JP5414554B2 - Greening sheet manufacturing method and slope greening method - Google Patents

Description

  The present invention relates to a method for manufacturing a greening sheet used for slope greening and the like, and a method for greening a slope by applying the greening sheet manufactured by this manufacturing method.

  When creating a slope by embankment, in order to prevent the slope from collapsing, a mesh-like reinforcing material called a tensor is laid in layers in the embankment, and a steel frame and a sheet for preventing soil erosion are sloped. Geotextile construction method is often used. In this geotextile construction method, a sheet for preventing soil erosion made of turfgrass seeds is attached to the back of the steel frame to prevent soil runoff and collapse from the slope while greening the slope. Is.

  In order to explain the geotextile construction method in more detail, on the back of the steel frame used in the construction method, a vegetation sheet in which seeds of plants such as turfgrass are knitted on a sheet for preventing soil erosion composed of a nonwoven fabric or the like Is generally laid. However, it takes time for the turfgrass seeds to germinate and for the turf to penetrate the vegetation sheet and settle on the embankment slope. Since it is easy to be affected by the amount of water and its change, it is difficult to make a uniform greening of the slope with turf grass at present, and it is hard to say that it is sufficient to prevent the prevention of sediment runoff and slope collapse from the slope.

  By the way, the applicant, etc., laid a steel frame with a grass grass mat and a soil erosion prevention sheet fixed to the slope with a steel frame when greening the construction slope with a geotextile method at a certain construction site. Trying to do. However, since the turfgrass mat is formed only from the intertwined stalks, it is easy to collapse during construction, and it has been found that it takes a lot of trouble to fix the slope. In addition, it is difficult to make the turf evenly contact with the vegetation sheet or the slope by simply fixing it with a wire or the like, and the turf tends to wither due to this, so it takes a period until the turf takes root. It was also found that frequent watering is essential.

  Here, to turn to the conventional public technique that uses turfgrass to greenen the slope of construction, Patent Document 1 discloses that the slope erosion prevention sheet and the vegetation turf sheet are integrated on the field. A method for producing a vegetation sheet for slope protection is disclosed.

  In particular, in the composite sheet (product B) shown in FIG. 2, the composite sheet is obtained by cutting out with the turf root attached to the field soil. The product weight is extremely heavy. For example, when it is used for slope planting in which the above-mentioned geotextile method is applied, it is inevitable that laying on the slope is difficult due to the weight.

  Therefore, when trying to cut out the composite sheet directly under the erosion prevention sheet in order to reduce the product weight, this time, most of the turf that has entered the soil of the field will be cut off from the sheet, For example, turf roots cannot be rooted on steep slopes where geotextile methods are applied.

  On the other hand, as another disclosed technique, Patent Document 2 discloses that a net material is developed on a water-impermeable flat base, and a lawn mat, lawn runner, seeds, etc. are spread on the net material to integrate the net material and the lawn. A method for achieving this is disclosed.

  In this technology, net material is used for the production of vegetation mats. However, even if a net-like material is applied to a steep slope, for example, a geotextile method is applied, it prevents slope erosion and its collapse. It is extremely difficult.

  Therefore, instead of the net material, for example, when a sheet made of nonwoven fabric is applied to the technique disclosed in Patent Document 2 to produce a vegetation mat, this time, the sheet is placed on an impermeable flat ground. Since it is unfolded, the turf root does not penetrate the sheet and forms a mat-like root system on the sheet-like surface. And if you try to lay this on the slope as it is, the root system of the mat-like turf will retain moisture, so it will take a lot of time to root in the soil that constitutes the slope, It is still susceptible to the weather conditions and changes described above, and it is difficult to uniformly green the slope.

  Furthermore, in Patent Document 2, there is a description that when a grass root and a net material are entangled with each other, a water retention base material is provided by bark compost or the like, and a vegetation mat is manufactured with a high water retention base. Although ease of peeling off the vegetation mat is guaranteed, it is difficult to reduce the weight of the vegetation mat because it contains a water-retaining base material. .

JP 2000-282473 A JP 2002-105962 A

  The present invention has been made in view of the above-described problems, and has a good lawn rooting with respect to the construction slope and is easy to settle. Therefore, the slope of the slope is as uniform as possible in as short a period as possible. Even if this slope has a steep slope, it can effectively prevent slope erosion and its collapse, and can be used to realize slope planting construction with excellent workability. It aims at providing the manufacturing method of a greening sheet, and the slope greening method which applied the greening sheet manufactured by this manufacturing method.

