JP7574249B2 - Joint structure - Google Patents

Description

The present invention relates to a joint structure between a pillar and a beam.

When joining wooden members in a wooden rigid frame structure with wooden columns and beams, it is common to insert a steel member protruding from one wooden member, such as a glue-in rod (GIR), into a hole in the other wooden member in the axial direction, and fill the hole with a filler such as an adhesive to rigidly join the wooden members together (see, for example, Patent Document 1).

Patent Publication No. 2022-8273

Generally, the fiber direction of columns and beams is perpendicular to that of other components, so if the above method is applied to the joints between columns and beams, the GIR or other steel material will be inserted perpendicular to the fiber of one of the components, creating the problem that the strength of the frame will be determined by the strength in the perpendicular direction, which is weaker than the fiber direction.

Furthermore, wooden components may need to be fire-resistant, in which case the surface must be covered with a fire-resistant coating, but this does not bring out the inherent beauty of wooden construction.

In addition, when the above-mentioned method is used to join wooden members together, it becomes necessary to move the wooden member in the axial direction in order to insert the steel material into the hole in the wooden member. In particular, when the wooden member is a beam, there is often not enough space to move it in the axial direction of the beam, making construction difficult. Also, when drilling holes in the axial direction of the wooden member, there is a limit to how far the hole can be drilled in the depth direction due to the drilling technology (for example, the length of the drilling tool), and the length to which the steel rod can be fixed is limited by the drilling limit.

The present invention was made in consideration of the above-mentioned problems, and its purpose is to provide a column-beam joint structure that is excellent in terms of strength and design.

The first invention for achieving the above-mentioned object is a column-beam joint structure, wherein the column is constructed by filling the inside of an exterior timber located on the outer periphery with concrete, the beam is joined to the side of the column, a steel rod protruding horizontally outward from the column is inserted into the beam , an opening is formed on the side of the exterior timber at a position corresponding to the beam, the steel rod is passed through the opening, and the opening is filled with concrete .

In the first invention, the columns are made of a composite structure of concrete and wood, and the steel rods protruding from the columns are inserted into the beams to join the columns and the beams. This allows the columns to have an exposed wood exterior, making them a structural frame with excellent design, and the columns have excellent fire resistance because they have concrete inside. In addition, because concrete is used for the columns, it is possible to avoid the strength issues that arise when steel rods are arranged perpendicular to the grain, as mentioned above, and a structural frame with excellent strength can be obtained.
In addition, by creating openings on the sides of the exterior timber at positions corresponding to the beams and filling these openings with concrete, it becomes easier to increase the rigidity and strength of the joint structure, and construction is also made easier by placing steel rods through the openings.

The opening may be a closed area surrounded entirely by the outer wood.

The second invention is a joint structure between a pillar and a beam, wherein the pillar is constructed by filling the inside of an outer casing timber located on the periphery with concrete, the beam is joined to the side of the pillar, a steel rod protruding horizontally outward from the pillar is inserted into the beam, the beam is formed by combining a plurality of wooden members divided by planes parallel to the beam axis direction, a groove is formed on at least one of the opposing surfaces of the wooden members, and the steel rod is arranged in the groove.
In the second invention, the columns are made of a composite structure of concrete and wood, and the steel rods protruding from the columns are inserted into the beams to join the columns and the beams. This allows the columns to have an exposed wood exterior, making them a structural frame with excellent design, and the columns have excellent fire resistance because they have concrete inside. In addition, because concrete is used for the columns, it is possible to avoid the strength issues that arise when steel rods are arranged perpendicular to the grain, as mentioned above, and a structural frame with excellent strength can be obtained.
In addition, by constructing a beam from multiple wooden members divided by planes parallel to the beam axis direction and placing steel rods in grooves formed in the surfaces of the wooden members, it is not necessary to move the wooden members in the beam axis direction when installing the beam, making construction easier. In addition, there is no need to drill holes in the wooden members in the beam axis direction, making pre-processing easier and eliminating the restriction on the length of the groove from the perspective of processing technology.

