curved surface corresponding to the curvature of the outer peripheral surface of the annular member is formed on an end face of the joined wood from which all screw bolts protrude, and the annular member abuts on the curved surface. Because of the stiffness, it is possible to make a surface contact between the joined lumber and the annular member, and thus the joint can be made a rigid joint. In the joint structure for wood according to claim 4, since a scale indicating a circumferential angle around the axis of the annular member is provided on an end surface of the annular member, for example, the joint wood and the mating member are provided. Depending on the butt angle with the material, the insertion hole can be drilled at the desired angle in accordance with the scale at the construction site to produce a ring member, and accordingly, a plurality of types of ring members can be prepared in advance according to the joining angle. There is no need to prepare
Higher construction costs due to an increase in the number of parts can be suppressed.

[Brief description of the drawings]

FIG. 1 is a front view showing one embodiment in which a wood joining structure of the present invention is applied to a wooden truss.

FIG. 2 is a sectional side view of a main part showing a joint structure between upper chord woods.

FIG. 3 is an enlarged view of a main part showing a joint structure between the upper chord material and the braces.

FIG. 4 is a plan view showing one embodiment in which the wood joining structure of the present invention is applied to a lattice beam.

FIG. 5 is an enlarged cross-sectional view taken along the line AA of FIG. 4;

FIG. 6 is a partially exploded perspective view of the wood structure shown in FIG. 4;

FIG. 7 is a front view showing an example of a case where the wood joining structure of the present invention is applied to a mountain-shaped ramen structure.

FIG. 8 is a front view showing another example in which the wood joining structure of the present invention is applied to a mountain-shaped ramen structure.

FIG. 9 is an external perspective view of a main part showing an example of a conventional wood joining structure.

FIG. 10 is an external perspective view of a main part showing an example of a conventional wood joining structure.

FIG. 11 is an external perspective view showing a split state in a conventional wood joining structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Upper chord material 10a Upper chord wood 11 Lower chord material 12 Brace 14, 20, 21, 33, 42, 43, 52, 53
Full screw bolts 15, 22, 31 Curved surfaces 16, 24, 34, 44, 54
Ring members 16a, 24a, 34a
Insertion hole 40, 50 Pillar 41, 51 Beam

 ──────────────────────────────────────────────────続 き Continued on the front page (73) Patent owner 591030330 Keiyo Co., Ltd. 8-9-8 Hanahata, Adachi-ku, Tokyo (73) Patent owner 000000147 ITOCHU Corporation 4-4-1 Kutaro-cho, Chuo-ku, Osaka-shi, Osaka No. 3 (73) Patent Holder 591163742 ITOCHU Construction Materials Co., Ltd. 3-6-1 Nihonbashi Honcho, Chuo-ku, Tokyo (74) The above four agents Patent Attorney Hiroshi Arafune (72) Inventor Shuhei Hirai Shinjuku-ku, Tokyo 530-14 Waseda Tsurumakicho Kosaka Building 3F, Hirai Design Studio Co., Ltd. Examiner Kazuko Nagashima (56) References JP-A-52-56714 (JP, A) Jikai Sho 54-43206 (JP, U)

Claims (4)

(57) [Claims] 1. A joined structure of wood composed of joined wood used as a structural material and a mating material joined thereto, wherein the joined wood has a total screw bolt screwed in a direction orthogonal to the opening of the wood. And at least one end of the full screw bolt is provided so as to protrude from the end face of the joined wood, and the counterpart material is provided with the full screw bolt screwed in and at least one end of the screw bolt protruding from the counterpart material. The joint wood and the mating material, the projecting portion of each full screw bolt is inserted through the insertion hole of the annular member having a plurality of insertion holes in the side wall of a cylindrical shape, and A joint structure for wood, wherein each of the protruding portions is fixed with a nut in a hole of the annular member. 2. The joining structure for wood according to claim 1, wherein the end surface of the joined wood from which all the screw bolts protrude and the annular member have a curved surface corresponding to the curvature of the outer peripheral surface of the annular member. A wood joining structure characterized by being joined via a set washer. 3. The joining structure for wood according to claim 1, wherein a curved surface corresponding to a curvature of an outer peripheral surface of the annular member is formed on an end surface from which the screw bolt of the joined wood projects.
A joining structure for wood, wherein the annular member is brought into contact with the curved surface. 4. The joining structure for wood according to claim 1, wherein a scale indicating an angle in a circumferential direction about an axis of the annular member is provided on an end surface of the annular member. Wood joining structure.