JP2014005634A - Anchor re-tensioning system and anchor re-tensioning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anchor re-tensioning system and an anchor re-tensioning method for easily mounting a coupler without being affected by any foreign matter adhered to an anchor head.SOLUTION: A re-tensioning anchor system for re-tensioning an anchor installed underground includes: an anchor head formed with a circumferential groove on a side face at the end of the anchor; and a coupler having a cylindrically structured body section and an engagement section which is engaged with the anchor head in the inner periphery of the bottom of the body section at the anchor side. The coupler is configured so as to be separated into two semi-cylindrical pieces, and when the semi-cylindrical pieces are fitted into each other, each of the engagement sections of the semi-cylindrical pieces is engaged with the circumferential groove of the anchor head.

Description

  The present invention relates to an anchor re-tension system and an anchor re-tension method for re-tensioning an anchor placed in the ground.

  Conventionally, a ground anchor (hereinafter also referred to as an anchor) is placed in the ground, and by applying tension, the slope is stabilized, the retaining wall is reinforced, the reaction force of the suspended structure, and the permanent structure is stabilized. Ground anchor technology has been proposed. However, since the tension of the anchor may decrease due to terrain change or aging deterioration, it may be necessary to re-tension the anchor.

  The re-tensioning of the anchor is performed by grasping and pulling the end of the tensile material protruding from the anchor head with a jack. At this time, the length of the end of the tensile material may be insufficient, and the end of the tensile material cannot be gripped by the jack, making it difficult to pull by the jack, and re-tensioning may not be possible. It was.

  In recent years, Patent Document 1 proposes a technique related to an anchor re-tensioning system. Patent Document 1 discloses a structure in which a screw structure is provided on the outer peripheral surface of the anchor head, and the male cap structure of the anchor head and an oil cap having a female screw structure on the inner peripheral surface are screwed together. An anchor re-tensioning system is disclosed in which a predetermined tension force is applied by screwing a female screw of a jack to the anchor head and pulling a tension member together with the anchor head to re-tension.

  Further, in an anchor re-tensioning system for re-tensioning a ground anchor placed in the ground, a coupler having a female screw structure on the inner periphery is connected to an anchor head having a screw structure on the side surface of the main body. A product technology is disclosed in which re-tensioning is performed by screwing and screwing so as to cover, and pulling a tension bar screwed to the coupler with a jack.

  As shown in FIG. 1, the anchor re-tensioning system 10 according to the product technology includes a tension member 11, an anchor 12, an anchor plate 13, a tension bar 14, a jack 15, a lock nut 16, an anchor head 20, and a coupler 30.

  As shown in FIGS. 2A and 2B, the anchor head 20 includes, for example, two tapered holes 21 at the center, a counterbore portion 23 at the lowermost portion of the tapered hole 21, and a circumference of the side surface portion. A male screw structure 22 is provided. As shown in FIGS. 3A to 3C, the coupler 30 includes a hole of a female screw structure 32 on the upper surface portion and a female screw structure 31 that is threaded along the inner periphery of the bottom surface portion. In addition, the taper hole 21 is provided in the same number as the number of tensile materials of the anchor, and each tensile material is inserted.

  When the user re-tensions the anchor 12, the anchor head 20 is exposed as shown in FIG. Next, the user aligns the coupler 30 with respect to the anchor head 20 as shown in FIG. 4 (a), and screwes them together as shown in FIGS. 4 (b) and 6 (b). . Further, the user screws the tension bar 14 having a male screw structure into the upper female screw structure 32 of the screwed coupler 30 as shown in FIG. Thereafter, the user pulls the tension bar 14 with the jack 15 and applies a predetermined tension to the tension member 11. The screwing surface 33 of the anchor head 20 and the coupler 30 is a surface in the pulling direction A at the screwing portion as shown in FIG. Subsequently, the tension head is lifted by unloading the traction force by filling the space between the anchor head 20 and the anchor plate 13 lifted with shims.

Japanese Patent Laid-Open No. 7-224423

  However, the invention described in Patent Document 1 and the above-described product technology tend to cause foreign matter to adhere to the anchor head and deformation / breakage of the screwed portion, causing problems when attaching the coupler to the anchor head. There was a thing.

