JP2001329654A - Steel truss joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide section steel members which are suitable for a roof skeleton of a building and can be easily joined together, and to provide a steel truss joint structure using the section steel members. SOLUTION: A short-side web 1 and long-side flanges 2a and 2b cooperatively form a structure having an almost U-shaped cross section, and the tips of the long-side flanges 2a and 2b are inward bent by 90 deg. or more to form lips 2a' and 2b', respectively, to thereby form the shape steel member for the steel truss, having an almost C-shaped cross section. When the thus formed shape steel members are joined together by alternately superposing the respective flanges 2a and 2b on each other, at least one of the interfering lips 2a' and 2b' is bent and flatten in parallel with the flanges 2a and 2b, to thereby form the steel truss joint structure. On the other hand, when the truss members are joined together by employing the shape steel members for the steel truss which each have an internal dimension almost equal to an external dimension of a wooden material 6, and fitting the wooden material into the shape steel members 6, the lips 2a' and 2b' are folded and flattened in parallel with the flanges 2a and 2b, to thereby form another steel truss joint structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel member for a steel truss suitable for a roof frame of a building and a steel truss using the same.

[0002]

2. Description of the Related Art Conventionally, as a roof frame made of a thin steel plate shaped steel member, a C-shaped cross section has a web outer dimension substantially the same as a long side dimension of a wooden two-by-four lumber cross section, and a flange outer dimension of a wooden two-by-four lumber cross section. Shaped steel members with the same length on the short side and open on one side of the long side, U-shaped cross-section, the inside dimensions of the web are almost the same as the long sides of the wooden two-by-four lumber section, and the inside dimensions of the flange are wooden. A roof truss of a steel framed wall construction structure which is substantially the same as the short side dimension of the two-by-four lumber cross section and is formed from a shaped steel member having one long side open is used. This truss is generally composed of upper and lower chords and lattices made of a shaped steel member with a C-shaped cross section, and is directly screw-bonded with the web surfaces back to back. It is constituted by either of joining, cutting off the flange portion of the shaped steel member, and superimposing and joining by screws, or a combination thereof. The U-shaped cross section steel member uses a C-shaped cross section, that is, an open cross section steel material as the truss member. Used in combination as a cover material.

[0003]

The above-mentioned roof truss has the advantages of being lighter in weight and higher in strength than wooden truss.
In addition, the steel truss is thinner than a steel truss used for a steel frame prefabricated house, and since it is assembled with screws instead of bolts or welding, it has advantages such as light weight and easy processing and joining.

[0004] However, the above-mentioned method has an advantage that a joining member such as a gusset plate is not required. However, since the steel members are joined back to back, the width of the truss member is reduced by the height of the flange of the truss member. Twice as much as
There is a drawback that the transportation efficiency decreases, and the above method requires cost, such as mounting a gusset plate and increasing the number of screws.
This increases the time and effort, and the above method has a problem that it takes time to cut off the flange.

In addition, since a steel material having a C-shaped cross section, that is, an open cross section, is used as a truss member, the members are joined by driving a large number of screws into a web portion.
The truss configured in this way has a drawback that it is difficult to attach the truss fixing hardware because there are many screw heads at the joints.Furthermore, it is not possible to mount the truss fixing metal etc. on the open section side as it is There is a problem that cannot be done.
Therefore, a box-shaped closed cross-section is formed by combining a U-shaped section steel member as a cover material at a portion where a metal fitting for fixing to a wall member is to be attached, and the metal fitting is mounted on the side of the U-shaped cross-section steel member. However, this leads to an increase in the number of members and an increase in labor.

Further, in the case where the above-mentioned method is employed in which flanges are overlapped and joined by using a steel member having a U-shaped cross section with one long side opened as described above, the flange dimension becomes wooden. Due to the short side dimensions of the material, the overlap margin of the flange cannot be made large, so that the joint area becomes small, and it may not be possible to strike the required number of screws in structural strength. Also, even if a truss shape is configured,
Since the member section height is small, the section performance is small, which is disadvantageous in structural strength. Therefore, it is necessary to take measures such as increasing the thickness of the plate and increasing the number of lattice materials in order to secure the necessary cross-sectional performance.
It is disadvantageous in terms of cost.

