Column-beam connection structure and manufacturing method thereof

Abstract

To provide a column-beam connection structure formed through connection of wooden member to each other, with high rigidity even when no auxiliaries such as a connection jig and a connection metal is used.SOLUTION: A column-beam connection structure is configured to connect a wooden member A and a wooden member B to each other in a state those fiber directions are orthogonal to each other, the column-beam connection structure being configured to connect a finger part FA formed on an end surface of the wooden material A and a finger part FB formed on a flat grain surface or a regular grain surface of the wooden material B though a finger joint, wherein the fiber direction of the wooden material A is orthogonal to a groove direction of the finger part FA, the fiber direction of the wooden material B is parallel to the groove direction of the finger part FB, and one of the wooden material A and the wooden material B is a column, and the other is a beam.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a beam-column joint structure using finger joints and a manufacturing method thereof. [Background technology]

[0002] The joints between columns and beams are an important element in ensuring the earthquake resistance of wooden buildings. The types of joints are roughly divided into (i) mechanical joints, which use joints or metal fittings to form the joint, (ii) Japanese-style joints that form a joint by combining pieces of wood, and (iii) joints that glue wooden members together directly or via adhesive. (i) mechanical joints use joints such as nails and bolts, so their strength depends on the material properties of the parts that make up the joint, and they have been widely used in recent wooden buildings. (ii) Japanese-style joints are made by processing wood and combining it, and the joint is basically completed by fitting without the need for auxiliary joints such as metal fittings. Many traditional wooden buildings are made using this type of joint. Today, it is often used with reinforcing metal fittings because it may not be strong enough, but it is still indispensable. (iii) adhesive joints may be used in combination with other joints. When gluing pieces of wood together, it is said that the adhesive strength is stronger when the grain direction is parallel than when it is perpendicular.

[0003] Currently, most joints in wooden buildings are made using (i) joints or metal joints. In addition, (ii) Japanese-style joints are still used in general wooden houses. However, when joints of (i) or (ii) are used, the cost is high, and when cheap joints or metal joints or Japanese-style joints are used, sufficient rigidity cannot be obtained. On the other hand, (iii) adhesive joints are not used much. In particular, in joints that join columns and beams, etc., the grain direction of the wood is not parallel but perpendicular, so it is almost impossible to bond them with adhesives alone. However, (iii) adhesive joints are lightweight and environmentally friendly. Furthermore, if the adhesive strength between columns and beams can be improved, the rigidity of the joints may be greatly improved.

[0004] Incidentally, a method of gluing using finger joints is used to join the ends (buttocks) of small pieces of wood that make up a laminated timber (Patent Document 1). In addition, Non-Patent Document 1 describes a "90-degree finger joint joint specimen" in which a base material (21) made of two laminated timber pieces is joined to a joint (22) made of laminated timber by a finger part (23) as shown in FIG. 16. However, the angle between the fiber direction of the base material (21) and the fiber direction of the joint (22) is 135°, and the buttocks of the base material (21) and the joint (22) are joined together. Non-Patent Document 1 does not describe directly joining base materials (21) whose fiber directions are perpendicular to each other using finger joints. In addition, the specimen described in Non-Patent Document 1 uses a relatively large finger joint with a finger length t2 of 50 mm, called a "big finger joint." [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2-9601 [Non-patent literature]

[0006] [Non-Patent Document 1] "Experimental Study on Moment Resisting Joints of Glulam with Finger Joints" Journal of Architecture, Architectural Institute of Japan, Vol. 514, p163-168, December 1998 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve the above-mentioned problems, and has an object to provide a column-beam joint structure having high rigidity, which is made by joining together wood pieces whose fiber directions are perpendicular to each other. [Means for solving the problem]

[0008] The above problem is solved by providing a column-beam joint structure in which wooden material A and wooden material B are joined so that their grain directions are perpendicular, in which a finger part FA formed on the end surface of wooden material A and a finger part FB formed on the flat grain surface or straight grain surface of wooden material B are joined with a finger joint, in which the grain direction of wooden material A is perpendicular to the groove direction of finger part FA and the grain direction of wooden material B is parallel to the groove direction of finger part FB, and one of wooden material A and wooden material B is a column and the other is a beam.

