JP5993758B2 - Anchor bolt anchorage structure and construction method - Google Patents

Description

  The present invention relates to a structure of a fixing portion and a construction method for fixing an anchor bolt to a foundation.

  In various factories, it is common to install large equipment as production equipment on a reinforced concrete foundation and fix it with anchor bolts. The construction method and the anchor bolt replacement method are disclosed in Patent Document 1, and the outline thereof is shown in FIGS.

  This is the structure shown in FIGS. 8 to 11 (however, FIG. 8 shows a state in which a work space 7 for exchanging the anchor bolt 2 has already been constructed on the ground below the foundation 1, and FIG. An example of application when the existing anchor bolt 2 installed in the foundation 1 in the state before constructing the space 7 is replaced with a new anchor bolt 2 by the method shown in FIGS. As shown in FIGS. 10 (a), 10 (b), and 10 (c), the nut 3 can be screwed onto the base end (upper end) of the shaft portion 2a as the anchor bolt 2 (base bolt in Patent Document 1). The tip 1 (lower end) is a reverse T-shaped one having a rectangular convex portion 2b (which is a locking portion in Patent Document 1) protruding on both sides in the radial direction. In Reference 1, the anchor sleeve is embedded and the bottom of the anchor plate is anchored. 5 in advance provided (Patent Document 1 engaged bracket), is obtained so as to fix engaged convex portion 2b of the front end of the anchor bolt 2 relative to the anchor plate 5.

  As shown in FIGS. 9, 11A and 11B, the anchor plate 5 is formed with a rectangular through hole 5a through which it can penetrate in the center portion corresponding to the convex portion 2b of the anchor bolt 2. In addition, the bottom surface of the anchor plate 5 is formed with a similarly rectangular groove portion 5b formed in a direction orthogonal to the through hole 5a, and the convex portion 2b of the anchor bolt 2 is passed through the through hole 5a. After the anchor plate 5 is positioned below the anchor plate 5, the anchor bolt 2 is rotated 90 ° around the axis and pulled up to engage the convex portion 2 b with the groove portion 5 b, as shown in FIGS. 8 and 9. A nut 3 is screwed into a base plate 6 of various devices installed on the foundation 1 through an upper end portion of a shaft portion 2a of the anchor bolt 2 to be tightened.

And in patent document 1, when exchanging the existing anchor bolt 2 installed with the above structure with a new anchor bolt 2, the lower ground of the foundation 1 is excavated as shown in FIG. In addition, after securing the work space 7, the anchor bolt 2 is replaced by work from the work space 7.
In the following description, the anchor bolt 2 is distinguished from the existing anchor bolt 2A before replacement and the new anchor bolt 2B after replacement, and the anchor plate 5 is distinguished from the existing anchor plate 5A and the new anchor plate 5B.

That is, first, as shown in FIG. 12, the bottom of the foundation 1 is drilled by a core boring method directly under the sheath tube 4 and the bottom lid 4a (see FIG. 9) of the sheath tube 4 is cut to form the working hole 8. Then, the existing anchor bolt 2A is suspended in the work space 7 through the work hole 8, and the existing anchor bolt 2A is removed as shown in FIG.
Thereafter, the new anchor bolt 2B is lifted and installed in the sheath tube 4 through the working hole 8, and in that case, in Patent Document 1, the convex portion 2b of the new anchor bolt 2B is locked to the existing anchor plate 5A. Instead, as shown in FIG. 14, a new anchor plate 5B is mounted on the bottom surface of the foundation 1, and the convex portion 2b of the new anchor bolt 2B is fixed to the new anchor plate 5B.
In such a case, the length of the new anchor bolt 2B is made longer than the length of the existing anchor bolt 2A by the length corresponding to the distance between the existing anchor plate 5A and the new anchor plate 5B. It is necessary to keep. Further, in the example shown in FIG. 14, a lower cap 9 for preventing rust is attached to the new anchor plate 5B.

JP 2011-94385 A

By the way, for example, when replacing the old anchor bolt 2 with a new one, it may be desired to introduce a greater tension to the anchor bolt 2 after replacement than before replacement. When the anchor bolt 2 is replaced by the method shown in FIG. 14, it may be difficult.
That is, when the existing anchor bolt 2A is replaced with the new anchor bolt 2B by the conventional method shown in FIGS. 12 to 14, the fixed portion after the replacement has the structure shown in FIG. Since the work hole 8 formed for the replacement work is a cross-sectional defect part as it is above the newly installed anchor plate 5B newly installed on the bottom surface, only the peripheral edge of the newly installed anchor plate 5B is pressed against the foundation 1. Therefore, it is assumed that sufficient fixing strength cannot be secured depending on the concrete strength of the existing foundation 1 and the diameter of the work hole 8.

