JP2020165269A - Slope protection layer, and slope protection method - Google Patents

Abstract

To provide a slope protection layer for protecting a slope that can use waste shells to realize resource saving and cost reduction, and a slope protection method.SOLUTION: Disclosed a slope protection layer is formed by supplying unbaked crushed shells and microorganisms to a slope 2. A method of slope protection comprises supplying unbaked crushed shells and microorganisms to a slope 2. Scallop shells are crushed and used as the crushed shells.SELECTED DRAWING: Figure 1

Description

The present invention relates to a slope protection layer formed by utilizing a shell and a microbial metabolism (microbial reaction), and a slope protection method.

Conventionally, as a slope protection method, a slope protection mat is fixed to a slope (see Patent Document 1), stone baskets are piled up as a slope protection (see Patent Document 2), and a wall material is used as a slope protection. It is known to be fixed (see Patent Document 3).

Japanese Unexamined Patent Publication No. 2008-208604 JP-A-2015-45133 Japanese Unexamined Patent Publication No. 2012-184605

In the conventional slope protection and slope protection methods described above, the material cost and the construction cost are high, and there is a problem that resource saving and cost reduction cannot be achieved.
An object of the present invention is to provide a slope protection layer and a slope protection method for providing slope protection capable of realizing resource saving and cost reduction by utilizing shells as waste.

According to the slope protection layer according to the present invention, since it is characterized in that it is formed by supplying crushed shells obtained by crushing unbaked shells and microorganisms onto the slope, shells that are wastes are used. It is possible to realize resource saving and cost reduction.
Further, according to the slope protection method according to the present invention, since the crushed shells obtained by crushing unburned shells and microorganisms are supplied to the slope, the shells as waste can be used. It is possible to realize resource saving and cost reduction.
Further, since the crushed scallop shell is used as the crushed shell, the scallop shell as a waste can be used, and resource saving and cost reduction can be realized.
Further, the slope is a slope formed by embankment, and the embankment is constructed by alternately laminating crushed shells solidified layers formed by supplying crushed shells and microorganisms and earth and sand layers. Because it is characterized by the fact that the slope protection layer formed on the slope and a plurality of crushed shell solidified layers are connected, the embankment has excellent water permeability and water resistance and is well drained. It will be possible to construct an embankment site with excellent collapse prevention effect.

FIG. 6 is a cross-sectional view showing the procedure of the slope protection method (Embodiment 1). FIG. 3 is a cross-sectional view showing an embankment site (Embodiment 3). The figure which shows the component ratio of each test piece used in Experiment 1. Numerical table showing the experimental results of Experiment 1. The graph which shows the experimental result of Experiment 1. The figure which shows the component ratio of each test piece used in Experiment 2. The graph which shows the experimental result of Experiment 2. Numerical table and graph showing the experimental results of Experiment 2.

Embodiment 1
As shown in FIG. 1, the slope protection layer 1 according to the first embodiment is formed by supplying a crushed shell product obtained by crushing an unfired shell and a microorganism to the slope 2.
Further, in the slope protection method according to the first embodiment for forming the slope protection layer 1, the slope protection layer 1 is provided by supplying crushed shells obtained by crushing unfired shells and microorganisms to the slope 2. I tried to form it.

The slope means an artificial slope formed by cutting or embankment, or a natural slope.
In addition, crushed shells are fragments formed by crushing (splitting) shells to almost the same size, coarse particles formed by crushing shells into coarse particles with a large particle size, and crushing shells into powder. Refers to the powder and the like formed in the above.

The unbaked shell is an inorganic-organic complex composed of about 95% by mass of an inorganic component and about 5% by mass of an organic component. The inorganic component is calcium carbonate, and the organic component is composed of a protein called conchiolin and chitin. Will be done.
The structure of the unfired shell is such that an organic sheet exists as a binder between the plate-shaped calcium carbonate layers, and the calcium carbonate layer and the organic sheet are bonded to each other.