  Also, since the coupler is very heavy, it takes a lot of labor for the user to lift the coupler and screw it onto the anchor head.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide an anchor re-tensioning system and an anchor re-tensioning method that make it easy to mount a coupler without being affected by foreign matter adhering to the anchor head. .

  An anchor re-tensioning system according to the present invention is an anchor re-tensioning system for re-tensioning an anchor placed in the ground. An anchor head at an end of an anchor and provided with a circumferential groove on a side surface; And a coupler having an engagement portion that engages with the anchor head on the inner periphery of the bottom of the main body portion on the anchor side, and the coupler is separated into two half cylinder pieces, By engaging the pieces, each of the engaging portions of the half cylinder pieces is engaged with the circumferential groove of the anchor head.

  In the anchor head of the present invention, the surface of the circumferential groove in the pulling direction of the engaging portion is a surface orthogonal to the axial direction of the anchor, and in the direction opposite to the pulling direction of the engaging portion, The surface of the circumferential groove may have a reverse taper shape with respect to the anchor.

  The coupler according to the present invention includes at least one positioning pin and a positioning pin receiving hole in each half cylinder piece, and inserts and fits the positioning pin in one half cylinder piece and the positioning pin receiving hole in the other half cylinder piece. It may be a thing.

  The coupler of the present invention has an inner nut joint portion on the inner periphery of the lid portion opposite to the anchor side of the main body portion, includes an inner nut fitted to the inner nut joint portion, and has a female screw structure on the inner periphery of the inner nut. You may prepare.

  The anchor re-tensioning system according to the present invention further includes a tension bar having a screw structure at the end on the coupler side, screwed into the female thread structure of the coupler, and a jack installed around the tension bar. It may be.

  The anchor re-tensioning method according to the present invention includes an anchor head provided at an end of an anchor placed in the ground and provided with a circumferential groove on a side surface, a main body portion of a cylindrical structure, and an anchor side of the main body portion. An anchor re-tensioning system having an engagement portion that engages with the anchor head on the inner periphery of the bottom portion, and a coupler that separates into two half-tube pieces, each of the engagement portions of the separated half-tube pieces, A step of engaging and fitting with the circumferential groove of the anchor head, a step of screwing the tension bar into the female thread structure of the coupler, a step of installing a jack so as to surround the tension bar, and a lock nut on the tension bar The step of fixing the tension bar and jack by screwing and the step of pulling the tension bar by jack and the gap between the pulled anchor head and the shim By inserting, in which a step of re-tensioning the anchor.

  The anchor re-tensioning method of the present invention may include a step of joining an inner nut having a female screw structure on the inner periphery to the coupler.

  An anchor re-tensioning system according to the present invention includes an anchor head at an end portion of an anchor and provided with a circumferential groove on a side surface thereof, and a main body portion of a cylindrical structure and an anchor head on an anchor side bottom of the main body portion. And a coupler that separates into two half-cylinder pieces, the half-cylinder pieces of the separated couplers are fitted together, and the engagement parts of the half-cylinder pieces are respectively connected to the circumferential grooves of the anchor head. By engaging with the anchor head, it is possible to provide an anchor re-tensioning system that makes it possible to easily mount a coupler even if foreign matter adheres to the anchor head and reduce the labor of mounting the coupler.

  The anchor re-tensioning method of the present invention includes a step of engaging and engaging each of the engaging portions of the separated half cylinder pieces with the circumferential groove of the anchor head, and screwing the tension bar into the internal thread structure of the coupler. A step, a step of installing a jack so as to surround the tension bar, a step of fixing the tension bar and the jack by screwing a locking nut to the tension bar, a step of pulling the tension bar by the jack, The step of re-tensioning the anchor by inserting a shim into the gap between the anchor heads made possible makes it possible to easily attach the coupler even if foreign matter adheres to the anchor head. It is possible to provide an anchor re-tensioning method with reduced labor.