  Therefore, it is not preferable to apply such a replacement method when the anchor bolt 2 is replaced for the purpose of enhancing the fixing strength, and also when the anchor bolt 2 is replaced for other purposes, the fixing strength is not improved. Not being able to reinforce is not only unreasonable, but also somewhat difficult to ensure the reliability and safety of the fixing unit.

  In view of the above circumstances, an object of the present invention is to provide an effective and suitable fixing portion structure capable of giving sufficient fixing strength to a newly installed anchor bolt that is replaced in place of an existing anchor bolt, and a construction method thereof. To do.

  According to the first aspect of the present invention, the convex portion disposed at the lower end portion of the sheath tube embedded in the existing foundation is locked to the existing anchor plate embedded in the bottom portion of the foundation. An anchor bolt fixing portion structure applied when replacing an existing anchor bolt that has been fixed in a fixed state with a new anchor bolt, and a work hole through which the new anchor bolt can be inserted into the bottom of the foundation From the bottom surface of the foundation to a position that leads to the sheath tube, a new anchor bolt is inserted into the sheath tube and the working hole, and the new anchor is mounted on the new anchor plate attached to the open end of the working hole. The convex part provided at the tip of the bolt is locked, and a grout is filled between the new anchor plate and the existing anchor plate. It is hardened, and the edge of the new anchor bolt is wound with an edge-cutting material that cuts off the adhesion of the grout to the new anchor bolt, and a spiral line embedded in the grout is mounted. It is characterized by.

  According to a second aspect of the present invention, there is provided the anchor bolt fixing portion structure according to the first aspect, wherein a cover having a grout inlet and a grout outlet is attached to the new anchor plate, and the grout is passed through the cover. Is filled between the new anchor plate and the existing anchor plate and hardened, and in the grout, an upper end is opened at the position of the existing anchor plate and a lower end is provided in the cover. A grout discharge hose connected to the discharge port is buried.

  The invention according to claim 3 is arranged in a sheath tube embedded in an existing foundation, and a convex portion provided at the lower end thereof is locked to an existing anchor plate embedded in the bottom of the foundation. A method for constructing a fixing portion of an anchor bolt applied when replacing an existing anchor bolt that has been fixed in a fixed state with a new anchor bolt, in which the new anchor bolt can be inserted into the bottom of the foundation A hole is formed from the bottom surface of the foundation to a position communicating with the sheath tube, and a new anchor bolt is inserted into the sheath tube and the working hole, and the new anchor plate mounted on the open end of the working hole is inserted into the new anchor plate. The convex part provided at the tip of the anchor bolt is locked, and a grout is filled between the new anchor plate and the existing anchor plate. When the new anchor bolt is inserted into the sheath tube and the working hole, an edge cutting material for cutting off the adhesion of the grout to the new anchor bolt is previously provided at the tip of the new anchor bolt. In addition to winding, a spiral line embedded in the grout is attached, and the new anchor bolt is tensioned after the grout is hardened.

  According to a fourth aspect of the present invention, there is provided the anchor bolt fixing portion construction method according to the third aspect, wherein when the grout is filled, a cover having a grout inlet and a grout outlet is attached to the new anchor plate. In addition, a grout discharge hose that is connected to a grout discharge port that has an upper end opened at the position of the existing anchor plate and a lower end provided in the cover is attached to the tip of the new anchor bolt in advance, Pressurizing and injecting the grout into the cover from the grout inlet and continuing to pressurize the grout into the cover until the grout is discharged from the grout outlet through the grout discharge hose. Features.

  According to the present invention, after the convex portion at the tip of the new anchor bolt is locked to the new anchor plate, the grout is filled between the existing anchor plate and the new anchor plate and hardened for replacement work. It is possible to seal the working hole formed in step 1 with the grout and fix the tip of the new anchor bolt to the grout, thereby increasing the fixing strength compared to before the replacement.

