JP7217515B2 - Slope protection structure and slope protection method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a slope protection structure and a slope protection method, and more particularly to a slope protection structure and a slope protection method in which a frame for stabilizing a slope is installed.

Conventionally, various slope protection techniques have been developed and put into practical use in order to prevent slope failures and landslides of natural ground.

As a construction method for slope protection, a grid-like formwork is installed on the slope and concrete is poured into the formwork, such as the cast-in-place method, or to eliminate the need to dismantle the formwork. The method of burying the entire slope by spraying mortar or concrete onto the formwork installed on the slope is widely used.

In addition, as shown in FIGS. 15A and 15B, a method of constructing a lawn frame in which a grid-like lawn frame 12 and an anchor 13 are combined is also constructed. In this slope construction method, anchors 13 whose tips reach the stable stratum G are driven at intersections of grid-like slopes.

However, as shown in FIG. 15(A), when the slope 12 deteriorates due to weathering and cracking over time, it is feared that the strength at the time of design cannot be maintained and the strength becomes insufficient.

In order to resolve the lack of strength of the legal framework, it is conceivable to remove the existing legal framework and install a new legal framework. Therefore, there is a need for a method that can provide additional protection to the slope without removing the slope.

As a protective work that can solve the lack of bearing strength of the law frame without removing the existing law frame, for example, in the area of the slope where the grid-like frame member constituting the law frame is not arranged, Patent Document 1 The method of providing the described pressure plate is conceivable.

The pressure receiving plate described in Patent Document 1 is a plate material made of cast iron, and is fixed to the head of an anchor extending from an unstable layer G2 forming the surface layer of the slope to a stable layer G1 in the ground. press. This pressure plate can be installed in each frame of the law frame formed in a grid pattern.

JP-A-11-158877

However, the protection work described in Patent Document 1 is a structure that reinforces with a newly driven anchor and a pressure plate fixed to its head, and the existing law frame itself cannot be reinforced. There was a demand for the development of a slope protection structure with excellent durability while enhancing the slope protection performance of the slope.

The present invention has been made in view of the above-mentioned problems, and is capable of effectively protecting a slope by enhancing the slope protection performance of the slope on which the slope is installed, and having excellent durability. The purpose is to provide a slope protection structure and slope protection method.

In order to achieve the above object, the invention method described in claim 1 is
In the protective structure of the slope where the law frame for slope stabilization is installed,
a plurality of anchors placed at intervals in a non-existing area of the law frame within the setting range of the law frame;
A plate-shaped underlay material arranged on the slope and through which the anchor penetrates;
a net body composed of a rhombic wire net laid on the slope from above the law frame;
a plate member that is attached to the head of the anchor and applies tension to the net body by pushing down the net body to a position lower than the height position of the top surface of the law frame;
a cylindrical spacer disposed between the underlay material and the plate material and surrounding the outer circumference of the anchor ;
The wire material constituting the net body is a wire material made from a hard steel wire material, and has a zinc plating layer or a zinc aluminum alloy plating layer with an adhesion amount of 80 g / m ² or more on the surface,
The spacer has a tubular main body and a flange protruding radially outward from an outer peripheral surface of an axially intermediate portion of the main body,
the flange portion abuts on the upper surface of the underlaying material, the lower end portion of the main body portion penetrates the underlaying material and extends toward the ground;
The inside of the main body is filled with a grout material .

According to this configuration, the net is laid on the slope from above the slope, and is pushed down to a position lower than the height of the top surface of the slope by the plate material fixed to the head of the anchor. , the slope is in a state of being pressed by the net through the slope. As a result, the slope protection performance of the slope frame is enhanced, and slope failure can be prevented by pressing down the slope area where the slope frame is not placed from above with a net, and the slope can be effectively protected. can.

In addition, since the rhombic wire mesh that constitutes the mesh is composed of wire materials made from hard steel wire rods, it is less likely to be plastically deformed than iron wires made of commercially available mild steel wires, and has high tensile strength and spring properties. have In addition, a zinc plating layer or a zinc aluminum alloy plating layer is formed on the surface of the net body, and the adhesion amount is 80 g / m ² or more, so that the net body can be laid over the slope frame and Even under conditions where the frame rubs against each other, it is possible to maintain the anti-corrosion performance of the mesh and provide a structure with excellent durability.

