JP2016056506A - Wire net for slope protection and slope protection method using the wire net for slope protection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an environment-friendly wire net for slope protection that protects a slope and vegetation thereon more readily, along with a slope protection method using the wire net for slope protection.SOLUTION: A slope protection method uses a wire net 10 for slope protection that includes a hard steel wire as a constituent wire material 13, a wire net body 12 covering a slope surface to be protected, and a fiber layer 16 being engaged with the constituent wire material 13 of the wire net body 12 and having a mesh smaller than a mesh of the wire net body 12. The configuration allows the wire net body 12 to firmly cover the slope surface and inhibit erosion thereof, the wire net body being higher in spring property, more difficult to get deformed, and higher in strength compared to a conventional wire net made of iron wires. Also prevented is a surface layer landslide at a depth between 1 m and 3 m from the slope surface, in addition to the slope surface part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a slope protection wire mesh used for slope protection and a slope protection method using the slope protection wire mesh.

  There are various techniques for protecting the slope depending on the scale of the slope and the internal conditions. For example, there is a resin net called a vegetation sheet or a vegetation mat in which seeds are mounted. By extending these on the slope (so-called sheet construction method), the plants are entangled with the net and are also extended into the soil on the surface of the slope to grow, thereby ensuring vegetation.

  Further, as in Patent Document 1, there is also a vegetation net that has a synthetic resin wire entangled with a general-purpose wire mesh such as a rhombus wire mesh. Vegetation is applied to the slope by spraying a mixed material composed of seeds, soil and fertilizer in a state where the net for vegetation is spread on the slope. Thereby, the mixed material which consists of a seed, soil, and a fertilizer can be hold | maintained on the slope with a comparative gradient by the line made from a synthetic resin entangled with the general purpose wire mesh.

  In addition, laying a wire mesh or resin net on the slope, spraying vegetation bases such as seeds and soil, to prevent the collapse of the surface of the natural ground and the erosion of the sprayed vegetation base, from above There is also a technique for forming a concrete frame structure.

  Patent Document 2 discloses a technique in which the above-described frame structure is improved. FIG. 11 (corresponding to FIG. 1 of Patent Document 2) shows the frame structure, and this frame structure is made of synthetic resin as shown in FIG. 10 (corresponding to FIG. 3 of Patent Document 2). A vegetation constructed by installing a formwork 110 formed by combining the strip-shaped nets 100 made in a grid pattern on the slope B0 and spraying a sand base material mixed with sand, fibers, cement and water on the formwork 110. This is a frame body structure 120 (see FIG. 11).

  In addition, when the slope of the slope becomes steep, the amount of precipitation per slope area decreases and water easily flows, making it difficult to store water on the slope. In relation to this, it has been reported that the slope of the slope and the vegetation on the slope generally become shorter and the root system becomes shorter and the root layer becomes thinner. Therefore, when vegetation is applied to a slope with a steep slope, it is necessary to thicken the growth base.

Japanese Utility Model Publication No. 60-14136 Japanese Patent No. 4145340

  However, according to the sheet method that attaches seeds to a resin net called a vegetation sheet or vegetation mat, it is possible to vegetate the ground surface, but depending on the condition of the slope, it is attached to the resin net. It is impossible to prevent erosion of vegetation base materials such as seeds.

  Further, according to the vegetation net of Patent Document 1, the synthetic resin filaments entangled with the general-purpose wire mesh holds the mixed material composed of seeds, soil and fertilizer sprayed even on a relatively sloping slope. Can prevent its erosion.

  However, in order to ensure sufficient plant growth on a slope with a relatively slope, it is necessary to thicken the growth base as described above. When a thick mixed material layer is formed on the slope, a general-purpose wire mesh made of iron wire is used. Has low strength and easily plastically deforms. That is, a so-called sag occurs in which the wire mesh is plastically deformed by the weight of the sprayed mixed material, and this sag causes cracks at a plurality of locations in the mixed material layer. This crack causes further erosion of the mixed material layer. Therefore, depending on the vegetation net having a general-purpose wire mesh made of a conventional iron wire, it is difficult to maintain a growth base composed of a thick mixed material layer.

  Furthermore, depending on the general-purpose wire mesh made of iron wire, if the surface portion of the slope is unstable, it cannot be dealt with, and the surface portion of the slope slides down, and the sprayed mixed material also flows out.

  In addition, according to the slope protection technology for providing a frame structure such as a legal frame on the slope, it is possible to prevent the slope surface portion from being collapsed by the frame structure and to prevent the vegetation base material that has been blown onto the slope from flowing out. . However, the work of forming a frame structure over a wide range on a slope having a gradient takes time and effort and is complicated. Moreover, it is not preferable from the viewpoint of the environment to form a frame structure such as a legal frame constructed of concrete on the slope. In this regard, it has been proposed to change the frame structure to the vegetation frame structure of Patent Document 2 to be good for the environment, but there is no problem with the complexity of providing the frame structure. It has not been.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to provide a slope protection wire mesh capable of protecting the slope surface and ensuring vegetation more easily in the environment and a slope using the slope protection wire mesh. Provide protection methods.

The wire mesh for slope protection according to claim 1 for solving the above object,
A wire made of hard steel is used as a constituent wire, and includes a main body wire mesh that covers the surface of the slope to be protected, and a fiber layer that engages with the constituent wire material of the main body wire mesh and has an eye smaller than the mesh of the main body wire mesh. It is characterized by that.

  According to this structure, since the main body metal mesh uses the wire made of hard steel as the constituent wire rod, the spring property is higher, the plastic deformation is difficult, and the strength is higher than that of the general-purpose metal mesh made of iron wire. Therefore, the main body metal mesh can cover the slope surface portion firmly and prevent the slope surface portion from being eroded. Further, the erosion of the slope surface portion can be further suppressed by the fiber layer that engages with the constituent wire rod of the main body metal mesh and has an eye smaller than the mesh of the main body metal mesh.

