JP4953775B2 - Prestress introduction device and anchor structure thereof - Google Patents

Description

The present invention relates to a prestressing force introducing device provided with a PC steel material often used in civil engineering construction, and more particularly to a prestressing introducing device for small-diameter drilling and an anchor structure thereof .

  Conventionally, as shown in FIG. 5, a solid reaction force PC steel rod 7 is arranged in a hollow PC steel rod 6, and the reaction force PC steel rod 7 is applied with tension to the hollow PC steel rod 6. The anchor structure of the prestress introduction device 8a provided with a hollow PC steel bar for introducing prestress into the concrete as a reaction force body is as follows: (1) As shown in FIGS. FIG. 6 shows a case where fixing is performed by an end holder composed of an anchor member 32 and a male screw member 41 screwed into a male screw portion 20 at the front end portion of the PC steel rod 6 and a male screw portion 20 at the front end portion of the hollow PC steel rod 6. There is a method of fixing only by the male screw portion 20 at the front end portion of the hollow PC steel rod 6 (see, for example, Patent Documents 1 to 3).

  The structure of the prestress introduction device 8 shown in FIGS. 5 (a) and 5 (b) will be described briefly. While having a male screw portion 20 on the outer side in the longitudinal direction of the steel hollow PC steel rod body 6a (front end portion), The male screw portion 21 of the hollow PC steel rod 6 having the male screw portion 21 on the outer side of the other end (rear end portion) has female screw holes 22 and 23 at both front and rear ends and a polygonal outer surface 24 for engaging the rotary tool. A female screw hole 22 at the front end of the bearing cylinder 25 is screwed and connected.

  A front male screw portion 27 of a stopper 26 made of a steel tubular annular locking piece is screwed into the female screw hole 23 at the rear end portion of the support tube 25, and a rotation is provided outside the rear end portion of the stopper 26. A moving tool engaging outer surface 28 is formed.

  The front end portion of the stopper 26 is disposed inside the support cylinder 25, and the rear end surface of the press locking piece 30 having the concave portion 29 is engaged with the front end portion, and the concave portion 29 of the front end portion of the press locking piece 30 is engaged. In the hollow PC steel rod 6, almost the whole other than the other end side is inserted and the other end side is arranged so as to protrude from the other end portion of the hollow PC steel rod 6. (Repulsive force PC steel rod for non-pull) 7 is fitted to the rear end portion. Note that the non-pull means a system that does not pull out, in other words, a stationary system.

  An anchor member 32 made of a nut having a female threaded portion 31 is detachably screwed to the male threaded portion 20 outside the front end portion of the hollow PC steel rod 6, and the distal end portion of the pushing reaction force PC steel rod 7 is It is connected to the female screw part 31. A male screw member 41 is screwed and fixed to the anchor member 32, and the distal end portion of the reaction force PC steel rod 7 is supported by the male screw member 41.

  The prestress introduction device 8a currently used shown in FIG. 5 is a standard type, 20T (outside diameter of hollow PC steel rod 29 mm), 30T (outside diameter of hollow PC steel rod 32 mm), 40T (hollow PC steel rod) 40T), 60T (outside diameter of hollow PC steel rod 43mm), and the outer diameter of the anchor material 32 is 62.4mm, 67mm, 86.5mm, or 92.3mm, respectively. In the internal thread type in which the front end portion of the hollow PC steel rod 6 shown in FIG. 7 is an internal female thread, 20S (the thread of the male thread member 41 is equivalent to M24 and its length is 25 mm), 40S (the thread of the male thread member 41 is M35). The length is 35 mm), and an anchor nut (supporting member) 42 is attached to the male screw portion 20 for use. Such a prestress introduction device 8 can be sufficiently fixed by using any type of prestress introduction device 8a when embedded in concrete from the beginning or when a sufficient length is embedded. There is no strength problem.

However, when drilling a hole in an existing concrete structure and embedding the prestress introduction device 8a, if the drilled hole cannot have a sufficient length, or if the concrete in the existing concrete structure has low strength, The stress introduction device 8a and the filler filled in the hole, the filler and the concrete of the existing concrete structure must surely transmit the force.
Therefore, the male screw member 41 as an end holder plays an important role. As another form, a double nut has been developed outside the front end portion of the hollow PC steel rod 6. In order to transmit force to the filler and the concrete structure, it has also been developed to form a groove in the drilled hole.
Thus, the outer diameter of the end holder is large, and holes of about φ90 mm and φ110 mm are drilled to embed it.