FIG. 3 is a cross-sectional view illustrating a structure of a fixing unit according to an embodiment of the present invention. It is a figure which shows a newly installed anchor bolt. The cover is shown, wherein (a) is a top view, (b) is a cross-sectional view, and (c) is a bottom view. The procedure of the construction method of the fixing part which is embodiment of this invention is shown, (a) is the state of the existing anchor bolt, (b) is the state which is forming the work hole, (c) is forming the work hole. It is a figure which shows the state which carried out. (A) is a state in which the existing anchor plate is removed, (b) is a state in which the concrete in the sheath tube is removed and the existing anchor bolt is being removed, and (c) is a view showing a state in which the existing anchor bolt is removed. It is. (A) shows the state where the edge-cutting material, grout discharge hose and spiral reinforcement are attached to the new anchor bolt, (b) shows the state where the new anchor plate is attached to the new anchor bolt, and (c) shows the state where the new anchor plate is attached to the bottom of the foundation. It is a figure which shows the state mounted | worn to. (A) is the state which attached the cover, (b) is a figure which shows the state which is being filled with grout. It is a whole sectional view of the foundation for showing the structure of the fixing part of the conventional anchor bolt. It is a cross-sectional detail drawing which shows the structure of the fixing part of an anchor bolt. It is a figure which shows an anchor bolt, Comprising: (a) is a top view, (b) is a side view, (c) is a bottom view. It is a figure which shows an anchor plate, Comprising: (a) is a top view (XIa-XIa line view in FIG. 9), (b) is a bottom view (XIb-XIb line view in FIG. 9). It is sectional drawing which shows the state which is removing the existing anchor bolt same as the above. It is a figure which shows the state which removed the existing anchor bolt. It is a figure which shows the state after replacing | exchanging to a new anchor bolt same as the above.

Hereinafter, an embodiment of the anchor bolt fixing portion structure and construction method according to the present invention will be described with reference to FIGS.
In addition, this embodiment is an application example in the case where the existing anchor bolt 2A that is basically installed with the structure shown in FIGS. 8 to 11 is replaced with the new anchor bolt 2B by the method shown in FIGS. Therefore, among the components in the present embodiment, those corresponding to the components already described in FIGS. 8 to 14 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 1 shows the structure of the fixing portion of this embodiment, FIG. 2 shows a new anchor bolt 2B used in this embodiment, and FIG. 3 shows a cover 13 for grout filling used in this embodiment. It is.

In the present embodiment, as shown in FIG. 8, after excavating the lower ground of the foundation 1 to secure the work space 7, first, the existing anchor bolt 2 </ b> A and the new installation are made through the sheath tube 4 at the bottom of the existing foundation 1. The working hole 8 into which the anchor bolt 2B can be inserted is formed, and the existing anchor bolt 2A is extracted from the sheath tube 4 through the working hole 8 into the working space 7, and then the new anchor bolt 2B is inserted into the sheath tube 4 through the working hole 8. Inserted into the sheath tube 4 and the working hole 8 and disposed, and the convex portion 2b provided at the tip of the new anchor bolt 2B is mounted on the open end of the working hole 8 on the bottom surface of the foundation 1. It is based on locking with respect to the new anchor plate 5B.
In addition, in this embodiment, the grout 10 such as non-shrink mortar is filled between the new anchor plate 5B and the existing anchor plate 5A and hardened to seal the work hole 8 with the grout 10, and the new anchor bolt The main object is to fix the tip of 2B to the grout 10 and fix it firmly.

That is, in the present embodiment, as in the conventional structure after replacement shown in FIG. 14, the convex portion 2b provided at the tip of the new anchor bolt 2B is attached to the new anchor plate 5B attached to the bottom surface of the foundation 1. In addition, the cover 13 (see FIG. 3) also serves as a conventional anti-rust lower cap 9 (see FIG. 14) for the new anchor plate 5B. The details of this will be described later), and the grout 10 is filled between the new anchor plate 5B and the existing anchor plate 5A through the cover 13 and hardened.
As a result, the working hole 8 is not left as a hollow as in the conventional structure shown in FIG. 14, but is sealed by the grout 10, and the new anchor bolt 2B has the convex portion 2b at the tip of the new anchor. In addition to being locked to the plate 5B, the tip end portion of the shaft portion 2a is fixed to the bottom portion of the foundation 1 through the grout 10 over a wide range and firmly fixed thereto.
In this case, since the new anchor plate 5B, the existing anchor plate 5A, and the entire grout 10 filled therebetween are structurally integrated, the reaction force against the tension introduced into the new anchor bolt 2B is the new anchor plate 5B. Not only that, but the whole of them bears, so that it is possible to sufficiently enhance the fixing strength of the tip of the new anchor bolt 2B with respect to the foundation 1 as compared with the conventional structure shown in FIG.

