KR20200064506A - Anchor head unit for re-tensioning of strand wire and re-tensioning method of strand wire using the same - Google Patents

Abstract

The present invention relates to an anchor head unit for re-tensioning a steel strand and a re-tensioning method of a steel strand using the same. A ground anchor includes a steel strand holder and a wedge unit fastened to an end portion of a steel strand of an inlet of a grouting hole to be maintained in a state in which tension is given to the steel strand. The steel strand holder includes: a small steel strand holder which is provided as a disk member of a diameter inserted into the inlet of the grouting hole, allows the steel strand to penetrate the disk member, and has several wedge unit holes drilled to place the wedge unit to grip the steel strand, and a fastening structure for fastening to a re-tensioning device on the outer circumferential surface thereof; and a support member installed on the grouting hole to support the steel strand holder while preventing a downward descent from a prescribed position of an inlet portion of the grouting hole. The steel strand in the grouting hole can be aligned and the small steel strand holder can be reinstalled. A tension bar or the like can be connected to the small steel strand holder to be effectively used in an area for re-tensioning a steel strand by a tension cylinder which is one of tensioning means.

Description

ANCHOR HEAD UNIT FOR RE-TENSIONING OF STRAND WIRE AND RE-TENSIONING METHOD OF STRAND WIRE USING THE SAME}

The present invention relates to an anchor head unit for re-tensioning a stranded wire and a method for re-tensioning a stranded wire using the same, more specifically, at the inlet portion of the grouting hole, the stranded wire and the wedge unit in the stranded wire holder are corroded or damaged and the end of the stranded wire is damaged. When located at the entrance of the grouting hole, the present invention relates to a re-tensioning anchor head unit for re-tensioning a strand and a method for re-tensioning a strand using the same.

In general, the ground anchor is drilled by drilling a grouting hole of a predetermined depth into the ground, inserting at least one twisted wire into the grouting hole, and then injecting the grout to prevent the collapse of a slope or retaining wall of the ground during civil engineering or building construction. After that, the steel wire is stretched to give a tensile force to stabilize and reinforce the ground.

The ground anchor is supported by the strand holder so that the ends of the strands extending out of the ground from the grouting hole are gripped through each wedge unit.

The re-tension of the ground anchor constructed as described above is maintained as it was in a state in which tensile strength was applied by tensioning the steel wire at the beginning of construction, but as the time passes, the ground is settled, but the tensile force naturally decreases due to loss of soil and elongation of the steel wire. In some cases, even the steel wire and the wedge unit of the steel wire holder portion were corroded or damaged, and the wedge unit was disassembled in the steel wire.

As described above, when the tensile strength of the stranded wire is lowered or the wedge unit is disassembled, it cannot perform all functions as a ground anchor.

Re-tensioning devices or methods for re-tensioning a steel wire with respect to the re-tensioning of the ground anchor have been disclosed, but among them, a re-tensioning device that can be said to be related to the invention of the application is briefly described. do.

In Utility Model Registration No. 20-0481040 (hereinafter referred to as "document 1"), the end portion of a steel wire settled by a grout at the grouting hole and extended through the entrance of the grouting hole is held by the steel wire holder and the first wedge unit. However, the outer circumferential surface of the strand holder is held by a compression ring and a first casing, which are second wedge units, and a fixing unit is provided in which a second casing is fastened to the first casing. It was to re-tension the strand by tensioning with a tensioning cylinder, one of the tensioning means.

In the registered patent No. 10-0949196 (hereinafter referred to as "document 2"), the end portion of the twisted wire settled by the grout at the grouting hole and extended through the entrance of the grouting hole is gripped by the twisted wire holder and the wedge unit. Hold the outer hook-chin of the holder so that it is caught by the gripping piece, fasten one end of the tensile-inducing rod to the connector of the gripping piece, and then place the tensioning cylinder, which is one of the supporting plates and tensioning means, on the outside of the gripping piece. Was to re-tension the strands by tensioning with a tension cylinder.

In the steel wire re-tensioning device of documents 1 and 2 as described above, if the steel wire is sufficiently extended together with the steel wire holder at the tip entrance of the grouting hole, there is no problem in re-tensioning the steel wire using the re-tensioning device.

