JP7771595B2 - wooden frame structure - Google Patents

Description

The present invention relates to wooden frame structures.

In wooden frame construction using the wooden frame method, the interior of a frame made up of wooden axial members such as wooden columns and wooden beams or foundations is generally made up of wooden panels such as structural plywood, which are joined with nails or braces to serve as load-bearing walls. If thick wooden panels such as CLT (Cross Laminated Timber) are used for these load-bearing walls, a large-wall format would result in the wall thickness of the frame being unnecessarily large, which would be uneconomical. Therefore, wood panels are arranged within the frame in a solid-wall format so that they fit within the width of the columns and beams of the frame.

When joining a frame and a wooden panel in this solid wall style, a common method is to attach a steel plate with a pinhole to a wooden axial member such as a beam or pillar, create a groove at the end of the wooden panel to accommodate the steel plate, and then abut the wooden axial member and the wooden panel while the steel plate is placed in the groove. After that, a connecting metal fitting such as a bolt or screw is inserted from the outside of the wooden axial member and passed through the pinhole to complete the join.

More specifically, the steel plate is a steel plate unit in which a steel plate (e.g., a first steel plate) fixed to the side of the wooden shaft member and a steel plate (e.g., a second steel plate) accommodated in the accommodation groove of the wooden panel are joined together by welding or other means, and the first steel plate is connected to the wooden shaft member, and the second steel plate is connected to the wooden panel using unique connecting hardware. In other words, when connecting wooden panels to a frame in a solid wall format, a steel plate unit is required instead of a single steel plate, and two types of connecting hardware are also required, which poses issues with the material cost and effort required for these connectors.

For these reasons, there is a need for technology that can reduce both the material costs and connection labor required for connectors in wooden frame structures where wooden panels are connected to the frame in a solid wall format.

Patent Document 1 proposes a CLT structure. This CLT structure includes a concrete foundation with horizontally extending reinforcing members, a wall panel made of laminated and glued planks with a longitudinally extending slit formed on its bottom surface, a connecting plate partially embedded in the foundation with at least a portion of its flat connecting plate protruding upward from the top surface of the foundation, and a connecting member consisting of a drift pin that connects the connecting plate to the wall panel when the connecting plate protruding from the top surface of the foundation is inserted into the slit in the wall panel. The connecting plate is positioned above the reinforcing members with its longitudinal direction aligned with the extension of the reinforcing members. The connecting plate includes the connecting plate, a flange embedded in the foundation and extending from the connecting plate in a direction intersecting the vertical direction, and an anchor embedded in the foundation and extending downward from the flange, with the lower end of the anchor member positioned below the reinforcing members.

Japanese Patent Application Laid-Open No. 2020-172743

Even in the CLT structure described in Patent Document 1, connecting wall panels to the foundation requires fittings consisting of a joint plate and a flange, and two types of fittings, namely, drift pins and anchor members, are still required.

The present invention was made in consideration of the above-mentioned problems, and aims to provide a wooden frame structure in which wooden panels are connected to the frame in a solid wall style, which reduces both the material costs required for connectors and the labor required for connections.

In order to achieve the above object, one aspect of the wooden frame structure according to the present invention is as follows:
A wooden frame structure formed by a frame including wooden columns and wooden beams or foundations,
The frame is characterized in that wooden panels are arranged in a solid wall format, and the wooden panels are fixed to the columns by axial fixing members that pass through the columns from the outer side of the column in the in-plane direction of the frame and lead to the inside of the wooden panels.

In this aspect, in a wooden frame structure in which wood panels are arranged in a solid wall format on the frame, the wood panels are fixed to the columns with axial fixing members that penetrate the columns from the outer side of the frame's in-plane direction and lead to the interior of the wood panels. This eliminates the need for steel plate units in which multiple steel plates are welded together, and since the columns and wood panels that make up the frame are fixed with a single type of axial fixing member, both the material costs and connection labor required for connectors can be reduced. Here, bolts, screws, nails, drift pins, etc. can be used as axial fixing members. Furthermore, structural plywood, laminated lumber (material in which multiple pieces of lumber are fixed with adhesives, screws, etc.), CLT panels, etc. can be used as wood panels.