  When the vegetation base material is sprayed from above the main body metal mesh, the vegetation base material penetrates not only into the main body metal mesh but also into the fiber layer having an eye smaller than that of the main body metal mesh. Maintenance of the sprayed vegetation base material is ensured, and the outflow of the vegetation base material can be prevented.

  Furthermore, because the main body wire mesh is made of hard steel wire, even if the vegetation base material is sprayed thickly, the main body wire mesh is not deformed (so-called sagging) due to its weight, and is thicker. Generation | occurrence | production of the crack to the sprayed vegetation base material surface and the erosion of the vegetation base material layer resulting from this crack can also be prevented.

  Thus, since the weathered slope surface portion is maintained and the vegetation base material is stably held, it is freed from the trouble of separately providing a concrete frame structure, and a concrete frame structure. It is good for the environment.

  The invention according to claim 2 is the slope protecting wire mesh according to claim 1, wherein the fiber layer is mainly engaged with the body wire mesh on the slope side in the slope installation state of the body wire mesh. The fibers constituting the fiber layer are entangled with the constituent wire rods of the main body metal mesh so as to exist.

  According to this configuration, the fiber layer is mainly present on the slope side, that is, the main part of the fiber layer is pressed against the slope side by the main body metal net, so when the vegetation base material is blown, The vegetation base material can be more stably held by the fiber layer fixed to the slope side by the wire mesh. Further, since the fiber layer is located at the lower part of the main body metal mesh, the fiber rises from the lower side to the upper side, and has a rising portion entangled with the constituent wire material of the main body metal mesh. The sprayed vegetation base material is supported by the rising portion and is held more stably.

  Furthermore, it is not necessary to use a separate member when integrating the fiber layer and the main body metal mesh, and the structure is further simplified.

The invention according to claim 3 is the slope protecting wire mesh according to claim 1 or 2, wherein the constituent wire has a tensile strength of 800 to 2000 N / mm ² .

According to this configuration, a commercially available mild steel wire, i.e., iron wire (typically, tensile strength 290~540N is / mm ²⁾ Unlike a general-purpose wire mesh-based, manufactured by hard steel having a tensile strength of 800~2000N / mm ² The main body wire mesh is composed of the wire. Therefore, when the slope protection wire mesh is fixed to the slope by the pins, it is possible to obtain the effect of protecting the weathered surface portion of the slope and ensuring the vegetation of the entire slope, more easily and environmentally. Further, when combined with an anchor such as a rock bolt, it is possible to prevent surface slippage from a slope surface to a depth of 1 m to 3 m as well as the slope surface portion.

  According to a fourth aspect of the present invention, in the slope protection wire mesh according to any one of the first to third aspects, at least the surface of the fiber layer in the slope installed state on the main body wire mesh side is an uneven surface in which the raised portion and the recessed portion are continuous. It is characterized by becoming.

  When a vegetation base material is sprayed on the slope, the roots of the plant mainly extend radially about the vertically downward axis. Therefore, of the radially extending roots, the roots extending in the direction away from the slope are exposed to the outside, and the stability of the plant becomes worse. The steep slope slope increases the number of roots exposed to the outside. To do. It is in accordance with the laws of nature that the roots of plants mainly extend vertically downward, so the proportion of roots exposed to the outside cannot be reduced no matter how thick the vegetation substrate is sprayed.

  According to this configuration, there is a continuous unevenness on the surface of the main body mesh of the fiber layer with the slope protection wire mesh installed on the slope. A fiber layer surface having an inclination angle different from the angle is formed. That is, when the vegetation base material is sprayed, the sprayed vegetation base material layer forms a terraced surface that is gentler than the slope of the natural mountain slope and close to the horizontal on the surface of the fiber layer on the main body metal mesh side. . Since the surface of the terraced vegetation base layer that is almost horizontal has a gentle slope, the exposure rate of the roots of the plant can be reduced, and further stabilization of the vegetation can be achieved.

  According to a fifth aspect of the present invention, in the slope protection method using the slope protection wire mesh according to any one of claims 1 to 4, the slope protection wire mesh is inclined on the side where the fiber layer mainly exists. A wire mesh extending step for extending the entire slope to be protected, a wire mesh fixing step for fixing the spread slope protecting wire mesh at a plurality of locations on the slope, And a seed spraying step of spraying a vegetation base material containing at least plant seeds from above the fixed slope protecting wire mesh, wherein no frame structure is provided on the slope protecting wire mesh.

  According to this configuration, the slope protection wire mesh is spread over the entire slope to be protected, the wire mesh is fixed to the slope at a plurality of locations, and the vegetation base material containing plant seeds is sprayed on the wire mesh, By a simpler process than the conventional method in which no structure is provided, the slope surface portion is securely protected and the sprayed vegetation base material can be prevented from flowing out. Furthermore, since the frame structure is not provided, the slope protecting method is better for the environment than before.

  According to a sixth aspect of the present invention, in the slope protecting method according to the fifth aspect, in the wire mesh fixing step, a pin having an engaging portion engageable with the main body metal mesh is disposed on the head, and the main body metal mesh is disposed on the head. It is performed by driving into the slope in an engaged state.

  According to this configuration, the wire mesh fixing process is a simple process in which the pin with the main body metal mesh engaged with the head is driven into the slope, so that it is possible to more easily protect the slope surface portion and ensure vegetation. Is possible.

  The invention according to claim 7 is the slope protecting method according to claim 5, wherein the wire mesh fixing step includes the upper end of the anchor placed on the slope in a state where the upper end protrudes from the slope at the scattered point. The pressure receiving plate capable of interspersedly pressing a predetermined range of the main body metal mesh is fixed in a state where the main body metal mesh is pressed in the inclined direction.

