JPH0617613B2 - Filled cylindrical concrete column - Google Patents

Description

TECHNICAL FIELD The present invention relates to a filled cylindrical concrete structure used for, for example, a pillar of a building structure.

[Conventional technology]

BACKGROUND ART Conventionally, as a structure used for a pillar or the like of a building structure, a filled steel pipe concrete structure is known in which a steel pipe that is a formwork is installed vertically and concrete is placed therein.

Since this filled steel pipe concrete structure is simply filled with concrete in the steel pipe, the steel pipe and the concrete are in a bonded state, and they are integrated with each other.

[Problems to be solved by the invention]

However, in the above-described conventional filled steel pipe concrete structure, the steel pipe and the concrete are in an adhered state and are integrated. Therefore, when an axial compressive force acts on this filled steel pipe concrete structure, the steel pipe behaves integrally with the concrete. Further, when the concrete exceeds the predetermined compressive strength, the degree of distortion becomes extremely large. When the concrete is greatly distorted, the steel pipe integrated with the concrete exceeds the yield condition of Mises and local buckling occurs.

Therefore, it cannot be fully expected that the filled steel pipe concrete structure will increase the yield strength of the concrete due to the conforming effect brought about by the steel pipe, and thus it is inevitably a column having a larger cross-sectional area than necessary.

The present invention has been made in view of the above circumstances, and it is possible to sufficiently ensure the increase in the axial compressive strength brought about by the filled concrete structure and to make the cross-sectional area of the column smaller than the conventional one. It is intended to provide filled concrete columns.

[Means for solving problems]

The present invention is a concrete column in which a cylindrical frame body is filled with concrete, wherein the frame body is formed of a thin film and is capable of expanding and contracting in the axial direction thereof, and a cylinder enclosed in the cylinder body. It is characterized by having a reinforcing bar extending in the circumferential direction of the body and surrounding concrete.

According to the present invention, when reinforcing bars are arranged in the concrete to be filled in the frame or when prestress is introduced, the member proof stress can be increased.

[Work]

According to this invention, the cylindrical body can be expanded and contracted in the axial direction by the above-described structure, and the reinforcing bars included in the cylindrical body are also provided so as to surround the concrete, so that in the axial direction. It can be freely moved or transformed. Therefore, when the compressive force in the axial direction acts on the filled concrete structure and the concrete is compressed and it exceeds the prescribed compressive strength and a large strain occurs in the concrete, the frame body follows it and becomes free in the axial direction. In addition to the deformation of the concrete, the reinforcing bars therein try to prevent the deformation of the concrete in the circumferential direction by the tensile stress generated in the axial direction of the reinforcing bar against the deformation of the concrete in the circumferential direction.

That is, the axial force is applied to the concrete,
The frame receives tensile force from the concrete as a reaction that gives the concrete a conforming effect.

〔Example〕

The present invention will be described below with reference to FIGS. 1 to 8. 1 and 2 are views showing a first embodiment of the present invention, which shows a concrete structure having a filled cylindrical body. FIGS. 3 and 4 are views showing a second embodiment of the present invention, FIGS. 5 and 6 are views showing a third embodiment of the present invention, and FIGS. The figure shows the fourth embodiment of the present invention.

First, referring to FIG. 1 and FIG. 2, reference numeral A indicates a column (hereinafter, abbreviated as a column) of a filled cylindrical concrete structure. This pillar A is composed of a frame body 1 and concrete 3 filled in the frame body 1. A cylindrical space portion 4 is formed at the end of the frame body 1. Further, the frame body 1 includes a cylindrical body 1a,
The cylindrical body 1a includes a reinforcing bar 1b which is included in the cylindrical body 1a and spirally wound along the side surface thereof.

Here, the cylindrical body 1a has a tubular shape formed of a thin film such as plastic, and is expandable and contractable in the axial direction.
The reinforcing bars 1b are included in a spiral shape along the side surface of the cylindrical body 1a and surround the concrete 3. Further, since the iron 1b is included in the cylindrical body 1a in a spiral shape, it can be freely deformed in the axial direction of the frame body 1.
The cylindrical space 4 formed at the end of the pillar A is for grouting mortar into the pillar A when the pillar A is connected to another pillar (not shown).

In order to manufacture the pillar A, first, the frame body 1 which is a mold is extended in the axial direction and cut into a predetermined length. Next, concrete 3 is filled into the frame body 1 cut into a predetermined length.
At this time, the space part 4 for grout at the time of connecting another pillar is formed at the end of the pillar A.

In the pillar A manufactured in this way, since the frame body 1 can freely expand and contract in the axial direction, even if a large compressive force is generated in the concrete 3 due to the axial compressive force acting on the pillar A, Frame 1
Will only shrink freely in the axial direction. However, the cylindrical body 1a
Reinforcing bar 1b included in 1 blocks the deformation of concrete 3 in the circumferential direction by the tensile stress generated in the axial direction of reinforcing bar 1b.

Therefore, the frame 1 receives almost no axial compressive force and gives the concrete 3 a conforming effect.
As a reaction that gives the concrete 3 a conforming effect, the reinforcing bar 1b receives a tensile force from the concrete 3 in the axial direction of the reinforcing bar 1b. The pillar A receives an axial force by the concrete 3 which is strong against compression, and a tensile force by the reinforcing bar 1b which is strong against tension.