[0009] In this case, it is preferable that the finger portion FA and the finger portion FB are joined by a finger joint via an adhesive. It is also preferable that the column-beam joint structure is further formed by fastening the wooden material A and the wooden material B with a bolt.

[0010] The above problem can also be solved by providing a manufacturing method for the beam-column joint structure, in which an adhesive is applied to at least one of the finger portions FA and FB, and then the adhesive is cured while pressing the finger portions FA and FB in a state where the finger portions FA and FB are engaged with each other. In this case, it is preferable to cure the adhesive by pressing the finger portions FA and FB in a state where the finger portions FA and FB are engaged with each other by fastening the finger portions FA and FB with a bolt. Effect of the Invention

[0011] The column-beam joint structure of the present invention, in which wood pieces whose grain directions are perpendicular to each other are joined, has high rigidity even without the aid of connectors, metal connectors, etc. According to the manufacturing method of the present invention, such a column-beam joint structure can be easily obtained. [Brief description of the drawings]

[0012] [Figure 1] 1 is a photograph showing a state in which wooden material A and wooden material B are joined in Example 1. [Diagram 2] 2 is an enlarged photograph of finger portions FA and FB in FIG. 1. [Diagram 3] 2 is a schematic diagram of finger portions FA and FB in a mated state as viewed from the groove direction in the first embodiment. FIG. [Figure 4] 1 is a drawing of wood material A and wood material B in Examples 1 and 2 and Comparative Example 1. [Diagram 5] This is a drawing of the column-beam joint structure set in a horizontal load frame in Example 1. [Figure 6] FIG. 2 is a diagram showing the mounting positions of displacement gauges in the moment application test carried out in Example 1. [Figure 7] 1 is a photograph of a beam-column joint structure in which lateral tensile failure occurred in Example 1. [Figure 8] FIG. 2 is a schematic diagram showing a beam-column joint structure split by lateral tensile failure in Example 1. [Figure 9] 1 is an example of a "true rotation angle-moment diagram" obtained from a moment loading test of a column-beam joint structure in Example 1. [Figure 10] 13 is a “true rotation angle-moment diagram” obtained from a moment loading test of a column-beam joint structure in Example 2. [Figure 11] 1 is an example of a "true rotation angle-moment diagram" obtained from a moment load test of a column-beam joint structure in Comparative Example 1. [Figure 12]1 is a graph showing the initial rotational rigidity of beam-column joint structures obtained from moment loading tests in Examples 1 and 2 and Comparative Example 1. [Figure 13] 1 is a graph showing the maximum moment of the beam-column joint structures obtained from moment loading tests in Examples 1 and 2 and Comparative Example 1. [Figure 14] 1 is a graph showing structural characteristic coefficients of beam-column joint structures obtained from moment loading tests in Examples 1 and 2 and Comparative Example 1. [Figure 15] This is a photograph taken of a column-beam joint structure in which shear failure occurred at the bolt position in Comparative Example 1. [Figure 16] This is a schematic diagram of a 90-degree finger joint test specimen described in "Journal of the Architectural Institute of Japan, Structural Engineering, No. 514, pp. 163-168, December 1998." DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention is a column-beam joint structure in which wooden materials A and B are joined so that their fiber directions are perpendicular to each other, and a finger part FA formed on the end surface of wooden material A and a finger part FB formed on the flat grain surface or straight grain surface of wooden material B are joined with a finger joint, the fiber direction of wooden material A is perpendicular to the groove direction of finger part FA, the fiber direction of wooden material B is parallel to the groove direction of finger part FB, and one of wooden materials A and B is a column and the other is a beam. Conventionally, it has been said that it is difficult to bond wooden materials whose fiber directions are perpendicular to each other. In contrast, in the present invention, a highly rigid column-beam joint structure is obtained by joining wooden materials A and B whose fiber directions are perpendicular to each other with a finger joint.

[0014] The present invention will be described in more detail below with reference to the drawings. Fig. 1 is a photograph of the state in which wooden material A (1) and wooden material B (2) are joined in Example 1 described later, and Fig. 2 is a photograph of the finger part FA (3) and finger part FB (4) in Fig. 1 enlarged. Fig. 3 is a schematic diagram of the finger part FA (3) and finger part FB (4) in the engaged state as viewed from the groove direction in Example 1 described later. The column-beam joint structure of the present invention is formed by joining wooden material A (1) and wooden material B (2) so that their fiber directions (5), (7) are perpendicular to each other, and one of the wooden material A (1) and wooden material B (2) is a column and the other is a beam.

