JP7041425B2 - Load transmission part structure from anchor to pressure receiving plate - Google Patents

Description

The present invention relates to a load transfer structure from an anchor to a pressure receiving plate, and in particular, in a slope stabilizing system including an anchor and a pressure receiving plate having a pedestal on which an anchor head (anchor head) is placed. It relates to the structure of the load transmission part from the anchor to the pressure receiving plate.

Conventionally, in order to stabilize slopes (natural slopes and cut soil), anchors are provided so as to penetrate from the surface of the slope to the stable ground, and as a reaction force structure of the anchor head, the slope is located at the end of the anchor surface on the ground surface side. A pressure plate made of concrete blocks with a substantially cross shape or a rectangular shape that can cover a wide area is attached, and the tension force of the anchor is transmitted to the slope via the pressure plate. It had been.

When the tension force by the anchor is applied to the pressure receiving plate, the load is concentrated on the joint portion of the pressure receiving plate with the anchor, and therefore the stress is concentrated on the joint portion, which causes the pressure receiving plate to be damaged. In particular, in a pressure receiving plate that employs a member with higher strength than other parts at the joint, the load is transmitted from the joint to other parts in order to prevent damage to the pressure receiving plate at the boundary between the two. It is important to optimize.

Patent Document 1 discloses an invention for optimizing a stress state caused by a tension force from an anchor at a joint portion of a pressure receiving plate with an anchor.

Specifically, in Patent Document 1, as shown in FIGS. 8A and 8B, a substantially cross-shaped concrete pressure receiving plate 80 having four arms and an upper end portion of an anchor 81 are joined to each other. Discloses a steel pedestal 85 having a bottom portion 86 having a hole 86a through which an anchor 81 is inserted and a downwardly tapered conical cylinder portion 87 on an upper surface 80b of a pressure receiving plate central portion 80a. An anchor plate (not shown) having a diameter larger than that of the anchor head 88 may be provided between the pedestal 85 and the anchor head 88 constituting the joint portion.

The bottom 86 of the pedestal 85 forms a bearing board that supports the upper end of the anchor 81.

According to the pedestal 85 of Patent Document 1, as shown in FIGS. 8A and 8B, the tension or load from the anchor 81 is transmitted to the pedestal 85 via the bearing plate (bottom 86). The conical cylinder portion 87 of the pedestal 85 is dispersed in a diagonal direction (arrow-viewing direction) with respect to the axis A of the pressure receiving plate 80, that is, in the arm portion direction of the pressure receiving plate 70. As a result, the load is distributed from the anchor 81 to the pedestal 85, and further from the pedestal 85 toward the sufficiently long arm portion of the pressure receiving plate 80, and it is necessary even if the thickness of the pressure receiving plate in the axis A direction is reduced. A pressure receiving plate that can handle a load can be configured. In the configuration having such a pedestal 85, when a load is transmitted from the high-strength anchor receiving member to the main body portion (pressure receiving plate 80) of the pressure receiving plate whose strength is relatively low, the anchor 81 and the pressure receiving plate are Stress concentration at the joint is avoided, which is advantageous.

In addition, when installing the pressure receiving plate on the slope of the ground, it is rare that the anchor is perpendicular to the bottom surface of the pressure receiving plate, and the range of the intersection angle between the two is generally in the range of 90 ° to 105 °. Is.

If the pedestal 85 of Patent Document 1 is used as it is when the crossing angle between the two deviates from the vertical, the anchor 81 bends at the lower end of the anchor head 88 as shown in FIG. 9, and the protective layer is damaged or the anchor is broken. There is a risk that the strength will decrease.

Therefore, conventionally, when the crossing angle between the two deviates from the vertical, as shown in FIG. 10, when manufacturing the pressure receiving plate at the factory, an angle corresponding to the assumed crossing angle between the anchor and the bottom surface of the pressure receiving plate is set. It has been proposed to fit the pedestal 90 onto the upper surface of the pressure receiving plate.

However, when the angle is set, the bottom portion 86 of the pedestal 90 further sinks downward, the thickness of the pressure receiving plate at the lower part of the pedestal is reduced, and the proof stress of the pressure receiving plate is structurally lowered. Further, by angling the pedestal 90, the distribution direction of the load from the conical tube portion 87 toward the pressure receiving plate changes, and the main body of the relatively low-strength pressure receiving plate in the fitting portion of the pedestal 90 is damaged. It is also a concern. Furthermore, the angle adjustment of the pedestal at the time of manufacturing the pressure receiving plate in the factory means that the angle adjustment is required for each manufacturing, so it is limited to build-to-order manufacturing, and the cost of manufacturing the pressure receiving plate by mass production of standard products Make the decline difficult.

In addition, even if the assumed angle of intersection between the anchor and the bottom surface of the pressure receiving plate and the fitting angle of the receiving pedestal to the pressure receiving plate are matched, the angle between the two may deviate by several degrees depending on the condition of the slope on the actual slope. It's common. Since the action of the force changes even with a slight deviation, the load distribution effect as designed may not be obtained.

