JP2011074578A - Ground anchor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ground anchor improved in durability in the inclined state without an adverse effect in maintaining the tensile force of the ground anchor even in the inclined state in the ground. <P>SOLUTION: The ground anchor includes a bearing plate located in an anchor hole excavated in the ground, and a tensile force introducing member penetrating the bearing plate so that one end is anchored through an anchor hole side anchor part below the bearing plate while the other end is anchored through a foundation side anchor part on a structure foundation constructed on the ground. The ground anchor further includes a hole inside elastic body inserted between the anchor hole side anchor part and the bearing plate, and a foundation side elastic body inserted between the foundation side anchor part and the structure foundation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a ground anchor, and more particularly to a ground anchor that prevents the influence of an earthquake, groundwater, or the like.

Conventionally, as a method of firmly fixing the foundation of a structure such as a building or house to the ground, a ground anchor having a length that can penetrate the structure foundation and reaching the inside of a hole formed in the ground is installed. After that, the concrete of the foundation of the structure is placed on the part exposed from the ground, and tension is applied to the tension introduction material inserted into the ground anchor by the tension introduction tool on the foundation of the structure. By transmitting force to the ground, a method is adopted that prevents the foundation of the structure from being lifted due to earthquakes or groundwater fluctuations. The ground anchor generally penetrates the upper bearing plate provided on the structure foundation and extends to the inside of the hole, and the lower side fixed to the ground side tip of the tension introducing material in the hole It consists of a bearing plate and a load-bearing body that comes into contact with the upper surface of the lower bearing plate. After injecting an injection material such as cement milk into the hole and solidifying the injection material, tension is applied to the tension-introducing material on the structure foundation. By applying a force, the reaction force is transmitted to the ground via a bearing plate, a load bearing body and an injection material existing in the hole.
It is known that the tension force of the ground anchor having the above structure decreases with time due to fluctuations caused by the load of the structure built on the structure foundation, the relaxation of the tension introduction material itself, etc. The tension force of the ground anchor is reduced by inserting a spring body between the upper bearing plate and the surface of the structure for the purpose of compensating for the reduction of the mechanical tension force, and the reaction force acting as the spring body contracts There is known a ground anchor having a structure for reducing the vibration.

Japanese Patent Laid-Open No. 11-43941

  However, in general, in the construction of ground anchors, there are many cases where a plurality of ground anchors are installed in a limited space in the foundation plane of the structure. It is difficult to install perpendicular to the foundation surface. Even if it can be installed vertically at the beginning, it may be installed in a tilted state due to the horizontal force or horizontal fluctuation of the ground due to the earthquake, and the conventional ground that inserts a spring body on the structure foundation When the anchor is tilted, the reaction force of the spring body is not transmitted along the axial direction of the tension introducing material, and an extra force (shearing force, rotational force, etc.) is applied to the place where the tension of the ground anchor is maintained There arises a problem that tension cannot be maintained due to deformation or breakage of the portion.

  Therefore, in order to solve the above-described problems, the present invention provides a ground anchor that does not adversely affect the tension of the ground anchor even when tilted in the ground, and has improved durability in the tilted state. The purpose is to provide.

