JP2001115449A - Anchor head part fixing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To introduce a large tensioning force while avoiding the increase in the total height and the diameter. SOLUTION: An anchor 12 is fixed at a deep part by grouting a grout 16 in a drilled hole 14 in a slope ground 10, and a tendon 18 for tensioning is arranged inside the anchor 12. A fixing structure part 20 forms a concrete slope work 22 on a face side of the slope ground 10, and is arranged on this slope work 22, and comprises a small-diameter coned disk spring 24 (an elastic member), a disk-like support plate 26, a fixing piece 28 and a head cap 30. The small-diameter coned disk spring 24 is interposed between the support plate 26 and a seat plate 32, and energizes these components in the separating direction from each other, and arranged concentric around the axis of the tendon 18, and surrounds the outer circumference of the tendon 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor head fixing structure, and more particularly to an anchor head fixing structure using an elastic member.

[0002]

2. Description of the Related Art As a measure for stabilizing a structure such as a ground, a slope, and a retaining wall where a landslide is likely to occur, for example, a ground anchor method in which an anchor is buried in a stabilization target such as the ground is known. .

An anchor buried by the ground anchor method has a head, a pulling portion, and a fixing portion, and a tension tendon is disposed inside. The tendon is covered with a sheath tube at the tension portion, and is fixed in the ground by grout at the anchoring portion.

When a tension is applied to the tendon, a tension device such as a jack is attached to the head, and the tension is introduced by pulling the tendon. This tension is maintained.

[0005] The tension reaction force due to the tension at this time is transmitted to the ground directly or via a support plate, and the tension reaction force is constantly applied to the ground to stabilize the ground.

In the head anchoring structure used in this type of anchoring method, a disc spring is interposed between the anchoring tool and the object to be fastened, and both are biased in a direction of separating from each other. A structure has been proposed in which the transmission of tension does not loosen during an earthquake or the like.

In this case, the disc spring is disposed on the outer periphery of the anchor rod so that the anchor rod penetrates the center thereof. However, such a fixing structure of the anchor head has the following technology. Challenges.

[0008]

That is, in the anchoring structure of the anchor head having the above-described structure, when the tension of the anchor is increased, the number of laminated disc springs is increased or the diameter is increased in response to the increase in the tension. However, if the number of stacked disc springs is increased, the total height of the disc springs will increase, and the anchor head will protrude greatly from the object to be tightened, affecting other structures. There is such a problem.

On the other hand, if the diameter of the disc spring is increased, the inner diameter of the disc spring is also increased, which makes it difficult to install the disc spring on the head of the anchor. Is high.

[0010] Further, for example, when the driving angle of the anchor is not perpendicular to the slope, there is a possibility that an eccentric load may act on the anchor head. In such a case, the center of the disc spring is attached to the anchor. If the tendons are arranged so as to penetrate, there is also a problem that the eccentric load cannot be effectively dealt with.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to avoid an increase in the total height against a large tension and to reduce the economical cost. It is another object of the present invention to provide an anchoring structure for an anchor head which can cope with the eccentric load.

[0012]

In order to achieve the above object, the present invention provides an anchor embedded in an object to be fastened such as a ground or a structure, and a projection of a tension tendon provided in the anchor. A fixing device fixed to an end; and an elastic member interposed between the fixing device and the object to be tightened and urging the fixing device in a direction to separate the fixing device and the object to be tightened. In the anchoring structure of the anchor head for transmitting the tension reaction force accompanying the tension to the object to be tightened, a plurality of elastic members are arranged around the tendon around the tendon. Made of small diameter spring material. According to the anchoring structure of the anchor head configured as described above, the elastic member interposed between the fixing tool and the object to be tightened and biasing the both in the direction of separating them is provided around the tendon and its outer periphery. Since it is composed of a plurality of small-diameter spring members arranged so as to surround the tendon, it is possible to cope with an increase in the tension applied to the tendon by increasing the number of small-diameter spring members surrounding the tendon. . Further, an elastic member interposed between the fixing tool and the object to be tightened and configured to urge the both in a direction separating from each other is constituted by a plurality of small-diameter spring members disposed around the tendon and around the outer periphery thereof. Then, when the eccentric load is applied, the plurality of small-diameter spring members can be individually deformed with respect to the applied load, and therefore can cope with the eccentric load to some extent. The plurality of small-diameter spring members can be annularly arranged around the tendon as a center. According to this configuration, it is possible to easily balance the arrangement of the small-diameter spring members, and to easily cope with an increase in the tension applied to the tendon by increasing the number of concentric circles. A support plate is installed between the fixing tool and the small-diameter spring material, and a plurality of cylindrical projections serving as positioning and mounting guides and stoppers for the small-diameter spring material are provided on the support plate, or on the tightening target side. Can be provided. According to this configuration, when a plurality of small-diameter spring members are mounted on the cylindrical projection, the positioning and arrangement thereof is completed, so that handling is simplified and workability is improved.
As the spring material, a small diameter disc spring can be suitably used. A spring receiving block may be interposed between the small-diameter spring material and the object to be tightened, and the spring receiving block may be provided with an insertion guide hole for the cylindrical projection. According to this configuration, since the deformation behavior of the small-diameter spring material is regulated by inserting the cylindrical projection into the insertion guide hole of the spring receiving block, the elastic deformation of the small-diameter spring material is stabilized.
The small-diameter spring material is housed in upper and lower unit boxes, and in the upper or lower unit box,
A guide portion serving as a positioning mounting guide and a stopper for the small-diameter spring material can be provided. According to this configuration, the small-diameter spring material is housed in the upper and lower unit boxes and unitized, so that the handleability is further improved.

[0013]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG.
3 to 3 show a first embodiment of the anchor head anchoring structure according to the present invention.

The fixing structure shown in FIG. 1 illustrates a case where the present invention is applied to a ground anchor method. FIG.
Are anchors 12 in the slope ground 10 to be tightened.
It is sectional drawing of the state which embedded and installed.

The anchor 12 is fixedly installed at a deep portion by injecting a grout material 16 into a drilled hole 14 excavated in the slope ground 10.
A tendon 18 for tension is provided in 2.

The tendon 18 has a form in which a steel wire or a steel material is covered with a sheath. Anchor 12 is slope ground 10
A fixing structure portion 20 is provided on the side of the head projecting outward from the fixing member.

The fixing structure 20 of the present embodiment is a
0, forming a concrete slope 22 on the surface side,
It is arranged on the slope 22 and includes a plurality of small-diameter disc springs 24 (elastic members), a disk-shaped supporting plate 26, a fixing device 28, and a head cap 30.

A pedestal plate 32 is fixed to the upper end surface of the slope 22 and a through hole 34 for inserting the tendon 18 is formed at the center of the pedestal plate 32. A cylindrical guide pipe 36 is inserted through the inner peripheral side of.

The guide pipe 36 is open at the upper and lower ends and extends vertically along the longitudinal direction of the inserted tendon 18. The upper end of the guide pipe 36 contacts the lower surface of the support plate 26. Have been.

The small-diameter disc spring 24 is interposed between the supporting plate 26 and the pedestal plate 32 and urges both of them in a direction away from each other. As shown in FIG. 2, the arrangement is annularly arranged around the tendon 18 so as to surround the outer periphery thereof.

In the case of this embodiment, the center of each small diameter disc spring 24 is arranged on a concentric circle with the central axis of the tendon 18 as the axis, and with the central axis of the tendon 18 as the axis. They are symmetrically arranged such that one pair faces each other.

As shown in detail in FIG. 3, each small-diameter disc spring 24 has a substantially truncated cone shape in appearance, and small- and large-diameter through holes 24a and 24b are formed at upper and lower ends. The small-diameter through hole 24a has a size that allows the inner guide pipe 36 to be inserted.

In the case of this embodiment, as shown in FIG. 3, the small-diameter disc spring 24 is formed by stacking two small-diameter disc springs one on top of the other so that the large-diameter through holes 24b contact each other. Further, in a state of being stacked in two layers, a total of four sets are arranged on the outer periphery of the tendon 18 at equal angular intervals.

Small-diameter disc spring 2 laminated in such a state
4 is inserted into a cylindrical projection 38 having one end fixed so as to protrude to the lower surface side of the support plate 26, and is arranged in a positioned state.

