JP7352478B2 - Girder-to-beam connection fittings, girder-to-girder connection structures, and unit buildings - Google Patents

Description

The present invention relates to a girder-to-girder connection fitting used between girders of adjacent building units in which columns and girders are omitted, which constitute a frame body with columns and girders, a girder-to-girder connection structure, and a unit building.

Conventionally, a girder-to-girder connection structure used between girders of adjacent building units is known (for example, see Patent Document 1).

Patent Document 1 discloses a configuration in which a web of a joint piece of a building unit with a column omitted, a web of a ceiling beam of a building unit with a column omitted, and a reinforcing beam are friction-bonded using high-strength bolts. Further, Patent Document 1 discloses a configuration in which a horizontal brace mounting member having a brace fixing plate for mounting a horizontal brace is attached to a single column with bolts.

Japanese Patent Application Publication No. 9-317018

However, the invention described in Patent Document 1 requires brace fixing plates and bolts of different sizes depending on the diameter of the single column, and there is a problem that parts cannot be standardized.

Therefore, an object of the present invention is to provide a girder-to-girder connection fitting, a girder-to-girder connection structure, and a unit building that can use common parts regardless of the diameter of the columns.

In order to achieve the above object, the girder-to-girder connecting fitting of the present invention is an inter-girder-to-girder connecting fitting used between girders omitting the columns of adjacent building units, which constitute a frame body with columns and girders. a first member provided in each of the adjacent building units; and a second member supporting a horizontal brace attached to each of the first members, the first member being connected to the first piece. , a second piece perpendicular to the first piece, and the second member has an L-shaped cross section, and the second member includes a main body to which the horizontal brace is attached, and a base supporting the main body, The base includes a first base and a second base perpendicular to the first base, and has an L-shaped cross section. The feature is that a hole is formed to integrate the

Here, in the girder-to-girder connection fitting of the present invention, the main body portion may be formed to extend in the horizontal direction from the corner of the base portion.

Further, in the girder-to-beam connection fitting of the present invention, the first member may include an end plate provided at an end in the vertical direction.

Further, in the girder-to-beam connection fitting of the present invention, the hole is formed at the same position with the protruding corner of the base of the second member in contact with the inlet corner of the first member, and The second member may be attached to the first member by inserting a bolt into the hole.

Further, in the girder-to-girder connection fitting of the present invention, the first piece may be thicker than the second piece.

Further, in the girder-to-girder connection structure using the girder-to-girder connection fitting of the present invention, the first members of the two adjacent building units are arranged with their protruding corners facing each other, and one of the first members is arranged in the hole. Bolts may be inserted and tightened together.

Further, in the girder-to-girder connection structure of the present invention, the first members of the four adjacent building units are arranged with the protruding corner portions facing each other, and are placed on both sides with reinforcing plates for reinforcing the girders. Two said first members may be arranged.

Furthermore, the unit building of the present invention may have the above-mentioned girder-to-beam connection structure.

The girder-to-girder connection fitting of the present invention configured as described above includes a first member provided in each of the adjacent building units, and a second member that supports the horizontal brace and is attached to each first member. , the first member is formed into an L-shaped cross section by a first piece and a second piece perpendicular to the first piece, and the second member includes a main body to which the horizontal brace is attached and supports the main body. The base includes a first base and a second base that is orthogonal to the first base and has an L-shaped cross section, and the first member and the second member have a first base and a second base that is perpendicular to the first base. A hole is formed to integrate the Therefore, regardless of the diameter of the first member, the second member can be attached to the first member by bringing the projecting corner of the second member into contact with the entering corner of the first member. As a result, the second member can be shared and attached to the first member without being affected by the diameter of the first member.

In addition, since the main body is formed to extend horizontally from the entry corner of the base, the exit corner of the second member can be extended from the entry corner of the first member regardless of the diameter of the first member. The second member can be attached to the first member by abutting the second member. As a result, the second member can be shared and attached to the first member without being affected by the diameter of the first member.

Moreover, the first member can improve the rigidity of the first member by including end plates provided at the ends in the vertical direction. Therefore, the rigidity of the connecting fitting between the girders can be improved.

Further, the hole is formed at the same position with the protruding corner of the base of the second member in contact with the inlet corner of the first member, and a bolt is inserted into the hole so that the second member is connected to the first member. By being attached to the member, the bolt can be inserted into the holes formed in the first member and the second member, respectively, with the second member positioned on the first member. Therefore, the second member can be easily attached to the first member.

