JP2003146724A - Spray concrete layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spray concrete layer having high strength and high surface density. SOLUTION: Water is added to a mixture containing aggregate to be a hard granulated material of oxidized slag of an electric furnace, which is reformed by quenching, and water-hardenable inorganic material powder and the resultant mixture is sprayed onto a base surface and cured to form the spray concrete layer. The hard granulated material of oxidized slag of the electric furnace, which is reformed by quenching and used as aggregate in the spray concrete layer, is high in hardness, since its matrix has Mohs' hardness of nearly 6 and its mineral phase has Mohs' hardness of nearly 8, and heavy in weight, since its specific gravity is 3.3-4.1.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to, for example, a slope of a road,
The present invention relates to a concrete layer mainly formed on a sloping foundation surface such as a cliff, a riverbank, and a bank of a pond, and the concrete layer includes a solid concrete layer and a porous concrete layer.

[0002]

2. Description of the Related Art Conventionally, natural aggregates such as crushed stone, crushed stone, gravel and sand have been used as aggregates in this type of concrete layer.

[0003]

However, these natural aggregates have low hardness, are easily crushed, and are lightweight, so that a concrete layer having high strength and high areal density cannot be obtained.

[0004]

[Means for Solving the Problems] As a means for solving the above-mentioned conventional problems, the present invention provides an aggregate which is a hard electric furnace oxidizing slag granular material which has been subjected to a quenching reforming treatment, and a hydraulic inorganic material powder. Provide a sprayed concrete layer formed by adding water to the containing mixture and spray-curing it on the base surface. Further, in the present invention, a coarse aggregate 1 which is a hard electric furnace oxidizing slag granular material having a particle size of 5 to 13 mm and subjected to a quenching reforming treatment
00 parts by weight, 60 to 110 parts by weight of fine aggregate having a particle size of 5 mm or less, 20 to 70 parts by weight of hydraulic inorganic material powder, water reducing agent 0 to
A solid sprayed concrete layer formed by adding water to a mixture containing 30 parts by weight and 1.0-6.0 parts by weight of a quick-setting agent and spray-curing the base surface, and a particle size of 5- 100 parts by weight of coarse aggregate which is a hard electric furnace oxidation slag granule having a 13 mm quench and reforming treatment, 100 to 400 parts by weight of fine aggregate having a particle size of 5 mm or less, and hydraulic inorganic material powder 10
~ 60 parts by weight, 0 to 30 parts by weight of a water reducing agent, and 1.0 to 6.0 parts by weight of a quick-setting agent are added to the mixture to form a porous spray formed by spray-curing the base surface with water. 100 parts by weight of a coarse aggregate which is a concrete electric layer or a hard electric furnace oxidizing slag granular material having a particle size of 2.5 to 5 mm and which has been subjected to a quenching reforming treatment, 10 to 60 parts by weight of a hydraulic inorganic material powder, and a water reducing agent of 0 to 30. Parts by weight, and quick-setting agent 1.0-
A porous sprayed concrete layer formed by adding water to a mixture containing 6.0 parts by weight and spray-curing the base surface is provided. The present invention is particularly useful when the foundation is a sloping ground.

[0005]

The electric furnace oxidized slag granules of the present invention have a structure in which the mineral phase is dispersed in the matrix of the slag component. However, when the quenching reforming treatment is performed, the matrix of the slag component also has a Mohs hardness of about 6, Since the mineral phase has a Mohs hardness of about 8, it has high wear resistance. The mineral phase consists of iron-based minerals such as magnetite and iron chromite. In the case of water granulated slag, the mineral phase is projected on the surface to form fine irregularities, and in the case of ground slag, fine irregularities are also present on the surface because it breaks at the boundary between the matrix of the slag component and the mineral phase. It is formed.

As described above, according to the present invention, since fine irregularities are formed on the surface of the electric furnace oxidation slag granules, the hydraulic inorganic material as a binder is easily bited into, the solidity is improved, and a small amount of hydraulic inorganic material is used. Even if a material is used, the electric furnace oxidation slag granules are firmly bound and a high-strength concrete layer is obtained. Further, the electric furnace oxidation slag granules have a specific gravity of 3.3 to 4.1 and a large weight, and when this is used, the concrete layer has an excellent vibration damping property due to the weight effect, a sound insulating property, It also has excellent sound absorption, and has a high Young's modulus to improve bending strength. Furthermore, since the refractory degree of the electric furnace oxidized slag granules is about 1100 ° C., the concrete layer has excellent fire resistance.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below. [Electric Furnace Oxidized Slag Granules] The electric furnace oxidized slag referred to in the present invention is usually 10 to 26% by weight of CaO and 8 to _{2 of} SiO _2.
2% by weight, MnO 4 to 7% by weight, MgO 2 to 8% by weight,
Fe O 13 to 32% by weight, Fe ₂ O ₃ 9 to 45% by weight, A
l ₂ O ₃ 4 to 16 wt%, Cr ₂ O ₃ containing about 1 to 4 wt%, further Ti O ₂ from .25 to .70% by weight as a minor component, P ₂ O ₅ 0.15 to 0.50 % By weight, S0.00
It contains about 5 to 0.085% by weight and about 20 to 45% by weight of Fe for obtaining a stable mineral composition. It does not contain clay, organic impurities or salt contained in natural aggregate components at all. Free of stable free lime, free magnesia or minerals.