For example, the beam may be a double beam, each of the two beams of the double beam being formed by combining two wooden members divided by a vertical plane parallel to the beam axis direction, and the groove may be formed in each of the two wooden members.
This allows the number of steel bars to be increased, increasing the strength of the beam. In addition, after the wooden members are dropped in, they can be moved horizontally to set the beams, making it easier to erect the wooden members.

The third invention is a joint structure between a pillar and a beam, the pillar being constructed by filling the inside of an outer casing timber located on the outer periphery with concrete, the beam being joined to the side of the pillar, a steel rod protruding horizontally outward from the pillar being inserted into the beam, main reinforcement bars being embedded in the concrete of the pillar, and hoop reinforcement being omitted within the concrete.
In the third invention, the columns are made of a composite structure of concrete and wood, and the steel rods protruding from the columns are inserted into the beams to join the columns. This allows the columns to have an exposed wood exterior, making them a structural frame with excellent design, and the columns have excellent fire resistance because they have concrete inside. In addition, because concrete is used for the columns, it is possible to avoid the strength issues that arise when steel rods are placed perpendicular to the fibers, as mentioned above, and a structural frame with excellent strength can be created.
In addition, the inside of the pillars can be made of reinforced concrete with main bars embedded in the concrete, improving the structural performance of the pillars. In addition, in the third invention, it is possible to give the exterior wood a shear reinforcement function, and hoop reinforcement can be omitted.

The present invention can provide a column-beam joint structure that is excellent in terms of strength and design.

FIG. A diagram showing the cross-section of a column 2 and a beam 4. 4A to 4C are diagrams showing a method of constructing the joint structure 1. 4A to 4C are diagrams showing a method of constructing the joint structure 1. 4A to 4C are diagrams for explaining a method of installing wooden members 41. FIG. 2 is a diagram showing joint structures 1a and 1b. Diagram showing precast columns. FIG. FIG. FIG.

The following describes in detail an embodiment of the present invention with reference to the drawings.

(1. Joint structure 1)
Fig. 1(a) is a diagram showing a rigid frame structure including a joint structure 1 according to an embodiment of the present invention. This structure is a structure for the periphery of a building, and has a rigid frame structure with a single structural plane composed of columns 2 and beams 4. A concrete slab 5 is provided on the beams 4. The columns 2, beams 4, and slabs 5 are provided on multiple floors, one above the other. In this example, the height of the beams 4 on each floor is lower than the top end of the columns 2 on each floor by about the thickness of the slab 5, but there are also cases where the slab 5 is not provided on the beams 4, and in such cases, the beams 4 on each floor can be located at a higher position.

The joint structure 1 of this embodiment joins a column 2 and a beam 4. FIG. 1(b) is a perspective view showing the joint structure 1. In the joint structure 1, a beam 4 is joined to the side of the column 2. The beam 4 is positioned slightly below the upper end of the column 2. Note that FIG. 1(b) omits the illustration of the upper layer column 2 stacked on top of the column 2 and the slab 5 placed on top of the beam 4 in the figure.

Figure 2 shows the cross sections of the column 2 and beam 4 for the joint structure 1 in Figure 1(b). Figure 2(a) is a vertical cross section of the column 2 and beam 4, and Figure 2(b) is a horizontal cross section of the column 2 and beam 4. Figure 2(c) is a horizontal cross section of the column 2, and Figure 2(d) is a vertical cross section of the beam 4. Figures 2(b) and (c) are cross sections taken along lines a-a and b-b in Figure 2(a), respectively, and Figure 2(a) is a cross section taken along line c-c in Figure 2(b). Figure 2(d) is a cross section taken along line d-d in Figure 2(b).

The pillar 2 is a composite structural pillar made of concrete C and wood, and its horizontal cross section is rectangular. However, the cross-sectional shape of the pillar 2 is not limited to this, and it may be other polygonal or circular shapes. The pillar 2 has an outer shell 21 on the outer periphery, main reinforcement 22 is placed inside, and concrete C is filled in.

