JP2000054491A - Infilled steel pipe concrete column - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infilled steel pipe concrete column of structure sufficiently ensuring tension bearing force without making joint reinforcements continuous with each other. SOLUTION: Steel pipes are connected to the upper and lower sides of a connection part, and concrete 3 is integrally filled in these steel pipes and connection part. Joint reinforcements 4 inserted through the connection part so that both ends are inserted in the upper and lower steel pipes 1 are embedded in the concrete 3. The end inner surfaces of the steel pipes 1 are provided with pressure bearing members 6 protruded inward to be engaged with the concrete 3, and tensile force is transmitted between the steel pipes 1 and the joint reinforcements 4 through the pressure bearing members 6 and concrete 3. A band steel 7, a reinforcement, a weld bead, a baseplate or a rib protruded into the steel pipe 3 can be suitably used as the pressure bearing member 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete column filled with concrete in a steel pipe.

[0002]

2. Description of the Related Art As shown in FIG. 6, a filled steel pipe concrete column has steel pipes 1 connected at the top and bottom of a connection part, and the connection part is connected to the top and bottom steel pipes 1 at the connection part. 2 in which concrete 3 is integrally filled in the series of steel pipes 1 and 2. Then, in order to secure the joint strength between the column and the beam, the joining reinforcing bar 4 is arranged so as to penetrate the connection portion, and both ends thereof are inserted into the upper and lower steel pipes 1 and buried in the concrete 3. It is common to do. Note that a steel beam is generally used as the beam 5, but an RC beam or an SRC beam may be adopted. In such a case, the connection steel pipe 2 may be omitted.

[0003] A concrete-filled steel pipe column having such a structure has an advantage that rebar arrangement work and formwork work related to column construction can be greatly simplified as compared with ordinary RC columns.

[0004]

When a tensile load is applied to a concrete column filled with steel pipe as described above, the upper and lower joint reinforcing bars 4 are connected to each other as shown in FIG. 7 in order to secure a tensile strength. They are made continuous with each other, and a tensile force is applied to the series of joining reinforcing bars 4.

[0005] However, making the reinforcing steel bars 4 continuous over the entire length of the columns as described above is almost the same as providing RC columns in the steel pipe 1, and the advantages of the filled steel pipe concrete columns are lost. Will be. That is, in this case, not only does the amount of rebar increase, but also a joint for joining the rebars 4 and an operation therefor are required, which is a great disadvantage in terms of workability and cost.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a filled steel pipe concrete column having a structure capable of sufficiently securing a tensile strength without connecting reinforcing bars.

[0007]

According to the filled steel pipe concrete column of the present invention, steel pipes are arranged continuously above and below a connection part, concrete is integrally filled in the steel pipe and the connection part, and the connection part is formed. A reinforcing rod for insertion, which is inserted into the upper and lower steel pipes at both ends thereof, is buried in the concrete, and a support rod projecting inward from an inner surface of an end of the steel pipe and engaging with the concrete. A pressure member is provided, and a tensile force is transmitted between the steel pipe and the reinforcing bar through the supporting member and the concrete.

[0008] The supporting member may be an annular steel strip or a reinforcing bar welded along the inner peripheral surface of the end of the steel pipe, a weld bead annularly padded along the inner peripheral surface of the end of the steel pipe, or an end of the steel pipe. An annular base plate welded to the portion, an annular rib formed along at least the inner peripheral surface of the end portion of the steel pipe, or the like can be suitably adopted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the vicinity of a joint portion of a filled steel pipe concrete column according to an embodiment of the present invention. In the pillar of the present embodiment, steel pipes 1 are continuously provided above and below a connection part, and concrete 3 is integrally filled into the steel pipe 1 and the connection steel pipe 2 similarly to the conventional one shown in FIG. In addition, the joining rebar 4 that passes through the connection portion is provided with both ends inserted into the steel pipe 1. In the illustrated example, a steel beam is used as the beam 5, which is joined to the outer peripheral surface of the connection steel pipe 2.

In the column of this embodiment, a supporting member 6 is provided on the inner peripheral surface of the end of the steel pipe 1 so as to protrude inward. That is, the steel strip 1 is welded to the lower end of the steel pipe 1 connected to the upper part of the connection part and the upper end part of the steel pipe 1 connected to the lower part of the connection part so as to form an annular shape over the entire inner peripheral surface of the steel pipe 1. The steel strip 7 functions as a bearing member 6 that engages with the concrete 3 in the steel pipe 1.

In the column of the present embodiment, the provision of such a supporting member 6 enhances the integration of the steel pipe 1 with the concrete 3 inside the steel pipe 1, and as a result, the supporting member 6 and the concrete 3 are separated. The tensile force is reliably transmitted between the steel pipe 1 and the joining rebar 4 via the steel pipe 1 so that an excellent tensile strength can be exhibited.