In the present embodiment, the grout 10 is not simply filled between the new anchor plate 5B and the existing anchor plate 5A, but the tip of the new anchor bolt 2B is embedded in the grout 10. A spiral line 11 is arranged, and an edge cutting member 12 for cutting off the adhesion of the grout 10 is wound around the tip of the newly installed anchor bolt 2B.
That is, the tension of the new anchor bolt 2B is performed after the grout 10 is hardened. However, if the grout 10 is firmly attached to the new anchor bolt 2B at that time, there is a concern that an excessive stress is generated on the grout 10. Therefore, in this embodiment, in order to prevent this, as shown in FIG. 2, the edge cutting material 12 for cutting off the adhesion of the grout 10 is wound around the peripheral surface of the tip portion 2a of the new anchor bolt 2B. . Therefore, a desired tension force can be introduced to the new anchor bolt 2B without any trouble, and unnecessary tension is not generated on the grout 10 during the tension, and the spiral muscle 11 is arranged in the grout 10. In combination with this, the strength of the fixing portion can be sufficiently secured.

  Furthermore, in this embodiment, the grout 10 is pressed upward through the cover 13 attached to the new anchor plate 5B so that the grout 10 can be reliably and densely filled between the new anchor plate 5B and the existing anchor plate 5A without gaps. In addition, a grout discharge hose 14 is assembled at the tip of the newly installed anchor bolt 2B as shown in FIG. 2 to confirm that the grout 10 has been reliably filled to a predetermined level. (This point will be described in detail below).

Hereinafter, the construction method of the fixing unit having the above structure will be described with reference to FIGS.
FIG. 4A shows the installation state of the existing anchor bolt 2A to be replaced. This is substantially the same structure as in FIG. 9 and the existing anchor bolt 2A is installed, but the lower ground of the foundation 1 has already been excavated to secure the working space 7, and the existing anchor plate 9 is different from FIG. 9 in that the sheath tube 4 above 5A is filled with concrete 20 and the sheath tube 4 below the existing anchor plate 5A is filled with unnecessary materials such as resin and dust. is there.

  From the state shown in FIG. 4 (a), first, as shown in FIG. 4 (b), the bottom portion of the foundation 1 is drilled by the core boring method immediately below the sheath tube 4, and as shown in FIG. 4 (c). The bottom lid 4a of the sheath tube 4 is excised to remove unnecessary material from the bottom of the sheath tube 4, thereby forming a working hole 8 for extracting the existing anchor bolt 2A.

If the sheath tube 4 is hollow as in the conventional structure shown in FIG. 9, the existing anchor bolt 2A can be pulled out as it is as shown in FIG. In this embodiment, the concrete 20 is filled in the sheath tube 4, and the existing anchor bolt 2A cannot be pulled out as it is.
Therefore, in this embodiment, as shown in FIG. 5 (a), core boring is performed on the existing anchor plate 5A from the inside of the working hole 8, and the central portion is excised leaving the peripheral edge, and the sheath tube Core boring is also performed on the concrete 20 in 4 to cut the center from the peripheral edge at the position indicated by the chain line.
As a result, the existing anchor bolt 2A can be extracted. Therefore, as shown in FIG. 5B, the concrete at the center is removed from the sheath tube 4 and then the existing anchor bolt 2A is extracted or the existing anchor bolt 2A is removed. 5 and the concrete 20 adhering thereto are extracted together, the state shown in FIG. 5C is obtained, which is substantially the same state as in FIG.

  Therefore, the new anchor bolt 2B is inserted into the sheath tube 4 through the working hole 8, and basically the convexity of the new anchor bolt 2B with respect to the new anchor plate 5B mounted on the bottom surface of the foundation 1 as shown in FIG. The portion 2b is locked. At that time, the edge cutting member 12 is wound around the tip portion of the shaft portion 2a of the new anchor bolt 2B, and the grout discharge hose 14 is assembled, and the spiral muscle 11 is attached in advance. Further, a grout filling cover 13 is attached to the newly installed anchor plate 5B.

