Structure joints

Abstract

To provide a joint structure of a structure allowing heat transmission from a steel structural member to a wooden structural member to be suppressed.SOLUTION: A joint structure 10 of a structure joints a steel column 11 of a first steel structural member and a wooden beam 12 of a second wooden structural member through a gusset plate 13 fixed on the steel column 11, wherein the gusset plate 13 is provided with an extended portion 13b extending above the wooden beam 12, and a heat transmission steel bar 17 as a protruded member protruding in a direction perpendicular to a surface of the gusset plate 13 buried in a concrete of a floor slab 18 installed on an upper portion of the wooden beam 12 is attached on the extended portion 13b to transmit heat of the steel column 11 from the extended portion 13b of the gusset plate 13 to the concrete of the floor slab 18 through the heat transmission steel bar 17.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a joining structure for structural members in which a steel structural member and a wooden structural member are joined via a gusset plate. [Background technology]

[0002] Generally, when joining a column with a wooden core to a steel beam, the base plate of the gusset plate is positioned so that it comes into contact with the core, and this base plate is then fixed with an anchor bolt, after which the gusset plate is pin-joined to the beam. However, in the event of a fire, the heat from the beams would be transferred through the steel gusset plates to the wooden core, raising the temperature of the core above its combustion initiation temperature and causing it to burn. Therefore, a technology has been disclosed in which a gusset plate is fixed to the core material via a concrete block to suppress the transfer of heat from the steel beam to the core material. The concrete block is a rectangular precast member made of reinforced concrete, and the end of the concrete block is inserted into a notch formed in the side of the column on the beam side, and fixed to the column with an anchor bolt (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5990424 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above Patent Document 1, since the concrete blocks are heavy, a large load acts on the joints of the columns, which not only increases the risk of reducing the strength of the columns, but also requires that the base plate be embedded within the concrete block, making it not necessarily practical as a fire-resistant structure.

[0005] The present invention has been made in consideration of the problems in the conventional art, and aims to provide a joining structure for a structure that can suppress the transfer of heat from a steel structural member to a wooden structural member. [Means for solving the problem]

[0006] The present invention relates to a joint structure for a structure in which a first structural member made of steel and a second structural member made of wood are joined via a gusset plate fixed to the first structural member, the first structural member being a column or beam, the second structural member being a beam, the gusset plate having an extension extending above the second structural member, and a protruding member protruding in a direction perpendicular to the surface of the gusset plate is attached to the extension and embedded in the concrete of a floor slab poured on top of the beam, which is the second structural member. Anyway This allows the heat from the first structural member to be dissipated through the protruding member to the concrete, which has a large heat capacity, thereby suppressing the impact of heat on the second structural member, which is made of wood. In addition, it is characterized by the following features: That is By connecting the protruding members to the reinforcement embedded in the concrete of the floor slab or to a deck plate laid underneath the concrete of the floor slab, heat can be dissipated into the concrete from the reinforcement or floor panel, thereby effectively suppressing the effects of heat on the second structural member. or, By forming a plurality of holes in the extension portion arranged along the extension direction of the second structural member, and inserting and contacting steel bars or round steel bars as protruding members into each of these holes, it is possible to dissipate heat from the first structural member to the concrete with a simple configuration. Alternatively, the upper end of the extension portion is provided with a second structural member in the extension direction. To Along Distribute Alternatively, a plurality of recesses may be formed in which reinforcing bars or round steel bars are placed, and each of the recesses may be in contact with a reinforcing bar or round steel bars. orThe upper end of the extension portion may be structured as a base plate extending in the extension direction of the gusset plate, with the plate surface direction perpendicular to the extension direction of the protruding portion, and the upper surface of the base plate may be in contact with a steel bar or round steel bar serving as the protruding member. Also, the same effect can be obtained if the protruding member is a plate protruding from the extension portion. do. N Needless to say, the protruding members should be made of materials with excellent thermal conductivity, such as reinforcing bars or steel plates. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing a joint structure of a structure according to an embodiment of the present invention; [Diagram 2] 13A and 13B are diagrams illustrating other examples of the protruding member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] 1(a) to (c) are diagrams showing a joint structure 10 for a structure according to the present embodiment, where (a) is a vertical cross-sectional view, (b) is a horizontal cross-sectional view, and (c) is a perspective view of a main portion. In each figure, 11 is a steel column as the first structural member, 12 is a wooden beam as the second structural member, 13 is a gusset plate, 14 is a fire-resistant coating layer for the column, 15 is a fire-resistant coating layer for the wooden beam, 16 is a drift pin, 17 is a heat-transfer steel bar as a protruding member, and 18 is a floor slab, and in this example, the floor slab 18 is made of reinforced concrete. Hereinafter, the vertical direction in Fig. 1(a), which is the extension direction of the steel column 11, will be referred to as the vertical direction, the left-right direction in Fig. 1(a), which is the extension direction of the wooden beam 12, will be referred to as the front-rear direction, and the vertical direction in Fig. 1(b), which is the width direction of the beam 12, will be referred to as the left-right direction. In addition, the side of the wooden beam 12 that faces the steel column 11 will be referred to as the front side. The steel column 11 is a cylindrical member made of a steel pipe with a rectangular cross section, and a gusset plate 13 is attached by welding or the like to the surface side of the side surface 11a on the wooden beam 12 side. Note that the steel column 11 may also be made of an H-shaped steel or the like. The wooden beam 12 is made of wood having a rectangular cross section, and has a slit 12a and a plurality of drift pin insertion holes 12b formed on the side facing the steel column 11. The slit 12a is a rectangular groove in plan view that extends in the front-rear direction from the center of the width of the wooden beam 12 and opens toward the steel column 11, and its depth is smaller than the thickness (length in the up-down direction) of the wooden beam 12. A gusset plate 13 is inserted into the slit 12a. The drift pin insertion hole 12b is a through hole that extends in the left-right direction, and a drift pin 16 (described later) is driven into the drift pin insertion hole 12b. The wooden beam 12 is joined to the steel column 11 by a pin joint between the gusset plate 13 inserted into the slit 12a and a drift pin 16. The method of joining the wooden beam 12 and the steel column 11 with the gusset plate 13 is not limited to the drift pin 16, and may be, for example, a bolt and nut. In short, any joining method that penetrates the gusset plate 13 will do.

