Column-beam joint structure and its construction method

Abstract

To provide a column-beam joint structure with a high joint strength, and its construction method, for a column-beam joint structure consisting of a concrete column and a wooden beam that are joined with a bracket.SOLUTION: A column-beam joint structure 100 comprises a concrete column 10 joined with a wooden bound beam 30 composed of a pair of wooden beams 40 parallelly aligned with a spacing 45. Fastener pins 51 protrude in from the side surfaces 43 of both the pair of wooden beams 40. A bracket 20 jutting out on the side of the column 10 is sandwiched between the pair of wooden beams 40. The bracket 20 is a cast-in-place concrete body burying the fastener pins 51 in it.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a column-beam joint structure and a construction method thereof.

Background Art

[0002] RC (Reinforced Concrete) columns, S (Steel) columns, SRC (Steel Reinforced Concrete) columns, and even wooden columns are used. Brackets made of RC or S are protruded from the sides of these columns, and a wooden beam is bolted or otherwise joined to the bracket. Then, a floor slab made of RC, wood, steel, etc. is placed on the wooden beam. This building structure may be applied in some cases. For example, in addition to columns constructed on-site, there are PCa (Precast Concrete) columns that are factory-manufactured, transported to the site, and assembled on-site. By applying the latter PCa columns, it is possible to construct a column-beam joint structure with a significantly shortened construction period and excellent quality. Also, there are various types of configurations for the columns and brackets. For example, an RC structure where the column and bracket are integrated, or a configuration where a joint with a bracket is interposed between upper and lower columns can be cited as an example. In addition, floor slabs supported by wooden beams also exist in various forms, such as PCa floor slabs and wooden floor slabs, in addition to RC floor slabs constructed on-site.

[0003] Thus, by applying a wooden beam to the beam, it is possible to reduce the load on the environment, and due to its lightweight, the handling and constructability of the beam at the site are improved, and the excellent aesthetic design property emitted by the wood is demonstrated.

[0004] Here, Patent Document 1 proposes a joining structure for structural members. This joining structure includes a first structural member having a metallic column as a first load-bearing part and a first fire-resistant coating part provided to cover the surface of the first load-bearing part, a wooden beam as a second load-bearing part, a second structural member having a second fire-resistant coating part provided to cover the surface of the second load-bearing part, and joining means for joining the first structural member and the second structural member. The joining means is joined to the metallic column at one end without passing through the first fire-resistant coating part and is joined to the wooden beam at the other end through the second fire-resistant coating part. One end of the joining plate forming the joining means is welded to the metallic column, and the metallic column and the wooden beam are joined through the joining means by bolts and nuts, which are fixing means inserted through bolt insertion through-holes in both the joining plate and the wooden beam.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the joining structure of the wooden beam described in Patent Document 1, since the column (joint part) and the wooden beam are bolt-joined by tightening bolts inserted through bolt insertion through-holes in both the joining plate and the wooden beam with nuts, there is a possibility that looseness may occur in the joining structure, and a decrease in the joining strength in the joining structure is a concern.

[0007] The present invention has been made in view of the above problems, and relates to a column-beam joining structure in which a concrete column and a wooden beam are joined via a bracket, and aims to provide a column-beam joining structure that is less likely to loosen and has high joining strength, and a construction method thereof.

Means for Solving the Problems

[0008] To achieve the above object, one aspect of the column-beam joining structure according to the present invention is A column-beam joint structure in which a concrete column is joined to a combined wooden beam formed by arranging a pair of wooden beams with a gap therebetween, fasteners project from both side surfaces of the pair of wooden beams, a bracket projecting laterally of the column is sandwiched between the pair of wooden beams, and the bracket is a cast-in-place concrete body that embeds the fasteners.