Therefore, by supplying the unburned crushed shells and microorganisms to the slope soil, carbon dioxide (carbon dioxide ions) generated by the metabolic action of the microorganisms and calcium carbonate in the unburned crushed shells other than Calcium carbonate is deposited between the particles of the crushed shell by the mineralization reaction that reacts with calcium ions, the bond between the particles of the crushed shell (calcium carbonate layer) becomes stronger, and the crushed shells are bonded to each other. It is considered that a solidified layer of crushed shells is formed.
Furthermore, carbon dioxide produced by the metabolic action of microorganisms reacts with calcium ions present in the soil or supplied to the soil (mineralization reaction), and carbonates precipitated between soil particles. It is thought that the soil will solidify.
That is, when unburned crushed shells and microorganisms are supplied to the soil, the slope protection layer 1 having a high slope collapse prevention effect is formed by the synergistic effect of the solidification of the crushed shells and the solidification of the soil. it is conceivable that.

Specifically, the slope protection layer 1 may be formed through the steps shown in FIGS. 1 (a) and 1 (b).
(1) Mixing material leveling step As shown in FIG. 1A, a mixed material 3 prepared by mixing an unfired scallop shell crushed product and a yeast solution is spread on a slope 2.
The mixed material 3 may be produced by mixing a scallop shell crushed product and a yeast solution at a plant, a site, or the like.
Further, the yeast solution may be prepared, for example, by dissolving yeast (microorganism) and glucose (nutrient source metabolized by the microorganism) in pure water.
Further, as can be seen from the experimental results described later, the scallop shell crushed product is a scallop shell crushed product having a size corresponding to the size of the soil particles of the slope soil, preferably the soil particles of the slope soil. It is preferable to use a crushed scallop shell having a size equal to or less than the particle size.
Specifically, it is preferable to supply the soil with scallop shell crushed material having a size equal to or smaller than the particle size of the soil particles of the soil on the slope and microorganisms.
For example, when the slope soil is clay soil such as red soil, it is preferable to supply powdered scallop shell crushed products and microorganisms to the clay soil.
(2) Rolling Step As shown in FIG. 1 (b), the slope protection layer 1 is formed by rolling the mixed material 3 spread on the slope 2 with a rolling machine (not shown).
Therefore, the slope protection layer 1 having a high slope collapse prevention effect is formed by the synergistic effect of the solidification of the scallop shell crushed material and the solidification of the soil on the slope 2.

Since the slope protection layer 1 formed according to the first embodiment is formed by using scallop shells which are wastes, resource saving and cost reduction can be realized. That is, it is economical because unfired scallop shells, which have been waste, can be recycled. Moreover, since it is used as it is unfired, there is no cost related to firing, cleaning, etc., which is economical.

As can be seen from the experimental results described later, the slope protection layer 1 formed in the first embodiment is a support in which scallop shell crushed products are bonded and solidified, and are more firmly bonded to the soil on the slope 2. It becomes a scallop shell crushed solidified layer with high strength, and also has a high supporting strength of the soil on the slope 2, so that it becomes a slope protection layer 1 having a high effect of preventing slope collapse.
Further, the solidified layer of scallop shell crushed material forming the slope protection layer 1 is a porous body having many gaps between the scallop shell crushed materials, and has excellent water permeability and water resistance. It becomes a slope protection layer 1 having a high collapse prevention effect.

According to the slope protection method according to the first embodiment, the scallop shell crushed material is bonded to each other and solidified, and the scallop shell crushed material solidified layer having a high supporting strength is more firmly bonded to the soil on the slope 2. At the same time, the supporting strength of the soil on the slope 2 is also increased, so that the slope protective layer 1 having a high effect of preventing slope collapse can be formed.

Embodiment 2
In the first embodiment, the mixing material 3 prepared by mixing the scallop shell crushed product and the yeast liquid was spread on the slope 2, but the scallop shell crushed product, the yeast liquid and the earth and sand were mixed. The prepared mixed material may be spread evenly on the slope 2.
As the earth and sand, for example, mountain sand, red earth, or the like used in the experiment described later may be used.

According to the second embodiment, by mixing the earth and sand, as can be seen from the experimental results described later, there is a solidified layer of the scallop shell crushed material having a high supporting strength in which the scallop shell crushed material and the earth and sand are more firmly bonded. As a result, the slope protection layer 1 has excellent water permeability and water resistance and is highly effective in preventing slope collapse.

