JPH05195537A - Formation of water-resistant growing base - Google Patents

Abstract

PURPOSE:To contrive the growth of plants in water and on the ground area to be immersed in water for a given period by a method in which fine particle- mixed agglomerates consisting of water, air, and clay containing fertilizer are formed and covered with a specific water-resistant gel substance. CONSTITUTION:A sludgy mixture is formed from viscous soil such as clay, fertilizers, coagulants such as anionic polyacrylamide, and water. The sludgy mixture is sprayed onto the slope 2 of the ground 1 to be immersed in water seasonably, such as dam, where the mixture undergoes a higher agglomerating reaction in the presence of air as catalyst to form dehydrated plastic agglomerates 4 and a vegetating base 3 with voids 5. A mixed aqueous solution of an alkali silicate and Na-type silica sol colloidal silica or any one of the aqueous solutions and a hardener aqueous solution of a bicarbonate are sprayed onto the surface of the base 3 by a two-liquid sprayer to cover the hydrophilic agglomerates with the silica gel compounds. The run-off of the base can thus be prevented by easing the impact of water during water-immersing period and the drying of the base during non-immersing period can also be prevented. The vegetation by growth of plants can be attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a vegetation foundation for a slope in civil engineering work, etc. More specifically, it is submerged for a long period of time depending on the season, such as the slope of a dam.
The present invention relates to a construction method for measuring afforestation by providing a stable water-inundation resistant growth base capable of growing water and waterside plants on a slope exposed as a bare slope during a drought season.

[0002]

2. Description of the Related Art A mud-like material is sprayed with a hydrophobic nozzle and air onto a slope, etc., which has been made bare due to development work or disasters (hereinafter also referred to as a slope) with a spray nozzle to form a plant growth base. The means for restoring greening is well known, and this is disclosed in Japanese Patent Publication No. 2-26932. This is a method suitable for plant growth, in which a viscous soil having a water retaining and fertilizing effect suitable for plant growth is used for plant growth, that is, a method of spraying the soil structure on the slope, etc. Creation of a sufficiently thick base has been achieved.

Further, in JP-A-1-310019, thin continuous fibers are three-dimensionally mixed into the substrate in order to prevent the substrate formed by the above method from being eroded by rainwater or the like. .. This prevents the greening base material from falling off on the slope, creating an environment suitable for plant growth such as water retention, drainage, breathability and moisture retention in the base, increasing the rooting effect of the plant and greening. Being promoted.

[0004]

The slope formed by the construction of the dam is normally flooded for about 200 days a year when the water volume is high, but the drought around June, July, August, September and October. At the end of the year, a huge area of slope becomes bare land due to the water level drop of 30m, which damages the scenery of the summer dam during the tourist season. On the other hand, from the standpoint of placing importance on environmental protection, selection of waterlogging waterside plants is currently being carried out in order to green the bare land.

However, the development of a water-infiltration-resistant growth base for growing these plants has not yet been carried out. In terms of the slopes obtained by the construction method described in connection with the above-mentioned prior art, the following points are incomplete as a growth base for slopes that are submerged and flooded for a long period of time. (1) A polymer flocculant that is entangled with soil particles to form an aggregated structure causes the shrinkage caused by adjusting the degree of hydrolysis of the polymer to gradually expand due to the adjustment of the degree of hydrolysis of the polymer when immersed in water for a long time ..

(2) The clay, which is the base of the base, becomes rich when flooded and weakens the entanglement with the polymer. (3) Thin continuous fibers have a reinforcing effect on land when they are in close contact with the base, but in water, the fibers loosen and float, which reduces the effect by half. For the above reasons, the conventional plant growth foundation by the greening foundation construction method is not suitable for slopes that have been flooded for a long time.

[0007] Further, generally considered for the submerged slope is sizing with a water-resistant binder (bonding agent) such as a resin such as cement or acrylic, which solidifies the growth base. As a result, the germination and growth of plants will be extremely inhibited. In view of the above circumstances, in the present invention, a water-resistant and water-insoluble growth base based on clay capable of holding water and air and fertilizer components necessary for plant growth is formed on a slope that is submerged for a certain period of time. The purpose is to do.

[0008]

[Means for Solving the Problems] In order to achieve the above object, in the present invention, sodium silicate or sodium silicate is used instead of gluing materials used as vegetation base materials, mainly materials containing soil fine particles such as clay. An aqueous solution of a water-resistant gel material such as an alkali metal silicate composed of potassium silicate (hereinafter referred to as water glass) or colloidal silica (hereinafter referred to as silica sol) is mixed or reacted alone with a curing agent. By doing so, it was decided to form a mesh structure that encloses the vegetation base material.

