JPH0465170B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is based on sand or sandy soil, silt, clay soil, or organic soil, either alone or in a mixture, mixed with cement, organic fibers, etc. A slope for greening in which a sprayed material is made and the sprayed material is applied onto the slope in steps to create concavities and convexities that are connected in the substantially horizontal direction of the slope to form a construction base. Concerning improvements in construction methods.

[Prior art] Originally, slopes formed by civil engineering methods have soil conditions that are not suitable for plant growth, and even if plants were introduced and planted, it would take a long time for the plants to take hold on the surface of the ground or In many cases, the soil is destroyed due to weathering, runoff, sliding, etc. Slope stabilization methods conventionally used for such slopes include masonry construction, block construction, concrete slope construction, block construction, and concrete or mortar spraying. All of these basic construction methods create conditions that are difficult for the plants introduced for greening to grow.

The growth of green plants requires soil stability, light, temperature,
Ventilation, water retention, nutrients, etc. must be adequate.

In recent years, a technique has been known in which organic fibers such as sand and peat moss as a soil admixture are mixed into Hoatland cement to form fiber soil cement. By using such fiber soil cement, it is possible to simultaneously protect slopes and grow plants. Therefore, by using fiber soil cement, slopes can be suitably protected.

However, if fiber soil cement is simply sprayed onto the slope, the wind and rain will erode all surfaces substantially evenly, and the moisture evaporation due to solar heat will occur evenly on all sides, so the seeds will not be exposed to the wind and rain. The drawback was that plants that had sprouted after a long time could wither and die depending on the terrain or direction.

Therefore, when spraying fiber soil cement onto the slope, the applicant
In addition to simply spraying fiber soil cement uniformly onto a slope, the fiber soil cement sprayed material is made to have an uneven shape, and each of the concave and convex portions is formed into a step shape that extends approximately horizontally. We first proposed the greening method (Special Public Interest Publication in 1982)
-Refer to Publication No. 54214).

According to this construction method, the following excellent effects can be obtained.

() With regard to water, which is essential for plant growth, the greening base's expanded surface area and its concave and convex parts retain rainwater more easily than conventional smooth surfaces.
Solving the problem of rainwater retention on slopes.

() Growth of grass on slopes The steeper the slope, the weaker the root growth and the thinner the root layer. Easy to grow and flourish.

() Regarding the invasion of local plants, if there are concavities and convexities in the greening base, it will naturally be easier to retain incoming seeds, and the degree of establishment on the slope will be extremely high. This is also convenient for permanent greening through plant succession.

() This step-like design has a remarkable effect in preventing erosion caused by rainwater. That is, rain water that permeates the slope is guided to the convex portion by the concave portion, and the flow velocity of surface water is moderated by the concave portion and the convex portion, which is effective from the viewpoint of forest management.

() Fiber soil cement stabilizes the soil through its adhesion, and also controls light, temperature, ventilation, water retention,
Since the nutrients are appropriate, the growth of plants and the protection of the slope can be satisfied at the same time, and the protection of the slope can be suitably carried out from the standpoint of disaster prevention.

[Problems with the prior art] Although the known slope construction method for greening exhibits various excellent effects as mentioned above, it is not possible to properly deal with the wide variety of ground shapes. According to subsequent experimental results, the present inventors found that it was necessary to make further improvements in the structure of the convex portion of the step of the constructed base.

In other words, if the upward angle between the upper part of the step convex part of the constructed foundation and the horizontal level is too large, water will accumulate on the steps, making the constructed foundation easy to collapse, and also inhibiting the growth of plants. If the downward angle is too large, there is a risk that seeds will flow out, and plants will not grow upward. Also, if the apex angle of the step protrusion is too small, it will become too sharp and the step will become weak.
Moreover, there is no room for dividing the roots of plants and trees, and conversely, if it is too large, it will not function as a step spray. Furthermore, if the step interval is too large, especially if the slope is steep, the step interval will be longer than the height of the grass, and the entire slope will not be covered with grass, resulting in poor visibility.

[Problems to be Solved] Therefore, an object of the present invention is to provide a slope for greening that does not cause seeds to flow out, has good growth of plants, and can cover the entire slope with plants even on a steep slope. We provide construction methods.

