JPH11278902A - Slope spraying material and slope spraying method using the same - Google Patents

Abstract

(57) [Summary] [Problem] To provide a slope spray material which can maintain workability and does not lose strength due to drying. A hardened material containing cement, calcium aluminate and gypsum, and a setting retarder,
A slope spraying material having a pot life of 0 to 180 minutes. Instead of the hardened material, a hardened material slurry containing the hardened material and water may be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for spraying a slope of cement concrete for preventing a landslide or the like on a slope, particularly to a frame which is arranged in a grid pattern on a sloping slope. The present invention relates to a slope spraying material and a slope spraying method.

[0002]

2. Description of the Related Art The term "slope" refers to a slope formed by cutting or embankment around a highway, a dam, and a steep slope. If the slope is left as it is, erosion due to natural weathering, heavy rain, etc., and slope collapse such as landslides will occur, so it is necessary to protect the slope.

Conventionally, a method of spraying cement concrete directly on a slope to prevent collapse of the slope has been the mainstream, but recently, in order to increase the reinforcing effect of the slope, a formwork has been formed on the slope. (Japanese Patent Publication No. 58-5849)
No. 3). As a method of arranging the formwork on the slope, a wire mesh or a plurality of rebars are arranged on the slope in a grid pattern (cross-girder shape) to create a slope mold, and each intersection of the grid-shaped slope mold is formed. After the anchor is driven into the part, a method is used in which cement concrete is sprayed on the slope formwork to make a concrete frame as a reinforced concrete structure to stabilize the slope. Among these, a free frame method is used which can be directly arranged on a slope without shaping and cutting the slope.
This free frame method is deformable (flexible)
A simple wire mesh and reinforcing bars are placed directly on the slope.

[0004] In the cement concrete used here, the ratio of sand to cement is generally the ratio of sand / cement =
It is blended at a ratio of about 4/1 (weight ratio), and exhibits a compressive strength after 28 days of about ²⁰ to 30 N / mm ^{2 in a} laboratory. However, in actual construction, the compressive strength of sprayed cement concrete is 2
There was a problem that the strength development was low at about 0 N / mm ^{2 or} less. This is because the sand / cement ratio is as high as 4/1, the water ratio is greatly increased with the sand / cement ratio, and the slope is exposed to direct sunlight and is easy to dry. This was largely due to the small consolidation effect.

At present, in order to solve such a problem that the strength development is small, a precast concrete block previously manufactured at a factory as a slope mold is placed on the slope, and the sprayed concrete thickness is increased. 30c
m or thicker sloped formwork to be sprayed.

[0006] However, in general, a large spraying machine such as a spraying robot cannot be carried in a place where a foothold such as a slope is bad, and therefore, an operator has a spraying nozzle and removes a rope dropped from above the slope. In many cases, spraying was performed while moving around the waist. It is difficult to move the slope with the rope wrapped around the waist, and when the sprayed thickness is large, the workability is poor and the work time is long. In addition, when a large amount of the spray material is used, there is a problem that the cost of the spray material increases accordingly.

Further, there is a problem that the sand ratio is large and the long-term strength development is small. Therefore, in order to improve the long-term strength development, a spray material and a spray method which cure quickly are required.

Further, a method has been proposed in which the hardened material slurry is pressure-fed and sprayed. However, it takes time to prepare the slurry, and the pressure-feeding hose becomes clogged or the slurry settles to cause trouble. After completion, there was a problem that the remaining slurry had to be disposed.

[0009]

However, recently, in order to maintain the aesthetic appearance of the slope surface, the pot life of cement concrete on the slope mold surface that has protruded from the slope mold after spraying has been reduced. Materials to have are required. However, when the spray material contains a hard material,
Since the curing time is shortened, the pot life is shortened, and there has been a problem that the iron on the sprayed surface cannot be leveled.

[0010] In order to facilitate the spraying work such as ironing, it is conceivable to use a thin and small sloped formwork having a sprayed thickness of 15 cm. In order to use this thin and small sloped formwork, it is necessary to improve the strength such as seismic resistance. In order to improve the strength, the 28-day strength of sprayed cement concrete in actual construction is 30 N / mm ² or more. Is required.

As a result of intensive studies, the present inventor has found that by adding a setting retarder to a sprayed material containing a hardened material and using a slope sprayed material having a specific pot life, the above-mentioned problems can be solved. The present invention has been completed based on the knowledge that can solve the above problem.

