JP2018172870A - Reinforcing bar cage and method of building reinforcing bar cage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a reinforcing bar cage having a structure with enhanced adhesion strength simply and a method of building the reinforcing bar cage.SOLUTION: A reinforcing bar cage 100 has a plurality of flexible reinforcing bars 10 disposed at appropriate intervals in the circumferential direction and one or more hoops 20 wound around the plurality of flexible reinforcing bars 10. At least a pair of the plurality of flexible reinforcing bars 10 are connected to each other so as to have a downwardly convex U shape at the lower end portion of the reinforcing bar cage 100 so as to have a U-shaped fixing portion 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a reinforcing bar rod using a flexible reinforcing bar and a method for building a reinforcing bar rod using a flexible reinforcing bar.

  Conventionally, in order to achieve good fixation of the flexible reinforcing bars that are the main reinforcing bars of cast-in-place piles, condominium processing is performed by attaching a crimping grip and anchor plate to the tip of the flexible reinforcing bars, or the tip of the flexible reinforcing bars is A technique is known in which a crushing part formed by crushing is filled with a fluid hardener to form a spherical part to increase its adhesion strength (see, for example, Patent Document 1).

JP 11-36289 A

  However, the work of forming the fixing portion such as the ball lump portion on the flexible reinforcing bar must be performed manually one by one, which is cumbersome. Has a problem that the construction period and construction cost increase and the construction cost may increase due to the work time required.

  An object of the present invention is to provide a reinforcing bar rod having a structure in which adhesion strength is easily increased, and a method for installing the reinforcing rod rod.

In order to achieve the above object, one invention according to the present application is
A rebar rod having a plurality of flexible rebars arranged at appropriate intervals in the circumferential direction and one or a plurality of strips wound around the plurality of flexible rebars,
Among the plurality of flexible reinforcing bars, at least one pair has a structure connected so as to exhibit a downward U-shape at the lower end portion of the reinforcing bar rod.

The reinforcing bar rod having such a configuration includes a fixing part having a structure in which a flexible reinforcing bar is connected to the lower end of the reinforcing bar so as to form a convex U shape.
If it is a fixing part that is connected so that the flexible rebar has a U-shape, for example, only one flexible rebar is folded back at the center, or the lower ends of two flexible rebars are connected to each other with a connector. It can be formed simply by doing.
In addition, if the fixing portion has a convex U-shape, a large pulling resistance can be exerted by placing concrete inside the U-shape. And the adhesion strength of the reinforcing bar can be increased.

Also, preferably
The flexible reinforcing bar presenting a U shape at the lower end of the reinforcing bar rod is formed by bending one flexible reinforcing bar.
The fixing part in which the flexible reinforcing bars are connected in a U shape can be formed by connecting with a connection tool, etc., but by forming the fixing part by a method of folding one flexible reinforcing bar at the center part, The operation of forming the fixing portion on the flexible reinforcing bar (reinforcing bar) can be further simplified.

Also, preferably
The reinforcing bar rod is configured to be deformable into a structure in which the plurality of flexible reinforcing bars along the longitudinal direction thereof are bent into an arc shape and deformed in a spiral shape, and the length thereof is shortened.
Thus, if it can deform | transform into the structure which reduced the reinforcing bar rod, it will become easy to carry in to a construction site.

Also, other inventions related to this application are:
Reinforcing bar erection method of building a reinforcing bar rod having a plurality of flexible reinforcing bars arranged at appropriate intervals in the circumferential direction and a band rod wrapped around the plurality of flexible reinforcing bars in a pile hole,
A step of installing at least one set of drum devices each wound around both ends of the flexible rebar in an arrangement sandwiching the pile holes;
Feeding each of the flexible rebars from the set of drum devices and feeding a portion of the flexible rebar bent downward in a convex U-shape into the pile hole between the set of drum devices;
Winding a band around a plurality of flexible rebars fed into the pile hole;
It was made to have.