[Means for solving the problem] According to the present invention, sand or sandy soil, silt,
A sprayed material is made by mixing clay soil or organic soil or a mixture thereof with cement, organic fibers, etc., and the sprayed material is placed on a slope with concave and convex portions extending approximately horizontally on the slope. In the slope construction method for greening, in which soil is sprayed in steps to form a built-up base, the convex parts formed on the built-up base are the distance between the vertices that protrude perpendicularly from the slope. is within 1 m, the maximum thickness of the protrusion from the slope is within 50 cm, and the angle at which the tangents of both bases of the protrusion intersect is between 45 degrees and 140 degrees,
A convex portion is formed within a triangle formed between both tangents and the base, and the angle between the tangent to the base located above the convex portion and the horizontal level is 0 to 30 degrees.

[Function] If the distance between the vertices of the convex parts is 1 m or more, it is inappropriate to cover the entire slope when the slope is steep because the height of the plants for normal slope vegetation cannot cover the entire slope. If the distance is within 1 m, flying seeds and fallen leaves will be retained at the convex part, and greening can be substantially achieved.

Furthermore, if the length of the apex of the convex portion (the length in the direction perpendicular to the slope) is 50 cm or more, it is uneconomical and does not have much meaning in terms of the growth of plants.

If the structure of the convex part is too protruding, that is, if the cross-sectional shape is triangular with a small acute angle, the apex will be destroyed by wind and rain. Therefore, the angle at which the tangent lines of the bases on both sides of the convex part intersect is between 45 degrees and 140 degrees.
It is formed within a degree triangle. If this angle is less than 45 degrees, the vicinity of the apex of the convex part tends to collapse, forming a weak convex part, and there is no part for the roots of plants to grow, which is inconvenient for growth. If this angle is more than 140 degrees, it will no longer function as a step.
Flying seeds and fallen leaves are no longer retained in the convex part.

Furthermore, if the angle between the tangent from the base located above the convex part and the horizontal level is less than 0 degrees, seeds will flow out due to rainwater or wind, and if it is more than 30 degrees, rainwater will accumulate in the concave part, which is inconvenient. .

As described above, according to the present invention, it is possible to obtain a greening method that is durable and suitable for the growth of plants and trees.

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

FIG. 1 shows a first embodiment of the present invention, and this embodiment is applicable when the inclination angle θ1 of the slope 1 with respect to the horizontal level L is relatively small. Suitable for construction to encourage the flight of plant seeds.

In FIG. 1, a slope 1 is a sloped surface of bedrock or earth and sand, and a base 3 is created by spraying a spray material 2 mixed at a mixing ratio described later, as an example, onto this slope 1. The spray material 2 is sprayed onto the slope 1 in a step-like manner so as to form concave portions 3a and convex portions 3b which face substantially horizontally on the slope 1.

Vertex 4c of these adjacent convex portions 3b, 3b
The length l between the vertices (vertices protruding in the right angle direction of the slope 1) is within 1 m, and the length h from the apex 4c to the slope 1 (the length of a line drawn in the right angle direction from the slope 1) ) is less than 50cm.

Then, when imaginary tangents a and b are drawn along the side surfaces of the convex portion from the bases 4a and 4b of the convex portion 3b, that is, the portion rising from the concave portion 3a, the intersection angle θ3 of the imaginary tangents a and b is 45 degrees to 140 degrees. within the range of degrees. Further, the angle θ2 formed by the virtual tangent a located above the convex portion 3b and the horizontal level L is from 0 degrees to 30 degrees.

Figure 2 shows steep slope 1 with a relatively large angle θ1.
This is the case when the test was carried out. In the illustrated example, the side surface 5 above the convex portion 3b is formed horizontally, so θ2 is 0 degrees and θ3 is 90 degrees.

Next, an example of the mixing ratio of the spray material 2 will be shown.

Sand or sandy soil, silt, clay soil, organic soil alone or in combination 500-2000Kg/m ^3Admixture 50-200Kg/m ^3Cement 10-200Kg/m ^3Organic fiber (peat moss, pulp lees, etc.)
~1500/ ^m3 Fertilizer (organic fertilizer, quick-release fertilizer, slow-release fertilizer) is the basic mixture of seeds, and depending on the site situation, weather conditions, and greening purpose, curing agent (coating chemical glue such as S-Fix, Lunazur, etc.) ) Additives (flocculants, hormones, surfactants, microorganisms) are added.

The following points were taken into consideration when formulating the proportions of this sprayed product: () The standard composition so far had sand or sandy soil as its main component, but by adding silt, clay soil, or organic soil to this, it was possible to It improves the physical properties of the base.

In other words, silt and viscosity bind and fill the particles and pores of the composition material, and also form a network structure through hydration reaction with cement, thereby improving physical properties. Furthermore, silt and viscosity retain fertilizer nutrients and act as a breeding ground for microorganisms, creating humus and silicate complexes, which play an extremely important role in improving soil fertilization and provide good physical properties for plant growth.

Silt, clay soil, and organic soil can be used alone or in combination, and the lower limit for the amount used is 500 kg/m ³ , which maintains the appropriate density of the plant growth base to be created, and most of the base is made of this. The upper limit shall be 2000Kg/ ^m3 .

() In the conventional standard mix, the amount of cement used was 10 to 25 kg/m ³ . This compounding amount is an appropriate amount for early greening, and is suitable for construction site conditions, such as sites where safety measures such as strong rockfall protection are first satisfied and then gradual greening is to be carried out, such as steep slopes and Cement has not been used in the past for sites where the foundation must be attached to the slope of an overhang, sites where heavy rain is expected immediately after foundation construction, sites where it rains continuously during the rainy season, etc. However, there were disadvantages such as insufficient adhesion of the base, collapse, and erosion.

Therefore, in order to improve this drawback, if the plant adheres well to the ground and the germination and growth of the plant is considered from a long-term perspective, 100 kg/kg, which is the limit of growth.
The upper limit is ^m3 .

() Up to now, the standard mix was to add cement to sand or sandy soil and add a maximum of 200 kg/m ³ as a mixed material (peat moss, etc.).
In sites that are poor for plant growth (mortar/concrete surfaces, completely soilless rock surfaces, etc.), it is necessary to satisfy the water retention, fertilizer retention, and ventilation necessary for plant growth with the constructed foundation alone. However, there was a drawback that the addition of a maximum of 200 kg/m ³ of the mixed material alone was slightly inferior. Therefore, as an improvement, organic fibers (peat moss, pulp lees, etc.) up to a maximum of 1500/m ³ are added as appropriate depending on the site conditions.

() The most desirable fertilizer for slope greening is one that lasts all year round and has a well-balanced composition in order to achieve the primary purpose of protecting slopes by promoting healthy growth in both summer and winter. be. Therefore, organic fertilizers that can supply trace nutrients, fast-acting fertilizers with strong soil adsorption ability,
By mixing and applying a strong slow-release fertilizer, the purpose of slope greening can be satisfied.

() In addition, chemical coating agents, flocculants, hormones, surfactants, microorganisms, etc. are added depending on site conditions, weather conditions, and various greening purposes.

[Effects of the Invention] As described above, the present invention provides the following excellent effects.

(1) Water will not accumulate near the base above the convex part of the step and the foundation will not collapse.

(2) Seeds do not flow out and plants grow upward.

(3) The convex part of the step is strong and will not collapse due to rain or wind.

(4) There is sufficient room for dividing the roots of plants and trees.

(5) Even if the slope is steeply sloped, plants can sufficiently cover the slope.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views of various types of slope protection works for greening constructed according to embodiments of the present invention. 1...Slope surface, 2...Spraying material, 3...Created base,
3a...Concave portion, 3b...Convex portion, 4a, 4b...Base, 4c...Vertex, 5...Side surface, a, b...Virtual tangent, L...Horizontal level.

Claims (1)

[Claims] 1. Make a sprayed product by mixing sand, sandy soil, silt, clay soil, organic soil, or a mixture of sand or sandy soil, silt, clay soil, or organic soil as the main component with cement, organic fiber, etc.
In the slope construction method for greening, in which the sprayed material is sprayed onto the slope in steps to form concave and convex portions that are continuous in the substantially horizontal direction of the slope to form a construction base, The convex parts formed on the base have an interval of 1 between the vertices that protrude perpendicularly from the slope.
m or less, and the maximum thickness of the protrusion from the slope is 50 cm.
and the angle at which the tangent lines of both bases of the convex part intersect is between 45 degrees and 140 degrees, and the convex part is formed within the triangle formed between both of the tangent lines and the base, and the convex part is A slope construction method for greening, characterized in that the angle between the tangent line of the base located above and the horizontal level is 0 degrees to 30 degrees.