Embodiment 3
As shown in FIG. 2, when the slope 2 is a slope 2 formed by the embankment 10, the crushed shell solidified layer formed by supplying the crushed scallop shell and microorganisms to the embankment 10. 4. Alternatively, the crushed scallop solidified layer 4 formed by supplying the crushed scallop shell, the microorganism and the earth and sand, and the earth and sand layer 5 may be alternately laminated and constructed.
Then, the slope protection layer 1 described in the first embodiment or the second embodiment is formed on the slope 2 of the embankment 10 constructed in this way.
According to the method according to the third embodiment, since the embankment 10 was constructed by alternately laminating the crushed shell solidification layer 4 and the earth and sand layer 5, the slope formed on the slope 2 of the embankment 10 was formed. Since the protective layer 1 and the plurality of crushed shell solidified layers 4, 4 ... Of the embankment 10 are connected to each other, the embankment 10 has excellent water permeability and water resistance and good drainage, and the embankment has an excellent collapse prevention effect. You can build an embankment.

Although yeast has been exemplified as a microorganism, other microorganisms may be used.
Moreover, although glucose was exemplified as a nutrient source metabolized by microorganisms, other nutrient sources may be used.

Further, as long as the scallop shell crushed product contains water, it is not necessary to supply water.
Further, when the soil on the slope 2 contains water, nutrients and the like, only unbaked scallop shell crushed products and microorganisms may be supplied to the soil.

Further, as described above, it is preferable to supply the slope 2 with an unbaked scallop shell crushed product, a microorganism, and a nutrient source such as glucose metabolized by the microorganism, but the nutrient source is not always supplied. It doesn't matter. For example, it may be sufficient to simply supply the cultured and activated microorganisms and the unbaked crushed shells.

Further, it is preferable to supply calcium nitrate containing calcium ions, calcium chloride, or the like to the slope 2 because the mineralization reaction is promoted.

Further, if a pH adjuster is supplied to the slope 2, a mineralization reaction in which carbonate ions and calcium ions generated by a microbial reaction react with each other can be promoted, and a preferable soil improvement effect can be obtained.
That is, it is said that the pH environment of the soil for promoting the mineralization reaction in which carbonate ions and calcium ions generated by the microbial reaction react with each other is preferably pH 8 to 9, and the above-mentioned mineral or caucal Alternatively, by maintaining the pH environment of the soil at pH 8 to 9 by using a mixed fertilizer in which minekal and caucal are mixed, the mineralization reaction can be promoted and a preferable soil improvement effect can be obtained.

Further, in the above, an example in which a scallop shell crushed product is used as the uncooked shell crushed product has been shown. You may use it.

In the present invention, "supplying crushed unbaked shells and microorganisms to the slope" means supplying a mixture of crushed shells and microorganisms to the slope 2. Alternatively, it refers to supplying the soil with crushed shells and microorganisms separately.
Further, "supply" means supplying crushed shells and microorganisms to the surface of slope 2, supplying them into the soil of slope 2, or mixing them in the soil of slope 2. Say.

Experiment 1
An experiment was conducted to confirm the difference in the supporting strength of the solidified shell crushed material formed by the difference in the size of the crushed shell material.
As the crushed shell, an unfired crushed scallop (scallop) shell was used.

As shown in FIG. 3, the following test specimens were used.
-The test body 1 was a test body in which 8 g of calcium nitrate + 150 ml of yeast solution was supplied to 350 g of crushed scallop shells having coarse particles. 350 g of the coarse-grained scallop crushed product is 80 to 90% of the scallop shell crushed product having a particle size of 10 mm to 2 mm + 10 to 20% of the scallop shell crushed product having a particle size of 0.85 mm to 0.1 mm. As the crushed scallop shell, the trade name "scallop chip" and the product of Aomori Eco Cycle Industry Cooperative Company were used.
-The test body 2 was a test body in which 8 g of calcium nitrate + 150 ml of yeast solution was supplied to 350 g of crushed scallop shells having medium particles. 350 g of the medium-particle crushed scallop shell is 55 to 60% of the crushed scallop shell having a particle size of 2 mm to 0.85 mm + 40 to 45% of the crushed scallop shell having a particle size of 0.85 mm to 0.005 mm. As the crushed scallop shells of the medium particles, the trade name "Scallops and Genki" and the product of Aomori Eco Cycle Industry Cooperative Company were used.
-The test body 3 was a test body in which 8 g of calcium nitrate + 150 ml of yeast solution was supplied to 400 g of powdered scallop shell crushed product. The powdered scallop crushed product (400 g) is 100% scallop shell crushed product having a particle size of 0.106 mm to 0.005 mm. Made by Eco Cycle Industry Cooperative Company.
The yeast solution 150 ml was prepared by dissolving 8 g of yeast and 8 g of glucose in pure water.
Further, each of the test bodies 1, 2 and 3 was prepared by spreading scallop shell crushed material on the bottom of a predetermined container to a depth of 20 mm and then pouring 150 ml of yeast solution.
Then, each test body 1, 2, 3 is left in a room temperature environment (temperature 30 ° C., humidity 60%) for several days, and every day, the support strength of each test body 1, 2, 3 is increased. The situation was measured.
The support strength was measured by a Yamanaka hardness tester.

-Experimental results As can be seen from Fig. 4; Fig. 5, each of the test bodies 1, 2 and 3 was solidified, and in particular, the test body 2 in which the yeast was supplied to the medium-sized scallop shell crushed product was supported after 3 days. A solidified shell crushed product having a strength of 117.1 N / mm ² and a high supporting strength could be obtained.

From the experiment, it can be proved that the crushed scallop shell can be solidified by supplying 150 ml of the yeast solution prepared by dissolving 8 g of yeast and 8 g of glucose in pure water to the crushed scallop shell. It was.

As in the experiment, the reason why the crushed scallop shells could be solidified was firstly that they were produced by the metabolic action of the microorganisms by supplying the crushed shells of unbaked shells with microorganisms. Calcium carbonate is precipitated between the particles of the crushed shell by the mineralization reaction in which the carbon dioxide (carbonate ion) reacts with calcium ions other than calcium carbonate in the crushed shell, and the particles of the crushed shell It is considered that the bond between (calcium carbonate layers) became stronger, and the crushed shells were bonded to each other to form a solidified crushed shell.
Second, in the experiment, the crushed shells of unbaked shells were supplied with microorganisms and calcium nitrate, so that calcium ions in the calcium nitrate and carbon dioxide produced by the metabolic action of the microorganisms were supplied. By promoting the mineralization reaction that reacts with and depositing calcium carbonate between the particles of the crushed shell, the bond between the particles of the crushed shell (calcium carbonate layer) becomes stronger, and the crushed shells become stronger. It is considered that a solidified body of crushed shell was formed by combining and solidifying.

In particular, like Test Body 2, the scallop crushed product has medium particles (for example, the scallop shell crushed product having a particle size of 2 mm to 0.85 mm is 55 to 60% + the scallop shell crushed product having a particle size of 0.85 mm to 0.005 mm). When it is 40 to 45%), the gaps between the medium particles of the scallop shell crushed product become dense, the bond between the calcium carbonate layers becomes stronger, and a solidified body of the scallop shell crushed product having high supporting strength is formed. Conceivable.
Further, like the test body 1, the scallop crushed product has coarse particles (for example, scallop shell crushed product having a particle size of 10 mm to 2 mm 80 to 90% + scallop shell crushed product having a particle size of 0.85 mm to 0.1 mm 10 to 20). %), It is considered that the gap between the coarse particles of the scallop crushed scallop was large, so that the bond between the calcium carbonate layers was weakened and the supporting strength of the formed scallop crushed solidified body was not increased.
Further, when the scallop shell crushed product is powder particles (for example, the scallop shell crushed product having a particle size of 0.106 mm to 0.005 mm is 100%) as in the test body 3, the scallop shell crushed product itself is powdery particles. It is probable that the supporting strength of the formed crushed shell material did not increase because the supporting strength of the scallop was weak.

Experiment 2
An experiment was conducted to confirm the difference in soil improvement effect based on the difference in soil and the difference in the size of crushed shells to be supplied.

As shown in FIG. 6, the following test specimens were used.
1. 1. The test piece name "Yamasago" was a test piece obtained by supplying 8 g of calcium nitrate + 150 ml of yeast solution + a pH adjuster (0.5 g of Keikal + 19.5 g of Minekal) to 400 g of mountain sand.
2. The test piece name "red clay" was a test piece obtained by supplying 350 g of red clay with 8 g of calcium nitrate + 150 ml of yeast solution + pH adjuster (0.5 g of caical + 12.0 g of minecal).

3. 3. The test piece name "Yamasago + Hochu" was a test piece in which 400 g of mountain sand was supplied with 40 g of crushed medium-grain scallop shells + 8 g of calcium nitrate + 150 ml of yeast solution + pH adjuster (0.5 g of Keikal + 19.5 g of Minekal). ..
4. The test piece name "mountain sand + sail powder" was a test body in which powdered scallop shell crushed product 40 g + calcium nitrate 8 g + yeast solution 150 ml + pH adjuster (Keikaru 0.5 g + Minekal 1.5 g) was supplied to 400 g of mountain sand. ..
5. The test piece name "mountain sand + sail rough" supplied 380 g of mountain sand with 80 g of crushed scallop shells in the form of coarse grains (fragment) + 8 g of calcium nitrate + 150 ml of yeast solution + pH adjuster (0.5 g of Keikal + 5.5 g of Minekal). It was used as a test body.

6. The test piece name "red clay + sail powder" was prepared by supplying 200 g of red clay with 100 g of powdered scallop shell crushed product + 8 g of calcium nitrate + 150 ml of yeast solution + pH adjuster (0.5 g of caical + 12.0 g of minecal).
7. The test piece name "red clay + sailing" was a test piece in which 200 g of red clay was supplied with 100 g of crushed medium-grain scallop shells + 8 g of calcium nitrate + 150 ml of yeast solution + pH adjuster (0.5 g of caical + 12.0 g of minecal).
8. The test piece name "red clay + sail rough" is a test body in which coarse grain (fragment) scallop shell crushed product 100 g + calcium nitrate 8 g + yeast solution 150 ml + pH adjuster (Keikaru 0.5 g + Minekal 12.0 g) is supplied to 200 g of red clay. And said.

The mountain sand had a particle size of about 5 mm to 0.125 mm, and the trade name "mountain sand", manufactured by Nakajima Gravel, was used.
The red soil (clay soil) had a particle size of about 0.074 mm to 0.005 mm, and was used under the trade name "Yamasago" and manufactured by Nakajima Gravel.
As the crushed scallop shell, a crushed scallop shell obtained by crushing an unbaked scallop shell was used.
The medium-grain crushed scallop shells are 55-60% crushed scallops with a particle size of 2 mm to 0.85 mm + 40-45% crushed scallop shells with a particle size of 0.85 mm to 0.005 mm. The name "Scallops are fine", made by Aomori Eco Cycle Industry Cooperative Company.
The powdered scallop crushed product was 100% scallop shell crushed product having a particle size of 0.106 mm to 0.005 mm, and the trade name "scallop marker", manufactured by Aomori Eco Cycle Industry Cooperative Company was used.
The coarse-grained (fragment-like) scallop crushed product is 80 to 90% of the scallop shell crushed product having a particle size of 10 mm to 2 mm + 10 to 20% of the scallop shell crushed product having a particle size of 0.85 mm to 0.1 mm. , The product name "scallop chip", made by Aomori Eco Cycle Industry Cooperative Company was used.
As the above-mentioned Minekal, which is a converter lime fertilizer as a pH adjuster, the trade name "Kumiai Minekal", manufactured by Sangyo Shinko Co., Ltd. was used.
The above-mentioned silicic acid fertilizer as a pH adjuster used the trade name "Kumiai Silicic" and manufactured by Murakashi Lime Industry Co., Ltd.
Further, 150 ml of yeast solution was prepared by dissolving 8 g of yeast and 8 g of glucose in pure water.
A test piece using mountain sand is prepared by spreading mountain sand or mountain sand and crushed scallop shells on the bottom of a predetermined container to a depth of 40 mm, and then pouring 150 ml of yeast solution. did.
A test piece using red clay (clay) is prepared by spreading red clay or red clay and crushed scallop shells on the bottom of a predetermined container to a depth of 10 mm, and then pouring 150 ml of yeast solution. did.
Then, each test piece was left in a room temperature environment (temperature 30 ° C., humidity 60%) for 7 days, and the supporting strength of each test piece was measured every day.
The support strength was measured by a Yamanaka hardness tester.

-Experimental results Fig. 7 shows the results of changes in the supporting strength of the test specimens that did not supply the crushed shells, that is, the specimen names "mountain sand" and "red clay" in Fig. 6 over time. Shown.
As can be seen from the graph shown in FIG. 7, sufficient support strength was not obtained with the test specimens "mountain sand" and "red soil", which were only supplied with yeast solution without supplying crushed shells, and were expected. No soil improvement effect was obtained.

Specimen "mountain sand + sail (medium)", test body "mountain sand + sail (powder)", test body "mountain sand + sail (rough)" in which crushed shells of different sizes were supplied to mountain sand. , And the test body "red soil + sail (powder)", the test body "red soil + sail (medium)", and the test body "red soil + sail (rough)", in which crushed shells of different sizes were supplied to the red soil. Figures 8 (a) show the numerical values showing the results of the transition of the support strength obtained with time, and FIGS. 8 (b) and 8 (c) show the graphs showing the results of the transition of the support strength.

As can be seen from FIGS. 8 (a) and 8 (b), the test body "mountain sand + sail (middle)", the test body "mountain sand + sail (powder)", and the test body "mountain sand + sail (rough)" On the 5th day, an excellent soil improvement effect was obtained in which the supporting strength reached 117.1 N / mm ² .

Further, as can be seen from FIGS. 8 (a) and 8 (c), the test body "red soil + sail (powder)" is remarkably excellent in that the supporting strength reaches 480.6 N / mm ² on the third day. It was found that the soil improvement effect was obtained.

The first reason why the above-mentioned soil improvement effect was obtained is that carbon dioxide (calcium ion) produced by the metabolic action of microorganisms by supplying unburned crushed shells and microorganisms to the soil. Calcium carbonate is precipitated between the particles of the crushed shell by the mineralization reaction that reacts with calcium ions other than calcium carbonate in the crushed shell, and the bonds between the particles of the crushed shell (calcium carbonate layers) are formed. It is considered that the crushed shells became stronger and the crushed shells were bonded to each other to form a solidified crushed shell.
Secondly, in the experiment, since calcium nitrate was supplied, the mineralization reaction in which calcium ions in calcium nitrate react with carbon dioxide produced by the metabolic action of microorganisms was promoted, and calcium carbonate was promoted between the particles of the crushed shell. It is presumed that the precipitation of calcium nitrate strengthened the bonds between the particles of the crushed shells, and the crushed shells were bonded to each other to form a solidified crushed shell.
Thirdly, carbon dioxide produced by the metabolic action of microorganisms reacts with calcium ions existing in the soil or calcium ions in calcium nitrate supplied to the soil (mineralization reaction) to produce soil particles. It is considered that the soil was solidified by the carbonates precipitated between them.
That is, when unburned crushed shells and microorganisms are supplied to the soil, it is considered that the soil improvement effect is improved by the synergistic effect of the solidification of the crushed shells and the solidification of the soil.

Further, the mountain sand has a particle size of 5 mm to 0.125 mm, whereas the powdered scallop shell crushed product has a particle size of 0.106 mm to 0.005 mm, and the medium grain scallop shell crushed product has a particle size. The crushed scallop shells having a size of 2 mm to 0.005 mm and coarse grains (fragments) have a particle size of 10 mm to 0.1 mm.
That is, in the experiment, since the scallop shell crushed product having a particle size smaller than that of the mountain sand is supplied, the scallop shell crushed product enters between the mountain sand particles, and the bond between the mountain sand particles becomes stronger. It is presumed that the soil became stronger and had a high supporting strength.

The red clay has a particle size of 0.074 mm to 0.005 mm, whereas the powdered scallop shell crushed product has a particle size of 0.106 mm to 0.005 mm, and the medium grain scallop shell crushed product has a grain size. The crushed scallop shells having a diameter of 2 mm to 0.005 mm and coarse grains (fragments) have a particle size of 10 mm to 0.1 mm.

That is, the test body "red clay + sail (powder)" has a size corresponding to the particle size of the soil particles of red clay and the particle size of the powder particles of the powdered scallop shell crushed product. In other words, since the particle size of the soil particles of red soil and the particle size of the powder particles of the powdered scallop shell crushed product are almost the same (high), the fine spacing between the particles can be equalized. It is considered that the carbonates formed by the mineralization reaction were precipitated and hardened at the minute intervals between the equalized particles, so that the entire red soil was solidified as one and the soil had a remarkably high supporting strength.
That is, from the experiment, it was found that the supporting strength of the soil can be improved by supplying the soil with crushed scallop shells and microorganisms having a size corresponding to the size of the soil particles in the soil.

The powdery scallop shell crushed product used in the experiment has a particle size of 0.106 mm to 0.005 mm, which is compared with the medium-grain scallop shell crushed product and the coarse-grained (fragment-like) scallop shell crushed product. Since it is presumed that a large amount of powder having a particle size smaller than the upper limit of 0.074 mm of the particle size of red soil is contained, powdery scallop shell crushed matter easily enters between the particles of red soil, and between the particles of red soil. It is presumed that as the bond became stronger, the entire red soil became one and solidified, resulting in a soil with extremely high supporting strength.

In particular, by adopting a method of supplying unfired crushed shells and microorganisms having a size corresponding to the size of soil particles of the soil to the soil, a remarkably excellent soil improvement effect capable of significantly improving the supporting strength can be obtained. It turned out to be obtained.
For example, supplying powdered scallop shell crushed material having a particle size of 0.106 mm to 0.005 mm to red soil which is clay having a particle size of about 0.074 mm to 0.005 mm, that is, grains of soil particles in the soil. By supplying crushed scallop shells with a size smaller than the diameter and microorganisms to red soil (soil), powdered scallop crushed products can easily enter between the particles of red soil, and the bond between the particles of red soil becomes stronger. Therefore, it was found that a remarkably excellent soil improvement effect capable of significantly improving the supporting strength can be obtained.

On the other hand, in the test body "red clay + sail (medium)" and the test body "red clay + sail (rough)", the particle size of the soil particles of red clay and the diameter of the scallop shell crushed material are significantly different.
That is, the distance between the red clay and the crushed scallop shell is large and the arrangement is disjointed. For this reason, it is probable that the bond between the red clay and the crushed scallop shell was weakened, and the supporting strength could not be obtained.

Therefore, from the experiment, it was found that the supporting strength of the soil can be improved by supplying the soil with crushed scallop shells having a size smaller than the particle size of the soil particles of the soil and microorganisms.

In other words, when the soil is clayey soil, the supporting strength of the clayey soil can be improved by supplying powdered scallop shell crushed material and microorganisms to the clayey soil, and the soil improvement effect can be achieved. Was found to be obtained.

1 Slope protection layer, 2 Slope, 4 Shell crushed solidified layer, 5 Sediment layer.

Claims (4)

A slope protective layer formed by supplying crushed shells obtained by crushing unfired shells and microorganisms to the slope. A slope protection method characterized in that crushed shells obtained by crushing unbaked shells and microorganisms are supplied to the slope. The slope protection method according to claim 2, wherein a crushed scallop shell is used as the crushed shell. The slope is a slope formed by embankment, and the embankment is constructed by alternately laminating a solidified layer of crushed shells formed by supplying crushed shells and microorganisms and a layer of earth and sand. The slope protection method according to claim 2 or 3, characterized in that.

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