JPH0626149A - Reinforcement joint metal fittings for reinforced concrete structure - Google Patents

Abstract

PURPOSE:To make it possible to manufacture joint metal fittings with ease, prevent reinforcing bars from being deviated, and generate resistant heat by the supply of electricity and facilitate demolishing work. CONSTITUTION:There are provided a pair of envelops which are interposed between each of cross-shaped reinforcements 3 and 5 where cross-shaped metal bodies 1 made of a punched metal plate are intersected while another pair of envelops 6 and 6' are installed, which envelop other reinforcing bars 5. The diameter of an arc formed with each leg of the metal fitting bodies 1 and each of the envelops 4, 4' and 6 and 6', is adapted to be virtually identical to the diameter T of nodes 8 of the reinforcements 3 and 5. Furthermore, a slit 7 is installed between each envelop. The width S of this slit is designed to provide such a span that the envelops 4, 4' and 6 and 6' may be fitted in a snapped state when the reinforcements 3 and 5 are pushed from the slits 7. The joint fittings press and hold the reinforcements so as to prevent them from being device horizontally and laterally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing bar joint fitting used for fixing reinforcing bars intersecting in a cross shape at the intersections.

[0002]

2. Description of the Related Art In a conventional ordinary reinforced concrete building, there is a method in which reinforcing bars intersecting with each other are tied together by a bundle of iron wires having a diameter of about 0.8 mm.
A method is known in which intersecting reinforcing bar portions are joined by electric welding. However, in this first method, the steel rods were only tied up, so the rebars could not be completely fixed, and when the tied up, the rebars were misaligned, or when the concrete was poured in, the rebars were misaligned, eventually resulting in a building. Had a drawback that its strength was significantly weakened, and that it caused cracking of concrete.

A second method for fixing rebars by electric welding
In the method of (1), since the reinforcing bar itself contains a considerable amount of steel material, the material of the welded part is changed by welding and the reinforcing bar becomes brittle, so that the strength of the building is considerably reduced.

Furthermore, in recent years, in the construction of concrete structures, consideration has been given to the time of dismantling the structure in advance. It is known that a high current is applied to the reinforcing bar of an existing reinforced concrete building to generate resistance heat in the reinforcing bar and cause destruction from inside the concrete, facilitating dismantling. However, the above-mentioned method of binding with the iron wire does not cause the intended breakage at the joint when a high current is applied. The reason is that the iron wire bundles melt before the joints are destroyed.

In order to improve such an ordinary conventional technique, the inventor of the present invention disclosed in Japanese Patent Application Laid-Open No. 63-603 related to the prior application of the present application.
In JP-A-51, a cylindrical metal fitting body having a plurality of notched slits having a width sufficient to accommodate intersecting rebars, and a partial arc shape left by providing the notched slits and each of the rebars We proposed a rebar joint fitting consisting of a leg retaining ring that clamps a leg extending from the outside in a direction that forms a right angle to the outside, and a rebar fixing screw that engages an internal screw provided inside the leg.

By the invention according to this proposal, the drawbacks of the two conventional methods described earlier, that is, the defects such as the displacement of the reinforcing bars and the decrease in the strength of the building, were avoided. In addition, it is convenient for internal destruction of concrete because it does not melt easily even when a high current is passed when it is necessary to dismantle the building. However, this reinforcing bar joint fitting is extremely preferable in function as a whole as compared with the conventional one, but has a drawback that its structure is complicated.

[0007]

According to the present invention, the structure is relatively simple, but it is easy and reliable to fix two reinforcing bars intersecting each other in a cross shape to each other. It is an object of the present invention to create a reinforcing bar joint metal fitting that can cope with the connection of reinforcing bars of various thicknesses such that internal destruction of concrete is sufficiently caused when a high current is applied to the reinforcing bars for dismantling.

