JPH04353117A - Wire anchor body and anchoring method - Google Patents

Abstract

PURPOSE:To increase adhesion strength between a wire in a multiplex twisted wire and a concrete or grout through extremely simple structure and to reduce a necessary space. CONSTITUTION:The end part of a multiplex twisted wire 2 comprises a free length part 4 and a fixing part 6. The free length part 4 forms double structure protected by a pipe 8 but the fixing part 6 is in a state that wires 2B (and 2A), 2C, and 2D of the multiplex twisted wire 2 are left as they are. The fixing part is structured such that it is gradually shortened from the inside and end positions are displaced from each other. The end part thereof is inserted in an excavated hole 10 in a ground and grout 12 is pressed in. A concrete structure 14 is built at the opening part of the excavated hole 19. When a given strength is produced at the grout and concrete, a tension force is introduced to the multiplex twisted wire 2 and a head part is anchored by means of an anchoring body 16. A wire anchor is also effective to a wire of a new material except a steel material and has simple structure wherein an end is solely cut.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire anchor body made of multiple stranded wires used as tendons for concrete structures, ground anchors, and the like.

0002

[Prior Art] Fixed end structures using multi-stranded wire as tension members include structures with trimmed tips, structures with diffused tips, structures with expanded width in an onion shape, structures with bearing plates attached, bolts, etc. There are many structures with nuts attached. (For example, JP-A-1-163345, JP-A-1-163345, JP-A-1-163345,
See Publication No.-203517. ) However, a wire anchor body with fixed ends whose positions are shifted between the outer side and the inner side has not been realized.

0003

[Problem to be solved by the invention] In the above conventional technology,
When trying to fix the ends of multi-stranded wires in grout as tendons, there is a problem that it is difficult to fix the wires in the center, so the fixed end structure becomes large.
The problem was that it required a large amount of space. There was also the problem that the number of parts increased and the structure became complicated.

[0004] The object of the present invention is to have an extremely simple structure,
It is an object of the present invention to provide a wire anchor body and an anchor construction method that increase the adhesion strength between the central wire of a multi-stranded wire and concrete or grout and reduce the required space.

[0005]

[Means for Solving the Problems] The above object is to make outer wires shorter than inner wires among a plurality of twisted wires of multi-stranded wires, and to connect the ends of these wires by at least one stage. This can be achieved by a wire anchor body having a multi-stage end structure shifted as described above. Alternatively, when a multi-stranded wire is used as a tendon in a concrete structure or grout, the anchoring portion of the multi-stranded wire that is fixed to the concrete or grout is
This can also be achieved by making the outer wire rows of the plurality of twisted wires shorter than the inner wire rows, and creating a multi-stage end structure in which the ends of these wire rows are shifted by at least one step or more.

[0006] Furthermore, the above object is to create a multi-stranded wire in which the outer wires are shorter than the inner wires among a plurality of twisted wires of the multi-stranded wires, and the ends of these wires are shifted by at least one step. This can be achieved by fixing the wire anchor body of the end structure into the concrete structure or grout. Alternatively, of a plurality of twisted wires of the multi-stranded wire, the outer wire row is shorter than the inner wire row, and the ends of these wire rows are shifted by at least one step. This can also be achieved by fixing a wire anchor body in concrete or grout and then applying a tensile force to the multi-stranded wire to anchor the multi-stranded wire at a predetermined location.

[0007] Furthermore, the wire is not only made of steel, but also
Wires made of new materials, such as carbon fibres, aramid fibres, or glass fibres, can be used.

[0008]

[Operation] According to the above structure, the outer wire of the multi-stranded wire is made shorter than the inner wire, and the ends of the wire are shifted in multiple stages as necessary, so that the multi-stranded wire can be made into concrete or When it is fixed in grout, the adhesion area with concrete or grout increases from the outermost wire to the central wire, and the adhesion strength can be increased. Further, since the diameter of the end portion fixed with grout or the like is smaller than the outer diameter of the multi-strand wire, the diameter of a hole such as an excavation hole to which the multi-strand wire is fixed with grout or the like can be reduced.

[0009] Furthermore, since there is no need to create a complicated structure by simply cutting the tip of the wire, for example, carbon fiber,
Wires made of new materials such as aramid fibers or glass fibers can be effectively used.

0010

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a multi-stranded wire fixed end structure illustrating one embodiment of the present invention. In FIG. 1, the end of the multi-stranded wire 2 consists of a free length 4 and a fixed part 6. The free length part 4 has a double structure protected by a pipe 8, but the fixed part 6 is the same as the wires 2B (and 2A), 2C, and 2D of the multi-stranded wire 2, and the wires are connected sequentially from the inside wire. It has a structure in which it is shortened and the end portion values are shifted. This end is inserted into an excavated hole 10 in the ground, and grout 12 is press-fitted. A concrete structure 14 is constructed at the opening of the excavation hole 10, and when the grout and concrete have a predetermined strength, tensile force is introduced into the multi-stranded wire 2,
The head is fixed with a fixing body 16.