[0009] The gusset plate 13 is a plate-like member made of steel plate with a plate surface perpendicular to the left-right direction, and includes a rectangular joint 13a housed in the slit 12a, and an extension 13b extending upward from the joint 13a. In this example, the extension 13b is shaped to be an upward extension of the joint 13a. In other words, the protruding length (length in the front-rear direction) of the extension 13b is the same as the protruding length of the joint 13a. In this example, the height of the extension 13b is about 70% of the thickness dimension of the floor slab 18, but the upper end of the extension 13b may be extended to near the top surface of the floor slab 18. The joint portion 13a is formed with a plurality of pin holes 13c for passing the drift pins 16 therethrough, and the extension portion 13b is formed with fixing holes 13d for inserting and fixing the heat transfer reinforcing bars 17 therein. The column fireproof coating layer 14 is a fireproof layer provided so as to surround the steel column 11, and is formed, for example, by spraying rock wool, which is a fireproof material. Note that well-known fireproof materials such as calcium silicate and ALC board may also be used. The fire-resistant coating layer 15 for the wooden beam is a fire-resistant layer provided on the underside and the left and right sides of the wooden beam 12, and is made of a fire-resistant material such as gypsum board. It is constructed from fire-resistant materials such as gypsum board. The drift pin 16 is a rod-shaped member with a tip diameter smaller than the diameter of the drift pin insertion hole 12b, and is driven into the drift pin insertion hole 12b of the wooden beam 12 to pin-join the gusset plate 13 and the wooden beam 12. The heat transfer rebar 17 is a steel rod-shaped member having a circular cross section, which is inserted and fixed into the fixing hole 13d formed in the extension portion 13b of the gusset plate 13 so that the extension direction is parallel to the left-right direction, and is embedded in the concrete of the floor slab 18 after the floor slab 18 is poured. In this example, both ends and a middle portion of the heat transfer rebar 17 are attached to the rebar (hereinafter referred to as the longitudinal rebar 18a) that extends in the front-rear direction, which is the length direction of the wooden beam 12, among the rebars 18a, 18b of the floor slab 18. The heat transfer rebar 17 may be made of the same material as the rebars 18a, 18b of the floor slab 18, for example. After the joining of the steel columns 11 and the wooden beams 12 is completed, the floor slab 18 is poured on a horizontal plane including the upper surface of the wooden beams 12. Specifically, after spacers 18s are placed on the upper surface of the wooden beams 12, reinforcing bars (hereinafter referred to as widthwise reinforcing bars 18b) extending in the left-right direction, which is the width direction of the wooden beams 12, are attached to the spacers 18s, and the above-mentioned lengthwise reinforcing bars 18a are further attached to the widthwise reinforcing bars 18b. After that, a formwork (not shown) is constructed, and concrete is poured into the formwork to construct the floor slab 18. Alternatively, a deck plate may be used, and after the spacers 18s are placed on the deck plate, reinforcing bars assembled in a mesh shape (wire mesh) may be placed on the deck plate. In this case, the heat transfer reinforcing bars 17 may be attached to the wire mesh or may be attached to the deck plate via wires or the like.

