JP5266584B2 - Corrosion-proof PC steel wire assembly and anchor structure construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anchor structure using an anticorrosive PC steel stranded wire having excellent durability and achieving excellent workability in construction and to provide a construction method for the anchor structure. <P>SOLUTION: This anchor structure A1 is provided with the anticorrosive PC steel stranded wire 2, a corrugated sheath 4, primary grout, and secondary grout. The anticorrosive PC steel stranded wire 2 is made of a PC steel stranded wire 2t covered with a resin 2r and is provided with a free length part 3B stored in a cable sheath 2s and a fixed length part 3A exposed from the sheath 2s. The corrugated sheath 4 has a bottomed tubular shape, stores the anticorrosive PC steel stranded wire 2 while the fixed length part 3A of the anticorrosive PC steel stranded wire 2 is arranged on its bottom part side, and is arranged in a drilled hole H. The primary grout is filled into the corrugated sheath 4, and the fixed length part 3A is fixed in the corrugated sheath 4. The secondary grout is filled between the drilled hole H and the corrugated sheath 4 to fix the corrugated sheath 4 in the drilled hole H. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an anchor structure using an anticorrosion PC steel strand for improving the durability of an existing concrete structure, a method for constructing the anchor structure, and an anticorrosion PC steel wire assembly used in the anchor structure. Is. In particular, the present invention relates to an anchor structure for reinforcing a concrete structure that is difficult to be reconstructed, such as a dam, a breakwater, and an underground station building, a method for constructing the anchor structure, and an anticorrosion PC steel wire assembly.

  Conventionally, an anchor structure for reinforcing a slope of a retaining wall is known (for example, see Patent Document 1). This anchor structure is configured by fixing a plurality of anticorrosion PC steel wires arranged in the drilling hole formed on the slope of the retaining wall, which is the construction surface, to be fixed at the opening of the drilling hole in a tensioned state. . And this anchor structure reinforces a retaining wall by providing tension | tensile_strength of a wire from each anticorrosion PC steel as a compressive force to a construction surface.

  FIG. 4 is a diagram illustrating an example of an anchor structure. A method for forming such an anchor structure will be described below.

  In order to form the anchor structure B, first, a plurality of anticorrosion PC steel wires 110 are arranged in a hole H formed from the concrete construction surface S covering the surface of the ground G toward the ground G. Each anticorrosion PC steel strand 110 is accommodated in one sheath 130 in a state of being separated from each other by a spacer 120. When the wire 110 is placed in the hole H from the anticorrosion PC steel, one end side of the sheath 130 is peeled off by a predetermined length, and the strand 110 is exposed at that portion. At the end of the peeled sheath 130, a water stop portion 140 that seals the gap between the sheath 130 and the strand 110 is formed.

  Next, the end of the anticorrosion PC steel wire 110 exposed to the outside from the hole H is temporarily fixed to the ground G with the anchor disk D and the anchor plate P, and the hole H is sealed. When the arrangement of the stranded wire 110, the anchor disk D, and the anchor plate P is completed, the grout is injected into the hole H. When a predetermined time has elapsed from filling of the grout H to the grout, the grout is cured. Here, the illustrated anticorrosion PC steel stranded wire 110 has an exposed portion (fixing length portion) and a portion covered by the sheath 130 (free length) with the water stop portion 140 sealing the opening of the sheath 130 as a boundary. Part). Therefore, when the grout is hardened, only the exposed portion of the strand 110 is fixed to the hole H.

  Finally, the anticorrosion PC steel wire 110 protruding from the anchor disk D is tensioned and fixed to the anchor disk D with the wedge W, thereby completing the anchor structure B. The tension applied to the stranded wire 110 is transmitted to the construction surface S via the wedge W, the anchor disk D, and the anchor plate P.

Japanese Patent Laid-Open No. 5-125656

  In recent years, based on the lessons learned from the Great Hanshin-Awaji Earthquake, anchor structures have been applied to concrete structures that cannot be easily remodeled, such as existing dams, breakwaters, and underground station buildings. It is recommended to do. When an anchor structure is applied to such a concrete structure, a required characteristic is to have long-term reliability, that is, durability. However, if the conventional anchor structure such as Patent Document 1 described above is applied to the reinforcement of a concrete structure such as a dam as it is, the durability of the anchor structure may not be sufficient.

