Guard fence and guard fence construction method

Abstract

To provide a guard fence having high functionality (having a high load distribution function) while avoiding the use of an extremely special configuration in the guard fence of a type in which a blocking surface is stretched between a support and an anchor installed on a mountain side from the support.SOLUTION: A guard fence 1 which is installed on a slope, comprises: a plurality of supports 12; anchors which are provided on a mountain side of the support 12; a face material 11 which is stretched between an upper part of the support 12 and the anchor, and comprises a wire mesh having a substantially rectangular outer shape and one face material cable body passed through three peripheral sides of the wire mesh including at least one side of the wire mesh disposed on the upper part of the support 12; and an upper side cable body 15 which is a cable body arranged in the upper part of the support 12 and fastened to the face material 11 and is annularly provided so as to reciprocate between the adjacent supports 12, and in which the face material 11 is fastened to one of the reciprocation.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a safety fence to be installed on sloping ground. [Background technology]

[0002] One type of protective facility is a guard fence, and guard fences made of cables such as wire ropes or mesh such as wire mesh (or guard fences made of both cables and mesh), or guard fences made of beam-shaped members are used to keep objects within a specified area. One type of protective fence has a blocking surface with a flexible structure that is suspended between a support post and an anchor installed on the mountain side of the support post. Conventional techniques relating to such rockfall protection fences are disclosed in Patent Documents 1 to 4. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-322615 A [Patent Document 2] Patent No. 6996801 [Patent Document 3] Patent No. 7079542 [Patent Document 4] Patent No. 5236104 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent documents 1 to 3 are protective fences that use a "triangular net" made by crossing and knitting wires such as steel wires and wire ropes as a blocking surface. In contrast, as explained in paragraph 0004, Patent document 4 describes a protective fence that uses a semi-finished free net, addressing the issue of the labor and cost involved in manufacturing the "triangular net." It is explained that the protective fence with a semi-finished free net in Patent Document 4 has a hemispherical base at the bottom of the support pillar body, so that when an axial force acts on the support pillar, the support pillar rotates and the load balance of the entire protective fence can be automatically adjusted.Furthermore, it is explained that in a protective fence with supports that allow such rotation (change in inclination), an open frame rope having continuity is moored so as to be able to slide freely relative to the mountain side anchor, so that when the distance between the top of the support pillar and the mountain side anchor changes as the support pillar rotates at an angle, the open frame rope slides and can automatically adjust the side length of the open frame rope in accordance with the change in the length of the left and right sides of the net. The semi-finished protective fence with free net described in Patent Document 4 has the above-mentioned functions, but in order to do so it requires rather special supports with hemispherical bases at the bottom. If special posts are required, the costs will be high because special parts will be required, and their installation may require the worker to have specialized knowledge, which is undesirable from these perspectives. Therefore, there is a demand for protective fences that have high functionality while avoiding the use of extremely special structures where possible.

[0005] In consideration of the above points, the present invention aims to provide a highly functional protective fence in a type of fence in which a blocking surface is spanned between a support post and an anchor installed on the mountain side of the support post, while avoiding the use of extremely special configurations. [Means for solving the problem]

[0006] (Configuration 1) A protective fence to be installed on a slope, comprising: a number of posts; anchors installed on the mountain side of the posts; the tops of the posts and a panel material stretched between the anchors, the panel material comprising a wire mesh having a roughly rectangular outer shape; and one panel material cord passed around three sides of the wire mesh including at least one side of the wire mesh that is installed at the top of the posts; and an upper side rope that is installed on the top of the posts and fastened to the panel material, the upper side rope being arranged in a ring shape so as to go back and forth between adjacent posts, with the panel material fastened to one of the two sides.

[0007] (Configuration 2) A protective fence as described in configuration 1, wherein a portion of the panel material cord is looped, and the looped portion forms an attachment portion for the upper portion of the support.

[0008] (Configuration 3) A protective fence as described in configuration 1 or 2, wherein the panel material comprises a second panel material cord that is passed through one side other than the three peripheral sides of the wire mesh, and a third panel material cord that is stretched between the panel material cord and the second panel material cord or between the panel material cords and passes through the wire mesh.