  According to this configuration, since the main body metal mesh is pressed in the inclined direction by the pressure receiving plate fixed to the upper end of the anchor, not only can the protection of the inclined surface part and the securing of the vegetation base material be obtained, but also deeper than the inclined surface part. Surface slip to a depth of 1 to 3 m can also be prevented.

  The invention according to claim 8 is the slope protecting method according to claim 7, wherein the pressure receiving plate has one or a plurality of protrusions protruding from one surface, and the wire mesh fixing step includes the pressure receiving plate. The projection of the mesh is inserted into a mesh different from the mesh through which the anchor is inserted so that the side of the projection is close to both the uppermost slope and the lowermost slope of the other mesh, The pressure receiving plate is fixed by fixing the main body metal mesh in a state in which the main body metal mesh is pressed in the slope direction.

  In the region below the pressure receiving plate in the slope protection wire mesh extended on the slope, a strong tensile force acts above and below the slope direction of the slope. Therefore, when the slope protection wire mesh is pulled upward in the inclination direction in the surface spreading direction of the wire mesh, stress on the anchor concentrates at the corner (intersection) of the lowest slope of the mesh through which the anchor is inserted. In addition, when the slope protection wire mesh is pulled downward in the inclination direction in the surface spreading direction of the wire mesh, stress on the anchor concentrates at the corner (intersection) of the uppermost slope of the mesh through which the anchor is inserted.

  According to this configuration, with the pressure receiving plate fixed to the upper end of the anchor, the protrusion is inserted into a mesh different from the mesh through which the anchor in the slope protection wire mesh extended on the slope is inserted, And the side part of a projection part is adjoining at least both the slope uppermost part and the slope lowest part of the mesh. Therefore, when the slope protection wire mesh is pulled downward in the slope inclination direction, the side portions of the protrusions and the anchors that are close to the top of the slope of the mesh that is inserted immediately contact the corners (intersections) of the mesh. When the slope protection wire mesh is pulled upward in the slope inclination direction, the side portions of the protrusions and the anchors that are close to the bottom of the slope of the mesh that is inserted immediately contact each corner (intersection) of the mesh, The stress acting on the slope protection wire mesh is reliably dispersed.

  Thereby, the breakage / damage of the slope protection wire mesh at the mesh portion where the anchor abuts is suppressed, and the slope protection wire mesh can exhibit a greater earth pressure receiving force. That is, by combining with the pressure receiving plate having the protrusions, the ability to protect the slope surface by the slope protection wire mesh can be improved without changing the wire mesh itself.

  According to the present invention, it is possible to more easily protect the slope surface and secure vegetation without providing a frame structure on the slope. Therefore, it is possible to shorten the construction period of the slope protection work accompanied by the greening of the slope, and it is an economical and environmentally friendly slope protection work.

(A) It is a top view of the wire mesh for slope protection which concerns on embodiment of this invention, and (B) IB-IB sectional view taken on the line. (A) It is a top view of the structural wire which comprises the main body metal mesh which concerns on this Embodiment, (B) It is a perspective view, (C) It is a bottom view. It is sectional drawing of the slope for demonstrating the process of the slope protection method using the wire mesh for slope protection which concerns on this Embodiment. It is the A section enlarged view of Drawing 3 (C). It is the figure which expanded further and showed typically the A section of FIG.3 (C) for demonstrating the cross-sectional shape of the fiber layer 16. FIG. It is a perspective view of the pressure receiving plate used in the modification of the wire-mesh fixing process of the slope protection method. It is sectional drawing of the slope for demonstrating the modification of the wire-mesh fixing process of the slope protection method. It is the VIII-VIII sectional view taken on the line of FIG. It is a figure corresponding to the VIII-VIII line sectional view of Drawing 7 for explaining other modes of the projection part concerning a modification. It is a perspective view for demonstrating the formwork used for the conventional improved frame structure. It is a perspective view for demonstrating the conventional improved frame structure. It is sectional drawing of the slope which shows the growth state of the plant body in the vegetation base material sprayed on the steep slope.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. A slope protection wire mesh used for slope protection and a slope protection method using the slope protection wire mesh will be described with reference to FIGS. FIG. 1 is an explanatory view of a slope protecting wire mesh according to the present embodiment, FIG. 2 is an explanatory view of constituent wires constituting the main body wire mesh, and FIG. 3 is a view for explaining steps of a slope protecting method using the slope protecting wire mesh. 4 is an enlarged view of a portion A of FIG. 3C, and FIG. 5 is an enlarged view of a portion A of FIG. 3C for explaining the sectional shape of the fiber layer 16. FIG.

  As shown in FIG. 1, the slope protecting wire mesh 10 is engaged with a body wire mesh 12 that covers the slope B1 to be protected (see FIG. 3) and a constituent wire 13 of the body wire mesh 12, and from the mesh of the body wire mesh 12. And a fiber layer 16 having small eyes.

  The main body metal mesh 12 is composed of a constituent wire 13 made of hard steel, and specifically preferred is a wire made from a hard steel wire defined in JIS G 3506, for example, a hard steel wire (JIS G 3521), galvanized steel wire (JIS G 3548), and the like.

A hard steel wire is a commercially available mild steel wire that is a constituent wire of a conventional general-purpose wire mesh, that is, has a spring property as compared with an iron wire, is hard to be plastically deformed, and is an iron wire (tensile strength 290 N / mm ^{2 to} 540 N). / Mm ² ), the tensile strength is high.

  Therefore, the main body metal mesh 12 which uses the wire made of hard steel as the constituent wire rod 13 has an effect superior to that of the conventional general-purpose metal mesh as will be described later.

