JPH0453211B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a greening base concrete construction method, and more particularly to a greening base concrete construction method with good vegetation that can be applied to steep slopes.

[Background of the Invention] A fiber soil greening step method is conventionally known as a greening infrastructure method for growing vegetation on a slope. This method involves applying fiber soil (a mixture of sandy soil, fibers, reinforcing materials, compound fertilizer, cement, seeds, water, etc.) in steps on soilless slopes such as bedrock surfaces, dumping sites, existing mortar, and concrete sprayed surfaces. This is a construction method that involves spraying to create a foundation and greening it.

However, the critical slope of this method is 1:0.5,
If the slope is higher than this, the strength of the base material will be weak and it will flow out. In addition, in the case of a steep, smooth slope, it is necessary to fix the base material by fixing a wire mesh to the slope with anchor pins and placing horizontal wedges with mortar at regular intervals to avoid slippage, which is complicated. There is a certain drawback. Furthermore, it can be difficult to maintain plants on steep slopes, so when introducing plants, it may be possible to cut into the slope, but this has the disadvantage of being time-consuming.

A slope greening method by spraying permeable concrete is known as a construction method that solves the runner-up problem of the above-mentioned fiber soil greening step method. In this construction method, porous water-permeable concrete containing more coarse aggregate than fine aggregate is sprayed onto the slope, and alkaline components on the surface of the concrete are washed out by penetrating water and forced watering. This is a construction method that enables the reinforcement and greening of slopes using shotcrete by spraying a mixture of bentonite, adhesive, etc. onto the slope, and growing plants by supplying water with seepage or seepage water.

However, if the amount of fine aggregate is reduced, there will be less mortar or milk during spraying, and there will be less to adhere to, so the kinetic energy of the coarse aggregate cannot be absorbed by spraying, and there will be a lot of rebound, making it difficult to create water-permeable concrete. The disadvantage is that it is difficult to Furthermore, even if the spraying device and nozzle device are improved, when spraying mortar or materials with a small milk content, there is a problem that cannot be solved in principle because there is a lot of rebound and it is difficult to spray. Furthermore, washing concrete using forced water sprinkling is difficult to clean on slopes due to scaffolding conditions, water supply, and other work conditions, and has the drawback of being labor-intensive. In addition, the surface of permeable concrete contains vegetation seeds, nutrients, bentonite,
Even if you spray greening base materials such as adhesive materials, if the slope is gentle, rainwater will not run off, but if the slope is steep, it will run off. Furthermore, even if a greening base material is sprayed onto water-permeable concrete, only a small amount of it will penetrate into the gaps, and the thickness of the base must be increased, which has the drawback of being uneconomical. In addition, since water is retained only between aggregates in permeable concrete, free water such as rainwater and groundwater flows out due to gravity and has the disadvantage that it does not have a water retaining function.

As a construction method to solve this drawback, JP-A-57-
No. 58727 discloses a method of using mulch such as beet moss as aggregate, but it has the disadvantage that the thickness of the vegetation base shrinks after spraying.

For this reason, JP-A-59-102018 discloses a method of spraying a slurry-like vegetation base material containing Kanuma soil as an aggregate instead of beet moss, and JP-A-52-132502 also discloses a construction method in which a slurry-like vegetation base material containing Kanuma soil as an aggregate is sprayed. A construction method is disclosed in which soil particles containing coarse particles such as soil are mixed with cement, Kanuma soil or the like is used as aggregate, and the slurry is sprayed.

However, in the method of JP-A-52-132502, the base treatment layer is sprayed with a slurry mixture and hardened.
Since it is made of a mixture of Kanuma soil, etc. and cement, the soil particles dissolve into the hardened cement and weaken the strength between the hardened cement components, resulting in a very weak base layer and a steep slope slope. If there is, it has the disadvantage of collapsing and leaking out. In addition, slurry has poor water permeability and low water retention capacity, which is a drawback from a vegetation perspective. Furthermore, when a slurry made by mixing coarse particles, cement, and water is sprayed and hardened, the hardness of the soil varies depending on the amount of cement, which has the disadvantage that plant roots cannot penetrate it. In addition, the base layer uses coarse particles to create an uneven surface and adhere to slopes such as bedrock, and is only used to stabilize artificial soil that is constructed on top of the base layer. The disadvantage is that the base layer itself does not serve as a greening base.

Furthermore, in JP-A No. 59-102018, even if Kanuma soil etc. treated with a surfactant is used, it is inevitable that Kanuma soil etc. will have a negative effect on the adhesive performance of concrete because it is used in the form of a slurry. Since Kanuma soil does not exist independently, it has the disadvantage that it does not function as a greening base.

[Object of the Invention] Therefore, an object of the present invention is to provide a greening base concrete construction method that can permanently maintain a greening base even if the slope is steep and smooth.

Another object of the present invention is to improve the adhesive strength of concrete by having part or most of the granular solid materials that serve as the greening base exist independently and continuously in contact with each other inside the concrete structure. It is an object of the present invention to provide a greening base concrete construction method in which granular solid materials independently form a greening base without adversely affecting the environment.