The electric furnace oxidation slag has a high specific gravity.
Therefore, if desired, high specific gravity metal powder or high specific gravity metal oxide
It may be added. The above-mentioned high specific gravity metal powder means iron or nickel.
Kell, cobalt, chromium, molybdenum, copper, lead, zinc,
For example, powder of alloy such as stainless steel,
Is 7 g / cm ³Above, the particle size should be less than 50μm
Good

As the high specific gravity metal oxide, there is an oxide of the high specific gravity metal. Further, as the high-specific-gravity oxide powder that can be used in the present invention, there is scale powder generated when the steel material is melt-cut. Such scale powder is substantially spherical and is ferrite, and can have the same function as that of the electric furnace oxidation slag granules. Further, other metal oxides such as calcium oxide and silicon oxide may be added to the electric furnace oxidation slag in order to adjust the basicity.

There are two methods for granulating the above-mentioned electric furnace oxidation slag to produce granules: a water granulation method and a crushing method. In the water granulation method, the melt of the electric furnace oxidation slag is poured into a high speed rotating bladed drum, the melt is crushed and granulated by the bladed drum, and the granulated melt is in a water mist atmosphere. The method of quenching reforming treatment is adopted. A plurality of bladed drums may be arranged to carry out crushing granulation in a plurality of stages. The granules of the electric furnace oxidation slag thus obtained usually have a particle size of 5 mm or less, and those having a particle size of 2.5 mm or less are substantially spherical, and high specific gravity metal powder and high specific gravity metal oxide are added. If not, the specific gravity is 3.
It is in the range of 3 to 4.1, has no defects such as cracks on the surface, has fine irregularities due to the mineral phase protruding on the surface, and is composed of or includes a hollow structure. .

In the crushing method, the electric furnace oxidation slag is cast in a molten state into a heat-resistant container to a predetermined thickness, and water is poured from above to perform a rapid reforming treatment.
In this case, if the thickness of the slag melt in the heat-resistant container is too small, it tends to be hardened by natural cooling (gradual cooling) before adding water, and there is a possibility that the desired hardness cannot be obtained.
If the thickness is too large, the water will suddenly become steam when sprinkled with water, and there is a risk of steam explosion. The preferred slag melt thickness is 80 mm to 120 mm.

When sprinkling water, it is desirable to prevent water from accumulating on the surface of the slag melt of the slag melt in the heat-resistant container. Too much water should be sprinkled on the surface of the slag melt. It becomes impossible to expect a quenching effect due to the latent heat of vaporization of water that accumulates. The amount of water is 1 slag melt
About 200 to 400 liters per second is desirable per ton. The slag melt is rapidly hardened by the rapid cooling, but at this time, the slag raw mass having a diameter of about the thickness of the slag melt in the container is obtained by self-crushing.

The raw slag mass is crushed by a crusher and further crushed by a crusher. By the above pulverization, the slag mass breaks at the boundary between the matrix of the slag component and the mineral phase, and fine irregularities are formed on the surface. The crushed material is roughly classified by a coarse sieving machine or the like, and further finely classified by a crushing machine or the like to obtain 5-2.
5 mm, preferably 5 to 20 mm of coarse aggregate, 5 to 13 mm of particle size, preferably 5 to 10 mm of coarse aggregate, 2.5 to 5 mm of coarse aggregate, and fine aggregate of 5 mm or less.

The above-mentioned crushing and crushing may be carried out while the raw slag mass is wet with water, or the slag raw mass may be dried and subjected to the steps after the crushing, or the slag raw mass may be used. May be crushed and then dried to carry out the steps after crushing. In the classification step, it is desirable that the residue that does not pass through the sieve be returned to the crushing step. The specific gravity of the granules thus obtained is in the range of 3.3 to 4.1, like the granulated product.