The exterior timbers 21 are made of wood boards such as LVL (Laminated Veneer Lumber) and CLT (Cross Laminated Timber). Four exterior timbers 21 are arranged corresponding to each side of the rectangular cross section, and the ends of the exterior timbers 21 are joined together at the corners of the cross section with bolts 23 such as lag screw bolts. Note that other wood materials such as laminated timber and BP material can also be used as the exterior timbers 21.

The exterior timbers 21 improve the design by forming the exterior appearance of the column 2, and also function as a formwork when filling with concrete C. In this embodiment, opposing exterior timbers 21 are connected by separators 24 to resist the lateral pressure when filling with concrete C. Hoop reinforcement is omitted in the concrete C, and instead of hoop reinforcement, the exterior timbers 21 and separators 24 function as shear reinforcement members. The exterior timbers 21 exert a shear reinforcement function due to their in-plane rigidity.

In addition to the formwork and shear reinforcement functions described above, the outer shell timber 21 is also expected to act as a fire repellent in the event of a fire, thereby compensating for the fire resistance of columns 2 that do not have hoop reinforcement (there is a risk of the fire resistance of the concrete section being reduced by omitting hoop reinforcement). For this reason, it is desirable for the thickness of the outer shell timber 21 to be the minimum thickness that can resist the lateral pressure when concrete C is poured, has sufficient in-plane rigidity, and still function as a fire repellent.

In this embodiment, an opening 211 is provided in the exterior wood 21 at a position corresponding to the beam 4 on the side of the column 2, and concrete C is also filled into this opening 211. The opening 211 is provided only at a position corresponding to the beam 4 on the side of the column 2.

In addition, at the joint between the column 2 and the beam 4, steel bars 25 such as reinforcing bars are embedded in the column 2. The steel bars 25 are arranged horizontally, with both ends protruding outward through openings 211 in the opposing exterior wood 21. In this embodiment, the steel bars 25 are arranged in two tiers, one above the other.

The ends of the steel bars 25 are inserted inside the beams 4. The beams 4 are double beams arranged in a front-to-back pair with a gap between them, and are arranged so that the end faces of the beams 4 abut against the concrete C filled in the openings 211. The front-to-back direction is a direction perpendicular to the structural surface of the columns 2 and beams 4, and corresponds to the normal direction to the paper surface in FIG. 2(a), the up-down direction in FIG. 2(b) and (c), and the left-to-right direction in FIG. 2(d). The openings 211 and steel bars 25 are also provided in a front-to-back pair corresponding to the front and back beams 4, respectively.

The beam 4 is formed from two wooden members 41 divided by a vertical plane parallel to the beam axis direction. Grooves 411 are formed on the opposing surfaces of these wooden members 41, and by combining the wooden members 41 in the beam 4, the grooves 411 of each wooden member 41 form a space for inserting the end of the steel rod 25. The end of the steel rod 25 is placed in this space and filled with a filler 412 such as an adhesive, so that the end of the steel rod 25 is fixed to the beam 4 and the column 2 and the beam 4 are joined. The wooden members 41 are integrated with each other by a joining means such as a bolt (not shown). The wooden members 41 are also provided in advance with an injection hole (not shown) for filling the filler 412.

(2. Method for constructing joint structure 1)
When constructing the joint structure 1, first, the main reinforcement 22 of the column 2 is erected as shown in Fig. 3(a), and then, as shown by the arrow e, the exterior timbers 21, which have been assembled in advance into a cylindrical shape and made into a unit, are dropped from above and erected. Fig. 3(b) shows the state after the exterior timbers 21 have been erected.

Next, as shown in FIG. 3(c), concrete C is poured and filled up to a position slightly below the opening 211, and as shown in FIG. 4(a), steel bars 25 are passed through the opening 211 and placed in the specified position. Then, wooden members 41 are erected from above as shown by arrow f in FIG. 4(a), and beams 4 are installed as shown in FIG. 4(b).

