JPS5831931Y2 - steel concrete column - Google Patents

Description

[Detailed description of the invention] This invention relates to a steel-framed concrete column using two channel steels.

The applicant first developed two channel-shaped steel structures as a structure that has a mechanism in which the steel frame and concrete work together to resist external forces, and the steel frame can be easily processed and assembled using a small amount of steel. are arranged with their flange end faces facing each other, the flanges are connected by a tie plate at an appropriate interval, and a diaphragm is fixed to the inside of the web in the connection plane, and then concrete is poured. We developed a pillar and applied for a patent.

In steel-framed concrete columns like the ones mentioned above, the poured concrete acts like a truss material and has extremely good cross-sectional performance, but in the event of a major earthquake, cracks can occur in the surrounding concrete and the concrete in the fireproof coating. There was a problem that this caused the product to peel off.

The above-mentioned problems are not limited to steel-framed concrete columns using channel steel as described above, but are problems that occur in all general steel-framed concrete or steel-framed reinforced concrete structures.
As a solution to this problem, a method as shown in schematic cross-sectional views in FIGS. 1 to 5 has conventionally been used.

That is, in Fig. 1, main column reinforcements 2 are provided so as to surround a column steel frame 1 made of H-beam steel, hoop reinforcements 3 are wrapped around the main column reinforcements 2, and then Conc'J-N1 is cast. In Fig. 2, main column reinforcements 2 are provided so as to surround a column steel frame 1 made of two channel steels arranged facing each other, and U-shaped hoop reinforcements 3° 3' are attached to the main column reinforcements 2. It is wound so that the parts overlap.

Further, in Fig. 3, short reinforcing bars are welded to the flange of the column steel frame 1 made of H-shaped steel as reinforcing bars 4, and in Fig. 4, stud dowels 5 are planted around the outer periphery of the column steel frame 1 made of square columns. The figure shows a column steel frame 1 made of H-section steel that is surrounded by mesh-like small-diameter reinforcing bars 6.

As mentioned above, the conventional method is to wrap stirrups such as hoop reinforcements 3 or mesh-like small diameter reinforcing bars 6 around the entire circumference of the column steel frame 1, or to wrap reinforcing bars 4 or stud dowels around the column steel frame 1. Since the structure requires welding, etc., it takes time and effort to process and install, and there are problems such as requiring a long period of time for construction.

From the above-mentioned viewpoints, this idea provides a steel-framed concrete column that can easily and reliably prevent the outer concrete from cracking and falling off in the event of a major earthquake, etc. Channel steels are arranged with their flange end faces facing each other, the flanges are connected at an appropriate interval by tie plates, and concrete is poured in the area surrounded by and around the channel steels. In the steel-framed concrete column formed by the above-mentioned method, on the outer periphery of each of the channel steels, a mesh-like reinforcing bar made of thin reinforcing bars is formed, and a bent part is formed from near the tip of the flange of the channel steel toward the center. It is characterized by the fact that it is arranged at least.

Next, the steel-framed concrete column of this invention will be explained with reference to an example and drawings.

FIG. 6 shows a schematic sectional view of the fractured area of concrete, and FIGS. 7 and 8 show schematic sectional views of the reinforcing structure of this invention.

The inventors of the present invention have conducted various tests on the fracture properties of a steel-framed concrete column in which two channel steels are arranged with their flange end faces facing each other to form a column steel frame.
As shown in FIG. 6, the flange 7a of the channel steel 7.7'
, 7a', 7b, 7b' and web 7c, 7
The adhesion failure and peeling area a of the concrete that occurs on the outer surface of c′ and the crushing and shear failure area that occurs from the vicinity of the end faces of flanges 7a and 7b toward the center of It was found that there was a relatively sound region C on the inner surface of the flange 7 a + 7 b N wip 7c.

Based on the above test results, this design has a structure that provides appropriate reinforcement for areas where crushing or peeling occurs.
, 7b and 7a', 7b' are arranged opposite to each other.
This is a tie plate that connects b and 7b' at an appropriate interval.