Still another object of the present invention is to provide a greening base concrete construction method that promotes penetration of plant roots, has water retention properties, and contains nutrients required by plants.

[Means for Solving the Problems] The present inventor has made extensive studies to achieve the above object, and as a result, has arrived at the present invention.

That is, the greening base concrete construction method according to the present invention includes cement, sand, gravel, and granular solid material having the following composition that becomes a greening base by containing water;
A predetermined amount of the mixture is blended to obtain a blend, and the blend is used as dry mix, which is then pumped in a fixed amount with a spray machine.Water is then added and mixed to the pumped dry mix at the tip of the spray machine, before the granular solid material is eluted. When sprayed onto a slope, many granular solid materials exist inside a concrete structure made of cement, sand, and gravel without being eluted, with some or most of them being independent and some of them being in contact with each other in a continuous state. It is characterized by forming a greening base.

(Composition of granular solid material) Soil granules containing clay minerals, bark compost, fibers, chemical fertilizers, perlite adhesives, and adhesives are kneaded, shaped, dried, and solidified to form sand and gravel. Granular solid material with hardness, particle size, and shape that can replace some parts.

[Specific Configuration] The concrete construction method for greening base of the present invention will be explained in detail below.

The present invention first involves cement, sand, gravel, and a granular solid material that has a hardness, particle size, and shape that can replace a part of the sand and gravel, and that becomes a greening base when it contains moisture. A predetermined amount of additives to be added according to the conditions are blended to obtain a blend, and the blend is mixed in a dry mix, that is, a fixed amount is pumped by a spray machine in a dry mixed state.

In the present invention, the granular solid material is a circular shape having a diameter of about 5 mm to 15 mm, which can be used as a substitute for sand and gravel.
Various shapes such as oval are used.

Further, the granular solid material has a hardness that can be used as a substitute for a part of sand and gravel, but specifically, a material having a certain hardness that does not lose its shape during dry mixing or blowing and pressure feeding is used.

Furthermore, the granular solid material is one that does not adversely affect the concrete components of the shotcrete even if it softens over time when it absorbs moisture, and that also facilitates the penetration of plant roots.

Furthermore, the granular solid material is a component of soil grains that becomes the foundation for greening when it absorbs water.In other words, it has good water retention, provides moisture to plants, and contains nutrients necessary for plants. , suitable for vegetation. The soil grain components mainly include clay minerals, bark compost, fibers, chemical fertilizers, perlite adhesives, adhesives, and the like.

The granular solid material of the present invention is obtained by kneading this soil particle component, shaping it into a certain shape, drying and solidifying it, and the particle size is moderately distributed between 5 and 15 mm. Since the granular solid material of the present invention can be obtained through the processes of kneading, shaping, drying, and solidification, or a process equivalent to these processes, there is no need for a technique that uses ceramics alone that does not involve these processes. The technical philosophy is different from that.

In the present invention, various known cements can be used as the cement, such as Portland cement.

In addition to the above-mentioned cement, sand, gravel, and granular solid materials, the composition of the present invention may optionally contain reinforcing materials such as fibers as additives.

The mixing ratio of the above components is cement: second: gravel: granular solid material = 0.1 parts by volume: 0.3 to 0.8 parts by volume: 0.1 to 0.4
Parts by volume: 0.1 to 0.5 parts by volume, more preferably 0.1 parts by volume: 0.4 to 0.6 parts by volume, and 0.1 to 0.3 parts by volume: 0.2 to 0.4 parts by volume.

In the present invention, as is clear from the above blending ratio, granular solid material is used as a partial substitute for sand and gravel.

The method of dry-mixing the above-mentioned composition is not limited, and any known method can be used, and the dry-mixed composition is fed in a fixed amount using a known spraying machine in a dry state.

Next, water to which additives have been added as necessary is added to and mixed with the dry mixes fed under constant pressure at the tip of the nozzle of the sprayer, and the mixture is sprayed onto the slope. As additives, AE agents, quick setting agents, polymer resins (for example, SBR latex, methyl cellulose, etc.) are used.

At this time, since water was added to and mixed with the dry mix at the time of spraying, the granular solid material did not dissolve into the cement milk, and the granular solid material was in a dry state, that is, existed independently without being eluted. Can be sprayed in any condition.

By the above-mentioned spraying, a part or most of the granular solid materials are independent and some of them are in contact with each other to form a continuous greening base inside the concrete structure made of cement, sand, and gravel.

The above is a so-called dry method in which a mixture of cement, granular solid materials, etc. is dry mixed and then mixed with water, but the following wet method may also be considered.

That is, a predetermined amount of cement, sand, gravel, granular solid material that does not soften or dissolve even when placed in water until concrete is poured, water, and additives as necessary are mixed and mixed together. In this method, a mixture is obtained using a spraying machine, and the mixture is sprayed using a spraying machine to form a greening base, similar to the above-mentioned cyclic method. In this method, too, the particulate solid material exists independently in the wet mix.