Patent Document 2 discloses a pressure receiving plate provided with a ball seat that can cope with such an angular deviation. Specifically, it has a hole for inserting an anchor, a substantially central portion of a pressure receiving plate having a substantially cross shape in a plan view in which a substantially hemispherical concave spherical seat is formed at the upper portion, and a convex spherical surface corresponding to the concave spherical seat. Disclosed is an anchor head formed as a convex rotating body having a bottom surface thereof, and a pressure receiving plate made of a steel material having the anchor head.

According to this, at the installation site of the pressure receiving plate, the convex spherical surface of the anchor head is a concave spherical surface even when the angle of the anchor is not perpendicular to the bottom surface of the pressure receiving plate and the angle deviates from the vertical. By sliding on it, the angle is adjusted and the anchor is prevented from bending.

Japanese Unexamined Patent Publication No. 11-21886 Japanese Unexamined Patent Publication No. 11-158870

According to the pressure receiving plate of Patent Document 2, the convex spherical surface of the anchor head slides on the concave ball seat to adjust the angle and prevent the anchor from bending, but the concave ball seat is adopted. The large load transmitted from the anchor tends to be concentrated on the lower side of the pressure receiving plate via the concave spherical seat. That is, when the convex spherical surface and the concave spherical seat of Patent Document 2 are adopted for the pressure receiving plate whose main body strength is smaller than the strength of the anchor receiving member, the pressure receiving plate may be damaged in the lower region of the anchor receiving member. I am concerned.

The present invention has been made in view of the above problems, and an object thereof is to accurately disperse the load transmitted from the anchor to the entire pressure receiving plate and to reduce the labor of the pressure receiving plate manufacturing work. It is an object of the present invention to provide a structure for transmitting a load from an anchor to a pressure receiving plate, which can achieve both optimization of the angle between the bottom surface and the anchor.

The invention according to claim 1 for achieving the above object has an anchor having a head at an upper end portion and is embedded in a slope of a ground with at least the head exposed, and the anchor is inserted through the anchor. It has a pedestal on which the head of the inserted anchor is placed, and a recess formed so that the pedestal can be fitted, and has a tension force on the ground of the anchor. In a load transfer section structure from an anchor to a pressure receiving plate in a slope stabilization system comprising a main body portion that receives the bearing through the pedestal, and a pressure receiving plate that is pressed and installed on the slope.
The pedestal has a bottomed conical pedestal shape that tapers toward the ground in the pressed installation state of the pressure receiving plate, and has an inclined side wall formed by hollowing out the inside and a bottom continuous with the side wall. An insertion hole having a wall portion through which the anchor is inserted is provided in the bottom wall portion, and at least the compression strength is set to be larger than that of the main body portion of the pressure receiving plate, and the inner surface of the bottom wall portion is the above. The bottom outer surface, which is formed as a concave spherical surface extending to at least a part of the inner surface of the side wall portion and is mounted on the pedestal at the anchor head, is substantially the same as the concave spherical surface of the pedestal. It is formed as a convex spherical surface having the same curvature, and the extending region of the concave spherical surface is larger than the region of the convex spherical surface .

According to this configuration, the pedestal is fitted into the recess of the pressure receiving plate main body, and the anchor head is placed on the pedestal in a state where the upper end of the anchor (the upper end of the uncurtain don) is connected to the anchor head. Is a state in which the outer surface of the anchor head, which is a convex spherical surface, is slidable on a predetermined region, which is a concave spherical surface of the inner surface of the bottom wall portion of the pedestal. As a result, at the installation site of the pressure receiving plate on the ground, the angle of the anchor with respect to the bottom surface of the pressure receiving plate when the anchor is attached to the pressure receiving plate can be changed within a predetermined range, for example, from the vertical to the angle range before and after the anchor. ..

Further, since the large load transmitted from the anchor to the receiving pedestal can be distributed to the pressure receiving plate main body through the outer surface of the conical side wall portion of the receiving pedestal, the joint portion of the receiving pedestal with the anchor. It is possible to avoid the stress concentration in the joint portion and reduce the risk of damage to the pressure receiving plate main body portion having at least a compressive strength smaller than that of the pedestal pedestal.

According to the second aspect of the present invention, in the load transmitting portion structure from the anchor to the pressure receiving plate according to the first aspect, the insertion hole of the pedestal and the through hole through which the anchor penetrates in the main body of the pressure receiving plate are formed. A substantially cylindrical hole extending in a position and direction corresponding to an assumed crossing angle between the anchor and the bottom surface of the main body of the pressure receiving plate when the pressure receiving plate is pressed and installed on the slope of the ground. It is characterized by being provided as.

According to this configuration, the pedestal and its lower region can be formed more densely as compared with the case where the tapered insertion hole and the through hole are formed, so that the load on the lower region of the pedestal where stress is easily concentrated can be accurately applied. Can be dispersed in.