A plurality of cylindrical projections 38 are arranged concentrically at a predetermined interval so that the small-diameter disc spring 24 is arranged on the outer periphery of the tendon 18 in the above-mentioned state. The spring 24 serves as a guide for positioning and mounting.
2 is set so as to be separated from the upper end of the base plate 2 at a predetermined interval. For example, when a large earthquake or the like is applied, the tip of the base plate 32 comes into contact with the pedestal plate 32, so that the small-diameter disc spring 24 cannot be recovered. It also has a function as a stopper that protects against the application of force.

A joint plate 40 having a diameter smaller than that of the support plate 26 is mounted on the upper surface of the support plate 26, and a fixing device 28 is installed on the upper surface of the joint plate 40.
The fixing device 28 includes a fixing plate 28a and a wedge cone 28b.
And

The head cap 34 has a cylindrical shape with both ends opened, and is vertically fixed to the outer peripheral edge of the support plate 26 so as to cover the outer peripheral side of the small diameter disc spring 24.
When tension is applied to the tendon 18 of the anchor 12, a tension device such as a jack is attached to the end of the tendon 18 before the fixing device 28 is attached, and tension is introduced by pulling the tendon 18. .

Then, in this state, the fixing plate 28a is placed on the upper surface side of the joint plate 40, and the wedge cone 28b is mounted on the outer peripheral side of each tendon 18, and the wedge cone 28b is inserted into the tapered hole of the fixing plate 28a. Insert
Eliminate the tension of the tensioning device.

When the tensile force is removed, the tension reaction force introduced into the tendon 18 is applied to the support plate 2 via the fixing device 28.
The supporting plate 26, which is transmitted to the tension plate 6 and receives the tension reaction force, transmits the tension reaction force via the small-diameter disc spring 24 to the base plate 3.
2

The pedestal plate 32 is formed substantially on the slope ground 1.
0, and the slope ground 10 is stabilized by receiving the tension reaction force. In the state where the installation of the ground anchor is completed, the small-diameter disc spring 24 is compressed and deformed by receiving the tension reaction force from the support plate 26, so that the support plate 26 and the pedestal plate 32 are separated from each other. Biased in the direction.

According to the anchoring structure of the anchor head configured as described above, the anchoring device is interposed between the anchoring tool 28 and the ground 10 (an object to be tightened), and urges them in a direction separating from each other. Since the elastic member is composed of a plurality of small-diameter disc springs 24 (spring material) arranged around the tendon 18 around its periphery, when the tension introduced into the tendon 18 increases, the tendon 18 Can be dealt with by increasing the number of small-diameter disc springs 24 (spring material) surrounding.

For this reason, a large tension can be introduced without increasing the total height of the spring material, and the amount of protrusion of the anchor head projecting outward from the ground 10 can be suppressed. Can be prevented from affecting other structures.

If the number of small-diameter disc springs 24 (spring material) is increased to cope with the increase in the tension, the diameter of the disc springs can be prevented from increasing, so that it is specially manufactured. It doesn't require any technology and is economical.

Further, an elastic member which is interposed between the fixing tool 28 and the ground 10 (the object to be tightened) and urges the two in a direction to separate them is arranged so as to surround the outer periphery of the tendon 18 as a center. A plurality of arranged small diameter disc springs 24 (spring material)
When the eccentric load is applied, the plurality of small-diameter disc springs 24 (spring material) can be individually deformed with respect to the applied load. It has a degree of freedom and can cope with eccentric loads to some extent.

In this embodiment, the small diameter disc spring 2
4 (spring material) is arranged annularly so as to face a concentric circle centered on the tendon 18, so that the small-diameter disc spring 24
It is possible to easily balance the arrangement of the (spring material) and easily cope with an increase in the tension introduced into the tendon 18 by increasing the number of concentric circles.

Further, in the case of the present embodiment, since the supporting plate 26 is provided with a plurality of cylindrical projections 38 serving as a mounting guide and a stopper for the small-diameter disc spring 24 (spring material), the cylindrical projections are provided. When a plurality of spring members are mounted on the portion 38, the positioning and arrangement thereof is completed, so that handling is simplified and workability is improved.

It should be noted that the cylindrical projecting portion 38 is
The same function can be obtained by providing the pedestal plate 32 instead of 6.