However, the steel wire and the wedge unit are corroded or damaged, and the wedge unit is separated from the steel wire and dismantled due to the tensile force applied to the steel wire, and the length of the steel wire also shrinks, so that the end of the steel wire shrinks to the entrance of the grouting hole.

If the end of the strand is reduced to the entrance of the grouting hole as above, it is not possible to re-tension the strand because it is not possible to install the strand holder and the wedge unit at the end of the strand and to grip the end of the strand. Around the ground, there was an end to rebuilding the ground anchor.

(Document 1) KR 20-0481040Y1 (Registration on July 29, 2016) (Document 2) KR 10-0949196B1 (Registration on March 16, 2010)

The present invention has been researched and developed to solve the conventional closed end as described above, by inserting a supporting member and a small stranded wire holder in the inlet portion of the grouting hole to align the stranded wire and connecting a tensile bar, etc. to the small stranded wire holder to tension An object of the present invention is to provide an anchor head unit for re-tensioning a steel wire and a method for re-tensioning a steel wire using the same.

An anchor head unit for re-tensioning a steel wire according to the present invention for solving the above-described problems, includes a wedge unit and a steel wire holder fastened to the end portion of the steel wire at the entrance of the grouting hole so as to maintain the tensile wire in a tensioned state. In the ground anchor, the steel wire holder is provided with a disk member having a diameter inserted at the entrance of the grouting hole, and the steel wire is penetrated through the disk member, and several wedge unit holes for fixing the wedge unit to grip the steel wire are perforated and A small stranded wire holder provided with a fastening structure for fastening with the re-tensioning device on the outer circumferential surface, and a supporting member installed in the grouting hole to support the stranded wire holder while descending downward from a predetermined position of the entrance portion of the grouting hole It is configured by.

In the anchor head unit for re-tensioning a strand according to the present invention, the support member may be provided as a washer-shaped disc and a plurality of wings bent at an upward angle on an outer peripheral surface of the disc.

In the anchor head unit for re-tensioning a strand according to the present invention, the supporting member protrudes a disc having several perforated holes for aligning the strands, and a plurality of wings bent upwardly on the outer peripheral surface of the disc. It can be prepared.

In the anchor head unit for re-tensioning a strand according to the present invention, the support member aligns the strands to facilitate the installation of the strand holders. It is characterized in that an elastic band capable of being supported while preventing the steel wire guide from descending along the grouting hole is provided on the main surface.

The strand-hole of the strand guide is preferably formed so that the lower part is wider and narrower toward the upper part to facilitate insertion and guidance of the strand.

The elastic band is characterized in that it is provided as a ring of a C-shaped incision on one side, and is provided in a cross-sectional shape of an arc convex toward the outside from the top and bottom to the center.

The method for re-tensioning a steel wire using an anchor head unit for re-tensioning a steel wire according to the present invention is a wedge unit in which a steel wire and a wedge unit in a steel wire holder are corroded or damaged at the entrance of a grouting hole of a constructed ground anchor, and thus gripped on the steel wire. When this is released and the end of the strand is located at the entrance of the grouting hole,

A support member installation step of inserting and installing a support member into an inner inlet portion of the grouting hole to align the strands in the grouting hole; A small steel wire holder installation step of placing a small steel wire holder on the support member but hypothesizing the steel wires to pass through each wedge unit hole and installing a wedge unit to grip the steel wire in each wedge unit hole; The small stranded wire holder is fastened to a connection socket at one end of the tension bar, and the casing is installed on the pressure plate to accommodate the stranded wire holder even if the small sized wire holder falls out of the entrance of the grouting hole, and then withdrawn through the casing. A re-tension device installation step of installing a tension cylinder as one of the tension means on the casing so as to pull the tension bar; By operating the tension cylinder and pulling the tension bar together with the small steel wire holder, when the small steel wire holder is pulled out from the entrance of the grouting hole as the steel wires are tensioned, the steel wire is retensioned by interposing the support member into the space between the acupressure plate and the small steel wire holder. It characterized in that it comprises a re-tension step of the steel wire.