According to a third aspect of the present invention, in the load transmitting portion structure from the anchor to the pressure receiving plate according to the first or second aspect, the outer surface of the side wall portion of the pedestal and the outer surface of the bottom wall portion of the pedestal. The angle formed by the anchor is 55 ° or more and 65 ° or less.

According to this configuration, the large load transmitted from the anchor to the pedestal can be most effectively distributed to the pressure receiving plate main body portion via the outer surface of the side wall portion having a conical shape.

The invention according to claim 4 is the upper portion of the load transmitting portion structure from the anchor to the pressure receiving plate according to any one of claims 1 to 3, wherein the anchor head has a means for connecting to the upper end portion of the anchor. It is characterized in that it is a combination of a connecting member and a bottom member having the outer surface that becomes the convex spherical surface.

According to this configuration, where the size of the anchor used and the corresponding anchor head differ depending on the anchor force required to stabilize the slope of the ground, only the top coupling member is changed and the bottom member is always It is possible to use the same one.

As a result, regardless of the required anchor force, only the upper coupling member is changed, and the load distribution and angle optimization functions are performed without changing the pedestal and the bottom member of the anchor head required for angle adjustment. It can be demonstrated.
The invention according to claim 5 is characterized in that, in the load transmitting portion structure from the anchor to the pressure receiving plate according to any one of claims 1 to 4, the upper end portion of the anchor is made of a PC steel wire. ..

According to the load transmission portion structure from the anchor to the pressure receiving plate of the present invention, the pedestal is fitted into the recess of the pressure receiving plate main body portion, and the upper end portion of the anchor (the upper end portion of the uncurtain don) is connected to the anchor head. The mounting state of the anchor head on the pedestal is a state in which the outer surface of the anchor head, which is a convex spherical surface, is slidable on a predetermined region, which is a concave spherical surface of the inner surface of the bottom wall of the pedestal. be. As a result, at the installation site of the pressure receiving plate on the ground, the angle of the anchor with respect to the bottom surface of the pressure receiving plate when the anchor is attached to the pressure receiving plate can be changed within a predetermined range, for example, from the vertical to the angle range before and after the anchor. ..

Therefore, it is possible to optimize the crossing angle between the bottom surface of the pressure receiving plate and the anchor without increasing the labor of manufacturing the pressure receiving plate, and it is possible to maintain the anchor in a substantially straight line state at the joint with the upper end of the anchor. Become.

Further, since the large load transmitted from the anchor to the receiving pedestal can be distributed to the pressure receiving plate main body through the outer surface of the conical side wall portion of the receiving pedestal, the joint portion of the receiving pedestal with the anchor. It is possible to avoid the stress concentration in the joint portion, reduce the possibility that the pressure receiving plate main body portion having a strength smaller than that of the pedestal pedestal is damaged, and more effectively stabilize the slope.

(A) is a plan view of a pressure receiving plate including a load transmitting portion structure 10 from an anchor to a pressure receiving plate according to an embodiment of the present invention, and ( _B ) is a sectional view taken along line IB- _IB of the same figure. It is sectional drawing of the slope S of the ground protected by the slope stabilization system 1 which has the load transmission part structure 10 from an anchor to a pressure receiving plate. FIG. 2 is an enlarged view of part a in FIG. It is the same enlarged view as FIG. 3 which shows the 1st modification of the main body part 4 of the pressure receiving plate 3 and the receiving pedestal 20. It is the same enlarged view as FIG. 3 which shows the 2nd modification of the main body part 4 of the pressure receiving plate 3 and the receiving pedestal 20. It is the same cross-sectional view as FIG. 1 (B) which shows the modification of the anchor head 12. It is the same cross-sectional view as FIG. 1 (B) which shows the further modification example of an anchor head 12. It is (A) plan view and (B) VIII _B -VIII _B line cross-sectional view which shows the structure of the joint part with the anchor of the pressure receiving plate in the same figure. It is a figure which shows the bending state of the anchor in the conventional joint structure with the anchor of a pressure receiving plate. It is a figure which shows the structure of the joint part with the anchor of the pressure receiving plate which tilted the receiving pedestal with respect to the main body part of the pressure receiving plate in the conventional.

Next, an embodiment of the present invention will be described in detail with reference to the drawings. 1 (A) is a plan view of a pressure receiving plate including a load transmitting portion structure 10 from an anchor to a pressure receiving plate, FIG. 1 ( _B ) is a sectional view taken along line IB- _IB of FIG. 1 (A), and FIG. 2 is an anchor. A cross-sectional view of the slope S of the ground protected by the slope stabilization system 1 having the load transmission portion structure 10 from the to the pressure receiving plate, and FIG. 3 is an enlarged view of the portion a of FIG.

