JPH11117439A - Fixing structure and fixing method for building material made of box-shape steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide joining structure of a building material made of box-shape steel by extensively improving conventional technology in a designing performance, workability and cost. SOLUTION: This fixing structure is constituted of a box shape steel-made ceiling common joist 10 having specified length, engagement projected parts 15a, 16a on which both end parts of this box shape steel-made ceiling common joist 10 fit and a pair of installation brackets 15, 16 having these engagement projected parts 15a, 16a. In this case, the both end parts of the box shape steel- made ceiling common joist 10 are fitted on the outside of the engagement projected parts 15a, 16a of the installation brackets 15, 16 installed on an installation surface separated by a constant interval of a building free to move and adjust in the common joist longitudinal direction along the engagement projected parts 15a, 16a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing structure and a fixing method for, for example, a box-shaped steel joist and various other box-shaped steel building materials.

[0002]

2. Description of the Related Art In a structure between a first-floor ceiling and a second-floor floor in a house, a construction method is usually employed in which a first-floor ceiling finishing material is directly stretched on a joist on the second floor. Due to an increase in noise insulation complaints,
The construction method of cutting the edge between the second floor joist and the ceiling joist and pasting the ceiling finishing material on the first floor is performed.

For example, in the examples shown in FIGS. 7 and 8, side joists 3 are provided on opposing wall frame members 2 on the first floor 1, and a plurality of side joists 3 are provided with a fixed interval between the side joists 3. Both ends of the provided wooden joist 4 are erected, and a ceiling base material 5 is attached to the ceiling joist 4. Meanwhile, lateral joist 3
On the upper part of the floor, the floor joists of the second floor are attached to the lower frame material (not shown) of the second floor.
Are provided at regular intervals, are inserted between the ceiling joists 4 from above, and the floor 7 of the second floor made of structural plywood is attached to the floor joists 6.

There is a gap between the tip of the ceiling joist 4 and the floor 7 on the second floor, and there is also a gap between the tip of the floor joist 6 on the second floor and the ceiling base material 5 on the first floor. Therefore, the first-floor ceiling portion and the second-floor floor portion are insulated, and in addition, an insulating material 8 such as rock wool or glass wool is provided at the upper end position of the ceiling joist 4 and between the second floor joists 6. By doing so, between the first floor and the second floor, vibration and sound are devised so as to be more effectively cut off.

Conventionally, a suspended ceiling joist is constructed of wood, but there are many variations in the material, and it is easy for the construction to become confused after the construction, and the cost is high. Attempts have been made to stabilize the quality of the suspended ceiling joists by using steel, and the supporting structure in this case is usually as shown in FIGS. As shown in each figure, both ends of the steel-made ceiling joist 10 having a rectangular section and a box-shaped steel ceiling joist 10 having a predetermined length are supported by mounting brackets 11.

The mounting bracket 11 is formed by bending a single metal plate having a predetermined thickness to open upward and laterally. The bottom plate 12 and both side plates 13 have a substantially U-shaped receiving portion. The wing plate 14 is integrally provided from the both side plates 13.

[0007] The mounting bracket 11 has a mounting wing plate 1.
4 is fixed to the lateral joist 3 using bolts and nuts on the wall frame member 2 on the first floor, and both ends of the box-shaped steel ceiling joist 10 are formed into a U-shaped bottom plate 12 and both side plates 13. This is a so-called stool-type support structure held inside the receiving portion.

[0008]

When the box-shaped steel ceiling joist 10 is supported by mounting brackets 11,
It has the following disadvantages. Hollow box-shaped steel ceiling joist 10
Is supported from the outside by the U-shaped receiving portion of the mounting bracket 11, so that the mounting bracket 11 and the box-shaped steel ceiling joist 10 are not sufficiently adhered to each other, and the steel ceiling joist 10 floats by a force from below. There is a risk. For this reason, slip prevention means such as fastening between the steel ceiling joist 10 and the mounting bracket 11 by bolts are required. The portion A in FIG. 9 has a double structure of the steel ceiling joist 10 and the mounting bracket 11, causing a level difference and a problem in finishing. Furthermore, in this double-structure part, it becomes difficult to perform fastening work such as screws.