With the reinforcing bar erection method having such a configuration, it is possible to easily form a fixing portion having a structure in which the flexible reinforcing bar is bent at the lower end of the reinforcing bar so as to form a U-shape projecting downward.
And if it is a fixing | fixed part which exhibits a convex U character shape below, since a big pulling-out resistance force will be exhibited, the vertical supporting force of the pulling-out direction of a reinforcing bar will be improved, and the adhesion strength of a reinforcing bar will be able to be raised.

Also, preferably
The set of drum devices is wound in advance with flexible reinforcing bars having a length corresponding to at least the depth of the pile hole.
By carrying out like this, the reinforcing bar which provided the fixing | fixed part by which a flexible reinforcing bar is connected so that a convex U-shape may be exhibited below can be built in a pile hole suitably.

Also, other inventions related to this application are:
Reinforcing bar erection method of building a reinforcing bar rod having a plurality of flexible reinforcing bars arranged at appropriate intervals in the circumferential direction and a band rod wrapped around the plurality of flexible reinforcing bars in a pile hole,
The flexible rebar is bent in a U-shape projecting downward at the lower end of the rebar bar, and the flexible bar is removed by spiraling the flexible bar excluding the U-shaped part; and
Extending the reinforcing bar rod from the top of the pile hole into the pile hole while returning the spiral portion of the flexible reinforcing bar in the reduced size of the reinforcing bar to a straight line; and
It was made to have.
If it is the construction method of the reinforcing bar with such a structure, the reinforcing bar having a fixing part with a structure in which the flexible reinforcing bar is bent so as to form a convex U shape at the lower end thereof is suitably installed in the pile hole. be able to.

  According to the present invention, it is possible to obtain a reinforcing bar rod having a structure in which adhesion strength is easily increased.

It is the schematic of the reinforcing bar rod of Embodiment 1. It is explanatory drawing (a) (b) (c) (d) (e) (f) which shows the pattern which the flexible rebar of a rebar rod makes a pair. It is explanatory drawing (a) (b) (c) which shows the construction method of the reinforcing bar cage of Embodiment 1. FIG. It is the schematic of the reinforcement rod of Embodiment 2, and is the state (a) which extended the reinforcement rod, the state (b) in the middle of expansion or contraction of the reinforcement rod, and the state (c) which the reinforcement rod was contracted Show. It is explanatory drawing (a) (b) (c) (d) which shows the construction method of the reinforcing bar cage of Embodiment 2. FIG.

  Hereinafter, with reference to drawings, an embodiment of a reinforcing bar rod and a reinforcing bar rod mounting method according to the present invention will be described in detail. However, the embodiments described below are given various technically preferable limitations for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

(Embodiment 1)
As shown in FIG. 1 and FIG. 2A, the reinforcing bar rod 100 according to the first embodiment is wound around a plurality of flexible reinforcing bars 10 and a plurality of flexible reinforcing bars 10 arranged at appropriate intervals in the circumferential direction. And a spiral band 20.

The flexible rebar 10 is a rebar having flexibility, which is also referred to as a strand rebar, for example, a rebar made of a material that does not cause a problem in strength even when bent to the same degree of curvature as the band rebar 20. For this flexible rebar 10, for example, a material obtained by twisting materials such as carbon fiber, glass fiber, and aramid fiber in addition to a stranded wire and a wire rope can be used.
As shown in FIG. 1, the band 20 is obtained by winding a reinforcing bar around a plurality of flexible reinforcing bars 10 in a spiral shape.

In particular, the plurality of flexible reinforcing bars 10 in the reinforcing bar rod 100 of the present embodiment has a structure that is connected so as to exhibit a downward U-shape at the lower end portion of the reinforcing bar rod 100.
In other words, the plurality of flexible reinforcing bars 10 along the longitudinal direction of the reinforcing bar rod 100 are connected to form a downward U-shape at the lower end portion of the reinforcing bar rod 100 to form a pair.
For example, when eight flexible reinforcing bars 10 are arranged along the longitudinal direction of the reinforcing bar 100, as shown in FIG. 2A, "a" and "e", "b" and "f" , “C” and “g”, and “d” and “h”, the flexible reinforcing bars 10 are connected so as to form a pair of U-shapes. A character-shaped fixing portion 11 is formed.
The U-shaped fixing unit 11 having a U-shape that protrudes downward can exert a large pulling resistance when concrete is placed inside the U-shaped part. The vertical supporting force in the pulling direction of the rod 100 can be increased, and the adhesion strength of the reinforcing rod 100 can be increased.

