JPH1054110A - Connecting structure of reinforcement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connecting structure where a reinforcement can be easily connected correspondingly to the actual state of an execution field. SOLUTION: In this connecting structure, the tip parts of reinforcements 1, 2 to be butt-connected are mutually opposite, and tapered wedges 3, 4 are fitted to the outer periphery of each tip part, and each of wedges 3, 4 is embracedly held with the first and the second coupler 5, 6, which are mutually joined through a screw mechanism and connected. Tapered parts 5b, 6b are severally formed in the inner periphery of each of couplers 5, 6, and the couplers 5, 6 are mutually fastened to make force act on themselves so that the inner peripheries of wedges 3, 4 may gnaw into the reinforcement for enlarging frictional force. Thus the reinforcements 1, 2 are cut to required length at an execution site, and can be connected with the tips set mutually opposite, and therefore can be executed without special preparations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rebar connecting structure in which deformed rebars used in construction sites such as civil engineering and construction are joined together by a mechanical structure.

[0002]

2. Description of the Related Art As means for butt-connecting deformed reinforcing bars used in construction sites such as civil engineering and construction, welding by various welding methods and so-called mechanical joints utilizing screw mechanisms have been adopted.

As shown in FIG. 6, a mechanical joint includes a sleeve 62 having a female thread 62a at an end of a deformed reinforcing bar 61 in advance.
At the construction site, at the construction site, a connection bolt 63 is formed by engraving a male screw portion 63a over the entire length of the female screw portion.
Is screwed, and a sleeve 65 fixed to the end of the other deformed reinforcing bar 64 to be connected to the connection bolt is screwed and connected.

As a method of screwing the other sleeve 65 into the connection bolt 63, first, the sleeve 62 of one rebar is used.
Is screwed in advance to about half of the length. Next, centering is performed by aligning the female thread 65 a of the sleeve 65 of the other reinforcing bar 64 with the tip of the connection bolt 63. Further, the other reinforcing bar 64 to be connected is screwed by rotating it to connect the sleeves.

In the case where the above method cannot be adopted at a construction site, the female thread of one of the sleeves is lengthened, and a connection bolt in which two nuts are screwed is screwed deeply. Then, a connection method is adopted in which the female thread of the sleeve of the other reinforcing bar is aligned, the connection bolt is unscrewed, and this is connected to the sleeve of the other reinforcing bar. In this case, each nut is fastened to the end of the sleeve with a predetermined torque to prevent the connection bolt from loosening.

[0006]

In the above-mentioned prior art, a connecting sleeve is previously fixed to each end of a reinforcing bar to be butt-connected. Therefore, at the construction site, only turning the reinforcing bar or the connecting bolt is required. It is characterized in that it can be connected with the.

However, at the construction site, it is not always possible to adopt the above-described joint structure of a reinforcing bar, and the length of the reinforcing bar to be connected may not be suitable for connecting. In such a case, the rebar is cut to an appropriate length at the construction site and then joined by welding, etc., but the welding work requires equipment and work skills at the construction site and raises construction costs. was there.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the construction cost by making it possible to easily perform butt connection of reinforcing bars in accordance with the actual situation at the construction site.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method of cutting a reinforcing bar to be butt-connected at a construction site into a length suitable for connecting the reinforcing bars, and wedges the two with a wedge. It is connected by a coupler that holds the wedge and supports an axial tensile load. Here, the coupler includes a first coupler having a male thread portion and a second coupler having a female thread portion, and refers to a type of mechanical joint that butt-connects rebars by screwing the male thread portion and the female thread portion.

The wedge has an outer periphery and a circumference formed in an arc shape concentric with the central axis of the reinforcing bar, and the outer periphery is formed by combining a plurality of wedge pieces each formed in a tapered shape having a larger tip end side. Consisting of Each wedge has the larger diameter aligned with the tip of the rebar and is attached so as to surround the rebar.

[0011] In the wedge mounting described above, one wedge is held by an inner peripheral taper portion formed on the inner periphery of the first coupler which is loosely fitted to one rebar. Similarly, the wedge attached to the other reinforcing bar is held by an inner peripheral taper formed on the inner periphery of the second coupler.

The above-mentioned first coupler is formed of a cylindrical body, and a male thread is provided on the outer periphery of the cylindrical body, and the inner peripheral taper for increasing the inner diameter of the distal end is provided on the distal end side of the inner periphery. A part is formed. In addition, a region other than the above-described inner peripheral taper portion on the inner periphery of the cylindrical body is a parallel hole portion into which the above-described rebar can be loosely fitted. The first coupler is displaceable by inserting a reinforcing bar through the parallel hole.

