JPH1037383A - Jointing structure for reinforcements and jointing method for reinforcements - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an easy jointing work for reinforcements at a construction site by lessening labor for rotating a connection bolt into a steel. SOLUTION: Jointing sleeves 3 and 4 are preliminarily fastened to each end of a pair of reinforcements 1 and 2 to be abutted and jointed to each other. A connection bolt 5 is passed through each of the sleeves 3 and 4, and both sleeves 3 and 4 are connected via the bolt 5. Regarding internal thread parts 3a and 4a formed on the sleeves 3 and 4, ridge cutout parts 4b are axially formed on the internal thread part 4a of the jointed sleeve 4 at opposed circumferential positions at every 90 degrees. Also, cutout parts 5b are axially formed over the prescribed length of a range from one end of the connection bolt 5 at opposed circumferential positions within a 90-degree range. When the cutout part 5b of the connection bolt 5 is kept faced to and made to near other than the cutout parts of the jointed sleeve 3 or 4, the connection bolt 5 comes to be inserted in the internal thread part 4a or 3a. As a result, thread ridges come to be engaged with each other via the 90-degree rotation of the reinforcement 2, and sleeves 3 and 4 are connected to each other, thereby jointing both reinforcements 1 and 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rebar connection structure and a rebar connection method in which deformed rebars are butt-connected to each other at a construction site such as civil engineering or construction.

[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 using a screw mechanism are employed.

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.
Is fixed. This is fixed to a construction site, and a connection bolt 63 having a male screw portion 63a engraved over the entire length of the female screw portion is screwed. Further, the sleeve 65 fixed to the end of the other deformed reinforcing bar 64 to be connected to the connection bolt is screwed to connect the sleeves to each other.

[0004] As a method of screwing the other sleeve 65 into the connection bolt 63, the connection bolt 63 is previously screwed into the sleeve 62 of one rebar to about half its length.
Next, the female thread 65a of the sleeve 65 of the other reinforcing bar 64 is aligned with the tip of the connection bolt 63, and the other reinforcing bar 64 is rotated to screw the thread into the female thread to connect the sleeves.

In the case where the above method cannot be adopted at a construction site, the female thread of one sleeve is lengthened, and a connection bolt in which two nuts are screwed is screwed deeply into the female thread. Next, a connection method is adopted in which the female thread portion 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]

The above-described mechanical joint of a reinforcing bar has advantages such as easy construction and low cost, and is expected to be further developed. However, since the screw mechanism is the main element in each case, the connecting rod must be turned many times or the connecting bolt must be turned many times during the connection work. There is a problem that the number of man-hours is increased. In particular, the rebar is heavy, and it takes time to rotate the rebar several tens of times every many rebars. Therefore, an object of the present invention is to reduce the trouble of rotating a connection bolt to an ironware.

[0007]

In order to achieve the above-mentioned object, the present invention provides a method for forming a female thread portion of one of the sleeves so that the outer peripheral surface of the female thread is formed in a range of not less than a quarter of the circumference. The connection bolt to be cut out and screwed into the cutout is also provided with a notch formed by cutting off the opposing surface of the circumference in a range of at least one-fourth of the circumference of the threaded portion. As described above, the notched portions of the threaded portion and the external threaded portion face each other, and the threads are engaged with each other, so that the connection bolt screwed to the sleeve fixed to the tip of one rebar and the tip of the other rebar Is connected to the sleeve, and the pair of rebars is eventually connected to each other.

In the connection method in the above-described connection structure of a reinforcing bar, a connection bolt is screwed into a female thread portion of one sleeve, and a female thread portion of the other sleeve is aligned with a tip of the connection bolt. And the other rebar is pressed towards one rebar,
A connecting bolt is inserted into the female thread. Here, 4 bars
By only making a one-half turn (turn by 90 °), the thread of the male thread and the thread of the female thread engage, the two sleeves are connected via the connection bolt, and eventually the rebars are connected. .

In another means, the connection bolt is inserted through the female thread portion of the other sleeve in the same manner as described above, and then the connection bolt is rotated by an angle of 90 degrees, whereby the screw of the connection bolt is screwed. The thread is engaged with the thread of the internal thread of the sleeve. This makes it possible to easily perform the butt connection of the rebars even under the condition that the rebar cannot be rotated.

[0010]

Next, a first embodiment of the present invention will be described. As shown in FIG. 1, a connecting sleeve 3 is attached to each tip of a pair of rebars 1 and 2 to be butt-connected.
The connection bolt 5 is screwed into the internal thread portions 3a and 4a of each sleeve. This connection bolt 5
, The sleeves 3 and 4 are connected to each other, and eventually the rebars fixing the both are connected to each other in a state where the reinforcing bars abut each other.

