JP2912926B2 - Joining method between steel and concrete using welding dowel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining steel and concrete using a welding dowel, and more particularly to a method for joining an arc shield body (ferrule) to a steel material by stud welding without removing the arc shield body (ferrule). The present invention relates to a method for joining a steel material of a welding dowel capable of being buried in concrete as a strength material and concrete.

[0002]

2. Description of the Related Art Conventionally, a welding dowel has been used for joining steel and concrete. One example of this is when a concrete floor is formed on a steel beam in a building, a joining method using a metal welding dowel is adopted to increase the joint strength between the steel material of the beam and concrete. Have been. In this joining method, first, a number of dowels are fixed at predetermined intervals on the steel material of the beam by stud welding, concrete is poured from above, and the welded dowels are buried as a connector (joined body) in the concrete layer. To form. The structure of a generally used welding dowel comprises a metal dowel body formed in a rod shape and an arc shield. This dowel body is composed of a shaft made of steel bar, an enlarged head integrally formed at one end thereof, and a welded portion integrally formed at the other end. The tip is provided with a spherical flux that generates an inert gas when melted. This flux also functions as an electrode part at the time of stud welding.

[0003] The arc shield body is formed so as to cover the periphery of the welded part of the dowel body, prevents the molten metal from diffusing to the periphery during stud welding, and seals the welded part with an inert gas generated from the flux. It is provided to maintain the performance and prevent oxygen from being supplied to the welded portion from the outside. The arc shield body is made of a material that can withstand high temperatures during welding, for example, a ceramic material such as ceramic. In order to form a joint between steel and concrete by using such a welding dowel structure, first, a large number of dowel bodies covered around the welded portion with an arc shield body are stud-welded at predetermined intervals on the steel material. Stick.
Next, after each arc shield body is broken and removed with a hammer or the like, concrete is cast on a steel material to form a concrete layer in which a welding dowel is embedded as a joint (connector).

[0004]

However, such a conventional method of joining steel and concrete using a welded dowel structure uses a conventional arc dowel structure attached to a large number of welded dowel structures. It took a lot of trouble and cost to remove it. Further, it has been difficult to mount the arc shield body in close contact with a predetermined position of the dowel body. In addition, the buried dowel body may be subject to strong lateral stress, but as a countermeasure, it is usually necessary to make the cross-sectional area of the welded part large enough to withstand the stress. Contributed to the increase in costs. Accordingly, an object of the present invention is to provide a method for joining steel and concrete using a welding dowel which has solved the conventional problems.

[0005]

That is, the method of joining steel and concrete using the welding dowel of the present invention is a rod-like joining method .
The dowel body 2 and the outer periphery of the tip of the body 2 are fitted.
With the tip surface slightly receding from that of the body.
In a position where it cannot be moved relative to its body.
A pedestal 4, the tip and the tip outer of the body 2 of the pedestal 4
Between the circumference and the outer circumference of the arc shield body 3
And arc shield holding portion 3a which is recessed in an annular, its A
Arc shield body fitted to the arc shield holding part 3a
3, the tip of the dowel body 2 and the steel material 12
Arc discharge between the surface and the tip
Surface, and then the dowel body 2 is
To move the bottom surface 11 of the base 4 to the steel material 1.
2 and the surface is positioned by the contact
At the set position, the molten portion of the surface of the steel material 12 and the dowel body 2
Welding the melted part to each other, and the arc seal
The dowel body 3 and the pedestal 4, and the
Concrete 17 on the steel 12 so that
To form a joint between steel and concrete
And, those having a. Further preferred practice of the invention
In the embodiment, the pedestal 4 is caulked or halved.
The main body of the dowel with the wedge 14 and the snap ring 16
2

[0006] In another more preferred embodiment of the present invention, the one in which the arc shield body is formed of a ceramic material in which the reinforcing bar 4a is embedded is used.