In order to solve the above-mentioned problem, as a first configuration according to the present invention, a bearing plate located in a fixing hole excavated in the ground, and a fixing hole side penetrating the supporting plate and having one end below the supporting plate. A ground anchor comprising a tension-introducing material fixed to the ground via a fixing part and fixed to the ground via a foundation-side fixing part on a foundation of a structure constructed on the ground, the other end of the ground anchor, A hole inner elastic body inserted between the fixing hole side fixing section and the pressure bearing plate, and a base side elastic body inserted between the base side fixing section and the structure foundation are provided.
According to this configuration, even if the tension-introducing material is inclined and installed in the ground, the elastic body located on the structure foundation side and the elastic body located in the ground hole are tensioned. Since the material is deformed corresponding to the inclination of the introduction material, the reaction force due to the compression of the elastic body can be transmitted along the axial direction of the tension force introduction material. Furthermore, since excessive shear force can be prevented from being applied to the tension-introducing material, durability is improved.
Further, as a second configuration according to the present invention, a plurality of the tension force introduction materials are provided, and the hole inner elastic body and the base side elastic body are inserted for each of the plurality of tension force introduction materials.
According to this configuration, when a plurality of tension introduction materials are used, even if each of the tension introduction materials has different inclinations, the hole inner elastic body and the base side elastic body are one. Since the elastic body is individually inserted so as to correspond to the tension force introducing material, the elastic body deforms corresponding to the inclination of each tension force introducing material, and the reaction force due to the compression of the elastic body is converted to the axis of the tension force introducing material. It is possible to transmit along the direction.
Further, as a third configuration according to the present invention, a plurality of bearing plates are arranged along the extending direction of the fixing hole, and between the plurality of bearing plates and between the bearing plate and the structure foundation. It was set as the structure provided with the load-bearing body which touches.
According to this configuration, since a plurality of transmission portions can be formed by a plurality of bearing plates and a load bearing body corresponding to each of the bearing plates, a plurality of reaction forces against the tension force applied to the tension force introducing member are transmitted. It is possible to distribute to the ground and transmit to the ground. Furthermore, the strength and cross-sectional dimensions of one load-bearing body itself can be set small, and the anchor can be downsized.
The summary of the invention does not enumerate all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention. Hereinafter, the present invention will be described in detail through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are included. It is not necessarily essential to the solution means of the invention, and includes a configuration or process that is selectively adopted.

It is a schematic sectional drawing of the ground anchor 1 which concerns on this invention. It is sectional drawing of the base 7 and the bearing plate 8. FIG. It is sectional drawing of the upper side pressure plate 17 and the lower side pressure plate. It is the schematic diagram which used PC steel material 6A as an example. It is a model which shows a deformation | transformation of the base side elastic body 9 and the hole inner side elastic body 22A.

FIG. 1 is a schematic sectional view of a ground anchor 1 according to the present invention.
In the figure, the ground anchor 1 is composed of an injection material 5 such as cement milk around the ground anchor 1 in a fixing hole 4 excavated in the ground 3 to be constructed of a structural foundation 2 constructed of, for example, reinforced concrete. It is fixedly installed by being injected so as to surround it.
The ground anchor 1 includes a head L1 exposed on the structure foundation 2 in a state of being installed in the fixing hole 4, a free length portion L2 that passes through the structure foundation 2 and extends to the fixing hole 4, and a free length. The transmission portion L3 extends from the lower end of the portion L2 to the vicinity of the bottom portion 4A of the fixing hole 4 and transmits a reaction force against the tension applied to the tension introduction material to the ground 3. The ground anchor 1 includes a plurality of PC steel materials 6A; 6B having different lengths as tension introduction materials that extend in the vertical direction across the head L1, the free length portion L2, and the transmission portion L3. A mechanism for transmitting reaction force to the ground 3 with respect to 6B is attached. Details of each part will be described below.

The head L1 includes a pedestal 7, a support plate 8 positioned above the pedestal 7, a base-side elastic body 9 interposed between the pedestal 7 and the support plate 8, and the upper surface of the support plate 8, that is, the structure. It is comprised from the foundation side fixing | fixed part 10 located above the object foundation 2, and the head cap 11 put on the bearing plate 8.
The pedestal 7 is, for example, a circular plate-shaped steel material that is fixed integrally with the concrete that is placed when the structure foundation 2 is constructed and is positioned on the surface of the structure foundation 2 after the concrete is solidified, and is a PC steel material. A plurality of through holes 12 corresponding to the number of 6A; 6B are formed. The remaining portion of the PC steel 6A; 6B exposed on the structure foundation 2 is inserted into the through hole 12. In addition, the hole diameter of the through-hole 12 is larger than the diameter of PC steel material 6A; 6B, and is a hole diameter which accept | permits tilting of PC steel material 6A; 6B.
The support plate 8 is a circular plate-shaped steel material that is positioned above the pedestal 7 by inserting a below-described foundation side elastic body 9, and the through-hole 12 is located at a position corresponding to the through-hole 12 of the pedestal 7. A through hole 13 having the same hole diameter is formed. Similar to the base 7, the remaining portions of the PC steel materials 6 </ b> A and 6 </ b> B exposed to the structure base 2 side are inserted into the through holes 13.