Note that the pattern in which the flexible reinforcing bars 10 form a pair is not limited to this. For example, as shown in FIG. 2B, “a” and “f”, “b” and “e”, “c” and “g” ”,“ D ”and“ h ”, the flexible reinforcing bars 10 may be paired.
Further, as shown in FIG. 2C, the flexible reinforcing bars 10 at positions “a” and “f”, “b” and “e”, “c” and “h”, “d” and “g” are provided. May be paired.
Further, as shown in FIG. 2D, the flexible reinforcing bars 10 at positions “a” and “f”, “b” and “e”, “c” and “d”, “g” and “h” are provided. May be paired.
Further, as shown in FIG. 2E, the flexible reinforcing bars 10 at positions “a” and “g”, “b” and “d”, “c” and “e”, “f” and “h” are provided. May be paired.
Further, as shown in FIG. 2 (f), the flexible reinforcing bars 10 at the positions "a" and "b", "c" and "d", "e" and "f", and "g" and "h" are provided. May be paired.

Even if the U-shaped fixing portion 11 formed of the flexible reinforcing bars 10 paired in such an arrangement has a structure in which one flexible reinforcing bar 10 is bent, the two flexible reinforcing bars 10 are arranged. You may have the structure where the lower ends of were connected using connection tools, such as a coupler.
For example, when the U-shaped fixing portion 11 has a structure in which one flexible reinforcing bar 10 is bent, a reinforcing bar 100 including four flexible reinforcing bars 10 is arranged along the longitudinal direction of the reinforcing bar 100. Apparently, eight flexible reinforcing bars 10 are arranged.

  Next, a procedure for building the reinforcing bar 100 into the pile hole H will be described.

  At the construction site of the cast-in-place pile, as shown in FIG. 3A, the place where the cast-in-place pile is created is excavated to form the pile hole H, and the band winding device is directly above the pile hole H. 4 is provided, and a built-in stand 7 provided with a lowering device 6 such as a hanging wire drum is provided on the upper part thereof.

Moreover, as shown to Fig.3 (a), the drum apparatus 8 which wound up the both ends of the one flexible rebar 10 in the arrangement | positioning which pinches the pile hole H, respectively is installed in a pair.
Each of the pair of drum devices 8 is wound beforehand with flexible reinforcing bars 10 each having a length corresponding to at least the depth of the pile hole H (that is, the design length of the cast-in-place pile).
In addition, when assembling and building the reinforcing bar rod 100 in which eight flexible reinforcing bars 10 are apparently arranged along the longitudinal direction, four sets (four pairs) of drum devices 8 are installed.

And as shown to Fig.3 (a), it is U between the drum apparatus 8 which makes a pair, and bends the flexible rebar 10 in the convex U shape so that it may be located just above the pile hole H. A character-shaped fixing unit 11 is formed.
An annular lower frame 13 is attached to the plurality of flexible reinforcing bars 10 in the vicinity of the U-shaped fixing unit 11. The lower frame 13 is a known member used for arranging a plurality of flexible rebars 10 at predetermined intervals in the circumferential direction and securing the shape of the reinforcing bar rod.
The lower frame 13 is connected to the wire of the lowering device 6.

