JP2002302912A - Avalanche prevention block and avalanche prevention structural body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an avalanche prevention block and an avalanche prevention structural body using it capable of efficiently forming a projection part on a slope at a low cost for effectively preventing an avalanche. SOLUTION: When this avalanche prevention block 3 formed of a synthetic resin reinforced by multiple fibers is fixed on the slope 1 formed by cut earth, the projection part is formed. The projection part resists a slide of an accumulated snow layer. The avalanche prevention block is provided with a base plate fixed to the slope in substantially parallel to it, a hollow column part standing on the base plate and having a rectangular cross section, and a top plate closing the upper end part of the column part. In the column part, a member thickness of a side face member positioned on the higher side of the slope is gradually increased from a connection part with the top plate to a connection part with the base plate. A member thickness of the base plate is gradually increased from a connection part with the side face member positioned on the lower side of the slope to a connection part with the side face member positioned on the higher side of the slope.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an avalanche prevention structure provided on a slope in an area with a lot of snow and preventing avalanches from occurring, and an avalanche prevention block used for the structure.

[0002]

2. Description of the Related Art A large-scale slope is formed when cutting is performed for the construction of a road or a railway or the development of land in a mountainous area. Such slopes are generally planted with protective works or turf etc. to prevent slope collapse, but if there is a lot of snow on this slope, the snow will not There is a danger of avalanches as the layers slide down.

For this reason, measures to prevent avalanches have been considered. For example, Japanese Utility Model Publication No. Sho 63-6242 discloses that a large number of prismatic concrete blocks are projected on a slope.
This shows a structure for preventing the snow layer from sliding down.

[0004] The concrete block is shown in FIG.
As shown in FIG. 4 (b), a concrete 102 is cast in place so as to be integrated with a sill 101 and the like provided for protecting a slope, as shown in FIG. There is a method in which a precast concrete block 111 is fixed to a frame or a foundation block 113 with anchor bolts 112. Further, as shown in FIG. 5, a hole is provided in a base block 121 on a flat plate, and a columnar concrete block 122 is fitted into the hole to form a projecting portion.

[0005]

However, the above avalanche prevention structure has the following problems. When a large number of protrusions are formed on a slope by casting concrete on site, workability is poor on the slope, and the efficiency of forming a formwork and placing concrete is deteriorated. For this reason, the construction cost increases. Also, when using a precast concrete block, it is difficult to install the block manually, and a crane or the like is required. For this reason, construction costs are high and workability is poor.

The present invention has been made in view of such circumstances, and an object of the present invention is to form a protruding portion on a slope at low cost and efficiently, and to effectively prevent an avalanche. An avalanche prevention block and an avalanche prevention structure are provided.

[0007]

Means for Solving the Problems In order to solve the above problems, the invention according to claim 1 is made of a synthetic resin reinforced by a large number of fibers mixed therein, and is formed on a slope by substantially the same as the slope. A substrate fixed in parallel, a columnar portion raised from the substrate and having a hollow and rectangular cross section, and a top plate closing an upper end of the columnar portion, wherein the columnar portion is located above a slope. The thickness of the member gradually increases from the joint with the top plate to the joint with the substrate, and the substrate is formed from the joint with the side member located below the slope, An avalanche prevention block in which the thickness of the member gradually increases toward a joint with a side member located on the upper side of the avalanche.

This avalanche prevention block is made of synthetic resin and has a hollow protruding columnar part, so that it is lightweight, and when installed on a slope, an operator can easily carry and install it manually. be able to. And when it is fixed on the slope with anchor bolts and the like locked to the board, the columnar portion protrudes, and when there is a snow layer on the slope,
It is possible to effectively prevent the snow layer from slipping into the snow layer and sliding down. At this time, the weight of the snow layer acts on the protruding columnar part in a direction parallel to the slope,
Since the avalanche prevention block is made of synthetic resin reinforced by fibers and has a large tensile strength,
It is firmly supported on the ground via anchor bolts and the like, and can sufficiently resist the force acting from the snow layer. In particular, the portion where a large stress is applied, that is, the side member of the columnar portion, which is on the upper side of the slope, and the substrate subsequent thereto are thickened, and have sufficient strength and a small increase in weight. .

According to a second aspect of the present invention, in the avalanche prevention block according to the first aspect, the side member located above the slope of the columnar portion goes from the joint with the top plate to the joint with the substrate. The substrate contains more fibers in the slope direction of the slope than in the other direction at a portion above the slope with respect to the joint with the side member located above the slope. Shall be considered.

[0010] In this avalanche prevention block, the fibers mixed into the synthetic resin exert a large tensile stress on the side surface on the upper side of the slope of the columnar portion and on the portion located on the upper side of the slope of the substrate connected thereto. Many will be arranged in the direction. In other words, the protruding columnar portion resists the force of the snow layer to slide down the slope, so that the side surface located above the sloped surface of the columnar portion and the upper side of the boarded surface locked by anchor bolts and the like. Although a large tensile stress is generated in the portion, it is effectively reinforced against the tensile stress, and the reliability is high. The fibers mixed in the synthetic resin are allowed to flow in the above-mentioned direction when the uncured synthetic resin is molded, so that the amount of fibers in that direction can be made larger than in other directions.

According to a third aspect of the present invention, there is provided an avalanche prevention block provided on a slope with a projecting portion substantially perpendicular to the slope.
An avalanche prevention structure fixed by an anchor that penetrates into the ground and is fixed, wherein the avalanche prevention block includes:
The projecting portion is a columnar portion having a hollow rectangular cross section, a top plate closing an upper end of the columnar portion, and a projection extending outward from a lower end of the columnar portion, and substantially projecting from the slope. It has a board | substrate arrange | positioned in parallel and the said anchor provides the avalanche prevention structure latched on the board | substrate of the said avalanche prevention block.

In this structure, since the avalanche prevention block is made of synthetic resin and is lightweight, the work of fixing the avalanche prevention block on the slope can be facilitated and the construction cost can be reduced. In addition, avalanche prevention block,
The anchor that penetrates into the ground and is fixed to the substrate is firmly fixed to the ground. The synthetic resin forming the avalanche prevention block is reinforced with fibers and has sufficient strength. For this reason, even if it acts on the avalanche prevention block in which the weight of the snow layer on the slope is fixed, the snow layer can be firmly supported and the occurrence of an avalanche can be prevented.

According to a fourth aspect of the present invention, in the avalanche prevention structure according to the third aspect, the columnar portion of the avalanche prevention block is formed such that a side member located above a slope is connected to a substrate from a joint portion with a top plate. The thickness of the member gradually increases toward the joint of the substrate, and the substrate is a member from the joint with the side member located on the lower side of the slope to the joint with the side member located on the upper side of the slope. The thickness shall increase gradually.

In this structure, the portion of the avalanche prevention block where a large tensile stress acts is effectively reinforced, and has sufficient strength. Therefore, the weight of the snow layer can be reliably supported, and an avalanche can be prevented.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a structure using an avalanche prevention block according to an embodiment of the invention according to claim 1 or 2, and an avalanche prevention structure according to an embodiment of the invention according to claim 3 or 4. It is the schematic which shows an object. In this avalanche prevention structure, a mortar 2 is applied on a slope 1 formed by cutting, and an avalanche prevention block 3 made of FRP (cured fiber reinforced thermosetting resin) is placed on the mortar 2 by an earth anchor 4. It is fixed. In place of the mortar 2, for example, a grid-shaped concrete frame is provided,
An avalanche prevention block may be fixed thereon.

The earth anchor 4 is formed by drilling an anchor insertion hole in the ground, injecting and solidifying a grout 5 and fixing a steel rod or the like. The weight of the snow layer acts on the avalanche prevention block 3. The avalanche prevention block 3 also has a sufficient pull-out strength so that the avalanche prevention block 3 can be held on the slope 1 even when it is made. Further, it is also possible to embed a sufficient length of the earth anchor 4 in the ground and to introduce a tension to prevent the slope from collapsing.

As shown in FIG. 2, the avalanche prevention block 3 is composed of a substrate 11 abutting on the surface of the mortar 2 substantially parallel to the slope, and a hollow columnar portion 12 raised from the substrate 11. And a top plate 13 that covers the upper end of the columnar portion 12.
It is composed of

The substrate 11 is provided so as to protrude outward from the lower end of the columnar portion 12, and the inside of the columnar portion 12 is open at the lower side. The outer edge of the substrate 11 is substantially rectangular, and through holes 11a for locking the ground anchor 4 are provided near the four corners. And a portion 11 which is above the slope when fixed to the slope.
b has a large thickness (about 35 mm),
The thickness gradually decreases at both side portions 11c at the position where is raised, and is about 10 mm at the lower side 11d of the columnar portion.

The columnar section 12 is hollow with a substantially square cross section, and the size of one side gradually decreases as approaching the upper part. The thickness of the side surface member is the thickest at the joint end with the substrate 11 and is about 10 mm, and the thickness gradually decreases toward the upper end of the columnar portion, and the upper end is about 5 mm. However, the side member 12a on the upper side of the slope is located near the joint with the substrate 11.
b is about 40 mm, which is thicker than other side members, and gradually becomes thinner toward the upper end.

The avalanche prevention block 3 is made of a cured unsaturated polyester resin mixed with glass fiber, and is formed by impregnating a glass fiber sheet with a resin. Molding material (Bulk Molding
Compound).

When the resin mixture containing glass fibers is caused to flow during molding, the glass fibers tend to flow in the direction in which the glass fibers flow, and the side member 12a on the upper side of the slope and the portion 11b on the upper side of the slope of the substrate are As the thickness increases, the vertical direction of the columnar portion 12 (the direction indicated by arrow A in FIG. 2C) or the inclination direction of the slope (the direction indicated by arrow B in FIG. 2C)
The resin is caused to flow so that a large amount of glass fiber is contained in this direction.

The glass fibers having a diameter of about 5 μm to 20 μm are used, and the glass fiber content in the molding material is preferably about 25 to 50% by mass, and particularly preferably 30 to 45% by mass. Glass fiber is continuous filament or 6mm long
A thickness of about 50 mm is desirable, but can be appropriately determined in consideration of a molding method and the like. Specifically, for example, a mat-like glass fiber such as a continuous strand mat or a chopped strand mat or a chopped strand is used.

On the other hand, as the resin, besides the above-mentioned unsaturated polyester resin, a thermosetting resin such as a vinyl ester resin or an epoxy resin can be used. Alternatively, other synthetic resins can be used. For example, a thermoplastic resin sheet containing the mat-like glass fiber or chopped strand can be used as a molding material.

As shown in FIG. 3, a plurality of the avalanche prevention blocks 3 are fixed on the slope 1 at predetermined intervals, and project when the snow accumulated on the slope attempts to slide down. 12 resists the movement of the snow layer 6 and prevents an avalanche.

At this time, a large force acts on the columnar portion 12 in the direction indicated by the arrow C in FIG. 1, that is, in the inclination direction of the slope. As a result, a large bending moment and a shearing force are applied to the vicinity of the lower end of the columnar portion 12, and the vertical direction of the columnar portion (arrow in FIG. 2) is applied to the vicinity of the lower end 12 b of the side member 12 a on the upper side of the slope. (Direction indicated by B). However, the side member 12a is thickened near the lower end and reinforced by glass fiber.
In addition to resisting the tensile stress, the force is transmitted to the ground anchor 4 via the substrate 11. Therefore, the avalanche prevention block 3 has a sufficient strength, and effectively prevents the snow layer 6 from sliding down.

[0026]

As described above, the avalanche prevention block according to the present invention is lightweight, can be easily fixed on a slope, can reduce the construction cost of the avalanche prevention structure, and can sufficiently reduce the construction cost. It has strong strength. Therefore, when the snow layer on the slope is going to slide down, it can be supported and the avalanche can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an avalanche prevention structure according to an embodiment of the invention according to claim 3 or 4;

FIG. 2 is a plan view and a sectional view of an avalanche prevention block according to an embodiment of the invention according to claim 1 or 2, which is used in the avalanche prevention structure of FIG. 1;

FIG. 3 is an overall view of an avalanche prevention structure in which a number of structures shown in FIG. 1 are arranged.

FIG. 4 is a schematic sectional view showing an example of a conventional avalanche prevention block.

FIG. 5 is a schematic sectional view showing another example of the conventional avalanche prevention block.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Slope 2 Floor mortar 3 Avalanche prevention block 4 Earth anchor 5 Grout 6 Snow layer 11 Substrate 12 Columnar part 13 Top plate

Claims (4)

[Claims] 1. A substrate made of a synthetic resin reinforced by a large number of fibers mixed therein, fixed on a slope in a direction substantially parallel to the slope, and a hollow rectangular cross-section which is raised from the substrate and has a rectangular cross section. And a top plate closing an upper end portion of the columnar portion, and the columnar portion has a member thickness from a joint between the side plate located above the slope and a joint with the substrate from a joint with the top plate. Wherein the substrate gradually increases in thickness from the joint with the side member located below the slope to the joint with the side member located above the slope. An avalanche prevention block, characterized in that: 2. A side member located above a slope of the columnar portion includes more fibers in a direction from a joint with a top plate to a joint with a substrate than other directions, and the substrate has a slope on a slope. The avalanche prevention block according to claim 1, wherein the upper part of the slope with respect to the joint with the side member located on the upper side contains more fibers in the slope direction of the slope than in other directions. 3. An avalanche prevention structure in which an avalanche prevention block having a projecting portion substantially perpendicular to the slope is fixed on the slope by an anchor that penetrates into the ground and is fixed. The block is made of a synthetic resin into which fibers are mixed, and the protruding portion is a columnar portion having a hollow rectangular cross section, a top plate closing an upper end of the columnar portion, and extending outward from a lower end of the columnar portion. An avalanche prevention structure, comprising: a substrate disposed substantially parallel to a surface, wherein the anchor is locked to a substrate of the avalanche prevention block. 4. The columnar portion of the avalanche prevention block is such that a side member located above a slope gradually increases in member thickness from a joint portion with a top plate to a joint portion with a substrate. 4. The method according to claim 3, wherein the thickness of the member gradually increases from a joint with the side member located below the slope to a joint with the side member located above the slope. An avalanche prevention structure as described.