[0008]

This object is achieved according to the invention by the measures specified in the subclaims.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described in detail with reference to the drawings. The first embodiment will be described with reference to FIGS. 1 and 2. As shown in FIG.
It is made by stamping a metal plate, for example, a hot iron plate having a relatively high electric resistance. At that time, the reinforcing bar joint metal fitting is a cross-shaped metal fitting body 1, and the surrounding portions 4, 4 and 4 ', 4'are left on both sides of each leg in the vertical direction in FIG.
Four notches 11 are formed from a thick metal plate in a cross shape so that the surrounding portions 6, 6 and 6 ', 6'remain on both sides of each leg in the lateral direction. The notch 11 does not necessarily have to be circular, and what is important is that the portion formed by each metal fitting body 1 and each pair of surrounding portions can easily be processed into a substantially circular arc shape around a round bar having a diameter T. All you have to do is This diameter T represents the size of the diameter of the section 8 of the reinforcing bar. Needless to say, the punching may be performed by punching from one iron plate so as to have a shape as shown in FIG.

As is apparent from FIG. 1, a slit 7 is formed between the surrounding portions 6 and 6'surrounding the reinforcing bar 5, and the interval is S. Although not visible in FIG. 1, a slit 7 similar to this is also formed on the reinforcing bar 3 in the vertical direction between the surrounding portions 4 and 4 '.
Is formed by. The space S between the slits 7 is the rebar 3
Alternatively, when the 5 is fitted through the slit 7 there, the width thereof expands to T, and when the 5 is fitted in the surrounding area, it is snap-engaged so as to return to the original position.

Each leg of the metal fitting body 1 and each surrounding portion 4; 4 ';
The diameter of the arc formed by 6; 6'is almost equal to the diameter T of the node 8 of the reinforcing bars 3 and 5, and when the reinforcing bars 3 and 5 are pushed through the slits 7, the reinforcing bars are displaced vertically or horizontally due to the surrounding portions. It is pressed and held so that it does not exist. Further, as can be seen from FIGS. 1 and 2, an air vent hole 9 having an appropriate size is provided at approximately the center of the surrounding area so that an air layer is not formed when the concrete is poured. The air vent hole 9 can be used to fix the reinforcing bar joint fitting more firmly to the reinforcing bar through the iron bundle wire in some cases.

In the case of the embodiment according to FIG. 1, the joint metal fittings that act so as not to shift with respect to the reinforcing bar are the frictional force due to the pressing of the surrounding section against the reinforcing bar or the end of the surrounding section located in the longitudinal direction of the reinforcing bar. It is the force that hits the knot 8 of the reinforcing bar. If this displacement prevention is not sufficient, it is possible to adopt the second embodiment as shown in FIG.

The essential difference between the first embodiment according to FIG. 1 and the second embodiment according to FIG. 3 is as follows. That is, the surrounding parts on both sides of each metal fitting body 1, for example, 6,
6; 6 ', 6'at the circumferential ends of the fin members 12, 1
2'is provided and the corresponding fin members 12, 1
Conveniently, when the 2'is pressed, the reinforcing bars are tightened so that the slit 7 formed in the first embodiment cannot be formed. The manufacturing method of this joint fitting is the same as that of the first embodiment and is basically similar to that of FIG. 2, and therefore its explanation is omitted here.

In the case of this second embodiment, in order to fix the reinforcing bar, first of all, the reinforcing bar is passed between the fin members 12, 12 'at the intersection of both reinforcing bars 3 and 5 and the reinforcing bar is placed in a stable position in the surrounding area. Then, spot welding 15 is performed while pressing the mutual fin members, and the spot members are fastened. This makes it possible to prevent the joint fitting from being displaced in the vertical or horizontal direction. In this case, the holes 9 provided to ensure the inflow of concrete serve as air vents.

There are various thicknesses of the reinforcing bar, and the thickness has been properly used according to the use, but recently, the number of concrete structures having a reinforcing bar thickness of about 50 mm has been increased. . In such a case, it is preferable to apply the third embodiment as shown in FIG. 4 as a reinforcing bar joint fitting particularly suitable. Its structure is essentially similar to the embodiment of FIG. At the circumferential ends of the respective surrounding parts 6, 6; 6 ', 6'followed by fin members 12, 12' similar to those of the embodiment of FIG. Not visible in the figure,
Similarly, there are enclosures 4, 4 and 4 ', 4'in the longitudinal direction, fin members 12, 12' are also provided, and the spacing between them is the slit 7.