FIG. 2 is a cross-sectional view of the multi-stranded wire of this embodiment. In this embodiment, as shown in the figure, the multi-stranded wire 2 is centered around the innermost wire 2A (one wire).
Wires 2B (6 wires), 2C (12 wires), 2D (18 wires)
, a total of 37 wires are twisted four times. By sequentially shifting the ends of the wires 2A, 2B, 2C, and 2D, it is possible to adhere the grout to even the wires inside the multi-stranded wire 2, improving the adhesion strength of the multi-stranded wire 2. can be done.

Next, an example of a construction method using the wire anchor body of this embodiment will be explained step by step with reference to FIG. (1) A hole 10 with a diameter of 9 to 15 cm is drilled in the ground 18. (2) Next, it has a head fixing body 16, a fixed part 6, and a free length part 4, and the wire row on the outside side of the fixed part 6 is shorter than the wire row on the inside side to form a multi-stage structure (wires 2A and 2B, 2C, 2D
) is inserted into the hole. (3) Subsequently, grout 12 is injected into the excavated hole 10,
Apply pressure. (4) Next, construct the concrete structure 14. (5) Subsequently, when sufficient strength is generated in the grout and the structural concrete, a tension jack is set on the head anchor 16, and the multi-stranded wire 2 is pulled to introduce a predetermined tension. After introducing tension, head fixing body 1
6 is fixed and subjected to anti-rust treatment.

FIG. 3 shows another embodiment, and FIG.
In contrast to the example in which four stranded wires are arranged in three stages with the ends shifted, in this embodiment wires 2A, 2B, and 2C are grouped together, and this and wire 2D form two stages. Also in this embodiment, the fixing strength of the internal wires of the multi-stranded wire 2 can be improved compared to the case where the tips are cut to be aligned. Further, multiple stranded wires such as triple or quintuple wires can be grouped into several stages as appropriate.

According to a conventional general example, the rows of wires 2A, 2B, 2C of the multi-stranded wire 2 shown in FIG.
The structure is such that there is no contact with concrete or grout 6 other than the cut surface, and only the outer row of wires 2D contacts. Therefore, in the past, if you wanted to fix and fix the internal wires, you had to create a complicated structure.
According to the embodiment of the present invention, it is possible to maintain strength greater than that of the conventional example with a simple structure that does not use any fixing parts, and the diameter of the excavation hole can also be minimized. Furthermore, according to this embodiment, wires made of new materials such as carbon fiber, aramid fiber, or glass fiber, which are difficult to form into complex shapes or structures, can be easily and effectively processed by simply cutting the tip of the wire. It can be used for.

[0015]

As described above, according to the present invention, there is provided a wire anchor which has an extremely simple structure, increases the adhesion strength between the central wire of the multi-stranded wire and concrete or grout, and reduces the required space. and anchor construction methods.

[0016] Furthermore, excellent effects can be exhibited for multi-stranded wires made of new materials other than steel, such as carbon fiber, aramid fiber, or glass fiber.

[Brief explanation of the drawing]

FIG. 1 is a side view of a multi-stranded wire fixed end structure illustrating one embodiment of the present invention.

FIG. 2 is a cross-sectional view of the multi-stranded wire of this example.

FIG. 3 is a side view of a multi-stranded wire illustrating another embodiment of the invention.

[Explanation of symbols]

2 Multi-stranded wire 2A
One wire 2B in the center Six wires 2 surrounding one wire 2A in the center
C 12 wires 2D surrounding the row of wires 2B 18 wires 4 surrounding the row of wires 2C Free length portion
6 Fixed part 8
pipe
10 Drill hole 12 Grout
14 Concrete structure

Claims (6)

[Claims] 1. A multi-tiered end structure in which the outer wires of a plurality of twisted wires of the multi-stranded wire are made shorter than the inner wires, and the ends of these wires are shifted by at least one step or more. Wire anchor body with. 2. When a multi-stranded wire is used as a tendon in a concrete structure or grout, the fixed part of the multi-stranded wire that is fixed to the concrete or grout is the outer side of the plurality of twisted wires. A wire anchor body having a multi-stage end structure in which the wire rows are shorter than the inner wire rows and the ends of these wire rows are shifted by at least one step. 3. The wire anchor body according to claim 1, wherein the wire is made of a new material, such as carbon fiber, aramid fiber, or glass fiber. 4. A multi-tiered end structure in which the outer wires of a plurality of twisted wires of the multi-stranded wire are made shorter than the inner wires, and the ends of these wires are shifted by at least one step or more. An anchor construction method in which a wire anchor body is fixed into a concrete structure or grout. 5. A multi-tiered end portion in which an outer wire row of a plurality of twisted wires of the multi-stranded wire is made shorter than an inner wire row, and the ends of these wire rows are shifted by at least one step or more. An anchor construction method in which a structural wire anchor body is fixed in concrete or grout, and then tensile force is introduced into the multi-stranded wire to fix a predetermined portion of the multi-stranded wire. 6. The anchor construction method according to claim 4, wherein the wire is made of a new material such as carbon fiber, aramid fiber, or glass fiber.