In addition, when the front end side of the prestress introduction device 8a as described above is arranged and used in a connection hole or groove of a new concrete structure, a high strength concrete is used if necessary, so that prestress is introduced. If a high-strength filler such as non-shrink mortar that embeds the outer periphery of the front end side of the device 8a is used, the prestressing force introduced by the prestress introducing device 8a is applied to the concrete structure via the adhesive force with the filler. It was conveyed to things.
JP 07-139173 A JP 2001-207590 A JP-A-2005-90124

  In recent years, the demand for crimping other members to an existing structure has increased, but some existing structures have low-strength concrete structures, and the prestress introduction device 8a has been fixed to a concrete structure. Some structures are difficult to settle. In other words, if the concrete of the concrete structure is low-strength concrete, even if the filler that fixes the prestress introduction device 8a is high-strength, the low-strength concrete does not have the adhesion due to the adhesion between the filler and the low-strength concrete. Even if only the material is made to have high strength and the adhesion to the prestress introduction device 8a is secured, the prestress of the prestress introduction device 8a is not transmitted to the concrete for low strength concrete.

  That is, in the joining structure using the prestressing force introducing device 8a when the anchor hole provided in one concrete structure is a bag hole, the hollow PC steel rod 6 is joined by prestressing. When tensile acts, it is not affected by the strength of the hollow PC steel bar (PC steel material) 8a as it is, but the low-strength concrete changes from being compressed to tensile, and resists the tension to that strength. If the adhesion between the PC steel material and the filler (grouting) 5 is sufficient, but the adhesion between the filler 5 and one concrete structure cannot be expected sufficiently, a number of prestress force introduction devices 8a are provided. It becomes corresponding and becomes not economical.

  Also, some concrete structures are densely arranged with rebars. In that case, the diameter of the hole for fixing the prestress introduction device 8a is much larger than that of a hollow PC steel rod. It had to be larger than the outer diameter of the large end holder, and the rebar could not be cut.

  Usually, when the object to be drilled is a reinforced concrete structure, the arrangement of the reinforcing bars embedded in the concrete structure becomes a problem. Drilling must be done without cutting the embedded reinforcing bars. In the case of construction, the reinforcing bars that are embedded in the concrete are arranged with a pitch of 100 mm, 150 mm, and 200 mm between the hoop and scallop bars. The interval between the main bars embedded in the concrete may be arranged closer to the above-mentioned interval.

The interval between the reinforcing bars embedded in the concrete is the standard specification for building construction published by the Architectural Institute of Japan, and the same description. It is decided to become.
In the case of deformed bars, (1) 1.5 times the nominal diameter of the reinforcing bar, (2) 1.25 times the coarse aggregate maximum dimension, and (3) 25 mm. With such an interval, drilling is impossible, but usually the number of reinforcing bars is determined and arranged evenly by structural calculation. Therefore, if the hole diameter is reduced, the hoop and scallop bars embedded in the concrete can be drilled so as to dodge the reinforcing bars by searching for the reinforcing bars. Moreover, it is easier to drill holes so as to dodge the main bars embedded in the concrete. Further, if the drilling hole itself including the drilling hole diameter and depth becomes smaller, the labor required for drilling and the drilling time are greatly reduced.
The present invention can reduce the diameter of the hole without using an end holder having a significantly larger outer diameter than the hollow PC steel rod, and can increase the fixing force of the front end portion of the prestress force introducing device. It is an object of the present invention to provide a small-diameter-compatible prestress introduction device and an anchor structure thereof that can cope with the small-diameter described above.