It is sectional drawing seen from the side of the anchor re-tensioning system which concerns on the conventional product technology. (A) It is a top view of the anchor head based on the conventional product technology. (B) It is sectional drawing seen from the side surface of the anchor head which concerns on the conventional product technology. (A) It is a top view of the coupler based on the conventional product technology. (B) It is sectional drawing seen from the side surface of the coupler which concerns on the conventional product technology. (C) It is a bottom view of the coupler based on the conventional product technology. (A) It is a figure for demonstrating the screwing procedure of the anchor head and coupler which concerns on the conventional product technology. (B) It is a figure for demonstrating the screwing site | part of the anchor head and coupler which concerns on the conventional product technology. It is a figure for demonstrating the screwing surface of the anchor head and coupler which concerns on the conventional product technology. It is a figure for demonstrating a part of procedure of the anchor re-tensioning method which concerns on the conventional product technology. It is sectional drawing seen from the side of the anchor re-tensioning system which concerns on embodiment of this invention. (A) It is a top view of the anchor head concerning the embodiment of the present invention. (B) It is sectional drawing seen from the side surface of the anchor head in embodiment of this invention. It is a perspective view of a coupler concerning an embodiment of the present invention. (A) It is a top view of the half cylinder piece which concerns on embodiment of this invention. (B) It is a side view of the half cylinder piece concerning the embodiment of the present invention. (C) It is a bottom view of the half cylinder piece which concerns on embodiment of this invention. (D) It is a top view of the inner nut which concerns on embodiment of this invention. (E) It is sectional drawing of the inner nut which concerns on embodiment of this invention. (A) It is a top view of the half cylinder piece which concerns on embodiment of this invention. (B) It is a side view of the half cylinder piece concerning the embodiment of the present invention. (C) It is a bottom view of the half cylinder piece which concerns on embodiment of this invention. It is the flowchart which showed the processing flow of the anchor re-tensioning method which concerns on embodiment of this invention. It is a figure for demonstrating the procedure before the anchor head and coupler engagement in the anchor re-tensioning method which concerns on embodiment of this invention. It is a figure for demonstrating the engagement procedure of the anchor head and coupler which concerns on embodiment of this invention. It is a figure for demonstrating the engaging part of the anchor head which concerns on embodiment of this invention, and a coupler. It is a figure for demonstrating the engagement surface of the anchor head and coupler which concerns on embodiment of this invention. It is a figure for demonstrating the procedure after engagement of the anchor head and coupler which concern on embodiment of this invention.

  An anchor re-tensioning system according to an embodiment of the present invention will be described in detail below based on a preferred embodiment shown in the accompanying drawings.

  An anchor re-tensioning system according to an embodiment of the present invention re-tensions an anchor placed in the ground, and includes an anchor head at an end of the anchor and provided with a circumferential groove on a side surface thereof. And a coupler having an engagement portion that engages with the anchor head on the inner periphery of the bottom of the main body portion on the anchor side of the main body portion, and the coupler is separated into two half cylinder pieces, By fitting the half cylinder pieces, the engaging portions of the half cylinder pieces are engaged with the circumferential grooves of the anchor head.

  An anchor re-tensioning system according to an embodiment of the present invention further includes a tension structure that includes a screw structure at an end portion on the coupler side and is screwed into the female thread structure of the coupler, and a jack that is installed around the tension bar. It has.

  As shown in FIG. 7, the anchor re-tensioning system 40 according to the embodiment of the present invention includes an anchor 42, an anchor plate 43, a tension bar 44, a jack 45, a set nut 46, and a coupler 60.

  The anchor 42 is driven substantially perpendicular to the ground surface, has a cylindrical shape, includes a tension member 41 and an anchor head 50, and stabilizes the periphery of the placement point by the tension force of the inner tension member 41. Reinforcing, etc.

  The tension member 41 is a stranded wire of PC steel located at a substantially central portion in the cylindrical shape of the anchor 42, and imparts tension to the anchor 42.

  The anchor plate 43 is a bearing plate that is installed substantially horizontally with respect to the ground surface. The anchor member 50 penetrates the substantially central portion of the anchor plate 43 and is fastened to the end portion of the tensile member 41. It is crimped and transmits the tension force of the anchor 42 toward the ground surface to the ground surface.

  As shown in FIGS. 8A and 8B, the anchor head 50 has a disk shape, and in the present embodiment, two tapered holes 51 and a circumferential groove 52 provided on the side surface are provided at the center of the upper surface. Is provided. The anchor head 50 is pressed against the ground surface via the anchor plate 43 by the tension of the tension member 41. The tapered hole 51 is a tapered hole cut from the upper part of the anchor head 50 toward the lower part, and a wedge (not shown) that passes through the tension member 41 and fits into the tapered shape is inserted from the upper part of the tapered hole 51. The tension member 41 is fastened to the anchor head 50 by fitting. Note that the taper hole 51 may be provided with a small number or a large number according to the number of the tension members 41 penetrating therethrough. A rust preventive material may be applied to the taper hole 51. The counterbore 53 is a conical hole that is cut through and has a diameter larger than the narrowest part of the tapered hole 51 in a conical shape.