Generally, water glass (Na ₂ O.nSiO ₂
xH ₂ O) is injected into soft ground as a soil stabilizer,
It is used for the purpose of temporarily hardening and stabilizing, and it is a cause of weakening by injecting water glass to the hardening object, for example, when preventing water leakage from the tunnel inner wall. It is used to stabilize and harden the soil by, for example, encapsulating the water contained therein and forming a gelation product that surrounds the water W to form a network structure G (hydrated gel) of gel as shown in FIG. ing.

In the present invention, utilizing the above properties,
As shown in Fig. 3, a mixture of soil fine particles such as clay (hereinafter referred to as soil) in the network structure G of the water-resistant gel product produced by adding the curing agent to the liquid mixture of water glass and silica sol or one of them. A three-dimensional water-containing gel by reacting the aggregated structure S formed by cross-linking and aggregating a material) with a polymer aggregating agent (hereinafter referred to as an aggregating agent) in a three-dimensional manner. Provided is a method for constructing a growth base for underwater and land plants, which is characterized in that a solid flocculent solid is produced to thereby form a vegetation base having water infiltration resistance.

[0011]

In the vegetation base formed by three-dimensionally enclosing the aggregated structure S in the water resistant gel material network structure G, the gel material network structure G is water resistant.
When the vegetation base is located below the submerged surface of a dam or the like, the impact on the aggregated structure S due to the flow and waves of water is mitigated, and the submerged growth base is not washed away and located above the submerged surface. Has a function of preventing the water from drying, and as a result, moisture, air and fertilizer components necessary for plant growth are retained in the agglomerated structure S on a slope which is submerged for a certain period of time.

[0012]

[First Embodiment] First, a first embodiment for forming a water-repellent vegetation base according to the present invention will be described. Japanese Patent Publication No. 2-26
According to the construction method disclosed in Japanese Patent No. 932, as shown in FIG. 1, a mud-like vegetation having a mixture content as shown in Table 1 is applied to a construction target surface (slope) 2 which is a slope of a natural ground 1. The base material A and the agglomerate B are sprayed with air by a spray nozzle to form a plant growth base 3.

[0013]

[Table 1]

That is, as a mud-like vegetation base material A consisting mainly of viscous soil and organic matter, a soil material A ₁ and fertilizer, a curing material A ₂ and a stabilizer A ₃ and fresh water (water) A ₄ are mixed, It is made into a mud in a predetermined concentration, pressure-fed by a slurry pump (not shown), discharged from a nozzle, and then mixed with a 0.2% aqueous solution of an aggregating agent B ₁ (anionic polyacrylic amide), and air is used as a catalyst. Target surface (slope) while performing higher aggregate reaction as
Spray on. The muddy vegetation base material A sprayed onto the slope 2 is subjected to a higher-order aggregate reaction to dehydrate excess water used for muddying, plasticize it, and form a higher-order aggregate. 4 is formed and is stably attached to the slope 2. The above is the above-mentioned Japanese Patent Publication 2-26
This is the same as the construction method disclosed in Japanese Patent No. 932.

The growth base 3 formed by the above-mentioned construction method has various large and small voids 5 and is stable with good permeability, and water permeates into the base 3 quickly even in rainwater. The surface of 3 does not almost flow down.

[0016]

[Table 2]

In this embodiment, the stabilizer C shown in Table 2 is sprayed on the surface 3a of the substrate 3 which is stable as described above together with the reactant D by a two-component spraying machine (not shown). ,
Naturally permeate into the base 3. At this time, the gelling time (the time during which the water glass or silica sol turns into a gel from the sol) is determined in consideration of the time required for both liquids C and D to sufficiently penetrate into the substrate 3, and the stabilizer C and the reactive agent corresponding thereto are determined. The blending ratio with D is determined as shown in Table 2, for example. In this
The silica sol C ₁ is cured with the curing agent D ₁ and the binder D ₂
This causes the silica sols to stick to each other.

However, according to this method, since the silica sol itself has a viscosity, it is difficult for the silica sol to penetrate deeply into the vegetation base 3, and the silica sol evenly penetrates into the base 3, as shown in FIG. As described above, it is not possible to expect that the hydrophilic clay aggregates S are reliably wrapped with the water-resistant silica sol-gel compound G. Therefore, in order to more reliably and uniformly form the network structure G of the water-resistant gelation product in the substrate 3, the following method was invented as the second embodiment.

The second embodiment is based on the Japanese Patent Publication No. 2-26932.
Stabilizer (silica sol) and reactive agent (hardening agent and adhesive) are mixed in the mud-like vegetation base material and the aggregating agent prepared by the greening foundation construction method shown in the publication, and mixed in the nozzle. However, it is a method of directly spraying on the slope 2 of the natural ground 1.