The present invention has been made to solve the above-mentioned problems. In the above-mentioned box-shaped steel joists and other various box-shaped steel building materials, the feature that the cross section is hollow is utilized as much as possible, and the conventional type is used. It is an object of the present invention to provide a so-called swallow-type fixing structure to a building material and a fixing method, instead of the stool type support structure.

[0010]

In order to solve the above-mentioned problems, a box-shaped steel building material fixing structure according to the present invention comprises: a box-shaped steel building material having a predetermined length; The box-shaped steel building material comprises a pair of mounting brackets each having an engaging projection to which both ends of the building material are fitted. It is characterized in that it is fitted to the outside of the engagement protrusion of the metal fitting so as to be movable and adjustable in the longitudinal direction of the building material along the engagement protrusion. Further, in the present invention, one of the engagement projections of the pair of attachments has flexibility and is provided so as to be deviated from a straight line connecting the engagement projections of the opposed attachments. The engagement protrusion is characterized by being elastically restored to the inner surface of the box-shaped steel building material by press contact. In the present invention,
Width W ₂ of the root portion of at least one of the engagement projecting portions of the pair of mounting brackets is about 2m than the width W ₃ of the tip portion
m or less. Further, the method for fixing a box-shaped steel building material of the present invention is a method for fixing a box-shaped steel building material, comprising: The other end
The fitting fitting is fitted to the outside of the engaging protrusion of the one fitting and inserted into the inner part thereof, and is formed between the engaging protrusion of one fitting and the other end of the box-shaped steel building material. Utilizing the space provided, the box-shaped steel building material is aligned on a straight line connecting the engagement protrusions of the pair of mounting brackets, and then the box-shaped steel building material is slightly moved and adjusted in a retracting direction, and The fitting is fitted to the outside of the engaging projection of the mounting bracket. In the method for fixing a box-shaped steel building material according to the present invention, one of a pair of mounting brackets having an engaging projection is fixed to one of the mounting surfaces facing each other with a space between the buildings, and the other mounting bracket is connected to the other mounting bracket. One end of the box-shaped steel building material is engaged with the outside of the joint projection, and the other end of the box-shaped steel building material is
After fitting to the outside of the engagement protrusion of the one mounting bracket and inserting it into the inner part and fixing the other mounting bracket to the other of the opposed mounting surfaces, the box-shaped steel building material is The movement is slightly adjusted in the direction of the other mounting bracket.

According to the first to fourth aspects of the present invention, the box-shaped steel building material is held inclined with respect to the same straight line connecting the engaging projections of the pair of mounting brackets mounted on the mounting surface of the building. Insert one end of this box-shaped steel building material deeply into the engagement projection of one of the mounting brackets,
The box-shaped steel building material is positioned so as to be aligned on the same straight line connecting the engagement protrusions of the pair of mounting brackets, and the box-shaped steel building material is slightly moved back in the opposite direction to the insertion method, so that the box-shaped steel material is returned. Both ends of the steel building material can be held by the engaging projections of both mounting brackets. Further, according to the invention of claims 1 to 5 of the present invention, since the box-shaped steel building material is of a slide fitting type, the engagement state can be maintained even if its length slightly changes, and its length can be maintained. Adjustment is possible, and when applied to a timber building with dimensional accuracy variations, the workability is significantly improved. In addition, by pressing the engaging projection of the mounting bracket against the inner wall surface of the box-shaped steel building material, the end of the box-shaped steel building material is restrained. It is possible to suppress the deflection of about 10% of the building material made of shaped steel.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In each of the drawings, as a specific example of the box-shaped steel building material according to the present invention, a fixing structure of the box-shaped steel ceiling joist 10 is shown. It is attached to the lateral joist 3 of the building via the fittings 15 and 16. 2 is an upper frame material.

The box-shaped steel ceiling joist 10 has a predetermined length, has a rectangular cross section perpendicular to the longitudinal direction, and is hollow inside. This box-shaped steel ceiling joist 1
0, a pair of mounting brackets 15, 16 supported at both ends,
Each is formed by cutting a metal plate having a predetermined thickness into a predetermined shape and bending the metal plate.
The structures a and 16a are slightly different.