[0007]

Bonding between the steel and concrete utilizing welding dowels of the operation and effect of the present invention, the arc shield is, it
What it is held in the arc shield holding portion 3a matching
Thus, the arc seal body can be attached to a predetermined position of the dowel body in close contact with exactly. Then, the pedestal is fixed to the dowel body, and after the arc discharge, the dovetail body is turned to the steel material side.
When moved, the bottom of the pedestal contacts the surface of the steel material,
Steel surface and dowel at position fixed by contact
Since the body tip is welded to each other, the reliability of welding is assured.
And the bottom surface of the pedestal and the steel surface
The state of reliable contact can be automatically formed. And that
When lateral stress is applied to the dowel body by the contact , the pedestal surely acts as a support of the dowel body. Therefore, it is possible to sufficiently withstand a strong lateral stress without increasing the sectional area of the welded portion of the siber main body.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 1 is a sectional view showing an example of a welding dowel structure according to the joining method of the present invention. The welding dowel structure 1 according to this joining method includes a rod-shaped dowel body 2 and a high-strength arc shield body 3 fitted on the outer periphery of the tip. The dowel body 2 is made of a metal material such as a steel bar, for example, and is integrally provided with the shaft portion 5 and a head portion 18 having an enlarged cross-sectional area. A weld is formed at the lower end of the shaft 5 and a spherical flux 7 not shown in FIG.
(See FIG. 3). This flux is made of a material composition commonly used in this field, and emits an inert gas upon melting and acts as an electrode to steel during stud welding.

The arc shield body 3 is formed by integrally forming a lower cylinder body 8 and an upper cylinder body 9 having a smaller sectional area than the lower cylinder body 8 by, for example, a mold or the like. For this purpose, a large number of uneven portions 10 are formed. The arc shield body 3 can be made of a ceramic material such as ceramic commonly used in this field, for example, with a strength higher than that of concrete. In order to perform stud welding as shown in FIG. 1, first, an arc shield 3 is fitted to the tip of the stud body 2. Next, the steel material 12 and the stud body 2 are connected to the output side of a welding power source (not shown), and the flux of the stud body 2 is brought into contact with the surface to be welded.
By supplying a welding current, the stud main body 2 is slightly separated from the steel material 12 after energization, and electric discharge is started to melt the tip of the stud main body 2 and a part of the steel material surface. When the welding is started, the diffusion of the molten metal from the welded portion is prevented by the arc shield body 3, and the inert gas generated from the flux 7 is filled around the welded portion, thereby preventing the inflow of oxygen from the surroundings. Is done. After the elapse of the set time, the supply of the welding current is stopped, and the stud body 2 is pressed against the steel material, so that the molten portions of both are cooled to form the welded portion 13. Then, the molten metal enters the gap between the arc shield body 3 and the stud main body 2 and solidifies, and the space between them and the steel material is integrated.

FIG. 2 is a sectional view showing another example of the arc shield used in the joining method of the present invention. This arc shield body 3 is an example shown in FIG. 1 only in that a reinforcing bar 4a, for example, a spirally wound steel wire is embedded in a lower tubular body 8 and an upper tubular body 9 integrally made of ceramic material. And different. By reinforcing the arc shield body 3 with the reinforcing bars 4a in this manner, the material strength of the arc shield body 3 is increased, and the welded portion of the stud body 2 is reinforced. FIG. 3 shows a stud structure according to another embodiment of the joining method of the present invention. A welding dowel structure 1 formed by this joining method comprises a rod-shaped dowel body 2, a pedestal 4 firmly fixed to its tip end to prevent its movement in the axial direction, and an arc shield holding portion 3a recessed on the lower surface of the pedestal. And a high-strength arc shield body 3 fitted to the holding portion 3a. The pedestal 4 can be made by cutting or plastically processing a highly rigid metal material such as steel. In the illustrated example, the arc shield holding portion 3 has an inner wall of a pedestal 4 formed in a cylindrical shape and conforms to the outer shape of the arc shield body 3.
It has a step shape as a. The fixing position of the pedestal 4 with respect to the dowel body 2 is such that the tip of the dovetail body 2 is melted,
When the dowel body 2 is stud welded to steel, the bottom surface 11 of the pedestal 4 is located at a position in contact with the surface of the steel.

FIG. 4 is a partial sectional view showing a state in which the welding dowel structure of FIG. To perform stud welding in this way, first, as shown in FIG. 3, the arc shield holding portion 3a of the stud body 2 to which the pedestal 4 is connected.
The arc shield body 3 is fitted in. Next, stud welding may be performed in the same manner as in the above embodiment.