In the present invention, an anchor 2 having a head (anchor head 12) on an upper end 2a (upper end of an uncurtain don), a pedestal 20 on which the anchor head 12 is placed, and a main body into which the pedestal 20 is fitted. It is a load transmission structure 10 from an anchor to a pressure receiving plate in a slope protection system 1 including a pressure receiving plate 3 having a portion 4.

As shown in FIG. 2, the anchor 2 is embedded in the slope S of the ground with the head (anchor head 12) exposed. Examples of the slope S include a slope formed by excavating a ground. As shown in FIG. 2, the slope S is formed of, for example, a weathered unstable layer G2 (surface portion) of 1 m to 3 m and a stable layer G1 (stable ground) existing beneath the weathered unstable layer G2 (surface portion).

After the anchor 2 is inserted into the anchor hole 7 formed in the slope S, cement milk 8 is injected into the anchor hole 7, and the anchor 2 is fixed and installed on the slope S. The diameter φ of the anchor hole 7 is in the range of 60 mm to 200 mm, preferably 80 mm to 140 mm. In this state, the lower end portion 2b of the anchor 2 is fixed to the stable stratum G1, and the upper end portion 2a of the anchor 2 is maintained in a state of being exposed to the ground surface.

The anchor 2 corresponds to, for example, a lock bolt or a ground anchor used in the ground anchor construction method. The anchor 2 can be appropriately selected according to the assumed anchor force. For example, when the assumed anchor force exceeds 10 tons, the ground anchor is used as the anchor 2, and when the assumed anchor force is 10 tons or less, the lock bolt is used as the anchor 2. In this embodiment, a ground anchor is used as the anchor 2. A pressure receiving plate 3 is attached to the anchor 2.

The pressure receiving plate 3 mainly includes a main body portion 4 and a receiving pedestal 20 fitted in a recess 4a provided in a substantially central portion of the main body portion 4.

The main body 4 may have any shape as long as it is a plate member to which tension is applied by the anchor 2 and can widely cover the slope. For example, the main body 4 may have various shapes such as a circular shape and a polygonal shape in a plan view. In this embodiment, a substantially cross-shaped one having four arms 4c, 4c, 4c, and 4c is used.

Further, the bottom portion 4aa of the recess 4a is provided with a substantially cylindrical through hole 4b through which the anchor 2 penetrates. In the present embodiment, the through hole 4b is bored perpendicular to the bottom surface 4d of the main body portion 4, and the angle β between the anchor 2 and the bottom surface 4d of the main body portion 4 (see FIG. 1B). ) Is in the range of vertical ± 2.5 °, the anchor 2 has an inner diameter such that the peripheral surface of the through hole 4b does not come into contact with each other.

The main body 4 is formed by using a material having a compressive strength at least lower than that of the anchor head 12 and the pedestal 20, which will be described later, as a base material (that is, the pedestal 20 has at least a higher compressive strength than the main body 4). It is set). Examples of such a base material include concrete and resin.

Examples of concrete include precast concrete, prestressed concrete, high-strength concrete, reinforced concrete and the like.

Further, as the resin, a thermosetting resin is used, and it is preferable that the thermosetting resin foam is used from the viewpoint of weight reduction. As the thermosetting resin foam, urethane resin foam, epoxy resin foam, unsaturated polyester resin foam, and melamine resin foam can be used. In particular, it is preferable to use urethane resin foam.

Fiber may be added to the base material to impart strength. As the fiber, synthetic fiber such as glass fiber, carbon fiber, metal fiber, chemical fiber and the like can be used, but from the viewpoint of strength and cost, it is preferable to use glass fiber. That is, when the base material is a resin, it is preferable to use FRP to which fibers are added.

The compressive strength can be measured according to, for example, JIS A 1108. Further, the pedestal 20 may be set to have a higher bending strength and tensile strength than the main body portion 4. The bending strength can be measured according to, for example, JIS A 1106, and the tensile strength can be measured according to, for example, JIS A 1113.

In the present embodiment, as shown in FIG. 1 (B), the pedestal 20 has a bottomed cylindrical shape in which the inside of the cone is hollowed out, and the outer surface 21a and the inner surface 21b are in the ground direction. It has a side wall portion 21 having a tapered conical shape and a bottom wall portion 22 having a flat outer surface 22a.

The inner side surface 22b of the bottom wall portion 22 has a predetermined region that becomes a concave spherical surface. In this predetermined region, when the convex spherical surface of the bottom outer surface 14b (see FIG. 2) of the anchor head 12 described later is placed on the inner surface 22b of the bottom wall portion 22, the convex spherical surface is concave. It is defined by whether it is slidable on a spherical surface. Specifically, the predetermined region having a concave spherical surface within a range where the angle β (see FIG. 1 (B)) between the anchor 2 and the bottom surface 4d of the main body 4 can be 90 ° (vertical) ± 15 °. Is stipulated.