[0009] (Configuration 4) A construction method for a protective fence comprising a plurality of posts, anchors installed on the mountain side of the posts, and a panel stretched between the upper parts of the posts and the anchors, the construction method for a protective fence comprising the steps of: erecting the posts on a slope; installing the anchors on the mountain side of the posts; and spanning the formed panel between the upper parts of the posts and the anchors, the construction method for a protective fence comprising the steps of: passing one panel material cord around three peripheral sides of a wire mesh having a substantially rectangular outer shape that fits the span between the posts, the wire mesh including at least one side that is located on the upper part of the posts, with a single panel material cord; passing a second panel material cord around the remaining side of the wire mesh; and passing a plurality of third panel material cords through the wire mesh, thereby stretching a plurality of the third panel material cords between opposite sides of the wire mesh.

[0010] (Configuration 5) A construction method for a protective fence as described in configuration 4, comprising a step of fastening the panel to an upper edge rope having a length at least twice the distance between adjacent posts, and forming the upper edge rope into a ring so that it travels back and forth around the post and is installed on the top of the post.

[0011] (Configuration 6) A method for constructing a protective fence as described in configuration 4 or 5, comprising a step of forming an attachment portion for the upper part of the support by looping a portion of the panel material cord when passing the panel material cord through the wire mesh.

[0012] (Configuration 7) A method for constructing a protective fence as described in any one of configurations 4 to 6, in which the eye processing at one end of the panel cord is formed by aluminum lock processing in a factory, and the eye processing at the other end is formed at the installation site using a cord fastener having a wedge member after the cord has been passed through three sides of the wire mesh. Effect of the Invention

[0013] According to the present invention, in a protective fence in which a blocking surface is spanned between a support post and an anchor installed on the mountain side of the support post, it is possible to provide a highly functional protective fence while avoiding the use of extremely special configurations. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a side view showing a protective fence according to an embodiment of the present invention; [Diagram 2] FIG. 1 is a front view showing a protective fence according to an embodiment; [Diagram 3] FIG. 1 is a top view showing a protective fence according to an embodiment; [Figure 4] FIG. 1 shows a face material of a protective fence according to an embodiment. [Diagram 5] Photographs showing the process of forming the face material of the embodiment [Figure 6] Photographs showing the process of forming the face material of the embodiment [Figure 7] Photograph showing a loading experiment of the protective fence of the embodiment [Figure 8] Photograph showing the loading experiment [Figure 9] Photograph showing a collision test of the protective fence according to the embodiment DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that the following embodiment is one form for realizing the present invention, and is not intended to limit the scope of the present invention.

[0016] 1 to 3 are diagrams showing the configuration of a protective fence according to an embodiment of the present invention, with FIG. 1 being a side view, FIG. 2 being a front view (viewed from the valley side), and FIG. 3 being a top view, respectively. The protective fence 1 of this embodiment is a protective fence installed on sloping ground, with a blocking surface having a flexible structure that is spanned between a support post and an anchor installed on the mountain side of the post, making it capable of dealing with both falling rocks and avalanches.

[0017] As shown in FIGS. 1 to 3, the protective fence 1 includes: A plurality of supports 12; A mountain side anchor 13 is provided on the mountain side (upward of the slope) of the support 12; A valley side anchor 14 is provided on the valley side (downward of the slope) of the support pillar 12; A surface material 11 stretched between the upper part of the support 12 and the mountain side anchor 13; At the top of the support 12, an upper side rope (upper side rope body) 15 is stretched between the support pillars and suspends the face material 11; A lower side rope (lower side rope body) 16 is stretched between adjacent mountain side anchors 13 and holds the lower side of the face material 11; Each of the stay ropes stretched between each of the above members; It is equipped with:

[0018] In this embodiment, the support pillar 12 is made of a steel pipe, and is provided with a base plate at its bottom (a steel plate is welded to the steel pipe). The support pillar 12 is installed on a concrete block formed on a slope. A protrusion (rod-shaped member) is provided on the bottom surface of the base plate, and the support pillar 12 is erected by inserting the protrusion into a hole formed in the concrete block. The pillars 12 are not directly fixed to the concrete blocks, but rather the installation position and posture of the pillars 12 are maintained by connecting them to the respective stay ropes described below. The support 12 is provided with mounting members (121, 122, 123, 124) for fastening a stay rope or the like. The mounting members include, for example, mounting pieces 121, 122, 123 welded to the support and a pin member (pin bolt) 124. When a mounting metal fitting such as a shackle is attached to the mounting hole of the mounting pieces 121, 122, 123 or when a rope with an eye at the end is passed through the support, it is locked by the pin member 124. In this embodiment, the support 12 is formed of a steel pipe, but the present invention is not limited to this, and any member that can be used as a support (such as an H-shaped steel) may be used. Similarly, the configuration for attaching the stay ropes and the like is not limited to the illustrated attachment members (121, 122, 123, 124), and any structure or mechanism that is used for attaching a rope or the like may be used.

[0019] The mountain side anchor 13 and the valley side anchor 14 have connection parts on their head sides, and are driven into the slope and connected to the respective stay ropes, etc., to hold (fix) the respective components. Various types of anchors can be used for the mountain side anchor 13 and the valley side anchor 14, and an appropriate one can be selected depending on the condition of the strata where they are driven and the required strength, etc. Similarly, any conventionally used attachment materials and methods can be used for the materials and methods for attaching the respective components to the anchors.

[0020] The upper side rope (upper side rope body) 15 is arranged between the adjacent supports 12 so as to wrap around the two supports (therefore, it has a length at least twice the distance between the adjacent supports). Specifically, a wire rope having an eye 151 at one end formed by aluminum lock processing (for example, Toyolock processing (registered trademark)) in a factory is used (see FIG. 4), and an eye is formed at the other end 152 using a wire grip and a thimble so that the wire length is appropriate according to the distance between the supports, and the wire rope is arranged in a ring shape so as to surround the upper parts of the two adjacent supports 12. The eyes at both ends of the wire rope are connected using turnbuckles 153, and the tension is adjusted by the turnbuckles 153. The upper side rope 15 is arranged at the upper part of the support 12 by being engaged with a pin bolt 124 formed at the upper part of the support 12 (see FIG. 1). As a result, the upper side rope 15 arranged on the upper part of the support is arranged in a loop (and can slide on the support) so as to go back and forth between the two support poles. As described above, by using a wire rope with an eye part at one end processed at a factory and processing the eye part at the other end on site, it is possible to adjust the dimensions on site and it is also excellent in work efficiency. The upper edge rope (upper edge cord) 15 is a member that is fastened to the panel to hold (reinforce) the upper edge side of the panel 11, and is fastened to the panel 11 in advance (before attaching to the support) for one of the two directions (note that it may also be fastened to the panel 11 after the upper edge rope 15 is attached to the support). As will be described later, the above configuration makes it possible to more effectively obtain a load distribution function in a configuration in which a panel 11 is suspended by a single panel rope arranged on three sides around the wire mesh. In addition, for on-site processing of the eye portion at the other end, a rope fastener having a wedge member such as Simple Lock (registered trademark) (described below) may be used.

[0021] The lower side rope (lower side rope body) 16 has both ends connected to the mountain side anchors 13 (through connecting members such as shackles, etc.) and is fastened to the lower side of the face material 11 to hold (reinforce) the lower side of the face material 11. For the lower side rope 16 in this embodiment, a wire rope with the same specifications as the upper side rope 15 is used. In this embodiment, a wire rope with eye portions pre-formed on both ends is used, but a similar concept to that of the upper side rope 15 may also be applied to the lower side rope 16 (arranged in a ring shape and the face material 11 fastened to only one of the reciprocating ends).

