Bamboo fall prevention structure

Abstract

To provide a bamboo-falling prevention structure that can effectively prevent the highly uncertain falling of bamboo by a simple method. [Solution] The system comprises a plurality of support posts 10 set up at intervals, a plurality of barrier ropes 20 laid horizontally at intervals in the vertical direction between the heads of adjacent pairs of support posts 10, buffer devices 25 installed near both ends of the barrier ropes, and cross ropes 30 stretched across the upper and lower parts of adjacent pairs of support posts 10, and the sliding resistance of the plurality of barrier ropes 20 prevents the bamboo from tipping over.

Description

[Technical Field]

[0001] The present invention relates to a bamboo fall prevention structure that prevents bamboo groves from falling due to snow loads or the like. [Background technology]

[0002] In areas where bamboo stands near roads, railways, or other routes, if the bamboo falls onto the roads due to the weight of snow in winter, it not only obstructs the passage of vehicles and trains, but can also cause traffic accidents.

[0003] One way to avoid this type of damage from fallen bamboo is to cut it down in advance. Pre-cutting involves workers regularly inspecting bamboo groves adjacent to roads and railway tracks and cutting down any bamboo that is expected to fall.

[0004] On the other hand, a tree fall prevention device that combines multiple sets of anchors and stay ropes is widely known as a means for preventing trees from falling (Patent Documents 1 and 2). This type of tree fall prevention device connects an anchor fixed around a standing tree to the trunk of the standing tree with a stay rope, and prevents the tree from tipping over through the stay rope while receiving a reaction force from the anchor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 57-84864 (Figure 1) [Patent Document 2] Japanese Patent Application Publication No. 9-327241 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventional techniques for avoiding damage caused by fallen bamboo involve the following issues that need to be resolved: <1> No effective technique for preventing bamboo from falling has yet been proposed that can reliably control the falling of bamboo. <2> Therefore, the problem is being addressed by cutting down only the necessary areas, but this method of cutting down bamboo by hand requires a great deal of time and effort for the cutting work and post-cutting process, in addition to regular monitoring, resulting in enormous costs for dealing with fallen trees. <3> Because the vegetation patterns of standing trees and bamboo forests differ in many ways, it is difficult to directly apply tree fall prevention techniques to bamboo fall prevention. For example, in the case of a bamboo forest where bamboo grows in clusters, it is uncertain whether a single bamboo will fall or whether multiple bamboo will fall at once, making it difficult to identify the target of the fall. If an attempt were made to apply tree-felling techniques to such bamboo, which require multiple sets of bracing ropes and anchors per standing tree, the same number of bracing ropes and anchors would be required as there were bamboos. This would not only require a great deal of time and effort to install the anchors and bracing ropes, but would also result in enormous installation costs, making it unfeasible.

[0007] The present invention has been made in consideration of the above points, and its purpose is to propose the following fallen bamboo prevention structure. <1> To effectively prevent the highly uncertain tilting of bamboo using a simple method. <2> To achieve both a reduction in the cost of preventing fallen bamboo and an improvement in the performance of preventing fallen bamboo. <3> To avoid tilting of the support and damage to the support. <4> The bamboo's tilting force can be distributed throughout the structure, providing efficient support. [Means for solving the problem]

[0008] The present invention provides A gate-shaped bamboo fall prevention structure erected along the boundary between the bamboo grove and the road prevents bamboo facing the road from freely falling toward the road. Standing at intervals , and has a length that can support the tilting of the bamboo Multiple supports and adjacent pairs of supports with a gap in the height direction between the heads In multiple stages Crossing , supporting the bamboo leaning towards the line A plurality of barrier cords and a barrier cord are installed near both ends of the plurality of barrier cords, and when a tension of a certain level or more is applied to the plurality of barrier cords, the barrier cords Allowing sliding of the barrier rope The barrier is provided with a buffer that attenuates tension and a cross rope stretched across the upper and lower parts of the pair of adjacent supports, and the ... The barrier ropes are laid horizontally in multiple stages, one after the other, from the upper barrier rope to the lower barrier rope. Bamboo Free Prevents inclination. In another embodiment of the present invention, the entire length of the barrier cord is longer than the span length of the support pole, and an excess length portion is formed at the portion where the barrier cord extends from the buffer. In another embodiment of the present invention, both ends of the plurality of barrier cords may be attached by passing through the heads of the pair of adjacent posts. In another embodiment of the present invention, both ends of the plurality of barrier cords may be attached to shock absorbers attached to the outsides of the heads of the pair of adjacent posts. In another embodiment of the present invention, the buffer is a friction sliding type buffer that allows the barrier rope to slide. In another embodiment of the present invention, a tension adjuster capable of adjusting the erection angle of the support posts may be provided between the lower ends of the cross ropes and the lower portions of the pair of support posts. [Effects of the Invention]

