Inclined surface protection methods

Abstract

To provide a slope protection method that can reliably and effectively achieve the effect of small benches. [Solution] A slope protection method comprising laying a bag-shaped body 3a on a slope such as a slope N, wherein the amount of contents to be contained therein is 80-160% by weight when the rough-filled state is taken as 100%, the bag-shaped body is provided with a grid-like high-strength fibers 8 extending in the longitudinal and circumferential directions exposed on the inside of the bag-shaped body, and has enough flexibility to be stretched along the uneven surface of the slope of the area to be greened, and the bag-shaped body and a net-like, mat-like, or sheet-like member 2 without the bag-shaped body attached are integrated in advance before being laid on the slope, and the bag-shaped body is fixed to the slope by being penetrated by a plurality of fixing members 9 to obtain a bench effect.

Description

Technical Field

[0001] The present invention relates to a slope protection method for protecting slopes such as road cut slopes, for example.

Background Art

[0002] There is known a slope protection work in which a slope protection tool composed of a bag-shaped body containing a base material together with vegetation seeds (seeds of plants for greening) and a net-shaped member to which a plurality of these bag-shaped bodies are attached is installed on a road cut slope (slope) (Patent Document 1).

[0003] In this slope protection work, a vegetation base is formed in a step shape on the mountain side of the bag-shaped body by the washed-away sediment dammed up by the bag-shaped body and the fallen leaves from the surroundings, etc., and greening is achieved early and favorably by the so-called step effect in which plants can grow easily in this step. That is, the step effect referred to here means an effect in which a growth base layer having a gentler gradient than the road cut slope is formed in a step shape due to the deposition of sediment, and plants can grow easily in this step.

[0004] However, the base material in the bag-shaped body used in this slope protection work is mainly composed of organic matter and vermiculite, and the organic matter is consumed or the vermiculite shrinks over time, and in some construction environments, severe shrinkage of the base material may occur. And in this case, along with this shrinkage, the vegetation base constituting the step slides or slips off from the gap generated between the road cut slope and the bag-shaped body of the slope protection tool installed on this road cut slope or from the upper side of the bag-shaped body, and the vegetation base is not formed on the mountain side of the bag-shaped body, and as a result, there is a problem that the step effect cannot be obtained.

[0005] Therefore, it is conceivable to include a curing material that cures by absorbing water in the base material or the bag-shaped body. If the curing material cures due to rainfall or the like, the shape of the bag-shaped body is maintained, so that it is possible to prevent the loss of the step effect.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2007-56606 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, the conventional slope protection equipment described above may not provide sufficient edge protection.

[0008] The present invention has been made with the above-mentioned matters in mind, and its purpose is to provide a slope protection method that can obtain a good and reliable bench effect. [Means for solving the problem]

[0009] To achieve the above objective, the slope protection method according to the present invention is a slope protection method that involves laying a bag-shaped body on a slope such as an embankment, wherein the amount of contents contained therein is 80 to 160% by weight when the rough-filled state is taken as 100%, the bag-shaped body is provided with a grid-like high-strength fiber extending in the longitudinal and circumferential directions exposed on the inside of the bag-shaped body, has sufficient flexibility to be stretched along the uneven surface of the slope of the area to be greened, the bag-shaped body and a net-like, mat-like, or sheet-like member without the bag-shaped body attached are integrated in advance before being laid on the slope, and the bag-shaped body is fixed to the slope by being penetrated by a plurality of fixing members to obtain a bench effect (Claim 1). [Effects of the Invention]

[0010] The present invention provides a slope protection method that can reliably and effectively achieve a small-bench effect. [Brief explanation of the drawing]

[0011] [Figure 1] (A) is a schematic perspective view showing the configuration of a slope protection tool used in a slope protection method according to one embodiment of the present invention in an unfolded state, and (B) is an explanatory diagram showing a method for storing the slope protection tool. [Figure 2]This is an explanatory diagram illustrating the structure of the bag-shaped body of the mortar bag used as the slope protection device. [Figure 3] (A) is a longitudinal cross-sectional view schematically showing the installation state of the slope protection device, and (B) and (C) are explanatory diagrams schematically showing the changes in the state of the slope protection device laid on the slope. [Figure 4] (A) and (B) are explanatory diagrams that schematically show the structure of modified bags before and after formation. [Figure 5] (A) and (B) are schematic diagrams illustrating the structure of other modified versions of the bag-like body before and after formation. [Figure 6] (A) and (B) are explanatory diagrams that schematically show the configuration of yet another modified example of the bag-like body. [Figure 7] This is an explanatory diagram illustrating the configuration of another modified example of the aforementioned slope protection device. [Figure 8] (A) and (B) are explanatory diagrams that schematically show the changes in the condition of the slope protection equipment shown in Figure 7, which is laid on the slope. [Figure 9] (A) and (B) are explanatory diagrams that schematically show the configuration of modified examples of the slope protection device. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described below with reference to the drawings.