Another aspect of the wooden framework according to the present invention is as follows:
The pillar is provided with a through hole,
An axial groove is provided from the end of the wood panel to the inside,
The through hole and the shaft-shaped groove are positioned to form a communication hole, and the shaft-shaped fixing member is inserted into the communication hole and driven in to be fixed.

In this aspect, a through-hole pre-drilled in the pillar and an axial groove pre-drilled in the wood panel are aligned with each other to form a communicating hole, and an axial fixing member is inserted into the communicating hole and hammered in and fixed, allowing the axial fixing member to be hammered into the desired hammering position with high precision and efficiency.

Another aspect of the wooden framework according to the present invention is as follows:
The wood panel is characterized in that it is fixed to the pillars on the left and right sides of the wood panel by the shaft-shaped fixing members, respectively.

According to this aspect, the wood panel is fixed to the pillars on either side of the panel, thereby increasing the fixing strength of the wood panel, which is fixed only to the pillars that make up the frame.

Another aspect of the wooden framework according to the present invention is as follows:
A first shear plate is embedded in the wood panel, and a portion of the first shear plate faces the interface between the wood panel and the column.
The shaft-shaped fixing member penetrates the first shear plate.

In this embodiment, the first shear plate is embedded in the wood panel facing the interface between the wood panel and the column, and the axial fixing member passes through the first shear plate to connect the column and the wood panel. This improves the shear strength of the axial fixing member and reduces the number of axial fixing members required. It is conceivable to embed the first shear plate in either the wood panel or the column, but since wood panels are generally softer than columns, it is preferable to embed it in the wood panel.

Another aspect of the wooden framework according to the present invention is as follows:
A second shear plate is embedded in the column, and a portion of the second shear plate faces the interface between the column and the wood panel;
The shaft-shaped fixing member penetrates both the second shear plate and the first shear plate.

In this configuration, in addition to embedding the first shear plate in the wood panel, the second shear plate is embedded in the column, and the first and second shear plates abut at the interface between the column and the wood panel. The axial fixing member penetrates the first and second shear plates to connect the column and the wood panel. This further improves the shear strength of the axial fixing member and makes it possible to further reduce the number of axial fixing members required.

Another aspect of the wooden framework according to the present invention is as follows:
The shaft-shaped fixing member is a drift pin.

In this embodiment, the axial fixing member is a drift pin, which increases the connection strength between the pillar and the wood panel. Furthermore, a drift pin is suitable as an axial fixing member that is inserted into and hammered into a communicating hole formed by positioning a through hole pre-installed in the pillar and an axial groove pre-installed in the wood panel.

In another aspect of the wooden frame structure according to the present invention,
The wooden panel and the beam or the base are fixed together by a tenon pipe.

In this embodiment, the wood panel and the beam or base are fixed together with the tenon pipe, so that the shear force generated in the wood panel can be borne by the tenon pipe.

Another aspect of the wooden framework according to the present invention is as follows:
The wood panel is a CLT panel.

In this embodiment, because the wood panels are CLT panels, a wide range of panels, for example up to 12m x 2.6m in length and width, can be used, minimizing the number of panel connections on-site. This improves the strength of wooden frame structures and construction efficiency. Furthermore, because CLT panels are made by stacking multiple boards with their fibers crossing (orthogonal), they are resistant to deformation and are suitable for use as load-bearing walls.

In another aspect of the wooden frame structure according to the present invention,
The front view shape of the wood panel is rectangular,
The four corners of the rectangle are cut out.

In this case, the four corners of the rectangular wooden panel, as viewed from the front, are notched. This prevents the corners of the wooden panel from coming into contact with beams, foundations, etc., and pressing against each other when the wooden frame structure is deformed during an earthquake, preventing an increase in load due to compressive forces.

As can be understood from the above explanation, the wooden frame structure of the present invention can reduce both the material costs and connection labor required for connectors in a wooden frame structure in which wooden panels are connected to the frame in a solid wall format.

1 is a front view showing an example of a wooden frame structure according to a first embodiment. FIG. 2 is a view taken along the line II-II in FIG. 1, illustrating the state in which the shaft-shaped fixing member fixes the pillar and the wood panel. 10A and 10B are diagrams illustrating a state in which a shear plate is provided at the interface between the pillar and the wood panel, and an axial fixing member fixes both of them. FIG. 1 is a perspective view of an example shear plate. FIG. 1 is a structural model diagram of an example of a wooden frame structure according to a first embodiment. FIG. 10 is a front view showing an example of a wooden frame structure according to a second embodiment. FIG. 10 is a structural model diagram of an example of a wooden frame structure according to a second embodiment.

An example of a wooden frame structure according to each embodiment will be described below with reference to the accompanying drawings. Note that in this specification and drawings, substantially identical components will be designated by the same reference numerals, and redundant explanations may be omitted.

[Wooden framework structure according to the first embodiment]
First, an example of a wooden frame structure according to the first embodiment will be described with reference to Figures 1 to 5. Here, Figure 1 is a front view showing an example of a wooden frame structure according to the first embodiment, and Figure 2 is a view taken along the line II-II in Figure 1, illustrating how the pillars and wooden panels are fixed by shaft-shaped fixing members.

The wooden frame structure 100 is formed by a framework 90 including wooden columns 10, wooden beams 20, and a foundation 30, and wooden panels 40 are arranged in a solid wall format on the framework 90. The illustrated example shows the framework 90 for the first floor of a building, but if the framework is for the upper floors of a two-story or higher building, the framework is formed by left and right columns and top and bottom beams.

The wood panel 40 is fixed to the left and right columns 10 with its left and right side surfaces 41 abutting against the columns 10 on the left and right, its top surface 42 abutting against the beams 20, and its bottom surface 43 abutting against the base 30. More specifically, the wood panel 40 is fixed to the columns 10 with drift pins 50 (an example of axial fixing members) that extend from the outer side surface 12 of the column 10 in the in-plane direction of the frame 90, through the column 10, and into the interior of the wood panel 40.

The wooden panel 40 has a rectangular shape when viewed from the front, with a height of h and a width of d. Structural plywood, laminated timber, CLT panels, etc. can be used for the wooden panel 40, but CLT panels are preferred because they can be used in a wide range of panels with dimensions up to 12m x 2.6m, and they minimize the number of connection points between panels on-site, which improves the strength of the wooden frame structure 100 and improves construction efficiency.

The center-to-center distance D between the left and right columns 10 is available in several configurations ranging from 0.5 m to 2.0 m, including, for example, 0.5 m, 0.75 m, 1.0 m, 1.5 m, and 2.0 m.

Notches 44 are provided at the four corners of the wooden panel 40. These notches 44 prevent the corners of the wooden panel 40 from coming into contact with the left and right columns 10, beams 20, and foundations 30 and increasing the load due to compressive forces caused by mutual pressure when a horizontal force F acts on the wooden frame structure 100 during an earthquake and causes deformation.

As shown in Figure 1, the height h1 of the cutout 44 is set to d/30 (1/30 radians) relative to the width d of the wood panel 40. According to the inventors' experience, setting the cutout 44 to 1/30 radians prevents the corners of the wood panel 40 from coming into contact with the beams 20 or foundation 30 when the frame 90 deforms during an earthquake, and this experience is the basis for this design.

Furthermore, the length of the central region of the upper surface 42 and lower surface 43 of the wood panel 40, excluding the left and right cutouts 44, is set to d/2 (the length of the cutouts 44 is set so that the length of the central region is d/2).

As shown in Figure 2, a through hole 15 is provided in the column 10, and an axial groove 45 is provided from the end of the wood panel 40 to the inside, and the through hole 15 and the axial groove 45 are positioned to form a communicating hole 18. Here, the lengths of the through hole 15 and the axial groove 45 are set to be the same or approximately the same.

The drift pin 50 is then inserted into the communication hole 18 and driven in to be fixed.

As shown in Figure 1, the left and right columns 10 and the wood panel 40 are fixed together by multiple drift pins 50. Here, the number of drift pins 50 on each side of the wood panel 40 can be determined using the following two calculation formulas.