FIG. 2 is a cross-sectional view of the pedestal 7 and the bearing plate 8, and the pedestal 7 and the bearing plate 8 are different only in diameter. In the figure, the through-holes 12 (through-holes 13) only need to be concentric circles, and in this embodiment, the through-holes 12 (through-holes 13) are opened at 90 ° intervals on the circumference. The PC steel materials 6A; 6B are inserted alternately. In addition, a through hole 7 a is opened at the center of the base 7. The through hole 7a is an injection hole for the rust preventive oil 30 injected into the free top portion L2 and the transmission portion L3, and the rust preventive oil 30 is injected directly from the through hole 7a or by inserting a hose. .
In addition, in this embodiment, although the tension | tensile_strength introduction material was comprised by making two PC steel materials 6A and two PC steel materials 6B shorter than PC steel materials 6A as one set, the number of tension force introduction materials is set to this. The number of ground anchors 1 that can be installed on the structure foundation 2 and the magnitude of tension to be introduced can be appropriately changed.

The base side fixing unit 10 is a member fixed to the upper surface of the bearing plate 8, and a plurality of fixing holes are formed at positions corresponding to the base 7 and the through holes 12; 13 of the bearing plate 8.
The ends of the PC steel materials 6A; 6B are inserted into the plurality of fixing holes, and a wedge 15 is driven into the fixing holes in a state in which a predetermined tension, for example, about 1000 kN is introduced into the PC steel materials 6A; 6B. As a result, the PC steel materials 6A and 6B are fixed to the base side fixing portion 10 while maintaining the tension state.

The base side elastic body 9 is a member inserted between the pedestal 7 and the bearing plate 8, and the PC steel materials 6 </ b> A and 6 </ b> B are inserted therein. As the base-side elastic body 9, for example, a laminated disc spring, a leaf spring, a rubber body, or the like is employed in addition to the compression coil spring illustrated. In other words, any member can be used as long as it can generate a reaction force against the contraction of the spring accompanying the decrease in the tension of the PC steel materials 6A and 6B. Thus, the base side elastic body 9 is inserted between the base 7 and the bearing plate 8, thereby reducing the tension force caused by the relaxation of the PC steel materials 6 </ b>A; It is possible to always compensate by force.
Further, without providing the pedestal 7 on the structure foundation 2, a structure in which the foundation-side elastic body 9 is interposed between the surface of the structure foundation 2 and the bearing plate 8, or the bearing plate 8 and the foundation-side fixing unit 10. The same effect as described above can be obtained even when the base-side elastic body 9 is interposed between the two. That is, the position of the base-side elastic body 9 is not limited as long as it exists below the lower surface of the base-side fixing unit 10 and above the surface of the structure base 2.
The head cap 11 is a cylindrical body with one opening fixed to the upper surface of the base 7 via a fixing tool such as a bolt, and includes a base-side elastic body 9, a bearing plate 8, a base-side fixing unit 10, a wedge 15, and It covers the ends of the PC steel 6A; 6B and protects the head L1. The antirust oil 30 is injected into the internal space of the head cap 11 through an injection hole (not shown), and the inside of the head cap 11 is brought into a liquid-tight state by the antirust oil 30.