In order to advantageously solve the above-described problem, in the prestress introducing device of the first invention, a pre-stressed PC steel material is disposed in the hollow PC steel bar and an anchor member is provided at the front end of the hollow PC steel bar. In the stress introducing device, the anchor member is a anchor member with a protrusion provided such that a protrusion is positioned on the front side in the axial direction of the hollow PC steel rod, and a rear end portion of the anchor member with the protrusion The male screw shaft portion is screwed into the female screw hole at the front end portion of the hollow PC steel rod, and the anchor member with a protrusion is integrally formed with the male screw shaft portion at a position away from the hollow PC steel rod. A large-diameter annular shaft portion having a diameter larger than the outer diameter of the hollow PC steel rod and a small-diameter shaft portion integrally provided with the large-diameter annular shaft portion of the anchor member with protrusions. Axial spacing Provided continuously alternately have, characterized in that projections by the large-diameter annular shaft portion is formed.
According to a second invention, in the prestress introduction device according to the first invention, a plurality of projections formed by a large-diameter annular shaft portion are provided at intervals in the axial direction of the anchor member with projections. And
In the third invention, in the prestress introducing device of the first invention or the second invention, the outer diameter of the projection formed by the large-diameter annular shaft portion is substantially the same as the outer diameter of the hollow PC steel rod of the first invention. Instead of this, the outer diameter of the hollow PC steel rod is set to be equal to or smaller than that.
The anchor structure of the prestress introduction device according to the fourth invention is characterized in that the anchor member with protrusions of the prestress introduction devices according to the first to third inventions is fixed so as to be embedded in non-shrink mortar or concrete.

According to the first invention, the male threaded shaft portion of the rear end portion of the anchor member with the protrusion provided so that the protrusion is located on the axially front side of the hollow PC steel rod in the prestress introducing device is the hollow Since it is screwed into the female screw hole at the front end of the PC steel bar, it is possible to fix the protruding anchor member and the filler at a position ahead of the front end of the hollow PC steel bar. The outer diameter of the member can be reduced, and a prestress introducing device that can cope with small-diameter drilling can be obtained. In addition, since the anchor member with a protrusion is used, it is possible to provide a prestress introduction device compatible with small-diameter drilling that can surely fix the filler and the like.
According to the second invention, since the anchor member with protrusions is provided with a plurality of protrusions at intervals in the axial direction, the stress can be distributed to the protrusions to transmit the stress, and the existing concrete Since transmission stress does not concentrate on one part of the structure, even if the existing concrete structure is a low-strength concrete structure, the stress is distributed without excessive stress concentration on the low-strength concrete structure It can be reduced and transmitted, and there is no fear that the existing concrete structure will be damaged, and reliable fixing can be achieved.
According to the third invention, since the outer diameter of the protrusion is equal to or smaller than the outer diameter dimension of the hollow PC steel rod, the hole diameter provided in the hollow existing concrete structure is made small and reliable with the existing concrete structure. Can be firmly established.
According to the fourth invention, since the anchor member with protrusions of the prestress introducing device is fixed so as to be embedded in non-shrink mortar or concrete, a simple anchor structure can be obtained and the number of protrusions can be reduced. It is easy to achieve a reliable locking effect.

    Next, the present invention will be described in detail based on the illustrated embodiment.

  1 and 2 show a small-diameter drilling-compatible prestress introduction device 8 according to an embodiment of the present invention. FIG. 1 (a) shows a small-diameter drilling-compatible prestress introduction device. A partially cutaway side view of one unit of the device 8 is shown, and (b) shows a longitudinal side view thereof. The male screw in the hollow PC steel rod 6 having the male screw portion 20 outside the one end portion (front end portion) in the longitudinal direction of the steel hollow PC steel rod body 6a and having the male screw portion 21 outside the other end portion (rear end portion). A female screw hole 22 at the front end of a bearing tube 25 having female screw holes 22 and 23 at both front and rear ends and a polygonal rotating tool engaging outer surface 24 is screwed to the part 21.

  A front male screw portion 27 of a stopper 26 made of a steel tubular annular locking piece is screwed into the female screw hole 23 at the rear end portion of the support tube 25, and a rotation is provided outside the rear end portion of the stopper 26. A moving tool engaging outer surface 28 is formed.

  The front end portion of the stopper 26 is disposed inside the support cylinder 25, and the rear end surface of the press locking piece 30 having the concave portion 29 is engaged with the front end portion, and the concave portion 29 of the front end portion of the press locking piece 30 is engaged. In the hollow PC steel rod 6, almost the whole other than the other end side is inserted and the other end side is arranged so as to protrude from the other end portion of the hollow PC steel rod 6. (Repulsive force PC steel rod for non-pull) 7 is fitted to the rear end portion.

  In this embodiment, the indentation steel bar 7 is constituted by a single indentation reaction force PC steel bar 7, but the other end side has a short removal reaction force PC steel bar and the indentation reaction force PC steel bar. The push-in reaction force PC steel rod 7 can be constituted by two pieces of the push-in reaction force PC steel rod slightly shorter than 7.