[0015] As the wood material A(1) and the wood material B(2), structural wood materials that are generally used as pillars and beams are used. Examples include laminated lumber, LVL (laminated veneer lumber), and lumber (including solid wood). The wood material A(1) and the wood material B(2) may be coniferous or broad-leaved trees. Examples of coniferous trees include cedar, cypress, larch, Japanese larch, Dommatsu, Japanese pine, red pine, red spruce, Yezo spruce, Scots pine, Japanese cypress, spruce, and black pine, while examples of broad-leaved trees include birch, oak, ash, zelkova, sugar maple, and oak. The wood material A(1) and the wood material B(2) may be of the same species or different species, but the former is preferred.

[0016] The shapes of the wood material A(1) and the wood material B(2) may be columnar, specifically, prismatic such as triangular prism, square prism, pentagonal prism, hexagonal prism, etc., cylindrical, etc., with a square prism and cylindrical shape being preferred, and a square prism being more preferred. Usually, the longitudinal direction of the wood material A(1) is the fiber direction (5) of the wood material A(1), and the longitudinal direction of the wood material B(2) is the fiber direction (7) of the wood material B(2). Therefore, if the wood material A(1) and the wood material B(2) are joined so that their longitudinal directions are perpendicular to each other, their fiber directions will also be perpendicular to each other.

[0017] A finger portion FA (3) is formed on at least one of the butt surfaces at both ends of the wooden piece A (1). The groove direction (6) of the finger portion FA (3) formed on the butt surface is perpendicular to the fiber direction (5) of the wooden piece A (1). The butt surface on which the finger portion FA (3) is formed is preferably a plane perpendicular to the fiber direction (5) of the wooden piece A (1). The position and shape of the finger portion FA (3) on the butt surface may be appropriately adjusted according to the shapes of the wooden piece A (1) and the wooden piece B (2) and the use of the column-beam joint structure. In order to further increase the rigidity of the column-beam joint structure, it is preferable that the finger portion FA (3) is formed on the entire butt surface as shown in FIG. 1.

[0018] At least one finger portion FB(4) is formed on the cross-grain or straight-grain surface of the wooden material B(2). Both the cross-grain and straight-grain surfaces are preferably flat surfaces parallel to the grain direction (7) of the wooden material B(2). The finger portion FB(4) is formed on the cross-grain or straight-grain surface of the wooden material B(2) so that the groove direction (8) of the finger portion FB(4) is parallel to the grain direction (7) of the wooden material B(2). The position and shape of the finger portion FB(4) on the cross-grain or straight-grain surface may be appropriately adjusted according to the shapes of the wooden material A(1) and the wooden material B(2) and the use of the column-beam joint structure.

[0019] The greatest feature of the present invention is that the finger part FB (4) is formed on the flat or straight grain surface of the wooden material B (2) so that the fiber direction (7) and the groove direction (8) are parallel. Usually, in a joint joint for joining a column and a beam, the fiber directions are perpendicular to each other, but even if the surfaces whose fiber directions are perpendicular are bonded with an adhesive, sufficient adhesive strength cannot be obtained, and it has been impossible to obtain a highly rigid column-beam joint structure by such a joining method. However, a joint formed by adhesive is lightweight and is also excellent in terms of the environment. Furthermore, if the adhesive strength between the column and the beam can be improved, the rigidity of the joint may be greatly improved. For this reason, the inventors have intensively studied how to improve the rigidity of a column-beam joint structure formed by bonding a column and a beam, and have surprisingly found that the rigidity of the column-beam joint structure is significantly improved by forming a predetermined finger part FB (4) on the flat or straight grain surface of the wooden material B (2), engaging and bonding it with the finger part FA (3) formed on the butt surface of the wooden material A (1) to form a finger joint.