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned problems, and provides an easily joined shaped steel member suitable for a roof frame of a building and a steel truss structure using the same. It is intended to be.

[0008]

In order to achieve such an object, the present invention has the following arrangement. (1) The cross section is formed into a substantially U-shape by the web on the short side and the flange on the long side, and the tip of the long side flange is bent inward by 90 ° or more to form a lip. A steel member for a truss made of a letter shape. (2) The steel truss shaped steel member according to the above (1), wherein the inner dimension is substantially equal to the outer dimension of the wooden material. (3) When the steel truss shaped steel members according to the above (1) or (2) are alternately overlapped with the flanges and joined together, at least one of the interfering lips is folded in parallel with the flange. The joint structure of steel truss. (4) A truss joint, wherein the lip is folded in parallel with the flange when the truss member is joined by inserting a wooden member into the steel truss shaped steel member according to (2). Construction.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing one embodiment of a steel truss shaped steel member of the present invention.

[0010] The section of this shaped steel member has a web 1 of short side.
And long side flanges 2a and 2b to form a substantially U-shape, and furthermore, bend the distal ends of the long side flanges 2a and 2b inwardly by 90 ° or more to form lip portions 2a ′ and 2
b 'is formed to have a substantially C-shape. The lip angle may be arbitrarily set in the range of 90 ° to 180 ° (inwardly folded state). As the steel material, for example, a hot-dip galvanized steel sheet having a thickness of about 1.0 mm, a zinc aluminum alloy-plated steel sheet,
Alternatively, a precoated steel sheet or the like is used, and the steel material strength is at least 270 N or more, and a 400 N class is desirable.

An example of a cross-sectional dimension of the section steel member is a web internal dimension w = 38 mm, a flange internal dimension h = 89 m.
m, lip length = 15 mm, and lip angle = 90 °. Since this inner dimension is equal to the cross-sectional outer dimension of the wooden two-by-four lumber 204, as shown in FIG.
Materials can be fitted. In addition, materials corresponding to arbitrary wooden materials such as 206 materials and 208 materials are also feasible.

When a truss is constructed using this shaped steel member, the lip portion is folded inward only at a necessary portion and crushed flat to assemble. Processing is easy because of the small thickness. When joining shaped steel members, at least one of the interfering lips is folded.

FIGS. 2 to 5 show an embodiment of the steel truss of the present invention using the above-mentioned shaped steel member. FIG. 2 is a front view, and FIG. 3 is a sectional view taken along line III-III of FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, and FIG. 5 is a sectional view taken along the line VV in FIG.

As shown in FIG. 2, this steel truss is composed of two upper chords 3a and 3b and a lower chord 4, and the dimensions thereof are, for example, 2.7 m in span and 0.8 m in height.
1 m. The upper chord members 3a and 3b are each extended, for example, by 0.5 m from the joint between the upper chord members 3a and 3b and the lower chord member 4, thereby forming an eave.

When assembling the truss, as shown in FIG. 3, the upper chords 3a and 3b are arranged with the opening side of the shaped steel member facing downward, and the lower chord 4 is arranged with the opening side of the shaped steel member facing upward. .

As shown in FIGS. 2 and 4, the top of the truss is required by folding the lips on one side of the upper chord members 3a and 3b, whose opening sides are both downward, and overlapping the flanges to join the flanges on both sides. You can beat the number of screws. Here, for example, two tapping screws 5 each having a nominal diameter of 4.2 mm are joined to each flange.

The ends of the truss are, as shown in FIGS. 2 and 5, an upper chord member 3a or 3b and a lower chord member 4 whose opening sides face each other.
, The lip on one side is crushed, the flanges are overlapped, and the same lip is used, for example, with three tapping screws 5 each. With this configuration, the assembled truss has a box-shaped cross-section at the joint with the wall, which eliminates the need for a cover material for mounting hardware, and reduces processing labor and the number of parts. Becomes possible,
The construction is streamlined and truss can be supplied at lower cost than before.