  In order to achieve the above object, a method for producing a greening sheet according to the present invention includes laying a sheet for preventing soil erosion on a water-permeable artificial ground, growing grass on the sheet, and starting from above the sheet. A greening sheet in which the turf root penetrates and the sheet and the grass are integrated is formed on the artificial ground, and the greening sheet is separated from the artificial ground to obtain a greening sheet.

  Here, “permeable artificial ground” means that crushed rocks such as volcanic gravel, coarse sand, boulder gravel, gravel, crusher run, etc. are spread in cultivation tanks or cultivation excavation tanks that have been excavated in the field. It means the ground that can be made, and at least it has water permeability (thus, it does not adhere to the turf like clayey ground), and the turf root of the turf that has grown in this artificial ground enters, Next, when the sheet is peeled from the artificial ground, the turf does not break off from the turf, and the ground is not adhered to the turf removed from the artificial ground, or a ground material that is difficult to adhere is spread. It is a ground that can be done.

  In addition, it is desirable that the sheet for preventing soil erosion laid on this artificial ground and cultivating the lawn on the artificial ground should be lightweight, for example, non-woven fabric, plant material fiber net, etc. It is preferable to apply a sheet having excellent turf fixing properties and excellent water permeability.

  A sheet for preventing soil erosion is laid on the artificial ground, and a turf mat is stretched on the artificial ground, or a turf stem is sown, for example, covered with soil to grow the turf.

  After a predetermined period of time, the turf root penetrates from above the sheet and roots in the artificial ground, whereby a greening sheet in which the sheet and the turf are integrated is formed.

  Once the sheet and turf are integrated, a greening sheet can be obtained by peeling off the greening sheet from the artificial ground, etc., but also in this stripping, the artificial ground has good water permeability as described above, in other words, Because it is a non-clay-based ground material with adhesive strength, the turf can be peeled off from the artificial ground, and the ground material does not easily adhere to the turf. Therefore, the weight of the greening sheet after peeling off remains still light.

  The turf grows well on the surface, and almost all the turf roots extend from the back of the sheet without being cut off from the turf. A greening sheet is obtained that is excellent in both the ability to carry the gradient to the slope and the laying workability, and also has a good energizing performance on the slope.

  Here, the turf described above is preferably Japanese turf.

  Most of the turfgrass seeds contained in vegetation sheets applied to slope planting by applying the current geotextile construction method are grass species derived from alien species such as western turf. Since these alien species include plants designated as alien species requiring attention, it is not desirable to introduce a vegetation sheet containing western turf seeds from the viewpoint of biodiversity conservation.

  Therefore, in addition to the above effects, a greening slope with less environmental impact can be formed by producing the above greening sheet with Japanese turf on its surface and laying it on the slope. .

  That is, the present invention also includes a slope greening method in which the greening sheet produced by the above production method is laid on a slope that has been created. In addition to the newly constructed slopes in the new construction area, the restoration slopes newly created at the time of restoration of slope slopes such as landslide disasters are also included. And, especially in the latter aspect, the greening of the restoration slope in the shortest possible time is the most important issue, so abnormal weather and landslide disasters caused by this are increasing. In view of the above, the slope revegetation method of the present invention is suitable for these restoration works, and its application is expected to increase in the future.

  Examples of this slope greening method include a method of laying a greening sheet produced on the slope and placing the greening sheet on the back of a wall material made of a steel frame by the geotextile method described above. be able to. That is, by applying the greening sheet produced by the production method of the present invention to the conventional geotextile construction method, the problems described in the case of the conventional geotextile construction method, that is, the turfgrass mat is easily collapsed during construction, and the method While solving the problems such as taking a lot of time to fix the surface, frequent watering over the period until the turf takes root, and increasing the environmental impact load due to the introduction of foreign species, A green surface with turfgrass can be formed uniformly on the entire slope at an early stage.

  As can be understood from the above description, according to the method for producing a greening sheet of the present invention and the method for greening by applying the greening sheet produced by this method, the lawn grows well on the surface. Almost all turf roots of the turf extend from the back of the sheet without breaking off from the turf, and further, a greening sheet having a light weight as a whole can be obtained, so that a uniform slope can be obtained in the shortest possible period. Greening can be realized with excellent workability.