  The free length portion L <b> 2 is configured by a sheath tube 16 that extends from the lower surface of the base 7 to the vicinity of the upper end portion of the fixing hole 4. The sheath tube 16 is a cylindrical member that is open at both ends, and has an upper end connected to the lower surface of the pedestal 7 and a lower end connected to an upper load bearing body 19 described later. The connection is realized by screw connection, fitting connection, or welding with the base 7 or the upper load-bearing body 19. Further, the dimension of the free length portion L2 is not limited to the illustrated example, and can be set as appropriate depending on the thickness of the structure base 2 in the vertical direction and the depth of the fixing hole 4.

  The transmission portion L3 includes an upper bearing plate 17 and a lower bearing plate 18 that are spaced apart in the vertical direction along the extending direction of the fixing hole 4, and upper sides corresponding to the upper bearing plate 17 and the lower bearing plate 18, respectively. A fixing hole side fixing portion for fixing the load bearing body 19 and the lower load bearing body 20 and the upper bearing plate 17 and the lower bearing plate 18 to the PC steel 6A; 6B below the upper bearing plate 17 and the lower bearing plate 18. 21A; 21B, a hole inner elastic body 22A provided corresponding to the fixing hole side fixing section 21A, a hole inner elastic body 22B provided corresponding to the fixing hole side fixing section 21B, and a tip cap 23. Is done. Hereinafter, the transmission unit L3 will be described in detail.

As shown in FIG. 3A, the upper support plate 17 is a circular steel plate, and has a plurality of through holes 23a to 23d arranged at equal intervals along the circumferential direction, like the base 7 and the support plate 8. Have. The PC steel materials 6A; 6A are inserted into the through holes 23a; 23c of the upper bearing plate 17, respectively, and the PC steel materials 6B; 6B are inserted into the through holes 23b; The through holes 23a to 23d have the same diameter as that of the through hole 12 described above.
As shown in FIG. 3 (b), the lower support plate 18 is a circular steel plate having the same shape as the upper support plate 17 and has through holes 23e; 23f at positions corresponding to the through holes 23a; 23c. . The PC steel materials 6A and 6A are inserted through the through holes 23e and 23f, respectively.

The upper bearing plate 17 is positioned slightly above the center of the entire length of the fixing hole 4, and is connected to the upper load-bearing body 19 so that the peripheral edge and the side face the lower end portion 19 b of the upper load-bearing body 19.
The lower bearing plate 18 is positioned below the upper bearing plate 17 and above the bottom 4A of the fixing hole 4 and is connected to the lower load bearing member 20 so that the periphery and side surfaces thereof are located on the lower side. It contacts the lower end 20b of the load-bearing body 20.
A tip cap 23 is connected to the lower surface of the lower support plate 18 to protect the entire PC steel 6A protruding downward from the lower support plate 18.

The upper load-bearing body 19 is a steel pipe having openings at both ends provided with a plurality of protrusions that increase the adhesion force and frictional force to the injection material 5 on the peripheral surface in contact with the injection material 5, and the upper end portion 19 a is the lower end portion of the sheath tube 16. By being connected to 16 a, the peripheral edge and the side face abut on the lower end portion 16 a of the sheath tube 16. That is, the upper load bearing member 19 is a member located between the upper bearing plate 17 and the structure foundation 2, more specifically, between the sheath tube 16 and the upper bearing plate 17.
The lower load bearing body 20 is a steel pipe having both ends opened in the same shape as that of the upper load bearing body 19, and the upper end 20 a is connected to the lower end of the upper bearing plate 17, so that the periphery and side surfaces thereof are the upper bearing plate 17. It contacts the lower end of the. That is, the lower load bearing member 20 is a member positioned between the upper bearing plate 17 and the lower bearing plate 18.

  In this way, the sheath tube 16, the upper bearing plate 17, the lower bearing plate 18, the upper load bearing body 19, the lower load bearing body 20, and the tip cap 23 are connected to each other, so that the structure foundation 2 A hollow cylindrical body extending from the vicinity of the surface to the vicinity of the bottom 4A of the fixing hole 4 is formed. Further, the hollow portion is filled with a rust preventive oil 30 for protecting the PC steel materials 6A and 6B existing inside.