[0013] 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, in order to protect and green the slope N.

[0014] As shown in Figure 1(A), the slope protection device 1 comprises a net-like member 2 having a roughly rectangular shape, and a mortar bag 3 and a base material bag 4 that are held (attached) to this net-like member 2.

[0015] The net-shaped member 2 has accommodation portions 5 at appropriate intervals in the longitudinal direction. Here, the net-shaped member 2 in this example is a member with a width of, for example, 1 m and a vertical length of 5 to 10 m, and the accommodation portions 5 are provided at intervals of 30 cm in the vertical direction. That is, in Fig. 1(A), only a part of the net-shaped member 2 (the slope protection tool 1) is shown. And in each accommodation portion 5, a mortar bag 3 or a base material bag 4 is individually accommodated. In the example shown in Fig. 1(A) and Fig. 3(A), one mortar bag 3 is accommodated in every three accommodation portions 5, and the base material bags 4 are accommodated in the remaining accommodation portions 5. Note that the accommodation portion 5 is formed in a bag shape, a cylindrical shape or a pocket shape with a size capable of accommodating the mortar bag 3 or the base material bag 4, and each bag 3, 4 is inserted into the inside thereof from one end side of the accommodation portion 5, whereby each bag 3, 4 is held by the net-shaped member 2.

[0016] Note that the net-shaped member 2 is formed by using fibers rich in durability (such as fibers of nylon, polyester, aramid, carbon, glass, polyacetal, etc.) or corrosive fibers (such as fibers of coconut, etc.) to a mesh size of about 5 to 10 mm, and these two types (fibers rich in durability and corrosive fibers) may be overlapped. Further, in order to improve the strength, a wire mesh (such as a hexagonal wire mesh or a lath wire mesh) may be overlapped on the net-shaped member 2.

[0017] As shown in Fig. 1(A), the mortar bag 3 is a bag-like body 3a with an elongated cylindrical shape having both ends closed and having water permeability or moisture permeability, and contains a dry mortar (an example of a curing material) 3b that cures by absorbing water. Since it does not contain materials that cause voids in the bag-like body 3a (such as materials like a base material that gradually decreases in porosity over time due to elution of fertilizer components, etc.), high strength can be achieved. The dry mortar 3b in this example is obtained by mixing cement with granular sand as an aggregate, but the aggregate constituting the dry mortar 3b is not limited to sand, and vermiculite, perlite (pumice), etc. can also be used. The contents contained in the bag-like body 3a can be made into a cured bag with high strength by containing only the curing material that cures by absorbing water or moisture, or by mixing the curing material only with the aggregate. Further, a reinforcing material such as steel fiber may be mixed into the dry mortar so as to obtain an effect of improving the strength of the mortar bag 3 after curing.

[0018] Here, the filling amount of the contents with respect to the bag-like body 3a is set to be 80 - 160% by weight when the rough filling is 100%. Rough filling means filling the contents into the bag-like body 3a by natural dropping, and is a method generally used when measuring the "loose bulk density". When the filling amount of the contents with respect to the bag-like body 3a exceeds 160%, although it is good in terms of strength, the flexibility of the mortar bag 3 is lost and it becomes difficult to follow the slope N, and an extra material cost is also required. On the contrary, when the filling amount is less than 80%, the adaptability of the mortar bag 3 to the slope N becomes good, but voids occur in the bag-like body 3a, and a dense cured body cannot be obtained due to reasons such as not integrating with the bag-like body 3a during the curing of the curing material, resulting in insufficient strength (see Table 1 below).

[0019]

Table 1

[0020] For example, if a material with a cement:sand ratio of 1:2 (by weight) is used as dry mortar 3b, then by making the above filling amount approximately 128%, a mortar bag 3 with excellent strength and conformability to slope N can be obtained.

