JP7773808B2 - Slope protection method - Google Patents

Description

The present invention relates to a slope protection method for protecting a slope such as a slope.

A type of slope protection work is known in which slope protection equipment is installed on a slope (slope), and the equipment consists of a bag-like body containing a substrate together with vegetation seeds (seeds of plants for revegetation) and a net-like member to which multiple bags are attached (Patent Document 1).

With this slope protection work, the accumulated soil and sand runoff by the bag-shaped structure, as well as leaves from the surrounding area, form a vegetation base in the form of small terraces on the mountain side of the bag-shaped structure. This is known as the berm effect, which makes it easier for plants to grow on these berms, resulting in early and successful greening. In other words, the berm effect here refers to the effect whereby the accumulation of soil and sand forms a berm-shaped growth base layer with a gentler gradient than the slope, making it easier for plants to grow on these berms.

However, the base material inside the bags used in this slope protection work is primarily composed of organic matter and vermiculite, and over time the organic matter is consumed and the vermiculite shrinks, which can lead to significant loss of the base material depending on the construction environment. In such cases, this loss can cause the vegetation base that makes up the berm to be washed away or slide down from the gaps that form between the slope and the bag-shaped slope protection device installed on the slope, or from the top of the bag-shaped device, preventing the formation of a vegetation base on the mountain side of the bag-shaped device. As a result, the berm's effectiveness is lost.

One solution is to incorporate a hardening material into the base material or bag-shaped body that hardens when it absorbs water. If the hardening material hardens due to rainfall or other factors, the shape of the bag-shaped body will be maintained, preventing the berm effect from being lost.

Japanese Patent Application Laid-Open No. 2007-56606

However, the above-mentioned conventional slope protection equipment may not provide sufficient berm effectiveness.

The present invention has been made in consideration of the above matters, and an object of the present invention is to provide a slope protection method that can obtain a berm effect well and reliably.

In order to achieve the above-mentioned object, the slope protection method of the present invention is a slope protection method in which a bag-shaped body, the weight ratio of which to store the contents of which is 80 to 160% when the amount is loosely filled, is laid on a slope such as an embankment, and the bag-shaped body has a lattice-shaped high-strength fiber extending in the longitudinal and circumferential directions exposed on the outside of the bag-shaped body, and has a flexibility sufficient to allow it to be stretched along the unevenness of the surface of the slope to be greened, and the bag-shaped body and a net-shaped, mat-shaped or sheet-shaped member without the bag-shaped body attached are laid separately on the slope and integrated, and the bag-shaped body is fixed to the slope by being penetrated by multiple fixing members to obtain a step effect (Claim 1).

The present invention provides a slope protection method that can effectively and reliably obtain the berm effect.

1A is a perspective view showing the configuration of a slope protection device used in a slope protection method according to one embodiment of the present invention in an unfolded state, and FIG. 1B is an explanatory diagram showing a method for storing the slope protection device. FIG. 4 is an explanatory diagram illustrating the configuration of a bag-shaped body of the mortar bag of the slope protection equipment. (A) is a longitudinal cross-sectional view showing the installation state of the slope protection equipment, and (B) and (C) are explanatory diagrams showing the changes in the state of the slope protection equipment laid on a slope. 10A and 10B are explanatory views schematically showing the configuration of a modified example of the bag-shaped body before and after formation. 10A and 10B are explanatory views schematically showing the configuration of another modified example of the bag-shaped body before and after formation. 10A and 10B are explanatory views each schematically showing the configuration of a further modified example of the bag-shaped body. FIG. 10 is an explanatory view schematically showing the configuration of another modified example of the slope protection equipment. 8A and 8B are explanatory diagrams schematically showing changes in the state of the slope protection equipment of FIG. 7 laid on a slope. 10A and 10B are explanatory views each showing a schematic configuration of a modified example of the slope protection equipment.

Embodiments of the present invention are described below with reference to the drawings.

The slope protection method according to this embodiment involves laying the slope protection device 1 shown in Figure 1(A) on a slope N (see Figure 3(A)), which is an example of a slope, to protect and green the slope N.

As shown in Figure 1(A), the slope protection device 1 comprises a substantially rectangular net-like member 2, and a mortar bag 3 and a base material bag 4 that are held (attached) to this net-like member 2.

