JP3466538B2 - Pressure plate for anchor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure receiving plate for an anchor which is installed on an inclined ground and fixed by an anchor member to stabilize the inclined ground. 2. Description of the Related Art In order to stabilize an inclined ground, a retaining wall is fixed to a target ground with an anchor member such as an anchor cable. Conventionally, a retaining wall (hereinafter referred to as a pressure receiving plate) has a P
C-pressure receiving plate, RC pressure-receiving plate, pressure-receiving plate made of cast or steel plate made of fitting type, square resin plate laminated in pyramid type, which is tentatively installed after only temporarily installed with RC type rebar, and then tensioned when strength is developed. Plate (Japanese Unexamined Patent Publication No. 9-71)
No. 941). Each of the pressure receiving plates has a basic structure in which a center hole through which an anchor member such as an anchor cable is inserted is formed in a central portion, and a bottom plate portion constituting a pressure receiving surface is continuously provided around the central portion. . The bottom plate portion may be of a flat plate shape or of a plurality of arms having a rectangular or semi-cylindrical cross-sectional shape arranged radially. [0005] In the PC-type or RC-type pressure receiving plate, a center hole is provided in the protrusion, and an anchor head fixed to the outer end of the anchor member is provided above the protrusion. However, since the cross-section viewed from the side has a cross-sectional defect due to bending stress, the thickness of the protrusion must be increased to obtain the required strength. , There are complaints that the cost is high. In addition, since the height of the projections is high due to the concrete strength, a large amount of soil is necessary to bury the whole, and even if buried in seed soil for greening, the arm made of concrete will not There is also a problem that it is not greened. [0006] Further, in the case of a pressure receiving plate for an anchor made of a normal casting, since the manufacturing cost is proportional to the weight, the pressure receiving plate tends to be more expensive than the pressure receiving plate of another manufacturing method. In addition, the structure that lowers the bending strength of the center hole part and protrudes the anchor head upward without providing a storage part that is disadvantageous in terms of cost compared to other types of pressure receiving plates with storage parts There is a problem that is inferior. In the case of a concrete pressure receiving plate or a steel pressure receiving plate having a cross shape or the like formed by a plurality of arms, the cross section of the arm has a simple square cross section or a semi-cylindrical shape, and the upper surface is smooth. , The seed soil is hard to adhere, and the arm cannot be greened. Further, if the steel pressure receiving plate is inadequate for rust prevention and waterproofing, when buried in seed soil, there is a problem that the corrosion progresses quickly and the strength cannot be maintained for a long time. The point of this corrosion is described in JP-A-9-71.
Even if a rib is provided as in the pressure receiving plate of No. 941, there is no change, and the strength cannot be maintained for a long time. An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a pressure receiving plate for an anchor which has excellent strength and is hardly corroded. Another object of the present invention is to provide a pressure receiving plate for an anchor that requires a small amount of buried soil and has high holding power for seed soil. Another object of the present invention is to provide a pressure receiving plate for an anchor which can reduce the cost per required strength. [0009] In order to achieve at least one of the above-mentioned objects, according to the first aspect of the present invention, a center hole through which an anchor member is inserted is formed in a center portion, and the center hole is formed in the center portion. The pressure receiving plate for an anchor, in which the bottom plate portion constituting the pressure receiving surface is continuously provided, is entirely made of ductile casting. In this means, the following characteristics of the ductile casting (including the ductile alloy casting) are utilized. (A) Although the surface is rusted, corrosion hardly progresses extremely inside. (B) Despite the large tensile force, the compressive force is about three times greater than the tensile force compared to other steel materials (2 to 5 times depending on the ratio of the ferrite structure to the pearlite structure).
