JP2023072380A - Joint structure between rectangular timbers - Google Patents

Abstract

To provide a joint structure between rectangular timbers of a wooden building capable of withstanding a load in a drawing direction by a simple process.SOLUTION: Provided is a joining structure between rectangular timbers for joining one rectangular timber 3 and the other rectangular timber 2 orthogonal to the longitudinal end of the rectangular timber in a wooden building. A pair of screws 7 and 9 are driven obliquely from both sides of one rectangular timber 3. The pair of screws 7 and 9 pass through one rectangular timber 3 and have their tips inserted into the other rectangular timber 3. The pair of screws 7 and 9 intersect with the other within the other rectangular timber 2 .SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a joining structure for joining square timbers of a wooden building.

In wooden architecture, square timber columns and horizontal timbers are joined together. In particular, the horizontal members and columns that make up beams or girders, and the horizontal members that make up beams and girders, are joined orthogonally to each other to form multiple rectangular shapes, forming a three-dimensional building framework. are doing. By the way, in Japan, which has more typhoons and earthquakes than other countries, the shaking caused by strong winds and earthquakes often affects the building frame. lead to damage.

Damage to the building frame includes, for example, detachment of jointed rectangular timbers. As an example of the cause of detachment, if we take the joints between columns and horizontal members as an example, when shaking due to strong winds or earthquakes occurs, depending on the position where the column is erected and the load of the building on the column, the column An excessive load is applied in the pull-out direction, that is, in the vertical separation direction between the column and the horizontal member. For this reason, it is obligatory to perform structural calculations that meet the standards for withstanding the load applied to the pillars and horizontal members of a wooden building in the pull-out direction (Ministry of Construction Notification No. 1460).

Regarding the joints between columns and horizontal members, the pull-out load applied to the columns differs depending on the position of the joints in the building frame and the presence or absence of load-bearing walls attached to the columns. Columns erected at corners are likely to be subjected to a large load in the pull-out direction when shaking occurs. Therefore, it is reinforced using a hold-down metal fitting.

A hold-down metal fitting connects a fixing metal fitting provided on the side surface of a column to an anchor bolt protruding through a horizontal member from foundation concrete (see, for example, Patent Document 1). In this way, the hold-down metal fitting has a structure that binds the pillar itself to the foundation concrete via the hold-down metal fitting. Even if a load of 1000 is applied, the joint state between the column and the horizontal member can be maintained.

JP 2010-19000 (pages 3-6, Figure 3)

As mentioned above, especially for pillars set up at the corners of the foundation of a building, a large load is applied in the pull-out direction when shaking occurs. In some cases, pillars erected near the center of the building are likely to rise relatively large, and it is necessary to reinforce joints that satisfy the load in the pull-out direction applied to the pillars. . In such cases, hold-down metal fittings can be used as general reinforcing metal fittings for the joints between the relevant columns and horizontal members. There is a problem that the joining process becomes very complicated because it requires a process of joining the fixing metal fittings arranged on the side surface of the column to the anchor bolt protruding through the horizontal member.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a joining structure for square timbers of a wooden building that can withstand a load in the pull-out direction through a simple process.

In order to solve the above-mentioned problems, the joining structure of rectangular timbers according to the present invention includes:
A joining structure between square timbers for joining one square timber and the other square timber perpendicular to the longitudinal end of the square timber in a wooden building,
A pair of screws are driven obliquely from both sides of the one square timber. It is characterized by intersecting within the other square bar.
According to this feature, a pair of screws driven obliquely from both side surfaces of one square timber into the other square timber is relatively displaced in the separation direction between the one square timber and the other square timber, and in a direction orthogonal to the separation direction. A pair of screws driven diagonally from both sides of one square timber intersect within the other square timber, so that the crossed The density of wood fibers between the front and back of the screws is increased, and the pull-out strength of these screws is improved, so the relative displacement of one square timber and the other square timber in the detachment direction can be suppressed, and joining can be performed in a simple process. It can withstand the load in the pull-out direction applied between squared timbers.