Further, the bottom wall portion 22 has an insertion hole 22c through which the anchor 2 is inserted. In the present embodiment, the insertion hole 22c is bored perpendicular to the bottom surface 4d of the main body portion 4, and the angle β (see FIG. 4) between the anchor 2 and the bottom surface 4d of the main body portion 4 is 90. Within the range of ° (vertical) ± 2.5 °, the anchor 2 has an inner diameter that does not come into contact with the peripheral surface of the insertion hole 22c.

The angle α formed by the outer surface 21a of the side wall portion 21 of the pedestal 20 and the outer surface 22a of the bottom wall portion 22 (see FIG. 1B) is preferably 55 ° or more and 65 ° or less. If the angle α is less than 55 °, the load may be concentrated on the side wall portion 21 and the side wall portion 21 itself may be damaged, and the load distribution of the pressure receiving plate 3 in the arm portion 4c direction becomes insufficient to receive the pressure. The main body 4 of the plate 3 may be damaged near the tip of the arm 4c. On the contrary, when the angle α is more than 65 °, the load distribution of the pressure receiving plate 3 in the arm portion 4c direction via the side wall portion 21 becomes insufficient, and the load from the anchor 2 is sent to the lower side of the bottom wall portion 22. There is a risk that the main body 4 of the pressure receiving plate 3 will be damaged below the bottom wall 22 due to concentration.

The angle α formed by the outer surface 21a and the outer surface 22a can be defined as an angle at which the linear portions of the outer surface 21a and the outer surface 22a intersect, and is a continuous portion of the actual outer surface 21a and the outer surface 22a. The corners may be chamfered or the corners may be rounded. By rounding the corners of the outer side surface 21a and the outer side surface 22a, the concentration of stress on the main body 4 portion of the pressure receiving plate 3 that abuts on the corners is alleviated.

The pedestal 20 has at least a higher compressive strength than the main body 4 of the pressure receiving plate 3. For example, while the base material of the main body 4 of the pressure receiving plate 3 is concrete or resin, the pedestal 20 is made of metal having a strength higher than that of concrete or resin. Examples of such metals include steel, cast iron, aluminum alloys and the like.

As shown in FIG. 1B, the anchor head 12 includes an upper connecting member 13 (corresponding to a so-called anchor head) having a connecting means (wedge 15) for connecting to the upper end portion 2a of the anchor, and a pedestal 20. It is composed of a combination of a bottom member 14 (corresponding to a so-called anchor plate) that comes into contact with the bottom member 14. When the bottom member 14 is used as an anchor plate as in the present embodiment, the bottom member 14 has a larger diameter than the upper connecting member 13 in a plan view from the viewpoint of receiving the load transmitted from the anchor to the upper connecting member 13. Become.

The upper connecting member 13 has a cylindrical shape having a flat top surface, a bottom surface, and a side peripheral surface, and is an anchor hole through which the upper end portion 2a (PC steel wire) of the anchor 2 penetrates the cylindrical shape in the axial direction. Has 13a. The anchor hole 13a has a shape in which the diameter of the vicinity of the top surface of the upper connecting member 13 is gradually increased.

The bottom member 14 has a substantially convex lens shape or a substantially semi-cylindrical shape that is convex downward in a side view, and has a top surface that is in surface contact with the bottom surface of the upper coupling member 13 and an inner surface surface of the bottom wall portion 22 of the pedestal 20. It has a bottom outer surface 14b having a convex spherical surface having substantially the same curvature with respect to the concave spherical surface of 22b.

Anchor holes 14c through which all four anchors 2 can penetrate are provided on the top surface of the bottom member 14, and the anchor holes 14c penetrate to the bottom outer surface 14b.

The upper connecting member 13 and the bottom member 14 are placed on the inner side surface 22b of the bottom wall portion 22 of the pedestal 20 in a state where the anchor 2 is inserted into the anchor hole 13a and the anchor hole 14c, and the tension jack (shown). After a predetermined tension is applied to the anchor 2 by (s), a wedge 15 (coupling means, see FIG. 1 (B)) is inserted into the anchor hole 13a from the top surface side of the upper coupling member 13 to form the anchor 2. The upper end portion 2a is connected to the anchor head portion 12.

Further, by inserting the anchor 2 into the anchor holes 13a and 14c in this way, the upper connecting member 13 and the bottom member 14 are connected to each other, the anchor head 12 is formed by the combination thereof, and the anchor head 12 is formed through the anchor 2. Therefore, a predetermined tension force required for stabilizing the slope S is applied to the pressure receiving plate 3.

Although the upper end portion 2a and the anchor head 12 of the anchor 2 exposed on the slope S are not shown in FIG. 2, they are covered with a known head cap after the pressure receiving plate 3 is pressed and installed on the slope S. May be good. In this case, it is preferable that the internal space of the head cap is filled with a rust preventive material.

