JP2810989B2 - Joining method of fiber reinforced plastic bar - 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 of joining a fiber reinforced plastic bar, and more particularly, to a method of joining a fiber reinforced plastic (FRP) bar used as a substitute for a reinforcing bar in a reinforced concrete building structure. The present invention relates to a method of joining ends.

[0002]

2. Description of the Related Art In order to join fiber-reinforced plastic bars conventionally used as main bars in a series direction, as in the case of joining deformed reinforcing bars, overlap joining is performed with the expectation of the adhesion of the bars themselves. Is adopted. Further, in order to increase the adhesive force of the ends of the bars to be joined, the bars are braided, or sand or the like is adhered to the surface of the ends of the bars with an adhesive.

[0003] Japanese Utility Model Laid-Open Publication No. 3-50119 discloses FRP.
There is shown a joint device in which a joint member having a male thread formed by die casting is integrally connected to an end portion of a bar material, and a joint member is coupled by a joint having a female thread.

[0004]

When an external force acts on a reinforced concrete structure, a tensile force or a compressive force mainly acts on the main reinforcement, but the performance required for a joint between the main reinforcements is mainly based on the maximum tensile strength possessed by the main reinforcements. The force is transmitted to the other main muscle. Therefore, according to the conventional joining method of the main bars, the maximum tensile force of the main bars is limited to the strength of the joining force (adhesive force) between the main bars at the joining portion of the main bar ends. Conversely, the strength of the adhesive force at the joint of the main bar determines the transmission of the tensile force of the main bar. Furthermore, since the adhesive force at the joint of the main bar is affected by the length of the joint and the strength of the frictional resistance of the surface of the end of the main bar, complicated operations such as lengthening the joint (joined portion) and attaching sand or the like are required. Work is required.

According to the joint device disclosed in the above-mentioned publication, the ends of the main bars are joined by a joint by a screw mechanism, and the adhesive force of the ends of the main bars does not act on the joining of the main bars. This has the advantage that it does not require any work such as lengthening the joints or strengthening the adhesion at the ends of the main bars, but on the other hand, the joint device must be attached to the ends of the main bars in advance, and However, there is a drawback that it cannot be used in a case where main bars of arbitrary length are joined in series. In addition, there is a concern that the joint strength between the end of the main bar and the joint device attached to the main bar is not problematic.

In view of the above, an object of the present invention is to clarify an improved joining method which can be freely attached to an end of a main reinforcing fiber made of fiber reinforced plastic to perform a strong in-line joining. Is what you do.

[0007]

According to the method of joining fiber reinforced plastic bars according to the present invention, a notch is formed at a fixed length at an end of a bar to be joined, and a wedge is formed at the cut portion. Insert and enlarge, and deform the end of the rod so that this enlarged part is absorbed by the tapered or concave part formed inside the female cone, and fix this state by integrating a pair of female cones with a coupler Or grouting material is applied or injected into the female cone.

[0008]

Next, a specific configuration of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3, reference numeral 1 denotes a bar (for example, a main bar) made of fiber reinforced plastic, 2 denotes a wedge, 3 denotes a female cone, 4 denotes a nut, and 5 denotes a coupler.

Prior to joining, a wedge 2 is attached to the end of the bar 1.
In accordance with the length, a notch is provided such as two or three or even four, and a wedge 2 is inserted into the center of the cut, and a female cone 3 is attached to the outside. Can be The workability is better if the female cone 3 is attached slightly deeper before the wedge 2 is inserted, and the female cone 3 is pulled out toward the end after the wedge 2 is inserted. At this time, as shown in FIG. 2, since the inside of the female cone 3 is formed in a tapered or concave step portion, the end of the bar 1 enlarged by the insertion of the wedge 2 is The female cone 3 is deformed along the inner taper, and when the coupler 5 is tightened in this state, the opposing female cones 3 are integrally joined, and both ends of the bar 1 are firmly joined. Become. Then, in order to prevent loosening of the coupler 5, both ends of the capsule <br/> Ra 5 is preferably to be fastened by a nut 4.

The present invention includes the following aspects.

When the wedge 2 is, for example, one in which the end of the bar 1 is divided into four, the cross-sectional shape of the wedge 2 becomes a cross shape or the like. An aspect having a cross-sectional shape corresponding to the shape.

An embodiment in which the wedge 2 has a circular cross section. An aspect in which the wedge 2 has a rectangular cross section. A mode in which the surface of the wedge 2 is rough to prevent slippage. A mode in which the wedge 2 is shaped like a wood screw. An aspect in which the wedge 2 is an integral type tapered in two directions, and is inserted into both ends of two rods 1 to be joined.

An embodiment in which the end surface of the bar 1 and / or the inside of the female cone 3 is formed to be rough or uneven.

A groove or the like is formed in the longitudinal direction of the inner tapered portion or the concave step portion of the female cone 3, the surface of the end portion of the bar 1 is locked, and idling is prevented when the coupler 5 is tightened. The embodiment configured as described above. Coupler 5
Various grout materials are applied to the periphery of the end of the bar 1 and the surface of the wedge 2 prior to tightening.

A mode in which a pair of pores are prepared in the front and back of the coupler 5 at substantially the center and a grout material is injected from one of the pores 6 . The completion of the injection is confirmed by discharging the grout material from the other fine holes 7 .

A mode in which a projection or a concave portion serving as a support point for rotation or holding by a tool when tightening with the coupler 5 and the nut 4 is formed on the surface of the coupler 5 or the end of the female cone 3.

Wedge 2, female cone 3, coupler 5 , nut 4
Wherein all or a part of is made of metal.

Wedge 2, female cone 3, coupler 5 , nut 4
Wherein all or a part of is made of synthetic resin.

An embodiment in which a notch is formed in advance at the end of the bar 1.

A mode in which it is necessary to make a cut in the end of the bar 1 during the joining operation. In the figure, 8 indicates a spiral.
You.

[0022]

According to the present invention, when joining fiber-reinforced plastic rods used as main reinforcing bars or the like in a concrete building in series, strong joining can be performed by a simple operation. The problem is solved.

[Brief description of the drawings]

FIG. 1 is a plan view of a joint to which the present invention is applied.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a sectional view taken along the line BB in FIG. 1;

[Explanation of symbols]

 1-rod material made of fiber reinforced plastic 2-wedge 3-female cone 4-nut 5-coupler 6-pore for grout injection 7-pore for grout discharge 8- spiral

Claims (2)

(57) [Claims] 1. A method of joining fiber-reinforced plastic bars in a series direction, wherein a cut is formed at a fixed length at an end of a rod to be joined, and a wedge is inserted into the cut portion to increase the size. The end of the rod is deformed to absorb the enlarged part into the tapered or concave part formed inside the female cone, and this state is fixed by integrating a pair of female cones with a coupler. The method of joining fiber reinforced plastic bars. 2. The method according to claim 1, wherein a grout material is applied or injected into the female cone.