The tenon formed at the longitudinal end of one of the square timbers is press-fitted into a mortise hole formed in the other square timber, and the pair of screws are driven obliquely across the tenon. and
According to this feature, a pair of diagonally hammered screws are placed on both sides of the tenon, so when the screws enter, the wood fibers in the front and back of the mortise hole are compressed and the density is increased, and the tenon is removed from the mortise hole. It becomes difficult to come off, that is, resistance to relative displacement in the separation direction between one square timber and the other square timber and relative displacement in the direction perpendicular to the separation direction is improved.

A corner fitting having at least two pieces orthogonal to each other by bending the metal plate is disposed on at least one side surface of the one square timber, and one of the pieces of the corner fitting is a side surface of the one square timber. and the other piece is screw-fixed in a state of being in contact with the surface of the other square timber perpendicular to the side surface of the one square timber,
The pair of screws are characterized in that they are obliquely driven with the corner metal fittings sandwiched therebetween.
According to this feature, since the pair of obliquely driven screws are arranged in front and behind the corner metal fitting, a large resistance against relative displacement in the separation direction between one square timber and the other square timber can be obtained. This reduces the distortion of the corner fitting that is fixed between one square timber and the other square timber and can join them, making it difficult to reach the yield point. With only a simple process using , the joint structure as a whole can withstand a relatively large load in the pulling direction.

On each side surface of the one square timber, the distance between the screws driven in with the corner metal fitting therebetween is arranged at equal intervals on both side surfaces of the one square timber.
According to this feature, the distance between the pair of obliquely hammered screws is equal to each other across the corner metal fitting, and the density of the wood fibers increased before and after the pair of screws intersect becomes uniform, which in turn results in uniformity. The pull-out resistance of the screws can be made uniform by sandwiching the corner metal fittings, and the resistance to the relative displacement in the separation direction between one square timber and the other square timber and in the direction orthogonal to the separation direction is eliminated. , can effectively prevent local breakdown in the junction structure.

The screw is driven in at an angle of 60° with respect to the surface of the other square timber perpendicular to the side surface of the one square timber.
According to this feature, when the screws are driven with an inclination of 60°, the left and right external angles in the horizontal direction sandwiching the intersection of the pair of screws are also 60°. Good balance of resistance against relative displacement in the direction of rotation. In addition, after ensuring the balance of this resistance force, they are crossed at a deep position in the other square timber, and a load in the pulling direction when shaking occurs is applied at a deep position in this other square timber, separating them. A relative displacement in the direction can be effectively prevented.

FIG. 2 is a perspective view showing a joint structure between a pillar, which is a square timber, and a horizontal member in Example 1 of the present invention. It is a partial expansion perspective view which shows a pillar and a horizontal member. (a) is a side view showing a corner fitting, and (b) is a front view. (a) is a schematic diagram showing a mortise assembling process, (b) is a schematic diagram showing a corner fitting mounting process, and (c) and (d) are schematic diagrams showing a screw driving process. (a) is a front view of a pillar and a horizontal member in which a joint structure between the pillar and the horizontal member is implemented, and (b) is a side view thereof. (a) shows the test results of a tensile test of the joint structure that was only performed in the tenon assembling process and the screw driving process, and (b) shows the tensile test results of the joint structure between the column and the horizontal member of this example. It shows the test results of the test. FIG. 10 is a partially enlarged side view and a partially enlarged schematic diagram of the vicinity of the region C; FIG. 11 is a partially enlarged front view of the vicinity of area C; FIG. 11 is a perspective view showing a joint structure between horizontal members which are rectangular timbers in Example 2; It is a perspective view which shows the joint structure of the column and horizontal member which are square lumbers in a modification.

A mode for carrying out the joining structure of rectangular timbers according to the present invention will be described below based on an embodiment.

