JPH0768741B2 - Steel concrete beam - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel-framed concrete beam as a structure in the fields of construction, civil engineering and the like.

[0002]

2. Description of the Related Art In a building such as a high-rise house, it is desired that the beam has a high rigidity so as to be adaptable to a large span so as to improve habitability.

As a beam having such a high rigidity, as shown in FIG. 13, the beam 1 is arranged with the steel frame 2 at the center, the reinforcing bar 3 is arranged in the vicinity thereof in parallel with the steel frame 2, and the hoop bar is arranged around the beam. It is generally composed of a steel-framed reinforced concrete beam surrounded by 4. As another example, as shown in FIG. 14, a channel material 5 of U-shaped steel plate corresponding to the outer circumference of the beam is used, the reinforcing bars 3 are arranged in the length direction near the upper opening, and concrete is placed inside the channel material 5. The beam 1 may be formed by casting. 13 and 14, 6 is a slab, and 7 is a deck plate for constructing the slab 6.

Also, although it is a type found in Western Europe, a beam steel frame 8 is used as shown in FIG.
Reinforcing bar 9 is reinforced on the web part of
a, 10b are cast on site and the steel frame reinforced concrete (S
There is also a beam 1 of RC). In the case of FIG. 15, when the beam steel frame 8 is on the ground, the web is turned upside down on either side and concrete 10a is placed therein. When this is hardened, the beam steel frame 8 is turned over and the other webs are turned upside down. Then, concrete 10b is placed here.

[0005]

The one shown in FIG. 13 is far from labor saving because the arrangement of the formwork for placing the beam concrete and the work of arranging the reinforcing bar 3 and the hoop bar 4 are troublesome. is there. Since the steel plate forming the channel material 5 is thin and the reinforcing bar 3 is the main reinforcing bar in the structure shown in FIG. 14, it is difficult to bond it to a steel frame (S) -based column (including a steel pipe concrete column).

The structure shown in FIG. 15 uses the beam steel frame 8 and therefore is excellent in the method of joining to a steel frame column, and transports heavy objects from the factory to the site like a reinforced concrete type precast beam manufactured by the factory. There is no need. However, in order to cast the concrete 10a, 10b, the work of reversing the beam steel frame 8 must be performed as described above, and the reinforcing bar 9
The work of arranging is also troublesome.

The object of the present invention is to eliminate the disadvantages of the above-mentioned conventional examples, facilitate the joining to steel-framed columns, do not require reversal work to fill the web with concrete, and can also omit the bar arrangement. Therefore, it is to provide a steel-framed concrete beam with high rigidity that can further reduce the labor.

[0008]

In order to achieve the above-mentioned object, the present invention is designed such that the flanges are slightly protruded to the outside to form recesses between the upper and lower flanges on the outer side of the web, and the inner side of the web is provided between the upper and lower flanges. Forming a large void, arranging two channel steels filled with concrete here, and tightening and fixing each other with high-strength long bolts whose ends fit into the void formed in the concave portion on the outside of the web. , And, using a channel steel having an opening face of a void portion formed inside the web on the inside and protruding outwardly at the upper and lower ends thereof with outwardly facing flanges for joining, The gist of the present invention is to make two grooved steels filled with concrete inside and to fasten and fix the joint flanges to each other with high-strength bolts.

[0009]

According to the present invention as set forth in claim 1, the inside of the web is filled with concrete, and the concrete is constrained by fastening channel steels together with bolts.
Moreover, since the channel steel acts as if it were a rebar, the so-called confined effect is obtained, and no rebar is required.

Further, the channel steel is easy to join to a steel frame column as a steel frame, and if the channel steel is filled with concrete before two pieces are aligned, the reversing work becomes unnecessary.

Moreover, since the concrete filling the inside of the web can be restrained by fastening the channel steels together with the high-strength bolts, no troublesome work is required and anyone can easily carry out the work. You can do it, and it does not take much time.

