JPH1122024A - Buckling stiffening members - Google Patents

Abstract

(57) [Problem] To provide a buckling stiffening member that is easy to manufacture a joint, easy to connect to other members, and does not cause local deformation. SOLUTION: When a flat steel 2 which is an axial force member is inserted along a diagonal line of a stiffening pipe 1 into a stiffening pipe 1 made of a rectangular steel pipe with a gap provided, and a compressive force acts on the flat steel 2 A buckling stiffening member in which the flat steel 2 bends in the direction perpendicular to the plate surface and buckles at the corners of the stiffening tube 1; A buckling stiffening member having a width that allows two joint plates 3 to be fixed to a plate surface and that can be inserted into the stiffening tube 1 with the joint plate 3 fixed to at least one of the ends.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buckling stiffener which is hardly buckled even when subjected to a large compressive force among members used for braces and truss members applied to a building frame structure. Placing flat steel as an axial force member along a diagonal line of a rectangular steel pipe on a member, especially a stiffened pipe made of a rectangular steel pipe, and buckling the flat steel when compressive force acts on the flat steel And a buckling stiffening member restrained at a corner of the buckling member.

[0002]

2. Description of the Related Art Japanese Patent Application No. 8-328635 discloses a buckling stiffening member in which a flat steel as an axial force member is arranged along a diagonal line of a square steel pipe on a conventional stiffening pipe made of a square steel pipe. Buckled stiffening members. This buckling stiffening member inserts a flat steel, which is an axial force member, in a diagonal arrangement with a gap in a stiffening pipe made of a square steel pipe, and when a flat steel is subjected to compressive force, The flexure in the direction perpendicular to the plate surface and buckling are restrained by the corners of the stiffening tube. A brazing material in which cross-shaped joint members are fixed at different angles.

[0003] The reason why the joint member having a cross-shaped cross section is fixed to both ends of the flat steel as the axial force member is that simply providing bolt holes at both ends of the flat steel to form a joint results in a bolt hole. This is because the cross-sectional area of the joint portion with the gap becomes insufficient as the axial force member.

[0004]

However, the joint structure of the buckling stiffening member described in Japanese Patent Application No. 8-328635 has the following problems.

To fix the cross-shaped joint member to the end of the flat steel, a slit-shaped groove is provided at the center in the width direction of the flat steel end, and the cross-shaped joint member is inserted into this groove.
The cross face of the joint member is 45 with respect to the flat steel plate surface (width direction).
°, the flat bar and the joint member are welded, so that it takes a lot of time to construct the joint.

Further, since the joint member has a cross-shaped cross section,
It is difficult to connect the joint member in advance to the flat steel as the axial force member and insert it into the square steel pipe as the stiffening pipe, which is not easy to assemble.

Further, the connection of the beams and columns to the gusset plate is not easy, and joining parts such as splice plates are required.

Further, at both ends near the joint of the axial force member, the stiffening tube is eliminated, so that the restraining effect of the stiffening tube is poor, and the end face of the stiffening tube is easily deformed by the restraining reaction force. In addition, since it is inevitable that the buckling stiffening member and the frame of the building are not completely pin-jointed or eccentrically joined, a slight bending moment acts on the buckling stiffening member, and The force material is locally plasticized and buckling easily occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, in which a joint can be easily manufactured, and a beam or a column can be easily connected to a gusset plate. An object of the present invention is to provide a buckling stiffening member in which local deformation does not occur in an axial force member or a stiffening tube.

[0010]

A buckling stiffening member according to the present invention is provided by inserting a flat steel, which is an axial force member, into a stiffening pipe made of a rectangular steel pipe along a diagonal line of the stiffening pipe. And a buckling stiffening member configured to restrain the flat steel from bending and buckling at the corners of the stiffening tube when a compressive force acts on the flat steel. Two joint plates are fixed to both plate surfaces at both ends in the longitudinal direction of the steel, and the joint plate fixed to at least one of the ends has a width capable of being inserted into the stiffening tube.