On the other hand, the above-mentioned second coupler has a first coupler.
The coupler is formed of a cylindrical body having a larger diameter than the cylindrical body of the coupler, and a female thread portion capable of being screwed with the external thread portion of the first coupler is provided in a predetermined length range from the distal end portion of the inner periphery to be screwed. This makes it possible to couple both couplers. On the inner side of the inner periphery following the female thread portion, the above-mentioned inner peripheral taper portion which can contact the outer peripheral taper portion of the wedge is formed. A range from the rear end portion of the inner peripheral taper portion to the rear end portion of the cylindrical body is a parallel hole portion into which a reinforcing bar can be loosely fitted, so that the second coupler can be displaced along the other reinforcing bar.

In the butt connection of the reinforcing bars, first, each coupler is loosely fitted to each reinforcing bar, and the ends of the reinforcing bars are brought into contact with each other.
Temporarily fix the wedge to each tip. Next, when each coupler is approached, the external thread portion and the internal thread portion are screwed together and displaced in a direction to make the taper portions approach each other, and the inner peripheral taper portion of each coupler goes toward the central axis with the outer taper portion of each wedge The force acts in the direction, causing the wedge to enter the rebar, increasing the frictional force in the axial direction. This frictional force increases when a force acts in a direction (axial direction) in which the rebars separate from each other, and both rebars are connected via a coupler.

[0015]

Next, an example of an embodiment of the present invention will be described. As shown in FIG. 1, the coupler of the present invention comprises a pair of deformed reinforcing bars 1 and 2 to be butt-connected.
A pair of wedges 3 and 4 protruding from both ends of the first and second couplers, and a first coupler 5 and a second coupler 6 respectively holding these wedges so as to be pressed against the respective rebars.

The first coupler 5 and the second coupler 6 are connected by a screw mechanism, and a mechanism is employed in which the wedges 3 and 4 press the outer periphery of the rebar by screwing the couplers in a direction of approaching each other. is there. By supporting the wedges 3 and 4 with the couplers 5 and 6, the pulling force acting on the rebars 1 and 2 is supported.

FIG. 2 shows the shape of the wedge, but since both wedges are the same, only the wedge 3 located on the left side of FIG. 1 will be described here. As shown in the figure, a pair of wedge pieces 3a are formed by dividing a cylindrical body having a tapered outer periphery into two along the center line in the axial direction. The radius of curvature of the inner peripheral surface 3b of the cylindrical body matches the radius of the reinforcing bar 1 to be connected, and the outer peripheral surface is an outer tapered portion 3c formed in a tapered shape at a predetermined angle. A concave portion 3e for increasing frictional resistance in the axial direction when pressed is preferably formed on the inner peripheral surface 3a.

The opposing surfaces of each of the wall portions along the dividing line of the cylindrical body are cut off by a predetermined thickness to provide a gap 3d for enabling adjustment of the gap therebetween. Since a large load acts on the wedge, tool steel that has been subjected to heat treatment such as quenching and tempering is used to withstand this. In this example, two wedge pieces are used, but in some cases, it is possible to use three or four wedge pieces.

FIG. 3 shows the first coupler 5, which is formed by cutting a round bar of structural steel into a cylindrical body as shown. A threaded portion 5a is formed by rolling in a range of a position approximately half the length from the front end of the outer peripheral portion of the cylindrical body. The external thread portion 5a is formed of a metric coarse thread conforming to Japanese Industrial Standard (JIS).

In the range from the front end (right side) of the inner periphery of the cylindrical body to a position substantially half the length, an inner peripheral taper portion 5b formed in a tapered shape for increasing the inner diameter of the front end portion is formed. is there. The taper angle of the inner peripheral taper portion 5b is desirably equal to the taper angle of the outer taper portion 3c of the wedge 3. The range from the inner end of the inner peripheral taper portion 5b to the rear end (left end) of the cylindrical body is slightly larger than the outer diameter of the reinforcing bar 1 so that the parallel hole 5c allows the reinforcing bar to be loosely fitted.
Is provided.

FIG. 4 shows the second coupler 6,
Like the first coupler 5, it is formed by cutting a round bar of structural steel into a predetermined length and processing it into a cylindrical body as shown.
The outer diameter and the length of the cylindrical body constituting the second coupler 6 are slightly larger than those of the first coupler 5, and the inner peripheral portion on the front end side (the left side in FIG. 4) has a length from the front end. Almost a third
The female screw portion 6a is engraved in the range of. Female thread 6a
Can be screwed with the external thread 5a (see FIG. 3) of the first coupler, and this external thread is engraved by machining such as tapping. A second inner peripheral taper formed in a range corresponding to approximately half the length of the cylindrical body from the inner end of the internal thread portion 6a so as to be in contact with the outer tapered portion of the wedge 4. A part 6b is provided. The inner peripheral portion following the rear end of the inner peripheral tapered portion 6b is a parallel hole portion 6c having an inner diameter slightly larger than the outer diameter of the reinforcing bars 1 and 2.