In each of the drawings, one mounting bracket 15 shown on the left side is composed of both side plates 17 and a front end connecting plate 18.
A substantially U-shaped engagement protrusion 1 which is open in the vertical direction.
5a, and has a mounting wing plate 19 formed by bending the base ends of both side plates 17 outward at right angles. Vertical dimension H of the engaging protrusion 15a in the mounting bracket 15, than the vertical dimension H ₁ of the hollow hole 20 of the box shaped steel ceiling joists 10 is provided slightly smaller, the engaging projection The dimension W in the width direction of 15 a is provided slightly smaller than the dimension W _{1 in} the width direction of the hollow hole 20 of the steel ceiling joist 10. Therefore, the box-shaped steel ceiling joist 1 is provided outside the engagement protrusion 15 a of the mounting bracket 15.
When the 0 end is fitted, the upper and lower inner walls of the steel ceiling joist 10 and the four corners are in close contact with the two end surfaces and the upper and lower edges of the engaging projection 15a with an appropriate pressing force. Sliding between them can be slid in the fitting direction, and rattling does not occur between the two.

An L-shaped notch 21 is formed in the mounting bracket 15 at the base end of the lower end edge of the both side plates 17 so as to cut into an L-shape. As shown in FIG. When the side joist 3 is attached to the side joist 3 by bolts and nuts 22, a corner 2 a of the upper frame member 2 supporting the side joist 3 is provided so as to fit into the L-shaped notch 21. Further, although the tip direct connection plate 18 in the engaging projection 15a is a flat plate and is connected to the both side plates 17 at a right angle portion, the front end connection plate 18 may not be a flat plate. May also be connected at a non-perpendicular portion.

Next, the other mounting bracket 16 shown on the right side
Is formed by bending a flat metal plate cut into a predetermined shape to form long flat plates 23 and a tip-shaped connecting plate 24, and a substantially flat-shaped engaging projection 1 which is open in the vertical direction.
6a, and further includes a mounting wing plate 25 formed by bending the base ends of the long side plates 23 outward at right angles. The engagement protrusion 16a of the mounting bracket 16
The vertical dimension H is slightly smaller than the vertical dimension H of the engaging projection 15a of the other mounting member 15,
Dimension W ₁ in the width direction of engaging projection 16a also is provided trivial and widthwise dimension W of the other engaging projected portion 15a. Therefore, as in the case of the other mounting bracket 15, when the end of the box-shaped steel ceiling joist 10 is fitted to the outside of the engaging projection 16a of the mounting bracket 16, the steel ceiling joist 10
At the upper, lower, left and right inner wall surfaces and the four corners, engaging projections 15 are provided.
Since both side surfaces and the upper and lower edges are closely contacted, they can slide in the fitting direction between each other, and there is no play between the two.

The engaging projection 16a of the mounting bracket 16
Can be bent in the thickness direction due to the elasticity of the metal plate, and the distal end side of the engaging protrusion 16a is oriented in the horizontal direction around the bent connection portion 26 between the base end of the long side plate 23 and the mounting wing plate 25. Is provided so as to be elastically displaceable. In addition, as shown in FIG. 2, when the mounting bracket 16 is formed, when the mounting bracket 16 is mounted on the lateral joist 3, the engaging projection 16a is formed by a straight line connecting the two mounting brackets 15 and 16 facing each other. S is displaced so as to be slightly inclined in the horizontal direction with respect to S. Specifically, the included angle θ between one of the both side plates 23 and the mounting wing plate 25 is 93 °, and the included angle θ ₁ between the other side plate 23 and the mounting wing plate 25 is 87 °.

Further, the protrusion dimension L of the engaging projection 16a on one mounting bracket 16 and the other mounting bracket 15
Projection dimension L ₁ of the engaging protrusion 15a of the, L> L ₁
The dimensional relationship is provided. As described later, the protrusion size is changed in consideration of the easiness of the operation of engaging the box-shaped steel ceiling joist 10 with the mounting brackets 15 and 16 and the engagement stability after fixing.

The base end of the lower end of the long side plate 23 of the mounting bracket 16 is cut into an L-shape to provide an L-shaped notch 27. As shown in FIG. 2
5 is attached to the lateral joist 3 with bolts and nuts 22, the corner 2a of the upper frame member 2 supporting the lateral joist 3
It is provided to fit into the notch 27. Further, as shown in FIG.
This is for ease of insertion when one end of the box-shaped steel joist 10 is inserted into the engagement projection 16a from a direction inclined with respect to the axis with respect to the axis thereof, and is not necessarily a mountain shape. Further, the upper and lower edges of the tip angle connecting plate 24 are tapered slopes 28, which are also steel ceiling joists 10.
For easy insertion into the engagement projection 16a.