[0020]

[Table 3]

At this time, the muddy vegetation base material E and the agglomerate F,
Table 3 shows the content of the reagent H blended. As shown in FIG. 2, the muddy vegetation base material E is sprayed together with the agglomerate F, the reactant H and the fresh water I from the nozzle onto the slope 2 of the natural ground 1, and at this time, the agglomerate F is the muddy vegetation base. The material E is aggregated to form aggregates, and the reaction agent H
Is a stabilizer E ₃ (silica sol) that is gelled and aggregated to form a uniform water-resistant gel network structure G within the vegetation base where aggregates are formed.
To form.

Generally, water glass is strongly alkaline,
In the case of gelling this, a strongly acidic one is used as the reaction agent, and it is gelled by being neutralized. However, in the method of this example, in order to cause the aggregate reaction of the mud-like vegetation base material E, Agglomerating agent F (polyacrylic amide) composed of a polymer flocculant used (referred to as a hydrophobizing agent in Japanese Patent Publication No. 2-26932) does not react when biased toward strong acidity or strong alkalinity. There is. Therefore, in this embodiment, silica sol which gels with a reaction agent close to neutral is used as the stabilizer E ₃ instead of water glass.

Further, gelation for aggregating the muddy vegetation base 3
Gel time to gel gel time
Im is a gel by changing the concentration of each reactant
You can adjust the time. In the case of this embodiment,
Customer soil material E in Table 3₁And fertilizer, curing material E₂Tonidan
Clay suspended in water after reacting with granule F₁But
Entanglement agglomeration with a polymer agglomerate F. At this time
With water and stabilizer E₃Silica sol is a silica sol aqueous solution
And then this remaining water and stabilizer E ₃React with
Network structure of silica sol gelled by subsequent reaction with agent H
Structure (G) is made. In this way, the aggregate reaction first occurs.
The aggregated clay is turned into a mud as shown by the arrow in Fig. 2.
Water (silica sol aqueous solution) used for is dehydrated (hydrophobic),
Then, this water was encapsulated with silica sol to form a gel.
The aggregated structure S as shown in FIG.
Aggregate solids surrounded by the network structure G are generated, and
A vegetation base is created. In this embodiment, the former
The gel time for forming aggregates is about 3 seconds, and the latter silica sol is used as a gel.
It takes about 5 seconds for gelation to form aggregates like this.
Gel time and gel time that forms a network structure with silica sol
By shifting and more reliably than in the first embodiment
Plants with uniform water resistance and water retention of terrestrial plants
It is possible to create a growth base suitable for growing a product.
Each gel time depends on the concentration of each aqueous solution
It can be adjusted.

In the above-described examples, an example in which a silica sol aqueous solution is used alone as a gel material for gelation has been described, but the gel material is not limited to this. By using an aqueous solution of water glass or a mixed solution of water glass and silica sol and using a curing agent adapted to each, the aggregated structure S is wrapped with the water resistant gelation product G and the water resistant growth of water and land plants. It is possible to create a foundation.

[0025]

EFFECTS OF THE INVENTION According to the present invention, agglomerate solids in which agglomerated structures are three-dimensionally wrapped in a network structure of a water-resistant gelled product are produced, and a water-insoluble growth base is created, which results in vegetation. When the foundation is located below the flood surface such as a dam, the flow and impact of water on the aggregated structure is mitigated, there is no outflow of the foundation even in the water, and when the foundation is above the flood surface, the aggregate is aggregated. The functionalized structure has a function of preventing drying, whereby water, air and fertilizer components necessary for plant growth can be retained on a slope which is submerged for a certain period of time, thereby promoting greening of the submerged slope.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a submerged resistant growth base constructed according to a first embodiment.

FIG. 2 is a partial cross-sectional view of a submerged resistant growth base constructed according to a second embodiment.

FIG. 3 is a schematic view of an aggregated structure three-dimensionally wrapped by a gelled network structure.

FIG. 4 is a schematic diagram of water (hydrous gel) surrounded by a gelled network structure.

[Explanation of symbols]

 2 ... Slope 3 ... Vegetation base 4 ... Aggregate S ... Aggregate structure G ... Gelled network structure

Claims (1)

[Claims] 1. An aggregated structure (S) produced by aggregating a fine particle mixture with an aggregating agent, a mixed aqueous solution of an alkali metal silicate and colloidal silica, or the alkali metal silicate or the colloidal silica. A vegetation base is formed by a water-resistant aggregate solid that is reacted by being three-dimensionally wrapped with a water-resistant gelation product (G) produced by adding a curing agent to any one of the aqueous solutions of A method for constructing a growth base for underwater and land plants.