In addition, according to this configuration, the spacer can make an appropriate difference between the height position of the top surface of the lawn frame and the height position of the net pushed down by the plate member. Further, by filling the inside of the spacer with a grout material, it is possible to prevent the head of the anchor protruding from the slope from being rusted, thereby enhancing the corrosion resistance.

The slope protection structure according to claim 3 is the slope protection structure according to claim 1 or 2, wherein:
A buffer for wear resistance is provided between the plate material and the net.

According to this configuration, the shock absorber can prevent the net body and the plate material from rubbing against each other to prevent rust from being generated on the surfaces of the net body and the plate material, so that the corrosion resistance can be further enhanced.

The slope protection structure according to claim 4 is the slope protection structure according to any one of claims 1 to 3, wherein:
4. The wire-shaped material constituting the net has a diameter of 2 to 5 mm and a tensile strength of 800 to 2000 N/mm ² . slope protection structure.

According to this configuration, since the net body is made of wire rods made of hard steel wire rods having a tensile strength of 800 to 2000 N/mm ² , the net body is less likely to be plastically deformed, and has high tensile strength and high tensile strength. Spring properties can be exhibited. As a result, it is possible to prevent not only the slope surface portion but also the surface layer slip at a depth of 1 m to 3 m from the slope surface.

The slope protection method according to claim 5,
In a slope protection method in which a slope stabilization frame is installed,
an anchor placing step of placing a plurality of anchors at intervals in a non-existing region of the law frame within the setting range of the law frame;
A net body laying step of laying a net made of a rhombic wire net on the slope from above the law frame;
A plate material installation step of fixing the plate material to the anchor in a state where the net body is pushed down to a position lower than the top surface height position of the law frame by a plate material having a larger diameter than the mesh of the net body. , including
The wire material constituting the net body is a wire material made from a hard steel wire material, and has a zinc plating layer or a zinc aluminum alloy plating layer with an adhesion amount of 80 g / m ² or more on the surface,
In the anchor setting step, a plate-shaped underlay material through which the anchor penetrates is arranged on the slope, and a cylindrical underlay material is arranged between the underlay material and the plate material and surrounds the outer circumference of the anchor. Place a spacer,
The spacer has a tubular main body and a flange provided in an axially intermediate portion of the main body and protruding radially outward from the outer peripheral surface of the main body,
the flange portion abuts on the upper surface of the underlaying material, the lower end portion of the main body portion penetrates the underlaying material and extends toward the ground;
After arranging the spacer, the inside of the main body is filled with a grout material .

According to this configuration, the net is laid on the slope from above the slope, and is pushed down to a position lower than the height of the top surface of the slope by the plate material fixed to the head of the anchor. , the slope is in a state of being pressed by the net through the slope. As a result, the slope protection performance of the slope frame is enhanced, and slope failure can be prevented by pressing down the slope area where the slope frame is not placed from above with a net, and the slope can be effectively protected. can. In addition, even under the condition that the net body is laid on the slope frame and the net body and the slope frame rub against each other, the anti-corrosion performance of the net body can be maintained and the structure can be made excellent in durability.

The slope protection method according to claim 6 is the slope protection method according to claim 5,
It is characterized by including a greening base material injection step of injecting a greening base material between the slope and the net body after the plate material installation step.

According to this configuration, the greening base material injected between the slope and the mesh can green the area where the slope is not installed, thereby preventing the slope surface from being exposed to the wind and rain. outflow can be suppressed.

According to the slope protection structure and the slope protection method of the present invention, the slope protection performance of the slope is enhanced by laying the net on the slope on which the slope is installed. In addition to being able to effectively protect the mesh, the mesh has high anti-corrosion performance and excellent durability.