Next, as shown in FIG. 3 (b), the flexible reinforcing bars 10 are respectively fed out from the paired drum devices 8, and the flexible reinforcing bars 10 are bent downwardly in a U-shape between the paired drum devices 8. The (U-shaped fixing part 11) is fed into the pile hole H.
Further, while feeding the flexible reinforcing bar 10 into the pile hole H, the band 20 is wound around the plurality of flexible reinforcing bars 10 fed into the pile hole H by the band winding device 4 in a spiral shape.
At this time, the lower frame 13 is lowered toward the bottom of the pile hole H by the lowering device 6. In the process of feeding the flexible reinforcing bar 10 into the pile hole H, a known intermediate frame for arranging a plurality of flexible reinforcing bars 10 at predetermined intervals in the circumferential direction is appropriately attached, and the inner space of the reinforcing bar is secured by the annular intermediate frame. You may make it do.

Then, as shown in FIG. 3C, if the U-shaped fixing portion 11 at the lower end of the reinforcing bar 100 reaches the vicinity of the bottom surface of the pile hole H to form the reinforcing bar 100 having the designed length, The construction of the casket 100 is substantially finished.
When the lower end part (U-shaped fixing part 11) of the reinforcing bar 100 reaches the vicinity of the bottom surface of the pile hole H, the band 20 is wound up to a position corresponding to the upper opening of the pile hole H. Moreover, when the lower end part (U-shaped fixing part 11) of the reinforcing bar 100 reaches the vicinity of the bottom surface of the pile hole H, the annular upper frame 14 is attached to the flexible reinforcing bar 10 at a position corresponding to the upper opening of the pile hole H. Install it. The location where the upper frame 14 is attached is the upper end of the reinforcing bar 100.
And by replacing the upper frame 14 portion of the upper end portion of the reinforcing bar 100 with a Kanzashi steel material (not shown) installed in the upper opening of the pile hole H in a conventionally known procedure, Finish building the rebar fence 100.
And a cast-in-place pile can be constructed by placing concrete in the pile hole H in which the reinforcing bar 100 is built.

According to the building method of the reinforcing bar by such a building procedure, the reinforcing bar is provided with the U-shaped fixing part 11 in which the flexible reinforcing bar 10 is connected in a convex U-shape at the lower end. 100 can be built into the pile hole H.
And if the U-shaped fixing | fixed part 11 is provided in the lower end part of the reinforcing bar 100, the adhesion strength of the reinforcing bar 100 can be increased.
In particular, while feeding the portion where the flexible rebar 10 is bent into a U shape between the pair of drum devices 8 into the pile hole H, the strap 20 is wound around the plurality of flexible rebars 10 to form a U shape. Since the reinforcing bar 100 provided with the fixing portion 11 can be easily built in the pile hole H, the reinforcing bar 100 having a structure with improved adhesion strength can be easily formed.

  In the first embodiment described above, a pair of drum devices 8 each having both ends of one flexible rebar 10 wound around the pile hole H are installed, and the flexible rebar 10 is placed between the drum devices 8. Although the U-shaped fixing part 11 formed by bending in a U-shape is formed, a pair of drum devices 8 each wound up with the flexible reinforcing bars 10 are installed in the arrangement sandwiching the pile holes H, and are fed out from the respective drum devices 8. Alternatively, the ends of the flexible reinforcing bars 10 may be connected directly above the pile hole H to form the U-shaped fixing portion 11.

(Embodiment 2)
Next, a second embodiment of the reinforcing bar rod and the reinforcing bar mounting method according to the present invention will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and only different parts will be described.

  As shown in FIG. 4A and FIG. 2A, the reinforcing bar rod 100 according to the second embodiment includes a plurality of flexible reinforcing bars 10 and a plurality of flexible reinforcing bars 10 arranged at appropriate intervals in the circumferential direction. It is provided with a plurality of wrapped strips 20.

For example, the reinforcing bar 20 is formed by bending a reinforcing bar into an annular shape and joining both ends by welding. The band 20 is preferably a welded closed band.
Moreover, in order to ensure the assembly precision of the reinforcing bar 100, the band 20 is preferably a perfect circle.