Specifically, when a horizontal force F acts during an earthquake, the yield strength Py of the joint between the CLT panel and the column in a wooden frame structure 100 can be expressed by the following equation (1):

In equation (1), ny x py corresponds to the shear yield strength Qy of all the drift pins in Figure 1.

On the other hand, in the seismic performance of wooden buildings, the inter-story deformation angle during an earthquake: 1/150 is a general indicator, so the rigidity P ₁₅₀ of the joint between the CLT panel and the column can be expressed by the following equation (2).

The required number of drift pins 50 is determined by taking the smaller of the above equations (1) and (2) as the design strength.

Figures 3(a) and (b) show a joint configuration that improves the shear strength at the interface between the column 10 and the wood panel 40. Both Figures 3(a) and (b) illustrate a state in which a shear plate is provided at the interface between the column and the wood panel, and an axial fixing member secures both together.

In the configuration shown in Figure 3(a), a first shear plate 55A (shear plate 55) is embedded in the wood panel 40, and the first shear plate 55A faces the side surface 41 of the wood panel 40 (the interface with the column 10).

As shown in Figure 4, the shear plate 55 has a disk 55a with a pin hole 55c and a cylindrical wall 55b that stands along the outline of the disk 55a. The cylindrical wall 55b is embedded inside the wood panel 40, with the back surface of the disk 55a facing the interface with the column 10, and the drift pin 50 passes through the pin hole 55c and is embedded inside the wood panel 40.

On the other hand, in the configuration shown in Figure 3(b), in addition to a first shear plate 55A embedded in the wood panel 40, a separate second shear plate 55B (shear plate 55) is embedded in the column 10, and the disk 55a of the second shear plate 55B also faces the interface with the wood panel 40, with the backs of the disks 55a of the first shear plate 55A and the second shear plate 55B abutting each other at the interface. Drift pins 50 pass through the pin holes 55c of both disks 55a and are embedded inside the wood panel 40.

In either configuration shown in Figure 3(a) or (b), the use of one or two shear plates 55 improves the shear strength of the interface between the column 10 and the wood panel 40, making it possible to reduce the number of drift pins 50 required for design calculations.

The inventors conducted verification experiments to determine the load-bearing capacity per drift pin in the configuration reinforced with one shear plate 55 shown in Figure 3(a) and the configuration reinforced with two shear plates 55 shown in Figure 3(b).

As a result, in the configuration shown in Figure 3(a), the maximum load capacity is approximately 12 kN when the drift pin is displaced by approximately 5 mm, after which it begins to plastically deform.

On the other hand, in the configuration shown in Figure 3(b), the maximum load capacity reaches approximately 15 kN when the drift pin is displaced approximately 10 mm, after which it undergoes plastic deformation.

In other words, doubling the number of shear plates 55 only increases the load capacity by about 1.3 times, so from a cost-effectiveness perspective, reinforcing with a single shear plate 55 is preferable.

Furthermore, since the wood panel 40 is generally softer than the pillar 10, when one shear plate 55 is provided at the interface, it is preferable to embed the shear plate 55 in the wood panel 40, as shown in Figure 3(a).

Figure 5 is a diagram showing an example of a structural model of the wooden frame structure 100 shown in Figure 1. In the structural model M1, the joints (joints) of the column C to the beam B1 or foundation B2 can be joints such as tenons, mortise and tenon joints, or joints using connecting fittings such as tenon pipes, but all of these are represented by pins P1 in the structural model.

On the other hand, the connections between the left and right columns C and the wooden panel W using multiple drift pins can be modeled using springs Sp.

In the wooden frame structure 100 shown in Figure 1, the wooden panel 40 is fixed to the column 10 by a drift pin 50 that penetrates the column 10 from the outer side of the column 10 in the in-plane direction of the frame 90 and leads to the interior of the wooden panel 40. This eliminates the need for connecting jigs such as steel plate units, and allows the column 10 and wooden panel 40 to be fixed with a single type of axial fixing member, thereby reducing both the material cost and connection labor required for the connector.