[0009] According to this aspect, since the fasteners projecting from the side surfaces of the pair of wooden beams forming the combined wooden beam are embedded in the bracket made of the cast-in-place concrete body projecting laterally of the column, rattling hardly occurs, and a column-beam joint structure with high joint strength is obtained. Here, the reinforcing bars for the bracket are fixed to the panel zone (or joint) of the column, and the cast-in-place concrete is constructed in a state where the reinforcing bars for the bracket and the fasteners projecting from the side surface of the wooden beam intersect, and the bracket made of the cast-in-place concrete body is constructed, whereby the column and the combined wooden beam are firmly joined via the bracket.

[0010] Another aspect of the column-beam joint structure according to the present invention is a column-beam joint structure in which a concrete column is joined to a wooden beam, fasteners project from the side surface of the wooden beam, the wooden beam is disposed laterally of a bracket projecting laterally of the column, and the bracket is a cast-in-place concrete body that embeds the fasteners.

[0011] According to this aspect, since the fasteners projecting from the side surface of one wooden beam are embedded in the bracket made of the cast-in-place concrete body projecting laterally of the column, rattling hardly occurs, and a column-beam joint structure with high joint strength is obtained. For example, when it is desired to dispose only one wooden beam on the outdoor side from various viewpoints such as various arrangements with respect to a column disposed on the outer periphery of a building, the column-beam joint structure of this aspect is suitable.

[0012] In addition, another aspect of the column-beam joint structure according to the present invention is that the panel zone of the column to which the bracket is joined is a cast-in-place concrete body.

[0013] According to this aspect, since the panel zone of the column and the bracket are cast-in-place concrete bodies, for example, when both are constructed by continuous concrete casting, it is not necessary to roughen the side surface of the panel zone that has already hardened prior to the concrete casting of the bracket. Therefore, the column-beam joint structure can be constructed with excellent workability.

[0014] Here, although the form in which the concrete casting of the panel zone and the bracket is continuously performed as described above is preferable, for example, the concrete casting of the panel zone is performed first, and after the concrete of the panel zone has hardened, the concrete casting of the bracket is performed. Discontinuous concrete casting is also included.

[0015] In addition, another aspect of the column-beam joint structure according to the present invention is that the panel zone of the column to which the bracket is joined and at least one of the general parts of the columns above and below it are cast-in-place concrete bodies.

[0016] According to this aspect, since the panel zone of the column, at least one of the general parts of the columns above and below it, and the bracket are cast-in-place concrete bodies, for example, when the general part of the column, the panel zone, and the bracket are constructed by continuous concrete casting, it is not necessary to roughen the joint surface of the general part of the column that has already hardened prior to the concrete casting of the panel zone, and furthermore, it is not necessary to roughen the side surface of the panel zone that has already hardened prior to the concrete casting of the bracket. Therefore, the column-beam joint structure can be constructed with excellent workability.

[0017] Here, the "general part of at least one of the columns above and below the panel zone of the column" includes the general parts of both columns above and below the panel zone and the general part of either the upper or lower column of the panel zone.

[0018] Here, although it is preferable that the concrete placement of the panel zone, the general part of the columns above and below the panel zone, and the brackets is carried out continuously as described above, for example, the concrete placement of the general part of the column is carried out first, the concrete placement of the panel zone is carried out after the concrete of the general part has hardened, and the concrete placement of the brackets is carried out after the concrete of the panel zone has hardened. Discontinuous concrete placement is also included.

[0019] Also, another aspect of the column-beam joint structure according to the present invention is characterized in that the fastener is any one of a drift pin, a lag screw bolt, a wood screw, a nail, a bolt, and a glue-in rod.

[0020] According to this aspect, various forms such as lag screw bolts and drift pins are applied as fasteners, and any of them can join the wooden beam and the bracket with high strength. Here, the glue-in rod (GIR: Glue in rod) can also be referred to as the glued-in rod (GIR: Glued in rod). It is a construction method (method) of opening holes in wooden members, inserting steel bars into the holes, filling the holes with resin adhesive, and joining the members together. The fastener includes the combination of this resin adhesive and the steel bar.