A method of using this joint fitting will be briefly described below. First, the crossed rebars 3 and 5 are spread to bring a joint fitting to a predetermined position, and the rebar 3 is vertically housed in the surrounding area through the slit 7 between the fin members 12 and 12 'which are not visible in the figure. To do so. Next, a joint metal fitting is provided at a predetermined position of the surrounding portions 6 and 6'through the lateral reinforcing bars 5 through the slits 7 between the fin members 12 and 12 '. Then, the metal fitting is tightened by using the bolt 17 and the nut 18 at each fin member. Metal fitting body 1
The length of the arc formed by and the surrounding portion is the node 8 of the reinforcing bar 3 or 5.
Since it is shorter than the peripheral length by at least the slit length,
The joint fitting can be tightened sufficiently with the bolt 17 and the nut 18. Therefore, even if the concrete is poured at a very high speed, the joint fittings can be prevented from shifting.

Further, in order to prevent the joint metal fittings from being vertically displaced, as shown in FIG. 4, a cross-shaped metal fitting body 1 is used.
And / or at least two places in the surrounding part 6, 6'protruding towards the side facing the rebar, in this embodiment eight places, the rebar 3
With a spacing P corresponding to the height of the joint 8 and the pitch P of the joint, and spike-like projections 20 at the height of the joint 8 at most of the reinforcing bar.
Can be provided on the joint fitting. Therefore, even if the joint fitting is displaced, it is only for one pitch.

The protrusion 20 is fitted between the joint of the reinforcing bar and the joint 8 when the surrounding portion is tightened. If the protrusion 20 rides on the knot 8, it will move upward or downward to avoid the knot 8 because it forms a rounded cone. The shape, position and number of these projections 20 are not limited to FIG. It is possible to arbitrarily select such as providing four.

Of course, these projections 20 can be provided on the metal fitting body 1 or on all surrounding parts 4, 4 '; 6, 6' so that the joint metal fitting can be used in any orientation. Is. The protrusion 20 extending toward the reinforcing bar may be applied to the first and second embodiments.

As described above, in all of the above-mentioned three embodiments, the number of parts is small, and although the metal plate can be easily manufactured by punching and bending, the deviation of the reinforcing bar can be prevented. It has a remarkable effect. When the reinforced concrete structure is dismantled later, if the joint metal fittings are made of high-heat iron plates, sufficient resistance heat is generated, so that the concrete is easily destroyed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a reinforcing bar joint metal fitting of a first embodiment, which comprises a cross-shaped metal fitting main body and surrounding portions provided on both sides thereof.

FIG. 2 shows a developed view of a punched iron plate before bending in order to manufacture the joint fitting according to FIG.

FIG. 3 is a perspective view showing a reinforcing bar joint metal fitting having a fin member continuing from the circumferential end portion of the surrounding portion and showing a second embodiment for fastening by spot welding.

FIG. 4 is a perspective view showing a reinforcing bar joint fitting showing a third embodiment of the type in which bolts and nuts are used to tighten the joint fitting to the reinforcing bar.

[Explanation of symbols]

 1 metal fitting body 3 longitudinal rebar 4,4 'encircling part of the metal fitting body in the circumferential direction 5 lateral rebar 6,6' encircling part of the metal fitting body in the circumferential direction 7 slit 8 rebar section 9 air vent hole 11 Notch when punching a steel plate 12, 12 'Fin member following the surrounding part 15 Spot welding 17 Bolt 18 Nut 20 Protrusion protruding to the reinforcing bar side S Slit 7 interval T Reinforcing bar node 8 part diameter P Reinforcing bar node 8 pitch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akemi Yamaguchi 44-3 Sasahara, Kokubunji-cho, Shimotsuga-gun, Tochigi Prefecture 3 (72) Inventor Seiichi Mizukami 1396-2 Inuta, Iwase-cho, Nishi-Ibaraki-gun, Ibaraki Prefecture (72) Inventor Ueno Takao 1856 Yakushiji, Minamikawachi-cho, Kawachi-gun, Tochigi Prefecture (72) Inventor Seikatsu Uchida 2-2-32 Chuo, Soka City, Saitama Prefecture

Claims (5)