[0012]

That is, the present invention comprises a hardened material containing cement, calcium aluminate and gypsum, a setting retarder, and water.
A slope spraying material characterized by having a pot life of 80 minutes, a hardened material containing cement, calcium aluminate and gypsum, a hardened material slurry containing water, and a setting retardation It is a slope spraying material which contains an agent and has a pot life of 20 to 180 minutes. A slope spraying method characterized by using the slope spraying material, wherein a wire mesh and a plurality of reinforcing bars are arranged on the slope to create a slope mold, and the slope mold is formed. A slope spraying method characterized in that a concrete frame is formed by spraying the slope spray material, and immediately before mixing and spraying with cement, an aqueous solution obtained by dissolving a rapid hardening material and a setting retarder. And a rapid hardening material slurry to mix the slope spraying material, wherein the spraying method comprises the steps of:
The slope spraying method is characterized in that a hardened material slurry and cement are mixed at a position 30 m before the surface.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below.

An object of the present invention is to provide a pot that can be used to level the surface of cement concrete sprayed onto a free frame and to quickly and rapidly harden. The working time is maintained by using a retarder in combination. Another object of the present invention is to improve strength reduction due to rapid drying due to solar radiation. For this reason, by giving the concrete rapid hardening, hydration of the cement is accelerated before receiving drying, and the concrete is initialized. This is to increase the strength. Further, a cement concrete excellent in workability and economic efficiency can be obtained by forming a slurry immediately before spraying a hardened material. The cement concrete of the present invention is a generic term for paste, mortar, and concrete.

The cement used in the present invention includes various portland cements of ordinary, early strength and moderate heat, various mixed cements obtained by mixing blast furnace slag or fly ash with these portland cements, and usually commercially available. Various fine particle cements can be used. Of these, the use of ordinary Portland cement is preferred in terms of economy and workability.

The hardened material used in the present invention contains calcium aluminate and gypsum.

The calcium aluminate in the rapid hardening material used in the present invention is a heat treatment such as calcining a mixture of CaO raw material and Al ₂ O ₃ raw material in a kiln or melting in an electric furnace. This is a rapidly hardened component that causes the setting of cement concrete at an early stage. As for calcium aluminate, when CaO is C and Al ₂ O ₃ is A, a calcium aluminate heat-treated product having a mineral composition such as C ₃ A, C ₁₂ A ₇ , CA, and CA ₂ can be mentioned. One type or two or more types may be used.
Moreover, you may use what grind | pulverized these. Among these, amorphous calcium aluminate is preferable from the viewpoint of reaction activity, and amorphous calcium aluminate obtained by rapidly cooling a heat-treated product corresponding to the C ₁₂ A ₇ composition is more preferable. Also, as other components, sodium, potassium,
Also, calcium aluminate in which an alkali metal such as lithium is partially dissolved can be used. Also, calcium aluminosilicate containing SiO ₂ , one CaO of C ₁₂ A ₇
C ₁₁ was replaced with a halide such as CaF ₂ and A ₇ · C
aX ₂ (X is a halogen such as fluorine), C ₄ containing SO ₃
A ₃ · SO ₃ can be used as well. Furthermore, alumina cement can be used as well.

The particle size of calcium aluminate is preferably 3000 cm ² / g or more in terms of Blaine value, and
m ² / g or more is more preferable. If it is less than 3000 cm ² / g, the initial strength development may be reduced.

As the gypsum in the hardened material used in the present invention, either natural or commercially available gypsum can be used, but from the viewpoint of strength development, type II anhydrous gypsum or natural gypsum is preferable, and type II anhydrous gypsum is more preferable. preferable.

The particle size of the gypsum is 3000 cm in Blaine value.
² / g or more, preferably 4000 to 7000 cm ² / g
Is more preferred. If it is less than 3000 cm ² / g, the initial strength development may be reduced.

The amount of gypsum used is preferably 50 to 250 parts by weight, more preferably 75 to 150 parts by weight, based on 100 parts by weight of calcium aluminate. If the amount is less than 50 parts by weight, the long-term strength development may decrease. If the amount exceeds 250 parts by weight, the initial setting properties and the long-term strength expression may deteriorate.

The amount of the rapid hardening material used in the present invention is preferably 5 to 20 parts by weight, more preferably 7 to 15 parts by weight, based on 100 parts by weight of cement. If the amount is less than 5 parts by weight, the initial strength expression may not be improved, and if it exceeds 20 parts by weight, the long-term intensity expression may be reduced.