According to the re-tensioning method of an anchor head unit for re-tensioning a steel wire of the present invention and a steel wire using the same, the provision of a supporting member and a small steel wire holder inserted into the inner inlet portion of the grouting hole aligns the steel wires in the grouting hole and the small steel wire The holder can be re-installed, and there is a useful effect of re-tensioning the strand with a tension cylinder as one of the tension means by connecting a tension bar or the like to the small strand holder.

In addition, the anchor head unit for re-tensioning a strand according to the present invention and a method for re-tensioning a strand using the same, the support member is provided at the inner inlet portion of the grouting hole by providing a support member protruding a plurality of wings on the outer peripheral surface of the disc. Of course, the small strand holder can be installed at any position of the grouting hole in a state that prevents it from descending below the grouting hole, whereby the strand and wedge units in the strand holder are corroded or damaged at the entrance of the grouting hole of the constructed ground anchor. There is a useful effect to re-tension the steel wire even when the wedge unit gripped at is released and the end of the steel wire is located at the entrance of the grouting hole.

In addition, the steel wire re-tension anchor head unit according to the present invention and the re-tensioning method of the steel wire using the same, the steel wire in the grouting hole is arranged by providing a support member having a number of steel wire holes or a steel wire guide-hole. This has the advantage of being able to easily reinstall the small strand holder in the inlet portion of the grouting hole.

1 is a cross-sectional view of a re-tensioned strand by applying a re-tension anchor head unit of a strand according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view of FIG. 1 in an exploded view.
Figure 3 is a cross-sectional view showing a small steel wire holder and a supporting member that is a main part of the re-tension anchor head unit of a strand according to the present invention.
4 is a perspective view showing another embodiment of the support member in the re-tension anchor head unit of a strand according to the present invention.
5 and 6 are views showing a re-tensioning device for re-tensioning a strand re-tension anchor head unit according to the present invention.
7 to 13 are views for explaining the re-tension process of the strand using the re-tension anchor head unit of the strand according to an embodiment of the present invention.
14 to 15 are views showing another embodiment of the support member in the re-tension anchor head unit of a strand according to the present invention.
16 is a cross-sectional view of a state constructed using another embodiment of the support member in the re-tension anchor head unit of a strand according to the present invention.

Hereinafter, with reference to the accompanying drawings according to a preferred embodiment of the present invention will be described in detail. For reference, the size of a component, the thickness of a line, and the like shown in the drawings referred to for describing the present invention may be exaggerated for convenience of understanding. In addition, the terms used in the description of the present invention are only defined in consideration of the functions in the present invention, and may vary according to a user, an operator's intention, and customs. Therefore, the definition of terms should be made based on the contents of the present specification.

1 to 3 are views for explaining the re-tension anchor head unit of a strand according to an embodiment of the present invention.

As shown in the figure, the re-tension anchor head unit of the strand of the present invention is embedded in the inner inlet portion of the grouting hole 40 and the support member 10, which is embedded in the grouting hole 40 so as to protrude to the ground A small steel wire holder 20 installed together with a wedge unit 42 at one end of the extended steel wires 41 and a pressure plate material 43 at the entrance of the grouting hole () to support the small steel wire holder 20 It comprises a support member 30.

The support member 10 is a disc 11 with a plurality of strand holes 12 for aligning the strands 41, and a plurality of wings 13 bent upwardly on the outer circumferential surface of the disc 11 It consists of. The support member 10 is inserted into the steel wire hole 12 so that the steel wires () pass through each without twisting, and when inserted downward from the entrance of the grouting hole 40, a plurality of provided on the outer peripheral surface of the disc 11 The dog wings 13 are resiliently supported by the inner circumferential surface of the grouting hole 40 while being entangled by the inner circumferential surface of the grouting hole 40 and must be supported without descending below the grouting hole 40. Although the small strand holder 20 is installed on the support member 10 installed in this way, even if the strand 41 is hypothesized to pass through the wedge unit hole 22, it is supported so as not to go down the grouting hole 40.

