Composite structure and stone fall prevention method

Abstract

To prevent stone fall.SOLUTION: A composite structure 10 comprises: a plurality of rocks 12; and a foam body 14 that contains the rocks 12. By constructing the composite structure 10 in which the foam body 14 is formed so as to contain the rocks 12, the positional relationship of the rocks 12 can be maintained by the foam body 14, and thus rolling of the rocks 12 caused by shifting of the positional relationship of the rocks 12 can be prevented. The composite structure 10 can have a water passage 16 for passing water between the foam body 14 and the ground surface.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a composite structure and a method for preventing rockfall. [Background technology]

[0002] Patent Document 1 discloses a rockfall prevention method for preventing the falling and sliding of loose rocks on a slope. This method involves constructing a retaining wall below the target loose rock until it covers all or part of the loose rock, thereby supporting the loose rock. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-251073 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the method described in Patent Document 1 requires a large amount of concrete to build a retaining wall, as well as large-scale equipment such as frames and heavy machinery for pouring the concrete. For this reason, there is a demand for a simpler technology to prevent rockfalls.

[0005] The present invention has been proposed in view of the above-mentioned problems associated with the conventional technology, and aims to provide a composite structure that can prevent rockfalls and a method for preventing rockfalls. [Means for solving the problem]

[0006] A first aspect of the composite structure according to the present invention is Several rocks and The present invention also provides a foam containing the plurality of rocks.

[0007] A second aspect of the composite structure according to the present invention is the composite structure according to the first aspect, There may be a water passage between the foam and the ground.

[0008] A first aspect of the method for preventing rockfall according to the present invention includes: The gist of the invention is that the foam is formed so as to enclose a plurality of rocks, thereby maintaining the relative positions of the plurality of rocks.

[0009] A second aspect of the method for preventing rockfall according to the present invention is the same as the first aspect of the method for preventing rockfall, A water passage may be provided between the foam and the ground. Effect of the Invention

[0010] According to the composite structure of the present invention, the foam maintains the relative positions of multiple rocks, thereby preventing rock falls. According to the method for preventing rockfalls of the present invention, rockfalls can be prevented by maintaining the relative positions of multiple rocks using a foam. [Brief description of the drawings]

[0011] [Figure 1] 1 is a longitudinal sectional view showing a composite structure according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view showing a composite structure according to an embodiment. [Diagram 3] 1A to 1C are explanatory diagrams showing a manufacturing process of a composite structure according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Next, the composite structure and the method for preventing rockfall according to the present invention will be described below with reference to the accompanying drawings, using preferred examples. Note that the embodiments and drawings described below are merely examples of the present invention, and are not intended to limit the present invention to these configurations, and may be modified as appropriate without departing from the scope of the present invention. EXAMPLES

[0013] As shown in FIG. 1, a composite structure 10 according to the embodiment includes a plurality of rocks 12 and a foam 14 containing the plurality of rocks 12. The rocks 12 in the present disclosure refer to relatively hard lumps including rocks and stones. The rocks 12 may be natural or artificial. The size of the rocks 12 is not particularly limited. Furthermore, the rocks 12 may not only be entirely exposed above the ground 20, but also be partially buried in the ground. That is, the plurality of rocks 12 may be a collection of only those entirely exposed above the ground 20, a collection of only those partially buried in the ground, or a collection of both those entirely exposed above the ground 20 and those partially buried in the ground.

[0014] The multiple rocks 12 may be in a positional relationship where the rocks 12 are in contact with each other, such as overlapping each other (see FIG. 1 or FIG. 2), or may be in a positional relationship where the rocks 12 are spaced apart from each other. Here, the multiple rocks 12 may be in a positional relationship formed naturally, or may be in a positional relationship formed by artificially moving the rocks 12. Furthermore, the multiple rocks 12 are not limited to being placed on a sloping ground or a slope such as a cliff, and may also be placed in a relatively flat place such as a riverbank.

[0015] As shown in FIG. 1, the foam 14 may be disposed so as to enclose some of the rocks 12 and expose the remaining portions of the rocks 12 to the outside of the foam 14, or may be disposed so as to enclose the entire rocks 12. The foam 14 may be disposed not only so as to surround the outside of the rocks 12, but also so as to enclose the inside of the rocks 12. The foam 14 may be disposed between adjacent rocks 12 in the rocks 12. For example, when adjacent rocks 12 are in contact with each other, it is preferable to dispose the foam 14 so as to enclose the contact point. In this way, the composite structure 10 maintains the positional relationship of the rocks 12 by the foam 14 enclosing the rocks 12.

[0016] The foam 14 is preferably a polyurethane foam. The foam 14 is not particularly limited, but may be, for example, a polyurethane foam having a strength of 120 kN / m 2 , density 36kg / m 3 Among these, in-situ foamed polyurethane foam is preferable from the viewpoints of light weight, ease of application, adhesiveness to rocks 12, etc.