  As shown in FIG. 4, the exposed portion (fixed length portion) of the anticorrosion PC steel wire 110 is only covered by the grout, so that the water exuding from the ground G into the hole H can be prevented. It is hard to say that all waterproofing measures are taken. If the stranded wire 110 is rusted, the durability of the anchor structure B is lowered. Therefore, it is important to take a waterproof measure against the bare stranded wire 110. In particular, in the anchor structure B provided in a concrete structure such as a dam or a breakwater in an environment where a large amount of water exists, it is expected that the importance of waterproofing measures is high.

  Further, when the hole H is formed in the concrete structure, since the inner peripheral surface of the hole H is hard, there is a possibility that the exposed anticorrosion PC steel wire 110 contacts the inner peripheral surface of the hole H and is damaged. is there. Therefore, it is necessary to carefully insert the stranded wire 110 into the hole H, and workability when constructing the anchor structure B is not good.

  The present invention has been made in view of the above circumstances, and one of its purposes is an anchor structure using a corrosion-resistant PC steel wire having high durability and excellent workability in construction, and construction of this anchor structure. It is to provide a method. Another object of the present invention is to provide a wire assembly made of anticorrosion PC steel suitable for construction of the anchor structure.

<Anchor structure>
The present invention fixes the wire tension from the anti-corrosion PC steel to the construction surface by fixing the wire to the opening of the hole in a state where the wire is tensioned from the anti-corrosion PC steel arranged in the hole formed on the construction surface. The present invention relates to an anchor structure using a stranded anticorrosion PC steel wire to be applied as a compression force. The anticorrosion PC steel strand provided in the anchor structure is made of a resin-coated PC steel strand and includes a free length portion accommodated in the cable sheath and a fixing length portion exposed from the cable sheath. The anchor structure of the present invention has a bottomed tubular shape, and stores at least the fixing length of the anticorrosion PC steel strand on the bottom side and is disposed in the drilling hole, and is filled in the corrugated sheath. A primary grout that fixes the fixing length to the corrugated sheath, and a secondary grout that is filled between the drilled hole and the corrugated sheath and fixes the corrugated sheath to the drilled hole.

  By adopting the configuration of the present invention, the fixing length of the wire from the anticorrosion PC steel in the drilling hole is covered with the corrugated sheath and is not exposed, so the wire corrodes very much from the anticorrosion PC steel. hard. In addition, since the anchoring length portion of the anticorrosion PC steel wire in the anchor structure of the present invention is protected by the corrugated sheath during the construction work of the anchor structure, it is arranged with almost no damage. Therefore, the anchor structure of the present invention has very high durability, and can continuously apply a predetermined tension force to the construction surface over a long period of time.

<Anti-corrosion PC steel strand assembly>
The anticorrosion PC steel strand assembly of the present invention includes an anticorrosion PC steel strand, a cable sheath, a corrugated sheath, and a spacer. The anticorrosion PC steel strand consists of a resin-coated PC steel strand. The cable sheath is tubular and accommodates a part of the anticorrosion PC steel strand, so that one end of the anticorrosion PC steel wire including the accommodated portion is exposed at the free length of the anticorrosion PC steel wire. The other end side of the anticorrosion PC steel wire is defined as the fixing length of the anticorrosion PC steel wire. The corrugated sheath has a bottomed tubular shape and accommodates at least a fixing length portion of the anticorrosion PC steel wire on the bottom side. The spacer positions the strands of the anticorrosion PC steel in the corrugated sheath. In addition, the inside of a cable sheath, ie, between a cable sheath and anticorrosion PC steel strand, is normally filled with the anticorrosion material.

  The stranded anticorrosive PC steel housed in the corrugated sheath may be singular or plural. Moreover, it is preferable that a plurality of spacers are arranged at intervals in the longitudinal direction of the corrugated sheath. Here, when there is a single stranded wire from the anticorrosive PC steel, the spacer positions the wire from the anticorrosive PC steel so that the stranded wire from the anticorrosive PC steel does not contact the inner peripheral surface of the corrugated sheath. Moreover, when there are a plurality of strands of anticorrosion PC steel, the spacer keeps the wires from each anticorrosion PC steel in a separated state while preventing contact between each anticorrosion PC steel and the corrugated sheath inner peripheral surface.