In this invention, as shown in FIG. 9A, reinforcing bars 10 made by welding vertical bars 9a and horizontal bars 9b made of thin reinforcing bars in a mesh pattern are attached to each of the channel steels 7 and 7'. Flanges 7a, 7 of the channel steel 7゜7' are attached to the outer periphery.
A bent portion 10a surrounds the tips of b, 7a' and 7b' and extends toward the center.

10b is formed, and concrete 1
1 was poured.

Note that since a lattice-like tie plate (not shown) is attached to the inside of the channel steel 17', the vertical reinforcements 9a at the bent portions 10a, 10b of the reinforcing reinforcement 10 are completely or partially removed. shall be removed.

According to the above-described structure, the column shaft portion, etc., channel steel 7, 7
'7 lunges 7a, 7a', 7b, 7b
It is possible to completely prevent concrete adhesion failure, peeling failure, etc. that occur on the outer peripheral surfaces of ' and webs 7c and 7c'.

FIG. 8 shows another embodiment of this invention, in which the opposing channel steel 7,
The width between 7' is wide and the shear strength is insufficient, so the flange? a,? If shear failure or crushing occurs from the vicinity of the end faces of a', 7b, and 7b' toward the center, surround the outer periphery of one channel steel 7 and break the flange 7a.
, 7b from the outside, the flange 7a of the other channel steel 7',
7b' Reinforcement bar 1 that extends at the edge near the end and has bent portions 10a and 10b formed from near the end toward the center.
0 and the other channel steel 7', surrounding its flange?
Flange 7a of one channel steel 7 from the outside of a', 7b'
, 7b, a bent portion 10a extending near the end 1 and extending from near the end toward the center.

Reinforcing bars 10' having reinforcement bars 10b' are provided, and then concrete 11 is poured.

According to the above-mentioned structure, there is also the effect of reinforcing the shear strength in the concrete part, and it is possible to prevent concrete adhesion failure and peeling failure that occur on the outer peripheral surface of the channel steel.
Shear failure and crushing that occur from the vicinity of the end face of the flange toward the center can be completely prevented.

As shown in FIG. 9B, the reinforcing bars 10°10' have bent portions 10a, 10b and 10a', 1
The vertical stripes 9a, 9a' at 0b' are completely or partially removed, similar to the embodiment shown in FIG. 7 above.

As explained above, according to the steel-framed concrete column of this invention, the concrete can be easily removed from the channel steel, which is the main reinforcement of the column, in the event of an earthquake etc. without using complicated means such as welding. Industrially useful effects are brought about, such as being able to prevent damage and destruction, requiring less effort in processing and construction, and allowing construction to be completed in a short period of time.

[Brief explanation of the drawing]

Figures 1 to 5 are schematic cross-sectional views showing conventional steel concrete IJ-4 columns, Figure 6 is a schematic cross-sectional view showing the fractured area of concrete, and Figures 7 and 8 are steel concrete concrete of this invention. A schematic sectional view showing a column, and FIG. 9 is a perspective view showing an example of reinforcing bars used in the steel-framed concrete column of this invention. In the drawing, 1... - Column steel frame, 2... Column main reinforcement, 3...
...Hoop muscle, 4...Reinforcement muscle, 5...
...Stud dowel, 6...Mesh reinforcing bar, 7,
7'... Channel steel, 8, 8'... Tie plate, 9a... Vertical bar, 9b... Horizontal bar, 10... - Reinforcement bars, 11... bent concrete.

Claims (1)

[Claims for Utility Model Registration] Two channel steels are arranged with their flange end faces facing each other, the flanges are connected by a tie plate at an appropriate interval, and the channel steel is surrounded by one In a steel-framed concrete column formed by pouring concrete in the area and surrounding area, mesh reinforcing bars made of thin reinforcing bars are installed around the outer periphery of each of the channel steels at the tips of the flanges of the channel steels. A steel-framed concrete column characterized in that it is arranged with a bent part formed from the vicinity of the part toward the center.