  A female screw hole 1 is provided inside the front end portion of the hollow PC steel rod 6, and a male screw shaft portion 3 at the rear end portion of the anchor member 2 with a protrusion is detachably screwed into the female screw hole 1, and the protrusion is attached. The anchor member 2 has a function of an end holder that supports the rear end portion of the reaction force PC steel rod 7 by the male screw shaft portion 3 at the rear end portion.

And in embodiment of this invention, the said anchor member 2 with a protrusion is larger diameter than the said external threaded shaft part 3 in the position away from the hollow PC steel rod 6, integrally with the said external threaded shaft part 3, A large-diameter annular shaft portion 4a having substantially the same diameter as the outer diameter of the hollow PC steel rod 6 and a small-diameter shaft portion 4b integrally connected to the large-diameter annular shaft portion 4a are axial directions of the protruding anchor member 2 Are alternately arranged at intervals. In this embodiment, the annular protrusion 4 is formed by the large-diameter annular shaft portion 4a.
The outer diameter dimension of the small-diameter shaft portion 4 b is set to be substantially the same as the outer diameter of the reaction force PC steel rod 7 and is made of the same material as that of the reaction force PC steel material 7.

  As shown in FIGS. 3 and 4, at least one protrusion 4 of the anchor member 2 with protrusions is required, and an existing concrete structure 9 side is provided via a filler 5 filled to embed the protrusions 4. Integration with is achieved. In the prestress introduction device 8a provided with the anchor member 2 with protrusions, the front end portion of the prestress introduction device 8a can be fixed by the anchor member 2 with protrusions alone and the hollow PC steel rod 6 can be fixed. In particular, it is not necessary to provide a conventional male screw on the outer periphery of the front end of the hollow PC steel rod 6.

  The annular protrusion 4 is preferably an annular protrusion 4 but may be an elliptical protrusion or a polygonal protrusion. The annular protrusions 4 are alternately and continuously provided with small-diameter shaft portions 4b that are integrally connected in the axial direction thereof, and the anchor member 2 with protrusions that includes three annular protrusions 4 and two small-diameter shaft portions 4b. It is said that. The outer diameter dimension of the anchor member 2 with protrusions is substantially the same as the outer diameter dimension of the hollow PC steel rod 6 and is smaller than the outer diameter dimension of the hollow PC steel rod 6.

  As described above, by setting the dimension smaller than the outer diameter dimension of the hollow PC steel bar 6, the anchor member 2 with the protrusion at the front end portion of the pre-stress introduction device 8 corresponding to the small-diameter drilling hole is placed in the existing concrete structure 9. The anchor hole 10 drilled in the existing concrete structure 9 can be made small. Further, since the anchor member 2 with the protrusion is provided with the annular protrusion 4, the fixing force between the outer peripheral side male screw portion of the front end portion and the filler of the conventional prestress introduction device 8 shown in FIG. The fixing force with the filler 5 per unit length in the axial direction can be greatly increased.

  In the above embodiment, the plurality of annular protrusions 4 are provided on the outer peripheral surface of the front end portion of the hollow PC steel rod 6 at intervals in the axial direction, so that the fixing force is distributed to the plurality of annular protrusions 4. Can be distributed and transmitted to the existing concrete structure through the fixing force of the annular projections dispersed in a plurality, and the burden stress of the existing concrete structure can be reduced in the axial direction of the anchor member 2 with projections. .

  When a plurality of protrusions 4 are provided at intervals in the axial direction, the outer diameter of each protrusion 4 may be different, and the fixing force of each protrusion 4 may be controlled. For example, the outer diameter of each protrusion 4 may gradually increase from small, medium, and large toward the front part from the rear part (base end side) of the anchor member 2 with protrusions. Even when the outer diameter is increased, the outer diameter may be substantially the same as the outer diameter of the hollow PC steel rod 6. Within the width dimension in the axial direction, the protrusion 4 presses outward in the radial direction as a frustoconical outer peripheral surface (tapered shape) whose diameter gradually increases from the rear side toward the front side. Such a wedge effect may be provided, and adhesion to concrete may be enhanced by using the circumferential outer peripheral surface, the axial front surface and the rear surface as rough surfaces.

  As shown in FIG. 3, a plurality of large-diameter annular grooves 11 are provided in the small-diameter anchor hole 10 formed in the concrete structure 9 such as the existing concrete structure 9 at intervals in the axial direction. In this case, it is possible to increase the fixing strength with the anchor member 2 with the protrusion at the front end portion of the pre-stress introduction device 8 for small-diameter drilling.