[0020] From the viewpoint of further improving the rigidity of the beam-column joint structure, the pitch t1 (distance between adjacent fingers) of the finger portions FA (3) and FB (4) is preferably 1 to 10 mm. The pitch t1 is more preferably 2 mm or more. Meanwhile, the pitch t1 is more preferably 5 mm or less, and even more preferably 4 mm or less. From the same viewpoint, the length t2 of the fingers in the finger portion FA (3) is preferably 1 to 50 mm. The length t2 is more preferably 2 mm or more, even more preferably 3 mm or more, and particularly preferably 5 mm or more. Meanwhile, the length t2 is more preferably 30 mm or less, and even more preferably 20 mm or less. The shape of the fingers when the finger portions FA (3) and FB (4) are viewed in plan from the groove directions (6) and (8) is not particularly limited, and examples thereof include a triangle, a trapezoid, and the like.

[0021] The finger portions FA (3) and FB (4) can be formed by carving multiple parallel linear grooves into the end grain surface of the wood material A (1) or the flat grain surface or straight grain surface of the wood material B (2).Specific examples of the method include a method using a finger cutter, a method using a saw, laser processing, etc.

[0022] In this way, the wooden material A(1) on which the finger portion FA(3) is formed and the wooden material B(2) on which the finger portion FB(4) is formed are used to form the beam-column joint structure. The method for this is not particularly limited, but a preferred method is to apply adhesive to at least one of the finger portion FA(3) and the finger portion FB(4), and then harden the adhesive while pressing the finger portion FA(3) and the finger portion FB(4) in an engaged state. This method produces a beam-column joint structure in which the finger portion FA and the finger portion FB are joined at a finger joint via the adhesive. The method will be described in detail below.

[0023] The adhesive may be a general adhesive for wood materials, such as a resorcinol resin adhesive, a water-based polymer-isocyanate adhesive, a resorcinol-phenol resin adhesive, a melamine resin adhesive, a melamine urea resin adhesive, a modified vinyl acetate resin emulsion adhesive, an ethylene vinyl acetate resin emulsion adhesive, a urethane resin adhesive, or an epoxy resin adhesive.

[0024] After the adhesive is applied, the adhesive is cured while pressing the finger portion FA(3) and the finger portion FB(4) in a mated state. The pressing method may be any method that can hold the finger portion FA(3) and the finger portion FB(4) in a mated state with the fingers and the grooves in contact with each other. (i) A method of fastening wooden material A (1) and wooden material B (2) with a bolt while engaging finger portion FA (3) and finger portion FB (4), (ii) A method of pressing wooden material A (1) and wooden material B (2) with finger portion FA (3) and finger portion FB (4) engaged with each other using a press machine; etc.

[0025] Among them, method (i) is preferred. Method (i) is simple and easy, and can provide a beam-column joint structure in which the wooden material A (1) and the wooden material B (2) are fastened with a bolt, as described below. A specific method of fastening the bolts includes, for example, drilling an insertion hole (10) parallel to the grain direction (5) of the wooden material A (1) from a notch (9) provided in the flat grain surface or the straight grain surface of the wooden material A (1) to the surface of the wooden material B (2) opposite to the finger portion FB (4), inserting a bolt into the insertion hole (10), and fastening the wooden material A (1) and the wooden material B (2) with the bolt and a nut, as shown in FIG. 1.

[0026] The pressure applied when pressing the finger parts FA (3) and FB (4) together may be adjusted as appropriate depending on the type of wood material, etc. Typically, the pressure is 0.1 MPa or more, and may be 0.3 MPa or more, 0.5 MPa or more, or 0.7 MPa or more. On the other hand, if the pressure is too high, the entire wood material will be compressed, which may change the physical properties and texture of the wood, or the wood materials may sink into each other. Typically, the pressure is 3 MPa or less, and may be 2 MPa or less, or 1.5 MPa or less.

[0027] Also, the finger portion FA(3) and the finger portion FB(4) can be joined without using an adhesive as described below. After removing lignin from the surfaces of the finger portion FA(3) and the finger portion FB(4) using an alkaline aqueous solution containing an oxidizing agent, the finger portion FA(3) and the finger portion FB(4) are pressed together in a fitted state to contact each other in a wet state. Then, while still pressed, the wood material A(1) and the wood material B(2) are dried. This method can also form a finger joint in which the finger portion FA(3) and the finger portion FB(4) are firmly bonded together. As the oxidizing agent, an oxoacid salt of chlorine, such as hypochlorite, chlorite, or chlorate, is used. The content of the oxidizing agent in the aqueous solution is usually 1 to 15% by mass.