The truss assembled as described above is arranged on a separately assembled wall with the truss member core and the vertical wall of the wall aligned, and the upper frame and the flange surface of the truss member are, for example, angle hardware (L). (-89 plate thickness: 1.0 mm) and fixed by tapping screws. Further, the eaves portion and the wall are tightly fastened with the stopper metal to complete the installation.

As shown in FIG. 5, it is also possible to form a closed cross-section by alternately stacking the flanges with the opening portions facing each other. The closed cross section assembled in this manner is used in a direction in which the long sides are lengthened in order to effectively use the cross-sectional performance as a bending material.

In the case of combining a shaped steel member having an opening on the long side as in the prior art, a closed section is formed by screwing a short side portion. Screw heads may interfere with each other. Also, it is difficult to use because the screw head interferes when attaching the ceiling surface material. On the other hand, as described above, if the short side side openings are faced to each other and the long side flanges are overlapped and a screw is punched to form a closed cross section, the screw head is located on the side surface, so there is an obstacle in use. There is a merit that will not be.

6 to 8 show another embodiment of the joint structure of the steel truss according to the present invention. FIG. 6 is a front view, FIG. 7 is a bottom view, and FIG. It is sectional drawing which follows the VIII line.

When joining steel members in a conventional steel truss, a flat gusset plate is usually used. In the case of a shaped steel member with a long cross section that is open, as is conventionally used, a gusset plate is attached to the web portion with screws, or a shaped steel member is screwed in, but the gusset plate has an out-of-plane rigidity. Is weak, and the stress point is shifted from the center of gravity, so that the torsion easily occurs. Such problems can be alleviated to some extent by making the gusset plate a more rigid member, but the thickness of the steel plate increases and the number of mounting screws increases, so the weight increases,
Construction efficiency also drops significantly.

On the other hand, as shown in FIGS.
Upper chord material 3a or 3 of the truss using the shaped steel member of the present invention
b and the lower chord member 4 are fitted inside both steel members to be joined to both ends of an existing wooden material 6 having a cross-sectional outer dimension substantially equal to the cross-sectional dimension of the shaped steel member, If it is constituted by joining with a tapping screw 5 or a nail 5a or the like from the outside, it is possible to obtain a joint having high workability and high rigidity in which twisting hardly occurs.

In this case, as shown in FIG.
Alternatively, 3b folds the lip that interferes with the wooden material 6 inward, but it may be folded in an acute angle in advance, insert the wooden material 6, and apply force from the outside to crush the lip portion.

On the other hand, since the lower chord member 4 has a normal dimension within the cross section substantially equal to the cross-sectional outer dimension of the wooden member 6, the wooden member 6 can be fitted without folding the lip inward as shown in FIG.

As an example of the dimensions, when the cross-sectional dimension of the shaped steel member is 89 mm on the long side and 38 mm on the short side, the cross-sectional outer dimension of the wooden material 6 is 89 mm on the long side and 38 mm on the short side, and the length is 25 mm.
0 mm. This length depends on the required strength of the joint. By configuring the joint in this way, it is possible to easily increase the bending, shear, and buckling strength of the joint.

As shown in FIG. 9 (a), it is also possible to fit the wooden material 6 into the eaves of the truss. In this form, the heat bridge at the joint between the truss and the wall can be reduced because the portion that becomes the thermal bridge, such as the eaves, is replaced with steel having high heat conduction resistance from wood. Wooden eaves may be installed on site. In this case, the size of the truss to be carried into the site can be reduced, so that there is an advantage that the transportation efficiency is improved.

Further, as shown in FIG.
The wood material 6 for joining the upper and lower chord materials and the wood material 6 for the eaves are integrated, and one end of one wood material 6 is fitted and fixed between the end flanges of the upper chord material 3a. An embodiment in which the center of the lower chord 6 is fitted and fixed between the flanges in which the interfering lips at the ends of the lower chord 4 are inserted can also be adopted.

FIG. 10 is a front view showing another embodiment of the steel truss of the present invention. Here, as an example, a case is shown in which the truss span is set to 3.6 m and diagonal members are attached to the truss. The material of the diagonal material is a wooden two-by-four lumber with a cross-sectional outer dimension of 89 mm on a long side and 38 mm on a short side. Both ends of the oblique material are fitted by folding the lip portions that interfere with the inside of the upper chord material 3a or 3b and the inside of the lower chord material 4 into the inside, and are joined by tapping screws 5 and nails 5a.