[0022] The panel 11 that constitutes the blocking surface has a very simplified structure in which a single wire rope is continuously inserted through the upper left and right ends of a high-strength wire mesh made of high-tensile wire with a tensile strength of 1400 MPa or more. As shown in FIG. 4, the face material 11 is A wire mesh 111 having a substantially rectangular outer shape (a shape and size corresponding to the span between adjacent posts 12, and not necessarily limited to a strict rectangle (each corner is 90°)), A single sheet material rope (sheet material cord) 112 is passed through the meshes of the wire mesh on three sides (in this embodiment, the top side and both sides) of the wire mesh 111, including at least the top side of the wire mesh 111 (the side arranged on the top of the support 12); At the lower side of the wire mesh 111, a second panel rope (second panel rope body) 113 is passed through the mesh of the wire mesh; A plurality of third panel ropes (third panel ropes) 114 stretched between the panel rope 112 (upper side) and the second panel rope 113 (lower side) through the meshes of a wire mesh; It is equipped with:

[0023] When arranging each rope on the wire mesh 111, first, a plurality of third panel ropes 114 are arranged through the meshes of the wire mesh (a photograph of this state is shown in FIG. 5(a)). The third panel rope 114 is a reinforcing rope stretched between the upper side of the panel rope 112 and the second panel rope 113, and multiple third panel ropes 114 are provided. The third panel rope 114 of this embodiment is configured by bundling two wire ropes that are folded back in the middle, and an eye portion 1141 is formed at the folded back portion. The eye portion 1141 is positioned on the upper side, and the face material rope 112 is passed through this eye portion 1141, thereby forming a configuration in which the face material rope 112 and the eye portion 1141 are slidably engaged with each other. The engagement of the lower end of the third panel rope 114 with the second panel rope 113 is attached using an irregular (special) cross clip 1142 as shown in Fig. 4, so that the lower end of the third panel rope 114 can slide against the second panel rope 113 for a certain distance with a specified frictional force, and after sliding the certain distance, the end of the third panel rope 114 abuts against the irregular (special) cross clip and is attached so as not to slide any further. This provides the function of absorbing impact energy from falling rocks, etc.

[0024] Next, the facing rope 112 is placed. The face material rope 112 is made of a wire rope having an eye 1121 at one end formed by aluminum lock processing (for example, Toyolock processing (registered trademark)) at a factory, and the end 1122 at the other end where the eye 1121 is not formed is passed through the meshes of the wire mesh, so that the face material rope 112 is arranged on three sides (the top side and both sides) of the wire mesh 111. As described above, the eye 1141 of the third face material rope 114 is passed through the top side (a photograph of this process is shown in Figure 5 (b)). When the face material rope 112 is passed through the meshes of the wire mesh and arranged on each side of the wire mesh 111, the face material rope 112 is looped around the corners of the wire mesh 111 (corners of the roughly rectangular external shape) at the positions that will be the upper parts of the posts 12 (corners at both ends of the upper side) as shown in Fig. 5(c), thereby forming attachment parts 112L for the posts 12. At the positions where the face material ropes 112 cross each other when looped around, the face material ropes 112 are fastened to each other using cross clips 1122. This stabilizes the loop shape, improves workability, and provides a cushioning function by sliding with frictional force when colliding with falling rocks, etc. (Note that the cross clips 1122 are not essential). After the face material rope 112 is passed through the three sides of the wire mesh 111, the length of the rope is appropriately adjusted, and an eye 1123 is formed at the other end 1122, which is the tip side of the rope passed through the wire mesh, using a rope fastener SL (and a thimble) having a wedge member (see FIG. 6(a)). As the "rope fastener having a wedge member", a wedge clamp (specific product name is "Simple Lock (registered trademark)") disclosed in Japanese Patent No. 6009611 and Japanese Patent No. 6342563 can be used. Note that these wedge clamps are very excellent in terms of workability and are preferable, but the eye may be formed by any method, such as using a wire grip and a thimble. In this way, by using a wire rope with an eye at one end processed at a factory and processing the eye at the other end on site, it is possible to adjust the dimensions on site and the work efficiency is also excellent. The panel rope 112 is arranged through three sides, both sides and the top side, of the wire mesh 111, with both ends having eye portions disposed at both ends of the bottom side of the panel, and these eye portions are each connected to the mountain side anchors 13 (e.g. via connecting members such as shackles). In addition, the mounting portion 112L is passed through the top of the support 12 and held in place by being hooked onto a mounting member (pin bolt) 124 formed on the top of the support 12, thereby attaching the upper edge side of the panel 11 to the top of the support 12.