  The anchor head 50 is a surface in which the surface of the circumferential groove 52 (engagement surface 52a) is orthogonal to the axial direction of the anchor 42 in the pulling direction A (see FIG. 5) of the engagement portion with the coupler 60 described later. The surface 52 (tapered surface 52c) of the circumferential groove in the direction opposite to the pulling direction A of the engaging portion is reversely tapered with respect to the axial direction of the anchor 42, that is, tapered in the direction of the pulling direction A. It is.

  The circumferential groove 52 is provided along the outer periphery of the side surface of the anchor head 50, and includes an engagement surface 52a, a parallel surface 52b, and a tapered surface 52c from the pulling direction A of the engagement portion, and is engaged with the engagement portion of the coupler 60. Match. The engagement surface 52a is a surface orthogonal to the axial direction of the anchor 42, is engaged with the engagement portion of the coupler 60, and when the coupler 60 described later is pulled in the pulling direction A, the pulling force is applied to the anchor head 50. It is the part that is transmitted to. The parallel surface 52b is parallel to the axial direction of the anchor 42, and is fitted and engaged with the engaging portion of the coupler 60, and determines the position where the coupler 60 is engaged. The tapered surface 52c has a tapered shape with respect to the pulling direction A, and guides the engaging portion of the coupler 60 to the parallel surface 52b that is the engaging position when the anchor head 50 engages with the coupler 60.

  The coupler 60 is shown as in FIG. 9, and has a cylindrical structure main body 60a, an inner nut joint 60b on the inner periphery of the lid opposite to the anchor 42 side of the main body 60a, and an anchor 42 side of the main body 60a. An engagement portion 60c is provided on the inner periphery of the bottom portion, and engages so as to cover the anchor head 50 from the pulling direction A side. The inner nut joint 60b has an annular shape and includes an inner nut 61 joined to the lower surface. The engaging part 60c has an annular shape and is located at the bottom of the inner peripheral surface of the main body part 60a. The difference between the outer peripheral radius and the inner peripheral radius is relative to the depth of the circumferential groove 52 in the inner peripheral direction. It is long and the axial width of the anchor 42 is equal to or smaller than the axial width of the anchor 42 of the parallel surface 52b of the circumferential groove 52, and is substantially equal or thin, and fits into the circumferential groove 52. The tension bar 44 is screwed onto the lid portion of the coupler 60, and the traction force is relayed from the anchor head 50 to the tension bar 44.

  The coupler 60 is obtained by fitting two half-cylinder pieces, and the engagement portion 60 c is engaged with the circumferential groove 52 of the anchor head 50 by fitting the two half-cylinder pieces. Fig.10 (a) shows the top view of one half cylinder piece 65a, and FIG.10 (b) shows the side view of the half cylinder piece 65a. FIG. 10C shows a bottom view of the half cylinder piece 65a, FIG. 10D shows a top view of the inner nut 61, and FIG. 10E shows the inner nut 61. FIG. Further, FIG. 11 (a) shows a top view of the other half cylinder piece 65b, FIG. 11 (b) shows a side view of the half cylinder piece 65b, and FIG. The bottom view of the half cylinder piece 65b is shown.

  FIG. 14 illustrates the procedure for engaging the anchor head 50 with the coupler 60. The coupler 60 is composed of a half cylinder piece 65 a and a half cylinder piece 65 b, and is disposed on the anchor head 50. Specifically, the coupler 60 is fitted into the circumferential groove 52 of the anchor head 50 so that the engagement portions 60c of the half cylinder piece 65a and the half cylinder piece 65b are engaged, as shown in FIG. is there. At that time, the half cylinder piece 65a and the half cylinder piece 65b are fitted so that the positioning pin 71a fits into the positioning pin receiving hole 69b and the positioning pin 71b fits into the positioning pin receiving hole 69a, while the engaging portion 60c. Are fitted so as to cover the parallel surface 52b of the circumferential groove 52.

  That is, the coupler is provided with at least one positioning pin and positioning pin receiving hole in each of the two half cylinder pieces, and the positioning pin in one half cylinder piece and the positioning pin receiving hole in the other half cylinder piece are inserted and joined. To do.