Strand tensile strength of construction wire 13 is in the range of 800N ^/ mm ² ~2,000N ^/ mm 2 as a guide, preferably in ^the range of ^{1,000N / mm 2 ~2,000N / mm 2} . The diameter φ of the constituent wire 13 is in the range of 2.0 mm to 4.0 mm, and preferably 2.5 mm or more.

  The constituent wire 13 is preferably subjected to anticorrosion treatment, and as an advantageous anticorrosion treatment, a surface of a hard steel wire is first subjected to Zn / Al plating, and a coating of saturated polyester (PET) is provided thereon. Is mentioned. However, other anticorrosion treatments are also applicable.

  As shown in FIG. 2A, the constituent wire 13 is formed in an acute zigzag shape in a plan view, and in a spiral shape in the extending direction as shown in FIG. That is, the substantially straight straight line portion 13a and the straight line portion 13b are formed in the above-described spiral shape by the bent portion 13c therebetween.

  The acute angle formed by the straight line portion 13a and the straight line portion 13b is preferably 30 to 50 ° in plan view as shown in FIG. Further, as shown in FIG. 2C, the height interval I between the straight line portion 13a and the straight line portion 13b is preferably three times or more than the thickness of the constituent wire 13.

  The component wire 13 bent as described above is connected at the bent portion 13c of each component wire 13, and, as shown in FIG. 1, a rhombus wire mesh (having a rhombus mesh composed of sides 12a, 12b, 12c and 12d) It becomes the main body wire mesh 12). The rhombus mesh size is such that the length of the longer diagonal is in the range of 40 mm to 150 mm, and the length of the shorter diagonal is in the range of 40 mm to 80 mm.

  The fiber layer 16 has a three-dimensional network structure formed by intertwining or adhering the fibers 16a. The fiber layer 16 having this three-dimensional network structure has eyes smaller than the mesh of the main body metal mesh 12. As will be described later, the size of the mesh of the fiber layer 16 is such that the vegetation substrate 22 including the sprayed seeds 20 is also transmitted to the lower part of the fiber layer 16 in a state where the slope protection wire mesh 10 is installed on the slope B1. The size is such that the roots of the plants that have been germinated and grown from the seed 20 can be intertwined. Preferably, the mesh size of the fiber layer 16 is about 1/3 of the mesh size of the main body metal mesh 12, and particularly preferably, the distance between the fibers 16a constituting the mesh is in the range of about 10 mm to 30 mm. . In addition, the size of the eyes of the fiber layer 16 can be appropriately changed depending on the properties of the vegetation base material 22.

  The fibers 16a constituting the fiber layer 16 may be natural fibers such as palm fibers and hemp fibers, or may be synthetic resin fibers such as spun polyester fibers and aramid fibers. In the present embodiment, a fiber formed by fusing polyethylene fibers (that is, fibers 16a) immediately after spinning to a diameter of about 0.5 mm to 2.0 mm to the previously spun polyethylene fibers. Layer 16 is used.

  As shown in FIG. 5 for explaining the cross-sectional shape of the fiber layer 16, on one surface 16b of the fiber layer 16, a hemispherical bulge 17a and a hemispherical depression 17b are continuously arranged in a lattice shape. It is an uneven surface. In the other surface 16c of the fiber layer 16, a portion facing the raised portion 17a of the one surface 16b is a recessed portion 17b, and a portion facing the recessed portion 17b of the one surface 16b is a raised portion 17a. That is, the fiber layer 16 has a corrugated layer shape generated by the continuation of the raised portion 17a and the recessed portion 17b in a sectional view (see FIG. 5). The size of the raised portion 17a and the recessed portion 17b is, for example, in the range of about 20 mm to 30 mm in diameter in plan view, and the height of the raised portion 17a and the recessed portion 17b is, for example, about 10 mm in the sectional view shown in FIG. It is in the range of ˜20 mm. The fiber layer 16 has many void portions (eyes) inside. The thickness of the fiber layer 16 is, for example, about 5 mm to 30 mm.

  The surface 16b (see FIG. 5) of the fiber layer 16 having such a shape is brought into contact with one surface of the main body metal mesh 12, and in this state, the diameter is within the range of φ0.5 mm to 2.0 mm from the other surface. The polyethylene layer (that is, the fiber 16a) immediately after spinning is fused to the fiber layer 16 through the constituent wire 13 of the main body mesh 12, so that the fiber layer 16 and the main body metal mesh 12 are integrated, and the slope protecting wire mesh 10 (see FIG. 1) is formed.

  That is, the fiber layer 16 is engaged with the main body metal mesh 12 so that the fiber layer 16 mainly exists on the inclined surface side when the main body metal mesh 12 is installed on the inclined surface B1. According to the present embodiment, it is not necessary to use a separate member when the fiber layer 16 and the main body metal mesh 12 are integrated, so the configuration of the slope protecting wire mesh 10 is simplified.

  The slope protecting wire mesh 10 formed in this way is fixed to the slope B1 by anchor pins 21 (pins). As shown in FIG. 3B, the anchor pin 21 is a substantially J-shaped reinforcing bar having a diameter of about 16 mm and a length of about 40 cm. The head 21 a of the anchor pin 21 is bent or curved in a hook shape, and is an engaging portion that can engage with the main body metal mesh 12. The slope B1 into which the anchor pin 21 is driven is a slope composed of a stable formation such as a bedrock and a surface portion having a thickness of 5 cm to 10 cm made of weathered debris on the stable formation. The debris on the slope surface portion easily rolls and moves on the slope B1 due to, for example, wind and rain.

  Next, the vegetation base material 22 including the seed 20 that is sprayed onto the slope protection wire mesh 10 fixed to the slope B1 will be described. As the seed 20, a foreign or conventional herbaceous seed is used. Examples of the vegetation base material 22 include bark compost (humus soil), fertilizer, and wood fiber (fiber). The property of the vegetation base material 22 can be changed by appropriately adding water.

