JPH0988236A - Steel-pipe column-column beam connection structure and manufacture of steel-pipe column thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower a thickness increasing magnification, to improve productive efficiency while ensuring the strength of a beam connection section, and to reduce cost. SOLUTION: A steel pipe 3 for reinforcement is installed concentrically to a part in the longitudinal direction of a steel pipe 2 as the chief material of a column 1, and a thickness increasing section 2a, in which a pipe wall is increased by plastic deformation, is formed to the steel pipe 2 as the chielf material under a stuck state with the steel pipe 3 for reinforcement. The thickness increasing section 2a can be formed by applying compressive force in the axial direction while being heated by high-frequency induction heating. A beam 4 is joined with a beam connection section A formed of the thickness increasing section 2 and the steel pipe 3 for reinforcement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel pipe column-column beam joint structure in which a beam joint is reinforced by thickening and the like, and a method for manufacturing the steel pipe column.

[0002]

2. Description of the Related Art Conventionally, when a beam is joined to a round or square steel pipe column, in order to secure strength, two diaphragms 103 are generally welded to the steel pipe column 101 as shown in FIG. It is a part. The upper and lower flanges of the beam 102 are welded to the diaphragm 103. Diaphragm 103
The steel pipe pillar 101 is cut into upper and lower pillars 101a and 101b and an intermediate pillar 101c, and welded in a sandwiched state at the cut positions. However, cutting the steel pipe column 101 and welding the diaphragm 103 in this way requires a lot of processing man-hours and requires a high welding technique, resulting in a high cost. For this reason, various proposals have been made such that a joint box made of cast steel or the like is interposed in a steel pipe column, and a beam is bolted to the joint box. However, since cast steel has a high material cost, both are costly column-beam joints. It becomes a structure.

In order to solve such a problem, the applicant of the present invention, as shown in FIG.
No. 04 is provided and the beam 102 is joined to the thickened portion 104 with a bolt or the like (for example, Japanese Patent Application No. 6-33619).
No. 6). The thickened portion 104 is integrally formed by plastically deforming by applying a compressive force in the axial direction while heating the steel pipe as a material by high frequency induction heating. As described above, with the configuration in which the thickened portion 104 is provided on the steel pipe column 101, mass production can be performed at the steel pipe supplier, and the construction company does not need to perform complicated processing on the material, which shortens the construction period. Can be achieved.

[0004]

However, the thickened portion 104
In the case of the material steel pipe having a small wall thickness, a high technology is required for the formation, and the cost becomes high. Further, there is a limit to the wall thickness increasing ratio of the pipe wall, and the wall thickness increasing portion 1 having a sufficient thickness for the required yield strength.
There are cases where 04 is not obtained. Further, if the thickness increase ratio is increased, it takes time to form the thickness increase portion 104, and the productivity deteriorates. This invention solves the above-mentioned problems, and improves the production efficiency while securing the strength of the beam joint portion, and a cost-reduced steel pipe column-column beam joint structure and a method for manufacturing the steel pipe column. The purpose is to provide.

[0005]

A steel pipe column according to the present invention is provided with a reinforcing steel pipe concentric with a part of a steel pipe as a main material of the column in a longitudinal direction, and the main material steel pipe is plastically deformed to form a pipe wall. The thickened portion having the increased thickness is provided in close contact with the reinforcing steel pipe. The reinforcing steel pipe may be provided on the outer peripheral side or the inner peripheral side of the main material steel pipe. By using the reinforcing steel pipe in this way, it is possible to form the beam joint portion having a satisfactory thickness while suppressing the thickness increase ratio to be low. The reinforcing steel pipe is integrated with the main material steel pipe by a frictional force or the like by closely contacting with the main material steel pipe in the process of forming the thickened portion. Therefore, the work of joining the reinforcing steel pipe to the main material steel pipe is not particularly necessary. When the reinforcing steel pipe is provided on the outer circumference of the main material steel pipe, the outer dimension required for accuracy as the beam joint is determined by the outer dimension of the reinforcing steel pipe, so high precision is required for adjusting the amount of plastic deformation of the thickened portion. Outer dimensions are uniform at each axial location without the need for or high control. The thickened portion may be integrally provided at both ends with a bulge portion that engages with the end surface of the reinforcing steel pipe. When the bulge portion is provided in this way, in addition to the frictional force of the contact surface between the main material steel pipe and the reinforcing steel pipe, support by the bulge portion is obtained, and the force transmission from the beam to the main material steel pipe is ensured.

