U.S. patent application number 12/096304 was filed with the patent office on 2008-12-11 for internal fixer for anchor having releasable tensioning steel wire.
Invention is credited to Jong Duck Shin.
Application Number | 20080302035 12/096304 |
Document ID | / |
Family ID | 38355504 |
Filed Date | 2008-12-11 |
United States Patent
Application |
20080302035 |
Kind Code |
A1 |
Shin; Jong Duck |
December 11, 2008 |
Internal Fixer For Anchor Having Releasable Tensioning Steel
Wire
Abstract
The present invention provides an internal fixer for an anchor
having a releasable tensioning steel wire. The internal fixer of
the present invention includes a first outer body (10), which is
provided with a tube coupling hole (11), a body seating hole (13)
and a wedge receiving body support means; and a wedge receiving
body (30), which is seated in the body seating hole (13) and has a
conical wedge seating hole (31), into which separated wedge bodies
(41) are seated. The internal fixer further includes a wedge unit
(40), which is seated in the wedge seating hole (31) of the wedge
receiving body (30) and comprises the three separated wedge bodies
(41); and a second outer body (20), which supports and covers both
the wedge receiving body (30), which is seated in the body seating
hole (13), and the wedge unit (40), which is placed in the wedge
seating hole (31).
Inventors: |
Shin; Jong Duck;
(Gyeonggi-do, KR) |
Correspondence
Address: |
KELLEY DRYE & WARREN LLP
400 ALTLANTIC STREET , 13TH FLOOR
STAMFORD
CT
06901
US
|
Family ID: |
38355504 |
Appl. No.: |
12/096304 |
Filed: |
May 26, 2006 |
PCT Filed: |
May 26, 2006 |
PCT NO: |
PCT/KR06/02004 |
371 Date: |
June 5, 2008 |
Current U.S.
Class: |
52/223.13 |
Current CPC
Class: |
E02D 5/805 20130101;
E02D 5/765 20130101; E02D 5/80 20130101 |
Class at
Publication: |
52/223.13 |
International
Class: |
E02D 5/80 20060101
E02D005/80 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 5, 2005 |
KR |
10-2005-0117469 |
May 23, 2006 |
KR |
10-2006-0046130 |
Claims
1. An internal fixer for an anchor having a releasable tensioning
steel wire, comprising: a first outer body (10), with a tube
coupling hole (11) and a body seating hole (13) coaxially formed in
the first outer body (10) so that the tensioning steel wire (50)
passes therethrough, and wedge receiving body support means
provided on an inner surface of the body seating hole (13); a wedge
receiving body (30) seated by the wedge receiving body support
means in the body seating hole (13) and having a conical wedge
seating hole (31), into which separated wedge bodies (41) are
seated; a wedge unit (40) seated into the wedge seating hole (31)
of the wedge receiving body (30) and comprising the three separated
wedge bodies (41), which are arranged in a cone shape to hold the
tensioning steel wire (50); and a second outer body (20) supporting
and covering both the wedge receiving body (30), which is seated in
the body seating hole (13) of the first outer body (10), and the
wedge unit (40), which is placed in the wedge seating hole (31) of
the wedge receiving body (30).
2. An internal fixer for an anchor having a releasable tensioning
steel wire, comprising: a first outer body (10), with a tube
coupling hole (11) and a body seating hole (13) coaxially formed in
the first outer body (10) so that the tensioning steel wire (50)
passes therethrough, and wedge receiving body support means
provided on an inner surface of the body seating hole (13); a wedge
receiving body (30) seated by the wedge receiving body support
means in the body seating hole (13) and having a conical wedge
seating hole (31), in which separated wedge bodies (41) are seated;
a wedge unit (40) seated into the wedge seating hole (31) of the
wedge receiving body (30) and comprising the three separated wedge
bodies (41), which are arranged in a cone shape to hold the
tensioning steel wire (50); a second outer body (20) supporting and
covering the wedge receiving body (30), which is seated in the body
seating hole (13) of the first outer body (10); and an elastic
support member (70) provided in the second outer body (20) and
elastically supporting, pushing and seating the wedge unit (40),
which is placed in the wedge seating hole (31) of the wedge
receiving body (30), into the wedge seating hole (31).
3. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 1 or 2, wherein the wedge
receiving body support means of the first outer body (10) along
with the second outer body (20) supports the wedge receiving body
(30) while no tensile force is applied to the tensioning steel wire
(50), and the wedge receiving body support means allows the wedge
receiving body (30) to be advanced along with the wedge unit (40)
and to be fastened when tensile force is applied to the tensioning
steel wire (50) after the internal fixer is installed in
ground.
4. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 3, wherein the wedge
receiving body support means comprises a support protrusion (13a)
provided on the inner surface of the body seating hole (13).
5. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 3, wherein the wedge
receiving body support means is realized by a tapered inner surface
of the body seating hole (13) which decreases in diameter from a
deep portion thereof to a shallow portion thereof.
6. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 4 or 5, wherein the
tapered inner surface of the body seating hole (13) and the support
protrusion (13a), which is provided on the inner surface of the
body seating hole (13), are formed in ring shapes around an entire
circumference of the body seating hole (13).
7. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 4 or 5, wherein the
tapered inner surface of the body seating hole (13) and the support
protrusion (13a) respectively comprise a plurality of tapered inner
surfaces of the body seating hole (13) and a plurality of support
protrusions (13a), which are provided on the inner surface of the
body seating hole (13) and are spaced apart from each other.
8. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 4, wherein the support
protrusion (13a) of the body seating hole (13) is
multi-stepped.
9. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 3, wherein the wedge
receiving body support means comprises a support O-ring (14)
provided in a ring groove (13b) formed in the inner surface of the
body seating hole (13), such that, when the wedge receiving body
(30) is advanced by the tensioning steel wire (50), the support
O-ring (14), which has supported an end of the wedge receiving body
(30), comes into close contact with and holds an outer surface of
the wedge receiving body (30).
10. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 3, wherein the wedge
receiving body support means comprises a C-shaped metal ring (15),
which elastically expands in diameter and is provided in a ring
groove (13b) formed in the inner surface of the body seating hole
(13), such that, when the wedge receiving body (30) is advanced by
the tensioning steel wire (50), the C-shaped metal ring (15), which
has supported an end of the wedge receiving body (30), holds an
outer surface of the wedge receiving body (30).
11. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 10, wherein a ring stop
groove (32) is formed in the outer surface of the wedge receiving
body (30), such that, when the wedge receiving body (30) is
advanced, the metal ring (15) is locked to the ring stop groove
(32).
12. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 10 or 11, wherein the
wedge receiving body support means comprises: the C-shaped metal
ring (15) provided in a ring seating groove (33) of the wedge
receiving body (30); and a ring stop groove (13c) formed in the
inner surface of the wedge seating groove (13).
13. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 1 or 2, further
comprising: a wedge returning member (60) provided in the body
seating hole (13) of the first outer body (10), so that, when the
wedge receiving body (30) along with the wedge unit (40) is
advanced and fastened to the body seating hole (13), the wedge unit
(40), which is placed in the wedge seating hole (31) of the wedge
receiving body (30), is biased backwards by the wedge returning
member (60).
14. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 13, wherein the wedge
returning member (60) comprises a compression coil spring.
15. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 13 or 14, further
comprising: a support ring member (61), having a flange on an end
thereof, provided on an end of the wedge returning member (60) to
support lower ends of the separated wedge bodies (41).
16. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 13 or 14, wherein a spring
seating hole (17) is formed in a bottom of the body seating hole
(13) so that the wedge returning member (60) is installed in the
spring seating hole (17), and a support protrusion (17a) is
provided on a bottom of the spring seating hole (17) to hold an end
of the wedge returning member (60).
17. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 2, further comprising: a
cap member (45) fitted into an inner ring groove (43) formed in
upper ends of the separated wedge bodies (41) constituting the
wedge unit, so that an elastic support member (70) is fitted over
the cap member (45) and the tensioning steel wire (50) is inserted
more deeply.
18. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 2 or 17, wherein the
elastic support member (70) comprises a compression coil spring
fitted over an outer surface of the cap member (45), which
protrudes from the upper end of the wedge unit (40), without
moving.
19. The internal fixer for the anchor having the releasable
tensioning steel wire according to claim 2 or 17, further
comprising: a compression cover (71) provided between the separated
wedge bodies (41) and the elastic support member (70) and seated on
the separated wedge bodies (41) outside the cap member (45).
Description
TECHNICAL FIELD
[0001] The present invention relates, in general, to internal
fixers for anchors having releasable tensioning steel wires and,
more particularly, to an internal fixer for an anchor having a
releasable tensioning steel wire in which, when the tensioning
steel wire is tensioned, a wedge receiving body along with
separated wedge bodies is moved in the direction in which the
tensioning steel wire is tensioned, and is fastened, so that the
space required for movement of a wedge unit when the tensile force
is removed is ensured, and in which only the separated wedge bodies
are moved backwards by repulsive force generated when the tensile
force is removing from the tensioning steel wire in the fixed state
of the wedge receiving body, or by both the force of striking the
tensioning steel wire inwards and the restoring force of a spring,
and they are separated in the diameter direction, so that the
tensioning steel wire can be easily and reliably removed.
BACKGROUND ART
[0002] Generally, ground anchors are used in engineering work such
as bracing work and engineering work for stabilizing a tunnel
portal or for reinforcing a stone wall or a retaining wall. For
construction of a ground anchor, a hole is bored at a desired
position in soft ground using a boring machine, and a grout hose
and a load-carrying body, which includes the tensioning steel wire
and the internal fixer, are inserted into the boring hole, before
grout is injected through the grout hose. After the injected grout
cures with the load-carrying body, an external fixer is coupled to
the other end of the tensioning steel wire. Thereafter, the
tensioning steel wire is pulled by a tensioning machine, so that
the grout and ground are tensioned, thus reinforcing the soft
ground.
[0003] Such a ground anchor has advantages of efficient
construction management when working in urban areas and reduction
in construction period. However, in the case that other engineering
work is being conducted adjacent to the area in which the ground
anchor is installed, because the tensioning steel wire has six
times the strength of a typical steel wire per unit area, an
excavator and a boring machine may be damaged, and the construction
period may be increased. To solve the above-mentioned problem, a
ground anchor, which has a structure such that a tensioning steel
wire is removable depending on the construction process after
excavation work has been completed, was developed.
[0004] Various internal fixers for anchors having releasable
tensioning steel wires have been proposed. Of them, two will be
explained herein below. First, in a technique proposed in Korean
Patent Registration No. 10-0447967, which was filed by the inventor
of the present invention, a wedge unit is elastically supported by
a spring in a wedge unit installation space of an anchor body, and
a tensioning steel wire is inserted into and held by the wedge
unit. In this technique, a process, in which the tensioning steel
wire is instantaneously moved backwards and released by striking a
strand or strands of the tensioning steel wire and, simultaneously,
after the strand of the tensioning steel wire is inserted, the
tensioning steel wire is held while the wedge unit is inserted into
the wedge unit installation space by the elasticity of the spring,
is repeated several times. Thus, at the moment at which an end of
the tensioning steel wire other than the struck strand escapes from
the wedge unit, the tensioning steel wire is released. Thereafter,
the tensioning steel wire is pulled out, thus being removed.
[0005] Furthermore, in an internal fixer for an anchor having a
releasable tensioning steel wire in Korean Utility Model
Registration No. 20-0309952, a tensioning steel wire is inserted
into a main body until it reaches separated wedge bodies and a
repulsive force transmission cap through a coned disc spring and a
wedge receiving body.
[0006] Furthermore, an elastic spring, which is provided on the
upper end of the repulsive force transmission cap, is locked to a
support stop of a cover cap. The wedge receiving body is
elastically installed in the main body. The separated wedge bodies
are seated in the wedge receiving body.
[0007] In the internal fixer of the above Korean Utility Model
having the above-mentioned construction, when the tensioning steel
wire is tensioned, the repulsive force transmission cap and the
wedge receiving body, which are coupled to the separated wedge
bodies, are moved along with the separated wedge bodies in the
direction in which the tensioning steel wire is tensioned, and the
coned disc spring is compressed. Thereafter, when the tensioning
steel wire is cut, the repulsive force transmission cap and the
separated wedge bodies are moved by the repulsive force. Then, the
elastic spring of the repulsive force transmission cap is locked to
a locking groove of the cover cap. At this position, because the
separated wedge bodies are in a state of being slightly removed
from the wedge receiving body, the separated wedge bodies are
separated in the diameter direction, so that the tensioning steel
wire may be removed by pulling.