  The half cylinder piece 65a has a shape obtained by dividing the coupler 60 into two vertically from the side surface, and includes a positioning pin receiving hole 69a at the center of one side joint surface and a positioning pin 71a at the center of the other side joint surface. . The positioning pin receiving hole 69a is a hole into which the positioning pin 71b provided in the half cylinder piece 65b is inserted, and is a perforated cylindrical hole. The positioning pin 71a is a cylindrical pin having a diameter slightly smaller than the hole diameter of the positioning pin receiving hole 69a, and a portion protruding from the joint surface is inserted into the positioning pin receiving hole 69b of the half cylinder piece 65b so as to be semi-fitted. The joining position of the cylinder piece 65a and the half cylinder piece 65b is determined.

  The semi-cylindrical piece 65a includes two counterbore 67a drilled in a direction perpendicular to the one side joint surface from the outer peripheral surface, and two joint holes 68a on the other side joint surface. The counterbore 67a is a through-hole through which a bolt that is screwed into the joint hole 68b provided in the half cylinder piece 65b is inserted. The joint hole 68a is a threaded hole for screwing a bolt inserted through the counterbore 67b of the half cylinder piece 65b. The counterbore 67a and the joining hole 68a solidify the half cylinder piece 65a and the half cylinder piece 65b with bolts.

  The coupler 60 has an inner nut joint portion 60b on the inner periphery of the lid portion opposite to the anchor 42 side of the main body portion 60a, and includes an inner nut 61 joined to the inner nut joint portion 60b. A screw structure 62 is provided.

  The half cylinder piece 65a includes an inner nut 61 inside the upper surface and a bolt hole 63 on the upper surface. The inner nut 61 has an annular shape, is provided with a bolt receiving hole 64 on the upper surface, is provided with a female screw structure 62 on the inner periphery of the annular shape, and is screwed with a male screw structure below the tension bar 44. The bolt hole 63 is a through hole through which a bolt 66 screwed into a bolt receiving hole 64 provided in the inner nut 61 is inserted. The bolt receiving hole 64 is a threaded hole into which the bolt 66 inserted through the bolt hole 63 is screwed. The bolt hole 63 and the bolt receiving hole 64 join the inner nut 61 to the half cylinder piece 65 a by screwing the bolt 66 inserted through the bolt hole 63 into the bolt receiving hole 64.

  The half cylinder piece 65b has a shape in which the coupler 60 is divided into two in the vertical direction from the side surface, and includes a positioning pin receiving hole 69b at the center of one side joint surface and a positioning pin 71b at the center of the other side joint surface. . The positioning pin receiving hole 69b is a hole into which the positioning pin 71a is inserted and is a perforated cylindrical hole. The positioning pin 71b is a cylindrical pin having a diameter slightly smaller than the diameter of the positioning pin receiving hole 69b, and a portion protruding from the joint surface is inserted into the positioning pin receiving hole 69a of the half cylinder piece 65a so as to be semi-fitted. The joining position of the cylinder piece 65b and the half cylinder piece 65a is determined.

  The half cylinder piece 65b is provided with two counterbore 67b drilled in a direction perpendicular to the one side joint surface from the outer peripheral surface, and two joint holes 68b on the other side joint surface. The counterbore 67b is a through-hole through which a bolt that is screwed into the joint hole 68a provided in the half cylinder piece 65a is inserted. The joint hole 68b is a threaded hole for screwing a bolt inserted through the counterbore 67a of the half cylinder piece 65a. The counterbore 67b and the joining hole 68b solidify the half cylinder piece 65b and the half cylinder piece 65a with bolts. The half cylinder piece 65b is the same as the half cylinder piece 65a except that the bolt hole 63 for joining the inner nut 61 does not exist and the inner nut 61 is not joined.

  The tension bar 44 has a cylindrical shape and is screwed substantially perpendicularly to the ground surface into a female screw structure 62 provided in an inner nut 61 joined to the coupler 60 by a male screw structure provided at an end portion on the coupler 60 side. And is connected to the jack 45 by a lock nut 46 screwed to the male screw structure provided on the opposite end to be screwed with the coupler 60, and transmits the traction force applied from the jack 45 to the coupler 60. It is.