Times). For this reason, the part receiving stress is made thicker than a certain thickness in consideration of the progress of corrosion, and the cross-sectional area of the part where the tensile force acts is large, and the part where the compressive stress acts is correspondingly reduced in weight. It becomes possible. Further , the bottom plate portion is constituted by a plurality of arms connected radially around a central portion, and on the upper surface of each arm, a stress rib along a length direction of the arm and intersects the stress rib. A reinforcing hole, and a center hole is provided on a protrusion projecting from the upper surface of the central portion, and an anchor head fixed to the outer end of the anchor member is fitted and stored on the protrusion. Set up a hemispherically shaped storage
I am. In this configuration, the stress rib and the reinforcing rib enhance the strength of the arm. In addition, since these ribs hold the seed soil to prevent runoff, the slope can be efficiently greened. Stress ribs and reinforcement ribs stabilize the buried soil,
When the buried soil becomes stable, the role ends. Therefore, since both ribs are allowed to disappear by corrosion in the long term,
The thickness can be reduced as long as there is no problem in forming the casting. actually,
Due to the above characteristics of the ductile casting, even if it is a thin rib, its surface is rusted but does not corrode inside. Also, on the upper surface of the central portion ,
A stress rib linearly connected to the stress rib is provided in communication with the projection. [0014] In this configuration, the projection at the center where the center hole is formed is a cross-sectional defect that is easily buckled.
Since the anchor head fitted and accommodated in the accommodating portion bridges and receives the compressive force applied to the protruding portion, there is no cross-sectional defect. Embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 4 show an embodiment of an anchor pressure receiving plate according to the present invention. This anchor pressure receiving plate is made of a ductile casting (including a ductile alloy casting), and has four arms 2 provided radially around a central portion 1 at equal intervals. On the upper surface of the central portion 1, one protrusion 1a and four stress ribs 1b and 1c are provided to project at the same height. A center hole 1d and a storage portion 1e are formed in the protrusion 1a, and the stress ribs 1b are radially connected around the protrusion 1a at regular intervals, and the other stress ribs 1c are formed.
Are formed in a square shape by connecting the outer end of each stress rib 1b to a corner. Here, the center hole 1d of the projection 1a
Is for inserting an anchor member 5 such as an anchor cable, and the storage part 1e is for fitting and storing an anchor head 7 fastened to the outer end of the anchor member 5 by a fastening tool 6 such as a wedge piece. Is what you do. The storage portion 1e is formed in a hemispherical shape above the projection 1a so as to communicate with the center hole 1d, and the hemispherical anchor head 7 is also formed.
Is free to rotate. Each arm 2 is formed in a tapered flat plate shape.
On its upper surface, a stress rib 2a for receiving bending stress and a reinforcing rib 2b functioning as a partition are projected. The stress rib 2a has its inner end connected to the corner of the stress rib 1c, 1c and is provided at the center of the arm 2 along the length direction of the arm 2. The reinforcing rib 2b is connected to the stress rib 2a. They are connected in an orthogonal state and provided in the width direction of the arm 2. The stress ribs 2a are inclined downward from the inner end portion having the same height as the stress ribs 2c toward the tip of the arm 2. Each reinforcing rib 2b has the same height as the height of the connecting portion of the stress ribs 2a. Have been. The stress ribs 1b and 2a are connected linearly via a stress rib 1c. The four arms 2 constitute a bottom plate portion. According to the above construction, the surface is rusted, but the corrosion hardly progresses inside, and in addition to the large tensile force, the characteristic of the ductile casting having a compressive force that is about 2 to 5 times larger than that of steel is produced. As a result, a strong pressure receiving plate for an anchor is obtained. Further, the cross-sectional shape of the arm 2 is mountain-shaped by the stress ribs 2a and the reinforcing ribs 2b, and the required strength can be obtained with a minimum cross-sectional area. Moreover, the buckling of the protrusion 1a is prevented by the anchor head 7 fitted and stored in the storage portion 1e. Further, since the ribs 2a and 2b having the mountain-shaped arrangement stably hold the seed soil, the entire slope can be greened. Further, since surface treatment for anticorrosion is not required, the anticorrosion performance is not reduced by contact friction or the like which is likely to occur during transportation. Since a core is not required at the time of casting the above-mentioned chevron cross section, the cost can be further reduced. As a result, the following effects can be obtained as compared with the prior art. (B) Significant expansion of the area that can be greened. (B) Reduce the amount of sprayed seed soil by suppressing the height of the pressure receiving plate. (C) Cost reduction per required strength. (D) Improving transportation efficiency, corrosion stability, and manufacturing costs by eliminating corrosion protection. Conventionally, a mold was prepared each time the pressure receiving area was changed. However, if it is supposed to be buried, even if a haunch (overhang) is provided on the bottom plate that is completely hidden, it can be hidden by seed soil. There is no need to arrange them, and a single mold can be used, so that the mold cost can be suppressed. Similarly, the corresponding load can be changed by changing the height while sharing the mold. In the present invention, the arm 2 and the stress rib 1
The numbers and shapes of b, 1c, 2a and the reinforcing ribs 2b are not limited to those shown in the drawings, but are arbitrary, and various design changes can be made.