Further, although the ends of the high-strength long bolts for fastening the outer sides of the facing channel steels to each other are exposed to the outside,
Both ends of this high-strength long bolt fit into the recesses formed on the outside of the web on both sides, so if the decorative plates are laid between the upper and lower flanges on the outside of this channel steel to conceal them, there will be no protrusion. It will look good.

According to the second aspect of the present invention, the high-strength bolts for fixing the two aligned channel steels to each other need not be long, but need only be short, so that they are easy to handle. In addition, since the length is short, it can be ordered at low cost.

Further, since the joining flange of the channel steel projects in a certain direction, for example, when it comes out on the ceiling surface and becomes an obstacle, the whole is made sideways and the joining flange, high-strength bolts, etc. are made of a steel concrete beam. Can be positioned on the side of the sheet, and if the direction of the whole is changed in this way, it is possible to respond appropriately even if there is a design change without disturbing.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a vertical sectional side view showing a first embodiment of a steel-framed concrete beam of the present invention, in which 11 is a channel steel of substantially I shape,
A large gap is formed inside the web 11b by projecting largely inside the flange 11a, and a relatively shallow recess is formed outside the web 11b by projecting slightly outside.

These two channel steels 11 are put together to form a box-like shape. Concretely, the voids inside the webs 11b of the channel steels 11 are filled with concrete 12, and the channel steels 11 are connected to each other by the concrete 12. It was fixed with a high-strength long bolt 13 penetrating through.

In the figure, 14 is a washer, and 15 is a nut for tightening the bolt 13. The ends of the high-strength long bolt 13, the washer 14, and the bolt 13 are exposed to the outside, but the web 11b
It is designed to fit in the recess between the upper and lower flanges 11a on the outer side of.

A decorative plate 29 is erected between the upper and lower flanges 11a on the outside, and the decorative plate 29 is attached to the outer surface of the channel steel 11 to conceal the end of the high-strength long bolt 13 and the washer 14 so that the protrusion is formed. It disappears, and it looks good.

As a method of filling the concrete 12, the respective grooved steels 11 are concreted before the two grooved steels 11 are put together.
There are two methods available, one is to fill 12 with the concrete, and the other is to align the channel steels 11 first and fix with high strength long bolts 13 and then fill the concrete 12 inside. is there.

The steel-framed concrete beam 16 thus obtained
The stud bolt 17 is projected on the upper surface of the channel steel 11, and in the example shown in the figure, the end of the deck plate 7 is mounted on the channel steel 11 and the floor reinforcement 18 is reinforced to make the floor concrete. Place 19

2 and 4 show a second embodiment of the present invention, in which the channel steel 20 has a channel-like shape with a U-shaped cross section.
With the opening surface of the void portion formed inside the web 20a as the inside, flanges 20b for joining that are continuous to the outside along the longitudinal direction are provided at the upper and lower ends thereof. Concrete 12 is filled inside the web 20a of each channel steel 20, and the two joint flanges 20b are fastened and fixed using high-strength bolts 21, washers 14, and nuts 15.

FIG. 3 shows a modification of the second embodiment. In the example of FIG. 2, the high-strength bolt 21 on the lower flange side may come out of the ceiling surface and become an obstacle. The joining flange 20b, the high-strength bolt 21, and the like are located on the side of the steel-framed concrete beam 16.

Further, when the two pieces are put together, if the surface of the concrete 12 is thinly coated with mortar 30 or the like, when tightened with the high-strength bolts 21 or the like, friction between the concretes can be expected, and the load of the bolts can be expected. Can be reduced. The same applies to the case of the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. 2. If the application of mortar is troublesome, concrete 12
It should be installed so that the surface of is raised a little.

As a method of filling the concrete 12, as shown in FIGS. 6 to 8, each grooved steel 20 is filled with the concrete 12 before the two grooved steels 20 are aligned with each other. The method of joining those can be adopted.

Steel-framed concrete beam 16 thus obtained
The same as in the first embodiment is that the end of the deck plate 7 is mounted on the channel steel 11, the floor rebars 18 are laid and the floor concrete 19 is placed to assemble the floor concrete 19. In particular, the joint flange 20b serves as a cotter as it projects above the steel-concrete beam 16.

