JP2001146742A - Anchor tendon construction for double rustproof type permanent anchor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an anchor lighter and reduce the cost without impairing double rustproof functions. SOLUTION: From the tip portion of an uncovered portion L1 at the tip side of a partially unbonded PC stranded steel wire 12 to the tip portion of a covered portion L3 is covered with a rustproof pipe 14, and the tip portion of this rustproof pipe is sealed under a water stop treatment. And each terminal of fabrics-made packer 22 distributed from the peripheral surface of the rear end portion of the rustproof pipe 14 to the peripheral surface of the covered portion L3 of the partially unbonded PC stranded steel wire 12 is coupled and fixed by accompanying the water stop treatment to respective overlapped portion, and a capsule-shaped rustproof body 23 separated between the inside and outside of the waterproof pipe is formed to the uncovered portion L1 at the tip end side of the partially unbonded PC steel stranded wire.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a partially unbonded
The present invention relates to an uncurtain-don structure of a double rust-proof permanent anchor for covering double rust by covering a PC steel stranded wire with a rust-proof tube such as a corrugated sheath.

[0002]

2. Description of the Related Art As an uncurtain don of a permanent anchor for fixing the ground, various structures, etc. (ground, etc.), for example, a partially unbonded PC steel wire in which a PC steel wire itself is partially covered with an unbonded tube is tensioned. Material
A so-called double rust preventive type is known, in which the partially unbonded PC steel strand is covered with a rust prevention tube such as a corrugated sheath so that the rust prevention of the PC steel strand itself is double or more.

Generally, in this type of double rust-proof permanent anchor uncurtainer, the entire length of the partially unbonded PC steel strand is covered with a rust-proof tube such as a corrugated sheath. It is sealed under water stop treatment, and rustproof and sealed between the rear end of the rust prevention tube and the head fixing part under the jacket with a joint rust prevention tube such as an accordion connector. The inside and outside of the rust prevention tube are isolated. Then, after the insertion into the anchor hole of the target ground or the like, under the grout to the inside and outside of the cladding tube, the uncoated portion on the tip side not covered by the unbonded tube is fixed by the fixing length portion, and by the unbonded tube. The creation and construction of a permanent anchor having a covering portion as a free-length portion can be made by using this curtain rod.

[0004]

Generally, permanent anchors are constructed and constructed on the premise of permanent use. Therefore, in the conventional construction, durability against rust, corrosion, and the like is not assured for permanent use. Unbonded with a rust-proof tube such as a corrugated sheath for the purpose of obtaining as high as possible
The double coating of the PC steel strand on the PC steel strand itself, that is, the so-called double rust prevention, is generally performed.

[0005] However, the known uncurtain don having a structure in which the entire length of the partially unbonded PC stranded wire is covered by a rust-preventive pipe such as a corrugated sheath is heavy, and the weight of the uncurtain don is increased during the transfer work and the placement work. It cannot be denied that the workability in the above is adversely affected. It is also considered that the cost increase due to the necessity of a long rust prevention tube such as a corrugated sheath is one of the problems in the uncurtain don of the double rust prevention type permanent anchor.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a double rustproof permanent anchor having an uncurtained structure which can reduce the weight and the cost without impairing the double rustproof function.

[0007]

In order to achieve this object, according to the present invention, from the tip of the uncoated portion on the tip side defined on the tip side of the partially unbonded PC steel strand to the tip of the coating portion. Is covered with a rust-proof tube of a corresponding length, the tip of the rust-proof tube is sealed under a predetermined water stop treatment, and a partial unbonded PC is attached from the peripheral surface of the rear end of the rust-proof tube. By connecting and fixing each end of the cloth packer placed on the surrounding surface of the covered part of the steel stranded wire with water stoppage treatment to each overlapping part, this partial unbonded PC steel wire tip side uncoated A rust preventive body in the form of a capsule isolated between the inside and the outside of the rust preventive tube is formed in the portion.