[0021] Furthermore, 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, and a sheet-like high-strength fiber 8 is placed between these two bag bodies 6 and 7 to increase the longitudinal strength of the bag-like body 3a. Here, 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 joined (e.g., heat-sealed or bonded) or connected (e.g., sutured) to either one or both of the bag bodies 6 and 7, or it may simply be inserted between the two 6 and 7. On the other hand, the inner bag body 6 may simply be inserted into the outer bag body 7, or it may be joined or connected to the outer bag body 7 directly or indirectly via the high-strength fiber 8, for example. If the inner bag 6 is simply inserted into the outer bag 7, for example, after filling the inner bag 6 with dry mortar 3b, the outer bag 7 can be placed over the outside of the inner bag 6.

[0022] Here, the bags 6 and 7 can be formed using a sheet-like material that does not allow the dry mortar 3b to pass through and is permeable to water or moisture. Examples of such materials include nonwoven fabric, felt, cloth (woven fabric), knitted fabric, jute cloth, water-degradable plastic, and thin cotton.

[0023] Furthermore, the materials used for the high-strength fiber 8 include synthetic fibers such as polyethylene, polyester, nylon, and vinylon, which are manufactured to be highly strong for industrial use, as well as high-strength glass fibers, carbon fibers, and aramid fibers.

[0024] The base material bag 4 contains the base material 4b in a bag-like body 4a that is elongated and cylindrical with both ends closed. The bag-like body 4a can be formed using a sheet-like material that is permeable to water or moisture but does not allow the base material 4b to pass through, and the same material as the bags 6 and 7 can be used for the bag-like body 4a. The base material 4b may be a vegetation base material containing, for example, seeds of plants for greening (vegetation seeds), growth aids (water-retaining materials, fertilizers, etc.), or soil conditioners, as appropriately selected from these, or it may be another ordinary base material, or it may be a mixture of the vegetation base material and the ordinary base material. Examples of the vegetation base material include one that is mainly composed of vermiculite and contains vegetation seeds, or one that contains a topsoil seed bank, and specifically, one that is made by appropriately mixing topsoil containing vegetation seeds from the natural ground or forest near the slope protection area (greening area) with growth aids such as peat moss, bark compost, and water-retaining materials. In this case, plants can be reliably introduced in a linear fashion. Furthermore, the aforementioned conventional base materials include base materials appropriately selected from materials that do not harm vegetation, such as wood chips, agricultural and marine waste (seashells, crab shells, fruit scraps, etc.), and papermaking sludge.

[0025] Furthermore, 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 fix it to the slope N by, for example, driving in fixing members 9 such as anchor pins. It is also desirable to lay the slope protection device 1 on the slope N so that each bag 3, 4 is aligned with the contour lines, as this allows plants to take root in the soil accumulated on the uphill side of each bag 3, 4, thereby achieving the aforementioned terrace effect, which enables earlier and better greening, and is also desirable in terms of improving the landscape. In addition to arranging the mortar bags 3 along the contour lines, they may also be arranged perpendicular to the contour lines and connected in a grid pattern by driving in fixing members 9 at the intersections (not shown). Doing so can result in a construction method that provides a higher level of protection for the slope N.

[0026] As described above, each bag 3 and 4 of the slope protection device 1 laid on the slope N is positioned along the slope N without any gaps due to its own weight. In other words, each bag 3 and 4 has enough flexibility to be stretched along the slope N even if there are irregularities. The same applies to the net-like member 2.

[0027] Then, 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 in this way, the mortar bag 3 maintains its shape, and thus maintains its close contact with the slope N. As shown in Figure 3(C), runoff sediment accumulates on the uphill side of the mortar bag 3, ensuring the formation of a vegetation base 10 and obtaining the aforementioned terrace effect. Furthermore, in this example, as described above, the amount of contents to be filled into the bag-like body 3a is taken into consideration, so such a terrace effect can be obtained well and reliably.

