JP2003013547A - Building member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a building member excellent in rigidity and yield stress capable of enhancing the assembling property by the same member and surely preventing a local deformation. SOLUTION: A beam member 1 comprises a vertical pair of flange parts 2 and 3 and a web part 4, which hare continuously formed by bending a thin steel product 11, both the upper and lower flange parts 2 and 3 has a closed sectional shape, the web part 4 has a sectional shape substantially linearly continuously located between one-side end parts 2a and 3a of both the flanges 2 and 3. Both the flange parts 2 and 3 have a sectional shape symmetric in relation to the horizontal central axis of the web part 4, and the mutually opposed surfaces of both the flanges 2 and 3 have inclinations as extending to the outside stepwise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building member used as a beam for supporting a floor board in a small-scale steel structure building such as a steel house.

[0002]

As a member for constructing a small-scale steel structure building such as a steel house, surface-treated channel steel, which is lighter in weight than wood, easy to form, inexpensive and excellent in durability, is preferably used. ing. This channel steel is manufactured by cold forming a galvanized thin steel sheet having a plate thickness of about 1 mm, and is used for supporting roofs and walls in addition to small-scale steel structure buildings such as steel houses. Widely used as the next structural member.

Conventionally, in a member used in a steel house of this type, a channel steel a as shown in FIG.
As shown in FIG. 4 (b), the web portion b of the pair of channel steels a
An assembly material is used in which the web portion b and the upper and lower flange portions c and d are joined to each other by joining means e such as a bolt or a drill screw so as to have an I-shaped cross section. There is.

In such a conventional beam, since the ratio of the thickness to the height (height / thickness) of the web portion b of the channel steel a becomes large, the proof stress of the member is the shear buckling of the web portion. In many cases, the allowable span is small and the performance of the channel steel section cannot be fully utilized. Moreover, since the thin steel plate is made of the grooved steel a having an open shape with a plate thickness of about 1 mm, the twisting resistance is small, and the fulcrum portion where a concentrated force acts is shown in FIG.
As indicated by dotted lines in (a) and (b), respectively, there is a problem that local fracture (clip ring) is likely to occur due to shear buckling of the web portion b.

Conventionally, in place of the channel steel, various frame structure embodiments as shown in FIG. 5 have been proposed. Figure 5
In the first embodiment shown in (a), the upper and lower flange portions b and c formed of the thin steel material a have a vertically and horizontally asymmetric closed cross-sectional shape with respect to the web portion d. It is used for materials.

The second embodiment shown in FIG. 5B is a first embodiment.
Similar to the above embodiment, the upper and lower flange portions b and c formed of the thin steel material a have an I-shaped closed vertical and horizontal cross-sectional shape via the web portion d.
As shown in FIG. 5 (c), the ends of the thin plate steel material a that bends the upper and lower flange portions b and c together with the thin plate steel material a that forms the web portion d are joined by a joining means e such as caulking.
Are joined by.

By thus forming the upper and lower flange portions b and c formed of the thin steel material a in a closed cross-sectional shape, the torsional resistance is increased and the cross-sectional shape of the member is hard to be deformed, The strength and rigidity are improved.

[0008]

However, the above-mentioned FIG.
The member having the conventional structure shown in (1) has various problems in terms of manufacturing, construction, assembly, and local destruction of the web. The first problem is that the shape shown in FIG. 5 (a) complicates the shape and increases the manufacturing cost.

The second problem is a problem as shown in FIG. 6, which is seen when a member having a form as shown in FIG. 5 (b) is used as a beam for supporting a floor board, for example. That is, in such a floor beam case, a face plate F such as a structural plywood is often placed and joined on the upper flange portion b formed of the thin steel material a. In such joining with the face plate F, when the drill screw S is driven so as to penetrate from the upper side of the face plate F to the upper flange portion b, the web portion d is an intermediate portion in the lateral direction of the flange surface of the upper flange portion b. Since it is located corresponding to, drill screw S
It often happens that the butt hits the web portion d and cannot be placed.

Therefore, it is necessary to pull out the driven drill screw S once, shift the driving position, and then mount the drill screw S again. As a result, the construction work at the time of placing the drill screw S increases.

The third problem is seen when the same members are assembled back-to-back to form an assembly material like the channel steel shown in FIG. 4 (b). By using the assembly material as shown in FIG. 4B, the proof stress and the rigidity can be increased without changing the height of the member, but as shown in FIG.
When the same members having the configuration as shown in FIG. 5 (b) are assembled back-to-back to form an assembly material, a deformation preventing material f is interposed between both members as a spacer, and a joining means e such as a bolt / nut is provided. Need to be joined together. In such a case, there is a problem that the assembly cost of the assembly material increases.