When erecting the wooden members 41, first, as shown in Figure 5(a), the wooden members 41 are dropped to the side of the steel rod 25, avoiding the steel rod 25, and then each wooden member 41 is moved horizontally forward or backward as shown by arrows g to j, and the opposing faces of a pair of wooden members 41 are brought into contact with each other so that the steel rod 25 is sandwiched between the grooves 411, as shown in Figure 5(b). The wooden members 41 are then integrated with bolts or the like, and the space formed by the grooves 411 of both wooden members 41 is filled with filler material 412. Note that Figures 5(a) and (b) show the same cross section as Figure 2(d), and this also applies to Figures 8 to 10 described below.

As shown in Figure 2(d), in this embodiment, the beams 4 are double beams, and there is a gap between the front and rear beams 4, so there is enough space for the wooden members 41 located on the other side of each beam 4 to be dropped in and moved horizontally as described above (see arrows h and i in Figure 5(a)).

After installing the beam 4 as shown in FIG. 4(b), concrete C is poured up to the height of the upper end of the column 2, thereby constructing the joint structure 1 between the column 2 and the beam 4 as shown in FIG. 2(a) etc. In this embodiment, a new column 2 is installed on top of this column 2 to construct a further upper layer of the structure. In FIG. 2(a), the main reinforcement 22 protrudes above the column 2, but the main reinforcement 22 of the column 2 on the upper layer is connected to this protruding portion using a mechanical joint or the like.

In this way, in this embodiment, the pillar 2 is a composite structure of concrete C and wood, and the pillar 2 and the beam 4 are joined by inserting the steel rod 25 protruding from the pillar 2 into the beam 4. As a result, in this embodiment, the exterior of the pillar 2 is exposed wood, making it a structural frame with excellent design, and the pillar 2 has excellent fire resistance because it has concrete C inside. In addition, the exterior wood 21 functions as a fuel substitute, suppressing the temperature rise of the concrete C, which also has the effect of preventing the concrete C from exploding.

In addition, in this embodiment, concrete C is used for the columns 2, and as described above, the steel bars 25 are arranged in the direction perpendicular to the fibers, which avoids the strength issues that arise, resulting in a frame with excellent strength. By stabilizing the rigidity and strength of the joints between the columns 2 and the beams 4, a rigid frame can be obtained that can ensure good performance against repeated loads during earthquakes. In addition, costs can be reduced compared to constructing the columns 2 only from wood.

In this embodiment, openings 211 are provided in the exterior wood 21 at positions corresponding to the beams 4, and the openings 211 are filled with concrete C, which makes it easier to bring the beams 4 into contact with the concrete C and increase the rigidity and strength of the joint structure 1. Also, by placing the steel rods 25 through the openings 211, construction is also made easier.

In addition, in this embodiment, by placing the steel rod 25 in the groove 411 formed in the surface of the wooden member 41, there is no need to move the wooden member 41 in the beam axial direction when installing the beam 4, making construction easier. There is also no need to drill holes in the wooden member 41 in the beam axial direction, making pre-processing easier and there is no restriction on the length of the groove 411 in terms of processing technology.

In addition, in this embodiment, by making the beam 4 a double beam, the number of steel bars 25 can be increased to increase the strength of the beam 4. In addition, the two wooden members 41, which are divided by a vertical plane parallel to the beam axis direction, can be dropped in and then moved horizontally to install the beam 4, making it easier to erect the wooden members 41.

In this embodiment, the interior of the pillar 2 is made of reinforced concrete with main bars 22 embedded in the concrete C, improving the structural performance of the pillar 2. In this embodiment, the exterior wood 21 can also be given a shear reinforcement function, making it possible to omit hoop reinforcement.