[0028] In particular, when installing the fixing member 9, by ensuring that one mortar bag 3 is pierced by multiple fixing members 9, after the dry mortar 3b hardens, the mortar bag 3 is firmly connected to the head of the fixing member 9, forming an integrated structure, thus providing a reinforcing effect on the net-like member 2 in both the longitudinal and transverse directions. In this case, the protective effect against deer trampling is also enhanced. Here, the net-like member 2 in this example is obtained by Russell weaving (chain weaving), and its strength in the transverse direction is inferior to its strength in the transverse direction, making it prone to shifting (stretching) in the transverse direction. However, this transverse strength is greatly reinforced by the mortar bag 3 after the dry mortar 3b hardens, and by firmly pressing the slope N with the mortar bag 3, the elasticity of the net-like member 2 is restricted, improving the protective function of the surface of the slope N. In other words, by simply deploying the slope protection device 1 and fixing it with the fixing member 9, the initial movement of falling rocks on the slope N can be effectively suppressed, and the resulting small collapses can be prevented. Therefore, the slope protection device 1 is suitable for use on slopes N that are prone to small rockfalls and slopes N that are prone to erosion, and it also contributes to suppressing frost heave on slopes N, making the slope protection method of this embodiment applicable as a greening (slope protection) foundation.

[0029] As described above, by implementing the slope protection method in which the slope protection device 1 is laid on the slope N, the vegetation seeds contained in the base material 4b within the base material bag 4 will germinate and grow, enabling more active greening. Furthermore, even if the slope protection device 1 does not contain plant seeds, the vegetation base 10 formed in a step-like manner on the uphill side of the mortar bag 3 can effectively capture seeds blown in from the surrounding vegetation, allowing plants to germinate and grow. Therefore, greening of almost the entire surface of the slope N will be reliably achieved.

[0030] Furthermore, while the mortar formed by the dry mortar 3b in the mortar bag 3 has high compressive strength, its flexural strength is low, and therefore the mortar is prone to cracking after hardening. However, the high-strength fibers 8, which increase the strength of the bag-like body 3a, make the mortar less prone to cracking. In addition, even if the bag-like body 3a of the mortar bag 3 is thick and water does not penetrate sufficiently into the inside of the bag-like 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-like body 3a can maintain its shape due to the high-strength fibers 8.

[0031] Furthermore, in the slope protection device 1 of this example, the high-strength fibers 8 are sandwiched between the inner bag 6 and the outer bag 7 in the bag-like 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, and also increases the moisture retention performance by creating a space within the three-layer structure of the bag-like body 3a, which can be expected to enhance the curing effect of the mortar (increase in strength).

[0032] By the way, if the dry mortar 3b has absorbed moisture and hardened before the slope protection device 1 is laid on the slope N, the bag-shaped body 3a may not adhere closely to the unevenness of the slope N after being laid on the slope N, and a sufficient bench effect may not be obtained. 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 permeability or moisture permeability is attached to the net-shaped body 2. Specifically, the net-shaped body 2 is provided with a housing section 5a having the same configuration as the housing section 5, and the moisture-absorbing bag 13 is housed in this housing section 5a.

[0033] Suitable desiccants to be placed in the moisture-absorbing bag 13 include quicklime, silica gel, clay minerals such as bentonite, and calcium chloride. Each of these desiccants has its own properties, so they are usually used individually, but they may also be used in mixtures.

[0034] Furthermore, it is sufficient for at least one moisture-absorbing bag 13 to be attached to each slope protection device 1 (net-like body 2). In the illustrated example, the moisture-absorbing bag 13 is attached to the end of the slope protection device 1 (net-like body 2), but the attachment position is not limited to this, and it may also be attached to the center of the slope protection device 1 (net-like body 2), etc.

[0035] As the moisture-absorbing bag 13, a long, narrow cylindrical shape with both ends closed, similar to the mortar bag 3 and vegetation bag 4, may be used, with a length approximately equal to the width of the net-like body 2 (length of the containment section 5a). However, if the moisture-absorbing bag 13 is a single long, narrow bag, uneven distribution of the desiccant inside becomes a problem. Therefore, in this example, to prevent and reduce uneven distribution of the desiccant, the desiccant is contained in multiple small bags (for example, about 10 bags) connected in a strip. The amount of desiccant used, taking quicklime as an example, is 10-120 g / m². 2 Preferably 20-40 g / m 2 This can be done, and in this case, quicklime can be divided into 15g portions and placed in the above-mentioned small bags (bag length 8-10cm).

[0036] In this example, the slope protection device 1 is typically stored and distributed in a rolled state, as shown in Figure 1(B), until it is laid on the slope N. The presence of a moisture-absorbing bag 13 helps to some extent to suppress the hardening of the dry mortar 3b until the slope protection device 1 is laid on the slope N. However, to further prevent the hardening of the dry mortar 3b, it is preferable to minimize contact between the slope protection device 1 and the outside air containing moisture and humidity before laying it on the slope N. For example, it is possible to pack it in a moisture-proof film such as an aluminum vapor-deposited film or a silica vapor-deposited film, which has a high moisture-proof effect. A moisture-proof film (120 μm thick) made of laminated nylon is relatively inexpensive and easy to use.