The flexible rebar 10 is a rebar having flexibility, which is also referred to as a strand rebar, for example, a rebar made of a material that does not cause a problem in strength even when bent to the same degree of curvature as the band rebar 20.
For this flexible rebar 10, for example, a material obtained by twisting materials such as carbon fiber, glass fiber, and aramid fiber in addition to a stranded wire and a wire rope can be used.

The flexible reinforcing bar 10 and the band 20 are connected by a rotation coupling jig (not shown) disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-89960.
The rotary coupling jig is a member that is attached to the intersection of the flexible reinforcing bar 10 and the reinforcing bar 20 and is coupled so that the intersection angle of the flexible reinforcing bar 10 and the reinforcing bar 20 can be adjusted.
Then, when the flexible reinforcing bar 10 is bent in an arc shape so as to twist the reinforcing bar 100 shown in FIG. 4A, the crossing angle between the flexible reinforcing bar 10 and the band 20 becomes small, and FIG. 4B and FIG. As shown in the figure, the flexible reinforcing bar 10 is spiraled and the bar spacing of the band 20 is gradually reduced, so that the length of the reinforcing bar 100 can be shortened.

Below, the procedure in which the reinforcing bar 100 of Embodiment 2 is built in the pile hole H is demonstrated.
The reinforcing bar 100 of the first embodiment described above was of the type that is built into the pile hole H while being assembled at the construction site of the cast-in-place pile, but the reinforcing bar 100 of the second embodiment is a reinforcing bar manufactured at a factory. This is a type in which the anchor 100 is carried into the cast-in-place pile construction site and built into the pile hole H.

The reinforcing bar 100 is manufactured in a factory corresponding to the length of the cast-in-place pile.
The reinforcing bar 100 manufactured at the factory is bundled with a predetermined band member in a state in which the length thereof is shortened and reduced, and is carried into the construction site of the cast-in-place pile.
At the construction site of cast-in-place piles, as shown in FIG. 5 (a), the place where the cast-in-place pile is created is excavated to form a pile hole H, and the erection platform 1 is directly above the pile hole H. is set up.
Then, using the construction machine 3 such as a crawler crane, the rebar bar 100 in a reduced state is hung on the lifting device 2 such as a winch provided on the mounting base 1.

As shown in FIG. 5B, a band member (not shown) that binds the rebar rod 100 in a contracted state after the reduced rebar rod 100 is hung on the lifting device 2 of the mounting base 1. Is removed and the reinforcing bar 100 is extended.
Next, as shown in FIG. 5C, the reinforcing bar 100 is lowered into the pile hole H by the lifting device 2 while the reinforcing bar 100 is extended.
And as shown in FIG.5 (d), if the reinforcement rod 100 is extended to the design length and the U-shaped fixing | fixed part 11 of the lower end part of the reinforcement rod 100 reaches the vicinity of the bottom face of the pile hole H, The building of the reinforcing bar 100 is substantially finished.
After the lower end portion (U-shaped fixing portion 11) of the reinforcing bar rod 100 reaches the vicinity of the bottom surface of the pile hole H, the upper end portion 12 of the reinforcing bar rod 100 is installed in the upper opening of the pile hole H by a conventionally known procedure. The construction of the reinforcing bar 100 is completed by removing the built-in mount 1 by replacing with steel (not shown).
And a cast-in-place pile can be constructed by placing concrete in the pile hole H in which the reinforcing bar 100 is built.

Thus, if the U-shaped fixing part 11 in which the flexible reinforcing bar 10 is connected in a convex U-shape is provided at the lower end of the reinforcing bar 100, the adhesion strength of the reinforcing bar 100 is increased. Can do.
In particular, the U-shaped fixing unit 11 forms the flexible reinforcing bar 10 in a U-shape in advance so that one flexible reinforcing bar 10 is folded at the lower end of the reinforcing bar 100 when the reinforcing bar 100 is manufactured at the factory. Since it can be easily formed by bending, it is an effective technique as a structure for easily increasing the adhesion strength of the reinforcing bar 100.
In addition, when manufacturing the reinforcing bar 100 at the factory, the U-shaped fixing portion 11 can be easily formed by connecting the lower ends of the two flexible reinforcing bars 10. Even the letter-shaped fixing part 11 is an effective technique as a structure for easily increasing the adhesion strength of the reinforcing bar 100.