The granular solid materials that do not soften or dissolve even when placed in water until concrete is poured are mixed with soil components such as clay minerals, bark compost, fibers, chemical fertilizers, perlite, adhesives, and adhesives. It can be obtained by applying a poorly water-soluble coating material to the product, which is shaped into a certain shape, dried, and solidified.

[Example] Example 1 (Dry method) Cement 0.15 m ³ , sand 0.4 m ³ , gravel 0.1 m ³ , granular solid material of the present invention 0.35 m ³ (Hardness is about that of sand, size is between sand and gravel) 0.21 m ³ of water and 2.4 kg/m ³ of AE agent are added and mixed, and sprayed onto a steep slope. A green base concrete with a thickness of 150 mm was formed.

The compressive strength of this base is 80Kg/cm ² and the permeability coefficient is 1×
It was 10 ^-3 .

The compressive strength was determined using a 100 mm square specimen, and the permeability coefficient was determined by a displacement water level permeability test.

After leaving it for one month, white clover was sprayed together with soil to germinate the plant.

As a result, the germination rate of white clover was 7.
It was 25% on the 14th, 45% on the 14th, and 65% on the 28th.

Reference example 1 (wet method) Cement 0.15m ² , sand 0.4m ² , gravel 0.1m ² , granular solid material with poorly water-soluble coating 0.35m ² ,
2.4 kg/m ² of AE agent and 0.26 m ² of water were mixed together and sprayed using a spraying machine to form a green base concrete with a thickness of 150 mm.

Compressive strength is 70Kg/cm ² , hydraulic conductivity is 10 ^-3 cm/sec
It was hot.

After leaving it for one month, apply white clover to Example 1.
The germination rate of white clover was 25% in 7 days, 40% in 14 days, and 60% in 28 days.
It was %.

Comparative Example 1 In Example 1, no granular solid material was used, and 0.1% of sand was used.
The spraying was carried out in the same manner except that the area was changed to 0.7 m 2 of gravel and 0.7 m ^{2 of} gravel.

However, it did not adhere stably to the slope, and most of the gravel bounced back.

Comparative Example 2 The same procedure as Example 1 was carried out except that the granular solid material was replaced with non-softening Kanuma soil. However, the Kanuma soil was pulverized during dry mixing, and was further accelerated and pulverized during the pumping process, resulting in the generation of dust. When it gets mixed into the concrete, its strength decreases and there is a marked tendency for it to fall off, resulting in extremely brittle concrete.

In addition, when vegetation was grown in the same manner as in Example 1, the germination rate of white clover was 2% in 7 days and 7% in 14 days.
%, it was 12% in 18 days, which was quite bad. This is thought to be due to the fact that granular solid materials cannot exist independently, and fine particles are dispersed in the concrete, causing alkaline components in the concrete to elute, and there is no vegetation base.

[Operations and Effects of the Invention] According to the present invention, even when the slope is steep, the hardened material such as cement milk is formed so that the granular solid material serving as the greening base is wrapped, so that the greening base can be made permanent. is maintained.

In addition, in the case of a hardened product made by mixing soil particles such as Kanuma soil with cement milk or mortar, the soil particles such as Kanuma soil dissolve into the hardened cement product, weakening the strength between the cement hardening components, and the structure Although it is not possible as a product, the present invention sprays the granular solid material into cement milk or mortar before dissolving it, so that some or most of the granular solid material is independent and some of the solid material is isolated inside the concrete structure. By existing in a continuous state in contact with each other, they can function as a structure.

Furthermore, when a slurry made by mixing granular solid material and cement is sprayed and hardened, the hardness of the soil varies depending on the amount of cement, making it impossible for plant roots to penetrate, but in the present invention, the granular solid material is independent. In addition, by existing in a continuous state where some parts are in contact with each other, it can serve as a greening base.

In addition, the granular solid materials are independent and bonded to each other to promote penetration of plant roots, have water retention properties, and contain nutrients required by plants.

Because granular solid materials have the property of being easily mixed with alkaline components in concrete components, adding polymeric resins to concrete or added water prevents the elution of alkalinity and increases the resistance of concrete to freezing and thawing. can be increased.

Claims (1)

[Claims] 1. A granular solid material having the following composition that becomes a greening base by containing cement, sand, gravel, and water;
A predetermined amount of the mixture is blended to obtain a mixture, the mixture is dry mixed and a fixed amount is fed by a spraying machine, and then water is added and mixed to the fed dry mix at the tip of the spraying machine, and the granular solid material is eluted. The granular solid materials are sprayed onto the slope beforehand, and a large number of granular solid materials exist in a continuous state, with some or most of them independent and some in contact with each other, without being leached into the concrete structure made of cement, sand, and gravel. A greening base concrete construction method characterized by forming a greening base. (Composition of granular solid material) Soil granules containing clay minerals, bark compost, fibers, chemical fertilizers, perlite adhesives, and adhesives are kneaded, shaped, dried, and assimilated to form sand and gravel. Granular solid material with hardness, particle size, and shape that can replace some parts.