The setting retarder used in the present invention refers to an agent that retards the setting of cement concrete. The setting retarder is not particularly limited, but any commercially available setting retarder can be used. The setting retarder may be previously mixed with the hardened material, and when preparing the hardened material slurry, it is dissolved in water mixed with the hardened material and used as an aqueous solution (hereinafter referred to as a setting retardant liquid). However, it is preferable to use a setting retarder liquid in that the setting retarder can be used uniformly. Water used for kneading cement, such as tap water or well water, is used as the setting retardant liquid.

Examples of the setting retarder include organic acids, alkali metal carbonates, and phosphates.

Examples of the organic acids include oxycarboxylic acids such as citric acid, tartaric acid, malic acid, and gluconic acid, and sodium and potassium salts thereof, and one or more of these may be used in combination. good. Among these, citric acid and sodium or potassium salts of citric acid are preferred from the viewpoint of developing strength.

Examples of the alkali metal carbonate include carbonates such as lithium carbonate, sodium carbonate and potassium carbonate;
Bicarbonates such as sodium bicarbonate and potassium bicarbonate are exemplified. Among these, sodium carbonate and potassium carbonate are preferable in terms of economy and solubility. The particle size of the alkali metal carbonate is not particularly limited.

Examples of the phosphate include polyphosphate, sodium phosphate monobasic, sodium phosphate dibasic, sodium phosphate tribasic, and sodium tripolyphosphate. Among these, in terms of setting retardation and strength development,
Sodium tripolyphosphate is preferred.

Among these setting retarders, organic acids are preferred from the viewpoint of short-term and long-term strength development.

The setting amount of the setting retarder is preferably from 0.3 to 5 parts by weight, more preferably from 0.5 to 5 parts by weight, based on 100 parts by weight of cement.
3 parts by weight is more preferred. If the amount is less than 0.3 part by weight, sufficient retardation may not be obtained, and if it exceeds 5 parts by weight, the cement concrete may be hardly hardened.

The slope spraying material used in the present invention must have a pot life of 20 to 180 minutes, and 30 to 12 minutes.
Preferably, it is 0 minutes. If the time is less than 20 minutes, no working time is required for leveling the iron after spraying, and if the time exceeds 180 minutes, the cement concrete dries and the long-term strength development is reduced.

In the present invention, in order to reduce the amount of dust,
It is preferable to mix a setting retarder solution obtained by dissolving a setting retarder in water with a rapidly hardened material to form a rapidly hardened material slurry. The obtained rapidly hardened material slurry is used by being mixed with cement concrete.

When the setting retarder solution is used, the concentration of the setting retarder in the setting retarder solution is preferably 5 to 40% by weight, more preferably 8 to 30% by weight. When the amount is less than 5% by weight, the required amount of the setting retarder is used, so that the amount of the setting retarder liquid used increases, so that the concentration of the rapidly hardened material slurry decreases, and the strength development may be reduced.
If the amount exceeds% by weight, the amount of the setting retarder used becomes too large, and the initial curing properties may be reduced.

The amount of water used in the rapidly hardened material slurry is not particularly limited, but is preferably 30 to 400 parts by weight based on 100 parts by weight of the rapidly hardened material. If the amount is less than 30 parts by weight, the viscosity of the hardened material slurry becomes high, and the discharge hole of the shower ring for mixing the hardened material slurry and the cement concrete may be clogged. There is a possibility that the ratio becomes high and the strength development becomes small.

The amount of water used in the rapidly hardened material slurry is preferably different between the wet spraying method and the dry spraying method.
In the wet spraying method, 30 parts per 100 parts by weight of the rapidly hardened material
It is preferably from 100 to 100 parts by weight, more preferably from 40 to 70 parts by weight. In the dry spraying method, 30 to 400 parts by weight is preferable, and 40 to 200 parts by weight is more preferable.

As the aggregate used in the present invention, any of coarse aggregate and fine aggregate can be used, but wire mesh can be used, and
Aggregates having a fine aggregate ratio of 70 to 100% are preferred because they are less likely to rebound when sprayed onto a wire mesh formwork. Further, those having high aggregate strength and high stability are more preferable.

The cement concrete used in the present invention preferably has a unit cement amount of about 300 to 600 kg / m ³ . There is a possibility that the less than 300 kg / m ³ is short or long-term strength development decreases, 600 kg / m ³
Exceeding the viscosity may increase the viscosity of the concrete and make it difficult to spray.

The amount of water used in the present invention is 3 in terms of a binder ratio (W / B) between water and a binder composed of cement and a hardened material.
5 to 80% is preferable, 40 to 60% is more preferable,
40-55% is most preferred. It should be noted that the amount of water mentioned here includes water in the rapidly hardened material slurry. 35%
If the amount is less than 60%, the fluidity of the cement concrete is poor, and there is a possibility that the pumping performance may be impaired. If the amount exceeds 60%, the strength development may be reduced.

The cement concrete of the present invention can use any of paste, mortar and concrete. However, it is difficult to rebound when sprayed on a wire mesh form.
Mortars are preferred.

In the present invention, various admixtures such as a water reducing agent, an AE agent, fibers and fine powder may be used in combination for the purpose of improving the properties of cement concrete.

The water reducing agent can improve the fluidity of cement concrete, and includes naphthalene sulfonate type formalin condensate, melamine sulfonate type formalin condensate, polycarboxylic acid type polymer compound and the like. It is preferred to use. The AE agent can prevent frost damage of cement concrete. The fibers are particularly effective in preventing cracks in the anchor portion. The fine powder fills the voids to form a dense structure, aiming at high strength,
Silica fume or the like can be used.

As a slope spraying method using the slope spraying material used in the present invention, the slope spraying material may be directly sprayed on the slope, but in order to increase the reinforcing effect of the slope, the slope spraying method may be used. It is preferable to arrange a mold on the surface, and a free frame method is more preferable.

The following method is preferable as a method of arranging a wire net used in the free frame method, but is not particularly limited. Two wire meshes (corrugated reinforcing bars φ1 to 3 mm) each having a width of 30 to 60 cm and a length of about 1 to 3 m are arranged in parallel in the longitudinal direction along the slope at intervals substantially equal to the width of the wire mesh. A frame form is formed on the wire nets laid in parallel and in the width direction by using a spacer such as a reinforcing bar for determining the width of the two wire nets. Although this frame form is extended in the vertical direction and the horizontal direction, an intersection part frame may be used at the intersection of the frame form. The slope spraying material is sprayed into the frame form arranged in this manner, and the slope spraying material protruding from the wire mesh of the frame form is leveled to maintain the beauty of the frame.

As the slope spraying method for the slope spraying material used in the present invention, a commonly used dry / wet spraying method can be used. Among them, the wet spraying method is preferable because the amount of generated dust is small.

The method of spraying the rapidly hardened material slurry in the slope spraying material used in the present invention is as follows. The cement concrete pumping pipe is placed at a position before the spray nozzle, preferably 1 to 30 m from the spray nozzle, more preferably 3 to 30 m. It is preferable to attach and spray an additive device, for example, a shower ring, for forcibly mixing the cement concrete and the rapid hardening material slurry at a position 10 to 10 m before. If it is less than 1 m, the mixing of the cement concrete and the rapid hardening material slurry may be insufficient, and if it exceeds 30 m, the cement and the rapid hardening material slurry may react during the pressure feeding in the pressure feeding pipe, and the pressure feeding pipe may be blocked. .

On the other hand, it is preferable that the rapidly hardened material is pressure-fed at a pressure of 0.1 to 0.5 MPa by a rapid hardened material adding machine "NATOM CLEAT". When used as a rapidly hardened material slurry, the set retarder liquid is further added to the slurry by a high pressure water pump for about 2 hours.
Pressurized before showering at a pressure of MPa, mixed with a hardened material immediately before being sent to the showering to prepare a hardened material slurry, forcibly mixed with cement concrete from the showering as a slope spray material , Spray on the slope.

The rapidly hardened material slurry is prepared by pressure mixing of the rapidly hardened material fed by compressed air and a high-pressure setting retarder solution. If the concentration fluctuates, use a static mixer or the like to mix the hardened material and the set retarder liquid,
It is preferable that the prepared hardwood slurry is pressure-fed to a shower ring and mixed with shotcrete. Also, the hardened material and the setting retarder liquid may be mixed in the shower ring.

[0047]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a detailed description will be given based on embodiments.