  As described above, since the reinforcing bar 100 of the present embodiment includes the U-shaped fixing part 11 at the lower end, the vertical supporting force in the pulling direction of the reinforcing bar 100 is increased, and the adhesion strength of the reinforcing bar 100 is increased. Can do.

  In the embodiment described above, the eight flexible reinforcing bars 10 that are apparently arranged along the longitudinal direction of the reinforcing bar 100 make a pair, and four U-shapes are formed at the lower end of the reinforcing bar 100. Although the case where the fixing unit 11 is formed has been described as an example, the present invention is not limited to this, and among the plurality of flexible rebars 10, at least one pair is connected so as to exhibit a U shape, It may be a reinforcing bar 100 in which at least one U-shaped fixing part 11 is formed.

Further, the number of the flexible reinforcing bars 10 in the reinforcing bar rod 100 is arbitrary, and the number may be appropriately adjusted according to the size of the reinforcing bar rod 100.
If the number of flexible reinforcing bars 10 is an odd number, it goes without saying that there are flexible reinforcing bars 10 that are not involved in the formation of the U-shaped fixing portion 11.

  In addition, it is needless to say that other specific detailed structures can be appropriately changed.

DESCRIPTION OF SYMBOLS 1 Built-in stand 2 Lifting device 3 Construction machine 4 Band reinforcement winding device 5 Band reinforcement winding stand 6 Lowering device 7 Built-in stand 8 Drum device 10 Flexible rebar 11 U-shaped fixing part 12 Upper end part 13 Lower frame 14 Upper frame 20 Band reinforcement 100 Reinforcement rod H Pile hole

Claims (6)

A rebar rod having a plurality of flexible rebars arranged at appropriate intervals in the circumferential direction and one or a plurality of strips wound around the plurality of flexible rebars,
A reinforcing bar rod having a structure in which at least a pair of the plurality of flexible reinforcing bars is connected so as to form a convex U-shape downward at a lower end portion of the reinforcing bar rod.   The rebar rod according to claim 1, wherein the flexible rebar having a U-shape at the lower end of the rebar rod is formed by bending one flexible rebar.   The reinforcing bar rod is configured to be deformable into a structure in which the plurality of flexible reinforcing bars along the longitudinal direction thereof are bent into an arc shape and deformed in a spiral shape, and the length thereof is shortened and reduced. The reinforcing bar rod according to claim 1 or 2. Reinforcing bar erection method of building a reinforcing bar rod having a plurality of flexible reinforcing bars arranged at appropriate intervals in the circumferential direction and a band rod wrapped around the plurality of flexible reinforcing bars in a pile hole,
A step of installing at least one set of drum devices each wound around both ends of the flexible rebar in an arrangement sandwiching the pile holes;
Feeding each of the flexible rebars from the set of drum devices and feeding a portion of the flexible rebar bent downward in a convex U-shape into the pile hole between the set of drum devices;
Winding a band around a plurality of flexible rebars fed into the pile hole;
A method of erection of a reinforcing bar rod, comprising:   5. The reinforcing bar erection method according to claim 4, wherein a flexible rebar having a length corresponding to at least the depth of the pile hole is wound around the set of drum devices in advance. Reinforcing bar erection method of building a reinforcing bar rod having a plurality of flexible reinforcing bars arranged at appropriate intervals in the circumferential direction and a band rod wrapped around the plurality of flexible reinforcing bars in a pile hole,
The flexible rebar is bent in a U-shape projecting downward at the lower end of the rebar bar, and the flexible bar is removed by spiraling the flexible bar excluding the U-shaped part; and
Extending the reinforcing bar rod from the top of the pile hole into the pile hole while returning the spiral portion of the flexible reinforcing bar in the reduced size of the reinforcing bar to a straight line; and
A method of erection of a reinforcing bar rod, comprising:

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