The PC steel 6A; 6A inserted into the through holes 23a; 23c of the upper bearing plate 17 and the through holes 23e; 23f of the lower bearing plate 18 is below the lower surface of the lower bearing plate 18 and from the lower end surface of the tip cap 23. Is also fixed at the fixing hole side fixing portion 21 </ b> A below the lower support plate 18. For example, a fixing tool called a crimping grip is used for the fixing hole side fixing portion 21A, and the lower end portion of the PC steel material 6A is firmly fixed so as not to come out from the through holes 23e; 23f of the lower support plate 18.
A hole inner elastic body 22A is interposed between the lower surface of the lower support plate 18 and the upper surface of the fixing hole side fixing portion 21A. The hole inner elastic body 22A is a member having the same structure as the base elastic body 9, and the remaining portion of the PC steel 6A; 6A protruding from the lower surface of the lower support plate 18 is inserted into the hole inner elastic body 22A. That is, the foundation side elastic body 9 located on the structure foundation 2 side and the hole inner elastic body 22A located in the fixing hole 4 are PC steel materials as a pair of upper and lower elastic bodies corresponding to one PC steel material 6A. It is a member inserted every 6A.

The PC steel materials 6B and 6B inserted through the through holes 23b and 23d of the upper bearing plate 17 terminate below the lower surface of the upper bearing plate 17 and above the upper end surface of the lower bearing plate 18, and Fixing is performed by the fixing hole side fixing unit 21B below. The fixing hole side fixing portion 21B employs a crimping grip as described above, and firmly fixes the lower end portion of the PC steel material 6B so as not to come out from the through holes 23b; 23d of the upper bearing plate 17.
A hole inner elastic body 22B is interposed between the lower surface of the upper support plate 17 and the upper surface of the fixing hole side fixing portion 21B. The hole inner elastic body 22B is the same member as the hole inner elastic body 22A, and the remaining portion of the PC steel material 6B; 6B protruding from the lower surface of the upper bearing plate 17 is inserted into the hole inner elastic body 22B. That is, the base side elastic body 9 positioned on the structure base 2 side and the hole inner side elastic body 22B positioned in the fixing hole 4 are PC steel materials 6B as a pair of upper and lower elastic bodies corresponding to one PC steel material 6B. It is a member inserted every time.

In this way, the lower support plate 18 and the lower load bearing body 20 that contacts the lower support plate 18 form a first-stage transmission portion, and the lower end portion of the PC steel 6A; 6A is connected to the lower support plate 18. In the lower part, fixing is performed by the fixing hole side fixing section 21A, and the second stage transmission section is formed by the upper bearing plate 17 and the upper load bearing body 19 in contact with the upper bearing plate 17, and the PC steel materials 6B; After fixing the lower end portion below the upper support plate 17 by the fixing hole side fixing portion 21B, a tension force is introduced into the PC steel materials 6A; 6B, and the upper end portion of the PC steel materials 6A; By firmly fixing, the reaction force generated in the PC steel 6A; 6B due to the introduction of the tension force causes the upper bearing plate 17 and the lower bearing plate 18, the upper load bearing body 19 and the lower load bearing body 20, and the injection material surrounding them. 5 to the ground 3 via And thus.
In this example, the upper load bearing body 19 and the lower load bearing body 20 are configured to have a two-stage transmission portion L3 to disperse the tension force borne by one load bearing body. For example, a one-stage configuration may be used, or a three-stage or more configuration may be used. In the case of a single-stage configuration, the upper bearing plate 17 and the upper load bearing member 19 shown in FIG. 1 are eliminated, and a single load bearing member extending from the upper end portion of the lower bearing plate 18 to the lower end portion 16a of the sheath tube 16 is provided. The body may be adopted, and in the case of a configuration of three or more stages, a plurality of transmission parts are constituted by a plurality of pressure plates and a plurality of load-resistant bodies corresponding to the pressure plates, and the PC reaches a length that reaches each pressure plate. The steel material may be fixed below the lower surface of each bearing plate.