[0009] The present invention has at least one of the following advantages. <1> A simple gate-shaped structure with multiple barrier ropes with shock absorbers hung horizontally between the heads of multiple supports can effectively prevent the bamboo from tipping over, which is highly uncertain. <2> It is possible to provide a highly effective bamboo fall prevention structure that can reliably prevent bamboo from falling without relying on manual bamboo felling work or difficult-to-apply tree fall prevention technology. Therefore, it is possible to achieve both a reduction in the cost of preventing fallen bamboo and an improvement in the performance of preventing fallen bamboo. <3> By combining the buffer attached to the barrier rope with the cross rope, it is possible to avoid breakage of the barrier rope and damage to the support pole. <4> The load transmission performance between each span is improved through the barrier cables stretched between adjacent pairs of pillars. Therefore, the bamboo tilting force acting on one part of the bamboo-falling prevention structure can be distributed throughout the entire bamboo-falling prevention structure and efficiently supported. <5> By providing a tension adjuster between the lower end of the cross rope and the lower part of the support, not only can the cross rope be tensioned without slack, but also the tension length of the cross rope can be adjusted by the tension adjuster during the work of erecting the support, thereby adjusting the erection angle of the support. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a bamboo fall prevention structure according to the present invention, with a portion omitted. [Figure 2A] Perspective view of the head of the support [Figure 2B] Perspective view of the lower part of the support [Figure 3] A perspective view of the head of the support pole to which the barrier cord is fixed via a buffer. [Figure 4] An explanatory diagram of the shock absorber. (A) is an exploded view of the shock absorber, and (B) is a perspective view of the entire shock absorber. [Figure 5A] Illustration of the upper barrier rope's effect in preventing bamboo from falling [Figure 5B] Illustration of the upper and lower barrier ropes preventing bamboo from falling [Figure 6] Illustration of the shape-maintaining effect of cross ropes DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below with reference to the drawings.

[0012] <1> Overview of the bamboo fall prevention structure The description will be made with reference to FIGS. As shown in Figure 1, the bamboo-falling prevention structure of the present invention comprises a plurality of posts 10 erected at a predetermined interval, a plurality of barrier ropes 20 horizontally strung in multiple stages at intervals between the heads of adjacent pairs of posts 10, buffer devices 25 provided at both ends of each barrier rope 20, and cross ropes 30 stretched across the upper and lower parts of adjacent pairs of posts 10. The bamboo fall prevention structure can be erected, for example, along the boundary between a bamboo grove and a road, railway, or other route, and the sliding resistance of the multiple barrier ropes 20 can effectively prevent bamboo from falling. Each component will be explained in detail below.

[0013] <2> pillar The posts 10 are rigid members for supporting a plurality of barrier cords 20, and are erected at predetermined intervals. The support pole 10 may be erected, for example, by burying the support pole body in the ground or in a concrete foundation, or by fixing a base plate integrally provided at the bottom of the support pole 10 with an anchor or the like.

[0014] <2.1> Total length of support The overall length of the support 10 has an appropriate dimension to be able to support the leaning bamboo. The support 10 may be a single pillar or may be made up of a combination of multiple segments.

[0015] <2.2> Support material The support pillar 10 may be made of a material such as a steel pillar, a concrete pillar, or a wooden pillar.

[0016] <2.3> Back rope As shown in FIG. 1, if necessary, a back stay rope 41 is connected between the back anchor 40 provided on the back side (bamboo forest side) of each support 10 and the support 10. Similarly, a lateral support rope 43 is connected between a lateral anchor 42 provided on the side of the terminal support 10 (in the extension direction of the bamboo-falling prevention structure) and the terminal support 10. These stay ropes 41, 43 may be provided with shock absorbers or may not require the provision of shock absorbers.

[0017] <3> Barrier rope Near the heads of the pair of support posts 10, two or more barrier ropes 20 are laid horizontally in multiple stages. The reason why multiple barrier ropes 20 are laid horizontally in multiple stages is so that the multiple barrier ropes 20 can work together to support the uneven tilting load of the bamboo.