[0021] Also, one aspect of the construction method of the column-beam joint structure according to the present invention is a construction method of the column-beam joint structure for constructing the column-beam joint structure by joining a concrete column and a combined wooden beam in which a pair of wooden beams are provided with a gap therebetween, projecting reinforcing bars for brackets from the side surface of the column, projecting fasteners from the side surfaces of both of the pair of wooden beams, crossing the fasteners with the reinforcing bars, and arranging the pair of wooden beams so as to sandwich the reinforcing bars, While causing the pair of wooden beams to function as a formwork, a separate formwork is assembled at a necessary location including below the reinforcing bars, and concrete is placed inside the formwork to construct a bracket which is a cast-in-place concrete body, and the formwork is removed to construct the column-beam joint structure.

[0022] According to this aspect, a fixture projecting from the side surfaces of a pair of wooden beams forming a combined wooden beam is made to intersect with a reinforcing bar for a bracket projecting from the side surface of a column, and the pair of wooden beams are arranged so as to sandwich the reinforcing bar. While causing the pair of wooden beams to function as a formwork, a separate formwork is assembled at a necessary location including below the reinforcing bars, and concrete is placed inside the formwork to construct a bracket. Since the pair of wooden beams do not need to be removed from the formwork, the work efficiency of both assembling and removing the formwork is increased, and a column-beam joint structure with high joint strength can be constructed with excellent constructability. Here, "assembling a separate formwork at a necessary location including below the reinforcing bars" means, for example, assembling a formwork for the side where there are no columns (panel zones) or a pair of wooden beams among the lower side and the side of the reinforcing bar.

[0023] Another aspect of the method for constructing a column-beam joint structure according to the present invention is a method for constructing a column-beam joint structure in which a concrete column and a wooden beam are joined to construct the column-beam joint structure, projecting a reinforcing bar for a bracket from the side surface of the column, projecting a fixture from the side surface of the wooden beam, intersecting the fixture with the reinforcing bar, and arranging the wooden beam on the side of the reinforcing bar, While causing the wooden beam to function as a formwork, a separate formwork is assembled at a necessary location including below the reinforcing bars, and concrete is placed inside the formwork to construct a bracket which is a cast-in-place concrete body, and the formwork is removed to construct the column-beam joint structure.

[0024] According to this aspect, a fixture projecting from one side surface of one wooden beam is crossed with a reinforcing bar for a racket projecting from the side surface of a column, and the one wooden beam is disposed laterally of the reinforcing bar. While making the one wooden beam function as a formwork, a separate formwork is assembled at a necessary location including below the reinforcing bar, and concrete is placed inside the formwork to construct a bracket. Since the wooden beam does not need to be demolded, the work efficiency of both assembling and demolding the formwork is increased, and a column-beam joint structure with high joint strength can be constructed with excellent constructability.

[0025] Also, another aspect of the method for constructing a column-beam joint structure according to the present invention is A formwork is also installed around the panel zone of the column to which the bracket is joined, and concrete is placed inside the formwork to construct the panel zone, which is a cast-in-place concrete body, and the bracket, and the formwork is demolded to construct the column-beam joint structure.

[0026] According to this aspect, the panel zone of the column and the bracket are cast-in-place concrete bodies. For example, by constructing both by continuous concrete placement, it is not necessary to roughen the side surface of the panel zone that has already hardened prior to the concrete placement of the bracket. Therefore, a column-beam joint structure can be constructed with excellent constructability.

[0027] Also, another aspect of the method for constructing a column-beam joint structure according to the present invention is A formwork is also installed around the panel zone of the column to which the bracket is joined and around at least one of the upper and lower general parts of the column, and concrete is placed inside the formwork to construct the panel zone, the bracket, and the general part of the column, which are cast-in-place concrete bodies, and the formwork is demolded to construct the column-beam joint structure.

[0028] According to this aspect, the panel zone of the column, at least one general part of the columns above and below it, and the brackets are in-situ cast concrete bodies. For example, by constructing these through continuous concrete casting, there is no need to roughen the joint surface of the general part of the column that has already hardened prior to the concrete casting of the panel zone. Furthermore, since there is no need to roughen the side surface of the panel zone that has already hardened prior to the concrete casting of the brackets, the column-beam joint structure can be constructed with excellent workability.