However, the present invention is not limited to the above embodiment. For example, in this embodiment, after the main reinforcement 22 is placed, the unitized exterior timber 21 is dropped in, which reduces construction costs, but the main reinforcement 22 and exterior timber 21 units may be dropped in and installed at the same time. In this case, dropping in the main reinforcement 22 with the lower end of the exterior timber 21 protruding downwards can ensure working space for connecting the main reinforcement 22 to the main reinforcement 22 of the column 2 on the lower level.

In addition, instead of dropping the units of the exterior timbers 21 into the building, the main reinforcement bars 22 may first be placed, and then the exterior timbers 21 may be installed from the side and assembled. In this case, hoop reinforcement may also be provided on the columns 2. On the other hand, when dropping the units of the exterior timbers 21 into the building, it is difficult to provide hoop reinforcement on the columns 2, as the separators 24 will interfere with the hoop reinforcement.

As shown in the joint structure 1a in FIG. 6(a), a steel plate 26 may be placed in the opening 211 of the exterior wood 21 of the column 2a to close the opening 211, and the end face of the beam 4 may be abutted against the steel plate 26. In this case, the steel plate 26 functions as a formwork when filling the concrete C, improving the formwork performance of the wooden member 41 and preventing a decrease in the rigidity and strength of the joint structure 1a. Alternatively, as shown in the joint structure 1b in FIG. 6(b), the opening 211 of the exterior wood 21 of the column 2b may be omitted, and the end face of the beam 4 may be abutted against the exterior wood 21. In this case, fine processing can be omitted, making it easier to manufacture the exterior wood 21. In the case of FIG. 6(a), the steel rod 25 penetrates the steel plate 26, and in the case of FIG. 6(b), the steel rod 25 penetrates the exterior wood 21.

In addition, an energy absorbing material such as a viscoelastic body may be placed in the opening 211 of the outer wood 21 and the end face of the beam 4 may be abutted against it, thereby improving the vibration damping performance of the entire frame.

Also, as shown in Figure 7(a), the exterior wood 21, main reinforcement 22, and concrete C up to a height slightly below the opening 211 can be precast in a factory or the like, and then transported and installed at the site. After this, the steel rods 25 are placed and the steps from Figure 4(a) onwards are carried out to construct the joint structure 1.

Also, as shown in FIG. 7(b), the main reinforcement 22, the exterior timbers 21 up to a height slightly below the beams 4, and the concrete C may be fabricated in advance as precast columns in a factory or the like, and then transported and installed at the site. After this, the exterior timbers 21 and steel bars 25 are placed above the exterior timbers 21, and the steps in and after FIG. 4(a) are carried out, whereby the joint structure 1 is constructed.

Also, as shown in FIG. 7(c), the main reinforcement 22, the outer timber shell 21 that runs the entire length of the column 2, and the concrete C may be fabricated in advance as a precast column in a factory or the like, and then transported and installed at the site. After this, the steel rod 25 is placed, and the beam 4 is installed by carrying out the steps in FIG. 4(a) and (b), thereby constructing the joint structure 1. A through hole T for passing the steel rod 25 through is formed in advance in the concrete C of the precast column. Alternatively, the steel rod 25 may be integrated into the precast column in advance.

In addition, in this embodiment, the beams 4 are arranged in pairs at the front and back to form a double beam, but this is not limited to this, and one beam 4 may be arranged on each side of the column 2. Also, the wooden member 41 is formed by dividing the beam 4 into two by a vertical plane parallel to the beam axis direction, but for example, as shown in Figure 8 (a), one beam 4a arranged on the side of the column 2 may be composed of three wooden members 41 divided by a horizontal plane parallel to the beam axis direction. In this case, grooves 411 are formed only in the top and bottom two wooden members 41, and no groove 411 is provided in the middle wooden member 41.