  Next, a slope protection method using the slope protection wire mesh 10 described above will be described. As shown in FIG. 3 (A), the side where the fiber layer 16 mainly exists is the slope B1 side, and one end of the wound slope net 10 is fixed to the upper end of the slope B1 to be protected. The slope protection wire mesh 10 is developed below the slope B1 to be protected from one end, and is extended to the entire slope B1 (the wire mesh extension process).

Next, as shown in FIG. 4B, the slope protecting wire mesh 10 extended over the entire slope B1 is fixed at a plurality of locations on the slope B1. The slope protecting wire mesh 10 is fixed by engaging the head portion 21a and the slope protecting wire mesh 10 by the head portion 21a straddling the intersection of the constituent wire rods 13 of the slope protecting wire mesh 10, and the anchor pin in the engaged state. 21 is driven from the base 21b into the slope B1. The anchor pin 21 is driven into the slope B1 at a rate of about 1 in 3 m ² .

In addition to the anchor pin 21, an auxiliary pin (not shown) may be driven into the slope B1. The auxiliary pin has the same shape as the anchor pin 21 and has, for example, a diameter φ of about 9 mm and a length of about 20 cm. The auxiliary pins are driven into the slope B1 at a rate of 1.5 per 1 m ² (the wire mesh fixing step).

  The number and length of the anchor pins 21 and the auxiliary pins can be appropriately increased or decreased depending on the weathering depth of the slope surface portion.

  Next, a vegetation base material 22 including plant seeds 20 is sprayed from above the slope protection wire mesh 10 fixed to the slope B1. The thickness of spraying the vegetation base material 22 varies depending on the properties of the vegetation base material 22. When the vegetation base material 22 (that is, a thick-layer base material) including powdered matter, granular materials, and small pieces is sprayed by air conveyance without adding water, the thickness of the sprayed vegetation base material 22 is about 3 to 3. 10 cm. When water is added and the vegetation base material 22 in paste form is kneaded and sprayed by pump conveyance, the thickness of the sprayed vegetation base material 22 is about 1 to 3 cm.

  In the present embodiment, as shown in FIG. 3C, the vegetation base material that has been conveyed by air is sprayed from the front end 23 a of the conveyance hose 23 onto the slope. (End of the seed spraying process).

  4 is a cross-sectional view of the slope B1 protected by the slope protection method according to the present embodiment, and FIG. 5 shows the fiber layer 16 and the layer of the vegetation base material 22 generated between the fiber layer 16 and the slope B1. A cross-sectional shape will be described. 4 is an enlarged view of a portion A in FIG. 3C, and FIG. 5 is a view further enlarging and schematically showing a portion A in FIG. 3C for explaining a cross-sectional shape of the fiber layer 16. FIG. is there. As shown in FIG. 4, the slope protecting wire mesh 10 is fixed on the slope B <b> 1 by anchor pins 21 (see FIG. 3C), and the vegetation base material 22 including the seeds 20 is blown from above the body wire mesh 12. It is attached. A frame structure such as a legal frame is not provided on the slope-protecting wire mesh 10 on which the vegetation base material 22 is sprayed.

Further, as shown in FIG. 5, the surface 16b of the fiber layer 16 on the side of the main body metal mesh 12 is a convex and concave surface including a continuous raised portion 17a and a concave portion 17b. The layer of the vegetation base material 22 has a terraced-like surface portion 16b ₁ that is gentler than the slope of the slope B1 and is almost horizontal.

  Therefore, according to the slope protection wire mesh 10 and the slope protection method using the slope protection wire mesh 10 according to the present embodiment, the main body wire mesh 12 is made of a hard steel wire as the constituent wire 13, so that it is a general purpose made of iron wire. Compared to a metal mesh, it has high spring properties, is difficult to plastically deform, and has high strength. Therefore, the main body metal mesh 12 can firmly cover the surface portion of the slope B1 and prevent erosion of the slope surface portion. Moreover, the erosion of the surface part of slope B1 can further be suppressed by the fiber layer 16 which engages with the constituent wire 13 of the main body metal mesh 12 and has an eye smaller than the mesh of the main body metal mesh 12.

  And since the vegetation base material 22 sprayed from the top of the main body metal mesh 12 penetrates not only into the mesh of the main body metal mesh 12, but also into the fiber layer 16 having an eye smaller than the mesh of the main body metal mesh 12, the slope protecting wire mesh 10 Maintenance of the vegetation base material 22 sprayed on is ensured, and the outflow of the vegetation base material 22 can be prevented.

  Further, as described above, the main body wire mesh 12 uses the wire made of hard steel as the constituent wire rod 13, so that even when the vegetation base material 22 is blown thickly, the sprayed vegetation base is The deformation (so-called sagging) of the main body metal mesh 12 due to the weight of the material 22 does not occur, and the generation of cracks in the thickly sprayed vegetation base material 22 layer and the erosion of the vegetation base material 22 layer due to this crack can be prevented. it can.

  Thus, since the weathered slope B1 surface part is maintained and the vegetation base material 22 is stably held, it is freed from the trouble of separately providing a concrete frame structure, and a concrete frame body is provided. Since it is not necessary to provide a structure, it is also good for the environment.

  Further, as shown in FIG. 4, the fiber layer 16 is mainly present on the slope B1 side, that is, the main part of the fiber layer 16 is pressed against the slope B1 side by the body wire mesh 12, so the body wire mesh 12 This makes it possible to more stably hold the vegetation base material 22 sprayed by the fiber layer 16 fixed to the slope B1 side.

  And since the fiber layer 16 is located below the main body metal mesh 12, the fiber 16a rises from the lower side to the upper side, and has a rising portion that entangles with the constituent wire 13 of the main body metal mesh 12. The sprayed vegetation base material 22 is supported by the rising portion and is held more stably.