Further, by making the first piece thicker than the second piece, the strength of the first piece can be made stronger than the strength of the second piece, and the degree of freedom in design can be improved.

In addition, in the girder-to-girder connection structure using the girder-to-girder connection fittings described above, the first members of two adjacent building units are arranged with their protruding corners facing each other, and one bolt is inserted into the hole. By being fastened together, even if the diameter of the first member is large or small, by making the thickness of the first member the same, bolts of the same length can be used. The first members of adjacent building units can be connected. Therefore, the first members of adjacent building units can be connected by using a common bolt without being affected by the diameter of the first member.

In addition, the first members of four adjacent building units are arranged with their protruding corners facing each other, and two first members are arranged on both sides with a reinforcing plate that reinforces the girder between them. The first members of two adjacent building units can be connected with one bolt and reinforced with a reinforcing plate. Therefore, the rigidity of the girder-to-girder connection structure can be improved.

Further, by creating a unit building having the above-mentioned girder-to-girder connection structure, it is possible to construct a unit building having the girder-to-girder connection structure with common parts, regardless of the diameters of the columns and the first member.

1 is a perspective view showing the configuration of a unit building of Example 1. FIG. 1 is a perspective view showing the configuration of a building unit of Example 1. FIG. FIG. 2 is a perspective view showing the arrangement of building units in Example 1. FIG. FIG. 3 is a plan view showing a connecting fitting between girders in a region where four building units of Example 1 are connected; FIG. 3 is a perspective view showing the first member of Example 1. FIG. FIG. 3 is a perspective view showing the second member of Example 1. FIG. 3 is a diagram in which the girder-to-beam connection fitting of Example 1 is applied to a building unit with a large-diameter column, and is a plan view showing the girder-to-beam connection fitting in a region where four building units are connected.

EMBODIMENT OF THE INVENTION Hereinafter, embodiments for realizing a girder-to-girder connection fitting, a girder-to-girder connection structure, and a unit building according to the present invention will be described based on Example 1 shown in the drawings.

The girder-to-girder connection fittings, girder-to-girder connection structure, and unit building in Example 1 are unit buildings constructed by transporting building units manufactured in advance at a factory to a construction site and assembling a plurality of building units side by side at the construction site. applied to.

[Composition of unit building]
FIG. 1 is a perspective view showing the configuration of a unit building according to the first embodiment. The configuration of the unit building of Example 1 will be explained below.

As shown in FIG. 1, the unit building 1 is constructed by assembling a first floor building unit 10, a second floor building unit 20, and a roof panel 5 on a foundation 2.
[Building unit configuration]

FIG. 2 is a perspective view showing the configuration of the building unit 10 of the first embodiment. FIG. 3 is a perspective view showing the arrangement of the building unit 10 according to the first embodiment. The configuration of the building unit 10 according to the first embodiment will be described below.

As shown in FIG. 2, the building unit 10 includes a column 11 arranged at a corner, a floor girder 12 as a girder spanned between the lower ends of the columns 11 via a joint piece 16, and A box-shaped frame body is formed by a ceiling girder 13 as a girder spanned between the upper ends via a joint piece 17.

The building unit 10 includes, as main components, the above-mentioned frame body, a floor beam 14 as a small beam, a ceiling beam 15 as a small beam, a horizontal brace 18, and a connecting fitting 30 between large beams. Be prepared.

The pillar 11 is formed of, for example, a rectangular steel pipe in the shape of a square cylinder. The floor beam 12 and the ceiling beam 13 are formed of channel steel, for example.

The floor girder 12 is attached to the pillar 11 via a joint piece 16 made of steel. The ceiling girder 13 is attached to the pillar 11 via a joint piece 17 made of steel.

The floor beam 14 is formed of, for example, a rectangular steel pipe in the shape of a square cylinder. The floor beam 14 spans between the floor beams 12 on the long sides.

The ceiling beam 15 is formed of, for example, a rectangular steel pipe in the shape of a square tube. The ceiling beam 15 spans between the ceiling beams 13 on the long sides.

