JPS6124711A - Impact force absorbing apparatus for preventing snowfall or falling rock - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an impact force absorbing device for preventing avalanches and rockfalls, and particularly to shock absorbers attached to supporting wires of avalanche and rockfall prevention bodies such as prevention walls, nets, and fences. Regarding force absorption devices.

[Conventional technology and its problems]

Japanese Utility Model Publication No. 7378/1982 and Publication No. 6971/1987 propose that the avalanche/rockfall preventive body is simply suspended from supporting wires such as wires, but these methods do not allow impact to the preventive body. The damage rate is high because force is applied directly. For this reason, there is a need for foundations, wires, and the main material of the prevention body to be highly rigid and difficult to break. On the other hand, this type of prevention body is often installed in the middle of a mountain slope deep from the roadside. Because of this, there is a trend toward a reduction in material and weight reduction.

[Purpose of the invention]

An object of the present invention is to provide an impact force absorbing device that can reduce the amount of materials and weight while increasing the yield strength.

[Summary of the invention]

The feature of the present invention is that an overlapping part is formed in the support wire of the avalanche/rockfall prevention body, and the overlapping part is tightened by a tightening member, so that the impact load applied to the prevention body is absorbed by the overlapping part. It is in what you do to be done.

[Action of the invention]

When a load is applied to the preventive body, the overlapping state of the supporting wire rods is released against the tightening force of the tightening member.

[Embodiments of the invention]

Figures 1 to 3 show a first embodiment in which a prevention wall is used as a prevention body, in which a plurality of columns 3 having hinge parts 3a are erected on a concrete foundation 2 provided on a slope 1, and A plurality of cross beams 4 are provided on the support column 3 to form a prevention wall 5, and a support wire 6 such as a wire rope or piano wire is fixed to the top of the prevention wall 5, and the wire 6 is connected to a portion above the prevention wall 5. It is fixed to the slope 1 with an anchor 7.

The support wire 6 includes an upper wire 6a and a lower wire 6b as shown in FIG.
At the same time, the lower end side of the lower wire member 6b is fixed to the top of the prevention wall 5, and the lower end side of the upper wire member 6a and the upper end side of the lower wire member 6b are overlapped with each other to form an overlapping portion A. The upper wire rod 6a and the lower wire rod 6b of this overlapping portion A are tightened and fixed by two tightening members 8 at a distance. Reference numeral 9 denotes terminal protrusions fixed to respective ends of the upper wire 6a and the lower wire 6b. In that case, the tightening member 8
(Insert the U-bolt 8a through the stop plate 8b as shown in Figure 7)
It shows what is screwed onto 8C.

When an impact load from falling rocks or an avalanche is applied to the prevention wall 5, tensile force acts on the support wire 6, causing the upper wire 6-a and the lower wire 6b to slide against the tightening force of the tightening member 8. try to move. Then, at the same time that the tensile force applied to the wire rod 6 exceeds the limit static friction resistance by the tightening member 8, the upper wire rod 6a is applied to the overlapping part.
As shown in FIG. In addition, when a larger tensile force is applied, the overlapping part A
The two fastening members 8 are further slid in the direction of releasing the state, and the two fastening members 8 come into contact with each other as shown in FIG. 5(2).

In this way, the upper wire rod 6a and the lower wire rod 6b of the overlapping part A slide against the clamping force of the clamping member 8, resulting in a considerable amount of energy loss due to friction, resulting in falling rocks and It absorbs the impact force of an avalanche.

FIG. 4 shows a second embodiment, in which the same parts as in the above embodiment are denoted by the same reference numerals.The main part of one support wire 6 is formed into a ring-shaped loop 10 to form an overlapping part B. However, this overlapping portion B is tightened and fixed by two tightening members 8 at a distance. Therefore, when an impact load from falling rocks or an avalanche is applied to the prevention wall 5, the tightening member 8
As shown in FIG. 6(a), the wire rod 6 moves one step in the direction of releasing the loop 10 against the tightening force, and the loop 10 becomes locked to the two tightening members 8. When a heavy load of σ1 is further applied, the wire rod 6 further extends and moves in the direction of releasing the overlapping portion B, as shown in FIG. In this way, the loop 100 and the wire rod 6 of the overlap part B
While moving against the clamping force of the clamping member 8, a considerable amount of energy is lost due to friction, resulting in falling rocks and
It absorbs the impact force of an avalanche.

In addition, the overlapping part A in each of the above-mentioned embodiments.

B shows the case where they are overlapped twice, but they may be overlapped three times or more, and the case where the number of tightening members 8 is two is shown, but it may be one or three or more. Moreover, although the case where the pillar of the preventer is installed upright on the concrete foundation via the hinge part is shown, it may be provided rotatably. In addition, regarding the material and diameter of the wire itself, the tension, initial impact force, and
It is determined based on the probability of impact force generation, the importance of the structure, etc.

〔Effect of the invention〕

In the present invention, an overlapping part is formed in the support wire of the avalanche/rockfall prevention body, and the overlapping part is tightened by a tightening member. Therefore, the impact force on the pressure receiving surface of the above prevention body is absorbed and alleviated by the overlapping part, and is reduced. It is possible to use large-scale materials and construction equipment, and has excellent effects.

[Brief explanation of drawings]

Figures 1, 2, and 3 show the first embodiment; Figure 1 is an overall front view, Figure 2 is a plan view of the same, Figure 3 is a front view of the overlapping part, and Figure 4 is a front view of the overlapping part. Front view of the second embodiment, Fig. 5 (A) (B)
is a front view showing the operating state of the first embodiment, and FIG. 6 (5) (
2) is a front view showing the operating state of the second embodiment, and FIG. 7 is a sectional view of the tightening member. 5. Preventing wall 6. Supporting wire A, B. Overlapping portion patent applicant Applicant Nippon Samicon Co., Ltd. Figure 2 Figure 3 s4 Figure 5 ll6a Figure 7

Claims (1)

[Claims] An impact force absorbing device for preventing avalanches and falling rocks, characterized in that an overlapping portion is formed in the support wire of the avalanche/rock falling prevention body, and the overlapping portion is tightened by a tightening member.