  The jack 45 surrounds the tension bar 44 on the anchor plate 43 and is arranged substantially perpendicular to the ground surface. The jack 45 is connected to the tension bar 44 by a lock nut 46 to give a traction force to the tension bar 44. The tension member 41 is pulled in the opposite direction with respect to the ground surface via the coupler 60 and the anchor head 50 connected to the tension bar 44. The lock nut 46 is screwed into the male screw structure at the protruding portion of the tension bar 44 protruding from the jack 45, and connects the jack 45 and the tension bar 44 to transmit the traction force of the jack 45 to the tension bar 44. Is.

  The procedure until re-tensioning the anchor 42 in the embodiment of the present invention includes an anchor head 50 having an end portion of the anchor 42 and a circumferential groove 52 provided on a side surface, a main body portion of a cylindrical structure, and An anchor re-tensioning system 40 having an engagement portion 60c that engages with the anchor head 50 and a coupler 60 that separates into two half-tube pieces is provided on the inner periphery of the bottom portion of the main body on the anchor 42 side. The engagement portion 60c of the half cylinder piece 65a and the half cylinder piece 65b is engaged with the circumferential groove 52 of the anchor head 50, and the tension bar 44 is screwed into the female screw structure of the coupler 60. A step, a step of installing a jack 45 so as to surround the tension bar 44, and a screw nut 46 to the tension bar 44 to screw the tension bar 44 Fixing the jack 45; pulling the tension bar 44 by the jack 45; and re-tensioning the anchor 42 by inserting a shim into the gap of the pulled anchor head 50. Is. In addition, the anchor re-tensioning system 40 may have a step of joining the inner nut 61 including the female thread structure 62 on the inner periphery to the coupler 60 in advance.

  A procedure until the anchor 42 is re-tensioned in the embodiment of the present invention will be described with reference to the steps of the flowchart of FIG. Moreover, when explaining along the said step, each structure of the anchor re-tension system 40 is demonstrated in detail using FIG. 13 thru | or FIG.

  FIG. 12 is a chart showing a processing flow of the anchor re-tensioning method according to the embodiment of the present invention. FIG. 13 is a view for explaining a procedure until the coupler 60 and the tension bar 44 are engaged with the anchor head 50. FIG. 14 is a diagram for explaining a procedure of engagement between the anchor head 50 and the coupler 60. FIG. 15 is a view for explaining an engagement portion between the anchor head 50 and the coupler 60. FIG. 16 is a view for explaining the engagement surfaces of the anchor head 50 and the coupler 60. FIG. 17 is a view for explaining a procedure after the anchor head 50, the coupler 60, and the tension bar 44 are engaged in the procedure of the anchor re-tensioning method according to the embodiment of the present invention.

  Before re-tensioning the anchor 42, the user removes the protection portion at the end of the ground surface of the anchor 42 that has been placed in the ground, and exposes the anchor head 50 as shown in FIG. At this time, since there is a possibility that foreign matters are attached to the anchor head 50, they are removed. Since the circumferential groove 52 in the anchor head 50 is a part that engages with the coupler 60, foreign matter is removed intensively.

  First, the user engages the engaging portion 60c of the coupler 60 with the circumferential groove 52 of the anchor head 50 as shown in FIGS. 13B and 15 (step 1).

  Specifically, the user arranges the inner nut 61 inside the upper surface of the half-cylinder piece 65a, inserts the bolt 66 into the bolt hole 63 of the half-cylinder piece 65a, and inserts the bolt hole into the bolt receiving hole 64 of the inner nut 61. The bolt 66 inserted through 63 is screwed, and the inner nut 61 is joined to the half cylinder piece 65a. The inner nut 61 may be joined to the half cylinder piece 65a in advance.

  As shown in FIGS. 14 and 15, the user lifts the half cylinder piece 65 a and the half cylinder piece 65 b constituting the coupler 60 and places them on the anchor head 50. The half cylinder piece 65a and the half cylinder piece 65b are sandwiched so as to engage with the circumferential groove 52 of the anchor head 50. At that time, the user joins the half cylinder piece 65a and the half cylinder piece 65b so that the positioning pin 71a is fitted into the positioning pin receiving hole 69b and the positioning pin 71b is fitted into the positioning pin receiving hole 69a. The mating part 60c is fitted so as to cover the parallel surface 52b in the circumferential groove 52. Even when the position of the engaging portion 60c is shifted downward due to the weight, the user slides upward by the tapered surface 52c, so that it is easily corrected to the position of the parallel surface 52b that is the engaging position. it can.