When installing the beam 4a, each wooden member 41 is moved horizontally to avoid the steel rods 25, and as shown in FIG. 8(b), the upper wooden member 41 is placed above the upper steel rod 25, the lower wooden member 41 is placed below the lower steel rod 25, and the middle wooden member 41 is placed between the upper and lower steel rods 25. After that, the upper and lower wooden members 41 are moved vertically toward the middle wooden member 41, so that the steel rods 25 are placed in the grooves 411 of the upper and lower wooden members 41.

Also, as shown in FIG. 9(a), one beam 4b arranged on the side of the column 2 may be composed of three wooden members 41 divided by a vertical plane parallel to the beam axis direction. In this case, grooves 411 are formed only in the two front and rear wooden members 41 (the left and right wooden members 41 in FIG. 9(a)), and no groove 411 is provided in the middle wooden member 41.

When installing the beam 4b, each wooden member 41 is dropped from above, avoiding the steel bars 25, and as shown in FIG. 9(b), the front wooden member 41 is placed in front of the front steel bar 25, the rear wooden member 41 is placed behind the rear steel bar 25, and the middle wooden member 41 is placed between the front and rear steel bars 25. After that, the front and rear wooden members 41 are moved horizontally toward the middle wooden member 41, so that the steel bars 25 are placed in the grooves 411 of the front and rear wooden members 41.

In addition, in this embodiment, the beam 4 is made of wood, but it may be made of reinforced concrete, or, like the column 2, it may be a composite structure made of concrete and wood. Figure 10 shows an example of a beam 4c having a composite structure, in which the end of a steel rod 25 is placed inside a concavely arranged wooden member 42 and filled with concrete C.

The joint structure 1 of this embodiment is intended to be applied to the single-panel rigid frame structure shown in FIG. 1(a) on the periphery of a building, but it may also be applied inside a building to the joints of the rigid frame structure in two directions, the plane shown in FIG. 1(a) and a plane perpendicular to that plane. In this case, beams 4 are also provided in front and behind the column 2, and steel bars 25 are also arranged in the front-to-back direction.

The above describes preferred embodiments of the present invention with reference to the attached drawings, but the present invention is not limited to these examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the technical ideas disclosed in this application, and it is understood that these also naturally fall within the technical scope of the present invention.

1, 1a, 1b: Joint structure 2, 2a, 2b: Columns 4, 4a, 4b, 4c: Beam 21: Outer wood 22: Main reinforcement 25: Steel rod 26: Steel plate 41: Wooden member 211: Opening 411: Groove C: concrete

Claims (6)

A column-beam joint structure,
The pillars are constructed by filling the inside of the outer timber shell located on the outer periphery with concrete,
The beam is joined to the side of the column,
A steel rod protruding horizontally outward from the column is inserted into the beam ;
An opening is formed in a side surface of the exterior wood at a position corresponding to the beam,
The steel rod is passed through the opening;
A joint structure characterized in that the opening is filled with the concrete . 2. The joint structure according to claim 1, wherein the opening is a closed area surrounded by the outer wooden shell on its entire periphery. The joint structure according to claim 1 , characterized in that a steel plate is disposed in the opening. A column-beam joint structure,
The pillars are constructed by filling the inside of the outer timber shell located on the outer periphery with concrete,
The beam is joined to the side of the column,
A steel rod protruding horizontally outward from the column is inserted into the beam ;
The beam is formed by combining a plurality of wooden members divided by planes parallel to the beam axis direction,
A joint structure characterized in that a groove is formed in at least one of the opposing surfaces of the wooden members, and the steel rod is placed in the groove . The beam is a double beam, and each of the two beams of the double beam is formed by combining two wooden members divided by a vertical plane parallel to the beam axis direction,
5. The joint structure according to claim 4, wherein said grooves are formed in each of said two wooden members. A column-beam joint structure,
The pillars are constructed by filling the inside of the outer timber shell located on the outer periphery with concrete,
The beam is joined to the side of the column,
A steel rod protruding horizontally outward from the column is inserted into the beam ;
A joint structure characterized in that main reinforcement is embedded in the concrete of the column and hoop reinforcement is omitted within the concrete .

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