A joint structure of rectangular timbers according to Example 1 will be described with reference to FIGS. 1 to 8. FIG. Hereinafter, the lower left side of the paper surface of FIG. described as a direction.

As shown in FIG. 1A, the joining structure 1 between square timbers described in this embodiment is a joining structure between a column 3 and a horizontal member 2, which are square timbers. The joint structure 1 in the present embodiment assumes the case of joining a pillar erected on the center side of the building from a pillar erected at a corner of a building foundation and a horizontal member. It has a tensile strength of up to 16.8 kN. Although not shown here, it is assumed that the conventional hold-down fittings are used for the pillars erected at the corners of the foundation of the building. Furthermore, in the present embodiment, the connection between the horizontal member 2, which is the crosspiece at the bottom of the building, and the column base of the column 3 will be taken as an example, and only the main part will be enlarged for explanation. It goes without saying that it can also be used in other places where bearing strength is required, such as the capital of a column.

As shown in FIG. 2, the horizontal member 2 is, for example, a rectangular member with a vertical and horizontal cross-sectional dimension of 105 mm square, and is placed on the upper surface of the foundation (not shown). On the upper surface 2a of the horizontal member 2, a mortise 4 is formed as a substantially rectangular parallelepiped concave portion with a bottom. The mortise 4 is composed of a short right side 4a, a left side 4c, a long front 4b, a rear 4d, and a bottom 4e. is also made slightly larger. The mortise 4 may be formed as a recessed groove or a through hole, and the horizontal member 2 may be made of, for example, cypress, pine, or cedar.

The column 3 is, for example, a square timber with vertical and horizontal cross-sectional dimensions of 105 mm square. is formed. The column 3 of this embodiment is mortise-jointed with the above-described horizontal member 2 on the column base side, and tenon-joined with a horizontal member (not shown) that is horizontally spanned above the building skeleton (not shown) on the column head side. The lower surface 3a of the column 3 is formed with a tenon 5 mainly composed of a short right side 5a, a left side 5c, a long front surface 5b, a rear surface 5d, and a bottom surface 5e. The front, rear, left, and right dimensions of the tenon 5 are slightly larger than the front, rear, left, and right dimensions of the mortise hole 4 of the horizontal member 2 described above. As the material of the pillars 3, for example, cedar, cypress, or ebony can be used.

The tenon 5 of the post 3 is press-fitted into the mortise 4 of the beam 2 until the bottom surface 3a of the post 3 contacts the top surface 2a of the beam 2, and the left side 3c of the post 3 and the top surface 2a of the beam 2 are pressed together. and a corner R that is perpendicular to the right side surface 3b of the pillar 3 and the upper surface 2a of the horizontal member 2 (so-called mortise joint). By mortising the horizontal member 2 and the column 3 in this way, the relative displacement of the horizontal member 2 and the column 3 in the torsional direction and in the vertical direction is suppressed to some extent. I can say.

As shown in FIGS. 3(a) and 3(b), the corner metal fitting 6 is a substantially L-shaped metal fitting in a side view, which is made by hot-dip galvanizing a high-strength steel plate having a thickness of about 2.3 mm. The corner metal fitting 6 is formed by bending a steel plate so as to mainly include a base portion 60, a raised portion 61, and an inclined portion 62 having approximately the same thickness. A plurality of through holes 6A are formed in the base portion 60, and a plurality of through holes 6B are formed in the rising portion 61. As shown in FIG.

The base portion 60 and the rising portion 61 are integrally connected by an inclined portion 62 . The inclined portion 62 is continuous with the left end portion of the horizontally extending base portion 60 and the lower end portion of the rising portion 61 extending in a direction perpendicular to the base portion 60, and is inclined at about 60 degrees with respect to the base portion 60. there is Also, as shown in FIG. 3(a), the widthwise dimension S1 of the base portion 60 and the inclined portion 62 of the corner fitting 6 is combined, and the longitudinal dimension S2 of the raised portion 61 and the inclined portion 62 is combined. ratio is about 1:3.

