JP7026501B2 - Reinforcing bar joints - Google Patents

Description

The present invention relates to a joint connecting two reinforcing bars.

Two reinforcing bars are connected via a tubular joint. For example, in a joint that is connected by screwing, a female thread is formed on the inner circumference of the joint, and by screwing threaded reinforcing bars (reinforcing bars having threaded joints at equal pitches) from both ends of the joint, two threads are formed. The screw reinforcing bars are connected. In this connected state, the grout material is filled in the gap between the joint and the threaded reinforcing bar to eliminate the backlash between the two.

In order to secure sufficient connection strength between the threaded reinforcing bar and the joint, the insertion depth of each threaded reinforcing bar into the joint needs to be a predetermined amount or more. Therefore, conventionally, marking extending in the longitudinal direction is applied to a position away from the tip of the threaded rebar with a paint or the like to serve as a guideline for the insertion depth of the threaded rebar. However, the work of marking has to be applied or sprayed with a jig or the like, which requires a lot of manpower and is very troublesome. In addition, there is a risk of construction defects due to human error such as marking errors.

The joint disclosed in Patent Document 1 has an elongated oval confirmation window formed in the central portion in the axial direction. Through this confirmation window, it is possible to visually check the butt spacing between the two reinforcing bars screwed into the joint. Thereby, it can be confirmed that the two reinforcing bars are inserted into the joint at a predetermined depth or more. After confirming the insertion depth of the reinforcing bar, a cap made of a transparent elastic resin is fitted into the confirmation window and brought into close contact with the outer periphery of the tip of each reinforcing bar. Grout material is injected into the inside of the joint from the injection port formed in this cap.

When the joint of Patent Document 1 is used, even after the grout material is hardened, the butt gap between the two reinforcing bars can be visually recognized through the transparent cap that is in close contact with the outer periphery of the reinforcing bars, and the insertion depth of the reinforcing bars can be visually recognized. It is possible to reconfirm.

Utility Model Registration No. 3165895 Gazette

In Patent Document 1, it was necessary to form a cap, which is a separate component, with a transparent resin in addition to the joint. In addition, the adhesion of the cap to the outer circumference of the reinforcing bar is unstable, and when the grout material enters between the cap and the outer circumference of the reinforcing bar due to the injection pressure, the butt interval of the reinforcing bar cannot be visually observed due to this grout material, and the grout material is injected. Later, it may not be possible to reconfirm the insertion depth of the reinforcing bar.

In order to solve the above problems, the present invention is a joint in which two reinforcing bars are connected by using a grout material, has a tubular shape, and one reinforcing bar is inserted and connected so as to be penetrateable from the tip in the axial direction. It is provided with a first connecting portion to be formed, and a second connecting portion having a tubular shape and having the other reinforcing bar inserted and connected so as to be penetrateable from the tip in the axial direction. In the cylinder walls of the first and second connecting portions, injection holes for filling the grout material between the cylinder wall and the inserted reinforcing bar at an intermediate position between the tip and the base in the axial direction, respectively. Is formed. Between the base end portion of the first connecting portion and the base end portion of the second connecting portion, the bridge portions that bridge the first and second connecting portions in a separated state are the first and first bridge portions. A plurality of two connecting portions are provided at intervals in the circumferential direction. The gap between the plurality of bridge portions exposes the tip portions of the one and the other reinforcing bars that have penetrated the first and second connecting portions, respectively.

According to the above configuration, the tips of the two reinforcing bars penetrating the first and second connecting portions are abutted between the separated first connecting portion and the second connecting portion. The butt spacing at the tips of these reinforcing bars can be visually recognized from the gaps between the plurality of bridge portions. Since the grout material is filled inside the first and second connecting portions and not between the first connecting portion and the second connecting portion, the butt spacing between the two reinforcing bars is maintained even after the grout material is injected. It can be visually recognized, and the insertion depth of the reinforcing bar can be reconfirmed without fail.

Preferably, the plurality of bridge portions are provided at equal intervals.
According to the above configuration, the gaps in which the butt gap between the two reinforcing bars can be visually recognized are dispersedly formed, and the insertion depth of the reinforcing bars can be confirmed from a wide direction.

Preferably, female threads for screwing the threaded reinforcing bars are formed on the inner peripheral surfaces of the first and second connecting portions, and the reinforcing bars inserted into the first and second connecting portions are threaded reinforcing bars.
According to the above configuration, since the screw reinforcing bars are connected to the first and second connecting portions by screwing, the connection of the reinforcing bars can be further strengthened.