The horizontal braces 18 are arranged to intersect and connect diagonal corners of the ceiling beams 13 arranged to form a rectangle. In other words, the horizontal braces 18 are arranged to intersect and connect the columns 11 arranged diagonally in the building unit 10 in a plan view. The horizontal brace 18 serves to transmit horizontal forces applied to the building unit 10.

The girder-to-girder connection fitting 30 is arranged in a box-shaped frame body formed by the pillars 11, the floor girders 12, and the ceiling girders 13, in a portion where one pillar 11 is omitted. In the portion where the columns 11 are omitted, the floor beam 12 is attached to the inter-beam connection fitting 30 via the joint piece 16, and the ceiling beam 13 is attached to the inter-beam connection fitting 30 via the joint piece 17.

The building units 10 configured in this manner are arranged such that two adjacent building units 10 are arranged in two rows, as shown in FIG. In area A where four building units 10 are connected, the pillars 11 of each building unit 10 are omitted. Note that the building unit 20 on the second floor may also have a configuration in which the pillars 11 are omitted, similar to the building unit 10 on the first floor, or may have a configuration in which the pillars 11 are not omitted.

[Configuration of connecting fittings between girders]
FIG. 4 is a plan view showing the girder-to-girder connection fittings 30 in the area A where the four building units 10 of the first embodiment are connected. FIG. 5 is a perspective view showing the first member of Example 1. FIG. 6 is a perspective view showing the second member of Example 1. The configuration of the inter-girder connection fitting 30 of Example 1 will be described below. In addition, below, the connection fitting 30 between girders which connects between the ceiling girders 13 is demonstrated.

As shown in FIG. 4, the girder-to-girder connection fitting 30 is used between the ceiling beams 13 of adjacent building units 10 whose columns 11 are omitted.

The girder-to-beam connection fitting 30 includes a first member 40 and a second member 50.

As shown in FIG. 5, the first member 40 is made of steel and has a first piece 41 and a second piece 42 perpendicular to the first piece 41, and has an L-shaped cross section. The first member 40 has end plates 43 and 44 formed at both ends in the vertical direction.

The first piece 41 is formed to have a thickness T1. Two first piece through-holes 41 a are formed in the first piece 41 as holes that penetrate in the thickness direction of the first piece 41 .

The second piece 42 is formed to have a thickness T2 that is thinner than the thickness T1. That is, the thickness of the first piece 41 is formed to be thicker than the thickness of the second piece 42. Note that the first piece 41 and the second piece 42 may have the same thickness.

Two second piece through-holes 42 a are formed in the second piece 42 as holes that penetrate in the thickness direction of the second piece 42 .

The entered corner portion formed by the first piece 41 and the second piece 42 of the first member 40 is referred to as an entered corner portion 45 . In other words, the entered corner 45 is formed on the back side of the first member 40.

The protruding corner portion formed by the first piece 41 and the second piece 42 of the first member 40 is referred to as a protruding corner portion 46. In other words, the protruding corner portion 46 is formed on the front side of the first member 40.

An end plate 43 is formed at the upper end of the first member 40 . The end plate 43 is formed into a rectangular plate shape. The end plate 43 is formed with one end plate through hole 43a that penetrates in the thickness direction of the end plate 43.

An end plate 44 is formed at the upper end of the first member 40 . The end plate 44 is formed into a rectangular plate shape. The end plate 44 is formed with one end plate through hole 44a that penetrates in the thickness direction of the end plate 44.

The end plates 43 and 44 are formed such that the distance between the lower surface of the end plate 43 and the upper surface of the end plate 44 is a distance L1.

By inserting bolts and pins into the end plate through holes 43a and 44a, the temporary pillar can be detachably attached to the connecting fitting 30 between the girders.

As shown in FIG. 6, the second member 50 is made of steel and includes a main body 53 that supports the horizontal brace 18 and a base 50A that supports the main body 53.

The length of the base portion 50A in the vertical direction is formed to be a length L2 that is slightly shorter than the distance L1. The base 50A includes a first base 51 and a second base 52 that is orthogonal to the first base 51 and has an L-shaped cross section.

The entered corner portion of the base portion 50A of the second member 50, which is formed to have an L-shaped cross section, is referred to as an entered corner portion 55. In other words, the entered corner 55 is formed on the back side of the base 50A of the second member 50.

