JPS61204456A - Filled steel pipe concrete structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a filled steel pipe concrete structure used for, for example, columns and piles of building structures.

[Conventional technology]

Conventionally, this type of filled steel pipe concrete structure is known to be made by vertically installing a steel pipe that also serves as a formwork, and pouring concrete into it.

This filling j1). Since the pipe concrete structure is simply a steel pipe filled with concrete, the steel pipe and concrete are in a bonded state and mechanically behave as one unit.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional filled steel pipe concrete structure, the steel pipe and the concrete are in an adhesive state and are constructed as one piece. Therefore, when an axial compressive force is applied to this filled steel pipe concrete structure, the steel pipe behaves as one with the concrete. Therefore, filled steel pipe concrete has its prescribed compressive strength! If f is exceeded,
The distortion of steel pipes and concrete becomes extremely difficult. As a result, the steel pipe #i becomes plastic under the Mises yield condition when local buckling occurs completely. Moreover, the concrete exceeds its compressive strength and reaches a declining range.

Therefore, in a filled concrete pipe structure, it cannot be expected that the compressive strength of the concrete will increase due to the confining effect brought about by the steel pipes (as a result, the column will have a larger cross-sectional area than necessary).

This invention was made in view of the above circumstances, and it is possible to fully expect an increase in the compressive strength brought about by the 1-filled steel pipe concrete structure, and the filled steel pipe concrete structure can make the cross-sectional area of the column smaller than that of the conventional 4-filled steel pipe concrete structure. The purpose is to provide structure.

Means for Solving Problems c] This invention has a nine-filled pipe concrete structure in which concrete is filled in a steel pipe, and the steel pipe is provided with a plurality of slits extending in the circumferential direction of the steel pipe. It is characterized by

In this invention, reinforcing bars are placed in the concrete filled in the steel pipe (and a bubble brace is introduced) to increase the strength of the member.

[Effect]

According to this invention, the above-described structure allows the steel pipe to expand and contract in the axial direction. Therefore, an axial compressive force acts on the filled steel pipe concrete structure, compressing the concrete, and when it exceeds a predetermined compressive strength, the concrete develops a large axial strain and the transverse strain begins to increase rapidly. In addition, steel pipes generate almost no axial strain and exhibit a confining effect that resists the transverse strain of concrete.

In other words, the axial force is received by the concrete cross section,
The steel pipe receives ring tension from the concrete as a reaction that gives a confining effect to the concrete.

〔Example〕

Hereinafter, this mastication will be explained with reference to FIGS. 1 to 9. FIGS. 1 and 2 are diagrams showing a practical example of @1 of the present invention, and show a filled steel pipe concrete structure. 3 and 4 are diagrams showing the second embodiment of this invention, and FIGS. 5 and 6 are diagrams showing the percentage remaining of IE3 of this invention. The figure shows a fourth embodiment of the invention.

First, Figure 1! To explain Fig. 2, the reference numeral indicates the pillar of the filled steel pipe concrete structure. This column A consists of a steel pipe 1 as a frame, a diaphragm 2 made of paper sheets attached to its inner surface, concrete 3 filled into it, and a cylindrical shape formed at its end. It is composed of a space part 4.

Here, the steel pipe 1 has linear sleeves extending in the circumferential direction.
1a61) L... is formed. This sleeve) 1
)Lsl&... is a linear notch extending in the circumferential direction of the steel pipe l, which is made into a linear slit by pulling the steel pipe 1 in the direction of arrow p to give elongation to the steel pipe 1.3
In addition, in the diaphragm 2 made of paper sheets, the concrete 3 filled at the time of construction is slit 1a a l'! L...
This is to prevent -0- from leaking. Furthermore, the cylindrical space 4 formed at the end of the steel pipe 1 is for grouting concrete or mortar into it when connecting the steel pipe 1 to another steel pipe.

To manufacture the column A, first, a steel pipe l having a plurality of linear notches 1a, 1a... extending in the circumferential direction is stretched in the direction of arrow p, and then the elongation is A diaphragm 2 is attached to the inner surface of a given steel pipe l. Concrete 3 is filled into the steel pipe l to which the diaphragm 2 is attached. At this time, a space 4 for grouting when connecting another steel pipe is formed at the end of the steel pipe 1.