As shown in FIG. 11, when the wooden member 6 is attached to the center of the truss as a bundle, the overlapping portions are formed without overlapping the flanges of the upper chord members 3a and 3b at the top of the truss. Cut vertically and fit. The lip portion that interferes with the portion is folded inward to fit the wooden material 6, and the tapping screw 5 or the nail 5a
And so on. With this configuration, the truss can be easily configured without using a truss-assembly auxiliary member such as a gusset plate, and the number of parts can be reduced and the construction can be rationalized. Supply becomes possible.

The thickness of the truss members and the size of the truss members described above are not limited to the above, and the truss members can be designed at any time depending on the scale of the building or the load conditions.
It is a desirable form that the construction is easy and the plate thickness of the shaped steel member is about 0.5 mm to 1.6 mm.

[0032]

According to the present invention described above, the following effects can be obtained. By configuring the cross-sectional shape of the steel truss shaped steel member as in claim 1 or 2, the cross-sectional performance of the shaped steel member is improved by the provided lip portion. In addition, since the lip portion can be easily folded inside the flange, at least one of the shaped steel members interferes with each other or when the shaped steel member is joined to a wooden material as described in claim 3 or 4. By folding the lip and overlapping and joining the flanges together, a joint having the following advantages can be formed.

[0033] The truss joints are not cut out or joint parts (such as gusset plates) are not required, so that cost and labor can be reduced. The assembled truss has a box-shaped section at the joint with the wall. There is no need for a cover material for attaching the cover. By making the internal dimensions of the shaped steel member substantially the same as the external dimensions of the wooden material (for example, wooden two-by-four lumber), the wooden material can be used for the diagonal material and the bundle material as a joining member. Since these are fitted in the shaped steel member, the thickness of the assembled truss is reduced to about the thickness of the shaped steel member, and the transport efficiency is improved. Since nails and screws can be driven from both sides of the shaped steel member, the number of nails and screws driven into one surface can be reduced,
It is less likely to interfere with hardware used for joining to the wall, and the workability is improved. It is also possible to implement a form in which a wooden material is fitted into the eaves, which has a great effect of reducing the thermal bridge.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a shaped steel member of the present invention.

FIG. 2 is a front view showing an embodiment of the steel truss of the present invention.

FIG. 3 is a sectional view taken along the line III-III of FIG. 2;

FIG. 4 is an arrow view along the line IV-IV in FIG. 2;

FIG. 5 is a sectional view taken along the line VV in FIG. 2;

FIG. 6 is a front view showing another embodiment of the truss of the present invention.

FIG. 7 is a bottom view of the truss of FIG. 6;

8 is a sectional view taken along the line VIII-VIII in FIG.

FIG. 9 is a front view showing another embodiment of the truss of the present invention.

FIG. 10 is a front view showing another embodiment of the truss of the present invention.

FIG. 11 is a front view showing another embodiment of the truss of the present invention.

[Explanation of symbols]

 Reference Signs List 1 web 2a flange 2b flange 2a 'lip 2b' lip 3a upper chord material 3b upper chord material 4 lower chord material 5 tapping screw 5a nail 6 wood material

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2E125 AA15 AB05 AB10 AB12 AC16 AC23 AG03 AG04 AG51 BE10 CA01 CA14 CA77 CA78 EA00 EA33 2E163 FB32 FB45 FF03 FF08

Claims (4)

[Claims] 1. A cross section is formed into a substantially U-shape by a short side web and a long side flange, and a tip portion of the long side flange is bent inward by 90 ° or more to form a lip portion,
A steel truss shaped steel member having a substantially C-shaped cross section. 2. The steel member for a steel truss according to claim 1, wherein the inner dimension is substantially equal to the outer dimension of the wooden material. 3. When joining the steel truss shaped steel members according to claim 1 or 2 alternately while overlapping the flanges, at least one of the interfering lips is folded in parallel with the flange. Characteristic joint structure of steel truss. 4. At the time of joining a truss member by fitting a wooden member into the steel truss shaped steel member according to claim 2,
A truss joint structure in which a lip is folded in parallel with a flange.