The protruding corner portion of the base portion 50A of the second member 50, which is formed to have an L-shaped cross section, is defined as a protruding corner portion 56.
In other words, the protruding corner portion 56 is formed on the front side of the base portion 50A of the second member 50.

The first base portion 51 is formed to have a thickness T3 that is thinner than a thickness T2. Two first base through holes 51 a are formed in the first base 51 as holes that penetrate in the thickness direction of the first base 51 . With the protruding corner 56 of the second member 50 in contact with the inlet corner 45 of the first member 40 and positioned in the horizontal and vertical directions, the first base through hole 51a is opened in the first piece. It is formed at the same position as the through hole 41a.

The second base portion 52 is formed to have a thickness T3. Two second base through holes 52 a are formed in the second base 52 as holes that penetrate in the thickness direction of the second base 52 . With the protruding corner 56 of the second member 50 in contact with the inlet corner 45 of the first member 40 and positioning in the horizontal and vertical directions, the second base through-hole 52a is opened in the second piece. It is formed at the same position as the through hole 42a.

The main body portion 53 is formed to extend in the horizontal direction from the corner portion 55 of the base portion 50A. The main body portion 53 is formed into a plate shape. The main body portion 53 is formed to have a thickness T3. The main body part 53 is formed with one main body through hole 53a that penetrates in the thickness direction of the main body part 53.

The first piece through hole 41a and the first base through hole 51a constitute a hole that integrates the first member 40 and the second member 50.

[Connection structure between girders]
As shown in FIG. 4, the inter-girder connecting fitting 30 configured in this manner is arranged between the ceiling girders 13 of adjacent building units 10 without the pillars 11. The first members 40 of four adjacent building units 10 are arranged with their protruding corners 46 facing each other. The first members 40 of four adjacent building units 10 are arranged with the first pieces 41 facing each other. The first members 40 of four adjacent building units 10 are arranged with the second pieces 42 facing each other.

Two rigid joint plates 72 are interposed between the first pieces 41 and the first pieces 41 . The rigid joint plate 72 is formed to have substantially the same length as the first piece 41 .

A reinforcing plate 70 is interposed between the second pieces 42 . That is, the two first members 40 are arranged on both sides with the reinforcing plate 70 in between. The reinforcing plate 70 reinforces the space between the ceiling beams 13. The length of the reinforcing plate 70 can be set to cover the entire length of the two ceiling girders 13 of adjacent building units 10.

The first base of one of the adjacent building units 10 is penetrated with the projecting corner 56 of the second member 50 in contact with the entering corner 45 of the first member 40 for positioning. The bolt 61 is inserted from the hole 51a and the first piece through hole 41a to the first base through hole 51a and the first piece through hole 41a of the other building unit 10 through the through hole of the rigid joint plate 72, and the nut is inserted. 62. Bolt 61 can be a high strength bolt.

As a result, the second member 50 of one of the adjacent building units 10 is attached to the first member 40 of one of the building units 10, and the second member 50 of the other building unit 10 is attached to the first member 40 of the other building unit 10. It is attached to the first member 40 of the other building unit 10. Further, among the adjacent building units 10, the first member 40 of one building unit 10 and the first member 40 of the other building unit 10 are connected via the rigid joint plate 72.

That is, the first member 40 and the second member 50 of one building unit 10 and the first member 40 and the second member 50 of the other building unit 10 are fastened together with one bolt 61.

With the projecting corner 56 of the second member 50 in contact with the entering corner 45 of the first member 40 and positioned, the second base of one of the adjacent building units 10 The second member 50 is attached to the first member 40 by inserting bolts 63 into the through hole 52a and the second piece through hole 42a.

Further, among the adjacent building units 10, the joint piece 17 of one building unit 10, the ceiling beam 13, the joint piece 17 of the other building unit 10, the ceiling beam 13, and the reinforcing plate 70 are connected to the bolts 75. and are joined by a nut 76.

The horizontal brace 18 is attached to the main body 53 of the second member 50 by inserting the bolt 77 into the main body through hole 53a via the attachment piece 19 attached to the tip of the horizontal brace 18.