[0018] The barrier rope 20 is a tension member that receives a reaction force from the support 10 to prevent the bamboo from tilting over, and can be made of a steel or resin cable material. Near the end of each barrier rope 20, a buffer 25 is slidably held via the buffer 25 anchored to the support 10. The structure for holding the end of each barrier cord 20 will be described later.

[0019] <3.1> Total length of the barrier cord The barrier ropes 20 are not installed across multiple spans of the support 10, but are installed for each span of the support 10.

[0020] <3.2>Extra length The total length of the barrier cord 20 is longer than the span length of the support 10, and excess length portions 21 of an appropriate length are formed at both ends of the cord where they extend from the buffer 25. The reason why the extra length portion 21 is formed at the end of the barrier cord 20 is to allow the barrier cord 20 to slide (slip) against the buffer 25 and to attenuate the tension acting on the barrier cord 20 . The sliding length of the barrier rope 20 is determined by the set dimension of the extra length portion 21 .

[0021] It is also possible to provide a stopper (not shown) at the end of each barrier cord 20 to prevent the end of the barrier cord 20 from slipping out of the buffer 25 .

[0022] <3.3> Barrier cable installation height The installation height of the barrier rope 20 is selected appropriately taking into consideration the height of the bamboo at the site so as to prevent the bamboo from tilting and causing traffic disruptions.

[0023] <3.4> Number of barrier cable installation layers In this example, a configuration will be described in which two barrier cords 20 (20a, 20b) are laid horizontally in multiple stages between a pair of posts 10, but the number of barrier cords 20 may be three or more.

[0024] <3.5> Barrier cable installation interval The intervals at which the barrier cords 20 are installed can be selected as appropriate. The practical installation interval of the barrier cords 20 is about 0.5 to 1.5 m.

[0025] <4> Buffer A buffer 25 is provided near the end of the barrier cord 20. The buffer 25 not only attenuates the tension acting on the barrier cord 20 but also helps prevent the barrier cord 20 from breaking.

[0026] <4.1> Examples of shock absorbers The buffer 25 illustrated in Figure 4 is equipped with, for example, two clamping plates 26, 26, and a tightening bolt 27 and nut 28 that can be tightened between the two clamping plates 26, 26.The barrier cable 20 is sandwiched between the two clamping plates 26, 26, and the structure is such that energy can be attenuated by frictional resistance between the contact surfaces of the clamping plates 26 and the barrier cable 20. The buffer 25 is not limited to the form illustrated in this example, and a known friction sliding type buffer can be applied.

[0027] <4.2> Barrier rope attachment structure The barrier cords 20 are slidably attached to the respective posts 10 via shock absorbers 25 . The mounting structure of the barrier ropes 20 shown in FIG. 2A will be described. Both ends of the barrier cord 20 can be inserted into the through-holes 11 formed in the head of the support 10, and the excess length 21 of the barrier cord 20 can be held and attached by the buffer 25. In this mounting configuration, one buffer 25 holds one barrier cord 20 .

[0028] Another mounting structure shown in FIG. 3 will be described. Mounting pieces 12 capable of anchoring shock absorbers 25 are provided laterally on the outer peripheral surface of the head of the support pole 10. The buffer 25 may be anchored in the anchoring hole 13 formed in the mounting piece 12, and the buffer 25 may grip and fix the barrier cord 20. In this mounting configuration, the barrier cords 20 are not inserted through the support pole 10, but are mounted by having two barrier cords 20 gripped by one buffer 25 mounted on the outside of the support pole 10.

[0029] <4.3> Reasons for providing buffers at the ends of the barrier ropes The buffers 25 are provided at the ends of the barrier cords 20 arranged in multiple stages in order to reduce the load on the support posts 10 and to prevent the barrier cords 20 from breaking.

[0030] <4.4> Sliding resistance of barrier rope The sliding resistance of the upper barrier rope 20a and the lower barrier rope 20b caused by the buffer 25 is not limited to the same combination, and may be different combinations. The barrier ropes 20 may be configured so that the sliding resistance thereof gradually increases from the upper side to the lower side. In other words, by setting the sliding resistance of the buffer device 25 installed on the lower barrier rope 20b to be greater than the sliding resistance of the buffer device 25 installed on the upper barrier rope 20a, it is possible to cope with a greater tilting force of the bamboo.