A fourth problem is that the web portion d between the upper and lower flange portions b and c formed of the thin steel material a is continuous through the bent portion and is linearly continuous. In particular, in the case of the shape shown in FIG. 5 (a), an additional bending moment is likely to be generated in the bent portion of the web portion d, which causes local destruction of the web portion d, which causes habitability. There is a problem that it also has an adverse effect.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a building member which is excellent in rigidity and proof stress and has an improved assembling property by the same member.

[0014]

In order to solve such a problem, the present invention is constructed as follows.

According to a first aspect of the present invention, in a building member in which a pair of flange portions and a web portion are continuously bent by a thin steel material, both flange portions have a closed cross-sectional shape, and the web portion is It is characterized in that it has a cross-sectional shape in which it is positioned substantially linearly continuously between the end portions on one side of both the flange portions.

A second invention is characterized in that, in the first invention, the both flange portions have a closed cross-sectional shape symmetrical with respect to a horizontal central axis of the web portion.

A third aspect of the present invention is characterized in that, in the first and second aspects, the ends of the thin sheet steel material that bends the flange portions are caulked together with the thin sheet steel material that forms the web portion. And

A fourth invention is characterized in that, in the first to third inventions, the facing surfaces of the both flange portions have an inclination angle so as to widen outward.

A fifth aspect of the invention is characterized in that, in the first to third aspects of the invention, the opposing surfaces of the two flange portions have an inclination angle such that they gradually expand toward the outside.

[0020]

In the construction member according to the present invention, the pair of flange portions continuously bent by the thin steel material have a closed cross-sectional shape, while the web portion is substantially straight between the one end portions of both flange portions. The cross-sectional shape is formed by continuously arranging. Therefore, resistance to twisting and local breakage (clip ring) of the web is increased, and rigidity of the entire member can be improved. This makes it possible to prevent the occurrence of various bucklings as in the past.

Further, since the web portion is positioned substantially linearly continuously between the end portions on one side of both flange portions, it is possible to reduce the assembly cost of the assembly material by the same member.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings shown in FIGS. FIG. 1 shows a first embodiment of a floor frame supporting beam used as a member of a building frame structure, for example, a steel house according to the present invention.

As shown in FIG. 1, the beam member 1 is composed of upper and lower flange portions 2 and 3 and a web portion 4 connecting the flange portions 2 and 3. The upper and lower flange portions 2 and 3 have a rectangular closed cross-sectional shape, and the web portion 4 is positioned substantially linearly between the one end portions 2a and 3a of the upper and lower flange portions 2 and 3, respectively. And an overall cross-sectional shape formed in a groove shape.

Then, the upper and lower flange portions 2, 3 of the beam member 1
Has a vertically symmetrical shape with respect to the horizontal central axis O-O of the web portion 4 and has a laterally asymmetrical shape with respect to the vertical central axis Q-Q.
3b has an inclination angle θ such that it spreads outward,
The inclination angle θ is set in the range of 20 ° to 50 °.

In order to manufacture the beam 1 described above, the plate thickness is 0.5 to 3.2 mm, preferably 1.2 to 1.6 mm.
The thin steel material 11 is used. The thin steel plate 11 is cold-formed to continuously bend the upper flange-side thin steel plate 12, the lower flange-side thin steel plate 13 and the web-side thin steel plate 14, and the upper and lower flange-side thin steel plates. 12,
End portions 11a, 11 of the thin steel material 11 that bends 13
b is joined with the thin steel sheet material 14 on the web portion side by caulking.

By the way, the upper and lower flange portions 2 of the beam 1 are
The reason why the opposing surfaces 2b and 3b of 3 are set to expand outward with the inclination angle θ in the range of 20 ° to 50 ° is as follows. That is, as shown in FIG. 1, when a vertically downward load is applied on the upper flange portion 2, a vertically upward reaction force acts as a reaction at the support point on the lower flange portion 3 side. Then, such a vertically downward load is applied to the lower flange portion 3 via the web portion 4.
And the reaction force in the vertically upward direction acts on the facing surface 2b of the upper flange portion 2 via the web portion 4.

At this time, if the inclination angles θ of the facing surfaces 2b and 3b of the upper and lower flange portions 2 and 3 are 20 ° or less, a large additional bending acts on the upper and lower flange portions 2 and 3 and the sectional shape Deforms, and the load and reaction force
Cannot be effectively transmitted to both the upper and lower flange portions 2 and 3 side through, and the strength of the entire member may be reduced. On the other hand, when the inclination angle θ is 50 ° or more, the web 4
However, there is a problem that the length becomes short and the length cannot be sufficiently secured.