  Furthermore, as shown in FIG. 12, when the layer t1 of the vegetation base material 22 is formed by spraying the vegetation base material 22 on the slope B, the roots Ps of the plant in this layer t1 are radiated mainly about the vertically downward axis. Elongate. Therefore, of the radially extending roots, the root portion extending in the direction away from the slope B (see the enclosed box in the figure) is exposed to the outside, the stability of the plant body becomes worse, and the slope of the slope B becomes steep. The more roots exposed to the outside increase. Since plant roots mainly extend vertically downward in accordance with the laws of nature, even if the layer of the vegetation substrate 22 is simply thickened compared to FIG. 12, the proportion of roots exposed to the outside is reduced. I can't.

According to the present embodiment, as shown in FIG. 5, in the surface 16b on the main body metal mesh 12, the layer of the vegetation base material 22 has a terraced-like surface portion 16b ₁ which is gentler than the inclination of the inclined surface B1 and close to the horizontal. doing. That is, even if the slope of the slope becomes steep, such a rice terrace-like surface portion 16b ₁ can be provided on the slope B1, so that the exposure rate of the root Ps of the plant can be reduced and further stabilization of the vegetation can be achieved. It becomes possible.

  The slope protection wire mesh 10 is fixed to the slope B1 by a simple fixing process in which the anchor pin 21 having the main body wire mesh 12 engaged with the head portion 21a is driven into the slope B1, and the slope surface is more easily provided. It is possible to protect the part and secure vegetation.

  In the present embodiment, the anchor pin 21 is used for fixing the slope protecting wire mesh 10 to the slope B1 (that is, the wire mesh fixing step), but the present invention is not limited to this, and various modifications are possible. It is.

  Below, the 1st modification of a wire-mesh fixing process is demonstrated based on FIGS. 6 to 8, the same reference numerals are given to the same elements as those in the embodiment shown in FIGS. 1 to 5 described above, and the description thereof is omitted. 6 is a perspective view of a pressure receiving plate used in a modification of the wire mesh fixing process of the slope protection method, FIG. 7 is a cross-sectional view of a slope for explaining a modification of the wire mesh fixing process of the slope protection method, and FIG. It is a VIII-VIII sectional view taken on the line.

  As shown in FIG. 7, in this modification, the slope B2 is composed of a stabilized formation (deep layer) G1 such as a bedrock and a weathered unstable layer (surface layer) G2 on the deep layer G1. The thickness of the surface layer G2 is not as shallow as the surface portion of the above embodiment, and is generally about 1 to 3 m. There is a slip surface S between the surface layer G2 and the deep layer G1, and the surface layer G2 collapses along the slip surface S, which may cause damage to roads, railways, buildings, and the like in the direction of the collapse.

  In order to prevent such surface slip, in this modification, the long anchor 30 that reaches the deep layer G1 from the slope B2 is used for fixing the slope protection wire mesh 10 to the slope B2 instead of the short anchor pin. The anchor 30 is a rod-like or wire-like long member, and has a length such that the head 30b protrudes on the slope in a state where the base 30a reaches a deep layer G1 of a natural ground described later (see FIG. 7). Specifically, the anchor 30 is a deformed steel bar having a diameter φ of 16 mm to 32 mm, the head 30b is internally threaded, and a cap nut 32 (see FIG. 7) is attached.

  The anchor 30 corresponds to a ground anchor used in a rock bolt or a ground anchor method. In this modification, a lock bolt is employed as the anchor 30.

  Before the cap nut 32 is attached to the head 30b of the anchor 30, a pressure receiving plate 34 that presses the slope protecting wire mesh 10 laid on the slope from above is attached.

  As shown in FIG. 6, the pressure receiving plate 34 is an approximately octagonal steel plate-like body that is horizontally long in a plan view, and has an insertion hole 31 through which the anchor 30 is inserted at the center. The length of the pressure receiving plate 34 shown in the figure in the illustrated horizontal direction is about 200 mm to 500 mm, the length of the pressure receiving plate 34 in the illustrated vertical direction is about 200 mm to 300 mm, and the thickness of the pressure receiving plate 34 is about 10 mm. ~ 20 mm.

  On the lower surface 35 in the vicinity of the corners 34a, 34b, 34c, and 34d of the pressure receiving plate 34, columnar projections 38a, 38b, 38c, and 38d that protrude downward are provided. In addition, the protrusion 38e is shown at the lower left position of the protrusion 38a on the lower surface 35, the protrusion 38f is shown at the lower right position of the protrusion 38b, the protrusion 38g is shown at the upper right position of the protrusion 38c, and the protrusion 38d is shown. A protrusion 38h is provided in the upper left position. The length of the protrusions 38a to 38h is approximately the same as the interval I shown in FIG. 2C, and is generally in the range of 10 mm to 30 mm.

  Hereinafter, a wire mesh fixing process, which is a process of fixing the main body metal mesh 12 to the slope B2, will be described.

  The slope protecting wire mesh 10 has already been provided on the slope B2. In this state, an anchor hole 36 is formed in the slope B2 at a predetermined interval at a position where the anchor 30 is installed. After the anchor 30 is inserted into the anchor hole 36, cement milk 38 is injected into the anchor hole 36, and the anchor 30 is driven into the slope B2. The diameter φ of the anchor hole 36 is in the range of 50 mm to 60 mm. In this state, the anchor base 30a is fixed to the deep layer G1. The head 30b of the anchor 30 is maintained in a state of being exposed to the ground surface.