In this embodiment, the corner fitting 6 is installed at the corner R formed by the right side surface 3b of the pillar 3 and the upper surface 2a of the horizontal member 2. As shown in FIG. When installing the corner fitting 6 at the corner R, the raised portion 61 is brought into contact with the right side surface 3b of the pillar 3, and screwed to the pillar 3 through the through holes 6B using a plurality of screws 6a. is placed on the upper surface 2a of the horizontal member 2 and screwed to the horizontal member 2 through the through holes 6A using a plurality of screws 6a.

Returning to FIG. 1, the screws 7 to 10 are so-called wood screws made of carbon steel and mainly composed of a head portion B1 and a trunk portion B2. The directional dimension is about 4 mm and the axial dimension is about 120 mm.

After attaching the corner metal fitting 6 to the corner R, the screws 7 to 10 are directed from the corners L and R of the pillar 3 into the horizontal member 2 using a screwing jig 20 (see FIG. 4(c)). is driven. The screw driving jig 20 is made of a metal material and mainly composed of a base 25 and two bottomless cylindrical bodies 23 and 24 . The base 25 is composed of a base portion 21 which is flat and flat, and an inclined portion 22 which is continuously bent at an acute angle from the base portion 21 and rises obliquely upward. 24 is attached. Further, ribs V extending downward continuously from the base portion 21 are formed at one end portions on the left and right sides of the base portion 21 . The rib V is formed substantially perpendicular to the base portion 21 .

The cylindrical bodies 23 and 24 are attached with a predetermined distance from each other in the width direction of the inclined portion 22 . The predetermined interval is larger than the dimension of the tenon 5 and the mortise 4 in the front-rear direction and the dimension H of the corner fitting 6 in the front-rear direction (see FIG. 3(b)), and the dimension of the horizontal member 2 in the front-rear direction. refers to intervals smaller than

Next, the procedure for implementing the joint structure 1 between the column and the horizontal member will be described with reference to FIGS. 4(a) to 4(d) and FIGS. First, as shown in FIG. 4(a), the tenon 5 formed on the lower surface 3a of the column 3 is aligned with the mortise hole 4 formed on the upper surface 2a of the horizontal member 2, press-fitted, and the corner portion L and R are formed (tenon assembling process).

Next, as shown in FIG. 4(b), the corner fitting 6 is attached to the corner portion R formed through the mortise and tenon assembling process. When attaching the corner fitting 6, the raised portion 61 is brought into contact with the right side surface of the pillar 3, and screwed to the pillar 3 through the through holes 6B using a plurality of screws 6a. It can be fixed by placing it on the upper surface 2a and screwing it to the horizontal member 2 through the through holes 6A using a plurality of screws 6a (corner fitting mounting step).

Next, as shown in FIG. 4(c), the base portion 21 of the screwing jig 20 is placed on the upper surface 2a of the horizontal member 2 on the near side from the corner R, and the rib V is placed on the horizontal member 2. The cylindrical bodies 23 and 24 are brought into contact with the side surface 2b, and the tip portions of the cylindrical bodies 23 and 24 are moved to a position where they contact the column 3 and are positioned. At this time, since the front-rear dimension of the base portion 21 is shorter than the upper surface 2a of the horizontal member 2, the cylindrical bodies 23 and 24 are arranged to be biased toward the side surface 2b from the central position in the width direction of the base portion 21. As shown in FIG.

