JP4117216B2 - Pressure plate for ground anchor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressure receiving plate used for a ground anchor work as a slope stabilization countermeasure work, and more particularly to a structure that enables on-site construction.
[0002]
[Prior art]
In the ground anchor work as a slope stabilization countermeasure work, a precast pressure receiving plate is often used because the construction period can be shortened and a relatively large anchor tension can be applied. As a method for producing the pressure receiving plate, a mold (form) is manufactured in advance, concrete is poured into the mold, and the product is manufactured by removing the mold after solidifying the concrete. The cost of manufacturing the mold is high, and therefore the pressure plate that can be used is limited to a plurality of types, and an optimum size can be selected from among them.
[0003]
[Problems to be solved by the invention]
If there are no optimal dimensions, it will be necessary to select one size larger than the size and weight essential for construction, resulting in excessive quality, as well as larger size and weight per pressure plate. There is a drawback that the unit price, the cost for transportation, and the installation become high, and the construction price becomes expensive as the number of used units increases. In addition, since the bottom surface of the precast pressure receiving plate is flat, it cannot be installed unless the corresponding slope is cut or embanked to level the ground, and the leveling work is not easy.
Therefore, the present invention solves the above-described problems, and provides an on-site construction type ground anchor pressure receiving plate in which an optimum size pressure receiving plate can be easily constructed on site.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an annular metal plate that borders the outer shape of the pressure receiving plate, and a metal fitting for inserting a main body of a ground anchor that is connected to the metal plate at the inner center portion of the metal plate. A cloth mold frame having a center connected to the top of the metal fitting for insertion, a peripheral edge of the metal plate being fastened to the outer peripheral portion of the metal plate by a binding means and tensioned by a predetermined tension, and closing the upper opening of the metal plate, It is characterized by being made of a solidified material such as concrete that is injected into the enclosed interior and integrates each part.
[0005]
Therefore, the pressure receiving plate of the present invention can function as a discarded form frame in which a metal plate such as an iron plate or a metal fitting for insertion is integrated into a solidified material as a steel frame. In addition, the cloth functions as a waste mold for preventing the solidification material filled therein from overflowing as well as degassing and defoaming of the solidification material. The above metal plates and hardware can be assembled in advance by welding, etc., transported to the site, covered with cloth, and then integrated with each other by placing solidified material, so that transport and installation work can be done in a lightweight state. . Further, when installing, even if there are irregularities on the inclined surface, it can be adapted to the irregularities by placing the solidifying material, so that no leveling work is particularly required.
[0006]
In the invention according to the second aspect of the present invention, by providing the solidifying material injection port penetrating the inside and outside of the metal plate, the solidifying material can be easily placed inside the mold.
[0007]
In the invention according to claim 3 of the present invention, the strength of the solidified material in the molded state is improved by connecting the metal plate with the metal plate directly below the top of the insertion metal fitting.
[0008]
In the invention according to the fourth aspect of the present invention, in addition to the invention according to the third aspect, the strength of the solidified material can be further increased by providing a plurality of horizontal bars crossing the reinforcing bars.
[0009]
In the invention according to claim 5 of the present invention, by providing a wire mesh that covers the upper surface of the cloth mold frame and a plurality of fixing metal fittings for fixing the wire mesh to the cloth surface, the solid material is driven by the placing pressure. Since the swelling of the cloth can be prevented, the outer shape can be maintained with high accuracy.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 to 3 show a pressure receiving plate according to a first embodiment of the present invention and a production procedure in the field. FIGS. 1 and 2 show the framework. The pressure receiving plate 1 has an annular iron plate 2 made of a metal such as a thin steel plate constituting the outer shape of the discarded mold frame, and a cross in the iron plate 2 in a cross shape. H-shaped steel 3 as a reinforcing steel frame disposed inside the steel plate 2 by welding or the like, a disk-shaped flange 4 integrated by welding on the cross-center upper surface of the H-shaped steel 3, a flange 4 and An uncurtain dong or a lock bolt (hereinafter referred to as an anchor main body), which is a main body of a ground anchor integrated through the crossing center of the H-shaped steel 3 vertically, is provided.