  According to the anticorrosion PC steel wire assembly of the present invention, since the fixing length portion of the anticorrosion PC steel wire is covered with the corrugated sheath, when inserting the wire from the anticorrosion PC steel into the drilling hole, the fixing length The part is hardly damaged. In addition, when the anticorrosion PC steel strand is placed in the drilling hole and the anchor structure is constructed, the fixing length is protected by at least triple anticorrosion structure (resin coating / corrugated sheath / primary grout in the corrugated sheath). Will be. Therefore, the anchor structure formed using the anticorrosion PC steel strand of the present invention is very durable and can continue to impart a predetermined tension to the construction surface over a long period of time.

  In the anticorrosion PC steel wire assembly of the present invention, a partition member may be provided that seals the open end side of the corrugated sheath and partitions the region inside the corrugated sheath from the region outside.

  If it is the said structure, as shown in Embodiment 2 mentioned later, the length of a corrugated sheath can be shortened. Further, by shortening the corrugated sheath, the amount of primary grout filled in the corrugated sheath when constructing the anchor structure can be reduced. As will be described later, since the primary grout is preferably filled at a high pressure, if the filling amount can be reduced, the labor for constructing the anchor structure can be reduced.

  In the anticorrosion PC steel wire assembly according to the present invention, it is preferable that a delayed curing resin is filled between the cable sheath and the resin-coated anticorrosion PC steel wire.

  When an anchor structure is constructed using a wire assembly from the anticorrosion PC steel, the wire is fixed over almost the entire length of the anticorrosion PC steel in a tensioned state. Therefore, the tension of the wire is less likely to loosen from the anticorrosion PC steel over a long period of time. Here, the delayed curing resin also functions as an anticorrosive material.

  In the anti-corrosion PC steel wire assembly of the present invention, a rust-proof material that does not harden over time may be filled between the cable sheath and the resin-coated anti-corrosion PC steel wire.

  When an anchor structure is constructed using a wire assembly from the anticorrosion PC steel, the wire is not restrained by the anticorrosion PC steel by the anticorrosive material, so that the stranded wire can be re-tensioned. Therefore, if the wire is re-tensioned from the anticorrosion PC steel every predetermined period, a predetermined tension can be applied to the construction surface over a long period of time.

<Construction method of anchor structure>
Moreover, the anchor structure for reinforcing the said structure can be constructed by applying a compressive force to the concrete structure using the wire assembly from the anticorrosion PC steel of the present invention. That is, the present invention is a method of constructing an anchor structure for reinforcing a concrete structure by applying prestress to a concrete structure installed on the ground, and includes the following steps.
-A process of forming a drilling hole that penetrates the concrete structure from the construction surface of the concrete structure and reaches the ground.
-Inserting a wire assembly from the anticorrosion PC steel of the present invention into the drilling hole and arranging the fixing length of the anticorrosion PC steel wire at a position in the ground
A step of filling the corrugated sheath with a primary grout for fixing the fixing length to the corrugated sheath.
A step of filling the hole with a secondary grout for fixing the corrugated sheath to the hole.
-After hardening the primary grout and secondary grout, the process of tensioning the free length side end of the wire from the anticorrosion PC steel and fixing it to the construction surface.

  According to the anchor structure construction method of the present invention, an anchor structure having a predetermined durability can be constructed. In particular, in the anticorrosion PC steel wire assembly of the present invention used in this method, the fixing length of the anticorrosion PC steel wire is protected by a corrugated sheath, and when inserting the stranded wire into the drilling hole, Is not required to be careful. For this reason, the anchor structure construction method of the present invention is superior to the conventional method in terms of workability.

  The anchor structure of the present invention has very high durability, and can continue to impart a predetermined tension to the construction surface over a long period of time. Therefore, according to the anchor structure of the present invention, it is possible to reinforce a concrete structure that is difficult to be reconstructed, such as a dam, a breakwater, and an underground station building, and maintain the concrete structure over a long period of time.

The schematic which applied the anchor structure of this invention to the dam body (concrete structure) of a dam is shown. It is a schematic block diagram which shows the principal part of the anchor structure which concerns on Embodiment 1. FIG. It is a schematic block diagram which shows the principal part of the anchor structure which concerns on Embodiment 2. FIG. It is the schematic of the conventional anchor structure.

  Hereinafter, an example in which the anchor structure of the present invention is applied to reinforcement of a dam will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 shows a schematic view in which an anchor structure A1 of the present invention is applied to a dam body C (concrete structure). FIG. 2 is a schematic configuration diagram showing main parts of the anchor structure A1.

