Rockfall protection and avalanche prevention shared fence

Abstract

The present invention provides a fence used for both rockfall protection and avalanche prevention, the fence being capable of efficiently absorbing rockfall energy and preferably serving as a protection fence having functions for both rockfall protection and avalanche prevention.　A fence 1 used for both rockfall protection and avalanche prevention includes: terminal posts 11 erected at two end sections; a face material 13 that is secured to the terminal posts 11 and expanded between the terminal posts 11; an intermediate post 12 disposed between the terminal posts 11; and an attaching wire fence 14 that is a wire fence that attaches the face material 13 to the intermediate post 12 so as to be fixed thereto, wherein the breaking load of said fixing is lower than the breaking load of the face material 13.

Description

Technical Field

[0001] The present invention relates to a fence that can be used in common as a rockfall protection fence and an avalanche prevention fence.

Background Art

[0002] In order to protect roads, houses, etc. from rockfalls on slopes, etc., a protection fence (rockfall protection fence) installed on the slope side of the roads, houses, etc. to be protected is used. A general rockfall protection fence has a structure in which an upper member composed of a support column, a wire rope, and a wire mesh is supported by a concrete foundation, thereby receiving rockfalls from above the slope and preventing disasters. Such a rockfall protection fence is disclosed by Non-Patent Document 1. In addition, technologies related to rockfall protection fences improved so as to be able to widen the range of the energy absorption ability of rockfalls are disclosed by Patent Document 1 and Patent Document 2.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In snowy regions, in addition to protecting against rockfalls on slopes, avalanche prevention is also necessary, and from the perspective of economy, etc., in some cases, one protective fence is made to have both the functions of rockfall protection and avalanche prevention. The protective facilities disclosed in Patent Documents 1 and 2 can also be used as rockfall protection fences and avalanche prevention fences.

[0006] An object of the present invention is to provide a combined rockfall protection and avalanche prevention fence that can efficiently absorb the energy of rockfalls and is more suitable as a protective fence having both the functions of rockfall protection and avalanche prevention.

Means for Solving the Problems

[0007] (Configuration 1) Terminal supports erected at both ends, a facing material fixed to the terminal supports and deployed between the terminal supports, intermediate supports arranged between the terminal supports, and a wire mesh for fixedly attaching the facing material to the intermediate supports, wherein the breaking load of the fixing is smaller than the breaking load of the facing material. A combined rockfall protection and avalanche prevention fence comprising an attachment wire mesh.

[0008] (Configuration 2) When receiving the snow pressure due to snow accumulation, the sliding of the facing material with respect to the intermediate support is suppressed by the attachment wire mesh, and when receiving a predetermined impact energy at the time of a rockfall collision, the fixing by the attachment wire mesh is broken, and the facing material is configured to slide with respect to the intermediate support. The combined rockfall protection and avalanche prevention fence according to Configuration 1.

[0009] (Configuration 3) The combined rockfall protection and avalanche prevention fence according to Configuration 1 or 2, wherein the breaking load of the attachment wire mesh is smaller than the breaking load of the facing material.

[0010] (Configuration 4) The combined rockfall protection and avalanche prevention fence according to Configuration 1 or 2, comprising an attachment member for attaching the attachment wire mesh to the facing material, and the breaking load of the attachment member is smaller than the breaking load of the facing material.

[0011] (Configuration 5) The rockfall protection and avalanche prevention shared fence according to Configuration 1 or 2, wherein the breaking load of the fixing of the mounting wire mesh is adjusted according to the vertical mounting range of the mounting wire mesh.

[0012] (Configuration 6) The rockfall protection and avalanche prevention shared fence according to any one of Configurations 1 to 5, comprising a backup wire mesh attached to the facing material so that the breaking load is a wire mesh equal to or greater than that of the facing material, and the facing material can slide relative to the intermediate support by a predetermined distance.

[0013] (Configuration 7) The rockfall protection and avalanche prevention shared fence according to Configuration 6, wherein when receiving a predetermined impact energy at the time of a rockfall collision, the fixing by the mounting wire mesh breaks, and the backup wire mesh slides the facing material by the predetermined distance.

[0014] (Configuration 8) The rockfall protection and avalanche prevention shared fence according to Configuration 6 or 7, wherein the rockfall protection and avalanche prevention shared fence is provided on a slope or in the vicinity thereof, the facing material is arranged on the upper side of the slope with respect to the intermediate support, and the backup wire mesh is attached to the facing material so as to surround the intermediate support from the lower side of the slope.