As shown in FIG. 3 , a waterproof plug 26 for preventing water from entering the through hole 4b from the slope S side is fitted on the bottom surface 4d side of the main body 4 in the through hole 4b. Is preferable. As a result, water can be prevented from entering the through hole 4b, and corrosion of the anchor head 12 and the pedestal 20 can be suppressed. The waterproof plug 26 is provided with, for example, an anchor head 12 after the pressure receiving plate 3 is placed on the slope S with the anchor 2 embedded in the slope S of the ground penetrating the through hole 4b of the main body 4. Before being coupled to the anchor 2, the insertion hole 22c and the through hole 4b are passed through in order and fitted to the bottom surface 4d side of the main body 4 in the through hole 4b.

The waterproof plug 26 is provided with an anchor hole (not shown) corresponding to a position through which the anchor 2 passes, whereby water from the slope S side into the through hole 4b while the anchor 2 is inserted is provided. Intrusion can be prevented.

Further, the waterproof plug 26 is an elastic body such as rubber, and even if the angle β deviates within the range of about 90 ° ± 2.5 °, the anchor 2 and the anchor hole due to the deviation deviate from each other. It is preferable from the viewpoint of maintaining waterproofness while absorbing misalignment.

Alternatively, at the installation site of the pressure receiving plate 3, if the angle β deviates within a range of about 90 ° ± 2.5 ° from the assumption, it is also possible to use a waterproof plug in which the position of the anchor hole is adjusted. ..

Therefore, according to the load transmitting portion structure 10 from the anchor to the pressure receiving plate according to the present embodiment, the bottom outer surface 14b which is a convex spherical surface of the anchor head 12 is the outer surface of the bottom wall portion 22 of the pedestal 20. It becomes slidable on a predetermined region which is a concave spherical surface of 22a.

As a result, at the installation site of the pressure receiving plate 3 on the slope S of the ground, as shown in FIG. 3 , the angle β between the anchor 2 and the bottom surface 4d of the main body 4 of the pressure receiving plate 3 is ± from vertical (90 °). Even if the angle is deviated by about 2.5 °, the anchor head 12 is slid on the pedestal 20 according to the angle, and the angle between the bottom surface 4d of the main body 4 and the anchor 2 is optimized for the anchor 2. It is possible to maintain a straight state without bending.

At the same time, a large load transmitted from the anchor 2 to the pedestal 20 is sent to the main body 4 of the pressure receiving plate 3 via the outer surface 21a of the side wall portion 21 having a conical shape of the pedestal 20, especially in the direction of the arm 4c. Therefore, stress concentration at the joint portion of the pressure receiving plate 3 with the anchor 2 is avoided, and the possibility that the main body portion 4 having a strength smaller than that of the pedestal 20 is damaged at the joint portion is reduced. There is.

Further, since the anchor head 12 is a combination of the upper connecting member 13 and the bottom member 14, only the upper connecting member 13 is changed according to the anchor force required for stabilizing the slope S of the ground, and the angle is changed. The functions of load distribution and angle optimization can be exhibited without changing the pedestal 20 and the bottom member 14 required for adjustment.

In the above embodiment, it is possible to deal with the case where the angle β (see FIG. 2) between the anchor 2 and the bottom surface 4d of the main body 4 is in the range of 90 ° ± 2.5 °, but the angle β is as described above. It may deviate to the range of 90 ° ± 15 °. Therefore, two modified examples of the main body 4 and the pedestal 20 of the pressure receiving plate 3 that can cope with such a case will be described with reference to FIGS. 4 and 5 .

FIG. 5 is an enlarged view similar to FIG. 4, showing a first modification example of the main body portion 4 of the pressure receiving plate 3 and the receiving pedestal 20. In this modification, the same elements as those in the above embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in the figure, in this modification, the configurations of the through hole 4b'of the main body 4 and the insertion hole 22c' of the pedestal 20 are different from those of the above embodiment.

Specifically, in this modification, the through hole 4b'has an angle γ formed by the bottom surface 4b of the main body 4 and the axis L of the through hole 4b' at 95 °, and the angle β is 95 ° ± 2. Within the range of 5 °, the inner diameter is set so that the anchor 2 and the peripheral surface of the through hole 4b'do not come into contact with each other.

Here, the axis L is set based on the angle of intersection between the assumed anchor 2 and the bottom surface 4d of the main body 4 of the pressure receiving plate 3 from the situation of the slope S of the ground where the pressure receiving plate 3 is installed. However, the actual angle β may deviate from the assumed crossing angle by several degrees (about ± 2.5 °) depending on the state of the slope S at the time of installation. However, the inner diameter of the through hole 4b'is set so that the anchor 2 does not come into contact with the peripheral surface of the through hole 4b'.

Similarly, if the angle γ formed by the bottom surface 4d of the main body 4 and the axis L of the insertion hole 22c'is 95 ° and the angle β is in the range of 95 ° ± 2.5 °, the insertion hole 22c'is The inner diameter is set so that the anchor 2 and the peripheral surface of the insertion hole 22c'do not come into contact with each other.