In this state, the screws 7 and 8 are inserted from the tip side through the upper openings of the cylindrical bodies 23 and 24, respectively, and driven in using an electric screwdriver. The screws 7 and 8 driven by the screw driving jig 20 are guided by the cylindrical bodies 23 and 24 and driven linearly at equal intervals with an inclination of about 60 degrees with respect to the horizontal member 2 . The screws 7 and 8 driven until the head B1 abuts on the pillar 3 have their tips passed through the right side surface of the pillar 3, the bottom surface, the upper surface of the horizontal member 2, and the axial center of the horizontal member 2. It reaches up to the neighborhood. In addition, the cylindrical bodies 23 and 24 of the screw driving jig 20 are arranged at a predetermined interval, so that they enter the horizontal member 2 while avoiding the corner fitting 6, the tenon 5, and the tenon hole 4. It's becoming

As shown in FIG. 4(d), screws 9 and 10 are similarly driven obliquely downward from the corner L using a screw driving jig 20. As shown in FIG. At this time, the rib V is brought into contact with the side surface 2 c of the horizontal member 2 . Since the cylindrical bodies 23 and 24 are arranged so as to deviate from the central position in the width direction of the base portion 21 toward the side surface 2b, the screws 9 and 10 are positioned within the horizontal member 2 so that the screws 7 and 8 driven from the corner portion R are located at the side surface 2b. (See FIG. 5(b)).

Next, the test results of the tensile test will be described with reference to FIGS. 6(a) and 6(b). In the tensile test, cedar was used for the columns and cypress was used for the horizontal members. Then, we measured the distance that the lower surface of the column was separated from the upper surface of the horizontal member, and also observed which member had what kind of failure that caused yielding.

In the test results of FIGS. 6(a) and 6(b), the amount of displacement indicates the distance that the lower surface of the column separates from the upper surface of the horizontal member when it yields. The load Py (kN) and displacement δy (mm) in the table each show the value at yield, and among the values calculated by multiplying the average value of the yield strength (Py) or 2/3Pmax by the respective variation coefficient is calculated as the short-term standard tensile strength. From this short-term reference tensile strength, it is possible to determine the load that the joint structure as a whole can maintain with respect to the load applied in the vertical separation direction.

FIG. 6(a) shows the results of a tensile test performed on a joint structure between a column and a horizontal member, which is composed only of tenon joints and oblique screwing structures. According to this, the amount of displacement at yield was as small as about 0.3 mm at any load. According to the state of destruction, the pillar split due to the head of the screw getting into the pillar. From this, the load in the pull-out direction applied to the pillar acts to pull the head of the pair of screws toward the center of the pillar, and the wood fibers of the pillar are formed at the inner corners where the pair of screws intersect. It was found that the screws are pinched and withstand the load tenaciously applied between the columns and horizontal members, suppressing displacement. The short-term standard tensile strength of this joint structure was 7.1 kN.

By the way, in a tensile test (not shown), the short-term standard tensile strength of the corner fitting alone is about 10.0 kN. In addition, the displacement amount at the time of yielding of the corner fitting alone is 4.1 mm on average. In this way, the corner metal fitting is configured to prevent the pull-out of the column and the horizontal member against the load by distorting in the vertical direction against the load in the pull-out direction. In addition, the displacement in the pull-out direction between the column and the horizontal member is large.

FIG. 6(b) shows the results of a tensile test of a joint structure of a column having a mortise joint, a corner metal fitting, an oblique screwing structure, and a horizontal member, as in this embodiment. According to this, the short-term standard tensile strength is 16.8 kN, which is greatly improved compared to the corner fitting alone. Moreover, the displacement amount at the time of yielding is about 0.8 mm on average, and the vertical displacement is greatly reduced compared to the single corner fitting. Based on this, the reason why the short-term standard tensile strength is improved is that the load applied to the corner metal fitting is reduced by suppressing the vertical displacement of the diagonally hammered screw, which makes it difficult for the corner metal fitting to reach the yield point. In addition, the slight distortion of the corner metal fittings made it difficult for the head of the screw to be pulled into the center of the pillar, which is thought to have prevented the pillar from splitting.