DISCLOSURE OF INVENTION
Technical Problem
[0008] In the internal fixer disclosed in Korean Patent
Registration No. 10-0447967, which was filed by the inventor of the
present invention, because the tensioning steel wire is pushed out
and removed by striking and inserting a strand and strands of the
tensioning steel wire, the tensioning steel wire can be reliably
removed even if the anchor head, which is the internal fixer, rusts
due to water that permeates the anchor head. However, because the
number of times a strand of the tensioning steel wire must be
struck typically reaches several tens of times, work efficiency is
reduced. As well, there is a problem in that, since physical
fatigue increases as the work progresses, a worker may fail to
carry out the work.
[0009] Meanwhile, in the internal fixer disclosed in Korean Utility
Model Registration No. 20-0309952, the repulsive force transmission
cap and the separated wedge bodies are moved by repulsive force
generated when cutting the tensioning steel wire, thereby the wedge
receiving body is moved in the same direction. Therefore, expansion
of the separated wedge bodies is unreliable. To solve this, the
length of the main body is increased, and thus there is a problem
of increased material cost.
[0010] In particular, because a process of cutting the tensioning
steel wire is typically conducted using an oxygen cutting machine,
the strands of the tensioning steel wire are consecutively cut one
by one or in groups of two, but not all at the same time. Thus, the
repulsive force of the tensioning steel wire is generated slowly.
Therefore, this repulsive force may not be enough for the elastic
spring, which is provided on the upper end of the repulsive force
transmission cap, to reach the locking groove of the cover cap. In
this case, the elastic spring, which is provided on the upper end
of the repulsive force transmission cap, is not locked to the
locking groove of the cover cap, so that the separated wedge bodies
remain in the wedge receiving body without expanding in diameter.
As a result, the tensioning steel wire might not be removed.
Technical Solution
[0011] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the prior art, and objects of
the present invention will be presented herein below.
[0012] A first object of the present invention is to provide an
internal fixer for an anchor having a releasable tensioning steel
wire in which, when the tensioning steel wire is tensioned after
the internal fixer is installed in the ground, a wedge receiving
body along with a wedge unit is moved in the direction in which the
tensioning steel wire is tensioned, and is fastened, so that the
space required for movement of a wedge unit when the tensile force
is removed is reliably ensured, and in which only the separated
wedge bodies are moved backwards by repulsive force generated when
removing the tensile force from the tensioning steel wire when the
wedge receiving body is in a fixed state, or by the force of
striking the tensioning steel wire inwards, and they are expanded
in diameter, so that the tensioning steel wire can be easily and
reliably removed.
[0013] A second object of the present invention is to provide an
internal fixer in which a wedge returning member is additionally
provided at a lower position in a body receiving hole of a first
outer body, so that, when the tensioning steel wire is cut to
remove it after having been tensioned, the wedge returning member
pushes the wedge unit backwards from the wedge seating hole of the
wedge receiving body, thus the separated wedge bodies of the wedge
unit are separated in the diameter direction, thereby the
tensioning steel wire is easily released.
[0014] A third object of the present invention is to provide an
internal fixer, in which, when the tensioning steel wire is
inserted into the internal fixer, the separated wedge bodies are
pushed backwards from the wedge seating hole of the wedge receiving
body and expand in diameter, so that the end of the tensioning
steel wire is inserted into the separated wedge bodies and,
thereafter, when the force that has been applied to the tensioning
steel wire is removed, the separated wedge bodies are inserted into
the wedge seating hole of the wedge receiving body by the restoring
force of the elastic support member, so that the tensioning steel
wire can be easily held by the wedge unit, that is, the assembly of
the tensioning steel wire can be easily realized merely by
inserting and releasing the tensioning steel wire.
[0015] A fourth object of the present invention is to provide an
internal fixer in which a cap member, which protrudes from the
upper end of the wedge unit, is provided, so that, because the
elastic support member is seated onto the wedge unit and is fitted
over the outer surface of the cap member, operational precision is
ensured and the elastic support member does not become misaligned
or undesirably move, and, as well, the end of the tensioning steel
wire, which is inserted through a tube coupling hole of the first
outer body, is inserted into the cap member via the separated wedge
bodies, so that the tensioning steel wire is reliably held by the
separated wedge bodies, and, as the separated wedge bodies hold the
tensioning steel wire more strongly, the part of the tensioning
steel wire that is in the cap member becomes untwisted, thus the
diameter of that part of the tensioning steel wire is slightly
increased, thereby the tensioning steel wire can be more securely
held, as if a stop protrusion were formed on the tensioning steel
wire.
[0016] A fifth object of the present invention is to provide an
internal fixer in which the elastic support member and the wedge
returning member respectively comprise a compression coil spring
which is fitted over the cap member protruding from the upper end
of the wedge unit, and a compression coil spring which supports the
lower end of the separated wedge bodies of the wedge unit, so that
the number of elements is minimized, thus reducing the
manufacturing cost, and enhancing workability.
Advantageous Effect
[0017] In the internal fixer for an anchor having a releasable
tensioning steel wire according to the present invention, when the
tensioning steel wire is tensioned after the internal fixer has
been installed in the ground, a wedge receiving body along with a
wedge unit is moved in the direction, in which the tensioning steel
wire is tensioned, and is fastened, so that the space required for
movement of a wedge unit when the tensile force is removed is
reliably ensured. Furthermore, only the separated wedge bodies are
moved backwards and expanded in diameter by repulsive force
generated when the tensile force of the tensioning steel wire is
removed when the wedge receiving body is in a fixed state, or by
the force of striking the tensioning steel wire inwards, so that
the tensioning steel wire can be easily and reliably removed.
[0018] As well, a wedge returning member is additionally provided
at a lower position in a body receiving hole of a first outer body,
so that, when the tensioning steel wire is cut to remove it after
having been tensioned, the wedge returning member pushes the wedge
unit backwards from the wedge seating hole of the wedge receiving
body, thus the separated wedge bodies of the wedge unit are
separated in a diameter direction, thereby the tensioning steel
wire is easily released.