1 is a plan view schematically showing an embodiment of a slope protection structure according to the present invention; FIG. FIG. 2 is a cross-sectional view along line II-II of the slope protection structure shown in FIG. 1; (A) is a plan view of the mesh, and (B) is a side view of the mesh. The enlarged view of the X section of FIG. A perspective view of a spacer. (A) to (C) are cross-sectional views showing modifications of the spacer. (A) is a perspective view of the plate material as seen from the top side, (B) is a perspective view of the plate material as seen from the bottom side, and (C) is a side view of the plate material. YY line cross-sectional view of FIG. Explanatory drawing of the anchor driving process of the protection method of a slope. Explanatory drawing of the mesh laying process of the protection method of a slope. Sectional drawing which shows the modification of the protective structure of a slope. (A) is a cross-sectional view showing another embodiment of a slope protection structure according to the present invention, and (B) is a plan view of a bag. A sectional view showing another embodiment of a slope protection structure according to the present invention. A plan view schematically showing another embodiment of a slope protection structure according to the present invention. (A) is a perspective view of a slope on which a law frame deteriorated over time is installed, and (B) is a cross-sectional view of FIG. 7(A).

FIG. 1 is a plan view schematically showing an embodiment of a slope protection structure according to the present invention, and FIG. 2 is a cross-sectional view of the slope protection structure shown in FIG. 1 taken along line II-II. In FIG. 2, in order to explain the state of the anchors 13 that fix the slope 12, the side view of the anchors 13 installed at the intersection of the slope 12 is indicated by solid lines. The slope protection structure 10 (hereinafter also simply referred to as the “protection structure 10”) is applied to the slope on which the slope frame 12 is installed, and can reinforce the durability shortage of the existing slope frame 12.

The protective structure 10 includes a slope frame 12 installed on the slope S, a net body 20 installed on the slope frame 12, anchors 14 for fixing the net body 20 to the slope S, an underlay material 16, A plate member 30, a spacer 40 and a cap nut 50 are provided. Underlayment material 16 , plate material 30 , spacer 40 and cap nut 50 are attached to the head of anchor 14 .

As the slope S to which the protective structure 10 is applied, for example, a slope formed by cutting the natural ground can be mentioned. For example, as shown in FIG. 2, the slope S has an unstable layer G2 (surface layer) of 1 m to 3 m, which is easily weathered, and a stable layer G1 (deep layer), which is the stable ground underlying it. A grid-like law frame 12 is provided on the slope S.

As shown in FIG. 1, the lawn frame 12 includes a plurality of vertical frame members 12a extending vertically with respect to the slope S (the vertical direction of the slope S) and a horizontal direction (a direction substantially orthogonal to the vertical direction). It has a plurality of laterally extending frame members 12b which form a lattice-like structure for slope stabilization. In the illustrated example, the intersecting frame members 12a and 12b extend in the vertical and horizontal directions. may extend obliquely with respect to the

The law frame 12 has a substantially square cross-section (substantially trapezoidal shape in the illustrated example) and a substantially flat top surface 12c. It is fixed to the stable stratum G1 by anchors 13 such as rock bolts and ground anchors. In this embodiment, the anchors 13 are driven at the intersections of the grid-like law frames 12 . The distance between adjacent anchors 13 can be, for example, 1 m to 3.5 m. In addition, the cross-sectional shape of the law frame 12 is not limited to a square, and various shapes such as a semicircular shape can be adopted. The cross-sectional size of the lawn frame 2 is, for example, a width w of 150 mm to 400 mm, preferably 150 mm to 300 mm, and a height h of 150 mm to 500 mm, preferably 150 mm to 350 mm.

The net body 20 is laid on the slope 12 so as to cover the entire surface of the slope 12 and is fixed to the slope S by the anchors 14 and the plate members 30 . As shown in FIG. 3A, the mesh body 20 of the present embodiment is a rhombic wire mesh having rhombic meshes 22 . The mesh size of the mesh body 20 is, for example, 50 to 150 mm in diagonal length on one side (shorter mesh in FIG. 3A) and diagonal length on the other side (longer mesh in FIG. 3A). The length can be 50-200 mm.

In this embodiment, the mesh body 20 is formed by weaving metallic wire members 24 . The wire 24 is made of a hard steel wire, has a diameter of 2 mm to 5 mm, preferably 3 mm to 4 mm, and a tensile strength of 800 N/mm ² to 2000 N/mm ² . have As such a linear material, for example, a linear material manufactured from a hard steel wire rod specified in JIS G 3506, such as a galvanized steel wire (JIS G 3548), or the like can be used. The wire material made from hard steel wire is a wire material made from mild steel wire specified in JIS G 3505, that is, an iron wire made of commercially available mild steel wire (generally, tensile strength 290 to 540 N / mm ² It is less likely to be plastically deformed and has high tensile strength and springiness compared to a general-purpose wire mesh made of (a).