  Next, the pressure receiving plate 34 is attached to the anchor 30 from above the slope protecting wire mesh 10. The pressure receiving plate 34 is attached to the anchor 30 by inserting the head 30b of the anchor 30 through the insertion hole 31 provided in the pressure receiving plate 34. Then, the pressure receiving plate 34 is pushed down together with the slope protection wire mesh 10 in the direction of the slope B2, and as shown in FIG. 6, the cap nut is attached to the head 30b of the anchor 30 in a state where the slope protection wire mesh 10 is pressed against the slope B2. 32 is screwed and the attachment of the pressure receiving plate 34 to the anchor 30, that is, the wire mesh fixing step of fixing the main body metal mesh 12 at a plurality of points scattered on the inclined surface B <b> 2 while being pressed in the inclined direction is completed.

  8 is a cross-sectional view taken along the line VIII-VIII of FIG. 7, and the pressure receiving plate 34 attached to the anchor 30 from above the slope protecting wire mesh 10 is placed below the slope protecting wire mesh 10 (that is, the slope side). ). In the drawing, the fiber layer 16 is not shown in order to facilitate understanding of the positional relationship between the protrusions 38a to 38h of the pressure receiving plate 34 and the mesh of the main body metal mesh 12, and below the main body metal mesh 12. The mesh located at is shown in black.

  As shown in FIG. 8, the main body metal mesh 12 of the slope protecting wire mesh 10 is arranged such that the bent portion 14c between the side 12a and the side 12b is located above the slope B2 in the inclination direction (in the direction of the arrow H). The bent portion 14c between the side 12c and the side 12d is arranged so as to be below the inclined direction of the inclined surface B2 (in the L arrow direction).

  Then, as shown in the figure, in the state where the wire mesh fixing process is completed, the projecting portions 38a to 38h are formed on the linear portion 13a and the linear upper portion 13b in the vicinity of the bent portion 13c of the constituent wire 13 constituting the rhombus mesh. They are in contact with each other and inserted into the mesh.

  That is, of the eight protrusions 38a to 38h, the four protrusions 38a, 38b, 38g, and 38h are in contact with the corners 40a (intersections) at the top of the slope in the mesh that is inserted. Yes. In addition, the side portions of the remaining four protrusions 38c, 38d, 38f, and 38e out of the eight protrusions 38a to 38h are in contact with the corner 40b (intersection) at the bottom of the slope in the mesh that is inserted therethrough. doing.

  Thereafter, a seed spraying process is performed as in the above embodiment, and no frame structure is provided on the slope protecting wire mesh 10.

According to this modification, unlike the general purpose wire mesh based on commercial iron wire (tensile strength 290~540N / mm ^2), the body of hard steel wires having a tensile strength of 800~2000N / mm ² as a wire 13 The metal mesh 12 is configured, and the main body metal mesh 12 is pressed in the direction of the slope B2 by the pressure receiving plate 34 fixed to the upper end 30b of the anchor 30. Therefore, not only can the weathered surface portion of the slope B2 be protected and the vegetation of the entire slope be secured, but also the surface slip to a depth of 1 to 3 m deeper than the slope surface portion (ie, the surface layer). G2 slip) can also be prevented.

  Furthermore, in the region below the pressure receiving plate 34 in the slope protection wire mesh 10 laid out on the slope B2, the slope B2 is inclined upward (in the direction of arrow H in FIG. 8) and downward (in the direction of arrow L in FIG. 8). A strong tensile force acts. Therefore, when the slope protection wire mesh 10 is pulled upward in the inclination direction in the surface spreading direction of the wire mesh, the stress on the anchor 30 is concentrated at the corner (intersection) at the bottom of the slope in the mesh through which the anchor 30 is inserted. . Further, when the slope protection wire mesh 10 is pulled downward in the inclination direction in the surface spreading direction of the wire mesh, stress on the anchor concentrates at the corner (intersection) of the uppermost slope of the mesh through which the anchor 30 is inserted.

According to this modification, in a state where the pressure receiving plate 34 is fixed to the upper end 30b of the anchor 30, the mesh through which the anchor 30 in the slope protecting wire mesh 10 in which the protrusions 38a to 38h are extended on the slope B2 is inserted. Is inserted into another mesh, and the side portions of the projections 38a, 38b, 38g and 38h are close to the corner (intersection) 40a at the uppermost slope of the mesh, and the projections 38c, 38d, The side portions of 38e and 38f are close to the lowermost corner (intersection) 40b of the mesh.
Therefore, when the slope protection wire mesh 10 is pulled downward in the slope inclination direction (in the direction of the arrow L in FIG. 8), the side portions of the projections 38a, 38b, 38g, and 38h and the anchor 30 are respectively connected to the mesh corners (intersection points). ) Immediately, and when the slope protection wire mesh is pulled upward (in the direction of arrow H in FIG. 8), the side portions of the projections 38c, 38d, 38e and 38f and the anchor 30 are The stress that quickly contacts the corner (intersection point) 40b and acts on the slope protecting wire mesh 10 is quickly and reliably dispersed.

  Thereby, the breakage / damage of the slope protection wire mesh 10 at the mesh portion (40a and 40b) with which the anchor 30 abuts is suppressed, and the slope protection wire mesh 10 can exhibit a greater earth pressure receiving force. Become. That is, by combining with the pressure receiving plate 34 having the protrusions 38a to 38h, it is possible to improve the ability to protect the slope surface by the slope protection wire mesh 10 without changing the wire mesh itself.

  Furthermore, since the frame structure is not provided on the slope protection wire mesh 10, it is possible to protect the entire slope B2 more easily than in the past.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention. For example, in the above modification, the bottom surface 35 of the pressure receiving plate 34 is provided with eight columnar projections, but the present invention is not limited to this. FIG. 9 is a view corresponding to the cross-sectional view taken along the line VIII-VIII in FIG. 7 for explaining another aspect of the protrusion according to the modification. Also in this figure, like FIG. 8, in order to facilitate understanding of the positional relationship between the protrusions of the pressure receiving plate and the mesh of the metal net body 12, the fiber layer 16 is not shown and is positioned below the main metal mesh 12. The mesh to be painted is shown in black.