[0019] In addition, when the tensioning steel wire is inserted into
the internal fixer, the separated wedge bodies are pushed backwards
from the wedge seating hole of the wedge receiving body and
expanded in diameter, so that the end of the tensioning steel wire
is inserted into the separated wedge bodies and, thereafter, when
the force that has been applied to the tensioning steel wire is
removed, the separated wedge bodies are inserted into the wedge
seating hole of the wedge receiving body by the restoring force of
the elastic support member, so that the tensioning steel wire can
be easily held by the wedge unit. In other words, the assembly of
the tensioning steel wire can be easily realized merely by
inserting and releasing the tensioning steel wire.
[0020] Moreover, a cap member, which protrudes from the upper end
of the wedge unit, is provided, so that, because the elastic
support member is seated onto the wedge unit and fitted over the
outer surface of the cap member, operational precision is ensured
and the elastic support member does not become misaligned or
undesirably move. As well, the end of the tensioning steel wire,
which is inserted through a tube coupling hole of the first outer
body, is inserted into the cap member via the separated wedge
bodies, so that the tensioning steel wire is reliably held by the
separated wedge bodies, and, as the separated wedge bodies hold the
tensioning steel wire more strongly, the part of the tensioning
steel wire that is in the cap member becomes untwisted, thus the
diameter of that part of the tensioning steel wire is slightly
increased, thereby the tensioning steel wire can be held more
securely, as if a stop protrusion were formed on the tensioning
steel wire.
[0021] Finally, the elastic support member and the wedge returning
member respectively comprise a compression coil spring, which is
fitted over the cap member protruding from the upper end of the
wedge unit, and a compression coil spring, which supports the lower
end of the separated wedge bodies of the wedge unit, so that the
number of elements is minimized, thus reducing the manufacturing
cost and enhancing workability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a sectional view showing an internal fixer for an
anchor having a releasable tensioning steel wire, according to an
embodiment of the present invention;
[0023] FIG. 2 is an exploded perspective view of FIG. 1;
[0024] FIG. 3 is a sectional view showing the tensioning steel wire
in a state of being tensioned in the internal fixer according to
the present invention;
[0025] FIG. 4 is a sectional view showing the tensioning steel wire
released from a wedge unit in the internal fixer according to the
present invention;
[0026] FIGS. 5 through 11 are views showing embodiments of a wedge
receiving body support means of the internal fixer according to the
present invention;
[0027] FIG. 12 is a sectional view showing an internal fixer for an
anchor having a releasable tensioning steel wire, a wedge returning
means being provided for a wedge unit, according to another
embodiment of the present invention;
[0028] FIGS. 13 through 15 are views illustrating processes in
which the tensioning steel wire is held by the internal fixer,
tensioned, and released from the internal fixer according to
present invention;
[0029] FIG. 16 is a sectional view showing an internal fixer for an
anchor having a releasable tensioning steel wire, a wedge returning
means being provided in a wedge unit, according to another
embodiment of the present invention; and
[0030] FIGS. 17 through 19 are views showing internal fixers for
anchors having releasable tensioning steel wires, a wedge support
means being provided in wedge units, according to another
embodiment of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0031] In order to accomplish the above objects, the present
invention provides an internal fixer for an anchor having a
releasable tensioning steel wire, including: a first outer body,
with a tube coupling hole and a body seating hole coaxially formed
in the first outer body so that the tensioning steel wire passes
therethrough, and a wedge receiving body support means provided on
an inner surface of the body seating hole; a wedge receiving body
seated by the wedge receiving body support means in the body
seating hole and having a conical wedge seating hole, into which
separated wedge bodies are seated; a wedge unit seated into the
wedge seating hole of the wedge receiving body and comprising the
three separated wedge bodies, which are arranged in a cone shape to
hold the tensioning steel wire; and a second outer body supporting
and covering the wedge receiving body, which is seated in the body
seating hole of the first outer body, and the wedge unit, which is
placed in the wedge seating hole of the wedge receiving body.
[0032] The second outer body has a shape such that it supports and
covers the wedge receiving body, which is seated in the body
seating hole of the first outer body, and an elastic support member
is provided in the second outer body and elastically supports,
pushes and seats the wedge unit, which is placed in the wedge
seating hole of the wedge receiving body, into the wedge seating
hole.
[0033] In the internal fixer for the anchor having the releasable
tensioning steel wire according to the present invention, it is
sufficient if the wedge receiving body support means of the first
outer body has a structure such that, when tensile force is applied
to the tensioning steel wire, the wedge receiving body is advanced
along with the wedge unit and fastened to the bottom of the body
seating hole.
[0034] The wedge receiving body support means may comprise a
support protrusion, which protrudes from the inner surface of the
body seating hole. The support protrusion may have a ring shape,
which is formed around the entire circumference of the body seating
hole, or, alternatively, may comprise a plurality of support
protrusions, which are spaced apart from each other. The support
protrusion may have various shapes, such as a rounded
cross-section, a rectangular cross-section or a trapezoidal
cross-section.
[0035] Furthermore, the wedge receiving body support means may be
realized by a tapered inner surface of the body seating hole which
is reduced in diameter from a deep portion thereof to a shallow
portion thereof.
[0036] The wedge receiving body support means may comprise at least
one support O-ring or expandable C-shaped metal ring, which is
provided in a ring groove formed in the inner surface of the body
seating hole, such that, when the wedge receiving body is advanced
by the tensioning steel wire, it comes into close contact with and
holds the outer surface of the wedge receiving body. In the case
that the C-shaped metal ring is used, a ring stop groove may be
formed in the inner surface of the wedge seating groove, so that,
when the wedge receiving body is advanced by the tensioning steel
sire, the C-shaped metal ring is locked to the ring stop
groove.
[0037] As well, a C-shaped metal ring may be provided on the outer
surface of the wedge receiving body. In this case, a ring stop
groove is formed in the inner surface of the body seating hole.
[0038] The internal fixer for the anchor having the releasable
tensioning steel wire according to the present invention may
further include a wedge returning member, which is provided in the
body seating hole of the first outer body, so that, when the wedge
receiving body along with the wedge unit is advanced and fastened
to the body seating hole, the wedge unit, which is placed in the
wedge seating hole of the wedge receiving body, is biased backwards
by the wedge returning member.
[0039] The wedge returning member suffices as a compression coil
spring. A ring member, which has a flange on an end thereof, may be
provided on an end of the wedge returning member to support lower
ends of the separated wedge bodies.