The net-like member 2 has storage compartments 5 spaced at appropriate intervals along its length. In this example, the net-like member 2 is, for example, 1 m wide and 5-10 m long, with the storage compartments 5 spaced 30 cm apart along its length. In other words, only a portion of the net-like member 2 (slope protection equipment 1) is shown in FIG. 1(A). Each storage compartment 5 accommodates a mortar bag 3 or a base material bag 4. In the example shown in FIGS. 1(A) and 3(A), one out of every three storage compartments 5 accommodates a mortar bag 3, and the remaining storage compartments 5 accommodate base material bags 4. The storage compartments 5 are bag-, cylindrical-, or pocket-shaped, large enough to accommodate the mortar bag 3 or base material bag 4. Each bag 3, 4 is inserted into the storage compartment 5 from one end, thereby being held by the net-like member 2.

The net-like member 2 is made of durable fibers (such as nylon, polyester, aramid, carbon, glass, polyacetal, etc.) or corrosive fibers (such as coconut fibers) and is molded with a mesh size of approximately 5 to 10 mm. It is also possible to layer both of these (durable fibers and corrosive fibers). Furthermore, to further improve strength, the net-like member 2 may be layered with wire mesh (such as tortoiseshell wire mesh or lath wire mesh).

As shown in Figure 1(A), the mortar bag 3 is a long, narrow, cylindrical bag-shaped body 3a with closed ends, which is water- or moisture-permeable and contains dry mortar (an example of a hardening material) 3b that hardens upon water absorption. The bag-shaped body 3a does not contain any materials that create voids (such as base materials that lose mass over time due to fertilizer leaching, etc.), thereby achieving high strength. In this example, the dry mortar 3b is made by mixing granular sand with cement as aggregate. However, the aggregate that makes up the dry mortar 3b is not limited to sand; vermiculite, perlite (pumice), and other materials can also be used. The bag-shaped body 3a can be filled with only the hardening material that hardens upon water or moisture absorption, or with the hardening material mixed with aggregate alone, resulting in a high-strength hardening bag. Furthermore, reinforcing materials such as steel fiber can be mixed with the dry mortar to enhance the strength of the hardened mortar bag 3.

The amount of material filled into the bag-shaped body 3a should be 80-160% by weight, with loosely filled being 100%. Loose filling means allowing the material to fall naturally into the bag-shaped body 3a, and is a method commonly used to measure "loose bulk density." If the amount of material filled into the bag-shaped body 3a exceeds 160%, the strength will be good, but the mortar bag 3 will lose flexibility and will not conform to the slope N, resulting in additional material costs. Conversely, if the filling amount is below 80%, the mortar bag 3 will conform to the slope N well, but voids will form within the bag-shaped body 3a, and the hardening material will not integrate with the bag-shaped body 3a when hardening, resulting in a lack of solidity and strength (see Table 1 below).

For example, if the dry mortar 3b is made of a material with a cement:sand ratio of 1:2 (by weight), setting the filling amount to approximately 128% will result in a mortar bag 3 that is extremely excellent in terms of both strength and ability to conform to the slope N.

As shown in Figure 2, the bag-like body 3a constituting the mortar bag 3 has a double structure consisting of an inner bag body 6 and an outer bag body 7. A sheet of high-strength fiber 8 is disposed between these two bags 6, 7 to increase the longitudinal strength of the bag-like body 3a. The high-strength fiber 8 is used in at least the longitudinal direction of the bag-like body 3a, and this high-strength fiber 8 increases the longitudinal strength of the bag-like body 3a. The high-strength fiber 8 may be bonded (e.g., heat-sealed or adhesive) or connected (e.g., stitched) to one or both of the bags 6, 7, or simply inserted between the two bags 6, 7. The inner bag 6 may simply be inserted within the outer bag body 7, or may be bonded or connected to the outer bag 7 directly or indirectly via the high-strength fiber 8. If the inner bag 6 is simply inserted into the outer bag 7, for example, dry mortar 3b can be placed inside the inner bag 6, and then the outer bag 7 can be placed over the outside of the inner bag 6.

Here, the bags 6, 7 can be formed using a sheet-like material that is impermeable to the dry mortar 3b and has water or moisture permeability. Examples of materials for this include nonwoven fabric, felt, cloth (woven fabric), knitted fabric, jute cloth, hydrolytic plastic, and thin cotton.

The high-strength fibers 8 are made from synthetic fibers such as polyethylene, polyester, nylon, and vinylon, which are manufactured to be strong enough for industrial use, as well as high-strength glass fibers, carbon fibers, and aramid fibers.

The substrate bag 4 is a long, narrow, cylindrical bag-like body 4a with both ends closed, containing the substrate 4b. The bag-like body 4a can be formed using a water- or moisture-permeable sheet material that does not allow the substrate 4b to pass through. Its material can be the same as that of the bags 6 and 7. The substrate 4b can be a vegetation substrate containing, for example, vegetation seeds (plant seeds), growth aids (water-retaining materials, fertilizers, etc.), or soil conditioners, or it can be other conventional substrates, or even a mixture of vegetation substrates and conventional substrates. Examples of the vegetation substrate include a vermiculite-based mixture containing vegetation seeds, or a topsoil seed bank, specifically, a mixture of topsoil containing vegetation seeds from natural ground or forests near the slope protection area (revegetation area) with appropriate growth aids such as peat moss, bark compost, and water-retaining materials. This ensures that plants can be introduced in stripes. Furthermore, examples of the normal substrate include substrates appropriately selected from materials that do not harm vegetation, such as wood chips, agricultural and fishery waste (seashells, crab shells, fruit waste, etc.), and papermaking sludge.

The slope protection method of this embodiment is completed simply by laying the slope protection device 1 on the slope N, as shown in Figure 3(B). To lay the slope protection device 1, it is sufficient to secure the slope protection device 1 to the slope N by driving fixing members 9, such as anchor pins. It is also desirable to lay the slope protection device 1 so that each bag 3, 4 is aligned with the contour lines of the slope N, as this allows plants to take root in the soil accumulated on the mountain side of each bag 3, 4, creating the aforementioned berm effect that promotes earlier and more successful greening, and is also desirable from the perspective of improving the landscape. In addition to being placed on the contour lines, the mortar bags 3 can also be placed perpendicular to the contour lines, with fixing members 9 cast at the intersections to connect them in a grid pattern (not shown). This allows for a construction method that is more effective at protecting the slope N.

When the slope protection equipment 1 is laid on the slope N as described above, the bags 3 and 4 are positioned tightly against the slope N due to their own weight. In other words, the bags 3 and 4 are flexible enough to be stretched along the slope N even if it is uneven. The same applies to the net-like member 2.

As shown in Figure 3(B), the dry mortar 3b hardens as moisture is supplied to the mortar bag 3 by rainfall, etc. After the dry mortar 3b hardens, the mortar bag 3 maintains its shape, thereby maintaining the mortar bag 3 in close contact with the slope N. As a result, as shown in Figure 3(C), the eroded soil and sand accumulates on the mountain side of the mortar bag 3, reliably forming a vegetation base 10 and achieving the above-mentioned berm effect. In this example, as mentioned above, the amount of material filled into the bag-shaped body 3a is taken into consideration, so this berm effect can be achieved effectively and reliably.

In particular, by ensuring that multiple fixing members 9 penetrate a single mortar bag 3 when casting the fixing members 9, the mortar bag 3 is firmly connected to the head of the fixing member 9 after the dry mortar 3b hardens, forming an integrated structure. This reinforces the net-like member 2 both vertically and horizontally. This also enhances protection against deer trampling. The net-like member 2 in this example is fabricated using a Russell knitting (chain stitch) technique, which means its horizontal strength is weaker than its vertical strength, making it prone to lateral displacement (stretching). However, this lateral strength is significantly reinforced by the mortar bag 3 after the dry mortar 3b hardens. By firmly holding the slope N with the mortar bag 3, the stretchability of the net-like member 2 is limited, improving the protection of the surface of the slope N. In other words, simply by deploying the slope protection device 1 and securing it with the fixing members 9, the initial movement of boulders falling on the slope N can be effectively suppressed, preventing minor collapses caused by such movements. Therefore, the slope protection device 1 is suitable for use on slopes N prone to small rockfalls or erosion, and also helps to prevent frost heave on the slope N, making the slope protection method of this embodiment applicable as foundation work for greening (slope protection).

By implementing the slope protection method of laying the slope protection equipment 1 on the slope N as described above, the vegetation seeds in the base material 4b contained in the base material bag 4 will germinate and grow, allowing for more proactive greening. Even if the slope protection equipment 1 does not contain any plant seeds, the vegetation base 10 formed in a stepped pattern on the mountain side of the mortar bag 3 can effectively capture seeds that have drifted in from surrounding vegetation, allowing the plants to germinate and grow. This ensures that the slope N is reliably covered with greenery over almost the entire surface.

Moreover, the mortar formed from the dry mortar 3b in the mortar bag 3 has high compressive strength but low bending strength, which means the mortar is prone to cracking after hardening. However, the high-strength fibers 8, which increase the strength of the bag-shaped body 3a, make the mortar less likely to crack. Furthermore, even if the bag-shaped body 3a of the mortar bag 3 is too thick for water to penetrate sufficiently into the bag-shaped body 3a, or if the amount of water supplied to the mortar bag 3 is insufficient and the dry mortar 3b does not harden sufficiently, the bag-shaped body 3a can still retain its shape thanks to the high-strength fibers 8.

In addition, in the slope protection equipment 1 of this example, the high-strength fibers 8 are sandwiched between the inner bag body 6 and the outer bag body 7 in the bag-shaped body 3a of the mortar bag 3. This prevents the high-strength fibers 8 from peeling off when dry mortar 3b is placed in the mortar bag 3. In addition, the space formed within the three-layer structure of the bag-shaped body 3a improves the moisture retention capacity, and it is expected that the curing effect of the mortar will be improved (higher strength).

However, if the dry mortar 3b absorbs moisture and hardens before the slope protection device 1 is laid on the slope N, the bag-shaped body 3a may not adhere to the unevenness of the slope N after being laid on the slope N, and a sufficient berm effect may not be achieved. Therefore, in the slope protection device 1 of this example, as shown in Figures 1(A) and 3(A), a moisture-absorbing bag (drying bag) 13 containing a desiccant and having water or moisture permeability is attached to the net-shaped body 2. Specifically, a storage section 5a having a configuration similar to that of the storage section 5 is provided in the net-shaped body 2, and the moisture-absorbing bag 13 is stored in this storage section 5a.

Possible desiccants to be placed in the moisture absorption bag 13 include quicklime, silica gel, clay minerals such as bentonite, and calcium chloride. Each of these desiccants has its own characteristics, so they are usually used alone, but they may also be used in combination.

It is sufficient that at least one moisture absorption bag 13 is attached to one slope protection equipment 1 (net-like body 2). In the illustrated example, the moisture absorption bag 13 is attached to the end of the slope protection equipment 1 (net-like body 2), but the attachment position is not limited to this and it may also be in the center of the slope protection equipment 1 (net-like body 2), etc.

The moisture absorption bag 13 may be a long, thin tube with both ends closed, similar to the mortar bag 3 and the vegetation bag 4, with a length approximately equal to the width of the net-like body 2 (the length of the storage section 5a). However, if the moisture absorption bag 13 is made into a single, long, thin bag, uneven distribution of the desiccant contained therein becomes a problem. Therefore, in this example, to prevent or reduce uneven distribution of the desiccant, a desiccant is contained in each of multiple small bags (e.g., about 10 bags) connected in a strip. The amount of desiccant used, for example, quicklime, can be 10 to 120 g/ ^m² , preferably 20 to 40 g/ ^m² . In this case, 15 g of quicklime can be stored in each of the small bags (8 to 10 cm long).

The slope protection device 1 in this example is typically stored and distributed in a rolled state as shown in Figure 1(B) until it is laid on the slope N. The moisture-absorbing bag 13 attached to the device suppresses the hardening of the dry mortar 3b to some extent before the device is laid on the slope N. However, in order to prevent further hardening of the dry mortar 3b, it is preferable to minimize contact of the slope protection device 1 with the outside air containing moisture and humidity before laying it on the slope N. For example, it is possible to package the device in a moisture-proof film such as aluminum-vapor-deposited film or silica-vapor-deposited film, which has a high moisture-proofing effect. Moisture-proof film (thickness 120 μm) laminated with nylon or the like is relatively inexpensive and easy to use.

As shown in Figure 1(B), if the slope protection equipment 1 is placed inside a sealed bag 14 made of these moisture-proof films, and the opening of the sealed bag 14 is sealed using heat sealing or the like after removing as much air as possible, the bag-shaped body 3a (mortar 3) containing the dry mortar 3b and the moisture absorption bag 13 will be vacuum-packed.

If a desiccant is not used as described above, the dry mortar 3b may harden within a month, but if the moisture absorption bag 13 is used and the dry mortar 3b is vacuum-packed as described above, the dry mortar 3b can remain unhardened for more than six months.

Furthermore, while desiccants are generally discarded after they have fulfilled their purpose, in this example the moisture absorption bag 13 containing the desiccant is laid on the slope N while still attached to the net-like body 2. When quicklime is used as the desiccant, it has the effect of adjusting the soil pH and supplying the nutrient calcium. Silica gel supplies silicon, which is expected to have the effect of preventing grass plants from lodging. Furthermore, clay minerals such as bentonite have the ability to retain fertilizer in addition to water, so they can be expected to be effective in retaining fertilizer that would otherwise be washed away. Furthermore, not discarding the moisture absorption bag 13 containing the desiccant has the advantage of not generating waste at the construction site.

Furthermore, when packaging slope protection equipment 1 using vacuum packing, the volume of the slope protection equipment 1 itself is reduced by removing the air, which reduces transportation costs and makes storage space more compact. Furthermore, the hardening that accompanies vacuum packing also reduces the risk of collapse during transport, making the equipment easier to carry.

The present invention is not limited to the above-described embodiment, and can of course be implemented in various modifications without departing from the spirit of the present invention. For example, the following modifications can be mentioned:

When carrying out the slope protection method, the pre-integrated slope protection equipment 1 may be laid on the slope N. However, for example, the slope protection equipment 1 may be placed on the slope N without the bags 3, 4, and 13 attached, and then the bags 3, 4, and 13 may be inserted into the storage sections 5 and 5a. In this case, the slope protection equipment 1 is lighter, and can be transported to the slope N by a small number of people.

Furthermore, the bags 3, 4, and 13 are not limited to the elongated bag shape shown in Figure 1(A), but may be bags with approximately the same aspect ratio. In this case, the configuration of the storage sections 5, 5a of the net-like member 2 that hold the bags 3, 4, and 13 can be changed appropriately to suit the bags 3, 4, and 13.

A sheet-like member (not shown) made of biodegradable, soluble, or water-decomposable materials such as staple cotton, pulp fiber, or synthetic resin, and configured to allow water and plant sprouts and roots to pass through, may be attached to the underside of the net-like member 2 by any suitable means, such as by pasting. In this case, it is desirable to attach a vegetation substrate containing an appropriate selection of plant seeds, fertilizer, soil conditioner, or water-retaining material to the underside of the sheet-like member using a water-soluble adhesive, so that the sheet-like member supports the vegetation substrate. The sheet-like member can also be formed by thinly spreading rayon cotton.

The sheet-like member and net-like member 2 may be directly fixed together by adhesive bonding or the like. Alternatively, for example, the sheet-like member and net-like member 2 may be stacked on the slope N, and then anchor pins or other fixing members 9 may be driven into the slope N to lay them both down.

Furthermore, the material to which the bags 3, 4, and 13 are attached is not limited to the net-like material 2, but may be a mat-like or sheet-like material. Furthermore, using a net-like material 2 or the like can simplify the installation of the bags 3, 4, and 13, but this is not limiting, and it is also possible to install only the bags 3, 4, and 13.

In the examples shown in Figures 1(A) and 3(A), a storage section 5a for storing the moisture absorption bag 13 is provided separately from the storage section 5, but this is not limiting; the storage section 5a may not be provided and the moisture absorption bag 13 may be stored in the storage section 5. Also, while the net-like member 2 shown in Figure 1(A) is provided with storage sections 5, 5a, it is also possible to not provide the storage sections 5, 5a and instead tie the bags 3, 4, 13 to the net-like member 2 with rope, wire, etc., for example.

The slope protection method, which involves laying slope protection equipment 1, is suitable for use on slopes. Slope N is one example of a slope, but it goes without saying that the slope protection method can also be used on flat ground, for example. However, the slope protection method is more suitable for use on slope N because of the berm effect that can be achieved.