A procedure for attaching the box-shaped steel ceiling joist 10 to the mounting brackets 15 and 16 will be described. First, a pair of mounting brackets 1 are attached to side joists 3 facing each other with a space between buildings.
5 and 16 are fixed facing each other. At this time, the mounting bracket 1
The cutouts 21 and 27 of 5 and 16 are inserted into the corners 2 of the frame material 2 on the wall.
Positioning by abutting on a allows easy positioning of the left and right mounting brackets 15 and 16 at the height level. Next, the box-shaped steel ceiling joist 10 is slightly inclined with respect to a straight line S connecting the opposed mounting brackets 15 and 16 as shown in FIG. The ceiling joist 10 is moved rightward along its axis while correcting the tilt position little by little, and its tip is fitted to the outside of the engagement projection 16a of one of the mounting brackets 16 and inserted to the back. Then, the ceiling joist tip 31 is brought into contact with the upper frame member 3 to stop it (FIG. 3A). Next, the box-shaped steel ceiling joist 10 is positioned so as to be aligned on a straight line connecting the engaging projections 15a, 16a of the pair of mounting brackets 15, 16. As shown in FIG. 3A, the length of the box-shaped steel ceiling joist 10 is determined by the length of the base protrusion 29 of the ceiling joist 10 and the engagement protrusion 1 of the one mounting bracket 15 at the time of insertion.
It is provided in such a size that a slight gap 30 is formed between it and the tip of 5a.

Next, as shown in FIG. 3 (B), the box-shaped steel ceiling joist 10 is slightly moved back in the direction opposite to the insertion direction from the position shown in FIG. Both ends of the joist 10 are simultaneously engaged with the respective engaging projections 15a, 16a of the mounting brackets 15, 16. When the box-shaped steel ceiling joist 10 is returned from the inclined position in FIG. 2 to the linear position connecting the three members in FIG. 3, the displaced engaging projection 16a of one of the mounting brackets 16 is forced by its elasticity. Bends in a direction different from the direction when it was formed, and steel ceiling joists 1
0, so that the engagement protrusion 16a
Is pressed against the inner wall of one side in the hollow hole 20 of the steel ceiling joist 10 by its elastic restoring force (spring back), whereby the box-shaped steel ceiling joist 10 is stably engaged and held, and it is in the longitudinal direction. Do not move. It is to be noted that the reason why the engaging projections 16a are deviated as described above is to improve the adhesion between the two members. , 16a are in close contact with the inner walls in four directions of the box-shaped steel ceiling joist 10 at an appropriate contact pressure.
There is no protruding displacement in the longitudinal direction, and the ceiling base material 5 is attached to the ceiling joist 10 so that the ceiling joist 1
A downward force acts on 0, and the pressing action between the inner wall of the ceiling joist 10 and the engagement protrusions 15a, 16a increases.

FIG. 5 shows another example of the mounting bracket of the present invention. In the example shown in FIG. 5, the right-hand mounting bracket 16 of the pair of left and right mounting brackets 15 and 16 has a slightly different planar shape than the mounting bracket 16 shown in FIG. width W ₂ of are provided in the large in the range of about 2mm or less than the width W ₃ of the tip portion. The center lines S ₁ through the chevron tip 32 of the engaging projection 16a is ₂ theta with respect to the straight line S ₁ connecting the centers of the left and right mounting brackets 15 and 16 are provided to be inclined about 3 ° . When the mounting bracket 16 is configured as shown in FIG. 5, the engaging protrusion 16a is tapered in a plane, so that one end of the box-shaped steel ceiling joist 10 is connected to the engaging protrusion 16a.
Can be fitted more easily. Other functions and effects of the mounting bracket 16 of FIG. 5 are the same as those of the mounting bracket 16 shown in FIG.

FIG. 6 shows still another example of the mounting bracket of the present invention. In mounting bracket 16 shown in FIG. 6, the width W ₂ of the root portion of the engaging projection 16a is provided on a large range of about 2mm or less than the width W ₃ of the tip portion,
The point of the flat tapered shape is the same as that of the mounting bracket 16 shown in FIG. 5, but the center line passing through the chevron tip 32 of the engaging projection 16a is the same straight line connecting the centers of the left and right mounting brackets 15, 16. 5 is slightly different from the configuration of the mounting bracket 16 in FIG. 6, the one end of the box-shaped steel ceiling joist 10 can be easily and reliably fitted to the engaging projection 16a.