[0040] The wedge returning member may comprise a spring seating
hole, which is formed in the bottom of the body seating hole for
installation of the wedge returning member, and a support
protrusion, which is provided on the bottom of the spring seating
hole to hold the end of the wedge returning member.
[0041] In the internal fixer for the anchor having the releasable
tensioning steel wire according to the present invention, the
elastic support member may be provided in the second outer body to
elastically push and seat the wedge unit into the wedge seating
hole of the wedge receiving body. The elastic support member
suffices as a compression coil spring. A cap member may be provided
in an inner ring groove, which is formed in upper ends of the
separated wedge bodies constituting the wedge unit, so that an
elastic support member is fitted over the cap member and the
tensioning steel wire is more deeply inserted into the cap
member.
[0042] Furthermore, a compression cover may be provided on the
separated wedge bodies outside the cap member between the separated
wedge bodies and the elastic support member to ensure reliable
expansion of the separated wedge bodies.
MODE FOR THE INVENTION
[0043] Hereinafter, an internal fixer for an anchor having a
releasable tensioning steel wire according to the present invention
will be described in detail with reference to the attached
drawings.
[0044] FIG. 1 is a sectional view showing the internal fixer for
the anchor having the releasable tensioning steel wire, according
to an embodiment of the present invention. FIG. 2 is an exploded
perspective view of FIG. 1.
[0045] As shown in the drawings, in the internal fixer for the
anchor having the releasable tensioning steel wire according to the
present invention, a wedge receiving body 30 is installed in first
and second outer bodies 10 and 20, and a wedge unit 40 is inserted
into the wedge receiving body 30 and is supported by the second
outer body 20 such that the wedge unit 40 is prevented from being
undesirably removed from the wedge receiving body 30. The wedge
unit 40 has a structure such that, when the releasable tensioning
steel wire 30 is inserted into the wedge unit 40 through a tube
coupling hole 11 of the first outer body 10, the wedge unit 40
holds the tensioning steel wire 30. Typically, the tensioning steel
wire 30 comprises seven strands of steel wires, in which six
strands of steel wires are twisted around a center steel wire at a
regular pitch.
[0046] The first outer body 10 has the tube coupling hole 11,
through which the tensioning steel wire 30 is inserted, and a body
seating hole 13, which is coaxially formed therein, and in which
the wedge receiving body 30 is seated. Furthermore, a support
protrusion 13a, which is a means for supporting the wedge receiving
body 30, is provided on the circumferential inner surface of the
body seating hole 13, so that, while no tension is applied to the
tensioning steel wire 50, the wedge receiving body 30 is seated at
a rear position of the first outer body 10 and is supported by both
the support protrusion 13a and the second outer body 20, and, when
tensile force for pulling the tensioning steel wire 50 is applied
to the tensioning steel wire 50 after the internal fixer has been
installed in the ground, the support protrusion 13a allows the
wedge receiving body 30 along with the wedge unit 40 to be moved
towards the tube coupling hole 11 (that is, to advance
forwards).
[0047] Preferably, the support protrusion 13a protrudes from the
inner surface of the body seating hole 13 to a height ranging from
0.1 mm to 0.5 mm. The reason why the height of the support
protrusion 13a is limited is that, if the protruding height is less
than 0.1 mm, the support protrusion 13a may be easily destroyed
even by a relatively weak tensioning load applied to the tensioning
steel wire 50, and thus the support protrusion 13a cannot conduct
its intended function, and, conversely, if the height to which the
support protrusion 13a protrudes is 0.5 mm or more, because a very
large outer force is required to destroy the support protrusion
13a, a tensioning machine having a large capacity is required and,
as well, when the wedge receiving body 30 is advanced, a large
impact is applied to the first outer body 10, and this impact may
have a bad influence on the internal fixer.
[0048] In this embodiment, the support protrusion 13a, which
protrudes throughout the entire circumference of the
circumferential inner surface of the body seating hole 13 to have a
ring shape and to form an angled and stepped part, is used as the
wedge receiving body support means. Furthermore, the support
protrusion 13a may have a rounded cross-section, a rectangular
cross-section or a trapezoidal cross-section. As well, a plurality
of support protrusions, which are spaced apart from each other on
the circumferential inner surface of the body seating hole 13, may
be used as the wedge receiving body support means. In addition, the
wedge receiving body support means may be realized by a support
protrusion that has two or more steps. In particular, as shown in
FIG. 5, the wedge receiving body support means may be realized by a
tapered inner surface of the body seating hole 13 which is reduced
in diameter from the rear portion to the front portion.
[0049] In addition, the wedge receiving body support means may be
provided only on the circumferential inner surface of the body
seating hole, or, alternatively, may be provided in a combined
manner both on the wedge receiving body and on the circumferential
inner surface of the body seating hole. Hereinafter, examples
thereof will be described.
[0050] FIG. 16 shows at least one support O-ring 14, which is
provided in a ring seating groove 13b in the circumferential inner
surface of a body seating hole 13 so that, when a wedge receiving
body 30 is advanced by pulling the tensioning steel wire 60, the
support O-ring 14, which has supported one end of the wedge
receiving body 30, comes into close contact with and holds the
circumferential outer surface of the wedge receiving body 30.
[0051] FIGS. 7 and 8 show a C-shaped metal ring 15, which
elastically expands in diameter and is provided in a ring seating
groove 13b in the circumferential inner surface of a body seating
hole 13 so that, when a wedge receiving body 30 is advanced by
pulling the tensioning steel wire 60, the C-shaped metal ring 15,
which has supported an end of the wedge receiving body 30, holds
the circumferential outer surface of the wedge receiving body
30.
[0052] FIGS. 9 and 10 show a C-shaped metal ring 15, which
elastically expands in diameter and in the circumferential inner
surface of a body seating hole 13 to temporarily support the end of
a wedge receiving body 30, and show a ring stop groove 32, which is
formed in the circumferential outer surface of the wedge receiving
body 30 such that, when the wedge receiving body 30 is pulled out
by the tensioning steel wire 50, the metal ring 15 is locked to the
ring stop groove 32.
[0053] Furthermore, as shown in FIG. 11, the C-shaped metal ring 15
may be provided in a ring seating groove 33 formed in the
circumferential outer surface of a wedge receiving body 30. In this
case, a ring stop groove 13c must be formed in the circumferential
inner surface of a body seating hole 13.