Next, the connection procedure and operation will be described.
The present invention is mainly applied to the case where the connection is made while adjusting the length of the reinforcing bar at the construction site. Therefore, it is convenient to adopt this method when it is difficult to adopt the means by the connection structure as described in the related art.

First, the lengths of the reinforcing bars 1 and 2 are cut at the construction site, and adjusted to be suitable for the reinforcing bar structure.
Next, the first coupler 5 is inserted into one of the reinforcing bars 1 to be butt-connected, and the second coupler 6 is inserted into the other reinforcing bar 2, so that the tips of both the reinforcing bars are brought into contact with each other (see FIG. 1).

Next, wedges 3 and 4 are temporarily fixed to the respective distal ends of the rebars 1 and 2 so that the side having the larger outer periphery faces the wedges 3 and 4. The temporary fixing is performed, for example, by applying an adhesive to the inner peripheral portion, or by winding an elastic band around a position that does not hinder the mounting of the coupler.

Next, the first coupler 5 is moved toward the tip of one of the rebars 1, and the inner peripheral taper 5b is brought into contact with the outer peripheral taper 3a of the wedge so that the wedge is oriented toward the center of the rebar. And pressed. Next, the second coupler 6
Is moved toward the tip of the other reinforcing bar 2, and similarly, the inner peripheral tapered portion 6 b is brought close to the first coupler 5 in a state of contact with the outer peripheral tapered portion 4 a of the wedge, and the female screw portion 6 a
With the male thread portion 5a of the first coupler. Due to the screwing, the outer peripheral tapered portions 3a and 4a of the wedge are pressed by the inner peripheral tapered portions 5b and 6b of the respective couplers, and the frictional force in the axial direction when a tensile force acts on the reinforcing bar increases. Therefore, in order to obtain a large frictional force, it is necessary to turn the coupler with a large torque. In this case, the two couplers 5 and 6 are connected by tightening the screw portions using a hydraulic torque wrench. Like that. By combining both couplers 5, 6, both reinforcing bars 1,
2 is connected via wedges 3 and 4 and both couplers 5 and 6.

When a tensile force acts between the reinforcing bars 1 and 2,
For example, the reinforcing bar 1 attempts to move to the left in FIG. 1 together with the wedge 3, and the pressing force acting between the outer peripheral tapered portion 3a of the wedge and the inner peripheral tapered portion 5b of the first coupler in the Y direction (vertical direction on the paper). A component force is generated, and the frictional force between the reinforcing bar 1 and the wedge 3 increases due to the pressing force. This frictional force is correspondingly greater as the tensile force is greater, and the situation where the rebar slips out of the space between the wedges does not occur. The component force in the X direction (horizontal direction in FIG. 1) of the pulling force on the rebars 1 and 2 is obtained through the contact between the outer tapered portions 3a and 4a of each wedge and the inner tapered portions 5b and 6b of each coupler. Paid by each coupler. Since the coupling between the couplers 5 and 6 is based on the coupling force between the male screw portion 5a and the female screw portion 6a, a stronger coupling force is obtained as the number of screw threads to be screwed is larger.

Next, another example of the embodiment of the present invention will be described.

In the structure of this embodiment, as shown in FIG. 5, a pair of reinforcing bars 11 and 12 to be butt-connected is connected.
Flanges 11a and 12a are provided in advance at each of the front ends, and wedges 13 and 14 are attached to the inside of these flanges in a state where the front ends are in contact with each other, and these wedges are connected to the first coupler 15 or the first coupler 15a. It is held by two couplers 16. The tensile force acting between the rebars is supported by the connection between the external thread portions 15a and the internal thread portions 16a. Since high processing accuracy is not required for the tapered portion and the tapered portion only needs to be provided on the wedge, the manufacture of both couplers is facilitated and the coupler can be adopted as a means for reducing the manufacturing cost.

[0029]

EXAMPLE Next, as one example, specific dimensions of each part of a rebar connecting structure used for connecting a rebar having a nominal diameter of D25 (diameter of 27 mm) will be presented. Assuming that the wedge 3 is not divided, the inner diameter is 27 mm, the maximum outer diameter is 46 mm, and the outer peripheral taper 3c is formed to have a taper of 1/5. The entire length of the wedge is 40 mm, and a groove for increasing the frictional force is appropriately formed in the inner peripheral portion. The gap 3a between the divided surfaces of the wedge pieces 3b is 6 mm (see FIG. 2). Each wedge piece 3a is machined, quenched,
Tempered heat treatment for strengthening.