FIG. 4 shows a second embodiment of the anchor head anchoring structure according to the present invention. The same or corresponding parts as those in the above embodiment are denoted by the same reference numerals and description thereof is omitted. In addition, only the characteristic points will be described below.

In the embodiment shown in FIG.
The laminated small-diameter disc spring 24 is used as an elastic member that urges in the direction separating the base 6 and the pedestal plate 32.

Then, the small diameter disc spring 24 and the pedestal plate
A disc-shaped spring receiving block 50 is interposed between the (tightening target) 32. This spring receiving block 50
A plurality of insertion guide holes 52 fixed to the pedestal plate 32 side and movably guiding the plurality of cylindrical protrusions 38 protruding from the lower surface of the support plate 26 are formed in the axial direction. Have been.

The outer diameter of the spring receiving block 50 is slightly smaller than the inner diameter of the annularly formed head cap 30, and the head cap 30 is guided along the outer peripheral edge of the spring receiving block 50. , Can be moved up and down.

According to the fixing structure configured as described above, the small diameter disc spring 24 is inserted into the cylindrical projection 38 on the inner peripheral side, and the upper side contacts the lower surface of the support plate 26, and the lower side of the spring receiving block 50. The cylindrical projection 38 is in contact with the upper surface.
Is inserted into the insertion guide hole 52 of the spring receiving block 50, its behavior is regulated, so that the elastic deformation of the small diameter disc spring 24 is stabilized.

When such a spring receiving block 50 is used, the small-diameter disc spring 24 is isolated from the outside in a deformable state, so that invasion and adhesion of dust and the like can be prevented and stable for a long time. It can withstand use in the condition.

FIG. 5 shows a third embodiment of the anchor head anchoring structure according to the present invention. The same or corresponding parts as those in the above embodiment are denoted by the same reference numerals and description thereof is omitted. In addition, only the characteristic points will be described below.

In the embodiment shown in FIG.
The laminated small-diameter disc spring 24 is used as an elastic member that urges in the direction separating the base 6 and the pedestal plate 32.

In this embodiment, the small-diameter disc springs 24 are stacked, and the upper and lower unit boxes 54 and 5 are stacked.
6. The upper and lower unit boxes 54 and 56 are each formed in a circular concave shape with one end opened, the open ends are fitted with each other, and the hollow cylindrical upper and lower guide portions 5 with both ends opened at the center.
8,60 are provided.

The upper and lower guide portions 58, 60
Is a positioning guide for accommodating the small-diameter disc spring 24 therein, and the upper and lower unit boxes 54 and 56 are vertically movably fitted.

The cylindrical projection 38 is fitted and inserted into the upper and lower guides 58 and 60 fitted to each other. When the cylindrical projection 38 is not provided on the support plate 26, a recess is provided on the lower surface of the support plate 26, in which the upper unit box 54 can be fitted, instead of the projection 38.
A lower unit box 56 is provided on the upper surface side of the base plate 32.
May be provided.

According to the fixing structure configured as described above,
The small-diameter disc spring 24 is connected to the upper and lower unit boxes 5.
Since it is housed in the unit 4,56 and unitized, the handleability is further improved.

FIGS. 6 to 8 show a modification of the third embodiment shown in FIG. 5. In the example shown in FIG. 5, the upper and lower units for accommodating the small diameter disc springs 24 in a stacked state are shown. It has boxes 54a and 56a.

The upper and lower unit boxes 54a,
56a is formed in a circular concave shape with one end opened,
A hollow cylindrical upper guide portion 58a is provided at the center of the upper unit box 54a. The lower unit box 56a has a through hole 62 at the center thereof through which the upper guide portion 58a can be inserted.

The lower unit box 56a has a part on the upper end side inserted into the upper unit box 54a. Even when the upper and lower unit boxes 54a and 56b configured as described above are used, the same operation and effect as those of the third embodiment can be obtained.

The example shown in FIG. 7 has upper and lower unit boxes 54b and 56b for storing the small diameter disc springs 24 in a stacked state.

The upper unit box 54b is formed in a circular concave shape with one end opened, and a hollow cylindrical upper guide portion 58b is provided at the center of the upper unit box 54b. The lower unit box 56b is formed in a disk shape, and has a through hole 64 at the center thereof through which the upper guide portion 58a can be inserted.