[Claims] 1. A reinforcing bar joint fitting used at a crossing portion for fixing reinforcing bars intersecting in a cross shape,
A cross-shaped metal fitting body (1) made by punching out a metal plate is inserted between the cross-shaped reinforcing bars (3, 5) intersecting each other. Reinforcing bar (3)
A pair of surrounding portions (4, 4 ') surrounding the same and the other reinforcing bar (5) extending in a direction perpendicular to the reinforcing bar (3) in a bending direction opposite to the surrounding part (4, 4'). And a pair of surrounding parts (6, 6 ') surrounding the metal fitting body (1) and each surrounding part (4, 4'; 6,).
The diameter of the arc formed by 6 ') is almost the same as the diameter (T) of the node (8) of the reinforcing bar (3, 5), and there is a slit between the surrounding parts (4; 4';6; 6 '). (7) is provided, and the width (S) of the slit (7) is such that when the reinforcing bars (3, 5) are pushed in from the slit (7), the surrounding portion (4; 4 ';6;6') is Reinforcing bar joint fittings, characterized in that they have a space such that they can fit in a snap shape, and the joint fittings are pressed and held against the reinforcing bars so as not to shift in the vertical or horizontal direction. 2. Each enclosure (4,4 ';6,6') comprises:
And / or to remove air when pouring concrete
Alternatively, the reinforcing bar joint fitting according to claim 1, wherein a hole (9) for passing an iron bundle wire for binding the fitting so as not to shift is provided. 3. A reinforcing bar joint fitting used for fixing a cross-shaped crossing reinforcing bar at the crossing point,
A cross-shaped metal fitting body (1) made by punching out a metal plate is inserted between the cross-shaped reinforcing bars (3, 5) intersecting each other. Reinforcing bar (3)
A pair of surrounding portions (4, 4 ') surrounding the same and the other reinforcing bar (5) extending in a direction perpendicular to the reinforcing bar (3) in a bending direction opposite to the surrounding part (4, 4'). And a pair of surrounding parts (6, 6 ') surrounding the metal fitting body (1) and each surrounding part (4, 4'; 6,).
The diameter of the arc formed by 6 ') is almost equal to the diameter (T) of the node (8) of the reinforcing bar (3, 5), and each surrounding portion (4;
4 ';6;6') are provided with one fin member (12, 12 ') following each of the adjoining joint ends, and each rebar (3, 5) is provided with a fin member (12, 12). 1
2 '), and after being housed in the surrounding area, the fin members (12, 12,
Reinforcing bar joint fittings characterized in that 12 ') are joined by spot welding (15). 4. A reinforcing bar joint fitting used at a crossing point for fixing reinforcing bars crossing in a cross shape,
A cross-shaped metal fitting body (1) made by punching out a metal plate is inserted between the cross-shaped reinforcing bars (3, 5) intersecting each other. Reinforcing bar (3)
A pair of surrounding portions (4, 4 ') surrounding the same and the other reinforcing bar (5) extending in a direction perpendicular to the reinforcing bar (3) in a bending direction opposite to the surrounding part (4, 4'). And a pair of surrounding portions (6, 6 ') surrounding the metal body (1) and each surrounding portion (4; 4';6;
The diameter of the arc formed by 6 ') is almost equal to the diameter (T) of the joint (8) of the reinforcing bar (3, 5), and the space between the surrounding portions (4;
4 ';6;6') so that the slits (7) remain, one fin member (12, 1) follows each end of each enclosure.
2 ') is provided so that the joint fittings do not shift vertically or horizontally after the respective reinforcing bars (3, 5) are passed through the fin members (12, 12') and housed in the surrounding area. Reinforcing bar joint fittings characterized in that the facing fin members (12, 12 ') are screwed. 5. A reinforcing bar (3 and / or 5) is provided in the longitudinal direction of the metal fitting body (1) or the surrounding portion (4, 4 '; 6, 6') in order to prevent the metal fitting from being displaced. Providing a plurality of protrusions (20) protruding toward the facing side and having a height of the rebar nodes (8) at most at intervals equal to or an integral multiple of the pitch (P) of the rebar nodes (8). The reinforcing bar joint fitting according to claim 1, wherein: