JP2002294711A - Vegetation mat and working method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vegetation mat which is lightweight, low in cost, and has sucking prevention effect and is capable of withstanding a rapid running water without being peeled off. SOLUTION: A lightweight anti-corrosive sheet of having the sucking prevention effect is mounted as one united body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vegetation mat used for vegetation revetment such as a river embankment and a method of constructing the mat.

[0002]

2. Description of the Related Art For example, in a vegetation revetment on a slope of a river embankment, (1) an artificial turf in which seeds and fertilizers are attached to one side of a palm mat through thin cotton wool is used as a slope on a water surface of a river. A method is adopted in which the seeds and fertilizer are attached to the lower side (river table method), but the palm mat is a negative pressure generated by running water flowing on the artificial turf attached to the slope. Suction of the soil on the slope, which is light and inexpensive while having a measure that is not affected by the so-called sucking action, while the palm mat has a weak strength, for example, a high flow velocity that occurs when the river rises in water. There was a problem that the artificial turf was easily peeled off due to the flowing water.

In order to solve this problem, the applicant of the present invention has proposed (2) a vegetation mat (Japanese Patent Application No. 11-1) in which wild grass as a lawn mat is integrated with a flexible net material.
No. 81262) has been filed earlier.

[0004]

In this case, although the vegetation mat can withstand high-speed flowing water by the net material, the wild grass is expensive and the weight of the wild grass is reduced by the net material. , The standard of the rectangular vegetation mat is, for example, 2 m × 2 to 3 m (40 k
g to 60 kg), it is necessary to use a large number of joints between the vegetation mats having a small standard for attaching work, and to use a large amount of binding material to reinforce the joints having low strength. There were problems that it was troublesome, expensive in terms of materials and construction, and that the production of the vegetation mat itself was complicated and time-consuming.

The present invention has been made in view of such circumstances, and is lightweight, inexpensive, has an effect of preventing suction,
It is another object of the present invention to provide a vegetation mat that can withstand running water having a high flow velocity without peeling off, and a method for constructing the mat.

[0006]

To achieve the above object, a vegetation mat according to the present invention comprises a flexible and strong net and a lightweight, corrosion-resistant material having a suction-preventing effect. The sheet and the sheet are integrated.
1).

This vegetation mat is used as a vegetation revetment method for laying on a river embankment slope and then performing vegetation work such as sticking of wild turf or seed spraying work thereon.
2).

In another aspect of the present invention, a lightweight and corrosion-resistant material sheet having a suction-preventing effect is mounted on a flexible and strong net. A vegetation mat (claim 3) provided with at least a plant seed is provided in the direction. Furthermore, the sheet made of the corrosion-resistant material has a mesh that allows the rhizome or foliage of the plant to pass therethrough, and is made of a mesh-shaped nonwoven fabric that has an effect of preventing the suction of earth and sand (claim 4).

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a vegetation revetment on a slope N such as a river embankment. FIG. 2 shows a vegetation mat 1 of the present invention used for the vegetation revetment.
Shows the operation of the vegetation mat 1, and FIG. 5 shows the vegetation revetment viewed from the side. In FIG. 1, R in FIG.
Is the direction of flow of water.

The vegetation mat 1 is, for example, 1-3 m ×
It can be a standard of 10 to 30 m, the specification of the earlier application,
The standard of the vegetation mat shown in the drawing, that is, 2mx3m
It is a rectangular shape several times larger than that.

The vegetation mat 1 is formed by integrating a net 2 having flexibility and strength (to be described later) with a sheet 3 of a corrosion-resistant material which is lightweight and has a suction-preventing effect.

The sheet 3 of the corrosion resistant material is a non-woven fabric made of synthetic resin fibers of the corrosion resistant material. For example, a nonwoven fabric is formed using nylon, vinylon, or polyester fiber, and the nonwoven fabric is adhered to a flexible net 2 by bonding or sewing with a water-soluble glue such as polyvinyl alcohol.