From the above test results, it can be seen that the screws 7 to 10, which are driven diagonally from the right side 3b and left side 3c of the column 3 to the inside of the column 3 and the horizontal member 2, are aligned in the vertical separation direction between the column 3 and the horizontal member 2. It is possible to exert a force that resists the relative displacement to the left and right, respectively, and the relative displacement of the column 3 and the horizontal member 2 in the detachment direction is suppressed. I found out. For this reason, it is suitable for places where a large load does not act in the pull-out direction compared to the joints between the columns 3 and the horizontal members 2, such as the joints between the beams and girders, which are horizontal members. In addition, by adopting the configuration in which the screws 7 and 9 or the screws 8 and 10 are slanted, the load in the pull-out direction can be sufficiently withstood even if corner metal fittings are omitted.

In addition, by screwing the corner fittings 6 to either side surface of the pillar 3 and the upper surface 2a or the lower surface of the horizontal member 2, respectively, the load in the pulling direction of the pillar 3 and the horizontal member 2 due to the corner fittings 6 can be reduced. In addition, the distortion of the corner metal fitting 6 is alleviated by the effect of suppressing the displacement in the relative detachment direction exerted by the obliquely hammered screws 7 to 10, making it difficult for the corner metal fitting 6 to reach the yield point. The joint structure as a whole can withstand a relatively large load in the pull-out direction only by a simple process using oblique screw driving and corner metal fittings of a simple structure.

Although not shown here, according to the results of a tensile test of the joint structure of the pillar and horizontal members, in which corner metal fittings are attached to the left and right sides of the pillar in addition to the mortise and mortise joints and diagonal screw driving, short-term The standard tensile strength increased slightly to 17.4 kN. In this way, the corner fittings may be attached to both the left and right sides of the pillar, but since the difference from the case where they are attached to either the left or right side is 0.6 kN, the tension required for structural calculations is The number of corner metal fittings can be appropriately selected in view of the yield strength, the material price of the corner metal fitting main body, and the installation cost of the corner metal fittings.

Further, since the screws 7 to 10 are wood screws, they have the effect of increasing the density of the wood fibers in the horizontal member 2 by being obliquely driven into the horizontal member 2 . Next, with reference to FIG. 7, an aspect near the mortise hole 4 of the horizontal member 2 to which the screws 7 and 9 on the near side are obliquely driven will be described.

Tenon 5 formed on the lower surface 3a of the pillar 3 is aligned with the mortise 4 formed on the upper surface 2a of the horizontal member 2 and press-fitted in the mortise assembling process. The wood fibers are compressed and dense.

During the screw driving process, the wood fibers of the horizontal member 2 are pushed aside and entered, and in the region C where the screws 7 and 9 intersect in the horizontal member 2 in the front-rear direction, the wood fibers are compressed and become dense. , and the pull-out strength of the screws 7 and 9 is improved.

In addition, due to the entry of the screw 7 and the press-fitting of the tenon 5, the wood fibers are also compressed and dense in the area D between the front surface 4b of the screw 7 and the front surface 4b of the mortise hole 4, and the pull-out resistance of the screw 7 is increased. Furthermore, the pull-out resistance of the tenon set by the tenon 5 and the tenon hole 4 is improved.

Next, with reference to FIG. 8, a mode near the area C will be described. Here, the screws 7 and 9 forming the region C on the front side of the horizontal member 2 will be described. As shown in FIG. 8, during the screw driving process, the screws 7 and 9 are driven at an angle of 60 degrees from the upper surface of the horizontal member 2, so that the upper surface of the horizontal member 2 and the screws 7 and 9 form a 60-degree angle. A substantially equilateral triangle is formed. In other words, the left and right outer angles in the horizontal direction sandwiching the intersection of the pair of screws 7 and 9 are also 60°, and the resistance force against the relative displacement in the vertical separation direction and the relative displacement in the horizontal direction. good balance. In addition, after securing the balance of this resistance force, a pair of screws 7 and 9 are crossed at a deep position in the horizontal member 2, and the load in the pull-out direction when shaking occurs is applied to the horizontal member 2. , and can effectively prevent relative displacement in the vertical separation direction.

