Joint structure

Abstract

To provide a joint structure, etc. that can realize a framework with excellent strength.SOLUTION: A joint structure 1 joins a column 2 and a beam 4 via a joint portion 3 having a concrete portion. The beam 4 has an end beam 41 provided on a side of the joint portion 3 and an intermediate beam 42 continuous with the end beam 41. The intermediate beam 42 is a beam-shaped member made of wood, and the end beam 41 has a concrete portion. The joint section 3 and the end beam 41 are an integral precast member with a horizontal joint reinforcing bar 31 embedded across the joint section 3 and the concrete portion of the end beam 41, and the precast member and the intermediate beam 42 are joined using the joint reinforcing bar 31.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a column-to-beam joint structure. [Background technology]

[0002] When joining wooden members in a wooden rigid frame structure with wooden columns and beams, a common method is to insert a steel member, such as a GIR (Glued-In Rod), protruding from one wooden member into a hole in the other wooden member in the axial direction. By filling the hole with a filler such as an adhesive, the wooden members can be joined together (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-8273 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the fiber direction of columns and beams is generally perpendicular, if the above construction method is applied to the joint between a column and a beam, steel materials such as GIR will be inserted perpendicular to the fiber of one of the components, which will pose a strength issue.

[0005] The present invention has been made in view of the above-mentioned problems, and has an object to provide a joint structure etc. that can realize a frame having excellent strength. [Means for solving the problem]

[0006] The first invention for solving the above problem is a joint structure in which a column and a beam are joined via a joint having a concrete portion, the beam having an end beam provided on the side of the joint and an intermediate beam continuous with the end beam, the intermediate beam being a beam-shaped member made of wood, the end beam having a concrete portion, the joint and the end beam being an integral precast member in which horizontal joining steel bars are embedded so as to straddle the joint and the concrete portion of the end beam, and the precast member and the intermediate beam are joined using the joining steel bars.

[0007] In this invention, the beam is divided into end beams and intermediate beams, and environmentally and aesthetically superior wood materials are used for the intermediate beams, while reinforced concrete is used for the beam-column joints and end beams. This avoids the problem of rebar being inserted perpendicular to the grain of the wooden members. Furthermore, by using reinforced concrete for the end beams, which allows the reinforced concrete to exert its toughness, a highly ductile frame with flexural yielding properties can be realized against repeated loads such as those during earthquakes. This allows for a frame with excellent strength. Furthermore, by making the joints and end beams into integral precast members, construction is also easier.

[0008] The pillars may be made of reinforced concrete, or may be made of wood or may have a composite structure with concrete filled inside a wooden shell. The columns can be made of reinforced concrete, wood, or a composite structure of concrete and wood exterior, and the type of structure the columns should be made of can be determined taking into consideration strength, fire resistance, environmental aspects, and design aspects.

[0009] It is also preferable that the joints and the end beams have a composite structure in which concrete is filled inside the outer timber shell. This allows the strength of the components to be maintained by the concrete, while leaving the wood exposed allows the original beauty of wooden construction to be expressed in the joints and end beams.In addition, by using reinforced concrete for the interior, there is no need for fire-resistant coating on the exterior wood, reducing construction labor and costs. [Effects of the Invention]

[0010] The present invention can provide a joint structure or the like that can realize a frame with excellent strength. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram showing a joint structure 1. FIG. [Figure 2] 1A and 1B are diagrams showing a method for constructing the joint structure 1. [Figure 3] FIG. 10 is a diagram showing a joint 3a and an end beam 41a. [Figure 4] An example of beam 4 being a double beam. [Figure 5] FIG. 2 is a diagram showing a joint structure 1a. [Figure 6] FIG. [Figure 7] FIG. 1B is a diagram showing a joint structure 1b. [Figure 8] 10A and 10B are diagrams showing a method for constructing the joint structure 1b. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0013] [First embodiment] (1.Joint structure 1) 1(a) and (b) are diagrams showing a joint structure 1 according to a first embodiment of the present invention. Fig. 1(a) is a diagram showing the joint structure 1 as seen from the front, and Fig. 1(b) is a horizontal cross section taken along line AA in Fig. 1(a).