Advantages of the Invention

[0029] As can be understood from the above description, according to the column-beam joint structure and its construction method of the present invention, regarding a column-beam joint structure in which a concrete column and a wooden beam are joined via brackets, rattling is less likely to occur, and a column-beam joint structure with high joint strength and its construction method can be provided.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0031] Hereinafter, an example of the column-beam joint structure according to the embodiment will be described with reference to the accompanying drawings. In this specification and the drawings, for substantially the same components, the same reference numerals may be used to omit redundant descriptions.

[0032] [Column-Beam Joint Structure and Its Construction Method According to the Embodiment] With reference to FIGS. 1 to 4, an example of the column-beam joint structure and its construction method according to the embodiment will be described. Here, FIGS. 1, 3, and 4 are process diagrams for explaining an example of the construction method of the column-beam joint structure according to the embodiment in order, and FIG. 4 is a perspective view showing an example of the column-beam joint structure according to the embodiment. Further, FIG. 2 is a view corresponding to FIG. 1 and shows another example of the fixture projecting from the side surface of the wooden beam. Hereinafter, in each figure, the illustration of the main reinforcement bars, stirrups, etc. of the column 10 is omitted.

[0033] In the following description, a method of joining the matching wooden beam 30 to the column 10 via the bracket 20 by constructing the bracket 20 on-site on one side surface 11 of the column 10 will be described, but this construction method may be applied to forms other than the illustrated example.

[0034] For example, in addition to the bracket 20, the panel zone to which the bracket 20 is joined may be continuously constructed on-site, or in addition to the bracket 20, the panel zone to which the bracket 20 is joined and the general parts of the upper and lower columns 10 to which the panel zone is joined may be continuously constructed on-site.

[0035] Also, instead of the matching wooden beam 30, one wooden beam 40 may be joined to the bracket 20 on-site.

[0036] Furthermore, the construction method in the illustrated example describes the method of constructing the bracket 20 on-site on one side surface 11 of the column 10, but the bracket 20 may be similarly constructed on the other side surfaces 11 of the column 10, and the matching wooden beam 30 may be joined via the bracket 20.

[0037] As shown in Fig. 1, reinforcing bars 25 for brackets 20 indicated by dotted lines for on-site construction project protrude from the side surface 11 of a reinforced concrete column 10. This column 10 is, for example, a PCa column manufactured at a factory. When manufacturing the PCa column 10, a part (fixing portion) of the reinforcing bar 25 is disposed inside the reinforcing bars (main reinforcing bars and stirrups) for the column (panel zone), and concrete for the column is placed. Thus, as shown in Fig. 1, the PCa column 10 with the reinforcing bar 25 protruding laterally from the side surface 11 is manufactured. Incidentally, when both the panel zone and the bracket are constructed on-site as described above, the formwork for the bracket and the formwork for the panel zone are assembled on-site, and for example, concrete is continuously placed against both formworks, so that both the panel zone and the bracket are constructed simultaneously.

[0038] Among both end portions 44 of a pair of wooden beams 40, pin holes 46 penetrating in the thickness direction of the wooden beam 40 across the left and right side surfaces 43 are provided at a plurality of corresponding positions. By driving the end portions of drift pins 51 (an example of a fastener) into each pin hole 46 of one wooden beam 40, a state is formed in which a plurality of drift pins 51 protrude from the side surface 43.

[0039] Then, one wooden beam 40 is disposed laterally of the reinforcing bar 25 so that each drift pin 51 intersects the reinforcing bar 25 for the bracket. By driving the end portions of the corresponding drift pins 51 into each pin hole 46 of the other wooden beam 40, a pair of wooden beams 40 are disposed on the left and right sides of the reinforcing bar 25 for the bracket, and a state is formed in which a plurality of drift pins 51 connecting both (in other words, protruding from both sides) intersect the reinforcing bar 25.