The column-beam joint structure of the present invention uses the steel pipe column of the present invention, and includes a high-strength bolt or a one-side bolt inserted through the thickened portion of the main material steel pipe and the reinforcing steel pipe. The steel beam is joined to the steel pipe column by the axial fastener. Since the axial fastener is inserted over the main material steel pipe and the reinforcing steel pipe, the force is reliably transmitted from the beam to the main material steel pipe of the column. In the method for manufacturing a steel pipe column according to the present invention, the main material steel pipe is inserted into a reinforcing steel pipe having a length dimension of a part of the main steel pipe. In this inserted main material steel pipe, a thickened portion that is in close contact with the reinforcing steel pipe is formed by plastic deformation of the pipe wall. The thickening portion may be formed by plastic deformation by applying a compressive force in the axial direction to the main material steel pipe while high-frequency induction heating the main material steel pipe.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1 (A), this steel pipe column 1 is prepared by passing a reinforcing steel pipe 3 having a necessary thickness on the outside of a steel pipe 2 which is a main material of the column.
As shown in (B), the main material steel pipe 2 is provided with a thickened portion 2a in which the pipe wall is thickened by plastic deformation in close contact with the reinforcing steel pipe 3. This thickening is performed, for example, while heating the portion of the main steel pipe 2 to be plastically deformed by high frequency induction heating,
It can be formed by applying a compressive force in the axial direction to the main material steel pipe 2. The heating of the main material steel pipe 2 is easy if the heating portions are gradually shifted in the axial direction so as to perform the heating in part of the length range to be the thickened portion 2a.

The main material steel pipe 2 and the reinforcing steel pipe 3 are shown in FIG.
A round steel pipe may be used as shown in FIG.
It is also possible to use a rectangular steel pipe as in. The reinforcing steel pipe 3 has a length required for reinforcement as a beam joint of the steel pipe column 1.
The thickened portion 2a swells on both sides of the outer surface and the inner surface of the main material steel pipe 2, but it may swell only on the outer surface side. Further, in this example, bulging portions 2b, 2b that engage with the end surface of the reinforcing steel pipe 3 are integrally provided at both ends of the thickened portion 2a. This bulge portion 2b is formed in the process of thickening. The bulge portion 2b does not necessarily have to be provided.

FIG. 1C shows a beam-column joint structure using the thickened steel pipe column 1. The beam 4 is made of a steel frame beam such as H-section steel, and its upper and lower flanges 4a are connected to a thickened portion 2a of the thickened steel pipe column 1 through a T-shaped jointed article 5 made of a split tee.
It is joined to. When the thickened steel pipe column 1 has a round shape, the T-shaped joint metal 5 has a head piece 5b as shown in FIG. 2 (A).
Is curved in an arc shape along the outer diameter surface of the reinforcing steel pipe 3. The T-shaped joining hardware 5 has its leg pieces 5a placed on the flange 4a of the beam 4 and joined by bolts 6 such as high-strength bolts.
Moreover, the head piece 5b is joined by the joining hole 7 penetrating the thickened portion 2a and the reinforcing steel pipe 3 and the axial fastener 8 inserted through the hole of the head piece 5b.

In this example, a one-side bolt is used as the shaft-shaped tightening tool 8. Therefore, it is not necessary to screw the joining hole 7 of the thickened portion 2a, and the steel pipe column 1 with a closed cross section is used.
For tightening, you can only insert and tighten from the outside. The "one-side bolt" referred to in this specification is a general term for axial fasteners whose head is formed by plastic deformation at the other end by operation from one end to enable tightening, and when called a brand bolt There is also. As shown in FIG. 3, the joining hole provided in the thickened portion of the thickened steel pipe column 1 may be a screw hole 7A, and the beam 4 may be joined with a bolt such as a normal high-strength bolt. Further, as shown in FIG. 4, the beam 4 is assumed to have an end plate 4a, and the end plate 4a is attached to the steel pipe for reinforcing the thickened steel pipe column 1 with a shaft-shaped fastener 8 such as a one-side bolt or a high-strength bolt. You may join to the outer surface of 3.