  First, the hole H is formed in the dam body C (see FIG. 1). The drilling hole H penetrates the dam body C and reaches the ground G at a position deeper than the dam body C.

  Next, the wire assembly 1 is prepared from the anticorrosion PC steel of the present invention (see FIG. 2). The anticorrosive PC steel strand assembly 1 includes a corrugated sheath 4, a plurality of anticorrosive PC steel strands 2 disposed in the corrugated sheath 4, and a spacer 5.

  The anticorrosion PC steel strand 2 is a PC steel strand 2t having a resin coating 2r on its surface as a countermeasure against corrosion, and is housed in a tubular cable sheath 2s. Further, a rust preventive material 2b (such as grease) is filled between the anticorrosion PC steel strand 2t and the sheath 2s. Examples of the material of the resin coating 2r include an epoxy resin. The cable sheath 2s is a tubular member having both ends opened, and is formed of a resin such as polyethylene, for example.

  The anticorrosion PC steel strand 2 is longer than the cable sheath 2s, and both ends of the strand 2 protrude from both open ends of the sheath 2s. That is, both ends in the longitudinal direction of the stranded wire 2 are exposed without being covered with the sheath 2s. As will be described later, one of the exposed portions of the twisted line 2 becomes a fixing length portion 3A in the anchor structure A1, and a portion other than the fixing length portion 3A (including the other exposed portion) becomes a free length portion 3B. This fixing length portion 3A is usually formed so as to be at the position of the ground G below the levee body C when the wire assembly 1 is disposed in the hole H from the anticorrosion PC steel. Further, the end of the cable sheath 2s on the fixing length 3A side is stopped by a sealing member such as a heat shrinkable tube.

  A corrugated sheath 4 for housing the above-described anticorrosion PC steel strand 2 is a bottomed tubular member having a structure in which one end side is opened and the other end side is sealed. From the opening of the corrugated sheath 4, one end of the anticorrosion PC steel wire 2 disposed in the corrugated sheath 4 (an exposed portion opposite to the fixing length 3 </ b> A and a part of the free length 3 </ b> B) Is protruding. Such a corrugated sheath 4 may be formed of a transparent resin such as polyethylene, or may be formed of a metal such as stainless steel. If the corrugated sheath 4 is made of a transparent resin, the arrangement state of the wire 2 from the anticorrosion PC steel in the corrugated sheath 4 can be confirmed. If the corrugated sheath 4 is made of metal, the strength of the corrugated sheath 4 can be ensured.

  Each anticorrosion PC steel strand 2 in the corrugated sheath 4 is held in a separated state by a spacer 5. A plurality of spacers 5 are provided in the corrugated sheath 4 at predetermined intervals. These spacers 5 are provided so as to partition the space in the corrugated sheath 4, but do not restrict the movement of the primary grout filled in the corrugated sheath 4 in a subsequent process.

  The spacer 5 can be disposed in the corrugated sheath 4 as follows, for example. First, an annular member having a plurality of through holes with an outer diameter smaller than the inner diameter of the corrugated sheath 4 is prepared. One anticorrosion PC steel wire 2 is inserted into each through hole of the annular member, and the gap between the through hole and the twisted wire 2 is sealed and integrated. Then, this integrated product is inserted into the corrugated sheath 4. In this case, the annular member becomes the spacer 5. The spacer 5 is also provided with a through hole in which the stranded wire 2 is not disposed, and the movement of the primary grout within the corrugated sheath 4 is not restricted as described above.

  In addition, it is preferable that the end of the wire 2 (2t) is not exposed by covering the end of the anticorrosion PC steel wire 2 on the fixing length portion 3A side with a cap, a heat shrink tube or the like.

  When the wire assembly 1 is prepared from the above-described anticorrosion PC steel, the joint pipe J is then attached to the open end of the corrugated sheath 4 of the assembly 1. The joint pipe J is provided with a bottomed pipe part and a flange part extending in the radial direction of the pipe part on the opening side of the pipe part, and the bottom of the pipe part can be penetrated by a single anticorrosion PC steel wire 2. Has holes. When the joint pipe J is attached to the corrugated sheath 4, the wire 2 is inserted through the through-hole of the pipe section, and a part of the pipe section is arranged inside the corrugated sheath 4. And the clearance gap between the through-hole of a pipe part and the strand 2 and the clearance gap between a pipe part and the corrugated sheath 4 are sealed, and area | region R1 inside the corrugated sheath 4 is divided from an external area | region.