[0028] The pressing method is the same as the joining method using the adhesive described above. The temperature for drying the wood material A (1) and the wood material B (2) is usually 20 to 90°C, and the drying time is usually about one hour to one month.

[0029] From the viewpoint of improving the strength, it is preferable that the column-beam joint structure is formed by joining the wooden material A (1) and the wooden material B (2) with the finger joint and further fastening them with a fastener or fastening metal. As the fastener or fastening metal, those generally used for joining columns and beams are used. For example, the fastener includes a bolt, a nail, a screw, a screw bolt, etc., and the fastening metal includes a steel plate (splice plate), etc. Among them, it is preferable that the column-beam joint structure is formed by joining the wooden material A (1) and the wooden material B (2) with the finger joint and further fastening them with a bolt. As such a column-beam joint structure, there is a method of maintaining the bolt fastening performed to press the finger part FA (3) and the finger part FB (4) in the above-mentioned manufacturing method of the column-beam joint structure, etc.

[0030] In this way, a column-beam joint structure is manufactured in which the finger part FA (3) formed on the butt end surface of the wooden material A (1) and the finger part FB (4) formed on the cross-grain surface or straight grain surface of the wooden material B (2) are joined by a finger joint. One of the wooden material A (1) and the wooden material B (2) is a column, and the other is a beam. Whether the wooden material A (1) and the wooden material B (2) form a column or a beam during use can be determined taking into consideration the design of the entire building. Note that the finger parts FA and FB may be formed on the butt end surface and the cross-grain surface or straight grain surface of the column (or beam), and the above-mentioned finger joint may be formed with each wooden material. In this case, the column (or beam) becomes the wooden material A in relation to the wooden material joined to the butt end surface, and the column (or beam) becomes the wooden material B in relation to the wooden material joined to the cross-grain surface or straight grain surface.

[0031] A column-beam joint structure in which wood material A and wood material B are joined so that their grain directions are perpendicular to each other has high rigidity even without the aid of joints or metal joints. Therefore, this column-beam joint structure is used in a variety of buildings, including detached wooden houses, mid- to high-rise wooden houses, and non-residential buildings (especially large-scale non-residential buildings). EXAMPLES

[0032] The present invention will now be described in more detail with reference to examples.

[0033] Example 1 [Manufacturing of column-beam joint structures] Wood material A(1) and wood material B(2) were produced using laminated lumber E105-F300 of European red pine (Pinus sylvestris). FIG. 1 is a photograph showing the state when wood material A(1) and wood material B(2) are joined. FIG. 2 is a photograph showing an enlargement of finger portion FA(3) and finger portion FB(4) in FIG. 1. FIG. 3 is a schematic diagram of finger portion FA(3) and finger portion FB(4) in a fitted state, as viewed from the groove direction. FIG. 4 is a drawing of wood material A(1) and wood material B(2) (finger portion FA(3) and finger portion FB(4) are not shown). The laminated lumber is formed by stacking a plurality of laminas (sawn boards) so that the fiber direction is the longitudinal direction. The finger part FA (3) is formed on the entire butt surface (a rectangle with a long side of 240 mm and a short side of 120 mm) of the wood material A (1), and the groove direction (6) of the finger part FA (3) is perpendicular to the grain direction (5) of the wood material A (1). The rectangular finger part FB (4) with a long side of 380 mm and a short side of 120 mm is formed on the flat grain or straight grain surface of the wood material B (2), and the groove direction (8) of the finger part FB (4) is parallel to the grain direction (7) of the wood material B (2). The finger parts FA (3) and FB (4) were formed using a finger cutter. The pitch t1 (the distance between adjacent fingers) of the formed finger parts FA (3) and FB (4) was 3.8 mm, and the finger length t2 was 15 mm.

