JPH04203013A - Preventing work for run-off surface soil by rain water - Google Patents

Abstract

PURPOSE:To prevent the run-off of surface soil by rain water by a method in which a mixture of a soil hardener, soil, and water as matrix material is sprayed onto the surface of ground area to be treated to cover the surface of soil. CONSTITUTION:A reaction accelerator such as quick lime as a soil hardener solution, soil taken from the ground to be treated, and vegetable fibers cut to an adequate length are mixed together in a mixer to prepare a matrix slurry. The slurry is sent to the ground area to be treated by a pump and sprayed thinly to the surface of the ground by a spray gun set on the tip. In this case, the slurry being sprayed is mixed with a plant seed during mixing period and sprayed. Thereafter, the hydrating reaction of the matrix slurry exceeds with permeation of rain water, together with hardening of the soil and growth of plant concurrently.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a construction method for preventing topsoil from flowing out due to rainfall from bare land such as reclaimed land.

(Conventional technology) Recently, with the development of Corfu fields, housing development, road construction, land improvement, etc. in mountain forests and wilderness areas, topsoil is washed away from the bare land of these sites during heavy rains, causing rivers and oceans to flow. It has become a major social problem that pollutes and destroys the environment. In particular, in the Okinawan region, acidic topsoil called red soil is flowing into the sea in such large quantities that the coast is dyed bright red, causing the death of coral and seafood, and countermeasures have become an urgent issue. .

Conventionally, as a measure to prevent the pollution of seas and rivers by red soil, a red soil sedimentation pond (sand basin) was installed at the end of the river, and the red soil particles were allowed to settle, and then the supernatant liquid was allowed to overflow. Since most of the particles are fine particles, they take a long time to settle, and they do not arrive in time during heavy rains, so they end up being washed away and are not effective in preventing red soil from flowing out.

Therefore, there has recently been a call for the need to take measures to prevent red soil from flowing out when it rains by taking measures at its source, and the following methods have been adopted as countermeasures.

The most commonly known methods of preventing topsoil runoff at the source are spraying mortar on the surface to cover it, or covering the land surface with high molecular weight polymer, lime, or asphalt emulsion. . However, these construction methods cover the land surface in a state where water cannot penetrate, which impedes the growth of leather etc. and causes secondary pollution.

In particular, petroleum polymers do not corrode semi-permanently,
There are many problems with recovery. Moreover, these conventional construction methods not only impair the aesthetic appearance after construction, but also have the problem of high construction costs and high economic burden.

As mentioned above, various construction methods have been proposed as measures to prevent topsoil runoff, but no effective method has yet been established.

(Problems to be solved by the invention) The present invention was devised in view of the above-mentioned circumstances, and eliminates the drawbacks of conventional topsoil runoff prevention measures, and can effectively prevent topsoil runoff. The purpose of this invention is to provide a new topsoil runoff prevention method that promotes plant growth, can be easily constructed at low cost, and can be effectively applied to farmland and slopes.

(Means for Solving the Problems) As a result of various studies in order to solve the above problems, the inventor of the present invention has determined that an inorganic soil hardening agent and soil are mixed with water to form a slurry and that The present invention was developed based on the foresight that by spraying the surface with water, the surface would easily condense and harden, thereby preventing surface soil from being washed away by heavy rain.

That is, the method for preventing topsoil runoff caused by rainfall according to the present invention is characterized in that a soil hardening agent and soil are mixed with water to obtain a matrix, and the matrix is sprayed onto the soil surface of the area to be treated to cover the topsoil.

Depending on whether an inorganic silica compound is used as the soil hardening agent, it also serves as a soil conditioner and promotes plant growth. In addition, by using soil collected from the area to be treated as the above-mentioned material that makes up the matrix, it is inexpensive, blends well with the soil at the site, and does not change the properties of the soil. ,
Can be constructed effectively.

Furthermore, by stirring and mixing plant fibers cut into a certain length into the matrix, the curing speed and coating strength can be increased and the coating effect can be promoted.

As the plant fiber, suitable materials such as plant fibers such as thatch and straw, or sawdust can be used. By stirring and mixing plant seeds into the matrix, planting can be done at the same time.

(Function) The matrix that is thinly sprayed on the ground surface of the area to be treated begins to harden immediately after construction, and the infiltration of water from rainfall increases the hydration reaction of the matrix and promotes soil hardening. Therefore, construction can be carried out regardless of construction conditions, even during the rainy season. and,
Since the main component of the matrix is soil, just like at the construction site, it remains unnoticeable even after construction and does not impair the beauty of the surrounding area.

By mixing organic fibers, the organic fibers can strengthen and harden the soil paste that is thinly sprayed on the ground surface, prevent the occurrence of cracks after the paste dries and hardens, and increase the self-shape retention during concentrated rainfall. . Furthermore, after treatment, the soil mixed with organic fibers becomes aggregated when cultivated, and becomes a soil conditioner suitable for planting. Therefore, the method of preventing topsoil runoff due to rainfall according to the present invention can effectively prevent the topsoil such as red soil from running away immediately after construction, and the hardened topsoil has excellent air permeability, and the organic fibers mixed in do not change over time. It also has the effect of promoting decomposition and promoting plant growth.

(Example) Hereinafter, an example of the method for preventing topsoil runoff due to rainfall according to the present invention will be described in detail.

The soil hardening agent employed in the present invention contains silicon dioxide with a content of 30 to 50%
%, calcium chloride 30-45%, magnesium oxide 8
-16%, ferric chloride 3-8% as the main component, which neutralizes the matrix to form a water-density compound, forming a material that is water resistant and resistant to physical changes. Excellent.

In this example, the component ratios are 38% silicon dioxide, 38% calcium chloride, 12% magnesium oxide, 6% ferric chloride, and 6% others, and the soil hardening agent is diluted with water to It was used as a 30% solution.

The soil hardening agent solution, an appropriate reaction accelerator such as quicklime, soil collected from the area to be treated, and vegetable fibers cut into appropriate lengths are mixed with water in a mixer to form a slurry matrix. make.

The matrix thus created is pumped to the area to be treated using a pressure pump, and a spray gun at the tip of the matrix is used to spray a thin layer onto the ground surface to be treated.

In addition, when mixing with a mixer, the grass seeds are also mixed at the same time, and spraying the seeds on the ground surface in the spray state of the matrix thriller is suitable for making them take root.

Experimental Example The following experiment was conducted to confirm the effects of this example.

Length x width x height = i20mm x 200m +++ x 50mm
Build a basin and provide a single outlet for the water at the bottom.
An experimental device was prepared by filling the basin with 1.2 m'' of soil. Also, a matrix was prepared under the following conditions (each ratio is relative to 100% soil).

Soil hardening agent 20% diluted liquid 20% quicklime
10% water
30% the same type of soil as the soil filled in the box ± 100% 5~5O1TI
A matrix made by stirring and mixing 15% of the above ingredients with a thickness of 51TIITl.
When sprayed on the surface of the soil in the box, it hardened after about 4 hours.

After that, a large amount of water was showered like a torrential rain on the surface of the soil covered with the hardened matrix, and when the water flowing outward from the surface was observed to observe its turbidity, it was found that most of the turbidity was due to soil runoff. Not observed. In addition, water was observed to flow out from the water outlet, and it was confirmed that water permeated into the soil through the covering layer.

The soil was left in the open for one month, and during that time there were three heavy rains, but the surface of the soil remained largely unchanged except for a few cracks, and no runoff of the topsoil was observed.

After that, when the soil was tilled, it was extremely easy to till, and the tilled topsoil had a granular shape, and the soil was extremely permeable and suitable for planting.

As described above, the construction method of the present invention is extremely effective in preventing topsoil runoff, and can be applied to all bare land sites such as slopes, slopes, and farmland.

Next, an example of applying this construction method to sloping farmland will be shown.

When applied to farmland on a slope, planting ridges are formed along the contour lines of the slope, and the matrix is sprinkled on one side of the ridge facing the sea. In that case, if the matrix is not large enough to be sprayed with a pressure pump,
A slurry-like matrix can be easily obtained by simply bringing only the soil hardening agent and reaction accelerator to the site, and mixing the soil at the site and the appropriate plant fibers found at the site with water in an appropriate container at the site. . Then, by appropriately spreading the slurry on one side of the sea side of the ridge,
It can be done easily and cheaply.

After harvesting, the covered 7 Trix becomes a soil conditioner by plowing along with the ridges, bringing multiple effects to the farmland. In this way, by repeating the above-mentioned construction every time the harvest is completed, it is possible to prevent topsoil from flowing out from the sloped field.

(Effects) The method for preventing earth and sand runoff caused by rainfall according to the present invention has the above-mentioned configuration, and has the following special effects.

Hardening progresses immediately after construction, and the infiltration of water from rainfall increases the hydration reaction of the matrix and promotes soil hardening.It can be constructed even during the rainy season depending on the construction conditions, and hardens the topsoil to ensure runoff during heavy rains. It can be prevented. Since the matrix that covers the surface of the area to be treated is mainly soil, it blends in with the surrounding environment without attracting attention.
It does not spoil the beauty.

Furthermore, since the soil hardening agent is an inorganic silica compound, there is no risk of secondary pollution, and on the contrary, it is effective as a soil conditioner.

The main component constituting the matrix is soil, and since it is possible to use soil collected from the area to be treated, it is inexpensive, has a good quality < 11 + 1 of the soil at the site, and improves the properties of the soil. It can be constructed effectively without any changes.

Furthermore, by stirring and mixing plant fibers cut into appropriate lengths into the matrix, the curing speed and self-shaping ability are increased, promoting the covering effect during torrential rains, and preventing the plant fibers from corroding in the future. , promotes soil agglomeration and has an effective effect on planting.

By stirring and mixing plant seeds into the matrix, planting can be done at the same time.

Claims (1)

[Claims] 1) Topsoil runoff due to rainfall characterized by mixing a soil hardening agent and soil with water to obtain a slurry-like matrix, and spraying the matrix onto the soil surface of a treatment area to cover the topsoil. Prevention method. 2) The method for preventing surface soil runoff due to rainfall according to claim 1, wherein the soil hardening agent is an inorganic silica compound. 3) The method for preventing surface soil runoff due to rainfall according to claim 1 or 2, wherein the soil constituting the matrix is soil collected from the area to be treated. 4) The method for preventing topsoil runoff caused by rainfall according to claim 1, 2 or 2, wherein vegetable fibers are stirred and mixed in the matrix. 5) The method for preventing surface soil runoff due to rainfall according to claim 1, 2, 3 or 4, wherein plant seeds are stirred and mixed in the matrix.