FIGS. 4 and 5 are schematic views illustrating the PC steel material 6A as an example, and models showing the deformation of the base-side elastic body 9 and the hole-side elastic body 22A, respectively. On the other hand, the operation and effect of the presence of the base side elastic body 9 and the hole inner elastic body 22A which are provided apart in the vertical direction will be described in detail. Although the PC steel material 6A is taken as an example in explaining the operation and effect, the same operation and effect can be obtained when the base side elastic body 9 and the hole inner elastic body 22B are provided in the PC steel material 6B.
FIG. 4 is a schematic diagram in the case where a horizontal displacement occurs between the structure foundation 2 and the ground 3 due to the force P acting on the ground 3 due to an earthquake, for example. The horizontal bearing plate 8 and the lower bearing plate 18 of the ground anchor 1 are relatively displaced in the horizontal direction, and the axis perpendicular to the surface of the structural foundation 2 of the PC steel 6A is angle α from the state of O. It will be in the state inclined to the position of shifted O '.
And in such a case, between the base side elastic body 9, the fixing hole side fixing part 21A, and the lower side pressure plate 18 inserted between the pedestal 7 fixed to the structure foundation 2 and the pressure plate 8. When the inserted hole inner elastic body 22A is deformed corresponding to the inclination, the PC steel 6A is always kept in a straight line over the entire length.
Specifically, as shown in the partially enlarged view of FIG. 4, the base-side elastic body 9 and the hole-side elastic body 22A correspond to the deviation angle α of the PC steel material 6A, that is, the base-side elastic body 9 is the top. The end surface is inclined with respect to the lower end surface by the shift angle α of the PC steel material 6A. In the hole inner elastic body 22A, the lower end surface is inclined with respect to the upper end surface by the shift angle α of the PC steel material 6A. Is kept straight.
That is, by providing the base side elastic body 9 and the hole inner side elastic body 22A to the PC steel material 6A as the anchor, the PC steel material 6A extends over the entire length even when an external force is applied between the structure foundation 2 and the ground 3. The tension applied to the PC steel 6A always acts in the axial direction of the PC steel 6A, and the remainder of the PC steel 6A fixed by the base-side fixing part 10 and the wedge 15 is maintained. The shearing force does not act between the portion, the main body portion, and the remaining portion of the PC steel material 6A fixed to the fixing hole side fixing portion 21A and the main body portion.

As shown in FIG. 5, when an instantaneous force acts on the structure foundation 2 and the ground 3 due to an earthquake or the like in an anchor in which the foundation-side elastic body 9 is interposed only in one of the fixed portions A of the PC steel 6A, Since the PC steel material 6A is inclined at the angle α starting from the fixed portion B, the distance L4 from the fixed portion A to the fixed point B is shortened by δL. The reaction force of the base side elastic body 9 contracting by δL is applied to the PC steel material 6A and becomes a tension force T2 larger than the original tension force T1, but the tension force T2 is a normal force at the fulcrum B at this time. The decomposed force acts on T3 and the horizontal force T4, the horizontal force acts as a shearing force on the PC steel 6A in the vicinity of the fulcrum B, and the PC steel 6A buckles or deforms and breaks to cause the PC steel 6A. There is a risk that the lifetime of
However, by providing the base side elastic body 9 and the hole inner elastic body 22A to the PC steel material 6A as described above, it is possible to always apply the tension force in the axial direction of the PC steel material 6A, and to the PC steel material 6A. On the other hand, since an excessive shearing force is not applied, it is possible to obtain a ground anchor 1 that maintains a constant tension as an anchor over a long period of time and sufficiently secures durability as a device.