The first coupler 5 has a diameter of 52 mm and a length of 60 mm.
mm and a length of 3 mm from the tip (right side in FIG. 3).
The screw portion 5a is engraved in a range of 0 mm. The external thread portion 5a employs a metric coarse thread M52 specified in JIS. An inner peripheral tapered portion 5b is provided in a range of a depth of 30 mm from the front end of the inner peripheral portion to be able to abut against the outer peripheral tapered portion 3a of the wedge 3. The inner peripheral portion has a rear end portion (see FIG. 3 left) parallel hole 5 with a diameter of 30 mm
c.

The second coupler 6 is formed of a cylindrical body having a diameter of 65 mm and a length of 80 mm, and is provided on the front end side of the circumferential portion (FIG. 4).
On the left side), a female screw portion 6b formed by engraving a female screw that can be screwed with the male screw portion 5a of the first coupler is provided in a range of a depth of 26 mm. An inner peripheral taper portion 6 formed with a taper capable of contacting the outer taper portion 3a of the wedge 4 within a range of a length of 40 mm from the inside of the inner end portion of the female screw portion 6b.
b. The maximum diameter of the inner peripheral tapered portion 6b is 47 mm at the boundary with the female screw portion 6a. Therefore, a step is formed between the female screw portion 6a and the inner peripheral taper portion 6b. The inner peripheral portion continuing from the rear end of the inner peripheral tapered portion 6b to the rear end of the cylindrical body (the right end in FIG. 4) is a parallel hole 6c having an inner diameter of 30 mm.

[0032]

According to the present invention, the connecting members are not fixed at the factory in advance as in the prior art, but are butt-connected by connecting them at the construction site. Flexible connection according to the actual situation becomes possible. For example, if it is not possible to arrange the reinforcing bar with the sleeve in the conventional technology in time or if it becomes necessary to adjust the length of the reinforcing bar at the construction site, adjust the length of the reinforcing bar on the spot. In addition, by applying the connection structure according to the present invention, it is possible to easily connect the reinforcing bars.

In addition, since the respective structural members are connected via the tapered portion, and the structure can be supported with a larger force as the tensile force acting between the reinforcing bars increases, the structure can be simplified with a simple structure. There is an effect that a proper connection is obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 shows the shape of a wedge, (a) is a side view,
(B) is a sectional view.

3A and 3B show the shape of a first coupler, wherein FIG. 3A is a cross-sectional view and FIG. 3B is a side view.

FIG. 4 is a cross-sectional view illustrating a shape of a second coupler.

FIG. 5 is a sectional view showing another example of the embodiment of the present invention.

FIG. 6 is a partially cutaway sectional view showing a conventional technique.

[Explanation of symbols]

 1, 2 Reinforcing bar 3, 4 Wedge 3c Outer peripheral taper part 5 First coupler 6 Second coupler 5a Male thread part 6a Female thread part 5b, 6b Inner peripheral taper part 5c, 6c Parallel hole part

Claims (1)

[Claims] 1. A pair of rebars with their respective tips facing each other, a wedge attached so as to surround each of the tips of the respective rebars with the tips facing each other, and one of the reinforcing bars. The first which is loosely fitted and holds one of the wedges
A second coupler that loosely fits the other rebar and holds the other wedge, the wedge having an outer periphery and an inner periphery formed in an arc shape concentric with the center axis of the rebar. The outer peripheral portion is formed of a plurality of wedge pieces provided with an outer peripheral tapered portion formed in a tapered shape that enlarges the tip end side. The first coupler is provided on the outer peripheral portion of the cylindrical body. A second external thread portion, an inner peripheral taper portion formed in the inner peripheral portion so as to increase the inner diameter of the distal end portion, and a parallel hole portion provided subsequent to the inner peripheral taper portion; The coupler has a female thread portion engraved on the inner peripheral portion within a predetermined length from the front end portion, and an inner diameter at the front end portion within a predetermined length range from the inner end portion to the rear end portion of the female thread portion. An inner peripheral taper portion formed to be larger, and provided following the inner peripheral taper portion. A threaded portion of the first coupler and a female thread of the second coupler, the inner peripheral taper portions are brought closer to each other, and the outer periphery of each rebar is attached to each wedge. A connecting structure for reinforcing bars, wherein the reinforcing bars are butt-connected to each other by generating a pressing force.