Example 1 Shotcrete having a unit cement amount of 450 kg / m ³ , W / C = 45% and s / a = 70% was prepared, and this was pneumatically pumped by a concrete pumping machine “Aliver 280”. A shower ring was provided in the middle of air blowing of the sprayed concrete, a static mixer was provided at the entrance of the shower ring, and a Y-tube was provided at the entrance of the static mixer. Calcium aluminate 1 from one side of Y-tube
A rapidly hardened material composed of 00 parts by weight and 100 parts by weight of gypsum was pressure-fed to a shower ring by a rapidly hardened material adding apparatus “NATOM CLEAT” so as to be 10 parts by weight with respect to 100 parts by weight of cement. From the other of the Y-tube, a setting retarder solution obtained by dissolving a setting retarder in an amount shown in Table 1 with respect to 100 parts by weight of cement in 60 parts by weight of water with respect to 100 parts by weight of the rapidly hardened material. It was pumped to the shower ring with a pump. Immediately before being sent to the shower ring, the rapid hardening material and the setting retarder liquid are forcibly mixed by a water pressure at a static mixer to form a rapid hardening material slurry, and the rapid hardening material slurry is discharged from the shower ring at a position 5 m before the spray nozzle. The shotcrete was press-fitted and mixed to form a rapidly hardened shotcrete, which was then sprayed. This rapidly hardened shotcrete was evaluated. Table 1 shows the results. (Materials used) Cement: ordinary Portland cement, commercial product, specific gravity 3.16 Fine aggregate: river sand from Himekawa, Itoigawa city, Niigata prefecture, specific gravity 2.62 Coarse aggregate: billiard gravel from Himekawa, Itoigawa city, Niigata prefecture, specific gravity 2.65 Calcium aluminate: Corresponding to C ₁₂ A ₇ composition, amorphous, Blaine value: 6050 cm ² / g Gypsum: Type II anhydrous gypsum, Blaine value: 6050 cm ² / g Setting retarder: sodium citrate, commercially available product (measurement method Pot life: The pot life after spraying the slope spraying material until the dent disappeared by touching the finger was taken as the pot life. Compressive strength after 28 days: In an environmental test room at 20 ° C. and 80% humidity, a rapidly hardened shotcrete is sprayed on a mold having a width of 50 cm, a length of 50 cm and a thickness of 20 cm, and a diameter of 5 cm × length collected by coring. 200kN for 10cm specimen
The compression strength was determined by measuring with a pressure machine. Compressive strength under sunlight: In the summer, when the temperature is 30 ° C, in the sunny weather, the surface temperature of the surface is 50-60 ° C, and in the direct sunlight, a rapidly hardening shotcrete is sprayed on a formwork of 50cm wide x 50cm long x 20cm thick. 5cm in diameter x 10cm in length
Was measured with a 200 kN pressure machine after 28 days of material age. Workability: Rapid-hardening shotcrete was sprayed on a mold having a width of 10 cm, a length of 40 cm and a thickness of 10 cm, and the surface of the mold was leveled with a trowel and neatly formed. The case where molding was easily performed without applying force to the hand was evaluated as ○, the case where molding was performed with applying force was evaluated as △, and the case where molding was impossible even when force was applied was evaluated as x. Sag: A slope mold having a width of 30 cm and a thickness of 30 cm was crossed and arranged on the slope. After that, spray hardened shotcrete onto the sloped formwork and observe it.The case where dripping and skin dropping were seen a lot was marked with X, the case where it was seen a little was marked with △, and the case where it was not seen at all was marked with ○. .

[0049]

[Table 1]

Example 2 A rapidly hardened material composed of 100 parts by weight of calcium aluminate and the amount of gypsum shown in Table 2 was used in an amount of 10 parts by weight with respect to 100 parts by weight of cement. 6
Performed in the same manner as in Example 1 except that a hardening shotcrete was prepared using a setting retarder solution obtained by dissolving 1 part by weight of a setting retarder in 100 parts by weight of cement in 0 parts by weight of water. Was. This rapidly hardened shotcrete was evaluated. Table 2 shows the results. (Measurement method) Compressive strength after one day: In an environmental test room at 20 ° C. and 80% humidity, a rapidly hardened shotcrete is sprayed on a mold having a width of 50 cm, a length of 50 cm and a thickness of 20 cm, and the diameter is sampled by coring. A 5 cm × 10 cm length specimen was measured with a 200 kN pressure resistance machine to determine the compressive strength.