[0008] In addition to this, the supporting plate disposed at the head fixing portion is formed in a form having a number of insertion holes corresponding to the number of partially unbonded PC steel strands. A joint rust-prevention pipe placed over the uncoated portion and the coated portion on the rear end side defined on the rear end side of the wire is disposed around the water-stopping treatment, and the insertion hole of the support plate is provided. It is preferable to insert a partially unbonded PC stranded wire every time.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[0010] As shown in Fig. 1, in the uncurtain-don structure of the double rust-proof permanent anchor according to the present invention,
The uncurtain don 10 has a predetermined length on the front end side (lower right side in the figure) and a predetermined length on the rear end side (upper left side in the figure).
The uncovered portions L1 and L2 are formed by themselves, and a predetermined length between the uncovered portions (from the lower left side to the upper right side in the figure) formed by coating with the unbonded tube 12b accompanied by rust-preventive oil is used as the coating portion. L3, so-called partially unbonded PC steel strand 12, is formed as a tension member. By covering the partially unbonded PC steel wire 12 with a rust prevention tube 14 such as a corrugated sheath, double rust prevention of the partially unbonded PC steel wire in the uncurtain don 10 is achieved.

The uncurtain don 10 is inserted into an anchor hole 18 of the ground, various structures (ground, etc.) 16 to be fixed, reinforced and the like. Then, grout is applied to the inside and the outside of the rust-preventive pipe 14, and the unbonded PC stranded wire (tensile material) 12 is tensioned and fixed by a predetermined load, whereby the double rust-proof permanent anchor 19 is constructed.

[0012] Such a partially unbonded PC steel strand 12
In the case of the uncurtain don 10 having the tension member
The tip-side non-coated portion L1 consisting of itself is used as a fixing length portion to be solidified by grout, and the unbonded tube 12b
The covering portion L3 covered by the above is defined as a free length portion (also referred to as a non-fixing length portion) that expands and contracts during tension and fixing.

The uncoated portion L2 on the rear end side of the partially unbonded PC steel strand 12 is defined as a head anchoring section. In the head anchoring section, the partially unbonded PC strand is tensioned.
Be established.

Since the uncurtain dong itself using a partially unbonded PC steel strand as a tensioning material is known, and the basic structure of the entire uncurtain dong is almost applicable, the embodiment of the present invention will be described. In
A detailed description of mutatis mutandis portions of the known basic configuration will be omitted in some cases.

Here, in the present invention, the coating portion L3 of the partially unbonded PC steel strand is formed by the unbonded tube 12b.
It is noted that double rust prevention due to the rust prevention oil filled therein is regarded as a separated portion. Therefore, as can be seen from FIG. 1, according to the present invention,
A portion from the front end of the uncoated portion (fixed length portion) L1 of the partially unbonded PC steel strand to the front end of the coating portion L2 is covered with a rust prevention tube 14 of a corresponding length, for example, a corrugated sheath or the like. That is, in the present invention, the rust prevention tube (corrugated sheath) 14 is formed not to have a length corresponding to the entire length of the uncurtain don as in the known configuration, but to have a length corresponding to only the front-end-side uncovered portion L1. ing.

The rust prevention tube 14 is not the same length as the front-side uncovered portion L1, but is, for example, slightly longer from the front-side non-covered portion to the front and rear ends thereof. It is preferable to form a rust prevention tube.

The tip of the rust prevention tube 14 is sealed, for example, under a water stopping process using a water stopping material 20.
Each end of the cloth packer 22 placed on the peripheral surface of the unbonded tube 12b of the covering part L3 from the rear end peripheral surface of the rust prevention tube to each overlapping portion, that is, water stopping treatment on the rust prevention tube and the unbonded tube. By connecting and fixing each together, the isolated capsule-shaped rust preventive body 23 inside and outside the cladding tube is formed in the tip side non-covering portion L1.

As can be seen from FIG. 2 in addition to FIG.
The cloth packer 22 is formed, for example, in a substantially cylindrical
One end of the intubation tube 24 is inserted and fixed in advance to the terminal located on the 14 side, that is, to the distal end portion. Then, the other end of the insertion tube 24 is inserted into the rear end of the rust-preventive tube 14, and the peripheral surface of the rear end of the rust-preventive tube and the peripheral surface of the front end of the cloth packer 22 are continuously taped. Thus, the rust prevention pipe and the cloth packer are connected and fixed together with the water stopping process.