  As shown in the figure, cylindrical protrusions 50 a to 50 m are provided on the entire lower surface 35 of the pressure receiving plate 34. The protrusions 50a to 50m are substantially similar to the mesh shape in the lower region (shown in black) of the pressure receiving plate 34 in a state where the pressure receiving plate 34 is fixed to the upper end 30b of the anchor 30, and the protrusion 50a. The side portions of the protrusions 50 a to 50 m are close to the mesh in the lower region of the pressure receiving plate 34 with ˜50 m inserted through each mesh.

  In other words, from a different viewpoint, the projections 50a to 50m have a mesh shape in which the mesh side of the main body metal mesh 12 in the lower region (shown in black in the drawing) of the pressure receiving plate 34 is formed on the lower surface 35 of the pressure receiving plate 34. A groove portion 52 that can be fitted while being maintained is configured.

  Therefore, according to another aspect of the present modification, the horizontal cross-sectional shape of the protrusions 50a to 50m is substantially similar to the mesh shape in the lower region (shown in black in the drawing) of the pressure receiving plate 34, and in the inserted state. Since the side portions of the protrusions 50a to 50m are close to each side of the mesh, a strong tensile force acts on the mesh body 20 in the upward direction (in the direction of the arrow H) and downward (in the direction of the arrow L). In this case, stress is dispersed to the maximum extent not only in the mesh through which the anchor 30 is inserted, but also in each side and each corner (intersection) of each mesh through which the protrusions 50a to 50m are inserted.

  Thereby, by the combination with the pressure receiving plate 34 having the protrusions 50a to 50m, it is possible to maximize the ability to protect the slope surface by the slope protection wire mesh 10 without changing the wire mesh itself.

  Furthermore, in the above embodiment, the fiber layer 16 is formed by fusing polyethylene fibers (fibers 16a) immediately after spinning to the polyethylene fibers spun one after another, but is not limited thereto. .

  For example, when coconut fibers are used as the fibers, the fiber layers can be formed by bonding the coconut fibers together with an adhesive or the like. In the integration of the main body metal mesh 12 and the fiber layer, an adhesive may be used in the same manner, or another engagement member may be used.

  Further, in the above-described modification, the anchor 30 is driven on the slope B2 after the wire netting step, but the present invention is not limited to this. For example, before the slope protection wire mesh 10 is placed on the slope B2. The anchor 30 may be driven on the slope B2.

  Moreover, in the said embodiment, although a rhombus metal mesh is used as the main body metal mesh 12, it is not restricted to this. For example, a ring net formed by connecting a large number of ring members made of a turtle shell metal mesh or an annular component wire so that the inner peripheral sides of adjacent ring members are in contact, etc. Any wire mesh may be used as long as it is made of a constituent wire having tensile strength.

DESCRIPTION OF SYMBOLS 10 Wire mesh for slope protection 12 Main body metal mesh 13 Constituent wire 16 Fiber layer 17a Raised part 17b Depressed part 20 Seed 21 Anchor pin (pin)
22 Vegetation base material 30 Anchor 34 Pressure receiving plate 38a, 38b, 38c, 38d, 50a, 50b, 50c, 50d, 50e, 50f, 50g, 50h, 50i, 50j, 50k, 50l, 50m Protruding part B1, B2 Slope

Claims (8)

The main body wire mesh that covers the surface of the slope to be protected, using a hard steel wire as a constituent wire,
A slope protecting wire mesh, comprising: a fiber layer that engages with a constituent wire of the body wire mesh and has an eye smaller than the mesh of the body wire mesh.   The fiber layer is engaged with the main body metal mesh so that the fibers constituting the fiber layer are entangled with the constituent wire of the main body metal mesh so that the fiber layer mainly exists on the inclined surface side of the main body metal mesh. A wire mesh for slope protection, characterized by being done. The construction wire is slope protective wire net according to claim 1 or 2, characterized in that it has a tensile strength of 800~2000N / mm ^2.   The slope protection according to any one of claims 1 to 3, wherein at least a surface of the fiber layer in the slope installation state on the side of the main body metal mesh is an uneven surface in which a raised portion and a dent portion are continuous. Wire mesh. In the slope protection method using the slope protection wire mesh according to any one of claims 1 to 4,
The wire mesh extending step of extending the slope protecting wire mesh on the entire slope to be protected, with the side where the fiber layer mainly exists as the slope side;
A wire mesh fixing step of fixing the spread slope protecting wire mesh at a plurality of locations scattered with respect to the slope;
Spraying a vegetation base material containing at least plant seeds from above the slope protection wire mesh fixed to the slope, and
A slope protecting method, wherein no frame structure is provided on the slope protecting wire mesh. The wire mesh fixing step includes
The slope protection according to claim 5, wherein the slope protection is performed by driving a pin having an engaging portion engageable with the main body metal mesh on the head in a state where the main body metal mesh is engaged with the head. Method. The wire mesh fixing step includes
A pressure receiving plate capable of interstitially pressing a predetermined range of the main body metal mesh to the upper end of the anchor placed on the slope in a state where the upper end protrudes from the slope in the dotted locations, and the main body metal mesh in the direction of the slope The slope protecting method according to claim 5, wherein the slope protecting method is performed by fixing in a pressed state. The pressure receiving plate has one or a plurality of protrusions protruding from one surface,
The wire mesh fixing step includes
The projecting portion of the pressure receiving plate is a mesh different from the mesh through which the anchor is inserted, and the side portion of the projecting portion is at least close to both the uppermost slope and the lowermost slope of the other mesh. Let it through,
The slope protecting method according to claim 7, wherein the pressure receiving plate is fixed by fixing the main body metal mesh in a state where the body metal mesh is pressed in the slope direction.

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