The sleeves 3 and 4 have screw portions 3a and 4a, respectively, as described above from one opening of the hole of the cylindrical body to a predetermined depth.
The rebars 1 and 2 are inserted and fixed in the middle of the hole on the opposite side that communicates with the female thread from the other opening. The rebars 1 and 2 and the sleeves 3 and 4 are fixed to each other in advance in a factory by cold crimping using a special swage crimping machine. While the internal thread 3a of one sleeve 3 has a thread formed on the entire circumference, the internal thread 4a of the other sleeve 4 has an angle range of 90 ° or more at each of the circumferentially opposed positions. A notch 4b is formed by cutting off a thread (see FIG. 1B).

On the other hand, the connecting bolt 5 is provided with a male thread 5a which can be screwed into the female thread of the sleeve over the entire length. Of the male screw portion 5a, a portion of approximately half the entire length to be screwed with the female screw portion 3a of one sleeve 3 is:
Although the thread is formed on the entire circumference, the remaining portion of the other sleeve which is to be screwed with the female thread portion 4a is cut at approximately 90 degrees in an angle range of approximately 90 degrees at opposing positions on the outer periphery. Notches 5b, 5b are formed. The cutouts 4b and 5b of the female thread and the male thread are provided so that the sleeve and the connection bolt can move relative to each other in the axial direction when connecting the reinforcing bars. When in the connected state as shown in FIG. 1, the thread portions 4c and 5c are engaged with each other, and the cutout portions 4b and 5b face each other to form a cavity. .

When the screw structure connected in this manner is employed, the strength in the axial direction is about half that of the prior art when the number of threads is the same, so that the number of threads to be screwed in the portion having the notch is almost doubled. It is desirable that Connection bolt 5
Since it is required to have a strength comparable to the mechanical strength of the reinforcing steel, it is desirable to use a special steel such as a Cr-Mo steel that has been subjected to a heat treatment of quenching and tempering.

Here, the connection procedure of the rebar according to the present invention will be described. First, one rebar 1 to which a sleeve 3 is fixed in advance at a tip in a factory is fixed at a predetermined position on a construction site. Next, the end of the connection bolt 5 having no notch is screwed into the female thread 3a of the sleeve 3. In some cases, the connection bolts may be attached in advance at a factory.

Next, the distal end of the portion of the sleeve 4 having the cutout 4b of the female thread 4a fixed to the distal end of the other reinforcing bar 2 faces the distal end of the sleeve 2 of one reinforcing bar 1.
Here, the cutout portion 5b of the connection bolt 5 and the remaining thread portion 4c of the female thread portion of the other sleeve are made to face each other (simultaneously, the remaining thread portion 5c of the male thread portion of the connection bolt and the female thread portion of the sleeve are formed). And the other reinforcing bar 2 is moved in the axial direction, and the connection bolt 5 is inserted into the internal thread 4 a of the sleeve 4.

When the rebar is rotated to the right or left by 90 degrees in the circumferential direction at the time when the ends of the sleeves 3 and 4 are inserted to the closest position, the remaining screw of each of the internal thread and the external thread is obtained. The mountains are engaged with each other to complete the connection structure as shown in FIG. If the ends of the threads collide with each other when rotating the other rebar and rotation becomes impossible, adjust the rebars slightly up and down so that the threads and the valleys of the threads match, then rotate It is good to let. In addition,
When the rotation angle is 90 degrees, the remaining threads of the internal thread and the external thread engage with each other under favorable conditions. Therefore, a mark is provided on the sleeve as a guide of the amount of rotation, or a stopper that regulates the amount of rotation. In order to improve the efficiency of the connection work and to secure the connection strength.

Next, a second embodiment of the present invention will be described. The connection structure of the reinforcing bars in this example is applied to a connection in a case where the reinforcing bars to be connected cannot be rotated because they are a bent material or an already fixed one.

As shown in FIG. 3, the connection structure of the reinforcing bar in this example is basically the same as that of the first example except that a fixing nut is employed. That is, the reinforcing bar 11,
Sleeves 13 and 14 fixed to 12 are the same as in the above-described example. The connection bolt 15 is also the same, but the total length of the bolt is increased by the amount of the nuts 16 and 17 interposed. The two nuts 16 and 17 screwed into the continuous bolt 15 employ standard JIS (Japanese Industrial Standard) standard products.