Preferably, a sealing member made of an elastic material is provided on the inner peripheral surface of the cylinder wall at the base end portion and the tip end portion of the first connecting portion and the base end portion and the tip end portion of the second connecting portion. It is provided so as to project inward in the radial direction from the.
According to the above configuration, the seal member can hold the grout material injected into the first and second connecting portions.

According to the present invention, in the reinforcing bar joint, the butt spacing of the reinforcing bars can be reliably visually recognized even after the grout material is filled, and the insertion depth of the reinforcing bars can be reliably reconfirmed.

It is a perspective view of the joint which concerns on 1st Embodiment of this invention. (A) It is a front view of the joint. (B) It is a right side view of the joint. (A) It is a vertical end view along the line IIIA-IIIA of FIG. 2 (B). (B) It is an end view along the line IIIB-IIIB of FIG. 2A. (C) is an end view taken along the line IIIC-IIIC of FIG. 2 (A). It is a figure which shows the procedure of connecting the reinforcing bar to the joint in the order of process, (A) is the vertical sectional view along the IV-IV line of FIG. A vertical cross-sectional view showing a state in which a reinforcing bar is screwed, and (C) is a vertical cross-sectional view showing a state in which the joint is filled with a grout material. It is a front view which shows the state which two reinforcing bars are screwed into the joint. A joint according to a second embodiment of the present invention, (A) is a right side view, and (B) is a vertical sectional view taken along the line VIB-VIB of FIG. 6 (A). (A) It is a vertical sectional view showing a state in which two reinforcing bars are inserted into the joint. (B) It is a vertical sectional view which shows the state which the grout material is filled in the said joint.

[First Embodiment]
Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 5. In this embodiment, the present invention is applied to a joint for a threaded reinforcing bar. The joint 1 used in this embodiment includes a first connecting portion 11, a second connecting portion 12, and a plurality of bridge portions 13 bridged between the base end portions thereof. The joint 1 is made of cast iron integrally molded by casting.

The first connecting portion 11 has a tubular shape and has openings 11a and 11b at its tip and base, respectively. The outer peripheral shape of the cylinder wall of the first connecting portion 11 is circular, and a female screw 11c for screwing the screw reinforcing bar 2 is formed on the inner circumference thereof. A screw reinforcing bar 2 is inserted from the opening 11a on the tip side by screwing and can penetrate the first connecting portion 11. A circular injection hole 11d for injecting the grout material 3 is formed in the axial center of the cylinder wall of the first connecting portion 11 and penetrates the cylinder wall. The tip of a nozzle of a grout injection jig (not shown) is inserted into the injection hole 11d.

The second connecting portion 12 has the same shape as the first connecting portion 11, has a tubular shape, and has openings 12a and 12b at its tip and base end. The opening 12b on the proximal end side is arranged coaxially with the opening 11b on the proximal end side of the first connecting portion 11 and faces each other in a separated state. The outer peripheral shape of the cylinder wall of the second connecting portion 12 is circular, and a female screw 12c is formed on the inner circumference thereof. A screw reinforcing bar 2 is inserted from the opening 12a on the tip side by screwing and can penetrate the second connecting portion 12. A circular injection hole 12d for injecting the grout material 3 is formed in the axial center of the cylinder wall of the second connecting portion 12, and penetrates the cylinder wall. The injection hole 12d and the injection hole 11d of the first connecting portion 11 are arranged in a straight line along the longitudinal direction of the joint 1.

The bridge portion 13 is bridged between the base end portion of the first connecting portion 11 and the base end portion of the second connecting portion 12, which are separated from each other. In this embodiment, four bridge portions 13 are provided and are arranged at equal intervals in the circumferential direction of the joint 1. Each bridge portion 13 extends in the axial direction of the joint 1 and has base portions 13a and 13a at both ends and a connecting portion 13b between them. The base portions 13a and 13a are connected to the base end portion of the first connecting portion 11 and the base end portion of the second connecting portion 12, respectively, and are connected to the base end portion from the tip end side of the first and second connecting portions 11 and 12, respectively. It is inclined so as to proceed outward in the radial direction of the joint 1 toward the side. The connecting portion 13b has a substantially constant wall thickness over the entire length. A gap 14 is formed between the adjacent bridge portions 13, so that the inside of the joint 1 can be visually recognized.