[0054] As such, in the case that the C-shaped metal ring 15 is used
as the wedge receiving body support means, it suffices if the
C-shaped metal ring 15 has a circular or other cross-section, as
long as the outer surface or inner surface thereof is rounded.
[0055] Meanwhile, a conical wedge seating hole 31, into which the
wedge unit 40 is seated, is formed in the wedge receiving body 30.
The wedge seating hole 31 has a diameter greater than the diameter
of lower ends of separated wedge bodies 41 of the wedge unit 40,
such that, when the separated wedge bodies 41 are seated in the
wedge seating hole 31, the lower ends thereof protrude outside the
wedge seating hole 31.
[0056] Furthermore, the edge of the lower end of the wedge
receiving body 30 that contacts the wedge receiving body support
means is preferably rounded or chamfered, such that, when the
tensioning steel wire 50 is tensioned, the wedge receiving body 30
elastically expands or plastically deforms a single wedge receiving
body support means, which is provided on the inner surface of the
body seating hole 13, or a wedge receiving body support means,
which is provided in a combined manner on the body seating hole 13
and the wedge receiving body 30, so that the wedge receiving body
30 can be easily moved to the bottom of the body seating hole 13.
As well, preferably, the wedge receiving body 30 is made of
material that is processed by heat treatment or has stiffness
higher than that of the first outer body 10.
[0057] The wedge unit 40 is seated in the wedge seating hole 31 of
the wedge receiving body 30. The wedge unit 40 includes the three
separated wedge bodies 41, which are disposed in a circular
arrangement and form a cone shape having a first hole 42, through
which the tensioning steel wire 50 is inserted. Furthermore, an
O-ring 43, which serves to prevent the three separate wedge bodies
41 from being removed and to expand the diameter of lower ends of
the three separate wedge bodies 41, is fitted over circumferential
outer surfaces of upper ends of the three separate wedge bodies 41,
so that they form a single unit. As well, the upper ends of the
three separate wedge bodies 41 are closed such that the tensioning
steel wire 50 is stopped by the upper ends without passing
therethrough and the lower ends of the three separate wedge bodies
41 are expanded in diameter by the O-ring 43.
[0058] The first hole 42 of the wedge unit 40 has an uneven inner
surface, which has a sawtooth or spiral shape. Therefore, when the
tensioning steel wire 50 is tensioned, the uneven inner surface of
the first hole 42 serves to prevent the tensioning steel wire 50
from slipping or being undesirably removed.
[0059] It is sufficient for the second outer body 20 to have a
structure such that the wedge receiving body 30, which is seated in
the body seating hole 13 of the first outer body 10, and the wedge
unit 40, which is seated into the wedge seating hole 31 of the
wedge receiving body 30, can be securely supported without
undesirably moving.
[0060] A steel wire tube 51 is watertightly fitted into the tube
coupling hole 11 of the first outer body 10 without being damaged
at an end thereof such that it does not interfere with insertion of
the tensioning steel wire 50 into the first outer body 10. As well,
the steel wire tube 51 is finished with resin having superior
toughness to prevent it from breaking due to a drop in temperature,
so that it can be used even in the winter. Furthermore, the steel
wire tube 51 prevents water from entering the internal fixer, thus
preventing elements of the internal fixer from rusting.
[0061] The watertight structure of the steel wire tube 51 includes
a reinforcing member 52, which is fitted into the end of the steel
wire tube 51 inserted into the tube coupling hole 11 of the first
outer body 10, and a conical watertight packing member 53, which is
fitted over the end of the steel wire tube 51, into which the
reinforcing member 52 is fitted, and is forcibly fitted into the
tube coupling hole 11 of the first outer body 10.
[0062] Even if the watertight packing member 53 is press-fitted or
struck in a direction from the outside of the steel wire tube 51,
which is inserted into the lower end of the first outer body 10,
towards the center line of the steel wire tube 51, the watertight
packing member 53 must not be broken, but must merely be inserted
while being plastically deformed. Therefore, the watertight packing
member 53 is preferably made of soft resin having superior
ductility and toughness.
[0063] The reinforcing member 52 must be able to prevent a
contraction phenomenon of the steel wire tube 51 in which it is
reduced in diameter by deformation thereof during a process of
forcibly fitting the watertight packing member 53 into the lower
end of the first outer body 10 using the compressing force of
plastic deformation. To achieve the above-mentioned purpose, it is
preferable that the reinforcing member 52 be made of metal or high
stiffness material, such as compressed fiber and high stiffness
resin.
[0064] The assembly of the internal fixer of the present invention
having the above-mentioned construction will be explained herein
below. The steel wire tube 51 is first inserted into and coupled to
the tube coupling hole 11 of the first outer body 10. Here, after
the reinforcing member 52 has been fitted into the end of the steel
wire tube 51 and the conical watertight packing member 53 has been
fitted over the end of the steel wire tube 51, the end of the steel
wire tube 51 is inserted into the tube coupling hole 11 of the
first outer body 10. Thereafter, the watertight packing member 53
is press-fitted into the tube coupling hole 11. Then, the steel
wire tube 51 is securely watertightly fitted into and coupled to
the first outer body 10 without being damaged at the end
thereof.
[0065] In this state, the tensioning steel wire 50 is inserted into
the steel wire tube 51, such that the end thereof passes through
the body seating hole 13 of the first outer body 10 and passes
through and protrudes outside the wedge receiving body 30, which is
temporarily seated in the body seating hole 13. Subsequently, the
end of the tensioning steel wire 50 is maximally inserted into the
first hole 42 in the wedge unit 40, which is constructed by
assembling the three separated wedge bodies 41 with each other
using the O-ring 43 such that they are separated in the diameter
direction at the lower ends thereof by the O-ring 43. Thereafter,
in the state in which the separated wedge bodies 41 are closed to
hold the tensioning steel wire 50, the wedge unit 40 is inserted
into the wedge seating hole 31 of the wedge receiving body 30 and,
thereafter, the second outer body 20 is coupled to the first outer
body 10.
[0066] When the second outer body 20 is coupled to the first outer
body 10, the second outer body 20 pushes the wedge receiving body
30 and the separated wedge bodies 41 of the wedge unit 40, which is
placed in the wedge seating hole 31 of the wedge receiving body 30.