[Function of girder-to-girder connection fittings, girder-to-girder connection structure, and unit building]
Hereinafter, the functions of the girder-to-girder connection fitting 30, the girder-to-girder connection structure, and the unit building 1 of the first embodiment will be explained. The girder-to-girder connection fitting 30 of the first embodiment is used between girders (ceiling girders 13) of adjacent building units 10 whose columns 11 are omitted, which constitute a frame body with the columns 11 and girders (ceiling girders 13). . The girder-to-girder connection fitting 30 includes a first member 40 provided in each of the adjacent building units 10 and a second member 50 that supports the horizontal brace 18 and is attached to each first member 40. The member 40 is formed into an L-shaped cross section by a first piece 41 and a second piece 42 perpendicular to the first piece 41, and the second member 50 has a main body part 53 to which the horizontal brace 18 is attached, and a main body part 53. The base 50A is formed into an L-shaped cross section by a first base 51 and a second base 52 perpendicular to the first base 51, and includes a first member 40 and a second base 50. The member 50 has holes (first piece through hole 41a, first base through hole 51a) that integrate the first member 40 and the second member 50 (FIG. 7).

Thereby, the second member 50 can be attached to the first member 40 by bringing the projecting corner 56 of the second member 50 into contact with the entering corner 45 of the first member 40 . Therefore, even if the diameter of the pillar 11 is large and the diameter of the first member 40 is large, as shown in FIG. 7, even if the diameter of the pillar 11 is small and the diameter of the first member 40 is small, as shown in FIG. The same second member 50 can be brought into contact with the first member 40 . As a result, the second member 50 can be shared and attached to the first member 40 without being affected by the diameter of the first member 40.

In the girder-to-girder connection fitting 30 of Example 1, the main body portion 53 is formed to extend in the horizontal direction from the corner portion 55 of the base portion 50A (FIG. 6).

Thereby, the second member 50 can be attached to the first member 40 with the protruding corner 56 side of the base 50A of the second member 50 in contact with the inner corner 45 of the first member 40. Therefore, even if the diameter of the pillar 11 is large and the diameter of the first member 40 is large, as shown in FIG. 7, even if the diameter of the pillar 11 is small and the diameter of the first member 40 is small, as shown in FIG. The same second member 50 can be brought into contact with the first member 40 . As a result, the second member 50 can be shared and attached to the first member 40 without being affected by the diameter of the first member 40.

Further, the force from the horizontal brace 18 can be dispersed more efficiently by providing the main body 53 on the entering corner 55 side of the second member 50 than on the protruding corner 56 side of the second member 50. be able to. Therefore, the rigidity of the connecting fitting 30 between the girders can be improved.

In the girder-to-girder connection fitting 30 of Example 1, the first member 40 includes end plates 43 and 44 provided at the ends in the vertical direction (FIG. 5).

Thereby, the rigidity of the first member 40 can be improved. Therefore, the rigidity of the connecting fitting 30 between the girders can be improved. Furthermore, the second member 50 can be positioned in the vertical direction with respect to the first member 40 with a simple configuration.

In the girder-to-beam connection fitting 30 of the first embodiment, the holes (first piece through hole 41a, first base through hole 51a) connect the protruding corner 56 of the base 50A of the second member 50 to the inlet corner of the first member 40. 45, the bolts 61 are inserted into the holes (first piece through hole 41a, first base through hole 51a) formed at the same position, and the second member 50 is attached to the first member 40. (Figure 4).

As a result, with the second member 50 positioned on the first member 40, the bolt 61 is inserted into the holes formed in the first member 40 and the second member 50 (the first piece through hole 41a, the first base It can be inserted into the through hole 51a). Therefore, the second member 50 can be easily attached to the first member 40.

In the inter-girder connection fitting 30 of Example 1, the thickness of the first piece 41 is thicker than the thickness of the second piece 42 (FIG. 5).

Thereby, the strength of the first piece 41 can be made stronger than the strength of the second piece 42. Even if the mounting structure between the large beams (ceiling beams 13) installed via the first piece 41 and the mounting structure between the large beams (ceiling beams 13) installed via the second piece 42 are different, the expected large beams ( It is possible to obtain the proof strength between the ceiling beams 13). Therefore, the degree of freedom in design can be improved.

In the girder-to-girder connection structure of Example 1, the first members 40 of two adjacent building units 10 are arranged with their protruding corners 46 facing each other, and the holes (first piece through hole 41a, first base through hole One bolt 61 is inserted into 51a) and tightened together (FIG. 4).