[Hydraulic Inorganic Material] Examples of the hydraulic inorganic material used in the present invention include cements such as Portland cement, alumina cement, blast furnace cement and the like, or blast furnace quenched slag fine powder, electric furnace quenched reduced slag fine powder, Mixed powders such as silica sand, silica stone powder, silica fume, blast furnace slag fine powder, fly ash, silas balloon, perlite, bentonite, diatomaceous earth and the like are available.

[Fine aggregate] The fine aggregate used in the present invention has a particle size of 5 mm or less. As such a fine aggregate, for example, the particle size of the electric furnace oxidation slag granules is 5 mm.
The following, sand with a particle size of 5 mm or less is used.

[Coarse Aggregate] In the present invention, a particle size of 5 to 25 is used instead of a part of the coarse aggregate composed of the electric furnace oxidized slag particles.
mm or 2.5 to 5 mm of crushed stone, coarse aggregate such as gravel may be used.

[Water-Reducing Agent] Examples of the water-reducing agent used in the present invention include AE water-reducing agents and high-performance water-reducing agents.

[Quick-setting agent] In the present invention, a quick-setting agent is used for rapidly hardening the sprayed concrete layer. Examples of such a quick-setting agent include calcium chloride, magnesium sulfate, aluminum sulfate, polyaluminum chloride and the like.

[Solid concrete spraying compound] In the solid concrete spraying compound, 100 parts by weight of coarse aggregate, which is a hard electric furnace oxidizing slag granule having a particle size of 5 to 13 mm and which has been subjected to a quenching reforming treatment, 60 to 110 parts by weight of fine aggregate having a particle size of 5 mm or less, 20 to 70 parts by weight of hydraulic inorganic material powder, water reducing agent 0
Water is added to the mixture containing .about.30 parts by weight, and 1.0-6.0 parts by weight of the quick-setting agent. The amount of water added is usually 10
It is about 4 to 7 parts by weight with respect to 0 parts by weight.

[Porous Concrete Spraying Mixture] In the porous concrete spraying mix, the particle size is 5 to 13
100 parts by weight of coarse aggregate which is a hard electric furnace oxidation slag granular material subjected to quenching reforming treatment of 100 mm, and fine aggregate 100 having a particle size of 5 mm or less
.About.400 parts by weight, hydraulic inorganic material powder 10 to 60 parts by weight, water reducing agent 0 to 30 parts by weight, and quick-setting agent 1.0 to 6.
Mixture containing 0 parts by weight, or 100 parts by weight of coarse aggregate, which is a hard electric furnace oxidation slag granule having a particle size of 2.5 to 5 mm and subjected to quenching reforming, 10 to 60 parts by weight of hydraulic inorganic material powder, and reduced water Agent 0 to 30 parts by weight, and quick-setting agent 1.0 to 6.
Water is added to the mixture containing 0 parts by weight. The amount of water added is usually about 4 to 7 parts by weight per 100 parts by weight of the mixture.

Spraying The above formulation is sprayed onto the base with a spray gun. As the foundation, the slope of the road,
Examples include sloping ground such as cliffs, riverbanks, and levee bodies. The spray formulation of the present invention is sprayed onto such a sloped ground surface.
The sprayed formulation cures to prevent ground collapse due to high strength and mass effects and the like. In particular, when a porous concrete layer is formed on the surface of a riverbank or a pond embankment, water can pass through the porous concrete layer from the inside or the outside, and plants can grow. Further, there are buildings and structures as the foundation, and by spraying on the outer surfaces or damaged parts of buildings and structures, fire resistance, sound insulation / vibration resistance, abrasion resistance, slip resistance, etc. are imparted to the structures and construction. If there is a damaged part, reinforce it.

[Example 1] (Compound concrete mixing) As the coarse aggregate, a hard electric furnace oxidation slag granular material having a particle size of 5 to 13 mm and subjected to a quenching reforming treatment is used. As the fine aggregate, the above-mentioned electric furnace oxidation slag granules having a particle size of 5 mm or less are used. The following spray formulations are prepared using the above coarse and fine aggregates. Water 160kg, Portland cement 320k
g, coarse aggregate 1028 kg, fine aggregate 1542 kg, quick setting agent 20 k
g, a high-performance AE water reducing agent 3.2 kg, and a thickener 6.4 kg were mixed to make 1 m ³ . Spray the above formulation onto the base and at room temperature 3
Table 1 shows the results of measuring the physical properties of the concrete layer after standing for one day.