The vegetation mat 1 of the present invention thus formed is attached to a river embankment slope as shown in FIG. 1 to protect the river embankment slope. In this way, the strong net protects the slope of the river embankment, and the soil attached to the slope protects the slope soil even if the water level rises due to the rise of water in the river due to the anti-suction sheet Without the river dike slopes being protected. Furthermore, a wild grass 4 in the form of a roll, for example, is attached thereon to complete the vegetation revetment.
When formed in this manner, the rhizome of the wild grass is entangled and integrated with the flexible net 2 and the sheet 3 of the corrosion-resistant material, and furthermore, the wild grass is attached to the soil of the river embankment slope. Spread rhizomes to form a strong vegetation revetment structure.
In some cases, a thin covering, for example, 2-3 cm, is laid on the vegetation mat 1. In this case, the rhizome spreads in the above-mentioned covering soil. Form a revetment structure. When soil is used in combination, it is used when there is a risk of drying or when the amount of soil adhering to the grass is relatively small (thin).

When the vegetation revetment structure is formed, the water level of the river rises due to flooding or the like, and even if the river water is immersed in the vegetation revetment, a strong net and a withstand function having a function of preventing suction are provided. Since the sheet of corrosive material and the wild grass with the rhizome strongly entangled with them protect the river embankment slope, it is not lifted up by the flowing water of the river and peeled off. In particular, the sheet 3 made of the corrosion-resistant material having an excellent suction-preventing effect makes it possible to form a stable seawall structure without the soil on the river slope being sucked.

In the above embodiment, an example was given in which the wild grass 4 was stuck on the vegetation mat laid on the river slope, but in addition to the vegetation work by sticking the wild grass 4, the plant So-called seed spraying (thick base material spraying), which mixes and sprays seeds, fertilizers, soil conditioners, organic materials, etc., and attaches plant seeds to nets and paper cloth with vegetation materials such as fertilizers It is also effective to lay and construct a greening sheet or a vegetation base called a greening mat.

On the other hand, the flexible material used in the present invention has
The strong net 2 is made of a highly durable fiber such as nylon, polyester, aramid, carbon, glass, polyacetal, or the like, and has a mesh size of 5 mm to 25 mm.
(Preferably 5 to 7 mm) is formed into a lattice shape, but may be braided into a mesh having the same meshing as above using the above-mentioned fiber filaments. The lattice-like body and the mesh-like body may be overlapped, and the tensile strength per 1 m of the width is set to about 0.5 to 4.0 tons. This is because the flow velocity of the water flowing through the river is 2.
It has sufficient strength to withstand a fluid force of 0 to 3.5 m / S.

This net 2 has a weight of 2 per m 2.
Light from 00 grams to 250 grams.

As the sheet 3 of a corrosion-resistant material having a function of preventing suction and used in the present invention, a non-woven fabric having a basis weight of about 25 to 70 g made of synthetic fibers such as nylon, vinylon and polyester fibers can be used.

As a more preferable example of the nonwoven fabric, a mesh-shaped nonwoven fabric is used (see a partially enlarged view of FIG. 2).
This mesh-shaped nonwoven fabric is made of synthetic fibers such as polyester, for example, in the vertical and horizontal directions, for example, 0.5
Sparse part 5 and dense part 6 formed with a width of 0.3 to 5.0 mm between
And are alternately arranged. That is, the sparse portion 5 is such that the material forming the nonwoven fabric is reduced or absent, so that the buds and roots of the plant can easily pass through, and the sparse portion 5 is impervious or difficult to pass through. The dense portion 6 has a strength such that the material forming the non-woven fabric is densely packed more than a certain amount and does not pass or does not pass through the buds, roots and soil of the plant. It is the part that is. The distance A between two adjacent dense portions 6 is formed such that the distance A from the center of one dense portion 6 to the center of the other dense portion 6 is 0.5 to 1.0 mm. I have. When the width of the sparse portion 5 is B, the width B is formed to be 0.3 to 5.0 mm. In the present embodiment, the sparse portion 5 is made of
In the range of × 10 mm, 5 to 6 holes in the horizontal direction and 3 to 4 holes in the vertical direction are formed as holes having a diameter of about 1.0 mm, and the basis weight of the nonwoven fabric is 30 to 70 g / m 2.