A case where a pair of threaded reinforcing bars 2 are connected to the joint 1 having the above configuration will be described with reference to FIG. First, the joint 1 is screwed into one of the threaded reinforcing bars 2 from the tip of the first connecting portion 11 and screwed over the entire length of the joint 1. In this state, the other threaded reinforcing bars 2 are arranged on the same straight line, and the end faces of the threaded reinforcing bars 2 are brought into contact with each other or brought close to each other. After that, the joint 1 is turned to screw the second connecting portion 12 into the other threaded reinforcing bar 2 as shown in FIG. 4 (B). The joint 1 may be first screwed from the tip of the second connecting portion 12 to the other threaded reinforcing bar 2 and then screwed over the entire length of the joint 1. Further, in a state where the first connecting portion 11 is half screwed to one threaded reinforcing bar 2, the other threaded reinforcing bar 2 may be turned and screwed to the second connecting portion 12.

Next, it is confirmed whether or not the tip portions 2a of both screw reinforcing bars 2 can be seen by looking through the gap 14 of the joint 1. As shown in FIG. 5, if the tip portions 2a of both threaded reinforcing bars 2 can be visually recognized from the gap 14, it is determined that both threaded reinforcing bars 2 are screwed into the joint 1 with the required insertion depth secured. Then, move on to the next grout injection process. If both or one of the threaded reinforcing bars 2 cannot be seen from the gap 14, it is determined that the required insertion depth has not been reached, and the invisible threaded reinforcing bar 2 is screwed until the tip portion 2a can be visually recognized from the gap 14. Proceed.

When the screwing is completed, the tip of the nozzle of the injection jig (not shown) is applied to the injection holes 11d and 12d, and the grout material 3 such as cement milk or a filler-filled epoxy resin is injected. As shown in FIG. 4C, the grout material 3 is filled between the inner circumferences of the first and second connecting portions 11 and 12 and the outer circumference of the reinforcing bar 2. When the grout material 3 leaks from the openings 11a and 11b of the first connecting portion 11 and the openings 12a and 12b of the second connecting portion 12, the injection of the grout material 3 is stopped. By hardening the grout material 3, the two threaded reinforcing bars 2 are firmly connected to the first connecting portion 11 and the second connecting portion 12 of the joint 1, and eventually the two threaded reinforcing bars 2 are firmly connected to each other.

In the joint 1 having the above configuration, since the grout material 3 is not filled between the first connecting portion 11 and the second connecting portion 12, the first and second grout materials 3 are not filled even after the grout material 3 is injected into the joint 1. The tip portion 2a of the threaded reinforcing bar 2 can be visually observed from the gap 14 between the plurality of bridge portions 13 bridged between the connecting portions 11 and 12.
If it becomes necessary to reconfirm the insertion depth of the threaded reinforcing bar 2 in the joint 1 before placing concrete, the screw can be screwed by visually recognizing the butt interval of the tip of the threaded reinforcing bar 2 exposed from the gap 14. It can be reconfirmed that the insertion depth of the reinforcing bar 2 is at least a predetermined value. Since the four bridge portions 13 are arranged at equal intervals in the circumferential direction of the joint 1, the gaps 14 are dispersedly formed so that the inside of the joint 1 can be visually observed from almost any direction. There is.

The joint 1 having the above configuration is particularly useful for reconfirming the insertion depth of the reinforcing bar at the bar arrangement site where a large number of joints are arranged.
In the conventional joint, even if the butt spacing of the reinforcing bars cannot be visually recognized in a dim environment such as in the evening due to the limited size of the confirmation window, in the joint 1 having the above configuration, the separated first and first Since the two exposed reinforcing bars 2 are visually observed from between the second connecting portions 11 and 12, it is easy to visually recognize the butt interval of the reinforcing bars 2, and by extension, it is easy to confirm the insertion depth of the reinforcing bars 2.
Further, in the conventional joint, even if it is necessary to look into the confirmation window so as to go around the joint in order to visually recognize the butt interval of the reinforcing bar depending on the direction of the confirmation window at the bar arrangement site, the above configuration is used. In the joint 1, the plurality of gaps 14 where the tip portions 2a of the two reinforcing bars 2 are exposed are formed at equal intervals in the circumferential direction of the joint 1, so that the butt spacing of the reinforcing bars 2 can be visually recognized from a wide range.
Further, as compared with the elongated confirmation window of the conventional joint, the gap 14 of the joint 1 having the above configuration is formed by the adjacent bridge portion 13 and the base ends of the first and second connecting portions 11 and 12. The opening area can be made large, and the butt interval can be visually recognized from a greater distance.

Next, another embodiment of the present invention will be described. Regarding the following embodiments, only configurations different from those of the above embodiments will be described, and the same components will be designated by the same reference numerals and the description thereof will be omitted.