The wire-shaped material forming the mesh 20 is not limited to metal. For example, a wire made of carbon fiber, glass fiber, aramid fiber, or the like, or a highly corrosion-resistant resin wire can be used. can. Also, the thickness d of the net body 20 shown in FIG. 3B is preferably three times or more the diameter of the wire member 24, and can be, for example, 10 mm to 30 mm.

The mesh body 20 further has a zinc plating layer or a zinc aluminum alloy plating layer with an adhesion amount of 80 g/m ² or more on the surface. When the plating layer is a zinc plating layer, the coating weight is preferably 100-500 g/m ² , more preferably 200-400 g/m ² . When the plating layer is a zinc-aluminum alloy plating layer, the coating weight is preferably 100-300 g/m ² , more preferably 200-300 g/m ² . The thickness of the plating layer is preferably 14 to 70 μm, more preferably 28 to 42 μm, in the case of the zinc plating layer, and preferably 10 to 50 μm in the case of the zinc aluminum alloy plating layer. , 30 to 48 μm. When the plated layer is a zinc-aluminum alloy plated layer, the zinc content is preferably 85% by mass to 95% by mass, and the aluminum content is preferably 5% by mass to 15% by mass.

Furthermore, the linear members 24 constituting the net body 20 may be coated with a synthetic resin on the surface of the zinc plating layer or the zinc aluminum alloy plating layer, for example, saturated polyester (PET) or polyvinyl chloride (PVC). You may have a coating layer by etc. Thereby, the anti-corrosion property of the net body 20 can be improved more.

The net body 20 is pressed in a direction approaching the slope S by a plate member 30 fixed to the head of the anchor 14 . As shown in FIG. 4, the underlaying material 16, the spacer 40, the plate material 30, and the cap nut 50 are attached to the head of the anchor 14 in this order from the slope S side toward the tip of the head.

As the anchors 14, rock bolts or ground anchors used in the ground anchor construction method can be used. The anchor 14 is located within the installation range of the law frame 12 and in a region where the law frame 12 does not exist (that is, the region of the slope S within the rectangular frame surrounded by the vertical frame members 12a and the horizontal frame members 12b). A plurality of them are placed on the slope S at intervals so as to extend from the ground surface to the stable stratum G1.

The underlay material 16 is a plate-like member and has a through hole formed in the central portion thereof. The underlay material 16 may be, for example, a steel plate whose front and back surfaces are anti-corrosion treated, a steel plate whose front and back surfaces are covered with an FRP layer, or a resin plate in which a reinforcing material is embedded. As shown in FIG. 4, the underlaying material 16 is arranged so that one surface is in contact with the slope S with the heads of the anchors 14 inserted through the through holes.

The spacer 40 is a member arranged between the slope S and the plate member 30 to adjust the separation height of the net body 20 from the slope S. In this embodiment, as shown in FIGS. , is arranged between the underlaying material 16 and the plate material 30 arranged on the slope S, and is formed in a cylindrical shape (cylindrical shape in this embodiment) surrounding the outer circumference of the anchor 14 . In this embodiment, part of the spacer 40 is embedded in the ground.

The spacer 40 of the present embodiment includes a tubular body portion 42, a flange portion 44 protruding radially outward from the outer peripheral surface of the body portion 42, and one end portion of the body portion 42 (hereinafter referred to as an upper end portion 42a). ) and grooves 46 formed therein. The spacer 40 can be made of a resin material such as polyvinyl chloride (PVC) or polyethylene (PE), or a metal material. The height of the spacer 40 (that is, the length of the main body portion 42 in the cylinder axis direction) can be, for example, 15 mm to 50 mm. The outer diameter of the body portion 42 is smaller than the diameter of the through hole of the underlay material 16 and larger than the through hole 34 of the plate member 3 to be described later. It is formed larger than the diameter of the through hole. The depth and width of the grooves 46 are formed to be large enough to fit the wire members 24 forming the net body 20 in the grooves 46 .