In the column A manufactured in this way, since the steel pipe 1 has been stretched in advance in the axial direction C, the compressive force in the axial direction of the column AIC acts, causing large distortion in the concrete 3. However, the steel pipe 1 simply follows and contracts freely, and does not buckle.

Therefore, the steel pipe 1 can be expected to have a core finding effect on the concrete 3 without receiving almost any axial force.
As a reaction, only ring tension is received. That is, the column A receives axial force from the concrete 3, which is strong against compression, and receives ring tension from the steel pipe, which is strong against tension. As a result, the steel pipe 1 and the concrete 3 are made of custom-made materials such as the steel pipe 1 that is strong in tension and the concrete 3 that is strong in compression, respectively.The steel pipe 1 gives a confining effect to the concrete 3, and the concrete 3 gives ring tension to the steel pipe l.

Therefore, due to the synergistic effect of steel pipe 1 and concrete 3, column A is guaranteed to have a much higher compressive strength than the conventional one, and its cross-sectional area can be made several times smaller. .

Next, FIG. %II3 and FIG. 4 will be explained.

In FIGS. 3 and 4, the same elements as those shown in FIGS. 1 and 2 are designated by the same reference numerals.
4, reference numeral B indicates a column (hereinafter abbreviated as "column") of a filled steel pipe concrete structure containing reinforced concrete, and reference numeral 5 indicates a reinforcing bar. The reinforcing bars 5.5... are arranged along the circumferential direction inside the steel pipe 1 before the concrete 3 is filled into the steel pipe 1. Rebar 5.5...
・Fill concrete 3 into the reinforced steel pipe 1 to make reinforced concrete. Therefore, the column Bf'i can have a higher member strength than the column A.

Furthermore, FIGS. 5 and 6 will be explained.

In FIGS. 5 and 6, the same elements as those shown in FIGS. 3 and 4 are designated by the same reference numerals. Fifth
In FIG. 6, the symbol C is pre.

Column C (hereinafter referred to as column) has a filled steel pipe concrete structure with stressed concrete embedded therein, and the reference numeral 6 is a sheath pipe.

To manufacture column C, before concrete 3 is filled with steel pipe IK, reinforcing steel 5.5... and sheath pipe 6.6...
...Install inside the steel pipe 1. Concrete 3 is filled into a steel pipe 1 in which reinforcing bars 5.5... and sheath pipes 6.6... are installed. Next, a PCM material (not shown) is passed through a sheath f6.6 embedded in the concrete. After the concrete 3 has opened up, tension is applied to the PC steel material passed through the concrete 3, thereby introducing prestress force in the axial direction.

Therefore, when the tank remains are subjected to a force, an overturning moment is generated, and a tensile force is applied to the column C, the actual tensile stress generated is a value obtained by subtracting the prestress force.

That is, this column C can be made of a filled steel pipe concrete structure, which has a greater member strength than the columns A and B described above.

Finally, Figures 7 to 9 will be explained. 7th
In Figures 1 to 2, the same elements as those shown in Figures 1 and 2 are designated by the same reference numerals. Column C (hereinafter abbreviated as column) has a filled steel pipe concrete structure. At the joint of the pillar, concrete (or mortar) 4 is placed in the void vU4 provided at the end of the steel pipe 1.
a is grouted. Further, a separator (applying grease, oil, etc., or plastic coating 1) 0 is provided between the pipe 1 and the concrete 3 to unbond them. Figure 9 is a diagram showing the pillars being used as pillars of an actual building. In this configuration, the pillars have the same functions and effects as pillars A.

In each of the above embodiments, the filled steel pipe concrete structure column can be used as a flexible structure column because its vJt area can be reduced.

The scope of its application is conventional light (light, flexible structure) and &'
Think of a completely different type of structure, such as a super-flat building.

In addition, in order to achieve *i# formation, which generates stress only in the circumferential direction with almost no stress in the axial direction in the steel pipe, apply grease or the like to the inner surface of the wI4 pipe in cases where slits alone are not sufficient. do.

[Effect of % light] As mentioned above, this invention provides a plurality of slits extending in the circumferential direction of the wI4 pipe so that the steel pipe can freely move in the axial direction when nodal force in the axial direction is applied. Since there are nine pipes, even if the concrete is greatly distorted in the axial direction due to axial force, local buckling or yielding of the steel pipes will often occur. The axial force is applied to the concrete, which is strong in compression, and the steel pipe, which is strong in tension, is affected only by the ring tenon, which is a reaction that causes a confining effect in the concrete.

Therefore, in the conventional filled steel pipe concrete structure, it was not possible to fully expect that the compressive strength of the concrete would increase due to the Hunfind effect, but with this invention, it is possible to fully expect this.9. The cross-sectional area can be reduced.

[Brief explanation of the drawing]

fJXl decoy or Figure 6 is of this invention! ii! It is a figure showing an example of winding. 1 and 2 are diagrams showing a first practical example of the present invention. FIG. 1 is a front cross-sectional view of the main part of this invention, and FIG. Cross-sectional view, Figure 3,
Fig. 4 is a diagram showing a second practical example of this invention, p% Fig. 3 is a front sectional view of the main part of this invention, and Fig. 4 is a sectional view taken along Y-Y side of Fig. 3. , FIG. 5, and FIG. 6 are the third diagrams of this invention.
FIG. 5 is a front sectional view of the main part of the invention, and FIG. 6 is a sectional view of 2. of FIG. 5. -Z cross-sectional view, Figures 7 to 9 are diagrams showing the fourth embodiment of the present invention, Figure 7 is a front cross-sectional view of the main part of the present invention, and Figure 8 is the seventh embodiment. The cross-sectional view in the figure and FIG. 9 are explanatory diagrams for explaining the state in which the present invention is used in an actual construction. l... play'd, l a... slit,
3...Concrete, 5...Reinforcement, 6
...Sheath tube. Figure 1 Figure 2 Child thread 1) j positive ρ-> (spontaneous) ,''・~ Special 1〆l'J''l'LQ Official 1 Gakuden 1, Display of ■ 1985 Special Revised Application No. 45285 2, Name of the Invention: Filled Steel Pipe Concrete 1/Structure 3.1 Relationship with Famous Events I'1 Tezu 2-1-5g, To Chuo-ku, Tokyo (1) Each column of “Claims” and “Detailed Description of the Invention” in the detailed description. (2) Drawings. (1) The scope of claims should be attached as a separate sheet. (2) In the 4th line of page 4 of Akira, the phrase "In this invention, the steel pipe" has been changed to [In this invention, a plurality of slits are arranged in a staggered manner, and the edges of the upper and lower slits are (3) Add the following sentence in place of "formed." in line 17 of page 5. "The slit la, la, . . . are arranged in a staggered manner, and the ends of the upper and lower slits 1a, 1a, . The part where ... is not formed is continuous in the circumferential direction.'' (4) In the 9th page, line 14, [joint part] is replaced with ``
The approximately central part between the floors (the point of reversal of the moment acting on column 1 when a building receives an earthquake and an overturning moment occurs). (5) Delete "It is a pillar" from the 17th line to the 19th line of the 9th page. (6) Correct Figures 1, 3, 5, 7, and 9 as shown in the attached sheet. Claims (1) A filled steel pipe concrete drawing in which a steel pipe is filled with concrete, characterized in that the steel pipe is provided with a plurality of slits extending in the circumferential direction of the steel pipe. structure. Ll! 1) The filled steel pipe concrete structure according to claim 1, characterized in that reinforcing bars are arranged in the concrete filled in the pipe. The filled steel pipe concrete structure according to claim 1, wherein a prestressing force is introduced into the concrete. ff summer! The filled steel pipe concrete 1 structure according to claim 1, wherein a plurality of circumferentially extending slits are provided only in the stop 1. (6) The full Iattllll pipe concrete structure according to claims 1 or 2, characterized in that a separator is formed on the inner surface of the wI pipe to prevent adhesion of concrete 1. .

Claims (5)

[Claims] (1) A filled steel pipe concrete structure in which a steel pipe is filled with concrete, wherein the steel pipe is provided with a plurality of slits extending in the circumferential direction of the steel pipe. (2) The filled steel pipe concrete structure according to claim 1, characterized in that reinforcing bars are arranged in the concrete filled in the steel pipe. (3) The filled steel pipe concrete structure according to claim 1, characterized in that a prestress force is introduced into the concrete. (4) The filled steel pipe concrete structure according to claim 1, characterized in that a plurality of circumferentially extending slits are provided only at joints of the steel pipes. (5) A filled steel pipe concrete structure according to claims 1 to 4, characterized in that a separator is formed on the inner surface of the steel pipe to prevent concrete from adhering.