  The user inserts a bolt through the counterbore 67a in the half tube piece 65a and the half tube piece 65b that are fitted together, and screws into the joint hole 68b, while inserting the bolt through the counterbore 67b and into the joint hole 68a. Screw together. Thereby, the fitting of the half cylinder piece 65a and the half cylinder piece 65b and the engagement between the coupler 60 and the anchor head 50 are completed.

  The user needs to attach the coupler 60 because the half cylinder piece 65a and the half cylinder piece 65b, which are approximately half of the total weight of the coupler 60, are fitted to the anchor head 50 so as to be fitted. Compared to attaching the entire 60 at once. In addition, since the engagement surface 52a is a disk-like flat surface and the coupler 60 is mounted, the contamination is less likely to be mixed in and foreign matter contamination and distortion can be easily corrected.

  Next, the user lifts the tension bar 44 to the upper part of the coupler 60 and arranges the tension bar 44 substantially perpendicularly to the upper surface of the coupler 60, and the lower end male thread structure of the tension bar 44 is inserted into the hole of the inner nut joint 60 b of the coupler 60. On the other hand, alignment is performed to a position where insertion can be performed. As shown in FIGS. 13C and 16, the user inserts the tension bar 44 into the hole of the inner nut joint portion 60 b and rotates it with respect to the internal thread structure 62 provided in the inner nut 61 inside the coupler 60. The male thread structure of the tension bar 44 is screwed into the female thread structure 62 of the inner nut 61 (step 2).

  The user installs the jack 45 around the tension bar 44. The user adjusts the position of the jack 45 so that the tension bar 44 is positioned in the center of the jack 45 (step 3).

  As shown in FIGS. 17A and 17B, the user inserts the locking nut 46 from the upper end of the tension bar 44 protruding from the jack 45, and screws it into the tension bar 44, so that the jack 45 and the tension bar 44 are inserted. And fix. The jack 45 may be a hydraulic jack, and may be an air jack or another type jack (step 4).

  The user applies a predetermined pulling force to the jack 45 and pulls up the tension bar 44 in the pulling direction A (see FIG. 17C). Accordingly, the user pulls up the coupler 60 screwed to the tension bar 44 in the pulling direction A, and transmits the pulling force to the anchor head 50 through the engaging portion 60c of the coupler 60 and the engaging surface 52a of the anchor head 50. The engaging surface 52a has a simple structure and is robust even when a traction force is applied and a foreign substance or the like is mixed, so that there is little possibility of further distortion. By pulling the anchor head 50, the user lifts the anchor head 50 from the anchor plate 43, and applies a predetermined tension force to the tension member 41 fastened to the anchor head 50 (step 5).

  The user fills the gap between the pulled anchor head 50 and the anchor plate 43 with a half crack shim and unloads the traction force of the jack 45. By filling the space between the anchor head 50 and the anchor plate 43 with a half crack shim, the tension force applied to the tension member 41 is retained on the tension member 41 even after unloading, and the user is re-tensioned. It becomes the state. Thereby, the re-tensioning of the anchor 42 is completed (step 6).

  An anchor re-tensioning system 40 according to the present invention includes an anchor head 50 provided at an end of an anchor 42 and provided with a circumferential groove 52 on a side surface, a main body 60a having a cylindrical structure, and a bottom of the main body on the anchor 42 side. The inner periphery includes an engagement portion 60c that engages with the anchor head 50, and includes two half-cylinder pieces 65a and a coupler 60 that is separated into half-cylinder pieces 65b. Even if foreign matter adheres to the anchor head 50 by fitting the cylindrical piece 65b and engaging the engaging portions 60c of the half cylindrical piece 65a and the half cylindrical piece 65b with the circumferential groove 52 of the anchor head 50, it is easy. Thus, it is possible to provide the anchor re-tensioning system 40 that enables the coupler 60 to be attached and reduces the labor of the coupler attachment.

  In addition, the anchor re-tensioning system 40 of the present invention can re-tension the anchor 42 even if rust, deformation, or the like occurs in the anchor head 50 due to the environment in which the anchor 42 (ground anchor) is driven.