When the spacer 40 is installed, the anchor 14 passes through the body portion 42 , and the end portion of the body portion 42 that does not have the groove portion 46 (hereinafter referred to as the lower end portion 42 b ) corresponds to the through hole of the underlay material 16 . and embedded in the ground, and arranged so that the upper end portion 42a side of the body portion 42 protrudes from the slope S together with the flange portion 44 . Further, in this embodiment, the spacer 40 is filled with a grouting material 18 such as cement milk or mortar.

In addition, the spacer 40 may be arranged between the slope S and the plate member 30 so that the height of the net body 20 from the slope S can be adjusted. As shown in (B), a configuration in which the underlying material 16 is not provided may be employed. In such a case, it is preferable that one end of the spacer 40 is buried in the ground. As another form, as shown in FIG. 6(C), it has a cylindrical shape that does not have the groove portion 46 or the flange portion 44, and the outer diameter of the main body portion 42 is larger than the through hole of the underlay material 16. , and may be sandwiched between the underlay material 16 and the plate material 30 . In each form, the length of the spacer 40 in the cylinder axis direction can be appropriately set in consideration of the length of the portion protruding from the slope S and the length of the portion buried in the ground. 40 has a protective coating for abrasion resistance to prevent abrasion of the surface of the net body 20 at least at a portion that can contact the net body 20 in the installed state (for example, the upper end 42a side of the main body part 42). You may have This protective film can be made of, for example, a rubber material or a resin material.

As shown in FIGS. 7A to 7C, the plate material 30 is a plate material having a through hole 34 formed in the center through which the anchor 14 is inserted. It can be formed by a plate or the like. The plate material 30 is formed such that the length of the major axis (the length in the long direction) is larger than the meshes 22 of the mesh body 20 in plan view. The plate material 30 can adopt various shapes such as a circular shape, an elliptical shape, and a polygonal shape in plan view, and is formed in a substantially hexagonal shape in this embodiment.

It is preferable that one or more protrusions 36 protruding from the lower surface 32 be formed on the lower surface 32 (that is, the surface facing the slope S) of the plate member 30 . In this embodiment, six protrusions 36 are formed on the lower surface 32 . The length of the projecting portion 36 is equal to or greater than the thickness d of the mesh 20 .

Between the plate material 30 and the mesh body 20, a buffer 35 is arranged for wear resistance. In the present embodiment, the cushioning body 35 is a film integrally formed on the surface of the plate member 30, as indicated by dots in FIG. The damping body 35 can be made of, for example, a rubber material or a resin material. In this embodiment, the coating, which is the buffer 35, is formed on the side surface 33 of the plate material 30 and the lower surface 32 of the plate material 30 including the protrusions 36, but is not limited thereto. may be formed in A sheet-like cushioning body 35 separate from the plate material 30 may be arranged between the mesh body 20 and the plate material 30. In such a case, the cushioning body 35 preferably has flexibility.

As shown in FIGS. 2 and 8, the plate material 30 is placed on the mesh body 20 with the anchors 14 passed through the through holes 34 so that the projections 36 penetrate the meshes 22 of the mesh body 20 . placed in The plate member 30 is fixed to the head of the anchor 14 by a cap nut 50 fastened to the top of the anchor 14 in a state in which movement toward the slope S is suppressed by the spacer 40 . By inserting the protrusions 36 into the meshes 22 in this way, when an external force is applied to the mesh 20 and the relative positions of the plate material 30 and the mesh 20 are about to shift, the projections 36 can be displaced. The locking structure between the portion 36 and the linear members 24 can prevent the mesh body 20 from being dislocated.

Next, a method for constructing the slope protection structure 10 described above will be described.

First, as shown in FIG. 9, on the slope S on which the slope 12 is installed, the anchors 14 are driven into the areas where the slope 12 is not arranged (anchor driving step). In this embodiment, a plurality of anchors 14 are placed at intervals on the slope S so that one anchor 14 exists in each rectangular frame of the grid-like lawn frame 12 .