[0014] The joint structure 1 of this embodiment joins a column 2 and a beam 4 at a joint (panel zone) 3.

[0015] The columns 2 are reinforced concrete members, and are arranged above and below the joint 3. The cross section perpendicular to the material axis direction (hereinafter simply referred to as the cross section) is rectangular. However, the cross-sectional shape of the columns 2 is not limited to this, and may be other polygonal or circular shapes. Vertical reinforcing bars 21 (main reinforcing bars) are embedded inside the columns 2, and the lower ends of the reinforcing bars 21 are inserted into the upper parts of sleeves 24 embedded in the lower ends of the columns 2.

[0016] The joint 3 is a reinforced concrete member. In this embodiment, the horizontal cross section of the joint 3 corresponds to the cross section of the column 2, and the joint 3 is positioned within the range of the cross section of the column 2. In addition, end beams 41 are provided on the left and right sides of the joint 3. The end beams 41 are reinforced concrete members, and the joint 3 and the end beams 41 are fabricated in advance as a single unit in a factory or the like as precast members.

[0017] The upper part of the reinforcing bar 21 of the column 2 below the joint 3 protrudes upward from the column 2, passes vertically through a through-hole 34 in the joint 3, and protrudes further upward from the joint 3. A sheath or the like is used in the through-hole 34, and a filler 35 is filled inside. The filler 35 is, for example, mortar or resin, but is not limited to these. The protruding part of the reinforcing bar 21 from the joint 3 is inserted into the lower part of the sleeve 24 of the column 2 above the joint 3. The column 2 above the joint 3 is joined to the joint 3 by filling the sleeve 24 with a filler (not shown) such as mortar or resin.

[0018] The beams 4 are members provided on the left and right sides of the joint 3, and are composed of the end beams 41 and intermediate beams 42. The intermediate beams 42 are arranged so as to be continuous with the end beams 41. Although not shown in the figures, in this embodiment, a reinforced concrete slab is provided on the beams 4, and the intermediate beams 42 can also be used as a composite beam frame with the slab.

[0019] The intermediate beam 42 is a wooden component, a beam-shaped precast component formed entirely from wooden materials. Examples of the wooden material include, but are not limited to, laminated lumber. Although not specifically shown, a fire-retardant layer is provided on both sides and the bottom of the intermediate beam 42 to ensure the fire resistance of the intermediate beam 42. The top surface of the intermediate beam 42 is in contact with the concrete slab, so a fire-retardant layer is not necessary, but depending on the frame, a fire-retardant layer may be provided on the top surface of the intermediate beam 42. The fire-retardant layer is formed by impregnating wood with a fire-retardant agent, but is not limited to this, and other fire-resistant components may also be used. In some cases, the fire-retardant layers on both sides and the bottom of the intermediate beam 42 may be omitted.

[0020] In this embodiment, horizontal connecting rebars 31 are embedded so as to straddle the concrete portions of the joint 3 and the end beams 41, and both ends of the connecting rebars 31 protrude from the end beams 41 on the left and right sides of the joint 3 toward the intermediate beams 42 that are continuous with the end beams 41. These protruding portions are inserted into holes 43 provided at the ends of the intermediate beams 42 in the material axis direction. By filling the holes 43 with a filler (not shown) such as mortar or resin, the precast members of the joint 3 and the end beams 41 and the intermediate beams 42 are joined using the connecting rebars 31.

[0021] (2. Construction method of joint structure 1) When constructing the joint structure 1, first, the column 2 is provided below the joint 3, as shown in Figure 2(a). In this embodiment, the column 2 is a precast member, and is manufactured in a factory or the like, transported to the site, and erected and installed at the construction location. However, the column 2 may also be made of cast-in-place concrete, in which case reinforcing bars 21 and the like are arranged at the construction location, a formwork is assembled, and the column 2 is formed by pouring concrete into the formwork.

[0022] Thereafter, as shown in Figure 2(b), the joint 3 and end beam 41, which have been fabricated as a single precast member in a factory or the like, are transported to the site and dropped into the construction location from above as indicated by the arrow, and as shown in Figure 2(c), the protruding parts of the reinforcing bars 21 from the column 2 are passed through the through holes 34 and installed on top of the column 2. The through holes 34 are filled with the above-mentioned filler 35 (see Figure 1(b)).