  Specifically, as shown in FIG. 3, the inner peripheral surface of the small-diameter anchor hole 10 is uniformly cut in the circumferential direction, and a large-diameter annular groove 11 is formed concentrically with the small-diameter anchor hole 10 in the axial direction of the small-diameter anchor hole. The anchor hole 13 with a large-diameter annular locking groove portion provided with a plurality of large-diameter annular locking groove portions 12 provided at intervals may be formed. The small-diameter anchor hole 10 is connected to the small-diameter anchor hole 10 and is concentric with the small-diameter anchor hole 10 and expands toward the distal end side in the small-diameter anchor hole 10 axial direction. A frustoconical grooved anchor hole provided with a frustoconical groove may be used.

  Since the large-diameter annular locking groove 11 continuous to the entire circumference of the small-diameter anchor hole 10 is provided, the adhesion strength between the filler 5 and the large-diameter annular locking groove portion can be increased. Since there is no directionality in the circumferential locking effect formed by the large-diameter annular locking groove 11 formed on the entire circumference, the prestressing force can be increased and fixed using the locking effect on the entire circumference, and Since the fixing portion on the front end side of the prestress force introduction device 8 is disposed so as to be located in the region of the large-diameter annular locking groove 12 in the anchor hole axial direction or the region deeper than the large-diameter annular locking groove 12. The front end side of the prestress force introducing device 8 can be reliably fixed, the prestress force of the prestress force introducing device 8 per one can be increased, and the total number used can be reduced. Further, the structure of the anchor hole 13 with the large-diameter annular locking groove is also a simple structure, so that the fixing structure can be made simple.

  A new concrete structure 14 that is constructed adjacent to the existing concrete structure 9, a cast-in-place concrete structure, a precast concrete structure, or a precast concrete structure may be used. The pre-stress introduction device 8 corresponding to the small diameter of the present invention is arranged in advance by providing a through hole, a horizontal hole or an upward opening groove, and the existing concrete structure 9 and the new concrete What is necessary is just to fill the filler 5 such as non-shrink mortar over the holes or grooves of the structure 14. Reference numeral 40 denotes a delayed-curing type adhesive / rust preventive material which is cured after the filler 5 is cured, and is integrated with the hollow PC steel rod 6 and the reaction force PC steel rod 7 to improve the ultimate strength. It is.

  In the state shown in FIG. 1, for example, the prestress introduction device 8 for small-diameter drilling is omitted, but the front frame and the rear frame are coupled in parallel by a plurality of connecting rods, and the rear frame It is placed in a frame-shaped frame with a hydraulic jack on the side, and is pressed by a push-in steel rod that is engaged with the tip of the movable piston and inserted into the central hollow portion of the stopper 26 using a hydraulic jack. After pressing the stop 30 so as to move toward the hollow PC steel rod 6 and introducing a compressive force so as to push the pushing reaction force PC steel rod 7 into the hollow PC steel rod 6, in that state The free support cylinder 25 or the stopper 26 is rotated in the direction approaching the pressing locking piece 30 to move the stopper 26 forward, and the front end portion of the stopper 26 is pushed and locked. 30 to engage a diagram showing a state of being separated from the frame-shaped frame. The stopper 26 or the support tube 25 is rotated by a rotating tool to press the reaction force PC steel rod 7 so as to compress the hollow PC steel rod 6, or the stopper 26 or the support tube 25 is moved. The prestress may be introduced into the concrete structure through the hollow PC steel bar 6 by rotating the reverse direction to release the compressive force of the reaction force PC steel bar 7.

The structure of the rear end portion of the pre-stress introduction device 8 for small-diameter drilling is known from Japanese Patent Application Laid-Open No. 2001-207590 and the like, and various types of reaction machines including push-in reaction force PC steel bars and hollow PC steel bars. A device of the form can also be used.
The prestress introduction device 8 for small diameter of the present invention is also newly installed after the filler 5 is cured and the anchor member 37 and the anchor member 2 with protrusions are embedded and fixed, and then the prestress introduction device 8 is opened. The concrete structure 14 and the existing concrete structure 9 act so as to make the concrete structures approach each other through the filler 5 in the direction in which the anchor member 2 with protrusions and the anchor member 37 approach, and the hollow PC in a tension state The shortening of the steel rod 6 is prevented by adhesion with the filler 5.