As shown in FIG. 4, the connection procedure in this embodiment is such that the notch 15b of the connection bolt 15 is not formed with the nuts 16 and 17 screwed into the female thread 13a of one sleeve 13. Screw. Next, the female thread portion 14a of the other sleeve 14 is inserted from the other end of the connection bolt 15, and the connection bolt is rotated by 90 degrees using a tool such as a torque wrench. This enables connection bolt 1
5 is unscrewed from the female screw hole of one sleeve 13 by a quarter pitch, and at the same time, the threads are engaged in the female screw portion 14a of the other sleeve 14 so that the sleeves are connected. You. Next, the nuts 16 and 17 are rotated so as to approach the sleeves 13 and 14, respectively, and are tightened with a predetermined torque so as to press the ends of the sleeves, thereby fixing the connection bolts 15 so as not to be loosened.

FIG. 5 shows a connection procedure at a construction site according to a second embodiment of the present invention, and shows a state in which main reinforcements of columns of a building are assembled. Each main bar (rebar)
11 and 12 are fixed by hoop streaks 18 and 19, and cage assembly K
1, K2.

The connecting procedure of the reinforcing bars in such a structure is as follows. First, the reinforcing bars of the lower cages K1 and K2 are fixed, and the connection bolts 15 are screwed into the sleeves 13 at each end.

Next, the upper car set K2 is dropped, the connection bolts 15 are respectively inserted into the sleeves 14,..., And the connection bolts 15 are rotated by 90 degrees and connected as described above. Next, the connection work is completed by fixing the connection bolts with the nuts 16 and 17 so as not to be loosened.

In each of the above-described embodiments, the cutout is provided only in one half of the one sleeve and the connection bolt, but may be provided in the entire length of both the freeve and the connection bolt. By adopting such a connection structure, it is possible to absorb even if a certain error occurs in the length of the rebar or the butt position, and it is possible for the worker to easily perform the connection work without requiring special skill training. Become.

[0024]

According to the present invention, since the connection is performed only by rotating the other reinforcing bar or the connecting bolt of the pair of reinforcing bars to be connected by 90 degrees, tens of reinforcing bars or connecting bolts are required in the prior art. Since the trouble of having to turn the wire is eliminated, the work efficiency at the rebar assembling site is improved. In addition, the connection bolts can adjust the interval between the reinforcing bars, so that errors in assembling the reinforcing bars can be absorbed, thereby facilitating the assembling work.

[Brief description of the drawings]

FIGS. 1A and 1B show a configuration of a first example of an embodiment of the present invention, in which FIG. 1A is a partially cutaway sectional view of the front, and FIG.
FIG. 4 is a sectional view taken along line AA of FIG.

FIG. 2 is an explanatory diagram showing a connection procedure.

FIG. 3 is a partially cutaway sectional view showing a connection structure of the second example.

FIG. 4 is an explanatory diagram showing a connection procedure.

FIG. 5 is an explanatory diagram showing a connection point of a reinforcing bar at a construction site.

FIG. 6 is a partially cutaway cross-sectional view showing a connection structure of a reinforcing bar according to a conventional technique.

[Explanation of symbols]

 1,2,11,12 Reinforcing bar 3,4,13,14 Sleeve 3a, 4a, 13a, 14a Female thread 4b, 13b, 14b Notch 5,15 Connection bolt 5a, 15a Male thread 5b, 15b Notch

Claims (3)

[Claims] 1. A reinforcing bar in which a connecting sleeve is fixed in advance to each end of a pair of reinforcing bars, and a connecting bolt is screwed into a female thread portion formed in the sleeve to butt and connect the reinforcing bars. In the joint structure of (1), a notch formed by cutting a screw thread is provided in the female thread portion of the sleeve and the external thread portion of the connection bolt so that the connection bolt can be inserted into the female thread portion of the sleeve. The thread of the female thread and the thread of the male thread inserted into the female thread engage with each other to connect the rebars via the two sleeves. Characteristic rebar connection structure. 2. The notch according to claim 1, wherein the notch is provided at least at a position opposite to the circumference of each of the female thread of the at least one sleeve and the external thread of the connection bolt.
A connecting structure for reinforcing bars, which is provided in a range of degrees of rotation. 3. A method of connecting rebars in which a connecting sleeve is fixed to each end of a pair of rebars in advance, and the sleeves are connected via connection bolts to butt and connect the rebars. At least a half of the total length of the internal thread portion of the sleeve and the connection bolt is provided with a cutout portion through which the connection bolt can be inserted into the internal thread portion of the sleeve, and the connection bolt is inserted into the internal thread portion of the sleeve. A method of connecting reinforcing bars, wherein the pair of reinforcing bars are butt-connected by inserting and rotating the one reinforcing bar or the connection bolt by a predetermined rotation angle.