Therefore, the wedge receiving body 30 is seated onto the support
protrusion 13a of the wedge receiving body support means, and the
tensioning steel wire 50 is held by the separated wedge bodies 41
more securely.
[0067] The internal fixer, which has been assembled through the
above-mentioned process, is installed in the ground. First, a
braced wall is constructed to prevent a cut slope, such as a
retaining wall, requiring ground reinforcement, from collapsing. In
consideration of the ground reinforcement using anchors, holes are
bored downwards at an incline in the ground to predetermined depths
using a boring machine at positions spaced apart from each other at
regular intervals. Thereafter, a grout hose and a load-carrying
body, which includes the tensioning steel wire and the internal
fixer, are inserted into each boring hole, and grout is injected
through the grout hose. After the injected grout cures with the
load-carrying body, an external fixer is coupled to the other end
of the tensioning steel wire, which is adjacent to the braced
wall.
[0068] In this state, the tensioning steel wire is pulled by a
tensioning machine, so that the grout and ground are tensioned,
thus reinforcing the soft ground. This will be explained in detail
with reference to FIGS. 1 and 3.
[0069] When the tensioning steel wire is pulled at a position
adjacent to the braced wall, the tensile force of the tensioning
machine is transmitted to the wedge receiving body 30 through the
wedge unit 40. Thus, the wedge receiving body 30 along with the
wedge unit 40 is advanced after breaking the support protrusion
13a, which is provided on the inner surface of the body seating
hole 13 of the first outer body 10, until the wedge receiving body
30 reaches the bottom of the body seating hole 13 of the first
outer body 10, that is, until it changes from the state of FIG. 1
to that of FIG. 3. At this time, because the wedge unit 40 is in a
state of being tensioned by the tensioning steel wire 50, the wedge
receiving body 30 maintains the state of being seated in the wedge
seating hole 31. Therefore, the separated wedge bodies 41 of the
wedge unit 40 reliably hold the tensioning steel wire 50.
[0070] As such, when the wedge receiving body 30 is advanced until
it reaches the bottom of the body seating hole 13 of the first
outer body 10, the wedge receiving body 30 is securely fastened to
the body seating hole 13 of the first outer body 10 by the broken
support protrusion 13a, which has been provided on the inner
surface of the body seating hole 13 of the first outer body 10, as
if it were processed by being integrated or press-fit.
[0071] Continuously, as the tensioning machine more strongly pulls
the tensioning steel wire 50, increased tensile force is applied to
the grout, the ground and the tensioning steel wire 50. Meanwhile,
after the ground reinforcing work has been completed, the
tensioning steel wire 50 must be removed.
[0072] In the process of removing the tensioning steel wire 50, the
part of the tensioning steel wire 50 exposed outside at a side
adjacent to the braced wall is first cut using an oxygen cutting
machine to remove the tensile force, which has been applied to the
tensioning steel wire 50. At this time, in the state in which the
wedge receiving body 30 is fastened in the body seating hole 13 of
the first outer body 10, the wedge unit 40 may be slightly moved
backwards by repulsive force generated when removing the tensile
force from the tensioning steel wire 50.
[0073] Thereafter, the cut end of the tensioning steel wire 50,
part of which is installed in the ground, is struck with a hammer
one or two times. Then, as shown in FIG. 4, only the wedge unit 40
is moved backwards by the force of striking the tensioning steel
wire 50, and the separated wedge bodies 41 are separated in the
diameter direction by the O-ring 43. Therefore, the tensioning
steel wire 50 is released from the separated wedge bodies 41 of the
wedge unit 40.
[0074] As such, the reason why the wedge unit 40 can be moved
backwards is that, when the tensioning steel wire 50 is tensioned,
a space is defined behind the wedge unit 40 by movement of the
wedge receiving body 30 and the wedge unit 40 to the bottom of the
body seating hole 13 of the first outer body 10.
[0075] As such, after the tensioning steel wire 50 has been
released from the wedge unit 40, because the only resistance is its
own weight and a little frictional resistance, the tensioning steel
wire 50 can be easily removed by pulling it.
[0076] FIG. 12 is a sectional view showing an internal fixer for an
anchor having a releasable tensioning steel wire, a wedge returning
means being provided for a wedge unit, according to another
embodiment of the present invention. In the wedge returning means,
a spring seating hole 17 is formed in the bottom of a body seating
hole 13 of a first outer body 10, and a wedge returning member 60
is provided in the spring seating hole 17, such that, when the
tensioning steel wire 60 is tensioned so that a wedge receiving
body 30 is advanced into and fastened into a body seating hole 13,
ends of separated wedge bodies 41 of the wedge unit 40 which
protrude from the wedge seating hole 31 of the wedge receiving body
30 are biased backwards by the wedge returning member 60.
[0077] The wedge returning member 60 is not limited to any
particular structure, so long as it can push the end of the wedge
unit 40 backwards and can be inserted into the wedge seating hole
31 of the wedge receiving body 30. Preferably, a compression coil
spring is used as the wedge returning member 60. The shape of the
compression coil spring may be changed depending on the size of the
spring seating hole 17.
[0078] For example, in the case that the diameter of the spring
seating hole 17 is about twice that of the tensioning steel wire,
it is preferable that a conical compression coil spring be used. In
the case that the spring seating hole 17 has a relatively small
diameter similar to that of the wedge seating hole 31, it is
preferable that a cylindrical compression coil spring be used.
[0079] As described above, in the case that the wedge returning
member 60 is provided in the internal fixer of the present
invention, in a process of removing the tensioning steel wire 50
after the ground reinforcing work has been completed, when the part
of the tensioning steel wire 50 that is exposed outside at the side
adjacent to the braced wall is cut using an oxygen cutting machine
to remove the tensile force, which has been applied to the
tensioning steel wire 50, the wedge unit 40 is easily moved
backwards both by repulsive force, which is generated upon removal
of the tensile force of the tensioning steel wire 50 in the state
in which the wedge receiving body 30 is fastened in the body
seating hole 13 of the first outer body 10, and by restoring force
of the compression coil spring, which is the wedge returning member
60, as shown from FIG. 13 to FIG. 14.
[0080] Here, even if the wedge unit 40 is not moved backwards for
some reason such as corrosion of the wedge receiving body 30 and
the wedge unit 40, when the cut end of the tensioning steel wire
50, part of which is installed in the ground, is struck with a
hammer one or two times, as shown in FIG. 15, the wedge unit 40 can
be moved backwards both by the force of striking the tensioning
steel wire 50 and by the restoring force of the compression coil
spring, which is the wedge returning member 60.