Advantages of the Invention

[0015] According to the present invention, it is possible to provide a rockfall protection and avalanche prevention shared fence that is more suitable as a protection fence having both functions of rockfall protection and avalanche prevention.

Brief Description of the Drawings

[0016]

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Mode for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. The following embodiments are one form when embodying the present invention and do not limit the present invention within its scope.

[0018] <Embodiment 1> FIG. 1 is a front view (viewed from the lower side of the slope) showing the outline of the rockfall protection and avalanche prevention shared fence (hereinafter simply referred to as "shared protection fence") of Embodiment 1. FIG. 2 is a schematic diagram showing the configuration when viewed planarly at the location where the intermediate support column 12 of the shared protection fence 1 is present. The shared protection fence 1 of the present embodiment functions as a rockfall protection fence provided on the slope side of the road or house to be protected in order to protect the road, house, etc. from rockfall, etc. on a slope or the like (slope or its vicinity), and at the same time also functions as an avalanche prevention fence for suppressing the occurrence of avalanches. The shared protective fence 1 of this embodiment includes terminal columns 11 erected at both ends, a wire mesh 13 which is a surface material fixed to the terminal columns 11 and deployed between the terminal columns at both ends, intermediate columns 12 arranged between the terminal columns 11, and a mounting wire mesh 14 which fixedly attaches the wire mesh 13 to the intermediate columns 12 and whose breaking load for fixing is smaller than the breaking load of the surface material 13.

[0019] The terminal columns 11 are composed of, for example, H-shaped steel and are supported by a concrete foundation. Note that any terminal column having the required strength can be used, and any structure (foundation) that generates the required supporting force (for example, instead of a concrete foundation, a structure that supports the column with piles or anchor bolts, etc.) can be used. In this embodiment, a support member 111 and a mounting member 112 for fixing the wire mesh 13 are provided on the terminal columns 11. The support member 111 is a support member for resisting the force that causes the wire mesh 13 to be pulled when receiving a falling rock impact, thereby causing the terminal column 11 to fall inward. When the strength obtained by the terminal column itself (and the foundation) is sufficient, the support member 111 is not necessarily required. The mounting member 112 is a steel material bolted to the web of the terminal column 11 which is H-shaped steel, and the end of the wire mesh 13 is fixed to the mounting member 112. In this embodiment, the wire mesh 13 is horizontally deployed (arranged such that the column wires constituting the wire mesh are in the vertical direction) and is attached to the terminal column 11 via the mounting member 112. Note that the mounting member 112 can use any configuration that can fixedly attach the wire mesh to the terminal column with the required strength, and it may also be a structure that directly fixes the wire mesh to the terminal column (without providing a separate mounting member).

[0020] The intermediate support 12 is formed of a steel pipe in this embodiment and is arranged at a predetermined interval (for example, every 1 m to 10 m) between the terminal supports 11. As shown in FIG. 2 (the upper side of FIG. 2 corresponds to the upper side of the slope, and the lower side corresponds to the lower side of the slope), the intermediate support 12 is arranged on the lower side of the slope with respect to the wire mesh 13. Similar to the terminal support, any intermediate support having the required strength can be used, and any structure (foundation) for supporting it can also be used as long as it can generate the required supporting force (for example, instead of a concrete foundation, a structure that supports the support with piles or anchor bolts, etc.). The intermediate supports are provided in a number determined according to the full width of the shared protection fence 1 and the span (distance between supports).