[0037] Furthermore, as shown in Figure 1(B), if the slope protection device 1 is placed inside the sealed bag 14 made of these moisture-proof films, and the opening of the sealed bag 14 is sealed with heat sealing or the like while removing as much air as possible, the bag-like body 3a (mortar 3) containing the dry mortar 3b and the moisture-absorbing bag 13 will be in a vacuum-sealed state.

[0038] As described above, if a desiccant is not used, the dry mortar 3b may harden within one month. However, if a moisture-absorbing bag 13 is used and vacuum-packed as described above, the dry mortar 3b can remain soft for more than six months.

[0039] Furthermore, while desiccants are generally discarded after fulfilling their purpose, in this example, the moisture-absorbing bag 13 containing the desiccant is laid on the slope N while still attached to the net-like structure 2. If quicklime is used as the desiccant, it has the effect of adjusting the soil pH and supplying calcium, a nutrient. Silica gel supplies silicon, and is expected to have the effect of suppressing lodging of grasses. Clay minerals such as bentonite have water retention and nutrient retention capabilities, so they are expected to retain nutrients that would otherwise be washed away. Moreover, not discarding the moisture-absorbing bag 13 containing the desiccant has the advantage of not generating waste at the construction site.

[0040] Furthermore, when vacuum-packing the slope protection device 1, removing the air reduces the volume of the device itself, which can lower transportation costs and reduce storage space. Additionally, the hardening effect of vacuum packing makes it less likely for the package to collapse during transport, making it easier to carry.

[0041] It should be noted that the present invention is not limited in any way to the embodiments described above, and can be implemented in various ways without departing from the spirit of the invention. For example, the following modifications can be given.

[0042] When implementing the aforementioned slope protection method, the integrated slope protection device 1 may be laid on the slope N beforehand. Alternatively, for example, the slope protection device 1 without the bags 3, 4, and 13 attached may be placed on the slope N, and then the bags 3, 4, and 13 may be inserted into the storage compartments 5, 5a. In this case, the slope protection device 1 is lighter, and it can be transported to the slope N by fewer people.

[0043] Furthermore, each bag 3, 4, and 13 is not limited to being an elongated bag shape as shown in Figure 1(A), but may also be a bag shape with approximately the same length-to-width ratio. In this case, the configuration of the housing sections 5 and 5a of the net-like member 2 that holds each bag 3, 4, and 13 can also be appropriately changed to match each bag 3, 4, and 13.

[0044] A sheet-like member (not shown), formed from a biodegradable, soluble, or hydrolytic material such as thin rayon fiber, pulp fiber, or synthetic resin, and configured to allow water and plant buds and roots to pass through, may be attached to the underside of the net-like member 2 by appropriate means such as adhesion. In this case, it is desirable to attach a vegetation base material containing vegetation seeds, fertilizer, soil conditioner, water-retaining material, etc., to the underside of the sheet-like member using a water-soluble adhesive, so that the sheet-like member supports the vegetation base material. The sheet-like member can also be formed by thinly rolling out thin rayon fiber.

[0045] While the sheet-like member and the net-like member 2 may be directly fixed by adhesive or other means, for example, the sheet-like member and the net-like member 2 may be laid on the slope N in a stacked state, and then fixed members 9 such as anchor pins may be driven in to secure them to the slope N.

[0046] Furthermore, the member to which each bag 3, 4, and 13 is attached is not limited to the net-like member 2, but may also be a mat-like or sheet-like member. Also, while using the net-like member 2, etc., can simplify the installation of each bag 3, 4, and 13, the system is not limited to this, and each bag 3, 4, and 13 may be installed separately.

[0047] In the examples shown in Figures 1(A) and 3(A), a storage section 5a for housing the moisture-absorbing bags 13 is provided separately from the storage section 5. However, the design is not limited to this, and the moisture-absorbing bags 13 may be housed in the storage section 5 without providing a storage section 5a. Also, although the net-like member 2 shown in Figure 1(A) is provided with storage sections 5 and 5a, the bags 3, 4, and 13 may be tied to the net-like member 2, for example, with rope or wire, without providing storage sections 5 and 5a.

[0048] The slope protection method, which involves laying the slope protection device 1, is suitable for implementation on slopes. While slope N is an example of a slope, it goes without saying that the slope protection method may also be implemented on flat ground, for example. However, the slope protection method is more suitable for implementation on slope N, as it provides the aforementioned bench effect.

[0049] In the example shown in Figure 1(A), mortar bags 3 are stored in one-third of the storage compartments 5, and base material bags 4 are stored in the remaining storage compartments 5. However, the ratio of mortar bags 3 and base material bags 4 can be changed as appropriate. For example, mortar bags 3 may be stored in one-half of the storage compartments 5, and base material bags 4 may be stored in the remaining storage compartments 5, or mortar bags 3 may be stored in all storage compartments 5 without using base material bags 4.

[0050] In the above embodiment, a mortar bag 3 containing dry mortar 3b in a bag-like body 3a is used. However, the invention is not limited to this, and a bag (hardening bag) containing other hardening materials such as cement-based materials like dry cement without aggregate or gypsum in a bag-like body 3a may be used instead of the mortar bag 3.

[0051] The bag-like body 3a shown in Figure 2 has a three-layer structure, but it is not limited to this. For example, the inner bag 6 may be omitted so that the high-strength fibers 8 are exposed on the inside of the bag-like body 3a, or conversely, the outer bag 7 may be omitted so that the high-strength fibers 8 are exposed on the outside of the bag-like body 3a.

[0052] A core material such as iron wire or high-strength fiber rope may be placed in the longitudinal direction inside the mortar bag 3, with spacers such as lantern spacers to maintain the center (not shown). This can result in a stronger mortar bag 3, and allow the bag-like body 3a to maintain a good conformity to the slope N after the slope protection device 1 is laid on the slope N, both during the period before the dry mortar 3b in the mortar bag 3 hardens and after hardening.

[0053] In the mortar bag 3 shown in Figure 2, the bag-like body 3a is provided with high-strength fibers 8 in a cylindrical or bag-like shape that covers the entire outer surface of the inner bag 6 and the inner surface of the outer bag 7. However, the high-strength fibers 8 are not limited to this configuration and should be configured to increase the strength of the bag-like body 3a in the longitudinal direction. Therefore, for example, as shown in Figure 4(A), the high-strength fibers 8 may be fixed in a striped pattern to a sheet-like outer bag 7, and as shown in Figure 4(B), the outer bag 7 may be rolled into a cylindrical shape so that the high-strength fibers 8 are on the inside, and its edges may be closed to form the bag-like body 3a. The inner bag 6 may be provided during this formation process, or the high-strength fibers 8 may be provided in the inner bag 6 instead of the outer bag 7, and the inner bag 6 may be rolled into a cylindrical shape so that the high-strength fibers 8 are on the outside. In any case, in the formed bag-like body 3a, the high-strength fibers 8 have portions that extend in the longitudinal direction of the bag-like body 3a, so the strength of the bag-like body 3a in the longitudinal direction is increased.

[0054] Furthermore, in the modified examples shown in Figures 4(A) and (B), the high-strength fibers 8 only have portions that extend in the longitudinal direction of the bag-like body 3a, but they may also have portions that extend in the circumferential direction of the bag-like body 3a. For example, as shown in Figures 5(A) and (B), the high-strength fibers 8 can be arranged in a lattice pattern.

[0055] Furthermore, the high-strength fibers 8 can be provided in various ways within a range that increases the longitudinal strength of the bag-like body 3a. For example, as shown in Figure 6(A), they may be provided so as to pass along the diagonals of the rectangular inner bag 6 or outer bag 7, or they may be provided so that the high-strength fibers 8 extend in a spiral when the inner bag 6 or outer bag 7 is rolled into a cylindrical shape (see Figure 6(B)).

[0056] When mortar bags 3 are supplied with moisture due to rainfall, etc., mortar may flow out of the bags 3. This mortar is alkaline and may have adverse effects on vegetation. Therefore, considering that mortar mainly flows out from the bags 3 towards the valley side of the bags 3, as shown in Figures 7, 8(A) and (B), placing the neutralizing bag 11 on the valley side of the bags 3 can suppress adverse effects on vegetation due to mortar runoff. To ensure that this effect is obtained, it is preferable to position the slope protection device 1 on the slope N so that the neutralizing bag 11 is located on the valley side of the bags 3.