[0031] For example, by increasing the number of installed buffers 25, the sliding resistance of the lower barrier ropes 20b can be easily increased.

[0032] <5> Cross rope A cross rope 30 is stretched between the top and bottom of a pair of adjacent posts 10, crossing them in an X shape. The cross ropes 30 function to maintain the shape of the bamboo-falling prevention structure by preventing adjacent posts 10 from leaning toward each other (in the direction in which the multiple posts 10 are arranged) when the bamboo's tilting force acts on the barrier ropes 20.

[0033] When attaching the cross ropes 30, tension adjusters 31 such as turnbuckles are provided at the ends of the cross ropes 30 as shown in FIG. 2B. By providing the tension adjuster 31 between the lower part of the support 10 and the lower end of the cross rope 30, the tension of the cross rope 30 can be adjusted at a position close to the ground surface. By providing the tension adjuster 31, not only can the cross ropes 30 be tensioned without slack, but also the tension length of the cross ropes 30 can be adjusted by the tension adjuster 31 during erection work of the support 10, thereby adjusting the erection angle of the support 10.

[0034] [Prevention of bamboo from falling by bamboo-falling prevention structures] The bamboo-falling prevention effect of the bamboo-falling prevention structure will be described with reference to FIGS. 5A and 5B.

[0035] <1> Before the bamboo forest fell In this example, we will explain a form in which the aforementioned bamboo fall prevention structure of a predetermined height is erected at the boundary between the bamboo grove and the road. The installation site for the bamboo fall prevention structure is not limited to the boundary between the bamboo grove and the road, but can be installed at various sites where it is necessary to prevent the bamboo grove from falling excessively.

[0036] <2> When the bamboo forest falls When bamboo forests are affected by snow accumulation or other factors, they tend to lean in various directions. If the bamboo leans toward the track, the bamboo fall prevention structure will restrict the bamboo from falling freely by preventing the bamboo from falling as described below.

[0037] <2.1> Preventing bamboo from falling over by using upper barrier ropes When bamboos tilt toward the bamboo-falling prevention structure, one or more bamboos lean against the barrier rope 20a located above the bamboo-falling prevention structure. The leaning load (tilting force) of the bamboo acts as tension on the upper barrier rope 20a.

[0038] <2.1.1> When the bamboo tilting force is small When the tension acting on the upper barrier cord 20a does not exceed the gripping force of the buffer 25 on the barrier cord 20, no sliding occurs between the barrier cord 20a and the buffer 25. The erection length of the upper barrier rope 20a remains the same as before the bamboo tilting force was applied. The tilting force of the bamboo acting on the upper barrier rope 20a is ultimately supported by the strength of the support 10. Therefore, the upper barrier rope 20a and the support pole 10 that make up the bamboo fall prevention structure work together to prevent the bamboo from falling freely.

[0039] <2.1.2> When the tilting force of the bamboo increases (Fig. 5A) For example, when the snow load increases, the tension acting on the upper barrier rope 20a increases in proportion to the tilting force of the bamboo. When the tension of the barrier cords 20a exceeds the gripping force of the buffers 25 on the barrier cords 20a, sliding occurs between the upper barrier cord 20a and the pair of buffers 25. When the upper barrier rope 20a slides and the installed length increases, the upper barrier rope 20a is subjected to the leaning force of the bamboo and the central part of the upper barrier rope 20a is bent downward. When the barrier ropes 20a slide, the tension acting on the upper barrier rope 20a is attenuated by the sliding resistance of the two buffers 25.

[0040] <2.2> The effect of lower barrier ropes to prevent bamboo from falling over (Fig. 5B) As the upper barrier rope 20a is bent downward, the regulating position of the bamboo drops. As the downward bending deformation of the upper barrier rope 20a progresses, the bamboo also leans against the lower barrier rope 20b. The lower barrier rope 20b also exerts the same function of preventing bamboo from falling as the upper barrier rope 20a described above.

[0041] That is, when the bamboo leans against the lower barrier rope 20b, the action of preventing the bamboo from falling over by the upper barrier rope 20a and the action of preventing the bamboo from falling over by the lower barrier rope 20b proceed in parallel. The bamboo receives the sliding resistance of the two buffers 25 provided on the upper barrier rope 20a as well as the sliding resistance of the two buffers 25 provided on the lower barrier rope 20a. Specifically, a total of four buffers 25 provided on the upper and lower barrier ropes 20a, 20b function simultaneously, effectively preventing the bamboo grove from tipping over. The force that prevents the bamboo from falling over increases in proportion to the number of barrier ropes 20 that are installed.