[Wooden framework structure according to the second embodiment]
Next, an example of a wooden frame structure according to the second embodiment will be described with reference to Figures 6 and 7. Here, Figure 6 is a front view showing an example of a wooden frame structure according to the second embodiment.

The wooden frame structure 100A differs from the wooden frame structure 100 in that the wooden panels 40, beams 20, and foundations 30 are fixed together via tenon pipes 60.

The tenon pipe 60 has pin holes (not shown), and pins 65 such as drift pins are inserted into the pin holes to secure the tenon pipe 60 to the beam 20 and base 30, thereby securing the beam 20 and base 30 to the upper surface 42 and lower surface 43 of the wood panel 40.

In the illustrated example, two tenon pipes 60 are provided on each of the upper surface 42 and lower surface 43 of the wood panel 40, but the number of tenon pipes 60 is not limited to the illustrated example. Furthermore, when the diameter of the tenon pipe 60 is φ, the distance d2 between the two tenon pipes 60 is set to 5φ or more, and the distance d1 between the tenon pipe 60 and the cutout 44 is set to 2.5φ or more.

As shown in Figure 6, by fixing the top and bottom surfaces of the wood panel 40 to the beam 20 and base 30 with tenon pipes 60, the shear force S acting on the interface between the wood panel 40 and the beam 20, etc. when the frame 90 is deformed during an earthquake can be borne by the tenon pipes 60.

Figure 7 shows an example of a structural model of a wooden frame structure 100A. Structural model M2 can be created by adding pins P2, which model tenon pipes, to structural model M1 shown in Figure 5.

Note that other embodiments may be possible in which other components are combined with the configurations described in the above embodiments, and the present invention is in no way limited to the configurations shown here. In this regard, changes can be made without departing from the spirit of the present invention, and can be determined appropriately depending on the application form.

10: Pillar 11: Side 12: Side (outer side in the in-plane direction)
15: Through hole 18: Communication hole 20: Beam 30: Base 40: Wood panel (CLT panel)
41: Side surface 42: Upper surface 43: Lower surface 44: Notch 45: Axial groove 50: Axial fixing member (drift pin)
55: Shear plate 55A: First shear plate 55B: Second shear plate 55a: Disk 55b: Cylindrical wall 55c: Pin hole 60: Tenon pipe 65: Pin 90: Frame 100, 100A: Wooden framework frame F: Horizontal force Py: Yield strength Qy: Shear yield strength S: Shear force M1, M2: Structural model

Claims (8)

A wooden frame structure formed by a frame including wooden columns and wooden beams or foundations,
The frame has wood panels arranged in a solid wall format, and the wood panels are fixed to the columns by shaft-shaped fixing members that pass through the columns from the outer side surfaces of the columns in the in-plane direction of the frame and lead to the interior of the wood panels ;
A first shear plate is embedded in the wood panel, and a portion of the first shear plate faces the interface between the wood panel and the column.
A wooden frame structure, characterized in that the shaft-shaped fixing member penetrates the first shear plate. The pillar is provided with a through hole,
An axial groove is provided from the end of the wood panel to the inside,
The wooden frame structure described in claim 1, characterized in that the through hole and the axial groove are positioned to form a communicating hole, and the axial fixing member is inserted into the communicating hole and driven in to be fixed. A wooden frame structure as described in claim 1 or 2, characterized in that the wood panel is fixed to the columns on the left and right of the wood panel by the axial fixing members, respectively. A second shear plate is embedded in the column, and a portion of the second shear plate faces the interface between the column and the wood panel;
4. The wooden frame structure according to claim 1 , wherein the shaft-shaped fixing member penetrates both the second shear plate and the first shear plate. A wooden frame structure as described in any one of claims 1 to 4, characterized in that the axial fixing member is a drift pin. 6. The wooden frame structure according to claim 1, wherein the wooden panels and the beams or the foundations are fixed together by tenon pipes. The wooden frame structure according to any one of claims 1 to 6 , wherein the wood panels are CLT panels. The front view shape of the wood panel is rectangular,
The wooden frame structure according to any one of claims 1 to 7 , wherein four corners of the rectangle are cut out.