Further, FIG. 6 is an enlarged view similar to FIG. 4, showing a second modification of the main body portion 4 of the pressure receiving plate 3 and the receiving pedestal 20. In this modification, the same elements as those in the above embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in the figure, in this modification, the configurations of the through hole 4b ″ of the main body 4 and the insertion hole 22c ″ of the pedestal 20 are different from those of the above embodiment.

Specifically, in this modification, the through hole 4b'' has an angle γ formed by the bottom surface 4b of the main body 4 and the axis L of the through hole 4b'' of 100 °, and the angle β is 100 ° ±. Within the range of 2.5 °, the inner diameter is set so that the anchor 2 and the peripheral surface of the through hole 4b ″ do not come into contact with each other.

Similarly, in the insertion hole 22c'', the angle γ formed by the bottom surface 4d of the main body 4 and the axis L of the insertion hole 22c'' is 100 °, and the angle β is in the range of 100 ° ± 2.5 °. If there is, it is set to have an inner diameter such that the anchor 2 and the peripheral surface of the insertion hole 22c ″ do not come into contact with each other.

Here, when the angle β formed by the bottom surface 4b of the main body 4 and the anchor 2 deviates significantly from the vertical to 95 ° (first modification) and 100 ° (second modification), the through hole of the main body 4 or The angle β of the insertion hole of the pedestal 20 is 82.5 ° to 97.5 ° (including the case where the lower limit is further shifted by 2.5 ° from the lower limit of 85 ° and the case where the upper limit is further shifted by 2.5 ° from 95 °), 77.5. The pedestal has a tapered shape that can cover the entire range from ° to 102.5 ° (including cases where the lower limit is further deviated by 2.5 ° and cases where the upper limit is further deviated from 100 ° by 2.5 °). The area of the outer surface 22a of the bottom wall portion 22 which is the load transmission surface of the 20 is insufficient, a large space is created in the lower region of the pedestal 20, and the main body 4 of the pressure receiving plate 3 is damaged at the lower part of the pedestal 20. There was a risk of doing so.

According to the first modification and the second modification of the load transmission portion structure 10 from the anchor and the pressure receiving plate 3 of the present invention, the through hole of the main body portion 4 and the insertion hole of the pedestal 20 correspond to the angle β. The hole has a substantially cylindrical shape, and the pedestal 20 and its lower region can be formed densely, and the load on the lower region of the pedestal 20 where stress tends to be concentrated can be accurately dispersed.

Further, by properly using the three patterns of the above embodiment, the first modification, and the second modification, the possible angle β between the anchor 2 and the bottom surface 4d of the main body 4 can be set to 87.5 ° to 102.5 °. It can be adjusted within the range of, that is, within the range of 15 °. This range of 15 ° almost coincides with the range of 90 ° to 105 ° assumed as the range of the angle β, whereby the range that the angle β can take can be almost covered.

Here, according to the first modification and the second modification of the load transmitting portion structure 10 from the anchor of the present invention and the pressure receiving plate 3, it is decided to cover the range 90 ° to 105 ° that the angle β can take. It is also possible to set the angle γ to 4 steps (90 °, 94 °, 98 °, 102 °) instead of 3 steps (90 °, 95 °, 100 °) as in. That is, the pressure receiving plate is prepared in advance so as to be able to cope with the case where the angle (angle β) between the anchor and the bottom of the main body of the pressure receiving plate is within a predetermined range (for example, in the range of 90 ° to 105 °). It may be selected from a plurality of pressure receiving plates having different crossing angles (angles γ). According to this, the range of each β can be adjusted in the range of ± 2 ° (90 ° ± 2 °, 94 ° ± 2 °, 98 ° ± 2 °, 102 ° ± 2 °), from 88 ° to The range of 16 ° of 104 ° can almost cover the range that the angle β can take.

Further, the fact that the angle γ is in the above three steps or four steps means that a large amount of standard products of the pressure receiving plate 3 in which the angle between the bottom surface 4d of the main body 4 and the insertion hole of the main body 4 is set in three steps or four steps. It means that production is possible. It should be noted that the fact that the angle γ has the above three stages and four stages is merely an example, and the angle γ may be set in multiple stages within the range in which the present invention can be carried out.

According to the first modification and the second modification, the through holes 4b'and 4b'' have a substantially cylindrical shape and do not have a tapered shape that expands downward, so that the angle β is large from 90 °. Even if it is displaced (for example, if it is displaced by 5 ° or more), the waterproof plug 26 easily adheres to the peripheral wall surface of the through holes 4b'and 4b', and the waterproofness inside the through holes is maintained more reliably. can do.

Further, in the above embodiment, the anchor head 12 is configured as a combination of the upper connecting member 13 and the bottom member 14, but the present invention is not limited to this case.

FIG. 6 is a cross-sectional view similar to FIG. 1 (B) showing a modified example of the anchor head 12. As shown in the figure, in this modification, the anchor head 30 has a bottom outer surface 30a having a convex spherical surface, a columnar side peripheral surface 30b, a flat top surface 30c, and a flat top surface 30c to the outside of the bottom. It is configured as one member having an anchor hole 30d penetrating to the side surface 30a.