[0057] The neutralizing bag 11 is a bag-like body 11a that is elongated and cylindrical with both ends closed, containing an alkali neutralizing agent 11b. The bag-like body 11a can be formed using a sheet-like material that is impermeable to water or moisture but does not allow the alkali neutralizing agent 11b to pass through, and the same material as that used for bags 6 and 7 can be used for the bag-like body 11a. For the alkali neutralizing agent 11b, for example, peat moss (acidic) or an acid-treated carbon material (for example, a material obtained by contacting a carbonized plant material, which has been carbonized after contact with a solution containing calcium chloride, with hydrochloric acid) can be used.

[0058] In the examples shown in Figures 7, 8(A), and 8(B), the mortar bag 3 and the neutralizing bag 11 are housed together in the storage section 5, and the neutralizing bag 11 for preventing mortar outflow is placed only on the valley side of the mortar bag 3. However, the design is not limited to this, and the neutralizing bag 11 may also be placed on the mountain side of the mortar bag 3, or the alkaline neutralizing agent 11b may be placed around the mortar bag 3 in a form other than the neutralizing bag 11.

[0059] To promote plant germination and growth in the vegetation base 10 (see Figure 3(C)) formed on the raised side of the mortar bag 3, a fertilizer bag 12 may be placed on the raised side of the mortar bag 3, as shown in Figure 9(A). In the illustrated example, the mortar bag 3 and the fertilizer bag 12 are housed together in one storage compartment 5. In this case, a base material bag 4 can also be used instead of the fertilizer bag 12. The fertilizer bag 12 can be, for example, a base material bag 4 specifically designed for fertilizer.

[0060] Alternatively, the mortar bag 3, neutralizing bag 11, and base material bag 4 (or fertilizer bag 12) may be housed in a single storage compartment 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 fertilizer bag 12) on the mountain side.

[0061] Furthermore, in the examples shown in Figures 7, 8(A), and (B), the mortar bag 3 and neutralization bag 11 are housed in a single storage compartment 5. However, the design is not limited to this, and for example, as shown in Figure 9(B), multiple storage compartments 5 may be arranged in a continuous line on the net-like member 2, with the mortar bag 3 and neutralization bag 11 housed individually in each storage compartment 5. The same applies when a fertilizer bag 12 is used instead of, or in addition to, the neutralization bag 11.

[0062] In the examples shown in Figures 8(A) and (B), when laying the slope protection device 1 on the slope N, the mortar bags 3 and neutralization bags 11, which are housed in pairs in one housing section 5, are individually pierced by the fixing member 9. However, it is also possible to pierce and fix only the mortar bag 3 on the mountain side of the mortar bag 3 and neutralization bag 11 with the fixing member 9. As shown in Figures 3(B) and (C), the mortar bags 3 housed individually in the housing section 5 are individually pierced by the fixing member 9 and fixed to the slope N, and the base material bags 4 are fixed in the same manner.

[0063] Needless to say, the above variations can be combined as appropriate.

[0064] Furthermore, in each of the above examples, the strength of the bag-like body 3a in the longitudinal direction is increased by the high-strength fibers 8, but it is not necessary to use such high-strength fibers 8. [Explanation of symbols]

[0065] 1. Slope protection equipment 2 Net-like member 3 mortar bags 3a pouch-like body 3b Dry mortar 4 Base material bag 4a pouch-like body 4b Base material 5. Storage Area 5a Storage area 6. Inner bag 7. Outer bag 8. High-strength fibers 9 Fixing member 10 Vegetation base 11 Neutralization bag 11a Bag-like body 11b Alkaline neutralizing agent 12 Fertilizer bag 13 Moisture-absorbing bags N slope

Claims

[Claim 1] A slope protection method in which bag-shaped bodies are laid on slopes such as embankments, wherein the amount of contents to be contained therein is 80 to 160% by weight when the rough-filled state is considered 100%, The bag-like body is provided with a grid of high-strength fibers extending in the longitudinal and circumferential directions exposed on the inside of the bag, and has enough flexibility to be stretched along the uneven surface of the slope of the area to be greened. The bag-like body and the net-like, mat-like, or sheet-like member without the bag-like body are pre-integrated before being laid on the slope. A slope protection method characterized by obtaining a bench effect by fixing a bag-like body to a slope in a state where it is penetrated by multiple fixing members.

Images