FIG. 2 shows a second embodiment according to the present invention. In the second embodiment, the upper and lower flange portions 2 and 3 of the beam member 1 are provided with recesses 2 having V-shaped cross sections on the flange surfaces 2c and 3c.
1, 31 are formed on the central axis Q-Q in the vertical direction, and the facing surfaces 2b, 3b are formed on the central axis Q-Q in the vertical direction.
It has a form in which it is further expanded in two steps outward from the upper central portion with an inclination angle θ1 (θ1> θ). As a result, the opposing surfaces 2 of the upper and lower flange portions 2 and 3
b, 3b and flange surfaces 2c, 3c are increased in yield strength and rigidity.

FIG. 3 shows a third embodiment according to the present invention. This embodiment is an example in which the building member in the first embodiment described above is applied to a roof truss of a steel house as an assembly material. In this embodiment, two building members 101, 101 are back-to-back to form an assembly material 100, for example, a truss diagonal member 200 made of channel steel and a bolt / nut 201 via a metal joint 202. Have. Here, the joining hardware 202 is used as the building member 10
Positioning between 1 and 101 enables smooth transmission of force.

In the above-described embodiment, for example, the steel house has been described as an example, but it can be used as another structural member. In addition, it goes without saying that the present invention can be variously modified and implemented without departing from the scope of the invention.

[0031]

As described above, according to the building member of the present invention, the pair of flange portions which are continuously bent by the thin steel material have the closed cross-sectional shape, while the web portion has the both sides. Since it has a cross-sectional shape in which it is positioned substantially linearly continuously between the end portions on one side of the flange portion, it is possible to increase the resistance to twisting and local breakage due to the action of a large force. As a result, it is possible to prevent the conventional strain deformation of the cross-sectional shape, web shear buckling, and overall buckling due to twisting.

Further, since the web portion is positioned substantially linearly continuously between the end portions on one side of both flange portions, it is possible to reduce the assembly cost of the assembly member made of the same member.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a first embodiment of a building member according to the present invention.

FIG. 2 is a sectional view schematically showing a second embodiment according to the present invention.

FIG. 3 is a sectional view schematically showing a third embodiment according to the present invention.

4A and 4B respectively show beam members for supporting a conventional floorboard, FIG. 4A is a sectional view schematically showing an embodiment of channel steel, and FIG. 4B is a mode in which channel steel is joined back to back. It is sectional drawing which shows roughly.

5A and 5B show a conventional building member having a closed cross-section, wherein FIG. 5A is an explanatory view showing a first embodiment, FIG. 5B is an explanatory view showing a second embodiment, and FIG. It is explanatory drawing which shows a state.

FIG. 6 is an explanatory view showing a construction state of a floor board surface material on a beam material.

FIG. 7 is an explanatory view showing a joined state of the assembly materials by the same member.

[Explanation of symbols]

1 Building materials (beams) 2 Upper flange 2a end 2b facing surface 2c Flange surface 21 recess 3 Lower flange 3a end 3b Opposing surface 3c Flange surface 31 recess 4 Web section 11 Thin plate steel 11a end 11b end 12 Thin plate steel on the upper flange side 13 Lower flange side thin plate steel 14 Web side thin steel plate 15 Caulking joint 100 assembly materials 101 structure 101 structure 102 bolts and nuts 200 Roof truss diagonal (channel steel) 201 bolts and nuts 202 Joining hardware OO Horizontal center axis Q-Q Vertical central axis θ Inclination angle of facing surface θ1 Inclination angle of facing surface

Claims (5)

[Claims] 1. A building member in which a pair of flange portions and a web portion are continuously bent from a thin steel material, wherein the both flange portions have a closed cross-sectional shape, and the web portions include the both flange portions. 2. A building member having a cross-sectional shape formed by continuously and substantially linearly arranging between the one side end portions thereof. 2. The building member according to claim 1, wherein the both flange portions have a cross-sectional shape that is symmetrical with respect to a horizontal center axis of the web portion. 3. The construction according to claim 1 or 2, wherein the ends of the thin plate steel material that bends the both flange portions are caulked together with the thin plate steel material that forms the web portion. Element. 4. The building member according to claim 1, wherein the facing surfaces of the two flange portions have an inclination angle so as to spread outward. 5. The building member according to claim 1, wherein the facing surfaces of the both flange portions have an inclination angle that gradually expands outward.