That is, the tensile strength of this type of filled steel pipe concrete column is determined by
Is determined by the anchoring force of the steel pipe 1 and the adhesive force of the inner surface of the steel pipe 1 to the concrete 3. For the former, a sufficient anchoring force can be naturally secured by appropriately setting the anchoring length of the reinforcing bar 4 for joining. In the latter case, a sufficient adhesive force may not always be able to be secured, and in the past, this has been a bottleneck, and it has been impossible to sufficiently secure the tensile strength of the entire column. For this reason, as shown in FIG. 7, the connecting reinforcing bar 4 is made continuous like a main bar to bear the tensile strength.

On the other hand, in the column of the present embodiment, the steel pipe 1
By providing the bearing member 6 on the inner surface and engaging it with the concrete 3, the steel pipe 1 and the concrete 3 are surely integrated, so that the steel pipe 1 and the reinforcing steel bar 4 overlap with each other via the concrete 3. By forming the joints, they naturally become structurally connected, so that the transmission of tensile force between them can be ensured.

Therefore, in the column of the present embodiment, unlike the conventional one shown in FIG. 7, the connecting reinforcing bars 4 are not continuously connected to each other, so that the advantages of the filled steel pipe concrete column are not impaired. The tensile strength can be greatly improved as compared with those obtained. Of course, the bearing member 6
It is only necessary to weld a simple strip steel 7 having a small cross section to the inner surface of the steel pipe 1, so that the cost increase and the labor for the construction are insignificant. The dimensions of the steel strip 7, particularly the inwardly projecting dimensions, may be appropriately set according to the required tensile strength, and may be provided over two or more at the end of the steel pipe 1 if necessary.

Further, the bearing member 6 is not limited to the strip steel 7 as described above, but may take various forms as listed below, for example. FIG. 2 shows the supporting member 6 formed of two annular reinforcing bars 8 welded to the inner peripheral surface of the steel pipe 1, and FIG. 3 supports a weld bead 9 which has been padded in an annular shape along the inner peripheral surface of the end of the steel pipe 1. FIG. 4 shows an annular base plate 10 welded to the end of the steel pipe 1 as the bearing member 6, and FIG.
Is a steel pipe 1 having a rib 11 at least on an inner peripheral surface of the end (a rib having a rib over the entire length as well as the end) may be used as the bearing member 6. Each of them is a simple configuration and does not require a significant increase in cost, and can reliably transmit a tensile force between the steel pipe 1 and the reinforcing steel bar 4 via the concrete 3.

[0016]

As described above, the concrete-filled steel pipe column of the present invention is provided with a supporting member which protrudes inward on the inner surface of the end of the steel pipe and engages with the concrete, and via the supporting member and the concrete. Since the tensile force is reliably transmitted between the steel pipe and the reinforcing bar for joining, the tensile strength can be naturally improved without the necessity of continuously connecting the reinforcing bar as in the related art. In particular, if a steel strip, a reinforcing steel bar, a weld bead, a base plate, or a rib on the inner surface of a steel pipe is used as the supporting member, the above-described effects can be obtained without any significant cost increase.

[Brief description of the drawings]

FIG. 1 is a view showing a filled steel pipe concrete column according to an embodiment of the present invention.

FIG. 2 is a view showing another example of the supporting member.

FIG. 3 is a view showing still another example of the supporting member.

FIG. 4 is a view showing still another example of the supporting member.

FIG. 5 is a view showing still another example of the supporting member.

FIG. 6 is a view showing a conventional filled steel pipe concrete column.

FIG. 7 is a view showing another example of a conventional filled steel pipe concrete column.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel pipe 3 Concrete 4 Reinforcing bar 6 Bearing member 7 Steel band (bearing member) 8 Reinforcing bar (bearing member) 9 Weld bead (bearing member) 10 Base plate (bearing member) 11 Rib (bearing member)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kentaro Nakagawa 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation F-term (reference) 2E163 FA02 FB06 FB09 FB46 FD36 FD42 FD43 FF17 2E164 AA02 BA02 CA01

Claims (6)

[Claims] 1. A steel pipe is connected above and below a connection part, concrete is integrally filled in the steel pipe and the connection part, and both ends are inserted into the upper and lower steel pipes through the connection part. A filled steel pipe concrete column in which the joined reinforcing steel is buried in the concrete, and a supporting member is provided on an inner surface of an end portion of the steel pipe so as to project inward and engage with the concrete, and the supporting member and A concrete column filled with steel pipe, wherein a tensile force is transmitted between the steel pipe and the reinforcing steel bar through the concrete. 2. The concrete column as set forth in claim 1, wherein the bearing member is an annular steel strip welded along an inner peripheral surface of an end of the steel pipe. 3. The concrete column as set forth in claim 1, wherein said bearing member is an annular reinforcing bar welded along an inner peripheral surface of an end portion of said steel pipe. 4. The concrete column as set forth in claim 1, wherein said bearing member is a weld bead which is annularly padded along an inner peripheral surface of an end portion of said steel pipe. 5. The concrete column according to claim 1, wherein the bearing member is an annular base plate welded to an end of the steel pipe. 6. The concrete column as set forth in claim 1, wherein said bearing member is an annular rib formed at least along an inner peripheral surface of an end of said steel pipe.