As shown in FIG. 1, the end of the cloth packer 22 located on the unbonded tube 12b side of the covering portion L3, that is, the rear end portion is accompanied by a water stopping process by a water stopping material 26 therein. For example, it is fixed and sealed with respect to the unbond tube under the surrounding fastening by the wire 27 or the like.

An inner grout hose 28 and an outer grout hose 30 are inserted into the inside of the rust preventive tube 14 in the same manner as in the known basic configuration, and cover the end of the outer grout hose penetrating the rust preventive tube. As described above, the end cap 32 having the flow hole 32a is connected and fixed to the tip of the rust prevention tube.

As shown in FIG. 1, the anchor rod 10 having such a structure is inserted into the anchor hole 18 in the ground or the like from the tip, that is, from the end cap 32 side, as described above. Then, the inner grout, that is, the injection and filling of the grout material 34 into the rust prevention pipe 14, and the outer grout, that is, the injection and filling of the grout material 36 into the anchor hole are performed by the inner grout hose 28 and the outer grout hose. 30 is performed through each of the unbonded PC steel strands at the rear end side uncoated portion L2 after solidification of each grout.
The double rust-proof permanent anchor 19 is constructed under the tension of 12 and the fixing by the fixing device 42 including the combination of the anchor head 38 and the wedge 40 and the like.

As described above, in the uncurtain-don structure of the double rust-proof permanent anchor according to the present invention, only the uncoated portion L1 on the tip side of the partially unbonded PC steel strand 12 is covered with the capsule-shaped rust preventive body 23. By doing so, double rust prevention is achieved at the tip side non-coated portion, that is, at the fixing length portion.

In general, there is a relationship of the fixing length portion <the free length portion in the uncurtain don, and the length ratio of the fixing length portion is, for example, about 1/4 to 1/6 of the entire length of the uncurtain don. . In other words, according to the present invention, in which the length of the rust-preventive tube 14 is set to a length corresponding to the tip-side uncovered portion L1, the length of use of the rust-preventive tube per uncurtain-don covers almost the entire length. Since it is greatly reduced as compared with the conventional uncurtain-don, it is possible to surely reduce the cost and the weight associated with the reduction in the use length of the rust prevention tube.

Since the uncovered portion L1 of the tip end of the partially unbonded PC steel strand 12 is covered with the rust preventive body 23 in the form of a capsule, the double rust prevention function of the uncurtain-don is not impaired at all. Therefore, it is possible to easily secure the weight and cost of the uncurtain-don without impairing the double rust prevention function.

Further, in the uncurtain-don structure of the present invention, the front end of the rust preventive tube 14 is sealed under the water stopping process by the water stopping material 26, whereas the rear end of the rust preventive tube 14 is closed. It is sealed under the provision of the fabric packer 22 with a water stopping process.

Such a cloth packer 22 has air permeability. In other words, even with the rust preventive body 23 formed in a capsule shape by sealing each end of the rust preventive pipe 14, the air inside the rust preventive body, that is, the air inside the rust preventive pipe, passes through the cloth packer to the outside. Because of the escape, the exhaust inside the rust-preventing pipe can be surely performed at the time of internal grouting without providing an exhaust pipe or the like in the rust-preventing body. Therefore, such a rust preventive 23
Even with the configuration of the present invention for preventing rust of the non-coated portion L1 on the tip side, the internal grout for the rust prevention tube 14 does not involve complicated operation and complicated configuration.

By the way, in the uncurtain don 10, rust prevention at the boundary between the uncoated portion (head fixing portion) L2 and the coated portion (free length portion) L3 on the rear end side of the partially unbonded PC stranded wire 12 is achieved. That is, rust prevention in the head fixing portion is required.