  The anchor re-tensioning method of the present invention includes a step of engaging and engaging the separated engaging portions 60c of the half cylinder piece 65a and the half cylinder piece 65b with the circumferential groove 52 of the anchor head 50; The step of screwing the tension bar 44 to the internal thread structure 62, the step of installing the jack 45 so as to surround the tension bar 44, and the screwing of the set nut 46 to the tension bar 44 make it possible to connect the tension bar 44 and the jack. And a step of pulling the tension bar 44 by the jack 45 and a step of re-tensioning the anchor 42 by inserting a shim into the gap of the pulled anchor head 50. Even if foreign matter adheres to the anchor head 50, the coupler 60 can be easily attached. It is possible to provide an anchor re tensioning system 40 to reduce the effort Raa mounting.

  As described above, the anchor re-tension system and the anchor re-tension method of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the gist of the present invention. Changes may be made.

A Pulling direction 10 Anchor re-tensioning system 11 Tensile member 12 Anchor 13 Anchor plate 14 Tension bar 15 Jack 16 Locking nut 20 Anchor head 21 Taper hole 22 Male thread structure 23 Counterbore part 30 Coupler 31 Female thread structure 32 Female thread structure 33 Screwing Surface 40 Anchor re-tensioning system 41 Tensile material 42 Anchor 43 Anchor plate 44 Tension bar 45 Jack 46 Locking nut 50 Anchor head 51 Taper hole 52 Circumferential groove 52a Engagement surface 52b Parallel surface 52c Tapered surface 53 Counterbore 60 Coupler
60a Body portion 60b Inner nut joint portion 60c Engaging portion 61 Inner nut 62 Female thread structure 63 Bolt hole 64 Bolt receiving hole 65a, 65b Half cylinder piece 66 Bolt 67a, 67b Counterbore 68a, 68b Joint hole 69a, 69b Positioning pin receiving hole 71a, 71b Positioning pin

Claims (7)

In the re-tension anchor system that re-tensions the anchor placed in the ground,
An anchor head at the end of the anchor and provided with a circumferential groove on the side surface;
A main body portion of a cylindrical structure and a coupler having an engagement portion that engages with the anchor head on the inner periphery of the bottom portion on the anchor side of the main body portion
The coupler is separated into two half cylinder pieces, and by fitting the half cylinder pieces,
Each of the engaging portions of the half cylinder pieces engages with a circumferential groove of the anchor head.   2. The anchor head according to claim 1, wherein the surface of the circumferential groove in the pulling direction of the engaging portion is a surface orthogonal to the axial direction of the anchor. Tension system.   3. The anchor head according to claim 1, wherein a surface of the circumferential groove in the anchor head has a reverse taper shape with respect to the anchor in a direction opposite to a pulling direction of the engaging portion. Tension system.   The coupler includes at least one positioning pin and a positioning pin receiving hole in each half cylinder piece, and the positioning pin in one half cylinder piece and the positioning pin receiving hole in the other half cylinder piece are inserted. The anchor re-tensioning system according to any one of claims 1 to 3, characterized by being fitted together.   The coupler has an inner nut joint portion on the inner periphery of the lid portion opposite to the anchor side of the main body portion, and includes an inner nut joined to the inner nut joint portion, and has an internal thread structure on the inner periphery of the inner nut. An anchor re-tensioning system according to any one of claims 1 to 4, further comprising: The anchor re-tension system further comprises:
A tension bar having a screw structure at the end on the coupler side and screwed into the female screw structure;
6. An anchor re-tensioning system according to claim 5, further comprising a jack installed around the tension bar. In an anchor re-tensioning method for re-tensioning an anchor placed in the ground,
An anchor head at the end of the anchor and provided with a circumferential groove on the side surface;
An anchor re-tensioning system comprising: a main body portion having a cylindrical structure; and a coupler having an engaging portion that engages with the anchor head on an inner periphery of a bottom portion on the anchor side of the main body portion, and a coupler that is separated into two half-tube pieces. But,
Engaging the engaged portions of the separated half cylinder pieces with the circumferential grooves of the anchor head;
Screwing a tension bar into the female thread structure of the coupler;
Installing a jack around the tension bar;
Fixing the tension bar and the jack by screwing a locking nut to the tension bar;
Pulling the tension bar with the jack;
And a step of re-tensioning the anchor by inserting a shim into the pulled gap of the anchor head.

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