As a result, even when the diameter of the pillar 11 is large and the diameter of the first member 40 is large, as shown in FIG. 7, even when the diameter of the pillar 11 is small and the diameter of the first member 40 is small, as shown in FIG. By making the first members 40 have the same thickness, the first members 40 of adjacent building units 10 can be connected using bolts 61 of the same length. Therefore, the first members 40 of adjacent building units 10 can be connected by using a common bolt 61 without being affected by the diameter of the first member 40.

Moreover, with one bolt 61, the second member 50 can be attached to the first member 40, and adjacent first members 40 can be fixed to each other. Therefore, it is possible to provide an inter-girder connection structure with a reduced number of parts.

In the girder-to-girder connection structure of Example 1, the first members 40 of four adjacent building units 10 are arranged with their protruding corners 46 facing each other, and a reinforcing plate 70 for reinforcing between the girders (ceiling girders 13) is provided. Two first members 40 are arranged on both sides (FIG. 4).

Thereby, the first members 40 of two adjacent building units 10 can be connected with one bolt 61 and reinforced with the reinforcing plate 70. Therefore, the rigidity of the girder-to-girder connection structure can be improved.

Above, the girder-to-girder connection fitting, the girder-to-girder connection structure, and the unit building of the present invention have been described based on the first embodiment. However, the specific configuration is not limited to this embodiment, and changes and additions to the design are permitted as long as they do not depart from the gist of the invention according to each claim.

In the first embodiment, the first member 40 includes end plates 43 and 44. However, the first member may not include an end plate.

In the first embodiment, an example was shown in which the second member 50 was attached to the first member 40 with bolts 61 and 63. However, the second member may be attached to the first member by welding.

In the first embodiment, an example is shown in which one pillar 11 is omitted in one building unit 10. However, two or more columns may be omitted in one building unit.

In Example 1, an example was shown in which the girder-to-girder connection fitting 30 and the girder-to-girder connection structure of the present invention are used between the ceiling girders 13. However, the girder-to-girder connection fitting and the girder-to-girder connection structure of the present invention can also be used between floor girders.

In Example 1, an example was shown in which the girder-to-girder connection fitting 30 and the girder-to-girder connection structure of the present invention are applied to an area A where four building units 10 are connected. However, the girder-to-girder connection fitting, girder-to-girder connection structure, and unit building of the present invention can also be applied to areas where two building units are connected.

In Example 1, an example was shown in which the girder-to-girder connection fitting 30 and the girder-to-girder connection structure of the present invention are applied to a two-story unit building 1. However, the girder-to-girder connection fitting and the girder-to-girder connection structure of the present invention can be applied to a one-story unit building and a unit building of three or more stories.

1 Unit building 10 Building unit 11 Column 13 Ceiling beam (an example of a beam)
18 Horizontal brace 30 Connection fitting between girders 40 First member 41 First piece 41a First piece through hole (example of hole)
42 Second piece 43, 44 End plate 45 Inlet corner 46 Outer corner 50 Second member 50A Base 51 First base 51a First base through hole (an example of a hole)
52 Second base 53 Main body 55 Recessed corner 56 Extruded corner 61 Bolt 70 Reinforcement plate

Claims (4)

An inter-girder connection fitting used between girders omitting the pillars of adjacent building units, which constitute a frame body with columns and girders,
a first member provided in each of the adjacent building units;
a second member supporting a horizontal brace attached to each of the first members;
The first member is formed into an L-shaped cross section by a first piece and a second piece perpendicular to the first piece,
The second member includes a main body to which the horizontal brace is attached, and a base that supports the main body,
The base includes a first base and a second base perpendicular to the first base, and the base has an L-shaped cross section;
A hole is formed in the first member and the second member to integrate the first member and the second member,
The main body part is formed to extend horizontally from the corner of the base part. The connecting fitting between the girders. The girder-to-girder connection fitting according to claim 1, wherein the first member includes an end plate provided at an end in the vertical direction. The holes are formed at the same position with the protruding corner of the base of the second member in contact with the inlet corner of the first member,
The girder-to-girder connection fitting according to claim 1 or 2, wherein the second member is attached to the first member by inserting a bolt into the hole. An inter-girder connection structure using the inter-girder connection fitting according to any one of claims 1 to 3,
The first members of the two adjacent building units are arranged with their protruding corners facing each other,
A connecting structure between girders, characterized in that one bolt is inserted into the hole and the bolts are tightened together.