  In addition, the prestress introduction device 8 for small-diameter drilling according to the present invention can be applied to a new concrete structure 14 or a tensile force in addition to the connection between the existing concrete structure 9 and the new concrete structure 14. The use form similar to the pre-stress introduction apparatus provided with the existing hollow PC steel rod 6 is also used, such as being used for the purpose of canceling the tensile force at the location generated at the end of the concrete member.

  As a material of the anchor member 2 with projections, PC steel material may be used. In addition, you may make it use the prestress introduction apparatus 8 of this invention for holes other than a small diameter drilling hole.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a pre-stress introduction device for small-diameter drilling according to the present invention, in which (a) is a front view and (b) a longitudinal side view. It is a perspective view which shows the anchor member with a protrusion of the front end side used for the pre-stress introduction apparatus of the small-diameter drilling type of this invention. The anchor member with protrusions in the pre-stress introduction device for small-diameter drilling of the present invention is arranged in a large-diameter annular groove hole drilled in an existing concrete structure, and prestress is introduced between the concrete structures. It is a partially vertical side view which shows the state just before integrating. The anchor member with protrusions in the pre-stress introduction device for small-diameter drilling of the present invention is arranged in a hole drilled in an existing concrete structure, and immediately before the pre-stress is integrated and integrated with the concrete structure. It is a partially vertical side view which shows a state. The conventional prestress introduction apparatus is shown, Comprising: (a) is a front view, (b) It is a vertical side view. FIG. 6 is a partially longitudinal side view showing a state immediately before a tip portion of a conventional prestress introduction device is placed in a hole cut in an existing concrete structure and prestressed between the concrete structures and integrated. . It is a vertical side view which shows the other form of the front-end | tip part in the conventional prestress introduction apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Female thread hole 2 Anchor member with protrusion 3 Male threaded shaft part 4 Protrusion 4a Large diameter annular shaft part 4b Small diameter shaft part 5 Filler 6 Hollow PC steel rod body 6a Hollow PC steel rod body 7 Pushing reaction force PC steel rod 8 Small diameter cutting Prestress introduction device 8a corresponding to hole Prestress introduction device 9 Existing concrete structure 10 Large-diameter annular groove 11 Large-diameter annular groove 12 Large-diameter annular locking groove 13 Anchor hole 14 with large-diameter annular locking groove Concrete structure 20 Male threaded portion 21 Male threaded portion 22 Female threaded hole 23 Female threaded hole 24 Rotating tool engaging outer surface 25 Bearing cylinder 26 Stopper 27 Front male threaded portion 28 Rotating tool engaging outer surface 29 Recess 30 Press locking piece 31 Female threaded portion 32 Anchor material 37 Anchor material 40 Adhesive rust preventive material 41 Male screw member 42 Anchor nut (supporting member)

Claims (4)

In the prestress introduction device in which the reaction force PC steel material is disposed in the hollow PC steel rod and the anchor member is provided at the front end portion of the hollow PC steel rod, the anchor member has an axial front portion thereof rather than the hollow PC steel rod. A protruding anchor member provided so that the protrusion is located on the side is used, and the male screw shaft portion of the rear end portion of the protruding anchor member is screwed into the female screw hole of the front end portion of the hollow PC steel rod , The anchor member with a protrusion is integrally formed with the male threaded shaft portion, and is a large-diameter annular member having a larger diameter than the male threaded shaft portion at a position away from the hollow PC steel rod and substantially the same diameter as the outer diameter of the hollow PC steel rod. Shafts and small-diameter shafts that are integrally connected to the large-diameter annular shaft are alternately arranged at intervals in the axial direction of the anchor member with projections, and the projections are formed by the large-diameter annular shafts. and characterized in that it is formed That pre-stress introduction device. The prestress introducing device according to claim 1, wherein a plurality of protrusions formed by the large-diameter annular shaft portion are provided at intervals in the axial direction of the anchor member with protrusions. The outer diameter of the projection formed by the large-diameter annular shaft portion is set to be equal to or smaller than the outer diameter of the hollow PC steel rod instead of the outer diameter of the hollow PC steel rod of claim 1. The prestress introduction device according to claim 1 or 2. Anchor structure prestressing introduction apparatus characterized by securing to bury the projecting anchored members of the prestress introduced according to non-shrink mortar or concrete to any one of claims 1 to 3.

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