It is the schematic diagram explaining a part of manufacturing method of the greening sheet of this invention. FIG. 2 is a schematic diagram illustrating another part of the method for producing the greening sheet following FIG. 1. It is the longitudinal cross-sectional view which showed typically the greening slope formed by the slope greening method of this invention. (A) is the figure which shows the situation (comparative example) which stored black my earth in the cultivation tank as artificial ground in order from the left, and shows the situation (example) which accommodated volcanic gravel in the cultivation tank as artificial ground. It is a figure, (b) is a figure which shows the condition where the sheet | seat for soil erosion prevention was each laid on the artificial ground of a comparative example and an Example, (c) implemented lawn covering on the sheet | seat. (D) is a figure which shows the growth condition of the turf 40 days after lawn covering.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, although the manufacturing method of the greening sheet | seat shown in FIGS. 1 and 2 shows the method of manufacturing in the cultivation tank of desired shape and a dimension, for example, the shape and dimension desired for the ground in an agricultural field, for example An excavation tank for cultivation may be created, and a greening sheet may be produced here. In addition, although the plan view of FIG. 1 is omitted, the illustrated cultivation tank has an extremely wide area (when the greening sheet is formed, it is cut into a predetermined plane size and peeled off from the artificial ground), relatively The planar shape and size are arbitrary, such as a form in which a plurality of small planar dimensions are prepared.

  FIG. 1 and FIG. 2 are schematic views illustrating a method for producing a greening sheet of the present invention in order.

  First, the cultivation tank T surrounded by a frame having a height of about 10 cm is placed on the field ground G, and a root-proof sheet S is laid on the inside. Here, although the frame material forming the cultivation tank T is desirably wooden, at least, if it is of a material or structure that allows the excess water in the artificial ground to be drained to the outside appropriately from the end or bottom of the frame, metal Either a material or a resin (plastic) material may be used.

  Next, in the cultivation tank T covered with the root-proof sheet S, soil with good drainage properties such as gravel J is spread and leveled to form the artificial ground 1 for lawn cultivation. Here, the gravel J used for the artificial ground 1 is volcanic gravel, coarse sand, boulder gravel, crushed stones such as crusher run, etc., when a suitable gap is formed, that is, grass turf grows in this gap. When the turf is peeled off, the turf can be smoothly separated from the artificial ground through the gap, and the material is not limited to gravel as long as the material has good drainage.

  For example, a sheet 2 used for preventing soil erosion in civil engineering work is laid on the artificial ground 1, and a mat of turf G is spread on the sheet 2 or a turf stem is sown to cover the soil. The grass is cultivated on the artificial ground 1 through the sheet 2.

  Here, the sheet 2 is preferably made of a lightweight material, such as a nonwoven fabric or a fiber net of plant material, which has good entanglement with the turf, has excellent turf fixing properties, excellent water permeability, and the like.

  In addition, it is desirable to apply Japanese turf to turf from the viewpoint of biodiversity conservation.

  In the state of FIG. 1, for example, when cultivation and curing are performed for a period of about one month, the turf root N of the turf G penetrates the sheet 2 and extends into the artificial ground 1. Integrate via N.

  By cutting the sheet 2 from the artificial ground 1 with a predetermined plane dimension, the sheet 2 and the turf G are integrated with the grass root N penetrating from above the sheet 2, and a predetermined plane is obtained. A greening sheet 10 having a shape and planar dimensions is produced.

  Here, turf N is extended to a gap formed between gravel rich in drainage and adjacent gravel, and since it does not have adhesive strength like viscous soil, turf N is It is easily peeled off from the artificial ground 1 (therefore, the turf is not cut off from the turf), and the artificial ground is not attached to the surface in the peeled posture, and the total weight of the greening sheet is light. Become.

  By planting the greening sheet 10 produced by the production method shown in FIGS. 1 and 2 on the slope, the slope greening can be achieved. Here, with reference to FIG. 3 which shows a greening slope structure, the slope greening method is outlined.

  FIG. 3 shows a greening slope 100 configured by laying a greening sheet 10 manufactured by the method described in FIGS. 1 and 2 on a slope created by applying the geotextile method.

  First, in order to outline the method of slope preparation, a geotextile GT is laid on the ground, a sandbag (not shown) is set up, the embankment is sown and leveled, and the ground is compacted. Form. Here, as the geotextile GT, woven fabric (geo oven), non-woven fabric (geonon oven), knitted fabric (geo knit), geogrid, geonet, and the like can be applied.

  On the slope, the greening sheet 10 carried in the field was laid over a predetermined range, and a steel frame KW was attached to the front surface thereof, or the greening sheet 10 and the steel frame KW were assembled in advance. A greening slope 100 is constructed by laying things on the slope.