Hereinafter, the installation method of the ground anchor 1 which consists of the said structure is demonstrated.
First, the fixing hole 4 is excavated while injecting water into the ground 3 by an excavating machine called a double casing. Thereafter, the ground anchor 1 assembled on the ground is built in the fixing hole 4. In that state, the injection material 5 such as cement milk is injected while being pressurized, and by replacing the water inside while injecting the injection material 5 into the wall surface where the fixing hole 4 is formed, part of the free length L2 and transmission The portion L3 is fixed to the fixing hole 4 of the ground 3. The injecting material 5 permeates the wall surface of the fixing hole 4 to improve the frictional force between the injecting material 5 and the wall surface. Thereafter, the pedestal 7 is temporarily fixed at a predetermined position of the PC steel 6A; 6B. The temporary fixing process is performed by using a non-illustrated reinforcing bar arranged in advance when the structure foundation 2 is constructed. Then, concrete is placed so as to cover the sheath tube 16 exposed from the ground 3, and the remaining portion of the free length portion L <b> 2 is fixed to the structure foundation 2.
Next, the rust preventive oil 30 is injected into the free length portion L2 and the transmission portion L3 configured as a cylindrical body, and the PC steel materials 6A; The assembly process of the head L1 is performed on the remaining part. Specifically, the base side elastic body 9 is individually inserted from the upper end side of the PC steel 6A; 6B, and the base side elastic body 9 is placed on the base 7. After that, by placing the support plate 8 on the base side elastic body 9 so as to pass through the through hole 13 from the upper end side of the PC steel 6A; 6B, the base side elastic body 9 is placed between the base 7 and the support plate 8. It is assumed that it is inserted between them.
Next, the base side fixing part 10 is passed through the plurality of through holes from the upper end side of the PC steel material 6A; 6B and fixed to the upper surface of the bearing plate 8. And the tension | tensile_strength (pre-stress) is introduce | transduced to PC steel 6A; 6B by pulling the edge part of PC steel 6A; 6B extended upwards of the foundation side fixing | fixed part 10 with the hydraulic jack as a tension | tensile_strength introduction apparatus. Then, the wedge 15 is fixed by being driven into the plurality of fixing holes of the base side fixing unit 10. Finally, the head cap 11 is fixed to the upper surface of the base 7 to protect the base-side fixing unit 10 and the rust preventive material is injected from the injection hole outside the figure, whereby the installation of the ground anchor 1 is completed.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the said embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made to the above-described embodiment, and it is obvious that such changes and modifications can be included in the technical scope of the present invention. It is clear from the description.

1 ground anchor, 2 structure foundation, 3 ground, 4 fixing hole, 6A; 6B PC steel,
9 base side elastic body, 10 base side fixing part, 16 sheath tube, 17 upper support plate,
18 Lower bearing plate, 19 Upper load bearing body, 20 Lower load bearing body,
21A; 21B fixing hole side fixing portion, 22A; 22B hole inner elastic body.

Claims (3)

A bearing plate located in a fixing hole excavated in the ground;
A foundation-side fixing unit on a structure foundation that penetrates the bearing plate, one end is fixed to the ground via a fixing hole side fixing unit below the bearing plate, and the other end is constructed on the ground. A ground anchor provided with a tension introduction material fixed to the ground via,
A hole inner elastic body inserted between the fixing hole side fixing portion and the pressure bearing plate;
A ground anchor comprising a foundation-side elastic body interposed between the foundation-side fixing portion and the structure foundation.   The ground anchor according to claim 1, wherein the tension-introducing material is plural, and the hole-side elastic body and the base-side elastic body are inserted for each of the plurality of tension-introducing materials. A plurality of the support plates are arranged along the extending direction of the fixing holes,
The ground anchor according to claim 1 or 2, further comprising a load-bearing body that is in contact with the bearing plate between the plurality of bearing plates and between the bearing plate and the structure foundation.

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