Specifically, as shown in FIG. 2, a tape-shaped edge cutting member 12 is spirally wound around the range where the grout 10 at the tip of the newly installed anchor bolt 2B is filled, and the outer side thereof is wound outside. For example, a flexible grout discharge hose 14 having a small diameter of about 20 mm is attached and assembled with a fixture such as a tape.
At this time, the position of the upper end of the grout discharge hose 14 is opened at a position slightly above the existing anchor plate 5A, and the lower end is pulled out below the new anchor plate 5B and connected to the cover 13 at a later stage. So make sure you have enough extra length for that.

Then, as shown in FIG. 6 (a), the spiral reinforcement 11 is attached to the tip of the new anchor bolt 2B, and the new anchor plate 5B is locked to the tip of the new anchor bolt 2B as shown in FIG. 6 (b). Then, the tip of the grout discharge hose 14 is drawn downward through a gap between the convex portion 2b of the new anchor bolt 2B and the new anchor plate 5B (that is, the through hole 5a formed in the new anchor plate 5B).
Then, the new anchor bolt 2B is inserted through the sheath tube 4 and the working hole 8, and the new anchor plate 5B is brought into close contact with the bottom surface of the foundation 1 as shown in FIG. At that time, the new anchor plate 5B can be pressed against the bottom surface of the foundation 1 by temporarily tensioning the new anchor bolt 2B. If necessary, the new anchor plate 5B can be pressed by a suitable fixing means such as a chemical anchor. It may be fixed against. Moreover, what is necessary is just to fill the clearance gap between the newly installed anchor plate 5B and the bottom face of the foundation 1 with the sealing material 15, such as a non-shrink mortar, as needed.

  Further, as shown in FIG. 7A, the cover 13 is attached to the new anchor plate 5B. The cover 13 may be attached to the new anchor plate 5B at the stage shown in FIG. 6B (that is, when the new anchor plate 5B is locked to the new anchor bolt 2B), or Furthermore, the cover 13 may be previously attached to the newly installed anchor plate 5B before that.

As shown in FIGS. 3A to 3C, the cover 13 used in the present embodiment is a rectangular hollow box having an open upper surface, and each peripheral surface thereof is formed on each peripheral surface of the newly installed anchor plate 5B. The flange is formed to be in close contact with each other, and the flange formed at the upper part is brought into close contact with the bottom surface of the newly installed anchor plate 5B and fixed thereto with anchor bolts or the like.
A grout inlet 13a and a grout outlet 13b are respectively provided on the two opposing surfaces of the peripheral surface of the cover 13, and the grout inlet 13a has an injection socket 13c that protrudes outside the cover 13. In addition, a discharge socket 13d is provided in the grout discharge port 13b toward the inside of the cover 13, and the grout discharge hose 14 can be connected to the discharge socket d.

As shown in FIG. 7A, after connecting the lower end of the grout discharge hose 14 assembled to the tip of the new anchor bolt 2B to the discharge socket 13d, the cover 13 is attached to the new anchor plate 5B. 7 (b), a grout supply hose (not shown) is connected to the injection socket 13c, and the grout 10 is inserted into the cover 13 from the grout inlet 13a. Inject under pressure.
As a result, the grout 10 pressurized and injected into the cover 13 fills the entire cover 13, and then the convexity of the new anchor plate 5B and the new anchor bolt 2B as shown by the arrows in FIG. 7B. When it is gradually pushed upward through a gap with the portion 2b (that is, the through-hole 5a formed in the new anchor plate 5B) and reaches a level slightly above the existing anchor plate 5A. At that time, excess grout 10 is discharged from the grout discharge port 13b to the outside of the cover 13 through the grout discharge hose 14. By continuing to fill the grout 10 up to that point, the grout 10 is located above the existing anchor plate 5A. It can be visually confirmed that it has been reliably filled to the position.

  After the grout 10 has hardened after a predetermined curing time, the new anchor bolt 2B is tensioned and a desired tension is introduced to complete the operation. At this time, as described above, the new anchor bolt 2B is insulated from the grout 10 by the edge cutting material 12, so that a desired tension can be imparted to the new anchor bolt 2B without any trouble, and the grout 10 can be provided. Unreasonable stress does not occur.