  Next, the flat anchor plate P is disposed so as to contact the construction surface S. A through hole is formed in the center of the anchor plate P, and this through hole is larger than the diameter of the pipe portion of the joint pipe J described above and smaller than the outer diameter of the flange portion.

  Next, the wire assembly 1 is inserted into the hole H from the anticorrosion PC steel integrated with the joint pipe J through the through hole of the anchor plate P. At this time, the flange portion of the joint pipe J is engaged with the anchor plate P, the position of the wire assembly 1 is determined by the anticorrosion PC steel in the hole H, and the corrugated sheath 4 and the hole of the assembly 1 are determined. A region R <b> 2 between H is defined. Further, the fixing length portion 3A of the wire assembly 1 is arranged at a position completely surrounded by the ground G from the inserted anticorrosion PC steel. By setting the fixing length portion 3A in this way, prestress can be applied to the dam body C when the end portion on the free length portion 3B side of the wire 2 is tensioned and fixed.

  Further, the anchor disk D is disposed on the flange portion of the joint pipe J. The anchor disk D has a through hole into which the wire 2 can be inserted one by one at a position corresponding to the through hole of the joint pipe J. Therefore, if the anchor disk D is disposed in the flange portion of the joint pipe J, the strand 2 is disposed in a state of protruding from the through hole of the disk D, and a region R3 in the pipe portion of the joint pipe J is formed.

  When the wire assembly 1 is arranged from the anticorrosive PC steel in the drilling hole H, the region R1 of the corrugated sheath 4 is filled with cement-based primary grout, and the region R2 between the corrugated sheath 4 and the drilling hole H is filled. Fill with cement-based secondary grout. The primary grout may be injected by a communication pipe (not shown) communicating with the region R1 from the outside, for example, a hose penetrating the members D and J. In addition, the injection of the secondary grout is also performed by a communication pipe (not shown) communicating with the region R2 from the outside, for example, a hose that penetrates the members D and J and extends into the corrugated sheath 4 and penetrates the bottom of the corrugated sheath 4 Can be done.

  The primary grout and the secondary grout may be filled at the same time, or may be filled with a time difference. However, when providing a time difference, it is preferable to fill the primary grout first since the corrugated sheath 4 may be collapsed by the filling pressure of the secondary grout if the secondary grout is filled first.

  When both the filled primary grout and the secondary grout are hardened, the wire 2 is tensioned from the anticorrosion PC steel of the wire assembly 1 by the anticorrosion PC steel. Here, the fixing length portion 3A of the stranded wire 2 is fixed to the corrugated sheath 4 by primary grouting, and the corrugated sheath 4 is fixed to the drilling hole H by secondary grouting. For this reason, even if the stranded wire 2 is tensioned, the fixing length portion 3A maintains its position without substantially extending. On the other hand, the free length 3B of the stranded wire 2 can be extended because it is surrounded by a rust preventive material and is not fixed to the corrugated sheath 4.

  As described above, the stranded wire 2 is fixed to the anchor disk D by the wedge W in a state where the stranded wire 2 is tensioned. The fixed stranded wire 2 applies a compressive force to the construction surface S (that is, the bank body C) via the wedge W, the anchor disk D, the joint pipe J, and the anchor plate P.

  Finally, the anchor structure A1 is completed by filling the region R3 with a rust preventive material (or grout) from a filling hole (not shown) provided in the anchor disk D. The anchor structure A1 thus completed has high corrosion resistance because there is no portion where the fixing length 3A of the wire 2 is exposed in the hole H from the anticorrosion PC steel. That is, the stranded wire 2 is maintained in a healthy state over a long period of time, and a predetermined tension can be continuously applied to the dam body C. Moreover, since the free length part 3B of the strand 2 is not being fixed with respect to the cable sheath 2s, the anchor structure A1 of this embodiment can re-tension the strand 2.

<Embodiment 2>
An anchor structure having a corrugated sheath having a length different from that of the first embodiment will be described with reference to FIG. The anchor structure A2 of the present embodiment is the same as the anchor structure A1 of the first embodiment except that the design change of the corrugated sheath and the accompanying additional structure are provided. Accordingly, in the following description, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted.