In the example shown in Figure 1 (A), one in three storage sections 5 contains a mortar bag 3, and the remaining storage sections 5 contain base material bags 4, but this is not limited to this. The ratio of mortar bags 3 and base material bags 4 can be changed as appropriate, such as storing a mortar bag 3 in one in two storage sections 5 and storing base material bags 4 in the remaining storage sections 5, or storing mortar bags 3 in all storage sections 5 without using base material bags 4.

In the above embodiment, a mortar bag 3 is used, in which dry mortar 3b is contained in a bag-shaped body 3a. However, this is not limited to this. For example, a bag (hardening bag) in which other hardening materials, such as gypsum or a cement-based material such as dry cement that does not contain aggregate, are contained in a bag-shaped body 3a may be used instead of the mortar bag 3.

The bag-like body 3a shown in Figure 2 has a three-layer structure, but this is not limiting. For example, the inner bag body 6 may be eliminated, leaving the high-strength fibers 8 exposed on the inside of the bag-like body 3a, or conversely, the outer bag body 7 may be eliminated, leaving the high-strength fibers 8 exposed on the outside of the bag-like body 3a.

A core material such as iron wire or high-strength fiber rope may be placed longitudinally inside the mortar bag 3, while maintaining the center with a spacer such as a lantern spacer (not shown). This increases the strength of the mortar bag 3, and may allow the bag-shaped body 3a to maintain good conformity to the slope N after the slope protection device 1 is laid on the slope N, until the dry mortar 3b in the mortar bag 3 hardens, and after it has hardened.

In the bag-shaped body 3a of the mortar bag 3 shown in Figure 2, high-strength fibers 8 are arranged in a tubular or bag-like shape that covers the outer surface of the inner bag body 6 and the entire inner surface of the outer bag body 7. However, this is not limited to this configuration; the high-strength fibers 8 may be configured to increase the longitudinal strength of the bag-shaped body 3a. For example, as shown in Figure 4(A), high-strength fibers 8 may be attached in a striped pattern to the sheet-shaped outer bag body 7, and as shown in Figure 4(B), the outer bag body 7 may be rolled into a tubular shape with the high-strength fibers 8 on the inside, and the edges may be closed to form the bag-shaped body 3a. The inner bag 6 may also be formed during this formation process, or the high-strength fibers 8 may be provided in the inner bag body 6 rather than the outer bag 7, and the inner bag body 6 may be rolled into a tubular shape with the high-strength fibers 8 on the outside. In either case, the high-strength fibers 8 have portions that extend longitudinally in the formed bag-shaped body 3a, thereby increasing the longitudinal strength of the bag-shaped body 3a.

In addition, in the modified example shown in Figures 4(A) and (B), the high-strength fibers 8 only have portions that extend in the longitudinal direction of the bag-shaped body 3a, but they may also have portions that extend in the circumferential direction of the bag-shaped body 3a. As an example, the high-strength fibers 8 may be arranged in a lattice pattern, as shown in Figures 5(A) and (B).

The high-strength fibers 8 can be arranged in a variety of ways as long as they can increase the longitudinal strength of the bag-shaped body 3a. For example, as shown in Figure 6(A), they can be arranged so that they run along the diagonal of the rectangular inner bag body 6 or outer bag body 7, or they can be arranged so that the high-strength fibers 8 extend spirally when the inner bag body 6 or outer bag body 7 is rolled into a cylindrical shape (see Figure 6(B)).

When mortar flows out of the mortar bag 3 due to the supply of moisture to the mortar bag 3 due to rainfall or other reasons, this mortar is alkaline and may have a negative impact on some vegetation. Therefore, taking into consideration that mortar will mainly flow out of the mortar bag 3 onto the valley side of the mortar bag 3, placing a neutralizing bag 11 on the valley side of the mortar bag 3, as shown in Figures 7, 8 (A), and (B), can reduce the negative impact of mortar flow on vegetation. To ensure this effect, when laying the slope protection equipment 1 on the slope N, it is preferable to position the slope protection equipment 1 so that the neutralizing bag 11 is located on the valley side of the mortar bag 3.