Even in this modification, the optimum angle between the bottom surface 4d of the pressure receiving plate 3 and the anchor 2 is optimized by the interaction between the convex spherical surface of the bottom outer surface 30a and the concave spherical surface of the inner surface 22b of the bottom wall portion 22 of the pedestal 20. The effect of the present invention can be exhibited, that is, the load is accurately distributed through the outer surface 21a of the side wall portion 21 of the pedestal 20.

Further, FIG. 7 is a cross-sectional view similar to FIG. 1 (B) showing a further modification example of the anchor head 12. As shown in the figure, in the present modification, the anchor head 40 is a combination of the upper connecting member 13 of the present embodiment, the flat plate-shaped conventional anchor plate 44, and the side view substantially convex lens-shaped bottom member 46. May be.

Here, the bottom member 46 has a convex shape having substantially the same curvature with respect to the top surface in surface contact with the bottom surface of the anchor plate 44 and the concave spherical surface of the inner side surface 22b of the bottom wall portion 22 of the pedestal 20. It has a bottom outer surface 46b having a spherical surface of the above. Thereby, the effect of the present invention can be exhibited only by adding the bottom member 46 to the combination of the conventional coupling member 13 and the anchor plate 44.

Further, in the present embodiment, the anchor head 12 has been described as including an anchor head coupled to the upper end portion 2a of the anchor 2, but the anchor head 12 is not limited to the embodiment in which the anchor head of a member different from the anchor is coupled. .. That is, the anchor head may be placed on the pedestal 20 as long as it can be placed on the pedestal. It may form a head.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention.

For example, in the above embodiment, the wedge 15 is exemplified as a connecting means for connecting to the upper end portion 2a of the anchor 2, but the present invention is not limited to this. For example, a male screw may be cut on the upper end portion 2a of the anchor 2, and a bolt having a female screw corresponding to the male screw may be adopted as the coupling means.

1 Slope stabilization system 2 Anchor 3 Pressure receiving plate 4 Main body 4b, 4b', 4b''Through hole 10 Load transmission part structure from anchor to pressure receiving plate 12 Anchor head 13 Top connecting member 14,46 Bottom member 14b, 46b Bottom outer surface (outer surface)
15 Wedge (joining means)
20 Receiving pedestal 21 Side wall 22 Bottom wall 22b, 22b', 22b'' Insertion hole

Claims (5)

An anchor that has a head at the upper end and is buried in the slope of the ground with at least the head exposed.
It has an insertion hole through which the anchor is inserted, and has a pedestal on which the head of the inserted anchor is placed and a recess formed so that the pedestal can be fitted on the upper surface of the anchor. A pressure receiving plate having a main body portion that receives a tension force on a mountain via the receiving pedestal and being pressed and installed on the slope.
In the load transfer structure from the anchor to the pressure receiving plate in the slope stabilization system
The pedestal is
It has a bottomed truncated cone shape that tapers toward the ground in the pressed installation state of the pressure receiving plate, and has an inclined side wall portion formed by hollowing out the inside and a bottom wall portion continuous with the side wall portion. death,
An insertion hole through which the anchor is inserted is provided in the bottom wall portion.
At least the compressive strength is set to be larger than that of the main body of the pressure receiving plate.
The inner surface of the bottom wall is formed as a concave spherical surface extending to at least a part of the inner surface of the side wall.
The bottom outer surface of the anchor head mounted on the pedestal is formed as a convex spherical surface having substantially the same curvature as the concave spherical surface of the pedestal.
A load transmitting portion structure from an anchor to a pressure receiving plate, characterized in that the extending region of the concave spherical surface is larger than the region of the convex spherical surface . The insertion hole of the pedestal and the through hole through which the anchor penetrates in the main body of the pressure receiving plate are the anchor and the main body of the pressure receiving plate when the pressure receiving plate is pressed and installed on the slope of the ground, respectively. The load transmitting portion structure from the anchor to the pressure receiving plate according to claim 1, wherein the hole is provided as a substantially cylindrical hole extending in a position and a direction corresponding to an assumed crossing angle with the bottom surface of the surface. The pressure received from the anchor according to claim 1 or 2, wherein the angle formed by the outer surface of the side wall portion of the pedestal and the outer surface of the bottom wall portion of the pedestal is 55 ° or more and 65 ° or less. Load transmission part structure to the plate. Claims 1 to 3 are characterized in that the anchor head is a combination of an upper connecting member having a means for connecting to an upper end portion of the anchor and a bottom member having the outer surface which is a convex spherical surface. The load transmission unit structure from the anchor to the pressure receiving plate according to any one of the above items. The load transmitting portion structure from the anchor to the pressure receiving plate according to any one of claims 1 to 4, wherein the upper end portion of the anchor is made of a PC steel wire.

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