Here, as can be seen from FIG. 3 in addition to FIG. 1, in the present invention, the head fixing portion of the uncurtain don 10 defined on the rear end side of the partially unbonded PC steel strand 12 is provided. Supporting plate 44 disposed on the rear end side uncovered portion L2
Are formed in a form having a number of insertion holes 46 corresponding to the number of partially unbonded PC stranded wires 12. As can be seen from FIG. 4 (A) in addition to FIG. 1 and FIG. 3, a joint preventive member arranged over the uncoated portion L2 and the coated portion L3 on the rear end side of the partially unbonded PC steel strand 12 is shown. A rust pipe 48 is arranged around the water stopping material 50 with the water stopping material, and the insertion hole 46
Each partial unbonded PC steel wire is inserted.

As shown in FIGS. 3 and 4 (A), this joint rust prevention tube 48 has an outer flange at the end on the side of the head fixing portion.
It is formed into a substantially T-shaped side surface having 48a, inside which a water-stopping material 50 is filled around the unbonded PC steel strand.

In this configuration, each of the partially unbonded PC steel strands 12 is individually covered and water-stopped by the joint rust preventive tube 48, so that the rust prevention at the head fixing portion L2 of the uncurtain don 10 is performed. Can be appropriately and easily performed without complicating the configuration.

Here, in the present invention, it is sufficient that the partially unbonded PC steel strands 12 are individually inserted into the corresponding insertion holes 46 of the support plate 44. Since this work is easier than the work of the known configuration in which a plurality of partially unbonded PC steel strands are collectively inserted into the large-diameter insertion hole provided in the support plate, the workability is ensured. To be improved.

Since the joint rust preventive tube 48 has a shape having an outer flange 48a, a concave step 46a for accommodating the outer flange 48a is formed at the opening end of the insertion hole 46 of the supporting plate. Provided. 3 and 4
As shown in (A), in the present invention, the concave step 46a of the insertion hole is formed in a shape shallower than the thickness of the outer flange 48a of the joint rust prevention tube.

As shown in FIG. 4B, according to this configuration, the anchor head 38 is fixed when the anchor rod 10 is fixed.
The outer flange 48a is squeezed and deformed under a load applied from the outside, so that the sealing on the outer flange side is ensured under close contact due to the squeezed deformation. Thereby, the water stopping and rust prevention inside the joint rust prevention tube 48 are further improved.

The embodiments described above are for explaining the present invention, and do not limit the present invention in any way. All the modifications and alterations within the technical scope of the present invention are not limited thereto. It goes without saying that it is included in the invention.

[0035]

As described above, according to the uncurtained structure of the double rust-preventive permanent anchor according to the present invention, only the uncoated portion on the tip side of the partially unbonded PC steel strand is covered with the capsule-shaped rust preventive body. Since coating is sufficient, the length of use of the rust preventive tube per one uncurtain-don can be greatly reduced.
Accordingly, the weight and cost of the uncurtain don can be easily and reliably reduced without impairing the double rust prevention function of the uncurtain don.

Further, since the rear end of the rust preventive tube is sealed with a breathable cloth packer, the exhaust inside the rust preventive tube during internal grout can be reliably performed through the cloth packer. Therefore, complication of the work at the time of internal grouting and complication of the configuration are reliably prevented.

Since the partially unbonded PC stranded wires are individually inserted into the insertion holes of the supporting plate via the joint rust proof tube, each of the partially unbonded PC stranded wires is connected to the joint rust proof tube. Is individually coated and water-stopped. Accordingly, rust prevention at the head fixing portion of the uncurtain don can be appropriately and easily performed without complicating the configuration.

Furthermore, since it is sufficient to insert the partially unbonded PC steel strands individually into the corresponding insertion holes of the support plate, the work of inserting the partially unbonded PC strands into the insertion holes is facilitated. Workability is definitely improved.

If the concave step of the insertion hole of the support plate is formed to have a shape smaller than the thickness of the outer flange of the joint rust preventive tube, it can be subjected to a load applied from the anchor head when the anchor rod is fixed. Since the outer flange is squeezed and deformed, sealing on the outer flange side is ensured under close contact due to the squeezed deformation. Water stoppage and rust prevention inside are further improved.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view, partially broken away, of an uncurtainment structure of a double rustproof permanent anchor according to the present invention.