Further, when the vertical and horizontal cross-sectional dimensions of the column 3 and the horizontal member 2 are 105 mm square, the axial dimension of the body portion B2 of the screws 7 to 10 is about 120 mm as described above, and the vertical and horizontal dimensions of the column and the horizontal member are approximately 120 mm. The axial dimension of the screw body B2 is 1.14 times the cross-sectional dimension of . It can be crossed by entering 40%. In this way, when about 20% to 40% of the tip of the body portion B2 of the screw enters into the horizontal member 2, it is difficult for the column to split due to the load in the pulling direction, and the screw to the horizontal member does not easily break. It can be said that it is the best because it can sufficiently secure the bite of the.

In addition, the corner fitting 6 has an inclined portion 62 between the base portion 60 and the raised portion 61. Since the inclined portion 62 is spaced from the corner portion R, the column 3 and the horizontal member 2 are Mutual breakage due to contact with corners R where stress concentrates can be prevented during vertical displacement accompanied by relative rotation. In particular, by preventing direct damage due to contact between the right side surface 3b of the column 3 and the upper surface 2a of the horizontal member 2, which constitutes the corner R, the pull-out strength of the screws 7-10 can be maintained. Further, when the column 3 and the horizontal member 2 are displaced in the vertical direction with relative rotation, the internal angle of the bent portion which is the boundary between the inclined portion 62 and the rising portion 61 The internal angle of the bent portion, which is the boundary between and, is always an obtuse angle, so metal fatigue due to strain is small and durability is excellent.

In addition, if a joint structure that uses all of the mortise 4 of the horizontal member 2 and the tenon 5 of the column 3, the fixing of the corner metal fitting 6, and the diagonal driving of the screws 7 to 10 is adopted, the short-term standard Since it has a tensile strength of about 16.8 kN, it can be applied to columns that require a tensile strength of up to about 16.8 kN in terms of building structural calculations. For this reason, as described above, it is applicable mainly to columns and horizontal members erected on the central side of the building rather than columns erected at the corners of the base portion of the building. Therefore, in the past, the joint between the pillar and the horizontal member, which are mainly installed in the corner of the building foundation, and the pillar and the horizontal member, which are erected on the center side of the building from the pillar in the corner. A total of 19 hold-down metal fittings with a short-term standard tensile strength of about 28 kN were used for joining, but this By applying the joint structure 1 of the invention between a column and a horizontal member, the number of hold-down metal fittings used per house could be reduced by 14.

Next, a joint structure of rectangular timbers according to Example 2 will be described with reference to FIG. 9 . The same components as those shown in the above embodiments are denoted by the same reference numerals, and overlapping descriptions are omitted.

The joint structure 31 is a joint structure between a beam 33 and a girder 32, which are rectangular beams and horizontal members. In this embodiment, the dovetail hook 34 and the screws 7 to 10 are diagonally driven from both sides of the beam 33 . Although the details of the dovetail hook 34 are not shown here, a notch and a dovetail hole are provided on the side surface of the girder 32, and a dovetail tenon is formed at the longitudinal end of the beam 33 that engages at right angles, and these are fitted. It is a thing.

The screws 7, 9 and the screws 8, 10 are spaced apart above and below the beam 33 and form pairs. According to this, the pull-out resistance of the screws 7 to 10 whose tips are slanted so as to intersect in the girder 32 and the pull-out resistance of the large dovetail hook 34 work together, so that each joint is compared to a single unit. The structure as a whole can withstand relatively large pull-out loads.

Although the embodiments and modifications of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention may be modified or added without departing from the gist of the present invention. Included in the invention.

Further, in the above-described embodiment, an example in which a screw driving jig is used during the screw driving process has been described. However, the present invention is not limited to this. It is also possible to obliquely strike using the like.