  As shown in FIG. 3, the corrugated sheath 4 of the anchor structure A2 of the present embodiment is formed to have a length that accommodates the fixing length 3A and a part of the free length 3B on the fixing length 3A side. Has been. That is, the corrugated sheath 4 of this embodiment is significantly shorter than the corrugated sheath of the first embodiment. For example, in the anchor structure of the 100 m class, the corrugated sheath 4 is 80 m or shorter than that in the first embodiment. The other part of the free length portion 3B that is not covered by the corrugated sheath 4 is originally covered by the cable sheath 2s, so that it is difficult to be damaged and corroded.

  Further, in the anchor structure A2 of the present embodiment, the corrugated sheath 4 is shortened so that the opening end side of the corrugated sheath 4 is sealed so that the inner region R1 and the outer region R2 of the corrugated sheath 4 are separated. A partition member 6 for partitioning is provided. With such a configuration, the primary grout that fixes the fixing length portion 3A to the corrugated sheath 4 and the secondary grout that fixes the corrugated sheath 4 to the hole H can be filled separately. As a result, it is possible to firmly fix the fixing length portion 3A to the corrugated sheath 4 by filling the primary grout with high pressure. Moreover, since the filling volume of the primary grout is small, the filling pressure of the primary grout can be easily increased.

  If it is the structure demonstrated above, since the length of the corrugated sheath 4 is short, the manufacturing cost of the assembly 1 can be restrained lower than Embodiment 1. FIG. Moreover, since the assembly 1 is reduced in weight by the amount of the corrugated sheath 4, the assembly 1 is easy to handle during transportation from the factory to the site and installation on the site, and has an effect of reducing the construction cost of the anchor structure.

  In addition, this invention is not necessarily limited to embodiment mentioned above, In the range which does not deviate from the summary of this invention, it can change suitably. For example, the rust preventive material 2b filled between the cable sheath 2s and the anticorrosion PC steel strand 2 may be replaced with a delayed curing resin. In this case, after the resin is cured, the wire 2 cannot be re-tensioned from the anticorrosive PC steel, but the strained wire 2 can be fixed over almost the entire length, so that the tension of the wire 2 is not easily loosened. .

  The anchor structure of the present invention can be suitably used to reinforce concrete structures that are not easily remodeled, such as dams, breakwaters, and underground station buildings.

C Dam body (concrete structure) G Ground S Construction surface H Drill hole W Wedge D Anchor disk J Joint pipe P Anchor plate A1, A2 Anchor structure 1 Corrosion-proof PC steel wire assembly 2 Corrosion-proof PC steel wire 2t PC steel Strand 2r Resin coating 2s Cable sheath 2b Rust preventive material 3A Fixing length 3B Free length 4 Corrugated sheath 5 Spacer 6 Partition member R1 to R3 Region B Anchor structure 110 Corrosion-proof PC steel strand 120 Spacer 130 Sheath 140 Water stop

Claims (2)

Anti-corrosion PC steel wire consisting of resin-coated PC steel wire;
It is tubular, and by storing a part of the wire from the anticorrosion PC steel, one end of the wire from the anticorrosion PC steel including the stored portion is free from the anticorrosion PC steel, and from the exposed anticorrosion PC steel. A cable sheath that prescribes the other end of the wire as the fixing length of the wire from the anticorrosion PC steel;
A bottomed tubular corrugated sheath that houses therein a portion of the fixing length and the free length of the cable sheath up to the vicinity of the end opposite to the fixing length ;
Delayed-cure resin filled between the cable sheath and the anti-corrosion PC steel strand;
A spacer for positioning the wire from the anticorrosion PC steel in the corrugated sheath;
A wire assembly from an anti-corrosion PC steel characterized by comprising: A method for constructing an anchor structure for reinforcing a concrete structure by applying prestress to a concrete structure installed on the ground,
Forming a drilling hole that penetrates the concrete structure from the construction surface of the concrete structure and reaches the ground;
Inserting a wire assembly from the anti-corrosion PC steel according to claim 1 into the hole, and arranging a fixing length of the anti-corrosion PC steel wire at a position in the ground;
Filling the corrugated sheath with a primary grout for fixing the fixing length to the corrugated sheath;
Filling the hole with a secondary grout for fixing the corrugated sheath to the hole;
After hardening the primary grout and secondary grout, the step of tensioning the free length side end of the wire from the anticorrosion PC steel and fixing it to the construction surface;
An anchor structure construction method characterized by comprising:

Images