The installation of the anchor 14 is performed in the following procedure. First, a drilling machine (not shown) is used to drill the slope S to a predetermined depth, and then a grout material injection hose (not shown) is inserted to the bottom of the drilled hole 19 to remove cement milk, mortar, or the like. A grout material 18 is injected into the drilled hole 19 from the bottom of the hole. After the grout material 18 is filled up to the vicinity of the slope S, the underlay material 16 and the spacer 40 are arranged on the slope S. At this time, the underlying material 16 and the spacer 40 are arranged so that the drilled hole 19 communicates with the through hole of the underlying material 16 and the hollow interior of the spacer 40 . After that, the spacer 40 is filled with the grout material 18 of the same material as the grout material 18 in the bored hole 19 . After the grout material is injected, the anchor 14 is inserted into the hole so as to penetrate the spacer 40 and the underlay material 16, and the grout material 18 is cured. As a result, the grout material 18 in the spacer 40 and the grout material 18 around the anchor 14 on the underground side are integrated.

As for the procedure for placing the anchor 14, the grout material 18 may be injected after inserting the anchor 14 into the drilled hole 19 after drilling. In such a case, after the grout material 18 is filled up to the vicinity of the slope S, the underlay material 16 and the spacer 40 are arranged at predetermined positions from the head side of the anchor 14, and the grout material 18 is injected into the arranged spacer 40. can.

After setting the anchors 14, as shown in FIG. 10, the net body 20 is laid on the slope S from above the law frame 12 (net body laying step). The net body 20 of the present embodiment is formed in a size capable of covering the entire area of the slope S where the slope frame 12 is arranged.

Next, as shown in FIGS. 2 and 4, the plate material 30 is attached to the head of the anchor 14 from above the net body 20, and the plate material 30 moves the net body 20 to the height of the top surface 12c of the slope frame 12. lower than the height (plate material installation process). The plate member 30 is fixed by fastening the cap nut 25 to the head of the anchor 14 while the head of the anchor 14 is inserted through the through hole 34 . With the plate material 30 fixed to the anchor 14 , the protrusions 36 of the plate material 30 are inserted through the meshes 22 of the mesh body 20 . At least a part of the protrusions 36 is preferably positioned at the bent portion of the linear member 24 (that is, the corner portion of the rhombic mesh 22), as shown in FIG. When the wire 24 is in contact with the spacer 40 and the upper end 42 a while the mesh 20 is pushed down, the wire 24 is inserted into the groove 46 of the spacer 40 .

In this way, by fixing the net body 20 covering the slope S from above the law frame 12 to the slope S using the anchors 14, the underlay material 16, the spacers 40, the plate members 30 and the cap nuts 50, the protective structure 10 is It is formed.

In the slope protection structure 10 described above, the slope protection performance of the slope frame 12 can be enhanced by pressing the slope frame 12 against the slope S by the net body 20 . Furthermore, even in the area within each frame where the slope frame 12 is not arranged, the anchor 14 is driven up to the stable stratum G1 and is pressed from above by the net body 20, thereby preventing slope failure. In particular, in the present embodiment, the net body 20 is composed of the wire rods 24 manufactured from hard steel wire rods having a tensile strength of 800 to 2000 N/mm ² . It can exhibit high tensile strength and springiness. As a result, it is possible not only to prevent the slope surface from collapsing, but also to prevent surface slippage at a depth of 1 m to 3 m from the slope surface.

In addition, in the protective structure 10, since a zinc plating layer or a zinc aluminum alloy plating layer having an adhesion amount of 80 g/m ² or more is formed on the surface of the net body 20 used in the protective structure 10, the net body 20 and the law frame 12, the anti-corrosion performance of the mesh body 20 can be maintained and the structure with excellent durability can be obtained.

Furthermore, in this embodiment, by providing the buffer 35 on the surface of the plate material 30, it is possible to prevent the mesh 20 and the plate material 30 from rubbing against each other and to prevent the surface of the mesh 20 from being worn. As a result, the anti-corrosion performance of the net body 20 can be improved. In addition, by inserting the wire members 24 that constitute the mesh body 20 into the grooves 46 of the spacer 40, the mesh body 20 is prevented from rubbing against the spacer 40 and worn, thereby improving the anti-corrosion performance of the mesh body 20. can be higher. Although not shown, if a protective film is provided on the surface of the spacer 40, the wear suppressing effect can be further enhanced.