[0051]

[Table 2]

Example 3 10 parts by weight of the hardened material was used for 100 parts by weight of the cement, and 100 parts by weight of the cement was added to 100 parts by weight of the hardened material in water used as shown in Table 3. The same procedure as in Example 1 was carried out except that a hardening shotcrete was prepared using a setting retarder solution in which 1 part by weight of a setting retarder was dissolved. This rapidly hardened shotcrete was evaluated. Table 3 shows the results. (Measurement method) Dust amount: A slope mold having a width of 30 cm and a thickness of 30 cm was crossed in a cross shape and arranged on the slope. Thereafter, the rapidly hardening shotcrete was sprayed onto the sloped formwork at a pumping speed of 4 m ³ / h for 30 minutes. The dust amount was measured every 10 minutes at a fixed position of 3 m from the spray location, and the average value of the measured values was shown. Pumpability: A rapidly hardened shotcrete was sprayed at a pumping speed of 0.4 m ³ / h and a pumping pressure of 0.40 MPa using a pumping tube for 30 minutes, and the pressure in the pumping tube was measured. The case where the pressure in the pumping pipe is 0.40 to 0.55 MPa is ◎, even if the pressure in the pumping pipe becomes 0.60 MPa or more at which the inside of the pumping pipe tends to be closed, 0.40 to 0.55 MPa is applied by giving an impact to the pumping pipe.
The case where the pressure was 5 MPa was evaluated as ○, and the case where the pumping tube was closed and the pressure did not reach 0.40 to 0.55 MPa even when an impact was applied thereto was evaluated as ×.

[0053]

[Table 3]

Example 4 100 parts by weight of the rapidly hardened material was used in 100 parts by weight of cement, and 100 parts by weight of the cement was used in 100 parts by weight of water. Example 1 was carried out in the same manner as in Example 1 except that a hardening shotcrete was prepared using a setting retarder solution in which 1 part by weight of a setting retarder was dissolved per part. This rapidly hardened shotcrete was evaluated. Table 4 shows the results.

[0055]

[Table 4]

Example 5 10 parts by weight of a hardened material was used for 100 parts by weight of cement, and 60 parts by weight of water was used for 100 parts by weight of a hardened material. Using a setting retarder solution in which 1 part by weight of a setting retarder has been dissolved, mixing the rapidly hardened material slurry with the sprayed concrete at a position before the distance shown in Table 5 from the spray nozzle to obtain a rapidly hardened shotcrete. Other than that, it carried out similarly to Example 1. This rapidly hardened shotcrete was evaluated. Table 5 shows the results. (Measurement method) Mixability: 50 ° C in an environmental test room at 20 ° C and 80% humidity
The appearance of the rapidly hardening sprayed concrete surface sprayed on a mold having a size of 50 cm × length 50 cm × thickness 20 cm was evaluated. × when streaks or spots were found on the entire surface, ○ when streaks or spots were found on a part of the surface, ◎ when there were no streaks or spots on the entire surface and uniform And

[0057]

[Table 5]

[0058]

EFFECTS OF THE INVENTION By using the slope spraying material of the present invention, workability can be maintained, and hydration of cement is promoted at an early stage to increase the strength. A spray material is obtained. Further, since the strength development is large, it can be made thinner than the conventional sprayed thickness. Especially,
When using the hardened material slurry, the amount of dust can be significantly reduced, and immediately before spraying the hardened material slurry, the hardened material slurry and the cement concrete are settled and clogged in the pumping pipe to mix and stir. Work time is reduced,
Since the burden on the worker is reduced, the slope spraying work with good workability can be performed.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C04B 22:14) 103: 14 103: 22 111: 20

Claims (6)

[Claims] 1. A slope comprising a hardened material containing cement, calcium aluminate and gypsum, a setting retarder, and water and having a pot life of 20 to 180 minutes. Spraying material. 2. A hardened material slurry containing cement, calcium aluminate and gypsum, a hardened material slurry containing water, and a setting retarder, and
A slope spraying material having a pot life of 0 minutes. 3. A slope spraying method comprising using the slope spraying material according to claim 1 or 2. 4. A slope frame is formed by arranging a wire mesh or a plurality of reinforcing bars on a slope, and a concrete frame is formed by spraying the slope spraying material according to claim 1 on the slope mold. A slope spraying method characterized by the following. 5. The rapid hardening material slurry according to claim 2, wherein the rapid hardening material and an aqueous solution obtained by dissolving a setting retarder are mixed immediately before mixing and spraying with the cement. Slope spraying method for slope spray material. 6. The slope spraying method according to claim 5, wherein the rapid hardening material slurry and the cement are mixed at a position 1 to 30 m before the spray nozzle.