[0023] Then, the intermediate beam 42 manufactured at a factory or the like is transported to the site and moved in the direction of its material axis toward the end beam 41 as shown by the arrow. As shown in Figure 2(d), the protruding part of the connecting reinforcing bar 31 from the end beam 41 is inserted into the hole 43 of the intermediate beam 42, and the filler material (not shown) is filled into the hole 43.

[0024] Then, as shown by the arrow, the column 2 is dropped in from above the joint 3, and the protruding portion of the reinforcing bar 21 protruding from the joint 3 is inserted into the lower part of the sleeve 24 of the column 2. The joint structure 1 shown in Figure 1 is constructed by filling the sleeve 24 with a filler material (not shown). Note that the column 2 above the joint 3 can also be formed from cast-in-place concrete, as described above. In this case, the sleeve 24 of the column 2 can be omitted.

[0025] As explained above, according to this embodiment, the beam 4 is divided into the end beams 41 and intermediate beams 42, and environmentally and aesthetically pleasing wood material is used for the intermediate beam 42, while reinforced concrete is used for the joints 3 and end beams 41. This avoids the problem of reinforcing bars being inserted perpendicular to the grain of the wooden members. Furthermore, by using reinforced concrete for the end beams 41, which allows the reinforced concrete to exert its toughness, a highly ductile frame with flexural yielding properties against repeated loads during earthquakes can be realized. This allows for a frame with excellent strength. Furthermore, by making the joints 3 and end beams 41 into a single precast member, construction is also easier.

[0026] However, the present invention is not limited to the above embodiment. For example, as shown in Fig. 3, which is a cross section similar to Fig. 1(b), the end beam 41a may have a composite structure of outer timber 411 and concrete 412, and the joint 3a may have a composite structure of outer timber 32 and concrete 33.

[0027] The exterior timbers 411 are plank-shaped wooden materials arranged to cover both sides and the bottom of the end beams 41a, and the inside of these is filled with concrete 412. The exterior timbers 411 function as shear reinforcement for the end beams 41a and as formwork when pouring the concrete 412 in a factory or the like, and also serve as burners that contribute to the fire resistance of the reinforced concrete inside. Furthermore, by leaving the wood exposed while maintaining the strength of the components with the concrete 412, the original beauty of wooden construction can be expressed.

[0028] Glued laminated timber, CLT, BP material, etc. can be used for the exterior timber 411. The material and thickness of the exterior timber 411 are determined so that it has sufficient in-plane strength to function as a shear reinforcement, can resist the out-of-plane pressure when the concrete 412 is poured, and contributes to fire resistance by acting as a fire barrier. By constructing the inside of the exterior timber 411 out of reinforced concrete, the fire resistance of the exterior timber 411 (in an unburned state) is not particularly necessary, and fire-resistant coating, etc. is not necessary, which reduces construction effort and costs.

[0029] The outer timbers 32 of the joint 3a are also made of plank-shaped wood materials such as laminated timber, CLT, and BP material, and are arranged so as to cover all sides of the joint 3a except for the boundary with the concrete 412 of the end beam 41a. Concrete 33 is filled inside the outer timbers 32. The outer timbers 32 have the same functions and roles as the outer timbers 411 described above.

[0030] It is also possible to use a composite structure of exterior timbers 32, 411 and concrete 33, 412 for only either the joint 3a or the end beam 41a.

[0031] 1(b), the beam 4 may be a double beam, with a pair of beams 4 spaced apart in the beam width direction on either side of the joint 3. This allows the cross section of the beam 4 to be smaller, reducing the cost required for the beam 4. The beam width direction is the direction perpendicular to the material axis direction of the beam 4 in a plan view, and corresponds to the up-and-down direction in FIG. 4.

[0032] In addition, in this embodiment, the pillars 2 are provided above and below the joint 3, but there is also a case where the pillars 2 are provided only above or below the joint 3. In this embodiment, the beams 4 are provided on the left and right of the joint 3, but there is also a case where the beams 4 are provided only on the left or right of the joint 3. Furthermore, the beams 4 are not only provided in the left-right direction of the joint 3 (corresponding to the left-right direction in FIG. 1(b)), but also in some cases are provided in the front-to-back direction (corresponding to the up-to-down direction in FIG. 1(b)), which is perpendicular to the left-to-right direction in a plan view, and in this case too, a beam 4 having a similar configuration can be provided in front of or behind the joint 3, or both.

[0033] In this embodiment, the column 2 is made of reinforced concrete, which is excellent in terms of strength and fire resistance, but the column 2 is not limited to this. Below, examples in which the column 2 has a different structure will be described as the second and third embodiments. In the second and third embodiments, the configurations that are different from the first embodiment will be mainly described, and similar configurations will be given the same reference numerals in the figures and the like and will not be described again. Furthermore, the configurations described in each embodiment, including the first embodiment, can be combined as needed.

[0034] [Second embodiment] 5(a) and 5(b) are diagrams showing a joint structure 1a according to a second embodiment of the present invention, in which Fig. 5(a) is a diagram showing the joint structure 1a as seen from the front, and Fig. 5(b) is a diagram showing a horizontal cross section taken along line BB in Fig. 5(a).

[0035] The joint structure 1a of this embodiment differs from the first embodiment in that the pillar 2a is a composite structure made of exterior timber 22 and concrete 23.

[0036] The outer timbers 22 are plank-shaped wooden materials and are arranged to cover all sides of the pillars 2a. Concrete 23 is filled inside the outer timbers 22. As in the first embodiment, vertical reinforcing bars 21 are embedded inside the concrete 23, and their lower ends are inserted into the upper parts of sleeves 24 embedded in the lower ends of the concrete 23.

[0037] Glued laminated timber, CLT, BP lumber, etc. can be used for the exterior timbers 22. Like the exterior timbers 411, the exterior timbers 22 function as shear reinforcement for the columns 2a and as formwork when pouring the concrete 23, and also serve as burners that contribute to the fire resistance of the reinforced concrete inside. Furthermore, by leaving the wood exposed while maintaining the strength of the members with the concrete 23, the inherent beauty of wooden construction can be expressed.

[0038] The method for constructing the joint structure 1a is basically the same as that of the first embodiment, and the same effects as those of the first embodiment can be obtained in this embodiment. Note that, although the columns 2a are made of precast members in this embodiment, the columns 2a may be constructed on-site by arranging reinforcing bars 21 and the like, assembling outer timbers 22, pouring concrete 23, and the like at the construction site of the columns 2a.

[0039] In addition to the reinforcing bars 21, hoops for shear reinforcement can also be provided inside the concrete 23 so as to surround the reinforcing bars 21 in a plan view. Furthermore, when concrete 23 is poured inside the outer timbers 22 in a factory or the like to fabricate the columns 2a, the outer timbers 22 that are positioned opposite each other in a plan view are connected by separators (not shown) to resist the out-of-plane pressure applied to the outer timbers 22 by the concrete 23, and these separators can also be used as shear reinforcement.

[0040] Furthermore, by providing a shear stress transmission mechanism such as a connector (not shown) that protrudes from the inner surface of the outer wooden piece 22 into the concrete 23, the integrity of the outer wooden piece 22 and the concrete 23 can be improved.

[0041] As shown in the cross section in FIG. 6, the intermediate beam 42a may be a beam-shaped precast member having a composite structure of outer wood 421 and concrete 422, similar to the column 2a.

[0042] The exterior timbers 421 are planar wooden materials that are placed so as to cover both side surfaces and the bottom surface of the intermediate beam 42a, and concrete 422 is filled inside them. Holes 43 are formed in the concrete 422 to insert the protruding portions of the connecting rebars 31. Reference numeral 44 denotes a filler material such as mortar or resin that is filled into the holes 43. Glued laminated timber, CLT, BP material, etc. are used for the exterior timbers 421, and they have the same function and role as the exterior timbers 411 described above. Additionally, in this embodiment, as with the above, it is also possible for both or either the joints 3 and the end beams 41 to be made of a composite structure of exterior timber and concrete.

[0043] 6 is a precast member, the intermediate beam 42a may be constructed on-site by assembling the outer timbers 421 and pouring the concrete 422 at the construction site of the intermediate beam 42a. In this case, the protruding portions of the connecting rebars 31 and the main beam reinforcement bars (not shown) of the intermediate beam 42a may be connected by mechanical joints or the like.

[0044] [Third embodiment] 7 is a diagram showing a joint structure 1b according to a third embodiment of the present invention, as viewed from the front. The joint structure 1b of this embodiment differs from the first embodiment in that the pillars 2b are wooden members and the entire structure is made of wood materials.

[0045] The wooden material can be, but is not limited to, laminated wood. Although not shown, a flame-retardant layer is provided on all sides of the column 2b to ensure the fire resistance of the column 2b. The flame-retardant layer is made by impregnating the wooden material with a flame-retardant agent, but is not limited to this and may be made of other materials with fire resistance. In some cases, the flame-retardant layer can be omitted.

[0046] A portion of a vertical reinforcing bar 25 is embedded in the upper end of column 2b. For example, a portion of the reinforcing bar 25 is inserted into a hole (not shown) formed in the upper end of column 2b in the material axis direction, and the hole is filled with a filler material such as mortar or resin. This allows a portion of the reinforcing bar 25 to be embedded and fixed in the upper end of column 2b. The remaining portion of the reinforcing bar 25 protrudes upward from column 2b, passes vertically through a through-hole 34 in joint 3, and protrudes further upward from joint 3. A filler material 35 (see FIG. 1(b)) is filled in the through-hole 34.

[0047] On the other hand, a hole 26 for joining the column 2b is provided at the lower end of the column 2b. The protruding portion of the reinforcing bar 25 protruding from the joint 3 is inserted into the hole 26 of the column 2b above the joint 3, and the hole 26 is filled with a filler material (not shown) such as mortar or resin, thereby joining the column 2b above the joint 3 to the joint 3.

[0048] The method of constructing the joint structure 1b is also basically the same as that of the first embodiment, and when providing a column 2b above the joint 3, the column 2b is dropped in from above as shown in Fig. 8. As described above, the protruding portion of the reinforcing bar 25 protruding upward from the joint 3 is inserted into the hole 26 of the column 2b, and the hole 26 is filled with a filler, thereby joining the column 2b above the joint 3.

[0049] This embodiment also provides the same effects as the first embodiment. Furthermore, by actively using wooden materials for the columns 2b, it is possible to provide a frame that is excellent in terms of both the environment and design. In this embodiment, as in the above, it is also possible to use a composite structure of exterior wood and concrete for both or either of the joints 3 and end beams 41.

[0050] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art can conceive of various modifications or alterations within the scope of the technical ideas disclosed herein, and it is understood that these modifications also fall within the technical scope of the present invention. [Explanation of symbols]

[0051] 1, 1a, 1b: Joint structure 2, 2a, 2b: Pillar 3, 3a: Joint 4:Beam 21, 25: Reinforced concrete 22, 32, 411, 421: Outer timber 23, 33, 412, 422: Concrete 24: Sleeve 26, 43: Hole 31: Jointed rebar 34:Through hole 41, 41a: End beam 42, 42a: Intermediate beam

Claims

1. A joint structure in which a column and a beam are joined via a joint having a concrete portion, The beam has an end beam provided on a side surface of the joint and an intermediate beam continuous with the end beam, The intermediate beam is a beam-shaped member made of wood, the end beam has a concrete portion; The joint and the end beam are an integral precast member in which horizontal joint reinforcing bars are embedded so as to straddle the joint and the concrete portion of the end beam, A joint structure characterized in that the precast member and the intermediate beam are joined using the joint steel bars.

2. 2. The joint structure according to claim 1, wherein the column is a reinforced concrete member.

3. 2. The joint structure according to claim 1, wherein the pillar has a composite structure in which concrete is filled inside the outer timber.

4. 2. The joint structure according to claim 1, wherein the pillar is a wooden member.

5. 2. The joint structure according to claim 1, wherein the joint and the end beam have a composite structure in which concrete is filled inside the outer timber.

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