[0011]
A part of the iron plate 2 is provided with a concrete injection port 6 penetrating the inside and outside of the iron plate 2, and a concrete hose is connected to the concrete injection port 6 to enable concrete injection. Further, an L-shaped section 7 as a binding means is disposed on the upper side of the outer periphery of the iron plate 2 so as to be able to expand and contract. The web of each said H-shaped steel 3 is formed with a hollow hole 3a to secure the wraparound property and the biting property of the concrete.
[0012]
The insertion hardware 5 is integrated with an inclination of about 5 ° with respect to the vertical, and the anchor insertion small-diameter cylindrical portion 8 projecting at the lower portion of the H-section steel 3 and the cylindrical portion 8 A seat plate 8a to which a fixing metal for fixing the tip of an anchor (indicated by an imaginary line in FIG. 2) which is integrated at the upper portion and protrudes from the cylindrical portion 7 is joined, and is integrally installed around the seat plate 8a. A large-diameter cylindrical portion 9 with an open top surface, a flange 10 integrated with the peripheral edge of the top portion of the cylindrical portion 9, and a lid portion 12 integrated with a flange 11 coupled to the flange 10 at the peripheral edge. 11 are detachably connected via a plurality of bolts 14.
[0013]
In addition, a plurality of reinforcing bars 15 are arranged radially by connecting the peripheral edge of the large-diameter cylindrical portion 9 directly below the flange and the inner side of the iron plate 2, and both ends are fixed by welding or the like. The horizontal bars 16 are arranged concentrically and are connected to the reinforcing bars 15 by a binding wire (not shown). The metal 7 is divided into four parts in the circumferential direction at intervals of 90 °, for example, and these four parts are joined together by bolts and nuts 17 so as to be loosened.
[0014]
The frame structure of the above-mentioned discarded formwork is pre-manufactured at an iron factory or the like based on the design of required dimensions and strength at the construction site, and is placed around the ground projecting end of the anchor body at the site and covered with the cloth formwork 18 It functions as a discarded formwork.
[0015]
3 (a) and 3 (b) show the assembling procedure. First, as shown in FIG. 3 (a), the lid 12 is removed, and the center part of the cloth mold frame 18 whose center part and peripheral part are cut into a circle are shown. Is placed on the flange 10, and the edge of the cloth 18 mold is inserted between the iron 7 and the iron plate 2 in a state where the screw 7 is loosened. Next, the lid portion 12 is attached to the opening portion of the tube portion 9, and the bolts and nuts 14 are tightened to fix the upper end of the cloth 18.
[0016]
Next, the peripheral edge of the cloth mold 18 is pulled with sufficient tension, and while holding the predetermined tension, a wrench or the like as shown in an enlarged view of the bolt nut 17 connecting the seven members 7 is shown in a part of the figure. When used and tightened, the diameter of 7 is reduced, and as shown in (b), the discarded formwork is completed with the periphery of the cloth formwork 18 tightly fixed.
Thereafter, a valve 19 is attached to the concrete injection port 6 and concrete is injected into the interior as shown by an arrow through a hose (not shown) to complete the substantially conical pressure receiving plate 1 in which the respective parts are integrated. Become.
[0017]
The cloth material used as the cloth mold 18 is, for example, a glass cloth of a predetermined mesh which is a molding material of FRP, and the concrete placed inside the discarded mold is being deaerated through the cloth mold 18. The interior surrounded by the cloth mold 18 and the iron plate 2 is filled, and the filling is completed in a state where water in the concrete oozes out on the surface of the cloth 18 and is integrated with the surface of the cloth 18 by solidification.
The lid 12 is detachable even after completion, and can fix the anchor body projecting into the interior of the pressure receiving plate 1 after the pressure receiving plate 1 is constructed.
[0018]
FIG. 4 shows a ground anchor construction in which the pressure receiving plate 1 by the above-described construction on the ground is integrated with the ground surface portion. In the figure, a hole 21 is formed in an inclined ground 20, and an anchor main body 23 is embedded and fixed through a grout 22.