According to the thickened steel pipe column 1 having this structure, the reinforcing steel pipe 3 having a required thickness is prepared in advance, and the thickened portion 2a is formed inside the reinforcing steel pipe 3. When the mouth portion A is obtained, the thickness increasing ratio is smaller than that in the case where only the thickness increasing portion is dealt with. Therefore, the production efficiency is good, and the outer dimension of the beam joint portion A can be obtained with high accuracy without requiring high-level control. The reinforcing steel pipe 3 has a thickened portion 2a.
By being in close contact with the main material steel pipe 2 during the formation process, the main material steel pipe 2 is integrated with the friction material or the like. Therefore, it is not necessary to separately join the reinforcing steel pipe 3 and the main material steel pipe 2.
When the bulge portions 2b that engage with the end portions of the reinforcing steel pipe 3 are formed at both ends of the thickened portion 2a, the reinforcing steel pipe 3
The axial force acting on not only the frictional force between the main material steel pipe 2 but also the bulging portion 2b is received. Therefore, the force can be smoothly and reliably transmitted from the beam 4 to the main material steel pipe 2, and the reinforcing steel pipe 3 is not likely to be displaced. The beam 4 may be joined to the reinforcing steel pipe 3 by welding, but when the beam 4 is joined with the axial fastener 8 penetrating to the main material steel pipe 2 as in the example of FIGS. 1 to 3, the main material steel pipe is used. Since the frictional force between the steel pipe 2 and the reinforcing steel pipe 3 is increased, more firm joining can be performed.

FIG. 5 shows a steel-framed reinforced concrete column in which the thickened steel pipe column 1 is filled with concrete 9 and the reinforcing bars 10 are embedded in the concrete 9 in the example of FIG. 1 (C). By providing the concrete 9 or the like in this way, the proof stress of the column is strengthened. The reinforcing bar 10 may be omitted.

FIG. 6 shows an example of a steel frame structure to which the thickened steel pipe column 1 and the beam-column joint structure are applied. In this example, a plurality of thickened steel pipe columns 1 are vertically joined by a column joint 11, and each thickened steel pipe column 1 has a plurality of beam joints A for respectively joining the beams 4 of each layer. It is as a thing. For each of the beam joints A, the beam joints shown in FIG. 1 (C), FIG. 4 and the like are used. The lower end of the thickened steel pipe column 1 at the lowermost stage is fixed to the foundation 12 together with the base metal piece 13. The column joint 11 is provided with a thick-walled strengthened portion 2c including a reinforcing steel pipe and a wall-thickened portion similarly to the beam joint portion A, except that it is formed at the end of the wall-thickened steel pipe column 1, and a splint plate 16 is attached and joined by a shaft-shaped fastener such as a one-side bolt or a normal high-strength bolt. Since the column joint 11 has a small moment load when it comes to the center between the layers, the column joint 11 may be joined with the normal pipe thickness without providing the thick-walled reinforcing portion 2c.

FIG. 7 shows another embodiment of the present invention.
In this example, the reinforcing steel pipe 3A is arranged inside the main material steel pipe 2, and the reinforcing steel pipe 3A and the main material steel pipe 2 are integrated by the thickened portion 2a in which the main material steel pipe 2 is thickened in and out. . The thickened portion 2a is used as the beam connection portion A, and the beam 4 is joined as in the example of FIG. That is, the shaft-shaped fastener 8 such as a one-side bolt is inserted into the joint hole penetrating the thickened portion 2a and the reinforcing steel pipe 3.
The T-shaped metal fitting 5 is bonded with. Instead of the T-shaped joining hardware 5, an end plate may be provided on the beam 4 to join the thickened steel pipe column 1. Even when the reinforcing steel pipe 3A is provided inside the thickened steel pipe column 1 as described above, a thick and solid beam joint can be obtained with a small thickening ratio.