Therefore, the column A will surely ensure a much higher axial compression strength than the conventional one due to the synergistic effect of the frame 1 and the concrete 3, and the cross-sectional area thereof can be reduced. Becomes

Next, FIGS. 3 and 4 will be described. 3 and 4
In the figure, the same components as those shown in FIGS. 1 and 2 are designated by the same reference numerals. In FIGS. 3 and 4, reference numeral B is a column (hereinafter abbreviated as a column) of a filled cylindrical concrete structure in which reinforced concrete is contained, and reference numeral 5 is a reinforcing bar. Reinforcing bars 5, 5, ... Are reinforced inside the frame 1 along the circumferential direction before the concrete 3 is filled in the frame 1. Concrete 3 is filled into the frame body 1 in which the reinforcing bars 5, 5 ... Therefore, the pillar B can have a higher member yield strength than the pillar A.

Further, FIGS. 5 and 6 will be described. 5 and 6, the same elements as those shown in FIGS. 3 and 4 are designated by the same reference numerals. 5 and 6
In the figure, reference numeral C is a pillar (hereinafter abbreviated as a pillar) of a filled cylindrical concrete structure in which prestressed concrete is contained, and reference numeral 6 is a sheath tube.

In order to manufacture the pillar C, the sheath pipes 6, 6 ... Simultaneously are arranged in the frame body 1 at the same time as the reinforcing bars 5, 5 ... Before the concrete 3 is filled in the frame body 1. The concrete body 3 is filled into the frame body 1 in which the reinforcing bars 5, 5 ... And the sheath tubes 6, 6 ... Are arranged and hardened. Next, a PC steel material (not shown) is passed through the sheath tubes 6, 6 ... Embedded in concrete. After the concrete 3 is hardened, a compression force in the axial direction is introduced into the column C by applying tension to the PC steel material passed through. The column C into which the axial compressive force is introduced has a filled cylindrical concrete structure to which a prestressing force acts.

Therefore, when a tensile force acts on the pillar C, the tensile stress actually generated is a value obtained by subtracting the compressive stress component of the prestress. That is, the pillar C can be a filled cylindrical concrete structure having a higher member proof strength than the pillars A and B.

Next, FIGS. 7 and 8 will be described. In FIGS. 7 and 8, the same components as those shown in FIGS. 1 and 2 are designated by the same reference numerals. In FIGS. 7 and 8, the symbol D indicates a pillar (hereinafter abbreviated as a pillar) of the filled cylindrical concrete structure. In this pillar D, in the frame body 1 which is a form, annular reinforcing bars 1c are arranged at equal intervals in the axial direction.
1c ... is included. Therefore, in this pillar D, the frame 1 is free to expand and contract in the axial direction, and has the same action and effect as the pillar A described above. In addition, this pillar D, by arranging reinforcing bars inside it, or by introducing prestress,
It has the same operation and effect as the pillars B and C described above.

As described above, in each of the above-described embodiments, the frame body 1 is expandable and contractible in the axial direction. Therefore, before use, the frame body 1 can be stored and transported in the axially compressed and folded state. Further, at the time of use, the frame body 1 is stretched if necessary, and can be cut into an arbitrary length for use. The frame body 1 can freely select the axial spacing of the reinforcing bars from a sparse state to a dense state, and its strength can be freely changed according to the usage state of the column.

Further, in each of the above embodiments, the column of the filled concrete structure can be used as the column of the flexible structure because its cross-sectional area can be reduced.

Its application range is considered to be flexible high-rise building. This has the same effect on earthquakes as conventional columns.

〔The invention's effect〕

As described above, according to the present invention, since the frame body is formed of a thin film and is composed of the cylindrical body that can expand and contract in the axial direction, and the surrounding reinforcing bars included in the cylindrical body, the compressive force in the axial direction works. Therefore, even if the concrete is greatly distorted in the axial direction, the frame body is moved or deformed in the axial direction with it, and the compressive force is received by the concrete which is strong against it. This compressive force tends to swell concrete, but the tensile force of the reinforcing bar tightens the concrete to prevent this swelling, which improves the compressive strength of the concrete and ensures the so-called confined effect. You can

Therefore, in the conventional filled steel tube concrete structure, the large yield strength generated by the conforming effect cannot be fully utilized due to the Mises yielding condition, but this invention can sufficiently guarantee it. Therefore, the cross-sectional area of the column can be reduced.

[Brief description of drawings]

1 to 8 are views showing an embodiment of the present invention. FIGS. 1 and 2 are views showing a first embodiment of the present invention. FIG. 1 is a front view of a partial cross section of a main part of the present invention, and FIG. 2 is an X- line of FIG. X-ray sectional view, FIG. 3, FIG.
FIG. 3 is a view showing a second embodiment of the present invention, FIG. 3 is a front view of a partial cross section of an essential part of the present invention, FIG. 4 is a cross sectional view taken along line YY of FIG. 5 and 6 are views showing a third embodiment of the present invention, FIG. 5 is a front view of a partial cross-section of the essential part of the present invention, and FIG. 6 is a ZZ line of FIG. FIG. 7 is a cross-sectional view of a fourth embodiment of the present invention, and FIG. 7 is a front view of a partial cross-section of the essential part of the present invention.
The drawing is a sectional view taken along the line P-P of FIG. 1 ... frame, 1a ... cylindrical, 1b ... reinforcing bar, 1c ... reinforcing bar, 3 ... concrete, 5 ... reinforcing bar, 6 ... sheath tube.

Claims (3)

[Claims] 1. A filled concrete column in which concrete is filled in a cylindrical frame body, wherein the frame body is formed of a thin film and is expandable and contractible in the axial direction thereof, and is contained in the cylinder body. A filled cylindrical concrete column comprising: a reinforcing bar extending in the circumferential direction of the cylindrical body and surrounding the concrete. 2. A filled cylindrical concrete column according to claim 1, characterized in that reinforcing bars are arranged in the concrete to be filled in the frame. 3. A filled cylindrical concrete column according to claim 1, wherein prestress is introduced into the concrete.