The tip of the main body 23 protrudes from the ground surface of the ground 20, and after the pressure receiving plate 1 is constructed with the protruding end inserted into the small diameter cylindrical portion 8, the ground surface protruding end of the main body 23 is placed inside the insertion hardware 5. By fixing in the above, a substantially constant bearing stress acts between the bottom surface of the pressure receiving plate 1 and the ground 20, and the tension of the anchor can be efficiently transmitted to the ground surface over the entire surface of the pressure receiving plate 1. Become.
[0019]
In addition, when the pressure receiving plate 1 is applied to the above-described slope, if the axis of the main body 23 and the axis of the insertion metal fitting 5 coincide, even if there is some unevenness, the concrete is in the finished state. The ground is filled, and stress can be transmitted over the entire surface, so that leveling is unnecessary.
[0020]
FIG. 5 shows a second embodiment of the present invention. In the figure, the entire surface of the cloth mold 18 is covered with a shape-maintaining wire mesh 30 such as expanded metal or punching metal, and the wire mesh 30 is pressed against and fixed to the cloth surface by a plurality of presser fittings 31. The same as in the first embodiment.
Although not shown in the figure on the mold side corresponding to the presser fitting 31, it is possible to attach the presser fitting 31 by fixing the receiving metal fitting along the presser fitting 31.
[0021]
In this embodiment, since the outward expansion of the cloth 18 due to the concrete placing pressure is prevented, the outer shape of the tapered surface at the time of molding can be accurately adjusted. Further, the wire mesh 30 and the presser fitting 31 can be removed after the pressure receiving plate 1 is formed and can be diverted for forming another pressure receiving plate 1.
[0022]
In each of the embodiments described above, although 7 is used as the binding means, which can be expanded and contracted by tightening and loosening the bolts and nuts, it is needless to say that a high-strength binding tape for packing or the like can be substituted.
[0023]
【The invention's effect】
As is apparent from the above description, according to the pressure receiving plate for ground anchor according to the present invention, the pressure receiving plate of the optimum size can be easily constructed on site, and the construction cost is lower than when a conventional precast pressure receiving plate is used. Can be.
[Brief description of the drawings]
FIG. 1 is a plan view showing a framework of a discarded formwork of a pressure receiving plate according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional side view of the same.
FIGS. 3A and 3B are perspective views showing a partially enlarged portion showing a procedure for attaching a cloth to the frame structure. FIGS.
FIG. 4 is a side sectional view showing a ground anchor construction using the pressure receiving plate.
FIG. 5 is a perspective view showing another embodiment at the time of molding the pressure receiving plate.
[Explanation of symbols]
1 pressure receiving plate 2 annular steel plate 3 H-section steel (reinforced steel frame)
5 Ground anchor insertion hardware 6 Concrete injection port 7
15 Reinforcing bar 16 Horizontal bar 23 Anchor main body 30 Shape retaining wire mesh 31 Presser fitting

Claims (5)

An annular metal plate that borders the outer shape of the pressure receiving plate, and a metal fitting for inserting the main body of the ground anchor that is connected to the metal plate at the inner center portion thereof, and a center is connected to the top of the metal fitting for insertion. The peripheral edge of the metal plate is fastened to the outer peripheral portion of the metal plate by a predetermined tension and is stretched by a predetermined tension. A pressure receiving plate for a ground anchor, comprising a solidified material such as concrete to be integrated. The pressure receiving plate for a ground anchor according to claim 1, wherein a solidifying material injection port penetrating the inside and outside of the metal plate is provided. The pressure receiving plate for a ground anchor according to claim 1 or 2, wherein a plurality of reinforcing bars are arranged radially by connecting a metal plate and a portion directly below the top of the insertion metal fitting. The pressure receiving plate for a ground anchor according to claim 3, wherein a plurality of transverse bars are provided so as to cross each of the reinforcing bars. The pressure receiving plate for a ground anchor according to any one of claims 1 to 4, further comprising: a metal mesh that covers an upper surface of the cloth mold frame; and a plurality of fixing brackets for fixing the metal mesh to the cloth surface. .

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