  The greening sheet 10 shown in the drawing is easy to manufacture, and the turf root extends from the back of the turf without breaking, the turf G is dense on the sheet 2, and is extremely lightweight. Thus, it is excellent in laying property (constructability) on the construction slope, and it is possible to form a uniform greening surface in a short period over the entire construction slope.

[Verification experiment and results on the greening sheet weight and its ability to be attached to the slope]
The present inventors prepared two cultivation tanks having a wooden frame of 10 cm in height and a plane area of about 20 m ² , and one of them was used in the cultivation tank by using black soil as artificial ground material. The other one was the one that was leveled (comparative example) and the other was the one that was leveled in the cultivation tank using gravel lava (gravel) as the artificial ground material (Example). And, on the artificial ground of each cultivation tank, a sheet for preventing soil erosion (Netron vegetation sheet 85 (manufactured by Nissin Sangyo Co., Ltd.)) was laid, and a 30 cm square noshiba mat was spread on the sheet, and fertilization and mesh sand were applied. Scattered. In addition, in FIG. 4, the manufacturing method of the actual greening sheet | seat in the said experiment is shown as a photograph figure. Here, FIG. 4a is a diagram showing a comparative example and an example in order from the left, and FIG. 4b is a diagram for laying a sheet for preventing soil erosion on the artificial ground of the comparative example and the example, respectively. FIG. 4c is a diagram illustrating a situation where turfing is performed on a sheet, and FIG. 4d is a diagram illustrating a turf growth situation 40 days after the turfing.

  Watering is carried out at a rate of about once a week for each cultivation tank of Examples and Comparative Examples, and after about two months, it is confirmed that turf has penetrated the sheet in any cultivation tank. did. At this stage, a cut was made in the lawn and the sheet with a size of 30 cm square, and the edge of the sheet was peeled off from the artificial ground or the like to obtain a greening sheet specific to each of the examples and comparative examples.

  In this stripping, in the cultivation tank of the comparative example laid with black soil, a sheet with soil of about 5 cm in thickness was cut out, but when the sheet was peeled off from the cultivation tank of the example laid with gravel lava The turf was removed smoothly from the inside of the lava, and the lava adhering to a part of the turf also dropped into the cultivation tank, and the turf penetrating the sheet was exposed.

  The results of measuring the weight of the cut greening sheet are shown in Table 1 below. In addition, the measurement result of the turf mat cut out from the lawn open space built in the field is shown as a reference example.

[Table 1]

  From Table 1, the sheet of the comparative example was about 13.0 kg per 30 cm square, whereas the greening sheet of the example was about 5.7 kg, which was about 40% of the weight of the comparative example. Moreover, the weight of the turf mat of the reference example was 7.1 kg.

  These two types of greening sheets and Japanese turf cut out from the park were fixed on a slope with an inclination angle of about 20 degrees with three skewers, and the root survival and greening degree after one month were measured. Table 2 shows the results of measuring the survival rates of the examples, comparative examples, and reference examples.

[Table 2]

  From Table 2, it is demonstrated that the greening sheet of the example has good rooting equivalent to the greening sheet of the comparative example.

  Further, from FIG. 4d, it can be confirmed that the example in which the artificial ground is applied has a good turf growth state as in the comparative example.

  In addition, considering the weight comparison of the greening sheet by the above verification experiment and the survival situation in the creation method, the greening sheet produced by the production method of the present invention is used to green the creation method surface. An excellent greening slope can be constructed in a short period of time with excellent workability, and has a markedly superior effect over conventional slope greening methods.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Artificial ground, 2 ... Sheet (sheet for prevention of ground erosion), 10 ... Greening sheet, 100 ... Greening slope, G ... Grass, N ... Shibane, J ... Gravel, S ... Root prevention sheet, T ... Planting Planting tank, G ... field ground, NM ... slope, GT ... geotextile, KW ... steel frame

Claims (4)

A sheet for preventing soil erosion is laid on a water-permeable artificial ground that does not adhere to the turf ,
Growing grass on the sheet, forming a greening sheet on the artificial ground through which the grass root penetrates from the sheet and integrating the sheet and the grass, and separating the greening sheet from the artificial ground How to make a sheet.   The manufacturing method of the greening sheet | seat of Claim 1 with which the said sheet | seat consists of a nonwoven fabric.   The method for producing a greening sheet according to claim 1, wherein the turf is Japanese turf.   The slope greening method which lays the greening sheet | seat manufactured by the manufacturing method in any one of Claims 1-3 on the created slope.

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