Although the support member 10 is shown and described as having a drilled hole 12, as shown in one embodiment, as shown in FIG. 4, the disc 11 is provided in a washer-type without a stranded hole 12 And, it may be provided that a plurality of wings 13 are bent obliquely upward on the outer circumferential surface of the original plate (11).

The small strand holder 20 is provided with a disc member 21 of a diameter that is inserted into the inlet portion of the grouting hole 40, and the steel wire 41 is penetrated into the disc member 21 and grips the strand 41. Several wedge unit holes 22 for seating the wedge unit 42 are drilled so that the outer peripheral surface of the disc member 21 is a first male screw 23 which is a fastening structure for fastening with the re-tensioning device 50 Is prepared.

The strand 41 is buried in the grouting hole 40 in the ground, but one end is extended to protrude to the ground, and the end portion of the strand 41 is supported by a small strand holder 20 by a pressure plate 43 It is held by each wedge unit 43 as much as possible. The wedge unit 42 is seated in the wedge unit hole 22 of the small strand holder 20 to maintain the strand 41 in a tensioned state.

The supporting member 30 is a plate material interposed between the small stranded wire holder 20 and the acupressure plate member 43 to support the small stranded wire holder 20, and between the small stranded wire holder 20 and the acupressure plate 43 on the side. When interposed in the plurality of notch grooves 31 are formed in parallel so as not to interfere with the strands (41) passing through the small strand holder (20).

5 and 6 are views for explaining a re-tensioning device for re-tensioning a strand with a strand re-tension anchor head unit according to the present invention.

As shown in the figure, the re-tensioning device 50 is a casing that is installed so that the tensile bar 51 is fastened to the small steel wire holder 20 and the tensile bar 51 is passed through the outside of the small steel wire holder 20. It comprises a 55, and a tension cylinder 57, which is one of the tension means installed on the casing 55 so as to pull the tension bar 51 drawn out through the casing 55.

The tension bar 51 is provided with a connection socket 52 at one end and a second male screw 53 for fastening the pulling nut 58 in the state through which the tension cylinder 57 is provided at the other end. . The connection socket 52 is formed of a cap-shaped cross section having a female thread 52a to be fastened to the first male screw 23 of the small strand holder 20, and a spring 54a is provided inside the connection socket 52. By this, a wedge fixing plate 54 that elastically presses the wedge units 42 may be provided.

The casing 55 is provided with a cap-shaped body 55a to be guided in the direction of the center line of the small strand holder 20 by being covered with the outside of the small strand holder 20 and a tension bar at the top of the body 55a 51) the first through-hole (55b) is formed with a diameter that passes without interference, and one or two cutting grooves (55c) into which the supporting member (30) can be fitted are formed on the side surface of the body (55a).

The tension cylinder 57 is a hydraulic cylinder including a piston rod 57b together with a piston in the cylindrical cylinder 57a, and fluid is introduced or introduced from the outside through the upper and lower ports of the cylindrical cylinder 57a. As the fluid is discharged, the piston rod 57b is raised and lowered together with the piston, and a second through hole 57c is formed in the center of the piston rod 57b to allow the tensile bar 51 to pass therethrough.

Steel wire re-tension method using the re-tension anchor head unit and the re-tension device of the steel wire according to the present invention configured as described above, grouting at the ground anchor constructed in the grouting hole 40 of the underground, as shown in FIG. The steel wire 41 and the wedge unit 42 in the steel wire holder installed at the entrance portion of the hole 40 are corroded or damaged, so that the wedge unit 42 gripped by the steel wire 41 is released and tensioned at the same time ( 41) is contracted and can be applied when the end of the strand 41 is located at the entrance of the grouting hole 40.

As described above, the method of re-tensioning the stranded wire will be sequentially described when the stranded wire 41 and the wedge unit 42 are released from the stranded holder.