In the flat steel, the width direction of the flat steel is located on the diagonal line of the stiffening pipe, and there is a slight gap between the widthwise end of the flat steel and the corner of the stiffening pipe. It is inserted into the stiffening tube.
Then, two joint plates are joined to both plate surfaces at both ends in the longitudinal direction of the flat steel by fillet welding.

The width of the joint plate joined to at least one of the two ends is a width that can be inserted into the stiffening tube.

[0013] The joint plate is provided with a plurality of bolt holes for joining, and the total cross-sectional area of the two joint plates after drilling the bolt holes is such that the joint plate has the same strength as the flat steel. if there is,
The cross-sectional area should be equal to or larger than the cross-sectional area of the flat steel.

Since the buckling stiffening member is constructed as described above, a joint having sufficient joint strength can be easily manufactured, and a gusset plate of a beam or a column is provided between two joint plates. Can be connected by sandwiching
Easy connection.

Furthermore, since the joint plate joined to at least one of both ends of the flat steel can be inserted into the stiffening tube, the joint plate is connected to the flat steel in advance,
Since such a state can be inserted into the stiffening tube, assembly of the stiffening member is easy.

Further, a part of the joint plate enters into the stiffening tube, and both ends in the width direction of the joint plate are almost in contact with the inner surface of the stiffening tube.

Even if the flat steel expands and contracts, a part of the joint plate is inserted into the stiffening tube, and both ends in the width direction of the joint plate are almost in contact with the inner surface of the stiffening tube. The reason for this is that if both ends in the width direction of the joint plate are completely in contact with the inner surface of the stiffening tube, resistance will be generated due to the contact, and the axial force will flow to the stiffening tube and the stiffening tube will This is because there is a risk of deformation, and the stiffening tube only plays a role of restraining the buckling deformation of the axial force member while maintaining a substantially contact state.

By thus allowing a part of the joint plate to enter the stiffening pipe, the joint plate can also serve as a reinforcing member for the flat steel at both ends in the longitudinal direction of the flat steel. In addition, it is possible to prevent the flat steel from being locally deformed at the end of the stiffening pipe and the corner of the stiffening pipe from being deformed.

Further, the axial force member is an extremely low yield point steel,
The joint plate is made of ordinary steel.

With this configuration, it is possible to improve the earthquake resistance during an earthquake and to obtain a sufficient joint strength.

[0021]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1A is a front view of a buckling stiffening member according to a first embodiment of the present invention, and FIG.
FIG. 1C is a sectional view taken along the line AA of FIG.

The buckling stiffening member comprises a square steel pipe 1 as a stiffening pipe, and a rectangular steel pipe 1 having a width in the plate width direction on the inner surface of the square steel pipe 1.
A flat steel 2 as an axial force member inserted so as to face the diagonal line of the flat steel 2 and a joint plate having a width fixed to both plate surfaces at both ends in the longitudinal direction of the flat steel 2 and having a width capable of being inserted into the rectangular steel pipe 1. And 3.

When a compressive force acts on the flat bar 2, the flat bar 2 bends in the direction perpendicular to the plate surface and attempts to buckle. Steel pipe 1
Corner portions are restrained, and buckling can be prevented. The compressive force acting on the flat steel 2 as the axial force material is applied between the flat width direction end 2 a of the flat steel 2 and the corner of the square steel pipe 1.
Is provided so as not to flow into
Is about 1/20 to 1/40 of the thickness of the flat steel 2.

The joint plate 3 is joined to the flat steel 2 by fillet welding 4. The joint plate 3 is provided with a bolt hole 5 at a portion protruding from the end of the flat steel 2 for joining to a gusset plate of a column or a beam, and the gusset plate is inserted between the two joint plates 3. By pinching and tightening the bolt through the bolt hole 5 and the bolt hole provided in the gusset plate, it is possible to easily join.

The buckling stiffening member can be easily joined to the joint plate 3 by the fillet weld 4 and can be formed with a bolt hole 5 in the joint plate 3 by appropriately selecting the thickness of the joint plate 3. , A sufficient sectional area with respect to the axial force can be secured.