The neutralization bag 11 is a long, narrow, cylindrical bag 11a with both ends closed, containing an alkali neutralizer 11b. The bag 11a can be formed using a water- or moisture-permeable sheet that is impermeable to the alkali neutralizer 11b, and can be made from the same material as the bags 6 and 7. The alkali neutralizer 11b can be made from, for example, peat moss (acidic) or a carbonaceous material treated with acid (e.g., a material obtained by contacting hydrochloric acid with carbonized plant matter that has been carbonized after being exposed to a solution containing calcium chloride).

In the examples shown in Figures 7, 8(A), and 8(B), a mortar bag 3 and a neutralizing bag 11 are stored in the storage section 5 as a pair, and the neutralizing bag 11 to prevent mortar leakage is placed only on the valley side of the mortar bag 3. However, this is not limited to this, and the neutralizing bag 11 may also be placed on the mountain side of the mortar bag 3. Furthermore, the alkaline neutralizing agent 11b may be placed around the mortar bag 3 in a form other than the neutralizing bag 11.

To promote plant germination and growth in the vegetation base 10 (see Figure 3(C)) formed on the hillside of the mortar bag 3, a fertilizer bag 12 may be placed on the hillside of the mortar bag 3, as shown in Figure 9(A). In the illustrated example, a mortar bag 3 and a fertilizer bag 12 are stored as a pair in a single storage section 5. In this case, a substrate bag 4 can also be used instead of the fertilizer bag 12. Note that the fertilizer bag 12 can be, for example, a substrate bag 4 specifically designed to contain fertilizer.

Alternatively, a mortar bag 3, a neutralizing bag 11, and a base material bag 4 (or a fertilizer bag 12) may be stored in one storage section 5. In this case, it is preferable to place the neutralizing bag 11 on the valley side of the mortar bag 3 and the base material bag 4 (or a fertilizer bag 12) on the mountain side.

In the examples shown in Figures 7, 8(A), and 8(B), a single storage section 5 stores a mortar bag 3 and a neutralization bag 11, but this is not limited to this. For example, as shown in Figure 9(B), multiple storage sections 5 may be provided in series on the net-like member 2, with each storage section 5 storing a separate mortar bag 3 and neutralization bag 11. This also applies when fertilizer bags 12 are used instead of or in addition to the neutralization bags 11.

In the example shown in Figures 8(A) and (B), when the slope protection equipment 1 is laid on the slope N, the mortar bag 3 and the neutralizing bag 11 stored as a pair in one storage section 5 are individually pierced with the fixing members 9. However, of the mortar bags 3 and neutralizing bags 11, only the mortar bag 3 on the mountain side may be pierced and fixed with the fixing members 9. Note that, as shown in Figures 3(B) and (C), the mortar bags 3 stored individually in the storage section 5 are individually pierced and fixed to the slope N with the fixing members 9, and the base material bag 4 is fixed in the same way.

It goes without saying that the above modifications may be combined as appropriate.

Furthermore, in each of the above examples, high-strength fibers 8 are used to increase the longitudinal strength of the bag-shaped body 3a, but such high-strength fibers 8 do not necessarily have to be used.

REFERENCE SIGNS LIST 1 Slope protection equipment 2 Net-like member 3 Mortar bag 3a Bag-like body 3b Dry mortar 4 Base material bag 4a Bag-like body 4b Base material 5 Storage section 5a Storage section 6 Inner bag body 7 Outer bag body 8 High-strength fiber 9 Fixing member 10 Vegetation base 11 Neutralizing bag 11a Bag-like body 11b Alkaline neutralizer 12 Fertilizer bag 13 Moisture absorption bag N Slope

Claims (1)

A method for protecting a slope, comprising laying a bag-shaped body on a slope such as a slope, the bag-shaped body having a weight ratio of 80 to 160% of the weight of the contents contained therein when the content is loosely filled to 100%, the method comprising:
The bag-shaped body has a lattice-shaped high-strength fiber extending in the longitudinal and circumferential directions exposed on the outside of the bag body, and has flexibility to the extent that it can be stretched in a state that follows the unevenness of the surface of the slope of the greening target area,
The bag-like body and the net-like, mat-like or sheet-like member without the bag-like body attached are separately laid on the slope and integrated with each other,
A slope protection method characterized in that a bag-shaped body is fixed to the slope in a state where it is penetrated by a plurality of fixing members, thereby achieving a berm effect.