[0017] As shown in FIG. 1, the composite structure 10 has a water passage 16 provided between the foam 14 and the ground 20. In the embodiment, the water passage 16 is formed by passing a pipe between the rocks 12. The water passage 16 is not limited to a pipe, but may be a gutter or a member having water permeability, or may be a gap formed by placing the foam 14 away from the ground 20. If there is a gap between the foam 14 and the ground 20 before the composite structure 10 is formed, water such as rainwater flows through the gap. Therefore, by providing the water passage 16 between the foam 14 and the ground 20, a water passage is secured as before. The water passage 16 may be provided along the existing water passage that flowed between the multiple rocks 12 before the composite structure 10 was formed. In addition, for example, in the case of a slope, the water passage 16 may be provided so as to pass from the upstream side to the downstream side of the composite structure 10 (see FIG. 2). In this way, by providing the water passage 16 in the composite structure 10, adverse effects on the existing water passage can be reduced. On the other hand, if the waterway 16 is not provided, the water will lose its previous path and be blocked, which may cause landslides or the like.

[0018] The composite structure 10 can be obtained, for example, as follows. A plurality of rocks 12 are gathered in a certain positional relationship (see FIG. 3(a)). First, a pipe that serves as a water passage 16 is arranged between the rocks 12 (see FIG. 3(b)). At this time, it is preferable to confirm the path of water passing through the rocks 12 in advance and arrange the pipe so as not to change the path of the water. Next, a panel 22 such as plywood is arranged around the rocks 12 as a formwork for the foam 14 (see FIG. 3(c)). At this time, it is sufficient that the panel 22 can prevent the foam raw material from flowing around the rocks 12 while the foam raw material is in a liquid state. For example, the panel 22 may be arranged on the lower and lateral sides of the slope of the rocks 12, and the panel 22 arranged on the upper slope of the rocks 12 may be omitted. For example, if polyurethane foam is used as the foam 14, a mixed liquid of liquid A (polyol) and liquid B (isocyanate) is sprayed on-site onto the rocks 12 in the panel 22 to foam, thereby forming the polyurethane foam. This spraying operation is repeated from the bottom up to form the foam 14 containing the rocks 12 (see FIG. 3(d)). The liquid foam raw material flows down between the rocks 12 and foams in the gaps between the rocks 12, forming the foam 14 not only around the rocks 12 but also between the rocks 12. The panel 22 is then removed to obtain the composite structure 10 (see FIG. 3(e)).

[0019] In the composite structure 10 of the embodiment, a plurality of rocks 12 are encapsulated in a foam 14. In the composite structure 10, the positional relationship of the plurality of rocks 12 is maintained by the foam 14, so that the displacement and movement of the rocks 12, which are the initial triggers of rockfall, can be suppressed. Furthermore, if the positional relationship of the plurality of rocks 12 is maintained, the mutual balance is maintained by the support and interlocking of the plurality of rocks 12, and it is possible to prevent the rocks 12 from starting to roll. In this way, by the simple method of forming the foam 14 so as to encapsulate the plurality of rocks 12, the positional relationship of the plurality of rocks 12 can be maintained, thereby preventing rockfalls.

[0020] The commonly used foot-solidification method supports the rock 12 from below to suppress the rolling of the rock 12, so that specialized knowledge is required for designing the position, size, and range of the retaining wall that supports the rock 12. On the other hand, the rock fall prevention method of the present disclosure can be constructed by simply maintaining the positional relationship of the multiple rocks 12 by enclosing the multiple rocks 12 in the foam 14. In addition, even if the shape of the rock 12 or the shape of the ground 20 is complex, the foam 14 can be made to follow the shape of the rock 12 or the ground 20, and is excellent in workability even in an environment with restrictions such as a slope. In addition, by changing the hardening speed, raw material viscosity, cell state, etc. of the foam 14, the foam 14 can be spread to the recesses of the rock 12 and the gaps of the rock 12. Therefore, rock falls can be easily prevented by changing the molding conditions of the foam raw material without complex design like a retaining wall.

[0021] The method for preventing rockfall may be used in combination with a rope laying method, a wire rope hanging method, a ground anchor method, etc. Furthermore, the method for preventing rockfall may be used to prevent garden stones, stone lanterns, etc. from falling. [Explanation of symbols]

[0022] 10 Composite structure, 12 Rock, 14 Foam, 16 Waterway, 20 Ground

Claims

1. Several rocks and A foam containing the plurality of rocks. A composite structure comprising:

2. 10. The composite structure of claim 1, further comprising a water passage between said foam and the ground.

3. By forming a foam so as to contain a plurality of rocks, the relative positions of the plurality of rocks are maintained. A method for preventing rockfalls.

4. The method for preventing rockfall according to claim 3, further comprising providing a water passage between the foam and the ground.

Images