In addition, in the first embodiment, an example of attaching the corner fitting to the corner R during the step of attaching the corner fitting has been described, but the present invention is not limited to this. Corner fittings may be attached to L and R, respectively.

In the first embodiment, the vertical and horizontal cross-sectional dimensions of the column 3 and the horizontal member 2 are 105 mm square, the radial dimension of the body of the screws 7 to 10 is about 4 mm, and the axial dimension is about 120 mm. explained that it is desirable to This is because about 20% to 40% of the tip of the body portion of the screw enters into the horizontal member 2 to cross it. In order to satisfy this condition, the axial dimension of the screw should be about 1.14 to 1.2 times the vertical and horizontal cross-sectional dimensions of the column and the horizontal member. The dimensions are not limited to numerical values, and can be changed as appropriate according to the vertical and horizontal cross-sectional dimensions of the pillars and the horizontal members.

In addition, floor plywood may be directly nailed to the upper surface 2a of the horizontal member 2 in order to make the floor rigid with strong resistance to horizontal loads. are omitted. When using floor plywood, the step of attaching corner brackets is performed after the step of attaching floor plywood after the step of mortise assembling. At that time, the joint structure of the present invention can be implemented by attaching the corner metal fittings to the side surface of the column and the floor plywood and performing the screw driving process.

Moreover, the joint structure is not limited to the structure used at the joint between the horizontal member 2, which is the crosspiece at the bottom of the building, and the column base of the column 3 as in the first embodiment. As in the joint structure 41 of the example, it may be used when joining the longitudinal ends of the horizontal members 42 to the side surfaces of the pillars 43 . In addition, in this figure, the tilted large insertion 44 is also used, and the pull-out strength of the screws 7 to 10 whose tips are slanted so that they intersect in the column 3 and the relative strength exerted by the slanted screws 7 to 10 The relaxation of the distortion of the corner fitting 6 due to the effect of suppressing the displacement in the detachment direction and the pull-out resistance due to the tilted large insertion 44 work together, so that the joint structure as a whole has a relatively large load in the pull-out direction compared to the single unit. can withstand.

1 Joint structure 2 Horizontal member 3 Column 4 Mortise hole 5 Tenon 6 Corner metal fittings 7 to 10 Screw 20 Screw driving jig 23, 24 Cylindrical body 31 Joint structure 34 Large dovetail hook 41 Joint structure 44 Tilt large insert 60 Base 61 Rising portion C Area L Corner R Corner M Area

Claims (5)

A joining structure between square timbers for joining one square timber and the other square timber perpendicular to the longitudinal end of the square timber in a wooden building,
A pair of screws are driven obliquely from both sides of the one square timber. A joint structure of square timbers, characterized in that the square timbers intersect within the other square timber. A tenon formed at the longitudinal end of one of the square timbers is press-fitted into a mortise hole formed in the other square timber, and the pair of screws are driven obliquely across the tenon. The joining structure of rectangular timbers according to claim 1. A corner fitting having at least two pieces orthogonal to each other by bending the metal plate is disposed on at least one side surface of the one square timber, and one of the pieces of the corner fitting is a side surface of the one square timber. and the other piece is screw-fixed in a state of being in contact with the surface of the other square timber perpendicular to the side surface of the one square timber,
3. The joint structure of square timbers according to claim 1, wherein said pair of screws are obliquely driven with said corner metal fittings sandwiched therebetween. 4. In each side surface of said one square timber, the distance between said screws driven in with said corner fitting sandwiched therebetween is arranged at equal intervals on both side surfaces of said one square timber. A joint structure between rectangular timbers described. 5. The horizontal member according to any one of claims 1 to 4, characterized in that said screws are driven at an angle of 60[deg.] with respect to a surface of said other square timber orthogonal to a side surface of said one square timber. and pillar joint structure.

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