1) Support member installation step

First, as shown in FIG. 8, the support member 10 is inserted and installed at a predetermined depth from the entrance of the grouting hole 40 to the inside. The installation of the support member 10 is performed by pushing a predetermined depth into the grouting hole 40 so that the strands 41 in the grouting hole 40 pass through each of the strands 12 drilled in the disk 11. The wings 13 of the 11) are inserted as they come and go, and the strands 41 in the grouting hole 40 are aligned without twist by the strands 12 of the disc 11. At this time, the support member 10 is in a state of being resiliently in close contact with the inner surface of the grouting hole 40 by the elasticity that the wings 13 return to their original shape in the outer circumference of the original plate 11.

2) Small steel wire holder installation step

Each of the strands 41 is inserted through the entrance of the grouting hole 40 while passing through each wedge unit hole 22 formed in the small strand holder 20, and the small strand holder 20 is placed on the support member 10. After placing, the wedge unit 42 is installed to grip the steel wire 41 for each wedge unit hole 22 formed in the small steel wire holder 20 (see FIG. 9).

At this time, the support member 10 and the small strand holder 20 are the support members 10 because the wings 13 of the disk 11 constituting the support member 10 are elastically and closely supported on the inner surface of the grouting hole 40 Even if the small steel wire holder 20 is placed on the top, it does not go down to the grouting hole 40.

3) Re-tension device installation step

A wedge fixing plate 54 including a spring 54a is placed on the wedge unit 42 of the small strand holder 20, and then the connection socket 52 is connected to the first male screw 23 of the small strand holder 20 ) Connect the connection socket 52 of the tension bar 51 so that the female thread 52a of the) is fastened. Thus, when the connecting socket 52 is fastened to the small strand holder 20, the wedge fixing plate 54 is pressed by the elastic force of the spring 54a to press the wedge unit 42 installed in each wedge unit hole 22. The wedge unit 42 is prevented from being detached from the wedge unit hole 22 of the small strand holder 20.

The tensile bar 51 is the first through hole 55b while receiving the connecting socket 52 of the tensile bar 51 on the acupressure plate 43 at the entrance of the grouting hole 40 as well as the small strand holder 20. The casing 55 is installed so as to penetrate therethrough.

Tensile cylinder (57) so that the tensile bar (51) drawn out through the first through hole (55b) of the casing (55) passes through the second through hole (57c) provided in the piston rod (57b) of the cylindrical cylinder (57a). After installation, the pulling nut 58 is fastened to the second male screw 53 of the tension bar 51 drawn through the second through hole 57c of the piston rod 57b (see FIG. 10).

4) Steel wire re-tensile stage

When the piston rod (57b) with the piston rises to protrude upwards by introducing and discharging fluid to the upper and lower ports of the tension cylinder (57), by pulling the small strand holder (20) together with the tension bar (51). In the wedge unit hole 22 of the small-sized strand holder 20, the strands 41 gripped by the wedge unit 42 start to be tensioned, and the strands 41 are started to be tensioned, so that the small strand holder 20 is grouting. It is pulled out to some extent from the entrance of the hole 40 (see FIG. 11). As described above, when the small steel wire holder 20 is sufficiently withdrawn and a predetermined tensile force is applied to the steel wire 41, between the pressure plate member 43 and the small steel wire holder 20 through the cutting groove 55c of the casing 55 The steel wire is re-tensioned by interposing one or two supporting members 30 into the space (see FIG. 12).

5) Re-tension device removal step

When the re-tension of the strand is completed as above, the fluid is reversely introduced and discharged to the upper and lower ports of the tensile cylinder 57 to lower the piston rod 57b together with the piston to be lowered, and then the tensile cylinder 57 Loosen and remove the pull nut 58 fastened to the piston rod 57b, and remove and remove the tension cylinder 57, casing 55, and tension bar 51 sequentially to complete the re-tensioning work of the strand ( See Figure 13).

14 to 16 are views showing another embodiment of the support member in the re-tension anchor head unit of a strand according to the present invention. Here, the support member 10 aligns the strands 41 so as to facilitate the installation of the small strand holders 20, the strand guide-holes 16 are perforated by the number of the strands, and the strand guides 15 are perforated. On the outer circumferential surface of (15), the strand guide 15 is provided with an elastic band 17 that can be supported while preventing descending along the grouting hole 40.