As a third embodiment, an intermittent connecting flange 20c as shown in FIG. 5 may be used instead of the continuous connecting flange 20b in the longitudinal direction of the second embodiment. By doing so, the reinforcing bar 22 as the bottom end bar of the floor can be arranged at the intermittent portion between the joining flanges 20c.

Further, showing an example of the connection between the steel-framed concrete beam 16 and the steel-framed column of the present invention as described above, as shown in FIGS. 9 and 10, the steel-framed column 23 and the steel-framed concrete beam 16 are respectively provided with brackets. It is possible to adopt a normal method of joining steel columns and steel beams in which 24 are provided and the brackets 24 are joined together by the gusset plate 25 and the splice plate 26. in this case,
Although there is no concrete in the bracket 24 portion, there is no problem because the rigidity is considerably increased by the splice plate 26 and the like.

As another example, as shown in FIGS. 11 and 12, two joint plates 27 are projected from a steel column 23, and the two joint plates 27 sandwich both sides of the steel concrete beam 16. In this way, high strength long bolts 28 can also be used for through fixing.

[0029]

As described above, the steel-concrete beam of the present invention can be easily joined to a steel-framed column, and inversion work is not required to fill the web with concrete.
Moreover, since the reinforcing bar can be omitted, it is a highly rigid beam that can further save labor.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a steel frame concrete beam of the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the steel-framed concrete beam of the present invention.

FIG. 3 is a vertical sectional view showing a modification of the second embodiment of the steel frame concrete beam of the present invention.

FIG. 4 is a side view showing a second embodiment of the steel frame concrete beam of the present invention.

FIG. 5 is a side view showing a third embodiment of the steel frame concrete beam of the present invention.

FIG. 6 is a perspective view of a first step showing the filling of concrete.

FIG. 7 is a perspective view of a second step showing the filling of concrete.

FIG. 8 is a perspective view of a third step showing the filling of concrete.

FIG. 9 is a side view showing an example of a first joint with a steel column.

FIG. 10 is a plan view showing a first example of connection with a steel column.

FIG. 11 is a side view showing a second example of a joint with a steel column.

FIG. 12 is a plan view showing a second example of a connection with a steel column.

FIG. 13 is a vertical sectional view showing a conventional example.

FIG. 14 is a vertical cross-sectional view showing another conventional example.

FIG. 15 is a vertical cross-sectional view showing another conventional example.

[Explanation of symbols]

1 ... Beam 2 ... Steel frame 3 ... Beam reinforcing bar 4 ... Hoop bar 5 ... Channel material 6 ... Slab 7 ... Deck plate 8 ... Beam steel frame 9 ... Reinforcing bar 10a, 10a ... Concrete 11 ... Channel steel 11a ... Flange 11b ... Web 12 ... Concrete 13… High-strength long bolt 14… Washer 15… Nut 16… Steel concrete beam 17… Stud bolt 18… Floor rebar 19… Floor concrete 20… Channel steel 20a… Web 20b, 20c… Joint flange 21… High strength bolt 22 ... Reinforcing bar 23 ... Steel column 24 ... Bracket 25 ... Gusset plate 26 ... Splice plate 27 ... Joining plate 28 ... High strength long bolt 29 ... Decorative plate 30 ... Mortar etc.

Claims (2)

[Claims] 1. A flange is projected to the outside to some extent to form a recess between the upper and lower flanges on the outer side of the web, and a large space is formed between the upper and lower flanges on the inner side of the web, and is filled with concrete. A steel-concrete beam, comprising two channel steels, which are fastened to each other by high-strength long bolts whose ends fit in a void formed in a recess on the outside of the web. 2. A grooved steel having an opening face of a void portion formed inside the web inside and an outward joining flange projecting continuously along the longitudinal direction at the upper and lower ends thereof is used. A steel-framed concrete beam, characterized in that two grooved steels for filling concrete are aligned inside the web, and the joining flanges are fastened and fixed to each other with high-strength bolts.