[0015]

According to the steel pipe column of the present invention, a reinforcing steel pipe is concentrically provided in a part of the longitudinal direction of the steel pipe which is a main material of the column, and the main material steel pipe is thickened to increase the wall thickness by plastic deformation. Since the thickened portion is provided in close contact with the reinforcing steel pipe, it is possible to reduce the thickening ratio while ensuring the strength of the beam joint portion, improving production efficiency and lowering costs. Can be achieved. When the reinforcing steel pipe is provided on the outer circumference, the outer dimensions are made uniform. If bulges that engage the end faces of the reinforcing steel pipes are provided at both ends of the thickened portion, in addition to the frictional force of both steel pipes, the bulges can support the transmission of the force from the beam to the main steel pipe of the column. Will be smooth and reliable. The beam-column joint structure of the present invention is a beam-column joint structure using the steel pipe column of the present invention,
Since the axial fastener is inserted over the main material steel pipe and the reinforcing steel pipe, the force is reliably transmitted from the beam to the main material steel pipe of the column. The method for manufacturing a steel pipe column according to the present invention includes a step of inserting the main material steel pipe into a reinforcing steel pipe having a length of a part of the main steel pipe, and a step of inserting the main material steel pipe inserted into the reinforcing pipe. Since the method includes a step of forming the thickened portion that is in close contact with the steel pipe by plastic deformation of the pipe wall, simple thickening processing is sufficient and productivity is good. In particular, high-frequency induction heating facilitates localized heating, and the thickened portion can be formed more easily and accurately.

[Brief description of drawings]

1A and 1B are explanatory views of a manufacturing process of a thickened steel pipe column according to a first embodiment of the present invention, and FIG. 1C is a beam-column joint structure using the thickened steel pipe column. FIG.

FIG. 2A is a horizontal cross-sectional view of the same beam-column joint structure, and FIG.
[Fig. 6] is a horizontal sectional view of the modification.

FIG. 3 is a partial cross-sectional view of a thickened steel pipe column according to another embodiment of the present invention.

FIG. 4 is a cutaway side view of a beam-column joint structure according to still another embodiment of the present invention.

FIG. 5 is a cutaway side view of a beam-column joint structure according to still another embodiment of the present invention.

FIG. 6 is a side view of a steel frame structure to which the beam-column joint structure is applied.

7 (A) and 7 (B) are explanatory views of a manufacturing process of a thickened steel pipe column according to still another embodiment of the present invention, and FIG. 7 (C) is a beam-column joint structure using the thickened steel pipe column. FIG.

FIG. 8 is a side view of a conventional example.

FIG. 9 is a cutaway side view of another conventional example.

[Explanation of symbols]

1 ... Thickened steel pipe column, 2 ... Main material steel pipe, 2a ... Thickened portion, 2b ...
Bulging part, 3, 3A ... Reinforcing steel pipe, 4 ... Beam, 5 ... Joining metal, 8 ... Axial fastener

Claims (6)

[Claims] 1. A reinforcing steel pipe is concentrically provided in a part of a steel pipe as a main material of a pillar in a longitudinal direction, and the thickened portion in which the pipe wall is thickened by plastic deformation is reinforced in the main steel pipe. A steel pipe column installed in close contact with a steel pipe. 2. The steel pipe column according to claim 1, wherein the reinforcing steel pipe is provided on the outer peripheral side of the main material steel pipe. 3. The steel pipe column according to claim 1, wherein a bulge portion that engages with an end surface of the reinforcing steel pipe is integrally provided at both ends of the thickened portion. 4. A beam-column joint structure using the steel pipe column according to claim 1 or 2, wherein the high-strength bolt or one side is inserted through the thickened portion of the main material steel pipe and the reinforcing steel pipe. A beam-column joint structure in which a steel frame beam is joined to the steel pipe column by an axial fastener such as a bolt. 5. A process of inserting the main material steel pipe into a reinforcing steel pipe having a length of a part of the steel pipe to be the main material, and a process of inserting the main material steel pipe inserted into the reinforcing steel pipe into close contact with the reinforcing steel pipe. The meat part,
A method for manufacturing a steel pipe column including a process of forming the pipe wall by plastic deformation. 6. The method of manufacturing a steel pipe column according to claim 5, wherein the thickened portion due to the plastic deformation is formed by applying an axial compressive force to the main material steel pipe while high-frequency induction heating the main material steel pipe. .