The lower unit box 56b is inserted inside the upper unit box 54b so as to close the opening. Even when the upper and lower unit boxes 54b and 56b configured as described above are used, the same operation and effect as those of the third embodiment can be obtained.

In the example shown in FIG. 8, the small diameter disc spring 24 is
In a stacked state, the upper and lower unit boxes 5
4c, 56c. The upper and lower unit boxes 54c and 56c are formed in a circular concave shape with one end opened, and provided with hollow cylindrical upper and lower guide portions 58c and 60c at the center.

The upper and lower guide portions 58c, 60
c, which are fitted to each other, connect the upper and lower unit boxes 54c, 56c to be vertically movable. A spline structure 64 is provided between the fitting surfaces of the upper and lower guides 58c and 60c.

Even when the upper and lower unit boxes 54c and 56c configured as described above are used, the same operation and effect as in the third embodiment can be obtained.

In the above embodiment, the small diameter disc spring 24 is exemplified as the elastic member. However, the present invention is not limited to this. For example, a small diameter coil spring, a leaf spring,
A member having a similar function such as rubber may be used. Even when the small-diameter disc spring 24 is used, it is not always necessary to stack them, and various forms may be selected according to the tension introduced into the tendon 18.

Further, the fixing structure of the present invention has a
Not only can it be applied when tightening 0,
The present invention can also be applied to a case where a prestress force is introduced into a structure.

[0061]

As described above in detail in the embodiments,
ADVANTAGE OF THE INVENTION According to the anchoring structure of the anchor head concerning this invention, it can respond economically to large tension, avoiding the increase in total height, and also responds to an eccentric load. be able to.

[0062]

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view of an installation state of a ground anchor employing a fixing structure of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a detailed view of the disc spring shown in FIG. 1;

FIG. 4 is an explanatory sectional view of a main part showing a second embodiment of the fixing structure of the present invention.

FIG. 5 is an explanatory sectional view of a main part showing a third embodiment of the fixing structure of the present invention.

FIG. 6 is an explanatory sectional view of a main part showing a fourth embodiment of the fixing structure of the present invention.

FIG. 7 is an explanatory sectional view showing a main part of a fifth embodiment of the fixing structure of the present invention.

FIG. 8 is an explanatory sectional view of a main part showing a sixth embodiment of the fixing structure of the present invention.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 10 Slope ground 12 Anchor 18 Tendon 20 Anchoring structure part 24 Small diameter disc spring 26 Support plate 28 Anchor

Claims (6)

[Claims] An anchor embedded in an object to be fastened such as a ground or a structure, a fixing device fixed to a projecting end of a tension tendon provided in the anchor, the fixing device and the object to be tightened. And an elastic member interposed between the tendons and the biasing member in a direction to separate them from each other. A tension is introduced into the tendon via the fixing device, and a tension reaction force caused by the tension is applied to the tightening target. In the anchoring structure for an anchor head transmitting to an object, the anchoring member is characterized in that the elastic member is constituted by a plurality of small-diameter spring members arranged around the tendon and around the outer periphery thereof. Construction. 2. The anchor head anchoring structure according to claim 1, wherein the plurality of small-diameter spring members are annularly arranged around the tendon as a center. 3. A supporting plate is provided between the fixing device and the small-diameter spring material, and a plurality of cylindrical projections serving as positioning and mounting guides and stoppers for the small-diameter spring material are provided on the supporting plate or the supporting member. 3. The anchor head anchoring structure according to claim 2, wherein the anchor head anchoring structure is provided on a tightening target side. 4. The anchor head fixing structure according to claim 1, wherein the spring member is made of a small diameter disc spring. 5. A spring receiving block is interposed between the small-diameter spring member and the object to be tightened, and an insertion guide hole for the cylindrical projection is provided in the spring receiving block. 5. The anchoring structure for an anchor head according to 3 or 4. 6. The small-diameter spring material is housed in upper and lower unit boxes, and the upper or lower unit box is provided with a guide portion serving as a positioning mounting guide and a stopper for the small-diameter spring material. The anchor head anchoring structure according to claim 3 or 4, wherein the anchor head anchoring structure.