Although the embodiment of the present invention has been described above, the above embodiment is merely a preferred example, and the present invention is not limited to the above embodiment, and may be appropriately designed within the scope of the present invention. Changes and applications are possible.
For example, since the above embodiment is an application example when the sheath 20 is filled with the concrete 20, in order to extract the existing anchor bolt 2 </ b> A, as shown in FIGS. 5A and 5B, the existing anchor is used. The work of cutting the plate 5A and the concrete 20 in the sheath tube 4 is necessary. However, if the sheath tube 4 is a simple cavity as shown in FIG. In this case, the grout 10 may be filled between the existing anchor plate 5A and the new anchor plate 5B in the same manner as described above.

  Further, in the above embodiment, the grout 10 is filled through the cover 13 attached to the newly installed anchor plate 5B, and in this case, the grout filling state is confirmed by the grout discharge hose 14, but in the present invention, it is not always necessary. This is not the case, and the grout filling process may be performed by another process, and depending on the filling process, the confirmation process of the grout filling state may be omitted or performed by another method.

DESCRIPTION OF SYMBOLS 1 Foundation 2 Anchor bolt 2A Existing anchor bolt 2B Newly installed anchor bolt 2a Shaft part 2b Convex part 3 Nut 4 Sheath pipe 4a Bottom cover 5 Anchor plate 5A Existing anchor plate 5B New anchor plate 5a Through-hole 5b Groove part 6 Base plate 7 Work space 8 Work Hole 9 Lower cap 10 Grout 11 Spiral line 12 Edge cutting material 13 Cover 13a Grout inlet 13b Grout outlet 13c Injection socket 13d Discharge socket 14 Grout discharge hose 15 Sealing material 20 Concrete

Claims (4)

The convex portion provided at the lower end portion of the sheath tube embedded in the existing foundation was fixed in a state of being locked to the existing anchor plate embedded in the bottom portion of the foundation. The anchor bolt anchor structure applied when replacing an existing anchor bolt with a new anchor bolt,
Forming a working hole through which the new anchor bolt can be inserted into the bottom of the foundation from the bottom surface of the foundation to a position where it can communicate with the sheath tube, and inserting the new anchor bolt into the sheath tube and the working hole;
The convex portion provided at the tip of the new anchor bolt is locked to the new anchor plate attached to the opening end of the working hole, and a grout is provided between the new anchor plate and the existing anchor plate. Fill and harden,
An anchor characterized in that an edge cutting material for cutting off the adhesion of the grout to the new anchor bolt is wound around the tip of the new anchor bolt, and a spiral line embedded in the grout is mounted. Bolt fixing part structure. The anchor bolt fixing portion structure according to claim 1,
A cover having a grout inlet and a grout outlet is attached to the new anchor plate, and the grout is filled and hardened between the new anchor plate and the existing anchor plate through the cover.
Anchor fixing of an anchor bolt, wherein a grout discharge hose connected to a grout discharge port having an upper end opened at the position of the existing anchor plate and a lower end provided in the cover is embedded in the grout. Part structure. The convex portion provided at the lower end portion of the sheath tube embedded in the existing foundation was fixed in a state of being locked to the existing anchor plate embedded in the bottom portion of the foundation. It is a construction method of an anchor bolt fixing portion applied when an existing anchor bolt is replaced with a new anchor bolt,
Forming a working hole through which the new anchor bolt can be inserted into the bottom of the foundation from the bottom surface of the foundation to a position where it can communicate with the sheath tube, and inserting the new anchor bolt into the sheath tube and the working hole;
The convex portion provided at the tip of the new anchor bolt is locked to the new anchor plate attached to the opening end of the working hole, and a grout is provided between the new anchor plate and the existing anchor plate. Fill and harden,
When the new anchor bolt is inserted into the sheath tube and the working hole, an edge cutting material for cutting off the adhesion of the grout to the new anchor bolt is previously wound around the tip of the new anchor bolt. Along with the spiral muscles embedded in the grout,
The anchor bolt fixing portion is constructed by tensioning the new anchor bolt after the grout is cured. It is a construction method of the fixing part of the anchor bolt according to claim 3,
When filling the grout, a cover having a grout inlet and a grout outlet is attached to the new anchor plate, and an upper end opens at the position of the existing anchor plate at the tip of the new anchor bolt and a lower end A grout discharge hose connected to a grout discharge port provided in the cover is attached in advance,
Pressurizing and injecting the grout into the cover from the grout inlet and continuing to pressurize the grout into the cover until the grout is discharged from the grout outlet through the grout discharge hose. The anchor bolt fixing part construction method is a feature.

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