[0021] As shown in FIGS. 1 and 2, the attachment wire mesh 14 is attached to the wire mesh 13 so as to surround the intermediate support 12 from the lower side of the slope. The attachment is performed by an attachment member 16 for attaching the attachment wire mesh 14 to the wire mesh 13. Examples of attachment by the attachment member 16 include, for example, those that fasten the attachment wire mesh 14 and the wire mesh 13 by winding them using a binding coil, and those that fasten the attachment wire mesh 14 and the wire mesh 13 by weaving them with the row wires of the wire mesh. However, it is not limited to these, and any method that can fasten the attachment wire mesh and the facing material with the required strength can be used. As will be described below, the attachment wire mesh 14 is for suppressing the sliding of the wire mesh 13 with respect to the intermediate support 12 when receiving the snow pressure due to snow accumulation. Therefore, it is attached so as to fix the wire mesh 13 to the intermediate support 12 (to prevent the wire mesh 13 from shifting with respect to the intermediate support 12 in the unfolding direction of the fence (the left - right direction in FIGS. 1 and 2)). Moreover, in the attachment wire mesh 14 of this embodiment, the tensile strength of the row wires constituting the wire mesh is lower than the tensile strength of the row wires of the wire mesh 13. Therefore, the breaking load of the attachment wire mesh 14 is smaller than the breaking load of the wire mesh 13. Thus, when receiving a predetermined impact energy during a rockfall collision, the attachment wire mesh 14 breaks, and the wire mesh 13 is configured to slide with respect to the intermediate support 12. Note that the attachment member 16 has a strength such that the breaking load of the attachment portion by the attachment member 16 is at least greater than the breaking load of the attachment wire mesh 14.

[0022] FIG. 3 is a schematic plan view for explaining a state in which the shared protective fence 1 receives falling rocks. As described above, since the mounting wire mesh 14 is configured to break when receiving a predetermined collision energy at the time of a falling rock collision, when the wire mesh 13 receives the falling rock, the fixing of the wire mesh 13 to the intermediate support by the mounting wire mesh 14 breaks, and the wire mesh 13 can slide with respect to the intermediate support 12. That is, the impact energy of the falling rock is efficiently propagated over the entire length of the wire mesh 13, and the impact energy can be absorbed over the entire length of the wire mesh 13 (note that depending on the collision energy, the energy does not necessarily propagate over the entire length of the wire mesh). When the wire mesh receives the impact energy of the falling rock, elongation occurs due to its structural deformation (such as mesh deformation) and the elongation of the wire itself constituting the wire mesh. At this time, energy is consumed by the plastic deformation and friction between members that occur, and the collision energy is absorbed by these, but this effect can be generated over the entire length in the width direction of the wire mesh. In a conventional protective fence, usually, the wire mesh is directly or indirectly fixed to the intermediate support, and there is no concept of intentionally breaking the fixing, so the collision energy is concentrated only on a specific span where the falling rock hits. Therefore, each member needs to have a strength sufficient to withstand this. However, according to the shared protective fence 1 of the present embodiment, since it is possible to absorb energy (disperse energy) throughout the entire fence, an excellent effect can be obtained in that it is also possible to suppress the specifications of each member. In addition to such an effect of "absorbing energy throughout the entire fence", energy absorption also occurs in the mounting wire mesh 14 and its mounting members 16 when the mounting wire mesh 14 breaks, so a higher energy absorption capacity can be obtained. Note that the setting of the breaking load of the mounting wire mesh 14 (that is, the setting of the "predetermined collision energy at the time of a falling rock collision") is appropriately determined based on the design concept and specifications of each shared protective fence. When there is a falling rock that does not reach the "predetermined collision energy", the mounting wire mesh 14 does not break, and the falling rock is received by the shared protective fence 1.

[0023] On the other hand, when using the snow fence to hold back the snow accumulation, if the wire mesh 13 slides freely, it may cause inconvenience. Snow accumulation in the natural environment is not necessarily uniform due to the influence of terrain and the like. For example, the amount of snow accumulation may locally increase due to snowdrifts. When such a bias occurs, as conceptually shown in Fig. 4(a), a larger load is applied to a specific span compared to others at the initial stage of snowfall. As a result, in the corresponding span, the wire mesh may bend significantly. Furthermore, as the snowfall progresses, there is a risk that the span that has bent significantly earlier will receive an additional snow load, leading to damage to the members. To address such problems, in the shared protection fence 1 of this embodiment, as can be understood from Fig. 4(b), since the wire mesh 13 is fixed to the intermediate support 12 by the mounting wire mesh 14, it is possible to reduce the significant bending of the wire mesh 13 in a specific span due to the bias of snow accumulation. Thus, it has the function of equalizing the bending of each span of the wire mesh 13.

[0024] As described above, according to the shared protection fence 1 of this embodiment, the energy of falling rocks can be efficiently absorbed, and even in an environment where there is a bias in the amount of snow accumulation, it is possible to reduce the significant bending of the wire mesh in a specific span. Therefore, it is possible to provide a falling rock protection and avalanche prevention shared fence that is more suitable as a protection fence having both the functions of falling rock protection and avalanche prevention. In addition, since the number of components is relatively small and inexpensive components such as wire meshes are used, it is possible to provide a falling rock protection and avalanche prevention shared fence at low cost.

[0025] <Embodiment 2> Fig. 5 is a front view (viewed from the lower side of the slope) showing the outline of the shared protection fence 2 of Embodiment 2. Fig. 6 is a schematic diagram showing the configuration as viewed in plan at the location where the intermediate support 12 of the shared protection fence 2 is present. Note that for those having the same configuration as the shared protection fence 1 of Embodiment 1, the same reference numerals are used, and the description here is omitted or simplified.

[0026] The shared protective fence 2 of this embodiment is different from the shared protective fence 1 of Embodiment 1 in that it is provided with a backup wire mesh 15. The backup wire mesh 15 is such that the tensile strength of the column wires constituting the wire mesh is equal to or greater than the tensile strength of the column wires of the wire mesh 13. Therefore, the breaking load of the backup wire mesh 15 is equal to or greater than the breaking load of the wire mesh 13. (In this embodiment, the backup wire mesh 15 and the wire mesh 13 use the same wire mesh.) As can also be understood from FIG. 6 (the upper side of FIG. 6 corresponds to the upper side of the slope, and the lower side corresponds to the lower side of the slope), the backup wire mesh 15 is attached to the wire mesh 13 so as to surround the intermediate support column 12 from the lower side of the slope. Further, the backup wire mesh 15 is attached to the wire mesh 13 with an extra length so that the wire mesh 13 can slide by a predetermined distance with respect to the intermediate support column 12 (slideable in the unfolding direction of the fence (the left - right direction in FIGS. 5 and 6)). The breaking load of the attachment part is configured to have a breaking load equal to or greater than that of the backup wire mesh 15. The attachment of the backup wire mesh 15 to the wire mesh 13, similar to the attachment method of the attachment wire mesh 14 in Embodiment 1, can be performed not only by attachment members 17 such as binding coils and column wires, but also by any method that can fasten the backup wire mesh and the facing material with the required strength.

[0027] FIG. 7 is a schematic plan view for explaining the state of receiving falling rocks in the shared protective fence 2 of this embodiment. As described in Embodiment 1, since the attachment wire mesh 14 is configured to break when receiving a predetermined impact energy during the impact of falling rocks, when the wire mesh 13 receives the falling rocks, the fixing of the wire mesh 13 to the intermediate support column by the attachment wire mesh 14 breaks. On the other hand, the backup wire mesh 15 has the same strength as the wire mesh 13 and does not break at the collision energy within the specification range of the fence. However, as described above, since the backup wire mesh 15 is attached so that the wire mesh 13 can slide relative to the intermediate support 12 by a predetermined distance, the wire mesh 13 that receives the falling rock slides. That is, "when receiving a predetermined collision energy at the time of collision of a falling rock, the fixing by the mounting wire mesh breaks, and the backup wire mesh is configured to slide the facing material by a predetermined distance." Thereby, the same effects as those of the first embodiment (effects such as "absorbing energy throughout the fence") can be obtained. Furthermore, according to the shared protection fence 2 of the present embodiment, due to the presence of the backup wire mesh 15, an effect of more reliably capturing falling rocks can also be obtained. For example, when a falling rock hits the intermediate support 12 directly, the wire mesh 13 may be sandwiched between the falling rock and the intermediate support 12 and break (break by shear rather than tension). Even in such a case, since the backup wire mesh 15 having the same or higher strength as the wire mesh 13 is connected in parallel, it is possible to more reliably capture the falling rock.

[0028] FIG. 8 is an explanatory diagram for explaining the function when receiving snow accumulation in the shared protection fence 2 of the present embodiment. Similar to the first embodiment, since the wire mesh 13 is fixed to the intermediate support 12 by the mounting wire mesh 14, the large deflection of the wire mesh 13 in a specific span due to the snow accumulation bias is reduced, and the deflection of each span of the wire mesh 13 is made uniform.

[0029] As described above, according to the shared protection fence 2 of the present embodiment, the same operational effects as those of the first embodiment can be obtained, and due to the presence of the backup wire mesh 15, an effect of more reliably capturing falling rocks can also be obtained.

[0030] In the embodiment, as shown on the left side of FIG. 9, an example is given in which the mounting wire mesh 14 and the backup wire mesh 15 are provided in the same height range as the support column 12 (or the wire mesh 13), but the present invention is not limited thereto. For example, as illustrated in the center of FIG. 9 (the mounting wire mesh has two upper and lower stages, and the backup wire mesh is in the center) or on the right side (the mounting wire mesh is provided in the center, and the backup wire mesh is in two upper and lower stages), they can be installed in any height range, and can also be provided separately at a plurality of locations such as in two upper and lower stages. Such changes in the attachment range and position are effective also in cases where local snow accumulation is expected, such as when the arrangement of the support columns cannot be arranged linearly in a plane, when there are vertical steps, etc., or when there are differences in snow accumulation due to terrain or slope gradient.

[0031] In the embodiment, an example is given in which the breaking load of the mounting wire mesh 14 is made smaller than that of the wire mesh 13 by making the tensile strength of the column wires constituting the mounting wire mesh 14 lower than the tensile strength of the column wires of the wire mesh 13, but the present invention is not limited thereto. As another method of making the breaking load of the mounting wire mesh 14 smaller than that of the wire mesh 13, for example, by changing the structure of the wire mesh weaving (making the mesh size of the mounting wire mesh 14 larger than that of the wire mesh 13, making the wire diameter of the mounting wire mesh 14 smaller (thinner) than the wire diameter of the wire mesh 13, etc.), or by changing the mounting range of the wire mesh in the vertical direction (changing as illustrated in FIG. 9). According to the method of changing the mounting range of the mounting wire mesh 14 (making the mounting wire mesh 14 smaller) as shown in FIG. 9, while using a common wire mesh itself, it is possible to "make the breaking load of the mounting wire mesh smaller than that of the wire mesh", so that the commonality of the members can be achieved.

[0032] Also, in the embodiment, an example is given in which the fixing by the mounting wire mesh is broken when receiving a "predetermined collision energy" by making the breaking load of the mounting wire mesh 14 smaller than that of the wire mesh 13, but the present invention is not limited thereto. For example, the breaking load of the attachment portion of the attachment member 16 composed of a coupling coil or the like may be made smaller than the breaking load of the wire mesh 13. That is, when receiving a "predetermined collision energy", the attachment portion may be configured to break so that "the fixation by the attachment wire mesh is broken". The setting of the breaking load of the attachment portion of the attachment member 16 may be adjusted by, for example, the attachment length or the number of turns of the coupling coil, in addition to the selection of the material of the attachment member 16 such as the coupling coil, in the same manner as described for the attachment range of the attachment wire mesh 14 in FIG. 9.

[0033] In the embodiment, an example is given in which the respective ends of the attachment wire mesh 14 and the backup wire mesh 15 are fastened to the wire mesh 13 at different positions, but the present invention is not limited thereto. For example, as illustrated in FIG. 10(a), the ends of the attachment wire mesh 14 and the backup wire mesh 15 may be attached to the wire mesh 13 at the same position (it may be at the same position only at one end, not both ends). In this case, the attachment wire mesh 14 and the backup wire mesh 15 may be attached by the same attachment member 17 (such as a coupling coil).

[0034] In the embodiment, an example is given in which the backup wire mesh 15 is attached outside the attachment wire mesh 14, but the present invention is not limited thereto. For example, as illustrated in FIG. 10(b), a backup wire mesh 15 may be attached inside the attachment wire mesh 14. Even in this case, it is possible to attach the backup wire mesh 15 to the wire mesh 13 with an extra length. At this time, the backup wire mesh 15 may be a "plain weave (hiratori)" with both ends of the wire mesh left "uncut" so that the extra length portion of the backup wire mesh 15 fits well. If both ends of the wire mesh are left "uncut" so that the elementary wires (row wires) are not fastened to each other, the elementary wires (row wires) are released, and thus it is possible to fold them by sliding the elementary wires (row wires) relative to each other (the folded portions 151, 152 in FIG. 10(b)). In this way, after the backup wire mesh 15 is installed with an extra length, it is possible to attach the attachment wire mesh 14 from the outside so as to suppress the sliding of the wire mesh 13 with respect to the intermediate support 12.

[0035] The length of the extra length when attaching the backup wire mesh to the wire mesh is appropriately determined based on the specifications and design concept of the fence, etc., but the length may be changed according to the position with respect to the terminal support. The sliding amount of the wire mesh during a rockfall impact tends to be larger at a location farther from the terminal support (near the center of the fence) than near the terminal support (where the wire mesh is fixed). Therefore, by increasing the length of the extra length provided in the backup wire mesh as the distance from the terminal support increases, the effect of "absorbing energy throughout the fence" described above can be obtained more efficiently.

[0036] It is not necessary to provide the attachment wire mesh and the backup wire mesh for all the intermediate supports. For example, the attachment wire mesh may not be provided for the intermediate supports close to the terminal support, or the attachment wire mesh may be provided for the intermediate supports at predetermined intervals or for every predetermined number. Also, in the installation environment of the shared protection fence, if it is known in advance that there are locations where the snow accumulation amount will be large, the attachment wire mesh may be provided only for the intermediate supports installed in the vicinity.

[0037] Note that as the wire mesh 13, any wire mesh that can meet the specifications as a rockfall protection fence and an avalanche prevention fence can be used (considering the function as a rockfall protection fence, for example, a high-strength wire mesh of 1000 N / mm 2 or more is preferably used). The energy absorption facing material and the energy absorption device disclosed in Patent Document 1 and Patent Document 2 can also be used. Further, a reinforcing member for reinforcing the upper and lower portions of the facing material may be provided as necessary. On the other hand, as the mounting wire mesh, for example, an ordinary wire mesh of about 400 N / mm 2 can be used. In the embodiment, an example is given in which the wire mesh 13 is attached to the terminal support 11 in a horizontal deployment (arrangement such that the column wires constituting the wire mesh are in the vertical direction), but the wire mesh may be in a vertical deployment (arrangement such that the column wires are in the horizontal direction).

Explanation of Reference Numerals

[0038] 1...Rockfall protection and avalanche prevention shared fence 11...Terminal support 12...Intermediate support 13...Wire mesh (facing material) 14...Mounting wire mesh 15...Backup wire mesh 16, 17...Mounting members

Claims

1. Terminal supports erected at both ends, A surface material fixed to the terminal supports and deployed between the terminal supports, Intermediate supports arranged between the terminal supports, A wire mesh for fixedly attaching the surface material to the intermediate supports, the breaking load of the fixation being smaller than the breaking load of the surface material and configured not to break when receiving snow pressure due to snow accumulation, the mounting wire mesh, comprising, When receiving snow pressure due to snow accumulation, sliding of the surface material with respect to the intermediate supports is suppressed by the mounting wire mesh, A rockfall protection and avalanche prevention shared fence configured such that when receiving a predetermined impact energy during a rockfall collision, the fixation by the mounting wire mesh is broken and the surface material slides with respect to the intermediate supports.

2. The intermediate supports are arranged on the lower side of the slope with respect to the surface material, The mounting wire mesh is attached to the surface material so as to surround the intermediate supports from the lower side of the slope. The rockfall protection and avalanche prevention shared fence according to claim 1.

3. The breaking load of the mounting wire mesh is smaller than the breaking load of the surface material. The rockfall protection and avalanche prevention shared fence according to claim 1 or 2.

4. It comprises a mounting member for attaching the mounting wire mesh to the surface material, and the breaking load of the mounting member is smaller than the breaking load of the surface material. The rockfall protection and avalanche prevention shared fence according to claim 1 or 2.

5. The breaking load of the fixation of the mounting wire mesh is adjusted by the vertical mounting range of the mounting wire mesh. The rockfall protection and avalanche prevention shared fence according to claim 1 or 2.

6. A wire mesh having a breaking load equal to or greater than that of the surface material, and a backup wire mesh attached to the surface material so that the surface material can slide a predetermined distance with respect to the intermediate supports. The rockfall protection and avalanche prevention shared fence according to any one of claims 1 to 5. Claim 7 When receiving a predetermined impact energy during a rockfall collision, the fixing by the attachment wire mesh breaks, and the backup wire mesh is configured to slide the facing material by the predetermined distance. The rockfall protection and avalanche prevention shared fence according to claim 6. Claim 8 The rockfall protection and avalanche prevention shared fence is provided on a slope or in its vicinity, and the facing material is arranged on the upper side of the slope with respect to the intermediate support. The backup wire mesh is attached to the facing material so as to surround the intermediate support from the lower side of the slope. The rockfall protection and avalanche prevention shared fence according to claim 6 or 7.

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