[Comparative Example 1] Grain size as coarse aggregate 5 to 13 mm
The following spray formulations were prepared using crushed stones of No. 1 and sand having a particle size of 5 mm or less as fine aggregate. Water 160kg, Portland cement 320kg, coarse aggregate 702kg, fine aggregate 1
052 kg, quick-setting agent 20 kg, and high-performance AE water reducing agent 3.2 kg were mixed to make 1 m ³ . In the above composition, the volume percentages of the coarse aggregate and the fine aggregate are set to be the same as in Example 1. Table 1 shows the results of measuring the physical properties of the concrete layer after spraying the above mixture on a foundation and leaving it to stand at room temperature for 3 days.

[0025]

[Table 1]

As can be seen from Table 1, the shotcrete concrete layer of Example 1 has remarkably large compressive strength and Young's modulus as well as the unit volume mass as compared with Comparative Example 1 using natural aggregate. And it is recognized that the material loss is small.

Example 2 (Compounding Porous Concrete) As a coarse aggregate, a hard electric furnace oxidizing slag granular material having a particle size of 2.5 to 5 mm is used. The following spray formulations are prepared using the above coarse aggregate. Water 133kg, Portland cement 380kg, coarse aggregate 1950kg, quick-setting admixture 15kg, high performance A
E Water-reducing agent (2.0 kg) was mixed to make 1 m ³ . Table 2 shows the results of measuring the physical properties of the concrete layer after spraying the above composition on a foundation and leaving it to stand at room temperature for 3 days.

[Comparative Example 2] Particle diameter of 2.5 to 5 as coarse aggregate
Use mm hard sandstone crushed stone. The following spray formulations are prepared using the above coarse aggregate. 133 kg of water, 380 kg of Portland cement, 1246 kg of coarse aggregate, 15 k of quick setting agent
g and 2.0 kg of a high-performance AE water reducing agent were mixed to make 1 m ³ .
In the above composition, the volume% of the coarse aggregate is set to be the same as in Example 2. Table 2 shows the results of measuring the physical properties of the concrete layer after spraying the above composition on a foundation and leaving it to stand at room temperature for 3 days.

[0029]

[Table 2]

As shown in Table 2, the shotcrete concrete layer of Example 2 has a porosity equivalent to that of Comparative Example 2 using natural aggregate, but both the compressive strength and Young's modulus are remarkably large. It is recognized that the unit volume mass is also large and the material loss is small.

[0031]

According to the present invention, high strength and high areal density,
Provided is a shotcrete layer having excellent fire resistance, sound insulation, vibration control, wear resistance, and slip resistance.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Keiichi Tsuruyama             Aichi Prefecture, Kabu-gun, 14 Yamamura Large-scale horseback ground Nitta             Tame 62 Hoshino Sansho Co., Ltd. F-term (reference) 2D044 DC04                 4G012 PA04 PA29

Claims (5)

[Claims] 1. A mixture formed by adding aggregate, which is a hard electric furnace oxidation slag granule that has been subjected to a quenching reforming treatment, and a hydraulic inorganic material powder, to which water is added, and the mixture is spray-cured onto a base surface to be cured. Shotcrete layer characterized by 2. 100 parts by weight of coarse aggregate which is a hard electric furnace oxidation slag granular material having a particle size of 5 to 13 mm and which has been subjected to quenching reforming, 60 to 110 parts by weight of fine aggregate having a particle size of 5 mm or less, and a hydraulic inorganic material. Formed by adding water to a mixture containing 20 to 70 parts by weight of the material powder, 0 to 30 parts by weight of a water reducing agent, and 1.0 to 6.0 parts by weight of a quick-setting agent, and spray-curing the mixture on a base surface. Solid shotcrete layer characterized by 3. 100 parts by weight of coarse aggregate, which is a hard electric furnace oxidizing slag granule having a particle size of 5 to 13 mm and which has been subjected to quenching reforming, 100 to 400 parts by weight of fine aggregate having a particle size of 5 mm or less, and a hydraulic inorganic material. Formed by adding water to a mixture containing 10 to 60 parts by weight of material powder, 0 to 30 parts by weight of a water-reducing agent, and 1.0 to 6.0 parts by weight of a quick-setting agent, and spray-curing the surface of the base. Porous shotcrete layer characterized by 4. 100 parts by weight of coarse aggregate which is a hard electric furnace oxidizing slag granule having a particle size of 2.5 to 5 mm and which has been subjected to a quenching reforming treatment,
Hydraulic inorganic material powder 10 to 60 parts by weight, water reducing agent 0 to 30
A porous sprayed concrete layer formed by adding water to a mixture containing 1 part by weight and 1.0-6.0 parts by weight of a quick-setting agent, and spray-curing the mixture onto a base surface. 5. The shotcrete layer according to claim 1, wherein the foundation is a sloping ground.