[0040] Here, the wooden beam 40 forming the combined wooden beam 30 is formed by laminating a large number of veneer boards in a manner such that the fiber directions are alternately orthogonal and bonding them to each other. Here, in addition to the laminate of veneer boards, the wooden beam 40 may also be a cross-laminated timber (CLT) or a laminated veneer lumber (LVL).

[0041] In the building structure, with respect to the reinforcing bars 25 for brackets of each of a pair of columns 10 erected with a predetermined span, both ends of the laminated wooden beam 30 suspended by, for example, a crane or the like are positioned, and the pair of wooden beams 40 are supported from below by shoring as necessary.

[0042] Here, instead of the drift pins 51 shown in FIG. 1, as shown in FIG. 2, by screwing the tips of a plurality of lag screw bolts 53 (another example of a fastener) into the pilot holes provided in the side surface 43 of the wooden beam 40, a state is created in which the plurality of lag screw bolts 53 protrude from the side surface 43, and the pair of wooden beams 40 provided with the plurality of lag screw bolts 53 on both sides may be arranged so as to intersect the reinforcing bars 25.

[0043] Next, as shown in FIG. 3, the end portions 44 of the pair of wooden beams 40 arranged on the left and right side surfaces of the reinforcing bar 25 are made to function as formwork, a separate formwork K for closing the front surface of the bracket is assembled in the gap 45 between the pair of wooden beams 40, and a separate formwork (not shown) is also assembled below the reinforcing bar 25.

[0044] Next, as shown in FIG. 4, concrete is placed in the space surrounded by the end portions 44 of the pair of wooden beams 40 functioning as formwork and the other formwork K, and after waiting for the concrete to harden, the formwork K is removed, whereby the bracket 20 joined to the column 10 via the reinforcing bar 25 is constructed, and a column-beam joint structure 100 in which the pair of wooden beams 40 are joined to the bracket 20 by a plurality of drift pins 51 embedded inside the bracket 20 is constructed.

[0045] More specifically, for a pair of columns 10 forming the building structure, the brackets 20 are constructed on-site simultaneously or sequentially, and a column-beam joint structure 100 is constructed in which both end portions of the laminated wooden beam 30 and the corresponding columns 10 are joined via the respective brackets 20.

[0046] In the example shown in FIG. 4, the lower surfaces 41 of each of the pair of wooden beams 40 and the lower surface 21 of the bracket 20 are flush with each other. Similarly, the upper surfaces 42 of each of the pair of wooden beams 40 and the upper surface 22 of the bracket 20 are also flush with each other.

[0047] Since the upper surfaces 42 of each of the pair of wooden beams 40 and the upper surface 22 of the bracket 20 are flush with each other, a floor slab (not shown) can be placed flat and stably. This floor slab includes various forms such as a PCa floor slab (a floor slab made of PCa reinforced concrete, a PC prestressed concrete floor slab (PC floor slab)), a half-PCa floor slab and a PC composite floor slab of a site-constructed floor slab, an ALC (Autoclaved Lightweight aerated Concrete) panel, a CLT panel, a site-constructed floor slab (concrete floor slab), etc.

[0048] Also, since the lower surfaces 41 of each of the pair of wooden beams 40 and the lower surface 21 of the bracket 20 are flush with each other, a ceiling board (not shown) can be installed flat and stably on the lower surface 41 of the end portion 44 of the combined wooden beam 30 and the lower surface 21 of the bracket 20 therebetween.

[0049] According to the construction method of the illustrated example, the pair of wooden beams 40 can function as a formwork when constructing the bracket 20. Since the pair of wooden beams 40 do not require form removal, the assembly and form removal of a part of the formwork can be omitted, and the on-site constructability of the bracket 20 is improved.

[0050] Also, according to the column-beam joint structure 100 of the illustrated example, the fasteners 51 protruding from both side surfaces 43 of the pair of wooden beams 40 forming the combined wooden beam 30 are embedded in the bracket 20 made of a cast-in-place concrete body protruding laterally from the column 10, resulting in a column-beam joint structure with high joint strength.