In some cases, the bottom plate portion may be a flat plate such as a square, a polygon, or a circle. In addition, the distance between the tips of the two arms 2, 2 which are linearly arranged on the anchor pressure receiving plate shown in the figure is 2.5 m, the height of the projection 1a is 40 cm, and the height of the tip of the arm 2 is 20 cm. However, it is needless to say that the size is not limited to this. As described above, according to the first aspect of the present invention, the pressure receiving plate for an anchor having excellent strength and corrosion resistance can be provided to the market by utilizing the characteristics of the ductile casting. it can. Further , the bottom plate portion is constituted by a plurality of arms connected radially around the central portion, and on the upper surface of each arm, a stress rib extending along the length direction of the arm and intersecting the stress rib. A reinforcing hole, and a center hole is provided on a protrusion projecting from the upper surface of the central portion, and an anchor head fixed to the outer end of the anchor member is fitted and stored on the protrusion. the is provided with a housing portion of the semi-spherical
Thus, the cost per required strength can be reduced, and the height can be reduced by strengthening the strength, so that the amount of buried soil can be reduced. Further, since the seed soil is held by the stress ribs and the reinforcing ribs, the slope can be efficiently greened. Further, a stress rib is formed on the upper surface of the central portion to form a projection.
Since it is provided in contact, the anchor head can be utilized to eliminate a cross-sectional defect and prevent buckling of the projection.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an external view showing an embodiment of an anchor pressure receiving plate according to the present invention. FIG. 2 is a plan view of the anchor pressure receiving plate of FIG. 1; FIG. 3 is also a side view. FIG. 4 is a cross-sectional view of a projection at the center. [Description of Signs] 1 Central portion 1a Projection portion 1b, 1c Stress rib 1d Center hole 1e Storage portion 2 Arm 2a Stress rib 2b Reinforcement rib 5 Anchor member 6 Fastener 7 Anchor head

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E02D 17/20 103 E02D 5/74 E02D 5/80

Claims (1)

(57) [Claim 1] A center hole through which an anchor member is inserted is formed in a center portion, and a pressure plate for an anchor, in which a bottom plate portion forming a pressure receiving surface is continuously provided around the center portion. In the above, the whole is made of ductile casting, and the bottom plate portion is constituted by a plurality of arms connected radially around a central portion, and on the upper surface of each arm, a stress rib along the length direction of the arm, Reinforcing ribs intersecting with the stress ribs are provided, respectively, and the center hole is provided on a protrusion projecting from the upper surface of the central portion, and is fixed to an outer end of the anchor member on the protrusion. accommodating portion formed the anchor head in a hemispherical shape to be fitted housing is provided on the upper surface of the central portion, the stress ribs and straight the arm top
A pressure receiving plate for an anchor, wherein a connected stress rib is provided so as to communicate with the projection.