[0034] After a resorcinol resin adhesive is applied to the entire surfaces of the finger portions FA (3) and FB (4), the finger portions FA (3) and FB (4) are fitted together so that the fiber directions (5), (7) of the wooden material A (1) and the wooden material B (2) are perpendicular to each other. Then, the wooden material A (1) and the wooden material B (2) are fastened together with the finger portions FA (3) and FB (4) fitted together by means of a bolt and a nut inserted into an insertion hole (10) that is drilled from a notch (9) on the flat grain or straight grain surface of the wooden material A (1) to the surface of the wooden material B (2) opposite the finger portion FB (4) and that is parallel to the fiber direction (5) of the wooden material A (1). The joint between finger part FA (3) and finger part FB (4) was left to cure at room temperature for several days to harden the adhesive, thereby producing a beam-column joint structure (test specimen) in which wooden material A (1) and wooden material B (2) were joined by a finger joint. Three such test specimens were produced and subjected to the following moment load test.

[0035] [Moment load test] The test specimen was set on a horizontal loading frame as shown in Figure 5, and six displacement gauges were attached as shown in Figure 6. Displacement gauge 1 was attached to the loading point and measured the horizontal displacement when loaded. Displacement gauge 2 measured the horizontal displacement of wooden material B (2) (beam). Displacement gauges 3 and 4 measured the floating of wooden material A (1) (column) from wooden material B (2) (beam). Displacement gauges 5 and 6 measured the floating of wooden material B (2) (beam) from the installation surface.

[0036] (Calculating the rotation angle) The rotation angle of wood material A (1) (pillar material) when force was applied was calculated from the values ​​measured by the six displacement gauges above. The distance between displacement gauges 1 and 2 was l1, the displacement of displacement gauge 1 was d1, the displacement of displacement gauge 2 was d2, the distance between displacement gauges 3 and 4 was l2, the displacement of displacement gauge 3 was d3, and the displacement of displacement gauge 4 was d4. The apparent rotation angle and true rotation angle were calculated as follows. Apparent rotation angle: θ a =(d1-d2) / l1 True rotation angle: θ r =(d4-d3) / l2

[0037] (Force Schedule) The moment load test was carried out by alternating push and pull on the apparent rotation angle of wood material A (1) (pillar material) to 7 stages: 1 / 450 (rad), 1 / 300 (rad), 1 / 200 (rad), 1 / 150 (rad), 1 / 100 (rad), 1 / 75 (rad), and 1 / 50 (rad). At each stage, the material was pushed and pulled alternately, with positive being pushed and negative being pulled, and the material was subjected to alternating positive and negative loads three times each. If the specimen had not yet broken after three loads of 1 / 50 (rad) had been completed, the load was continued in one direction until it broke.

[0038] As described above, when a moment load test was actually performed on the specimen, transverse tensile fracture was observed at the bottom of the finger joint, as shown in Fig. 7. Therefore, the error in the rotation angle due to the transverse tensile fracture was corrected as follows:

[0039] (True rotation angle correction) Because an error occurred between the actual rotation angle and the calculated rotation angle due to the effect of transverse tensile fracture, a correction calculation was made taking into account the uplift caused by the transverse tensile fracture. Assuming that a split had occurred as shown in Figure 8, the displacement d3' corrected for the uplift of the lower part of displacement gauge 3 and the displacement d4' corrected for the uplift of the lower part of displacement gauge 4 were calculated using the following formula. d3'=d3-(d5×l3) / l5) d4'=d4-(d6×l4) / l6)

[0040] In addition, the corrected displacements d3' and d4' are used to calculate the true rotation angle θ r ' was calculated by the following formula. θ r '=(d4'-d3') / l2

[0041] Figure 9 shows an example of a "true rotation angle-moment diagram" obtained from a moment loading test on a specimen. Figure 12 shows the initial rotation stiffness, Figure 13 shows the maximum moment, and Figure 14 shows the structural characteristic coefficient. The structural characteristic coefficient was obtained by drawing a skeleton curve using Pick Point (https: / / www.ffpri.affrc.go.jp / labs / etj / karube / PickPoint / index-j.html) from the moment and rotation angle obtained in the experiment, and transforming it into a bi-linear type. Pick Point is a program that can process a series of operations to transform a load deformation curve into a bi-linear type. Structural characteristic coefficient D s P is the maximum load max When this is done, it becomes 0.8P. max The rotation angle at time is δ v , the rotation angle at the ultimate strength is δ u It can be calculated by the following formula. The characteristic coefficient can be used to evaluate toughness. The smaller the structural characteristic coefficient, the greater the toughness. μ=δ u / δ v D s =1 / (2μ-1) 1 / 2

[0042] Example 2 After the adhesive was cured, the bolts and nuts that had been fastening the wooden material A (1) and the wooden material B (2) were removed, and the column-beam joint structure (specimen) was manufactured and evaluated in the same manner as in Example 1. One specimen was manufactured and evaluated. The results are shown in Figures 10, 12 to 14.