If the width of the sparse part 5 is smaller than 0.3 mm, it will be difficult for plant buds and roots to pass therethrough. In addition, the effect of preventing suction by the nonwoven fabric is reduced. Here, the sparse portion 5 is formed as a hole, and the width B is relatively large (for example, 5.0 mm).
In this case, it is considered that the earth and sand slightly pass through the sparse portion 5, but in such a case, a thin thread 5a as shown in a partially enlarged view of FIG. In this state, the sediment becomes more difficult to pass through due to the presence of the filament 5a. That is, when the sparse portion 5 is formed in a size that allows a certain amount of earth and sand to pass therethrough, the sparse portion 5 includes the thread-like body 5a and the net-like body (not shown). If it is arranged, it will not pass through or hard to pass through soil, and plant buds,
If an obstructing member that exerts the function of allowing the roots and foliage to pass is stretched (provided), earth and sand will be more difficult to pass by the presence of the obstructing member. Also, when the buds, roots and foliage of the plant are inserted into the sparse part 5,
Almost no earth and sand can pass.

According to a second aspect of the present invention, a sheet 3 of a lightweight and corrosion-resistant material having an effect of preventing suction is mounted on the flexible and strong net 2 described above. Is a vegetation mat 1 having at least plant seeds mounted on the other surface of the sheet 3. This vegetation mat 1 can use, as plant seeds, plants that have little discomfort with the surrounding vegetation, such as native wild turf, chigaya, Japanese pampas grass, mugwort, and medhagi. In order to exhibit its function, the seeds of the plant, in which germination is early and vigorous initial growth is strong, and the rhizome of the plant is entangled with the flexible net 2 and the suction-preventing sheet 3 in a short period of time, that is, the so-called western grass, Leaping red fescue, tall fescue, bluegrass, bentgrass, barmudagrass and the like are more preferable. Of course, it is also preferable to mix these native species and western turf at an appropriate ratio.

In another embodiment of the present invention, the vegetation mat 1 is provided with a coarse net 7 and a thin cotton-like fiber.
(Thin cotton wrap) glued, plant seeds using a water-soluble glue such as polyvinyl alcohol on this thin cotton wrap,
A vegetation base (so-called artificial turf) to which a vegetation material 8 composed of a fertilizer, a soil conditioner, or the like is bonded may be attached or integrated by bonding or sewing. In this case, the vegetation material 8 such as seeds
May be mixed with a polymer soil coagulant. As the polymer soil coagulant, polyacrylamide, polyethylene oxide, polyvinyl alcohol, and the like can be used. This polymer soil coagulant has an action of coagulating the soil particles in the muddy water into large particles when the soil on the back side of the vegetation mat 1 is muddy by river water. With this polymer soil flocculant, the effect of preventing the vegetation mat 1 from sucking out can be improved.

The reason why the staple cotton (thin cotton wrap) is used is that it does not hinder the germination and growth of the plant and is dissolved by water. Creep paper, polymer film or starch film,
There are water-soluble paper with cold gauze, souff-based nonwoven fabric, pulp-based nonwoven fabric, and the like. Therefore, these may be used instead of soft cotton (thin cotton wrap).

When the artificial turf is mounted on the vegetation mat 1, the coarse net 7 constituting the artificial turf may be mounted on the ground side, that is, in contact with the slope soil. In this way, when the construction is applied to the slope of a river embankment, the coarse net 7 serves as a protective layer for the vegetation material 8 such as seeds, so that even if the river rises and the water level rises to the vegetation mat 1 construction site. In addition, it is possible to prevent the seeds from being washed away. As the coarse net 7, a net made of organic fibers such as jute and palm or a net made of plastic fibers such as polyethylene can be used. In particular, the plastic fiber is more suitable because it has strength even if it is thin and does not hinder the adhesion of the vegetation mat 1 to the slope in terms of durability.

Further, since the artificial turf has a light weight of 200 g to 600 g per m 2, even if the vegetation mat 1 is formed using this artificial turf, it can be finished as a whole with a light weight.

Accordingly, the vegetation mat 1 can be made lighter than the vegetation mat with the rhizomes of the wild grass shown in the conventional example. Therefore, as described above, for example, the standard of the rectangular vegetation mat 1 is 1 mx Even if it is large, such as 30 m, or 2 m × 20 m, the weight can be made sufficient for the operator to carry (for example, about 10 kg to 20 kg). As a result, it is possible to solve the problem caused by the fact that the conventional standard requires a large number of joints because the standard is small.