[0025] Next, the second panel rope 113 is placed. The second panel rope 113, like the panel rope 112, is made of a wire rope having an eye at one end formed by aluminum lock processing in a factory, and the other end where the eye is not formed is passed through the meshes of the wire mesh, so that it is arranged at the bottom side of the wire mesh 111. Also like the panel rope 112, an eye is formed at the other end, which is the tip side of the rope that has passed through the wire mesh. The second panel rope 113 in this embodiment is made of a wire rope with the same specifications as the panel rope 112. The second panel rope 113 is fastened to the third panel rope 114 using the irregular (special) cross clip 1142 as described above (see FIG. 6(a)). The second panel rope 113 may be placed prior to the placement of the third panel rope 114 and panel rope 112. The second panel rope 113 also has both ends, each having an eye portion, which are connected to the mountain side anchors 13 (through a connecting member such as a shackle, for example).

[0026] In this embodiment, the upper side rope 15 and the lower side rope 16 are attached to the panel 11 in advance (before the panel 11 is attached to the support 12). In this embodiment, the upper side rope 15 is fastened to the panel 11 by fastening the upper side rope 15 to the panel rope 112 using a plurality of wire grips WG (see Figures 4 and 6(b)). In addition, in this embodiment, the lower side rope 16 is fastened to the panel 11 by fastening the lower side rope 16 to the second panel rope 113 using multiple wire grips WG (see Figures 4 and 6(c)). In addition, the attachment of the panel 11 to the upper side rope 15 and the lower side rope 16 may be performed after (or at the same time as) the attachment of the panel 11 to the support 12.

[0027] In the protective fence 1 of this embodiment, the panel 11 (and upper side rope 15 and lower side rope 16) configured as described above is provided in one span between each of the posts 12. In this case, as gaps will form between adjacent panel materials 11 if left as is, wire mesh 17 (see FIG. 3) is provided as a panel material to cover these gaps. The wire mesh 17 is an auxiliary wire mesh that is provided between adjacent panel panels 11, with at least a portion of it overlapping both of the adjacent panel panels 11. The wire mesh 17 is attached to the face material 11 using an attachment member such as a fastening coil.

[0028] The respective stay ropes etc. are used to connect and secure the respective components described above, and in this embodiment, the following stay ropes are provided. Stay ropes SW1 connect the tops of the posts 12 at both ends to anchors (not shown) driven into the slope on both sides of the protective fence 1. Stay ropes SW5 connect the lower parts of the posts 12 at both ends to anchors (not shown) driven into the slope on both sides of the protective fence 1. A stay rope SW2 connects the top of each support 12 to the valley side anchor 14. A stay rope SW3 connects the lower part of each support 12 to the valley side anchor 14. A stay rope SW4 connects the lower part of each support 12. A stay rope SW6 connects the bottom of each support pillar 12 to the mountain side anchor 13. Furthermore, a shape-retaining rope SW7 is provided to maintain the overall shape of the protective fence 1. The shape-retaining rope SW7 connects the center of both sides of the face material rope 112 to the lower part of the support pole 12, and is provided so as to pull and taut the face material rope 112 as shown in Fig. 1 (thereby urging the upper part of the support pole 12 toward the mountain side). In addition, the structure for connecting each rope to each component can be any structure (structure that can obtain the required strength) used for fastening each component such as a rope body, such as appropriately using connecting members such as shackles or ring members. In addition, while the present embodiment uses as an example a structure equipped with the above-mentioned backing ropes, etc., the present invention is not limited to this, and the number of backing ropes (and anchors, etc. required to secure them) may be increased or decreased, or the positions at which they are installed may be changed, in order to obtain the required fixing strength for each component.

[0029] The construction method of the protective fence 1 described above is as follows: A step of erecting a support 12 on a slope; a step of providing a mountain side anchor 13 on the mountain side of the support 12; Providing a valley side anchor 14 on the valley side of the support pillar 12; A step of bridging the formed panel 11 between the top of the support 12 and the mountain side anchor 13; Stretching each of the stay ropes between each of the members; has. More specifically, the following operations are carried out. As will be understood from the above description, the face material 11 is formed as follows: A step of cutting the continuously formed wire mesh delivered to the installation site to an appropriate size according to the interval between the posts 12, etc., to form a wire mesh 111 having a substantially rectangular outer shape; A step of stretching a plurality of third panel ropes 114 between opposite sides of the wire mesh 111 by passing the plurality of third panel ropes 114 through the wire mesh 111; A step of passing the face material rope 112 around three sides of the wire mesh 111 (at this time, the loop-shaped attachment portion 112L is also formed); A step of passing a second panel rope 113 through the remaining side of the wire mesh 111; a step of engaging the upper end of the third panel rope 114 with the panel rope 112 (as described above, in this embodiment, this is performed at the same time as passing the panel rope 112 through the wire mesh 111); Engaging the lower end of the third panel rope 114 with the second panel rope 113; The wire mesh may be cut to an appropriate size in accordance with the interval between the posts 12, etc. in a factory, and the cut wire mesh may be delivered to the installation site. The work of attaching the formed panel 11 to the top of the support 12 includes the steps of hanging the attachment portion 112L from the top of the support 12, and arranging the upper edge rope 15 in a loop so that it goes back and forth around the tops of the two support pillars 12 (so that, on one of the two occasions, the panel 11 with the upper edge (panel rope 112) fastened thereto is held to the support 12 via the upper edge rope 15). In addition, the work of attaching the formed panel 11 to the mountain side anchors 13 includes the steps of connecting both ends of the panel rope 112 to the mountain side anchors 13, connecting both ends of the second panel rope 113 to the mountain side anchors 13, and connecting both ends of the lower edge rope 16 fastened to the lower edge of the panel 11 (the second panel rope 113) to the mountain side anchors 13.

[0030] In the protective fence 1 of this embodiment, the face material 11, which is one of the main components of the protective fence, has a simplified structure made of wire rope and wire mesh, and provides good workability in on-site assembly. The simplified structure makes it possible to reduce the weight and number of parts, which is useful in all aspects of on-site (slope) work, from transporting the components to assembly. Furthermore, according to the protective fence 1 of this embodiment, the surface material rope 112 arranged continuously around three sides, including the upper side, of the surface material 11 can transmit the impact energy of a falling rock, thereby providing a high load distribution function at the upper part, etc. (providing a highly functional protective fence). In addition, since the panel rope 112 is configured to be fastened to one side of the upper side rope 15 which is arranged in a ring shape on the support 12, the workability of constructing the protective fence can be improved while maintaining a high load distribution function. In order to provide the protective fence with the ability to capture falling rocks, etc., the upper part of the face material 11 needs to have a certain strength, and for this, the wire rope arranged on the upper part of the face material 11 needs to have a certain thickness. However, if the wire rope becomes too thick, the workability of passing it through the mesh of the wire mesh of the face material 11 decreases significantly (or it cannot be passed through the mesh at all). Therefore, by using face material rope 112 that passes through the wire mesh of the face material 11 and upper side rope 15 (a rope thicker than the face material rope 112) that reinforces this, both workability and strength are achieved. Furthermore, if the panel 11, which has one panel rope 112 arranged on three sides of the periphery of the wire mesh, is simply fastened to a reinforcing rope stretched between the posts, the load distribution function may be reduced. In the panel 11 configured as described above, the length and position of the upper side of the panel rope 112 are relatively flexible (this improves the load distribution function), and if this is simply fastened to the reinforcing rope stretched between the posts, the load may be biased to either the panel rope 112 or the reinforcing rope. In contrast, according to the protective fence 1 of this embodiment, the panel rope 112 is fastened to one side of the upper side rope 15 that is provided in a ring shape around the post 12, so that flexibility is created on the upper side rope 15 side as well, and therefore the load distribution function can be maintained at a high level.

[0031] In the protective fence 1 of this embodiment, the upper side rope 15 and the face material rope 112 use wire ropes with the eye portion at one end processed at a factory and the eye portion at the other end processed on site, which makes it easy to adjust on site and also improves work efficiency. It should be noted that the present invention is not limited to this, and the eye portions at both ends may be machined on-site (however, this embodiment provides better work efficiency).

[0032] According to the protective fence 1 of this embodiment, the panel rope 112 is looped at the corner of the wire mesh to form an attachment portion 112L for the upper part of the post, so that no additional attachment parts are required, making it possible to reduce the weight and the number of parts. In this embodiment, the face material ropes 112 are provided on three sides of the wire mesh, but they may be provided around the entire circumference of the wire mesh, with the face material ropes arranged in a ring shape along the outer periphery of the wire mesh, and the face material ropes may be looped at all corners to form attachments at each corner. Also, the locations where the loops are formed are not limited to the corners of the wire mesh, and they may be formed in the middle of each side. Incidentally, forming the attachment portion by looping the panel rope 112 is not essential to the present invention, and a separate attachment member or the like may be used (however, in this case a separate attachment member or the like is required, and therefore the present embodiment is more preferable). In addition, in this embodiment, the face material ropes 112 are arranged on the top and both side edges of the wire mesh as an example, but the present invention is not limited to this, and it is sufficient that the face material ropes 112 are arranged on "the three peripheral sides of the wire mesh, including at least one side arranged on the top of the support."

[0033] In this embodiment, an example is shown in which there are four pillars 12 (three spans), but the present invention is not limited to this, and the number of spans can of course be any number (as long as there are two or more pillars).

[0034] <Load test> Next, a loading test (strength test as an avalanche prevention fence) performed on the protective fence described in the embodiment will be described. 1. Experimental Conditions It would be ideal to verify the structure of an avalanche prevention fence using actual snow pressure, but since snow pressure is easily affected by snowfall and temperature fluctuations, there is a high possibility that the result will be unstable snow conditions. Therefore, in this verification, we prioritized collecting quantitative data, and conducted static load tests using large sandbags filled with soil. The test conditions are shown below. Test specimen The test specimen was a guard fence with a post height of 3.43 m, a post interval of 4.5 m, and three spans, as explained in the embodiment, which had been determined in advance through provisional calculations performed on a desk. For the anchors, metal fittings were attached to the temporary materials on the experimental stand to substitute for the fixed parts. For the base of the post, it was assumed that it would actually be the natural ground, and a base structure was made using hard rubber to give the post flexibility in terms of sinking and rotation. ·Pseudo slope A simulated slope was created on the impact test stand using temporary materials, single pipes, scaffolding boards, and plywood. Figure 7 shows the state in which the test specimen was installed on the test stand. ·Delivery load Snow depth 3.0m, slope gradient 45 degrees, snow density 3.5kN / m 3 The total load per three spans was calculated taking into account a creep coefficient of 0.795, a glide coefficient of 3.6, and a snow accumulation coefficient of 1.0, and converted into the weight and quantity of one large sandbag filled with soil. ·Loading method The large sandbags were lifted one by one by a crane, and after measuring the mass of the sandbags using a crane scale, they were gently lowered into the designated position on the blocking surface. At that time, the loading was continued while taking care to distribute the load as evenly as possible across the three spans (the loading state is shown in Fig. 8).

[0035] 4. Load test results When sandbags with a load equivalent to a snow depth of 3.0 m were placed on a protective fence in an embodiment designed for a snow depth of 3.0 m, the fence maintained the load without breaking.

[0036] <Collision experiment> Next, a collision test (strength test as a rockfall protection fence) performed on the protection fence described in the embodiment will be described. 1. Experimental Conditions A 45-degree inclined platform was made from steel members and the test specimen was attached to it. The core of the weight was aligned with the target drop position on the blocking surface using a crane and hoisted up to the specified height. The height was measured using a total station from the blocking surface to a height of 34.0 m, after which the weight was dropped using an air-type release device to collide with the test specimen. The speed was measured by reading the target mark on the weight with a high-speed camera. The rope tension was measured with a rod equipped with a strain gauge, and the collision displacement of the test specimen was filmed with a high-speed camera and a video camera. The experimental conditions are shown in Figures 9(a) and (b). Experimental method: Free fall method Weight shape / material / weight: W=0.33t (SAEFL type, made of polyhedral concrete) Weight drop height: 32.0m or more Weight speed: 25.0m / sec or more Weight incidence angle: 90° Collision energy: 100kJ or more Collision location: 2 / 3 from the bottom, center of each span, projected from the top

[0037] ·Specimen The basic structure is based on the structure used in the load test, but the support span was changed from 4.5 m to 3.0 m, assuming that the support span would be narrowed by the snow load condition. The specifications are shown in Table 4.

[0038] [Table 1]

[0039] 4. Collision test results The test specimen, which was designed to withstand 100kJ, had the ability to capture 116kJ of weight impact energy in both the center span and end span in an experiment based on the Rockfall Countermeasures Handbook. For the center span, even after continuous impacts without repairs, the blocking surface deformed but the entire structure remained stable and the remaining height was adequately maintained. [Explanation of symbols]

[0040] 1...protective fence 11...Surface material 111...Wire mesh 112...Surface material rope (surface material rope body) 112L...Attachment part (loop part) 113...Second panel rope (second panel rope) 114...Third panel rope (third panel rope) 12...post 13...Mountain side anchor (anchor installed on the mountain side of the support pillar) 15...Upper side rope (upper side rope body)

Claims

1. A protective fence installed on a slope, Several pillars and An anchor provided on the mountain side of the support pillar; A surface material stretched between the upper part of the support and the anchor, A wire mesh having a substantially rectangular outer shape; A panel material including a panel material cord passing through three sides of the wire mesh including one side disposed on the upper part of the support pillar of the wire mesh and both sides; A rope body is arranged on the upper part of the support and fastened to the face material, the rope body being provided in a ring shape so as to travel back and forth between adjacent support columns, and the face material is fastened to one of the travels; and Equipped with A protective fence in which a portion of the middle part of the panel material cord is looped, and the looped part forms an attachment part for the upper part of the support.

2. A protective fence as described in claim 1, wherein the upper edge rope body, which is annular, and the loop-shaped portion of the surface material rope body are arranged to pass from the top of the support and are engaged by being hooked onto an attachment member formed on the upper part of the support.

3. The face material is A second panel cord that is passed through a lower side of the wire mesh and has both ends connected to the anchor via a connecting member; A protective fence as described in claim 1 or 2, comprising a third panel material rope, a rope stretched between the panel material rope and the second panel material rope through the wire mesh, wherein an eye portion through which the panel material rope is passed is formed by folding back one rope in the middle, and two ropes extending from the eye portion are passed through the wire mesh and connected to the second panel material rope.

4. A protective fence as described in claim 3, comprising a lower edge rope body fastened to the panel, both ends of which are connected to the anchors via connecting members.

5. A construction method for a protective fence including a plurality of posts, anchors provided on the mountain side of the posts, and a surface material stretched between an upper portion of the posts and the anchors, comprising: A step of erecting the support on a slope; Providing the anchor on a mountain side of the support pillar; A step of bridging the formed panel between an upper portion of the support and the anchor; having In forming the face material, A step of passing a single surface material cord around three sides of the wire mesh, including one side and both sides arranged on the upper part of the support posts, of the wire mesh having a substantially rectangular outer shape that fits the span between the support posts; When passing the panel material cord through the wire mesh, a part of the middle part of the panel material cord is looped around to form an attachment part for an upper part of the support pole; Passing a second panel member through a lower side of the wire mesh; A step of stretching a plurality of third panel material cords between opposite sides of the wire mesh by passing the third panel material cords through the wire mesh; A method for constructing a protective fence comprising the steps of:

6. Before the step of laying the panel, a step of fastening the panel to an upper side rope having a length at least twice the distance between the adjacent columns; 6. A method for constructing a protective fence as described in claim 5, further comprising a step of forming the upper side rope into a ring and attaching it to the upper part of the support by making it go back and forth between the support and the upper side rope.

7. 7. A method for constructing a protective fence as described in claim 5 or 6, comprising a step of passing the loop-shaped portion of the panel material rope from above the support and hooking it onto an attachment member formed on the upper part of the support.

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