It is preferable that the steel wire guide-hole 16 of the steel wire guide 15 is formed in a vertebral shape having a wide lower portion and a narrower shape toward the upper portion to facilitate insertion and guidance of the steel wire 41.

The elastic band 17 is provided with a ring of a C-shaped incision on one side, and is provided in a cross-sectional shape of a convex arc toward the center from the top and bottom.

According to the present invention of the other embodiment configured as described above, since the steel wire guide-hole 16 of the steel wire guide 15 is formed in a vertebral shape, it is covered with the support member 10, but the grouting hole 40 is not visible to the operator. The end of the strands 41 located at the inlet portion of the lead is easily inserted and thereby facilitates the construction of the support member 10 in the grouting hole 40 as well as the alignment of the strands 41 as well. It is possible.

As described above, the present invention has been described with reference to specific embodiments, but the present invention is not limited by the embodiments disclosed in the description of the present invention and the accompanying drawings, and is variously understood by those skilled in the art without departing from the spirit of the present invention. It can be transformed.

10: support member 11: disc
12: Lecture Hall 13: Wings
15: Guide to Steel Wire 16: Guide to Steel Wire-Hall
17: elastic band 20: small strand holder
21: disc member 22: wedge unit hole
23: first male screw 30: support member
40: Grouting Hall 41: Lecture Line
42: wedge unit 43: acupressure plate
50: re-tension device 51: tension bar
52: connecting socket 54: wedge fixing plate
55: casing 57: tension cylinder
58: pull nut

Claims (5)

In the ground anchor comprising a wedge unit and a steel wire holder fastened to the end portion of the steel wire at the entrance of the grouting hole so as to maintain the tensile force to the steel wire,
The steel wire holder is provided with a disc member having a diameter inserted at the entrance of the grouting hole, and the steel wire is penetrated through the disc member, and several wedge unit holes for seating the wedge unit to grip the steel wire are perforated and re-tensioned on the outer peripheral surface. Small steel wire holder with a fastening structure for fastening with the device,
An anchor head unit for re-tensioning a stranded wire comprising a support member installed in the grouting hole to support the stranded wire holder while preventing it from descending downward from a predetermined position at an entrance portion of the grouting hole. The method according to claim 1,
The support member is an anchor head unit for re-tensioning a strand of a steel wire, characterized in that it is provided with a washer-shaped disc and a plurality of wings bent upward to the outer circumferential surface of the disc. The method according to claim 1,
The support member is an anchor head unit for re-tensioning a strand, characterized in that it is provided by protruding a disc having several perforated holes for aligning a strand, and protruding a plurality of wings bent upward to the outer circumferential surface of the disc. . The method according to claim 1,
The support member can be supported while arranging the strands so as to facilitate the installation of the strand holders, the steel wire guide-hole guides with holes drilled, and the steel wire guides on the outer circumferential surface of the strand guides while descending along the grouting hole. Anchor head unit for re-tensioning a strand, characterized in that an elastic band is provided. When the steel wire and the wedge unit in the steel wire holder are corroded or damaged at the entrance of the grouting hole of the constructed ground anchor, the wedge unit gripped by the steel wire is released, and the end of the steel wire is located at the entrance of the grouting hole.
A support member installation step of inserting and installing a support member into an inner inlet portion of the grouting hole to align the strands in the grouting hole;
A small steel wire holder installation step of placing a small steel wire holder on the support member, hypothesizing the steel wires to pass through each wedge unit hole, and installing a wedge unit to grip the steel wire for each wedge unit hole;
The small stranded wire holder is fastened to a connection socket at one end of the tension bar, and the casing is installed on the pressure plate to accommodate the stranded wire holder even if the small sized wire holder falls out of the entrance of the grouting hole, and then withdrawn through the casing. A re-tension device installation step of installing a tension cylinder as one of the tension means on the casing so as to pull the tension bar;
By operating the tension cylinder and pulling the tension bar together with the small strand holder, when the small strand holder is pulled out from the entrance of the grouting hole, the tension member is retensioned by interposing the support member into the space between the acupressure plate and the small strand holder. Method for re-tensioning a steel wire using an anchor head unit for re-tensioning the steel wire including the re-tensioning step.

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