[0043] Comparative Example 1 A beam-column joint structure (specimen) was manufactured and evaluated in the same manner as in Example 1, except that the adhesive was not applied and cured. Two specimens were manufactured and evaluated. The results are shown in Figures 11 to 14. Shear fracture occurred at the bolt position of the specimen due to the load applied during the moment load test. Figure 15 shows a photograph of the specimen in which shear fracture occurred at the bolt position.

[0044] As a result of carrying out a moment load test on the beam-column joint structure (test specimen), in the beam-column joint structure (test specimen) of Example 1, in which the finger parts FA(3) and FB(4) were bonded and bolted, horizontal tensile failure (Fig. 7) occurred at the lower part of the finger part FB(4) of the wooden material B(2) and shear failure occurred at the bolt position, but no failure occurred at the joint between the finger parts FA(3) and FB(4). In addition, in the beam-column joint structure (test specimen) of Example 2, in which only the finger parts FA(3) and FB(4) were bonded, horizontal tensile failure occurred at the lower part of the finger part FB(4), but no failure occurred at the joint between the finger parts FA(3) and FB(4). These results show that by forming the specified finger parts FA (3) and FB (4) on the end grain surface of wood material A (1) and the flat or straight grain surface of wood material B (2) and joining them with a finger joint, wood materials with perpendicular fiber directions can be joined with high adhesive strength. In the beam-column joint structure (test specimen) of Example 2, lateral tensile failure occurred at the bottom of finger part FB (4), but this is thought to be due to the fact that the top of wood material B (2) was cut away midway to allow for the insertion of a bolt for fixing to the horizontal load frame (see Figures 4 and 5), and it is thought that the strength would have been even higher if there had been no such cutout. 12 shows that the column-beam joint structures (test specimens) of Examples 1 and 2 in which the finger portions FA(3) and FB(4) were bonded had higher initial rotational rigidity than the column-beam joint structure (test specimen) of Comparative Example 1 in which only bolt fastening was performed, and it is clear that the finger joint formed by fitting and bonding the finger portions FA(3) and FB(4) is effective in improving rotational rigidity. From Figures 12 to 14, it can be seen that by combining the finger joint formed by bonding the finger portions FA(3) and FB(4) with bolt fastening (Example 1), a column-beam joint structure excellent in resistance strength and toughness as well as rotational rigidity can be obtained. [Explanation of symbols]

[0045] 1 Wood material A 2 Wood material B 3 Finger section FA 4 Finger part FB 5, 7 Fiber direction 6, 8 groove direction 9 Cutout 10 Insertion hole 21 Base material 22 Joint 23 Finger section t1 pitch t2 finger length

Claims

1. A column-beam joint structure in which wood material A and wood material B are joined so that their fiber directions are perpendicular to each other, A finger portion FA formed on the end surface of the wood material A and a finger portion FB formed on the cross grain surface or the straight grain surface of the wood material B are joined by a finger joint. The fiber direction of the wood material A and the groove direction of the finger portion FA are perpendicular to each other. The fiber direction of the wood material B is parallel to the groove direction of the finger portion FB. A column-beam joint structure in which one of the wooden materials A and B is a column and the other is a beam.

2. The column-beam joint structure according to claim 1 , wherein the finger portion FA and the finger portion FB are joined by a finger joint via an adhesive.

3. 3. The column-beam joint structure according to claim 1 or 2, further comprising: the wooden material A and the wooden material B fastened together by a bolt.

4. 3. The manufacturing method of a column-beam joint structure according to claim 2, further comprising applying an adhesive to at least one of the finger portion FA and the finger portion FB, and then hardening the adhesive while pressing the finger portion FA and the finger portion FB in an engaged state.

5. 4. The manufacturing method of a beam-column joint structure according to claim 3, wherein an adhesive is applied to at least one of the finger portion FA and the finger portion FB, and then the adhesive is hardened while being pressed by fastening a bolt while the finger portion FA and the finger portion FB are engaged with each other.

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