FIG. 2 is a schematic exploded perspective view between a cloth packer and a rust preventive tube in an uncurtain-don structure of a double rust-proof permanent anchor.

FIG. 3 is a schematic perspective view of a partial disassembly of a supporting plate and a joint rust prevention tube in an uncurtain-don structure of a double rust-proof permanent anchor.

FIG. 4 is a partial cross-sectional view of an uncurtainment structure of a double rust-proof permanent anchor before and after a load is applied from an anchor head.

[Explanation of symbols]

 10 Uncurtain-don (of double rust-proof permanent anchor) 12 Partially unbonded PC steel wire 14 Rust-proof tube 22 Cloth packer 23 Rust-proof body 44 Pressure plate 46 Insertion hole 48 Joint rust-proof tube

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Masayoshi Fukai 5-8-13-1701 Minamisuna, Koto-ku, Tokyo (72) Inventor Kazuhiko Nishikawa 1-5-8 Yaesu, Chuo-ku, Tokyo Moriya Steel Machinery Co., Ltd. 72) Inventor Kazuhito Narita 1-5-8 Yaesu, Chuo-ku, Tokyo Moriya Koki Co., Ltd. F term (reference) 2D041 GB01 GC05 GC06 GC12 GC12 GC14

Claims (3)

[Claims] 1. A partially unbonded PC steel stranded wire composed of an unbonded tube partially filled with an anticorrosive oil and covered with an anticorrosion tube, and prevented by a water stop treatment at the end of the anticorrosion tube. In addition to isolating the inside and outside of the rust pipe, the grout hose passed through the inside of the rust prevention pipe grouts both inside and outside the rust prevention pipe. Cover the end of the specified tip-side uncoated portion from the tip to the coating tip with a rust-proof tube of a corresponding length, and seal the tip of this rust-proof tube under a predetermined water stoppage treatment. Also, each end of the cloth packer, which is arranged on the peripheral surface of the unbonded PC steel stranded wire from the rear end peripheral surface of the rust preventive pipe, is connected to each overlapping portion with a water stopping process, By fixing, this partially unbonded PC steel An uncurtain-don structure of a double rust-proof permanent anchor characterized by forming a capsule-shaped rust-preventive body isolated between the inside and outside of the rust-prevention pipe at the non-coating part on the leading end side of the wire. 2. A partially unbonded PC steel stranded wire formed by partial coating with an unbonded tube accompanied by filling with rust preventive oil is covered by a rust preventive tube, and is prevented by a water stop treatment at the end of the rust preventive tube. In addition to isolating the inside and outside of the rust pipe, the grout hose passed through the inside of the rust prevention pipe grouts both inside and outside the rust prevention pipe. Cover the end of the specified tip-side uncoated portion from the tip to the coating tip with a rust-proof tube of a corresponding length, and seal the tip of this rust-proof tube under a predetermined water stoppage treatment. Also, each end of the cloth packer, which is arranged on the peripheral surface of the unbonded PC steel stranded wire from the rear end peripheral surface of the rust preventive pipe, is connected to each overlapping portion with a water stopping process, By fixing, this partially unbonded PC steel Form a capsule-shaped rust preventive body isolated between the inside and outside of the rust preventive pipe on the non-covered part of the wire tip side, and partially unbond the support plate placed at the head fixing part.
It is formed in a form having insertion holes of the number corresponding to the number of PC steel strands, and is placed over the rear end side uncoated part and the coating part defined on the rear end side of the partially unbonded PC steel strand. A double rust-proof permanent anchor characterized by arranging a joint rust prevention pipe around it with water stoppage treatment and inserting each unbonded PC steel stranded wire into each insertion hole of this support plate Uncurtain don structure. 3. A rustproof joint pipe is formed into a substantially T-shaped side surface having an outer flange at an end on a side of a head fixing portion, and a concave step portion capable of storing the outer flange is provided with an outer flange. 3. An uncurtain-don structure for a double rust-proof permanent anchor according to claim 1 or 2, wherein the shape is shallower than the thickness of the anchor and is formed continuously with the opening of the supporting plate.