In addition, in the present embodiment, the head of the anchor 14 protruding from the slope S is covered with the cap nut 40 and also covered with the grout material 18 filled in the spacer 40, thereby reducing the exposed area of the anchor 14. It is possible to reduce and prevent the generation of rust, thereby enhancing the anti-corrosion properties of the anchor 14 .

FIG. 11 shows a modification of the protective structure 10. FIG. In the example shown in FIG. 11, a cushioning material 28 for abrasion resistance is arranged between the lawn frame 12 and the net body 20 . The cushioning material 28 can be made of, for example, a resin material, a rubber material, or the like and has a thickness of 2 to 3 mm. placed. By arranging the cushion material 28 in this way, it is possible to prevent wear of the mesh body 20 and further improve anti-corrosion properties.

Next, another embodiment of the protective structure 10 will be described with reference to FIG. As shown in FIG. 12(A), in the protective structure 10 of the present embodiment, a greening base material 60 on which plants housed inside a bag 62 can grow is further provided between the slope S and the net body 20. are placed. As the greening base material 60, for example, a material (vegetation base material) mixed with plant seeds or the like can be used, which is obtained by cutting grass, felled wood, or thinned wood.

FIG. 12(B) is a plan view of the bag 62 into which the greening base material 60 is injected. The bag body 62 has a bag portion 64 made of cloth woven with biodegradable threads and an injection portion 68 for injecting the greening base material 60 into the bag portion 64 . The bag portion 64 has air and water permeability. At least one bag body 62 is preferably arranged in each rectangular frame so as to cover substantially the entire area in each rectangular frame of the law frame 12 . The bag body 62 of this embodiment has a hole 66 in the central portion of the bag portion 64 through which the anchor 14 can pass. The bag 62 may have a rectangular shape without the holes 66 instead of the illustrated example. A plurality (eg, 2 to 4) may be arranged around the anchor 14 so as to fill the interior.

In the protective structure 10 of this embodiment, the greening base material 60 is installed in the following procedure. After the anchor setting process, a bag body 62 is arranged in each frame of the law frame 12 . At this time, the greening base material 60 is not injected into the bag body 62 . Next, the net body 20 is laid from above the slope frame 12 and the bag body 62 (net body laying step), after that, the plate material 30 is attached to the head of the anchor 14, and the net body 20 is pushed down to the slope S side ( plate material installation process). After the plate material 30 is attached, the fluid greening base material 60 is injected into the bag 62 from the injection part 68 of the bag 62 (greening base material injection step). The injection part 68 may be removed from the bag part 64 after the greening base material 60 is injected. Moisture in the greening base material 60 evaporates over time and changes from a liquid state to a solid state.

Thus, by installing the greening base material 60 between the slope S and the mesh 20, the area where the slope 12 is not installed can be greened, and as a result, the surface of the slope exposed to the wind and rain can be greened. It is possible to suppress the outflow of earth and sand. In addition, before the step of installing the plate material, the bag 62 is arranged on the slope S, the plate material 30 is arranged on the bag 62, and then the greening base material 60 is injected, so that the plate material 30 and the slope S The greening base material 60 can be appropriately filled also in the area between . In the example shown in FIG. 12, instead of the greening base material 60, a grout material such as mortar or soil may be injected into the inside of the bag body 62. As shown in FIG.

FIG. 13 shows another embodiment of a slope protection structure 10 with a greening substrate 60 . In this embodiment, after fixing the net body 20 to the slope S (after the step of installing the plate material), the base material sprayer 70 is used to spray the greening base material 60 onto the slope S from above the net body 20 through the mesh 22 . , the greening base material 60 is injected between the slope S and the mesh body 20 (greening base material injection step). The greening base material 60 is sprayed on the area of the slope S where the law frame 12 is not arranged. Thus, the greening base material 60 may be placed on the slope S by spray pouring.

Next, still another embodiment of the slope protection structure 10 will be described with reference to FIG. 14 . In addition, in this embodiment, the structure of the law frame 12 is different from the previous embodiment shown in FIGS. are the same, detailed description of these same structures will be omitted.