[0051] Other embodiments may be possible in which other components are combined with the configurations and the like described in the above embodiments, and the present invention is not limited to the configurations shown here. In this regard, it is possible to make changes without departing from the spirit of the present invention, and it can be appropriately determined according to the application form.

Explanation of Signs

[0052] 10: Column (PCa column) 11: Side surface 20: Bracket 21: Bottom surface 22: Top surface 25: Reinforcing bar for bracket (reinforcing bar) 30: Laminated wood beam 40: Wood beam 41: Bottom surface 42: Top surface 43: Side surface 44: End 45: Gap 46: Pin hole 51: Fastener (drift pin) 53: Fastener (lag screw bolt) 100: Column-beam joint structure K: Formwork

Claims

1. A column-beam joint structure in which a concrete column is joined to a combined wooden beam formed by juxtaposing a pair of wooden beams with a gap therebetween, fasteners project from both side surfaces of the pair of wooden beams, a bracket projecting to the side of the column is sandwiched between the pair of wooden beams, and the bracket is a cast-in-place concrete body for embedding the fasteners. The column-beam joint structure is characterized by this.

2. A column-beam joint structure in which a concrete column is joined to a wooden beam, fasteners project from the side surface of the wooden beam, the wooden beam is disposed on the side of a bracket projecting to the side of the column, and the bracket is a cast-in-place concrete body for embedding the fasteners. The column-beam joint structure is characterized by this.

3. The column-beam joint structure according to claim 1 or 2, wherein a panel zone of the column to which the bracket is joined is a cast-in-place concrete body.

4. The column-beam joint structure according to claim 1 or 2, wherein a panel zone of the column to which the bracket is joined and at least one general part of the column above or below it are cast-in-place concrete bodies.

5. The column-beam joint structure according to claim 1 or 2, wherein the fastener is any one of a drift pin, a lag screw bolt, a wood screw, a nail, a bolt, and a glue-in rod.

6. A construction method of a column-beam joint structure for joining a concrete column to a combined wooden beam formed by juxtaposing a pair of wooden beams with a gap therebetween to construct a column-beam joint structure, projecting reinforcing bars for brackets from the side surface of the column, projecting fasteners from both side surfaces of the pair of wooden beams, crossing the fasteners with the reinforcing bars, and disposing the pair of wooden beams so as to sandwich the reinforcing bars, while making the pair of wooden beams function as a formwork, assembling a separate formwork at a necessary location including below the reinforcing bars, casting concrete inside the formwork, thereby constructing a bracket that is a cast-in-place concrete body, and demolding the formwork to construct the column-beam joint structure. The construction method of the column-beam joint structure is characterized by this.

7. A construction method of a column-beam joint structure for joining a concrete column to a wooden beam to construct a column-beam joint structure, projecting reinforcing bars for brackets from the side surface of the column, projecting fasteners from the side surface of the wooden beam, crossing the fasteners with the reinforcing bars, and disposing the wooden beam on the side of the reinforcing bars, While making the wooden beam function as a formwork, separately assemble a formwork at necessary locations including below the reinforcing bars, and place concrete inside the formwork to construct a bracket which is a cast-in-place concrete body, and demold the formwork to construct the column-beam joint structure. A construction method of a column-beam joint structure, characterized by this.

8. Also install a formwork around the panel zone of the column to which the bracket is joined, and place concrete inside the formwork to construct a panel zone and a bracket which are cast-in-place concrete bodies, and demold the formwork to construct the column-beam joint structure. A construction method of a column-beam joint structure according to claim 6 or 7, characterized by this.

9. Also install a formwork around the panel zone of the column to which the bracket is joined and around at least one of the general parts of the column above and below it, and place concrete inside the formwork to construct a panel zone, a bracket, and the general part of the column which are cast-in-place concrete bodies, and demold the formwork to construct the column-beam joint structure. A construction method of a column-beam joint structure according to claim 6 or 7, characterized by this.

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