Further, since connection can be made by sandwiching a gusset plate of a beam or a column between the two joint plates 3, the connection can be made easily.

Further, the joint plate 3 to be joined to at least one of both ends in the longitudinal direction of the flat steel 2 has a width capable of being inserted into the rectangular steel pipe 1, and the joint plate 3 is previously formed on the flat steel 2. The stiffening member can be easily assembled by connecting and inserting such a state into the square steel pipe 1.

FIG. 2 (a) is a partial front view of a buckling stiffening member according to a second embodiment of the present invention, and FIG. 2 (b) is FIG. 2 (a).
FIG.

In this buckling stiffening member, the square steel pipe 1
The flat steel 2 and the flat steel 2 are the same as the buckling stiffening member of the first embodiment, but a part 3a of the joint plate 3 enters the rectangular steel pipe 1 and the plate 3a of the joint plate 3 Both ends 3b in the width direction are
It is almost in contact with the inner surface of the rectangular steel pipe 1. In such a state, a part 3a of the joint plate 3 can serve as a reinforcing material for the flat steel 2 at both ends of the rectangular steel pipe 1, and the flat steel 2 and the rectangular steel pipe 1 are in the vicinity of the ends. Thus, local deformation can be prevented.

As shown in FIG. 3, a chamfered portion 3c may be provided at the end 3b in the width direction of the joint plate 3 shown in FIG. By providing such a chamfered portion 3c, the ratio of the portion substantially in contact with the inner surface of the square steel pipe 1 at the both ends 3b in the width direction of the joint plate 3 becomes larger than that without the chamfered portion 3c, so that no chamfering is performed. More specifically, it is possible to prevent the flat steel 2 from being locally deformed at the end of the rectangular steel pipe 1 and to prevent the corner portion of the rectangular steel pipe 1 from being deformed.

Further, since the joint plate 3 having a wider width can be used by chamfering, the joint strength can be improved.

In each of the buckling stiffening members of the first embodiment and the second embodiment, the flat steel 2 is made of extremely low yield point steel and the joint plate 3 is made of ordinary steel. ,
Earthquake resistance during an earthquake can be improved.

[0034]

According to the present invention, the joint can be easily manufactured, the stiffening member can be easily assembled, and the connection of the beam and the column to the gusset plate can be simplified. A buckling stiffening member in which local deformation does not occur can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a buckling stiffening member according to a first embodiment, where (a) is a front view, (b) is a side view, and (c) is (a).
It is AA sectional drawing of.

FIGS. 2A and 2B are explanatory views of a buckling stiffening member according to a second embodiment, wherein FIG. 2A is a partial front view, and FIG. 2B is a cross-sectional view taken along line BB of FIG.

FIG. 3 is a cross-sectional view of a buckling stiffening member according to a second embodiment when a joint is chamfered.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Square steel pipe 2 Flat steel 2a Both ends in the width direction of flat steel 3 Joint plate 3a Square steel tube insertion part of joint plate 3b Width end of joint plate 3c Chamfered joint plate 4 Fillet weld 5 Joint bolt hole 5

Claims (3)

[Claims] 1. A flat steel, which is an axial force member, is inserted along a diagonal line of a stiffening pipe into a stiffening pipe made of a square steel pipe with a gap provided therebetween.
When a compressive force is applied to the flat steel, the flat steel bends in a direction perpendicular to the plate surface, and the buckling stiffening member is configured to restrain buckling at the corners of the stiffening tube. Two joint plates are fixed to both plate surfaces at both ends in the longitudinal direction, and the joint plate fixed to at least one of the ends has a width capable of being inserted into the stiffening tube. Buckling stiffening member. 2. The buckling according to claim 1, wherein a part of the joint plate enters into the stiffening tube, and both ends in the width direction of the joint plate substantially contact the inner surface of the stiffening tube. Stiffening members. 3. The buckling stiffening member according to claim 2, wherein the axial force member is extremely low yield point steel, and the joint plate is ordinary steel.