In each set of a pair of right and left mounting brackets 15 and 16 shown in FIGS.
Each of the left mounting brackets 15 provided in a substantially rectangular shape in a plane may be provided in the same shape as the right mounting bracket 16 in each set. Further, in the example shown in FIGS. 1 to 4 of the present invention, a pair of right and left mounting brackets 15 and 1 are arranged in the following mounting order.
6 and box-shaped steel ceiling joist 10 can be attached to the building. First, the side joists 3 facing each other with a space between the buildings
, One of the pair of mounting brackets 15 and 16, for example, the mounting bracket 16 is fixed. Next, one end of the box-shaped steel joist 10 is fitted to the outside of the engaging projection 15a of the other mounting bracket 15 before being attached to the building, and the other end of the box-shaped steel joist 10 is connected to the one mounting bracket. The fitting protrusion 16a is fitted to the outside of the engaging protrusion 16a, and inserted into the inner part. Next, after fixing the other mounting bracket 15 to the opposing other side joist 3, the box-shaped steel joist 10 is slightly moved and adjusted in the direction of the other mounting bracket 15,
The work of attaching the box-shaped steel joist 10 to the building is completed. The same procedure can be applied to the mounting brackets 15 and 16 shown in FIGS.

The present invention simplifies the mounting brackets 15 and 16 and improves the adhesion between the mounting brackets 15 and 16 and the box-shaped steel ceiling joist 10 so that the mounting brackets 15 and 16 and the steel ceiling joist during construction are provided. The main objectives are to prevent "rattle" with 10 and to suppress the deflection. With respect to the above, the mounting brackets 15 and 16 are manufactured by bending a metal plate in two directions in a conventional product, whereas in the present invention,
Fabrication can be performed by simply bending the metal plate in one direction, and the production process can be omitted and cost can be reduced.

With respect to the above, by adopting a sliding structure in which the steel ceiling joist 10 and the mounting brackets 15 and 16 are fitted, the adhesion is improved in a range where both members overlap.
Prevention of "rattle" between the mounting brackets 15 and 16 and the steel ceiling joist 10 during construction and the effect of suppressing the deflection of the steel ceiling joist 10 are surely improved.

[0027]

According to the present invention, the conventional joint structure, that is, the structure in which the outside of the box-shaped steel building material is supported by the mounting brackets, is used to the fullest extent by utilizing the hollow cross section of the box-shaped steel building material. Instead, the engaging protrusions of the pair of mounting brackets are inserted into the hollow holes of the box-shaped steel building material, and the box-shaped steel building material is slid in the longitudinal direction and supported and fixed at a predetermined position. There are the following effects. The box-shaped steel building material is a slide fitting system and is not fastened to the mounting bracket with bolts and nuts, so its length can be adjusted, especially for wood frame materials with large dimensional accuracy variations. In the case of mounting, the workability is remarkably improved by the slide fitting method. Due to the close contact of the box-shaped steel building material and the mounting bracket with the appropriate contact pressure in the slide fitting portion over a predetermined range, and the constraining action of the building material, the steel ceiling building material is compared with the case without this restriction. About 10% or more of the bending effect was confirmed. When the mounting bracket is manufactured by bending a metal plate, only one bending direction is required, so that the manufacturing process can be omitted and the cost can be reduced. In addition, since the end of the steel building material is fitted to the outside of the engaging protrusion of the mounting bracket, the engaging protrusion is located inside the building material at the overlapping portion of both members, and the tip position of the engaging protrusion is In this case, no step is formed on the outside of the building material, so that deterioration of workability can be avoided. By pressing the engaging projection of the mounting bracket against the inner wall of the box-shaped steel building material by utilizing the springback, the effect of closely attaching the two members is further improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a fixing structure of a box-shaped steel ceiling joist according to the present invention.

FIG. 2 is a cross-sectional plan view showing an initial step when the box-shaped steel ceiling joist is fitted to a mounting bracket.

FIG. 3A is a cross-sectional plan view showing the same intermediate process.
(B) is a cross-sectional plan view showing a final step.