[0042] <3> Design strength of the support pillars If the barrier cord 20 is not provided with a buffer 25, the tilting force of the bamboo acting on the barrier cord 20 is transmitted directly to the support 10, so the support 10 must be made with high strength.

[0043] In contrast, by installing a buffer 25 on the barrier rope 20, when tension above a certain level acts on the barrier rope 20, sliding occurs between the barrier rope 20 and the buffer 25, and the tension on the barrier rope 20 is attenuated. Therefore, even if an excessive tilting force acts on the barrier rope 20, the load borne by the support pillar 10 does not change, and it is possible to avoid excessive load acting on the support pillar 10. Therefore, there is no need to design the strength of the support 10 to be greater than necessary, and the strength of the support 10 can be reduced to be designed economically.

[0044] <4> Shape maintenance effect by cross rope Referring to FIG. 6, the shape-maintaining function of the bamboo-falling prevention structure by the cross ropes 30 will be described. For the purpose of explanation, the section where the bamboo is leaning is defined as the loaded section S1, and the section adjacent to the loaded section S1 is defined as the adjacent section S2.

[0045] As the bamboo tilts, a tilting force f acts on the pair of supports 10 located in the load section S1 in the direction in which they approach each other. The support pillars 10 erected in the load section S1 are connected to the cross ropes 30 provided in the adjacent section S2 and to the support pillars 10 erected in the adjacent section. Therefore, the inward tilting force f acting on the support 10 of the loaded section S1 is supported by the support 10 of the adjacent section S2 through the cross ropes 30 installed in the adjacent section S2. Therefore, the pair of support posts 10 located in the load section S1 can be reliably prevented from tilting in the approaching direction, and the gate-shaped shape of the bamboo-falling prevention structure can be maintained.

[0046] <5> Distributed load transmission effect by cross ropes As shown in FIG. 6, the tilting load of the bamboo acting on the loaded section S1 is distributed and supported by the support posts 10 erected in the adjacent sections through the cross ropes 30. Therefore, the load on the support 10 located in the loaded section S1 is further reduced. [Explanation of symbols]

[0047] 10... Prop 11. Through hole 12 Mounting piece 13. Mooring hole 20. Barrier cable 20a···Upper barrier 20b Lower barrier 21...Extra length 25...Holding plate 26...Holding plate 27 Fastening bolt 28 Nut 30 Cross Rope 40 Rear anchor 41 Rear support rope 42 Lateral anchor 43 Lateral brace S1... Load section S2: Adjacent section

Claims

1. A gate-shaped bamboo fall prevention structure erected along the boundary between a bamboo grove and a roadway to prevent bamboo facing the roadway from freely falling toward the roadway, A plurality of support poles are erected at intervals and have a total length sufficient to support the tilting of the bamboo; A plurality of barrier ropes are laid horizontally in multiple stages at intervals in the height direction between the heads of adjacent pairs of support posts, supporting bamboo that leans toward the track; a buffer device that is installed near both ends of the barrier ropes and that allows the barrier ropes to slide when tension equal to or greater than a certain level acts on the barrier ropes, thereby attenuating the tension of the barrier ropes; and cross ropes stretched across the upper and lower parts of the pair of adjacent columns, The sliding resistance of the multiple barrier ropes prevents the bamboo from tilting freely from the upper barrier ropes to the lower barrier ropes that are laid horizontally in multiple stages. Bamboo fall prevention structure.

2. 2. The bamboo-falling prevention structure according to claim 1, characterized in that the total length of the barrier rope is longer than the span length of the support pole, and an excess length is formed at the portion where the barrier rope extends from the buffer device.

3. The bamboo-falling prevention structure according to claim 1, characterized in that both ends of the plurality of barrier ropes are attached by passing through the heads of the pair of adjacent posts.

4. The bamboo-falling prevention structure according to claim 1, characterized in that both ends of the plurality of barrier ropes are attached to buffers attached to the outside of the heads of the pair of adjacent posts.

5. The bamboo-falling prevention structure according to claim 1, characterized in that the buffer is a friction sliding type buffer that allows the barrier rope to slide.

6. The bamboo-falling prevention structure according to claim 1, characterized in that a tension adjusting device capable of adjusting the erection angle of the support posts is provided between the lower end of the cross rope and the lower part of the pair of support posts.

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