In this embodiment, the law frame 12 installed on the slope S is composed of a plurality of cross-shaped blocks 11 spaced apart from each other. The block 11 is formed, for example, by pouring concrete into cross-shaped reinforcing bars. In each block 11, an anchor 13 extending to the stable stratum G1 is driven in the central portion of the cross. Thus, the lawn frame 12 may be composed of a plurality of separated blocks 11 . Further, the shape of the block 11 is not limited to a cross shape in plan view as in the illustrated example, and various shapes such as a rhombus shape in plan view can be adopted.

In the protective structure 10 of this embodiment, the anchors 14 for fixing the net body 20 are driven into the slope S of the non-arranged area of the blocks 11, and then the net body is mounted on the slope frame 12 composed of a plurality of blocks 11. 20 is laid. After that, the mesh 20 is pushed down to a position lower than the top surface of the block 11 by the plate member 30 fixed to the head of the anchor 14 . In addition, in the protective structure 10 of the present embodiment, a greening base material 60 may be further provided between the slope S and the net body 20 .

It should be noted that the present invention is not limited to the above-described embodiments and modifications, and various modifications are possible without departing from the scope of the invention.

10 Slope protection structure 11, 12 Slope 12a Vertical frame member 12b Horizontal frame member 14 Anchor 16 Underlay material 18 Grout material 20 Net body 30 Plate material 40 Spacer 50 Cap nut 60 Greening base material 62 Bag G1 Stabilizing layer G2 unstable strata

Claims (6)

In the protective structure of the slope where the law frame for slope stabilization is installed,
a plurality of anchors placed at intervals in a non-existing area of the law frame within the setting range of the law frame;
A plate-shaped underlay material arranged on the slope and through which the anchor penetrates;
a net body composed of a rhombic wire net laid on the slope from above the law frame;
a plate member that is attached to the head of the anchor and applies tension to the net body by pushing down the net body to a position lower than the height position of the top surface of the law frame;
a cylindrical spacer disposed between the underlay material and the plate material and surrounding the outer circumference of the anchor ;
The wire material constituting the net body is a wire material made from a hard steel wire material, and has a zinc plating layer or a zinc aluminum alloy plating layer with an adhesion amount of 80 g / m ² or more on the surface,
The spacer has a tubular main body and a flange protruding radially outward from an outer peripheral surface of an axially intermediate portion of the main body,
the flange portion abuts on the upper surface of the underlaying material, the lower end portion of the main body portion penetrates the underlaying material and extends toward the ground;
A slope protection structure , wherein an interior of the main body is filled with a grout material . 2. The slope protection structure according to claim 1, wherein the upper end portion of the spacer is formed with a groove into which the linear member forming the net can be fitted. 3. The slope protection structure according to claim 1, wherein a buffer for wear resistance is provided between said plate member and said net. 4. The wire-shaped material constituting the net has a diameter of 2 to 5 mm and a tensile strength of 800 to 2000 N/mm ² . slope protection structure. In a slope protection method in which a slope stabilization frame is installed,
an anchor placing step of placing a plurality of anchors at intervals in a non-existing region of the law frame within the installation range of the law frame;
A net body laying step of laying a net made of a rhombic wire net on the slope from above the law frame;
A plate material installation step of fixing the plate material to the anchor in a state where the net body is pushed down to a position lower than the top surface height position of the law frame by a plate material having a larger diameter than the mesh of the net body. , including
The wire material constituting the net body is a wire material made from a hard steel wire material, and has a zinc plating layer or a zinc aluminum alloy plating layer with an adhesion amount of 80 g / m ² or more on the surface,
In the anchor setting step, a plate-shaped underlay material through which the anchor penetrates is arranged on the slope, and a cylindrical underlay material is arranged between the underlay material and the plate material and surrounds the outer circumference of the anchor. Place a spacer,
The spacer has a tubular main body and a flange provided in an axially intermediate portion of the main body and protruding radially outward from the outer peripheral surface of the main body,
the flange portion abuts on the upper surface of the underlaying material, the lower end portion of the main body portion penetrates the underlaying material and extends toward the ground;
A method for protecting a slope, characterized by filling the inside of the main body with a grout material after disposing the spacer . 6. The slope protection method according to claim 5, further comprising a greening base material injection step of injecting a greening base material between the slope and the net body after the plate material installation step.

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