Next, the procedure for laying the vegetation mat 1 on the vegetation revetment on the river slope N will be described. Figure 1
As shown in FIG. 4, a flooded area at the bottom of the Hoshiri or a part inundated for a considerable period of time is dug appropriately, and, for example, a cage mat 10 is laid in this excavated part. Is).

At this time, a net 9 similar to the net 2 is laid on the lower side of the basket mat 10 over an appropriate width, and its upper side 9a is placed on the upper surface N of the basket mat 10.
Side (the revetment side). On the other hand, a part of the net 11 similar to the net 2 is protruded in the vicinity of the highest water level at the time of the assumed rising water, preferably in the revetment area slightly higher than the highest water level H as shown in the drawing. And bury it.

In this embodiment, a net portion 2 having a width of, for example, 50 mm is provided on both sides of the vegetation mat 1 in the width direction.
a, 2b overhang, and on one side in the longitudinal direction of the net 2,
For example, a net portion 2c having a width of 250 mm is protruded, and a net portion 2d having a width of 50 mm is protruded on the other side of the net 2 in the longitudinal direction.

Then, the worker stretches the vegetation mat 1 on the slope N from, for example, the downstream side to the upstream side of the revetment area and from the lower side to the upper side of the revetment area. At this time, as for the vegetation mat 1 on the lower side of the revetment area, the other net portion 2d of the net 2 is superimposed on the upper side 9a of the net 9 laid under the cage mat 10 and protruded from above. An anchor 15 is cast on both of these 2d and 9a. The upper and lower vegetation mats 1 and 1 are connected to the upper net portion 2c of the lower vegetation mat 1.
Then, the lower net portion 2d of the upper vegetation mat 1 is overlaid from above, and the anchor 15 is cast on the two nets 2d and 2c.

The upper net portion 2c of the vegetation mat 1 on the upper side of the revetment area is replaced with a net 11
Are overlapped from above on the protruding side portion 11a of
At this time, the upper end of the vegetation mat 1 may exceed the protruding side portion 11a due to the length of the vegetation mat 1 in this case. An anchor 15 may be cast on the overlapping portion with the protruding side portion 11a, or the net 2 may be cut, the length of the vegetation mat 1 may be adjusted, and the two 2c and 11a may be overlapped. It is good.

On the other hand, regarding the vegetation mat 1 stretched from the downstream side to the upstream side of the revetment area, the upstream net portion 2b of the downstream vegetation mat 1 is attached to the vegetation mat 1 of the upstream side. The downstream side net portion 2a is overlapped, and an anchor (not shown) is placed between the two side portions 2a and 2b, and the upstream side net portion 2b of the vegetation mat 1 is overlapped with the net 14. Together, these two 2b, 1
4 is connected by connecting means (not shown) such as a coil wire or a staple, and a downstream net portion 2a of the upstream vegetation mat 1 is superimposed on the superimposed portion,
An anchor (not shown) is cast on these three members 2a, 2b, 14.

The overlapping portions of the vegetation mats 1 and 1 adjacent to each other in the vertical and left directions and the overlapping portion of the vegetation mat 1 and the net 11 at the upper part of the revetment area are the same. The nets 2 and 11 are engaged with connecting fittings (not shown) buried in the seawall in advance.
In addition, the vegetation mat 1 is covered with soil (not shown) so as to cover the vegetation mat 1 as necessary. As described above, the method of extending the vegetation mat 1 vertically and vertically in the length direction of the river embankment slope has been described. However, this method may be adjusted to be horizontally long in the width direction of the levee. Since the vegetation mat is stretched horizontally in the direction parallel to the direction, the number of connection points of the vegetation mat is reduced as compared with the method in which the vegetation mat is stretched vertically, and the possibility of peeling by running water can be reduced. .

The overhanging net portions 2a to 2
d at each end to prevent misalignment when connecting the net.
It is effective to form a dense mesh portion with a width of about 5 cm.

Next, the operation of the vegetation mat 1 will be described with reference to FIGS.