FIG. 5 is a partial cross-sectional view showing a state in which another example of the welding dowel structure of the present invention is used to stud-weld the steel 12. In this example, the pedestal 4 on the dowel body 2
3 is different from the example of FIG. The upper inner peripheral surface of the pedestal 4 is tapered, and a half wedge 14 is fitted between the tapered surface and the outer peripheral surface of the dowel body 2. FIG. 6 is a perspective view of the half wedge 14.

FIG. 7 is a partial cross-sectional view showing a state where another example of the welding dowel structure of the present invention is used and stud welding is performed on a steel material 12. This example differs from the example of FIG. 3 only in that the connection of the pedestal 4 to the dowel body 2 is made by a circumferential groove 15 provided in the dowel body 2 and a snap ring 16 fitted into the groove. The retaining ring body 16 has a shape in which a part of the ring body is cut out, and the circumferential action of the circumferential groove 15
Can be fitted into The snap ring 16 can be made of, for example, a steel material or a plastic material. FIG. 8 is a perspective view of the snap ring body 16.

[Brief description of the drawings]

FIG. 1 is a sectional view of a welding dowel structure according to a joining method of the present invention.

FIG. 2 is a longitudinal sectional view of another embodiment of the arc shield used in the joining method of the present invention.

FIG. 3 is an exploded partial sectional view showing an example of a welding dowel structure used in another joining method of the present invention.

FIG. 4 is a partial cross-sectional view showing a state where the welding dowel structure shown in FIG.

FIG. 5 is a partial sectional view showing a state in which another example of the welding dowel structure according to the joining method of the present invention is stud-welded to a steel material 12.

FIG. 6 is a perspective view of a half wedge shown in FIG. 5;

FIG. 7 is a partial cross-sectional view showing a state in which a welding dowel structure according to still another joining method of the present invention is stud-welded to a steel material 12.

FIG. 8 is a perspective view of the snap ring body 16 shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Welding dowel structure 2 Dowel body 3 Arc shield body 3a Arc shield holding part 4 Pedestal 4a Reinforcing bar 5 Shaft part 6 Welding part 7 Flux 8 Lower cylinder 9 Upper cylinder 10 Uneven part 11 Bottom 12 Steel 13 Welding part 14 Half Wedge 15 circumferential groove 16 snap ring 17 concrete 18 head

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-276778 (JP, A) JP-A-61-206002 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) E04B 1/48 B23K 9/20

Claims (5)

(57) [Claims] And 1. A rod-shaped dowel body 2, while being fitted to the distal end outer periphery of the main body 2, than that of the distal end surface is the body, at a position slightly retracted, so that it can not move relative to the body a between the pedestal 4 fixed, and the main body 2 tip outer periphery and distal end of the pedestal 4 in
Annularly depressed to match the outer circumference of the shield 3
And arc shield holding portion 3a which, Akushi which is fitted to the arc shield holding portion 3a
And a body 3 between the tip of the dowel body 2 and the surface of the steel material 12.
To discharge the tip and the surface of the steel material, and then move the dowel body 2 to the steel material 12 side.
Thus, the bottom surface 11 of the pedestal 4 is brought into contact with the surface of the steel material 12.
At the position determined by the contact.
The fusion zone of the surface of the material 12 and the fusion zone of the dowel body 2
The arc shield body 3 and the pedestal 4
As the reel body 2 is embedded, bonding method of the steel and concrete with welded dowel having the steps of causing forming a joint between the steel and concrete by Da設concrete 17 on the steel 12. 2. A bonding method of the steel and concrete of claim 1, the pedestal 4 is coupled to the dowel body 2 by caulking. 3. A method of bonding between the steel and the concrete claim 1, which is connected to the dowel body 2 by the pedestal 4 is half wedge 14. 4. The method for joining steel and concrete according to claim 1 , wherein the pedestal 4 is connected to the dowel body 2 by a snap ring 16 which is engaged with a circumferential groove 15 provided in the dowel body 2. 5. The method of joining steel and concrete according to claim 1, wherein the arc shield body 3 is made of a ceramic material having reinforcing bars 4a embedded therein.