[0010] Next, a method for constructing the joint structure 10 according to the present invention and a method for attaching the heat transfer reinforcing bar 17 will be described. First, a gusset plate 13 is attached by welding or the like to the surface side of the side surface 11a of the steel column 11 on the side of the wooden beam 12. Then, rock wool is sprayed onto the outer periphery of the steel column 11 to form a fireproof coating layer 14 for the column. Then, after the joint 13a of the gusset plate 13 is accommodated in the slit 12a of the wooden beam 12 having the fire-resistant coating layer 15 for the wooden beam formed on the bottom surface and both side surfaces, the drift pin 16 is driven into the drift pin insertion hole 12b provided in the wooden beam 12 to pin-join the steel column 11 and the wooden beam 12. The fire-resistant coating layer 14 for the column and the fire-resistant coating layer 15 for the wooden beam may be provided after the steel column 11 and the wooden beam 12 are joined. After joining the steel column 11 and the wooden beam 12, the heat transfer rebar 17 is inserted into the fixing hole 13d of the extension 13b of the gusset plate 13 and fixed by welding, wire, wire, etc., and both ends and the middle part of the heat transfer rebar 17 are attached to the longitudinal rebar 18a of the floor slab 18. Note that the heat transfer rebar 17 does not necessarily have to be fixed to the fixing hole 13d, and as long as it is in contact with the fixing hole 13d, heat from the gusset plate 13 can be transferred to the rebars 18a, 18b of the floor slab 18. Finally, a formwork is set up and concrete is poured into the formwork to construct a floor slab 18 made of reinforced concrete.

[0011] In the joint structure 10 of the present invention, as described above, both ends and the middle part of the heat-transfer reinforcing bar 17 are attached to the reinforcing bars (here, the longitudinal reinforcing bars 18a) of the floor slab 18. This allows the heat of the steel column 11, which was conventionally transferred to the wooden beam 12 through the joint 13a of the gusset plate 13 as a thermal bridge, to be transferred from the extension 13b of the gusset plate 13 through the heat-transfer reinforcing bar 17 to the concrete of the floor slab 18 and dissipated. It also allows the heat to be transferred to the reinforcing bars (the longitudinal reinforcing bars 18a and the transverse reinforcing bars 18b) of the floor slab 18 and diffused, so that the temperature rise of the wooden beam 12 can be effectively suppressed. It is preferable that the heat transfer steel bars 17 are attached to the reinforcement at multiple locations. Furthermore, although there is no particular restriction on the length of the heat transfer steel bars 17 for welding or the like, it is preferable from the standpoint of fire resistance that they be longer than the width of the wooden beams 12 .

[0012] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0013] For example, in the above embodiment, the first structural member is a steel column 11 and the second structural member is a wooden beam 12, but the present invention is also applicable to cases where the first structural member is a steel beam. In addition, in the above embodiment, the heat transfer steel bars 17 are attached to the longitudinal steel bars 18a of the floor slab 18, but simply burying them in the concrete of the floor slab 18 can also suppress the temperature rise of the wooden beams 12. In the above embodiment, the fixing holes 13d are provided in the extensions 13b of the gusset plate 13, and the heat transfer rebars 17 are inserted and fixed in the fixing holes 13d, but as shown in Fig. 2(a), a recess 19a may be provided at the upper end of the extensions 13b, and the heat transfer rebars 17 may be placed in the recesses 19a and fixed by welding, wire, etc. Note that the heat transfer rebars 17 do not necessarily need to be fixed in the recesses 19a, and may be in contact with the recesses 19a. Alternatively, as shown in Fig. 2(b), a flat base plate 19b with a vertical surface may be attached to the upper end of the extension 13b of the gusset plate 13, and the heat transfer reinforcing bar 17 may be fixed to the upper surface of the base plate 19b by welding or the like. The heat transfer reinforcing bar 17 may be attached to the extension 13b of the gusset plate 13 using a fastening member such as a bolt. Alternatively, as shown in Fig. 2(c), a T-shaped gusset plate 13T may be fabricated by integrating the extension 13b with a base plate 19b, and the heat transfer reinforcing bar 17 may be fixed to the upper surface of the base plate 19b of the gusset plate 13T by welding or the like. 2(d) and (e), instead of the heat transfer steel bars 17, a steel plate 19c or a steel plate 19d protruding in the left-right direction from the side surface of the extension portion 13b of the gusset plate 13 may be attached to transfer the heat from the steel column 11 transferred to the gusset plate 13 to the floor slab 18. The steel plate 19c is an steel plate whose plate surface faces in the up-down direction, and the steel plate 19d is an steel plate whose plate surface faces in the front-back direction. The steel plate 19c or the steel plate 19d may be protruding from the upper end of the extension portion 13b. Moreover, similarly to the above-described embodiment, if the heat transfer steel bars 17, the steel plates 19c, and the steel plates 19d are attached to the reinforcement of the floor slab 18, the temperature rise of the wooden beams 12 can be further suppressed. The material of the protruding members such as the heat transfer reinforcing bar 17, the iron plates 19c, and the iron plates 19d is not limited to iron, and any material having excellent thermal conductivity such as steel may be used. [Explanation of symbols]

[0014] 10 joint structure of structure, 11 steel column, 11a wooden beam side, 12 wooden beam, 12a slit, 12b drift pin insertion hole, 13 gusset plate, 13a joint, 13b extension, 13c pin hole, 13d fixing hole, 14 Fireproof coating layer for columns, 15 Fireproof coating layer for wooden beams, 16 Drift pin, 17 Heat transfer reinforcing bar, 18 Floor slab, 18a Length direction reinforcing bar, 18b Width direction reinforcing bar, 18s spacer.

Claims

1. A joint structure for a structure in which a first structural member made of steel and a second structural member made of wood are joined via a gusset plate fixed to the first structural member, The first structural member is a column or a beam, and the second structural member is a beam; the gusset plate includes an extension extending above the second structural member; A protruding member is attached to the extension portion and protrudes in a direction perpendicular to the surface of the gusset plate. The protruding member is embedded in concrete of a floor slab poured on the top of the beam, which is the second structural member. A joint structure of a structure, characterized in that the protruding member is connected to reinforcement embedded in the concrete of the floor slab, or to a deck plate laid underneath the concrete of the floor slab.

2. A joining structure for a structure in which a first structural member made of steel and a second structural member made of wood are joined via a gusset plate fixed to the first structural member, The first structural member is a column or a beam, and the second structural member is a beam; the gusset plate includes an extension extending above the second structural member; A protruding member is attached to the extension portion and protrudes in a direction perpendicular to the surface of the gusset plate. The protruding member is embedded in concrete of a floor slab poured on the top of the beam, which is the second structural member. The extension portion is formed with a plurality of holes arranged along an extension direction of the second structural member, A joint structure for a structure, characterized in that a reinforcing bar or a round steel bar serving as the protruding member is inserted into and contacts the hole portion.

3. A joining structure for a structure in which a first structural member made of steel and a second structural member made of wood are joined via a gusset plate fixed to the first structural member, The first structural member is a column or a beam, and the second structural member is a beam; the gusset plate includes an extension extending above the second structural member; A protruding member is attached to the extension portion and protrudes in a direction perpendicular to the surface of the gusset plate. The protruding member is embedded in concrete of a floor slab poured on the top of the beam, which is the second structural member. A plurality of recesses are formed in the upper end of the extension portion along the extension direction of the second structural member, A joint structure for a structure, characterized in that the recesses are in contact with reinforcing bars or round steel bars as the protruding members.

4. A joining structure for a structure in which a first structural member made of steel and a second structural member made of wood are joined via a gusset plate fixed to the first structural member, The first structural member is a column or a beam, and the second structural member is a beam; the gusset plate includes an extension extending above the second structural member; A protruding member is attached to the extension portion and protrudes in a direction perpendicular to the surface of the gusset plate. The protruding member is embedded in concrete of a floor slab poured on the top of the beam, which is the second structural member. A base plate is provided at an upper end of the extension portion, the base plate extending in the extension direction of the gusset plate and having a plate surface direction perpendicular to the extension direction of the extension portion, A joint structure for a structure, characterized in that the upper surface of the base plate is in contact with a reinforcing bar or round steel bar as the protruding member.

5. 5. The joint structure for a structure according to claim 1, wherein the protruding member is a plate protruding from the extension portion.

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