The initial stage after the vegetation mat 1 of the first invention is stretched on the slope N is in a state as shown in FIG. 3 (A). That is, a flexible and strong net 2
The sheet 3 (non-woven fabric) of a corrosion-resistant material that has a suction-preventing effect and firmly covers the slope of the river embankment, especially if the river rises and the water rises, the sheet 2 of the corrosion-resistant material The erosion of the slope can be prevented without the surface soil being sucked. When wild grass 4 is stuck on the vegetation mat 1, the rhizome 4a of the wild grass 4 is entangled with the net 2 and the sheet (non-woven fabric) 3 of the corrosion-resistant material to form a vegetation revetment structure in which these are integrated. (Fig. 3 (B)).

The initial stage after the vegetation mat 1 of the second invention is stretched on the slope N is in a state as shown in FIG. 4 (A). That is, a flexible and strong net 2
Sheet of non-corrosive material with non-sucking prevention effect
3 is to cover the slope of the river embankment firmly, especially if the river rises and the water rises, the sheet 2 of the corrosion resistant material prevents the slope soil from being sucked out and prevents the erosion of the slope. Can be planned. In the case of the second invention, the vegetation mat 1
Since the plant seeds and other vegetation materials 8 are mounted, the plant seeds germinate and grow after construction, and the rhizomes 8a are extended to the flexible net 2 and the corrosion-resistant sheet 3 so that the rhizomes 8a
Entangled with them to form an integrated vegetation revetment structure, and the rhizomes 8a can infiltrate the soil on the river embankment slope to strengthen the slope of the river embankment, and the rivers rise due to flooding, etc. Even if the water level rises and flowing water flows at a high velocity over the surface of the river embankment, the river embankment is protected without erosion (Fig. 4 (B)).

[0038]

As described above, the present invention provides a vegetation mat comprising a flexible and strong net and a sheet of a corrosion-resistant material which is lightweight and has a suction-preventing effect. Alternatively, a sheet of a lightweight and corrosion-resistant material having a suction-preventing effect is mounted on a flexible and strong net, and at least a plant seed is mounted on the other surface of the mat of the corrosion-resistant material. Since the vegetation mat is laid on a vegetation revetment on a slope such as a river embankment, the following effects are obtained.

(1) For example, a rectangular standard is 1 mx 30
It is possible to manufacture a product (vegetation mat) according to the law length, such as m or 2 mx 20 m, and it is lightweight, so that the construction efficiency can be improved. (2) The tensile strength per 1 m width is, for example, 0.5
The plant is entangled with a strong net of about 4.0 tons, so that it can withstand running water. (3) Inexpensive vegetation revetment works can be implemented. (4) (a) A method of stretching a palm mat, for example, after spraying a vegetation material such as a plant seed, or (b) After constructing a flexible and strong net, cover the soil, for example, about 10 cm, and apply a soil. There is no need to perform a plurality of steps such as spraying of vegetation material, and the vegetation revetment can be performed by only one step of laying the vegetation mat of the present invention on the slope (second invention).

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a vegetation revetment against a slope of a river embankment to which a vegetation mat according to an embodiment of the present invention is applied.

FIG. 2 is a perspective view of the vegetation mat of the embodiment as viewed from a lower surface side.

FIG. 3 is an operation explanatory diagram in the embodiment.

FIG. 4 is an operation explanatory diagram in another embodiment.

FIG. 5 is a longitudinal side view of a vegetation revetment, which is a part of FIG. 1 taken out and illustrated.

[Explanation of symbols]

Reference numeral 1 denotes a vegetation mat, 2 denotes a flexible and strong net, and 3 denotes a sheet made of a corrosion-resistant material having a suction-preventing effect.

Claims (4)

[Claims] 1. A vegetation mat comprising a flexible and strong net and a sheet of a corrosion-resistant material which is lightweight and has a suction-preventing effect. 2. A vegetation revetment method in which the vegetation mat according to claim 1 is laid on a slope of a river embankment, and vegetation work such as sticking of wild grass or seed spraying is performed thereon. 3. A flexible and strong net is provided with a sheet of a light-weight, corrosion-resistant material having a suction-preventing effect, and at least the plant seed is provided on the other surface of the sheet of the corrosion-resistant material. A vegetation mat characterized by being attached. 4. The vegetation mat according to claim 1, wherein the sheet of the corrosion-resistant material is a nonwoven fabric having a mesh made of synthetic fibers.