[Second Embodiment]
6 and 7 show the joint according to the second embodiment of the present invention. The joint of this embodiment is a sleeve type joint in which female threads are not formed on the inner circumferences of the first and second connecting portions.
An annular accommodating groove 11e is formed on the inner circumferences of both ends of the first connecting portion 11, and an annular accommodating groove 12e is formed on the inner circumferences of both end portions of the second connecting portion 12.
A seal member 4 is mounted on the accommodating grooves 11e and 12e.

The seal member 4 is made of rubber (elastic body). The seal member 4 has two film portions 41. The film portion 41 has a thin disk shape having a hole 41a in the center. When one reinforcing bar 2 is inserted into the first connecting portion 11 and the other reinforcing bar 2 is inserted into the second connecting portion 12, the membrane portion 41 is elastically deformed into the reinforcing bar 2 so that the hole 41a of the membrane portion 41 expands in diameter. In close contact. As shown in FIG. 7, when the grout material 3 is injected into the inside of the first and second connecting portions 11 and 12 from the injection holes 11d and 12d, the grout material 3 is introduced into the inside of the connecting portions 11 and 12 by the sealing member 4. Can be retained. As a result, leakage of the grout material 3 can be prevented until the grout material 3 is cured.

The present invention is not limited to the above embodiment, and various modifications can be adopted without departing from the gist thereof.
In the above embodiment, four bridge portions are provided, but the number of bridge portions may be two or three, or five or more.
In the above embodiment, the bridge portions are arranged at equal intervals in the circumferential direction of the joint so that the gaps are formed at equal intervals. However, the arrangement of the bridge portions is biased to form gaps of different widths. May be done. This makes it easier to see the inside of the joint from a specific direction.
In the above embodiment, the joint is formed by casting, but it may be formed by metal processing of steel.
In the above embodiment, the joint is integrally formed, but the first and second connecting portions may be formed separately and the bridge portion may be joined to them by welding.
The seal member of the second embodiment may be provided on the joint of the first embodiment.
In the second embodiment, instead of the threaded reinforcing bar, a normal deformed reinforcing bar having vertical ribs and horizontal edges may be used.
The cross-sectional shape of the outer periphery of the first and second connecting portions may be formed into a polygon such as a hexagon.
A conventional method of marking a reinforcing bar may be used in combination with the joint of the above embodiment.

The present invention can be applied to a joint connecting two reinforcing bars.

1 Fitting 2 Threaded Rebar (Reinforcing Bar)
2a Tip of threaded rebar 3 Grout material 4 Sealing member 11 1st connecting part 11c Female thread 11d Injection hole 12 2nd connecting part 12c Female thread 12d Injection hole 13 Bridge part 14 Gap

Claims (6)

A joint that connects two reinforcing bars using grout material.
The first connecting part, which has a tubular shape and is connected by inserting one of the reinforcing bars so that it can penetrate from the tip in the axial direction,
A second connecting part that has a tubular shape and is connected by inserting the other reinforcing bar so that it can penetrate from the tip in the axial direction.
Equipped with
Injection holes for filling grout material between the cylinder wall and the inserted reinforcing bar at an intermediate position between the tip and the base end in the axial direction, respectively, in the cylinder walls of the first and second connecting portions. Is formed,
Between the base end portion of the first connecting portion and the base end portion of the second connecting portion, the bridge portions that bridge the first and second connecting portions in a separated state are the first and first bridge portions. Two are provided at intervals in the circumferential direction of the connecting part,
The gap between the plurality of bridge portions exposes the tips of the one and the other reinforcing bars that have penetrated the first and second connecting portions, respectively.
A joint characterized in that the proximal end surface of the first connecting portion and the proximal end surface of the second connecting portion are visibly separated and opposed to each other. The joint according to claim 1, wherein the bridge portion is bridged so as to connect the outer peripheral surface of the first connecting portion and the outer peripheral surface of the second connecting portion. The joint according to claim 1 or 2, wherein the intermediate portion in the axial direction of the bridge portion is formed to be thicker than both ends. The joint according to any one of claims 1 to 3, wherein the plurality of bridge portions are provided at equal intervals. Female threads are formed on the inner peripheral surfaces of the first and second connecting portions to screw the threaded reinforcing bars, and the reinforcing bars inserted into the first and second connecting portions are threaded reinforcing bars. The joint according to any one of claims 1 to 4. At the base end and the tip of the first connecting portion, and at the base end and the tip of the second connecting portion, a sealing member made of an elastic material is radially within the inner peripheral surface of the cylinder wall. The joint according to any one of claims 1 to 5, wherein the joint is provided so as to project in a direction.

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