[0081] As such, when the wedge unit 40 is moved backwards so that
the separated wedge bodies 41 are separated in the diameter
direction by an O-ring 43, the tensioning steel wire 50 is released
from the separated wedge bodies 41 of the wedge unit 40. Therefore,
the tensioning steel wire 50 can be easily removed by pulling
it.
[0082] Meanwhile, as shown in FIG. 16, the wedge returning member
60 may consist of a support ring member 61, which supports the ends
of the separated wedge bodies 41 and has a flange on an end
thereof, and a compression coil spring 62, which has a cylindrical
shape and pushes the support ring member 41 backwards.
[0083] FIG. 17 illustrates an internal fixer for an anchor having a
releasable tensioning steel wire, a wedge support means being
provided for a wedge unit, according to another embodiment of the
present invention. In this embodiment, the second outer body 20 has
a length sufficient to define a space for ensuring backward
movement of a wedge unit 40. An elastic support member 70, which
pushes and seats the wedge unit 40 into a wedge seating hole 31 of
a wedge receiving body 30, is installed in the space defined in the
second outer body 20. The elastic support member 70 is not limited
to any particular structure, so long as it elastically and reliably
supports the wedge unit 40. Preferably, a cylindrical or conical
compression coil spring, which is freely available, is used as the
elastic support member 70.
[0084] To assemble this embodiment having the above-mentioned
construction, the wedge receiving body 30 along with the wedge unit
40 is seated into a body seating hole 13 of a first outer body 10.
Thereafter, the second outer body 20 is coupled to the first outer
body 10 after the elastic support member 70 has been installed in
the second outer body 20. Then, the wedge unit 40 is elastically
supported by the elastic support member 70.
[0085] Furthermore, to assemble the tensioning steel wire 50, the
tensioning steel wire 50 is inserted into a steel wire tube 51,
which is fitted into a tube coupling hole 11 of the first outer
body 10. Then, the wedge unit 40 is moved backwards from the wedge
receiving body 30 by the tensioning steel wire 50 in the state of
being elastically supported by the elastic support member 70, so
that the separated wedge bodies 41 of the wedge unit 40 are
separated in the diameter direction by an O-ring 43 while an end of
the tensioning steel wire 50 is inserted into the separated wedge
bodies 41.
[0086] Thereafter, when force, which has been applied to the
tensioning steel wire 50, is removed in the state in which the
tensioning steel wire 50 is inserted into the separated wedge
bodies 41, the separated wedge bodies 41 are inserted into the
wedge seating hole 31 of the wedge receiving body 30 by the
restoring force of the elastic support member 70. At this time, the
tensioning steel wire 50 is reliably held by the separated wedge
bodies 41. As such, the assembly of the tensioning steel wire 50
can be more easily conducted.
[0087] FIG. 18 illustrates an internal fixer for an anchor having a
releasable tensioning steel wire, a wedge support means being
provided for a wedge unit, according to another embodiment of the
present invention. In this embodiment, an inner ring groove 43 is
formed in an upper end of a first hole 42 defined by separated
wedge bodies 41. A cap member 45, which is provided with a flange
and has a cap-shaped cross-section, is coupled to the inner ring
groove 43 and protrudes from the upper end of the first hole 42
without interfering with the diameter expanding motion of the
separated wedge bodies 41. Even in this case, in which the cap
member 45 protrudes from the upper end of the separated wedge
bodies 41, an elastic support member 70, which pushes and seats the
wedge unit 40 into a wedge seating hole 31 of a wedge receiving
body 30, is provided in the second outer body 20. Although the
wedge support means has been explained as having only a structure
such that the cap member 45 is coupled to the inner ring groove 43
of the wedge unit 40, a circular plate may be additionally
provided.
[0088] According to this embodiment having the above-mentioned
construction, because the elastic support member 70, which
comprises the cylindrical or conical compression coil spring, is
seated onto the wedge unit 40 and fitted over the outer surface of
the cap member 45, which protrudes from the wedge unit 40,
operational precision is ensured without the elastic support member
70 being misaligned or undesirably moving.
[0089] Particularly, the end of the tensioning steel wire 50, which
is inserted through a tube coupling hole 11 of the first outer body
10, is disposed in the cap member 45 via the separated wedge bodies
41. Thus, the tensioning steel wire 50 is reliably held by the
separated wedge bodies 41. Furthermore, because the separated wedge
bodies 41 hold the tensioning steel wire 50 more strongly, the
tensioning steel wire 50, which is formed by twisting several
wires, may be untwisted at a part thereof that is in the cap member
45, so that the diameter of that part of the tensioning steel wire
50 is slightly increased. Therefore, the tensioning steel wire 50
can be more securely held, as if a stop protrusion were formed on
the tensioning steel wire 50.
[0090] Furthermore, as shown in FIG. 19, a compression cover 71 may
is seated on the separated wedge bodies 41 outside the cap member
45 between the separated wedge bodies 41 and the elastic support
member 70. The compression cover 71 prevents interference between
the separated wedge bodies 41 and the elastic support member 70 and
makes it possible for the separated wedge bodies 41 to be reliably
separated in the diameter direction when being moved away from the
wedge seating hole 31 of the wedge receiving body 30 during a
process of assembling the tensioning steel wire 50, thus making the
assembly of the tensioning steel wire 50 rapid and precise.
INDUSTRIAL APPLICABILITY
[0091] As described above, an internal fixer for an anchor having a
releasable tensioning steel wire according to the present invention
can be efficiently used in engineering work, in which holes are
bored at a predetermined position in soft ground using a boring
machine, a grout hose and a load-carrying body, which includes the
tensioning steel wire and the internal fixer, are inserted into the
boring hole, grout is injected through the grout hose, the injected
grout cures with the load-carrying body, an external fixer is
coupled to the other end of the tensioning steel wire, and the
tensioning steel wire is pulled by a tensioning machine so that the
grout and ground are tensioned, thus reinforcing the soft ground.
That is, the present invention can be used in engineering work such
as bracing work and engineering work for stabilizing a tunnel
portal or for reinforcing a stone wall or a retaining wall.
* * * * *