FIG. 4 is an exploded perspective view of a box-shaped steel ceiling joist and a mounting bracket.

FIG. 5 is a cross-sectional plan view showing a fixing structure of a box-shaped steel ceiling joist according to another example of the present invention.

FIG. 6 is a cross-sectional plan view showing a fixing structure of a box-shaped steel ceiling joist according to still another example of the present invention.

FIG. 7 is a perspective view of a ceiling viewed from the first floor of a building showing a state in which a wooden joist is attached as a conventional example.

8 is a cross-sectional view showing a relationship between a first floor ceiling joist and a second floor floor joist in the ceiling portion of FIG. 7;

FIGS. 9A and 9B are a plan view and a side view showing a conventional fixing structure for a box-shaped steel ceiling joist.

FIG. 10 is an exploded perspective view of a conventional box-shaped steel ceiling joist and a mounting bracket.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st floor 2 Wall frame material 3 Side joist 4 Ceiling joist 5 Ceiling base material 6 Floor joist 7 2nd floor 8 Insulation material 10 Box-shaped steel ceiling joist 11 Mounting bracket 12 Floor plate 13 Side plate 14 Mounting wing plate 15 Mounting bracket 15a Engagement protrusion 16 Mounting bracket 16a Engagement protrusion 17 Side plate 18 Tip connecting plate 19 Mounting wing plate 20 Hollow hole 21 L-shaped notch portion 22 Bolt, nut 23 Long side plate 24 Tip angle connection plate 25 Mounting wing Plate 26 Bending connection part 27 L-shaped notch part 28 Tapered slope 29 Ceiling joist base end 30 Gap 31 Ceiling joist tip 32 Chevron tip

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Koji Sugita, Inventor Koji Sugita 2-6-3 Otemachi, Chiyoda-ku, Tokyo New Nippon Steel Corporation (72) Inventor Yoshimitsu Murahashi 2-chome, Otemachi 2-chome, Chiyoda-ku, Tokyo No. 3 Inside Nippon Steel Corporation

Claims (5)

[Claims] 1. A box-shaped steel building material having a predetermined length, and a pair of co-linearly provided engaging projections at which both ends of the box-shaped steel building material are fitted. It consists of a mounting bracket, both ends of the box-shaped steel building material,
It is characterized in that it is fitted to the outside of the engaging protrusion of the mounting bracket attached to the mounting surface facing the building at an interval of the building so as to be movable and adjustable in the longitudinal direction of the building material along the engaging protrusion. Fixed structure for box-shaped steel building materials. 2. An engaging projection of one of said pair of mounting brackets is flexible and is provided so as to be deviated from the same straight line connecting said engaging projections of said mounting bracket with each other. 2. The fixing structure for a box-shaped steel building material according to claim 1, wherein said engaging projection is pressed into engagement with an inner surface of said box-shaped steel building material by elastic restoring force. 3. The width dimension W ₂ of a root portion of at least one of the engagement projections of the pair of mounting brackets is larger than the width dimension W ₃ of a tip portion by about 2 mm or less.
Or the fixing structure of the box-shaped steel building material of 2. 4. A pair of mounting brackets each having an engaging projection are fixed to opposing mounting surfaces of the building with an interval therebetween, and the other end of the box-shaped steel building material is connected to the one mounting bracket. Is fitted to the outside of the engaging projection and is inserted to the back, and the space formed between the engaging projection of one of the mounting brackets and the other end of the box-shaped steel building material is used. Then, this box-shaped steel building material is aligned on a straight line connecting the engagement protrusions of the pair of mounting brackets, and then the box-shaped steel building material is slightly moved and adjusted in the pulling-back direction to engage the other mounting bracket. A method for fixing a box-shaped steel building material, wherein the method is fitted to the outside of the joint projection. 5. One of a pair of mounting brackets having an engaging projection is fixed to one of the mounting surfaces opposed to each other with a space between the buildings, and a box-shaped steel member is formed outside the engaging projection of the other mounting bracket. One end of the building material is engaged, and the other end of the box-shaped steel building material is fitted to the outside of the engaging protrusion of the one mounting bracket and inserted into the back, and the other mounting bracket is connected to the other mounting bracket. A method for fixing a box-shaped steel building material, wherein the box-shaped steel building material is slightly moved and adjusted in the direction of the other mounting bracket after being fixed to the other of the opposed mounting surfaces.