JPH0414229B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field) The present invention relates to excavated walls in the construction of tunnels for roads, waterways, sewers, pipes, etc., excavated walls in the excavation of mountains, hills, and general ground, and external walls of buildings. Concerning methods for lining walls such as walls.

(Prior Art) As a lining method in which a wall surface such as an excavated wall or an external wall is covered with a lining material containing cement and a lining wall is provided on the wall surface, the cement is generally rapidly set on the lining material. A so-called spraying method is used in which a quick-setting agent and water are mixed and the mixture is sprayed from a spray nozzle toward the wall surface.

This spraying method is described in Japanese Unexamined Patent Publication No. 58-27992.
As described in publications such as JP-A No. 57-209366 and JP-A No. 58-143098, a liquid mixture, that is, a slurry, in which a lining material consisting of cement and aggregate is mixed with water, and the above-mentioned rapid setting. A wet construction method in which an aqueous solution of an agent is combined with a spray nozzle and sprayed, and a powder mixture consisting of the lining material (cement, aggregate) and quick-setting agent is combined with water and sprayed with a spray nozzle. There is a dry method for attaching. As quick-setting agents used in such spraying methods, those whose main components are calcium aluminate, alkali aluminate, alkali carbonate, etc. are widely used.

However, the conventional spraying method uses spring water, running water, etc.
Although it is possible to provide a lining wall on a wall surface free of so-called free water released from the wall surface to be lined, it is difficult to provide a lining wall on a wall surface with a large amount of free water. This is due to the fact that in the conventional spraying method using a conventional quick-setting agent, the curing time of the cement is long, around 1 minute, and the adhesion of the lining material to the wall surface is insufficient.

For this reason, in the conventional spraying method that uses a conventional quick-setting agent, in order to install a lining wall on a wall surface with a large amount of free water, it must be carried out after temporarily blocking the free water. However, the work is complicated. In addition, even if the above treatment is applied, the adhesion to wet walls is insufficient, so with conventional construction methods, the lining material and quick-setting agent tend to peel off from the wall surface, resulting in poor material yield. .

It is known that acrylates or methacrylates are useful in reducing the setting time of cement slurries, ie, as cement quick setting agents. However, there are no examples of these agents being actually used as quick-setting agents for spraying construction methods for lining materials containing cement, and there is no evidence that they can be suitable quick-setting agents for specific methods of use. It was completely unknown.

(Objective of the Invention) The present invention forms a stable lining wall on both dry wall surfaces and walls where a large amount of free water exists, without pre-treating these wall surfaces for free water. The purpose is to provide a lining method that can.

(Structure of the Invention) The present invention involves spraying a lining material containing cement, a rapid setting agent selected from acrylates and methacrylates, and an oxidizing agent as a catalyst toward a wall surface from a spray nozzle. A lining method for coating the wall surface by adding the oxidizing agent to at least one of the lining material and the quick-setting agent, and applying the lining material and the quick-setting agent to the spray nozzle through separate routes. The lining material, quick-setting agent, and oxidizing agent are simultaneously sprayed from the spray nozzle toward the wall surface.

The present invention also provides the above method by spraying a lining material containing cement, a rapid setting agent selected from acrylates and methacrylates, an oxidizing agent, and a reducing agent toward a wall surface from a spray nozzle. A lining method for coating a wall surface, wherein one of the oxidizing agent and the reducing agent is added to the lining material, and the other is added to the quick-setting agent, and the lining material and the quick-setting agent are passed through separate routes. The lining material, quick-setting agent, oxidizing agent, and reducing agent are supplied to a spray nozzle and are simultaneously sprayed from the spray nozzle toward the wall surface.

The present invention further provides a lining material containing cement;
A lining method for coating a wall surface by spraying a rapid setting agent selected from acrylates and methacrylates, an oxidizing agent, and a reducing agent toward the wall surface from a spray nozzle, the oxidizing agent and a reducing agent are respectively added to the lining material or the quick-setting agent, the lining material and the quick-setting agent are supplied to the spray nozzle via separate routes, and the lining material, the quick-setting agent, The method is characterized in that an oxidizing agent and a reducing agent are simultaneously sprayed from the spray nozzle toward the wall surface.

(Effects of the Invention) According to the present invention, since the quick-setting agent selected from acrylates and methacrylates is used, the hardening time of cement is short, the adhesive strength of the lining material to the wall surface is strong, and furthermore, after hardening, The strength of the lining walls is high. Therefore, a strong and stable lining wall can be provided on a wall surface with abundant free water such as spring water or running water without any treatment for the free water, improving work efficiency. Becomes cheaper. Further, since the quick-setting agent and the lining material are separately supplied to the spray nozzle, and the two are combined at the spray nozzle, the spraying work is easy.

When a wall with a large amount of free water is lined by the method of the present invention, acrylate or methacrylate is polymerized by an oxidizing agent to form polyacrylate or polymethacrylate, and at the same time hardens the cement.
Furthermore, even though a large amount of free water exists on the wall surface, it adheres to the wall surface and forms a lining wall to prevent the free water from spouting out.

(Example) Cement Examples of cement include Portland cement, alumina cement, blast furnace cement, white cement,
Although various types of cement can be used, common Portland cement is preferred because of its ease of availability.

Lining materials Lining materials containing cement are
It often contains aggregates such as sand and gravel. In the present invention, the lining material containing cement, with or without aggregate, can be used in the form of either a liquid mixture mixed with water, that is, a slurry, or a powder mixture. However, lining materials, especially cement, are
Preferably, it is used in the form of a powdered mixture.

Accelerating Agents Accelerating agents are either acrylates or methacrylates that polymerize to form polyacrylates or polymethacrylates upon incorporation of an oxidizing agent. Salts in these drugs include alkali metal salts, alkaline earth metal salts, aluminum salts, etc., and magnesium salts are preferred in the present invention.

Preferably, the acrylate or methacrylate is used in the form of an aqueous solution. In addition, the concentration of acrylate or methacrylate in the composition for lining walls is preferably 10 to 50% by weight in the solution excluding insoluble substances such as cement and aggregate;
In particular, a content of 15 to 45% by weight is more suitable.

If the concentration of acrylate or methacrylate in the solution is less than 10%, the adhesion to the wall surface will be insufficient and the initial strength after curing will be weak, so that the resulting lining wall will not function properly. does not have If the concentration exceeds 50%, the viscosity increases and acrylate or methacrylate crystals precipitate, making it difficult to use, which is not preferable.

Oxidizing agent The oxidizing agent is a polymerization catalyst for the ion exchange reaction of the acrylate or methacrylate,
Hydrogen peroxide or a water-soluble compound that produces hydrogen peroxide. Compounds that generate hydrogen peroxide include peroxide salts such as sodium percarbonate, sodium perforate, sodium peroxide, calcium peroxide, barium peroxide, and ammonium peroxide, and peroxide salts such as potassium persulfate and sodium persulfate. Sulfates, etc. However, since ammonium persulfate produces ammonia as a by-product, it is preferable to avoid using it in a poorly ventilated place.

The oxidizing agent may be added to the aqueous solution of acrylate or methacrylate, or may be added to the lining material containing cement.

Combination of oxidizing agent and reducing agent It is possible to polymerize acrylate or methacrylate by using oxidizing agent alone, but if you want to shorten the curing time, or if the curing time is longer due to the temperature of the work site, etc. It is desirable to use it together with a reducing agent.

When using an oxidizing agent and a reducing agent together, it is preferable to add the oxidizing agent to an aqueous solution of acrylate or methacrylate and add the reducing agent to the lining material containing cement, but vice versa. Alternatively, both the oxidizing agent and the reducing agent may be added to only one of the lining material or the quick-setting agent. When adding an oxidizing agent or a reducing agent to the lining material, it is preferable to mix them with the lining material, and especially when using the lining material in powder form, thoroughly knead both together. It is preferable to keep it.

Reducing agent The reducing agent used in combination with the oxidizing agent is preferably water-soluble, and includes amines such as diethanolamine, triethanolamine, hydrazine, hydroxylamine, diethylaminopropionitrile, dimethylaminoethanol, dimethylaminopropanol, piperazine, and morpholine. Yaso salt, 1st
Iron salts, alkali sulfites, thiosulfates, thiourea,
Sodium erythorbate, Rongarit, etc. 1
Use more than one species. The combination of oxidizing agent and reducing agent and the amount used will affect the curing time of the lining wall, the adhesive strength of the lining wall to the wall surface, the strength of the lining wall, etc., so the geology, environment, and temperature of the work site will be affected. Select based on the following conditions.

Mixing ratio The preferred mixing ratio of cement and quick-setting agent differs depending on whether cement is used in powder form (dry method) or slurry (moist method).

It is particularly preferable to use cement in powder form because in the present invention, the cement and quick-setting agent are combined using a spray nozzle. When the cement is used in powder form, the flowability of the cement and accelerator mixture is not a problem. Therefore, the ratio of the quick setting agent solution to the cement powder may be small, and is 0.05 to 7, preferably 0.1 to 5 in volume ratio. If the volume ratio is less than 0.05, the surface of the cement or aggregate cannot be wetted, so a strong lining wall cannot be obtained, and the resulting lining wall has many voids and has poor water-stopping properties. ,
Furthermore, there is a possibility that the adhesion to the bedrock and ground may become weaker. If the volume ratio exceeds 7, there will be no problems with water-stopping or adhesive properties, but the polymerized quick-setting agent (polymethacrylate or polymethacrylate) will have a marked tendency to gel, resulting in poor elasticity. Although it is possible to obtain a lining wall with rich properties, there is a possibility that a strong lining wall cannot be obtained.

When using cement in slurry form,
Water is added to a mixture of cement, aggregate, and reducing agent if necessary to make a fluid slurry.
The slurry and an aqueous solution of an accelerating agent (acrylate or methacrylate) are combined using a spray nozzle. Therefore, when cement is used in the form of a slurry, the lower limit of the ratio of liquid to solid is larger than in the dry method, and the ratio of liquid to solid is 1 to 7, preferably 1 by volume. ~5. If the volume ratio is less than 1, the slurry and the aqueous solution of the quick setting agent will be insufficiently mixed, making it impossible to obtain a homogeneous lining wall. If the volume ratio exceeds 7, a strong lining wall cannot be obtained.

The curing time for the wall lining is as follows for the spraying method:
Generally, it is desired that the time be 30 seconds or less, preferably 10 seconds or less, so it can be freely set to about 1 second by adjusting the types of oxidizing agent and reducing agent and their amounts (concentrations). I can do it. The curing time also depends on the temperature at the work site.

Construction Method In the present invention, the lining material and the quick-setting agent are separately supplied to a spray nozzle, and the two are combined at the spray nozzle.

When using cement in powder form, add an oxidizing agent to one of the cement-containing lining material and the aqueous solution of the quick-setting agent, thoroughly dry mix the lining material,
The lining material and the aqueous solution of the quick-setting agent are combined with a spray nozzle and simultaneously sprayed toward the wall surface. In this case, it is preferable to supply water to the spray nozzle and let it merge. When using a reducing agent together, it is sufficient to add an oxidizing agent to one of the lining material or quick-setting agent, and a reducing agent to the other. .

When using cement in slurry form,
Water may be added to the lining material containing cement, thoroughly kneaded, the kneaded lining material and the aqueous solution of the quick-setting agent may be combined using a spray nozzle, and the mixture may be sprayed simultaneously toward the wall surface. In this case as well, the oxidizing agent is included in either the lining material or the aqueous solution of the quick-setting agent.

As an apparatus for carrying out the present invention,
NATM (New Austrian Tunneling Method)
It is possible to use a dry or wet spraying machine used in the tunnel construction method known as .

Depending on the condition of the wall to be lined, auxiliary work such as installing lock bolts, reinforcing reinforcing bars or wire mesh may be performed.

The thickness of the spraying, that is, the thickness of the lining wall, varies depending on the purpose of the construction. When the thickness exceeds 2 to 3 cm, it is preferable to perform so-called multiple spraying, in which the coating is sprayed in multiple doses.

Construction example 1 10L (12Kg) of an aqueous solution containing 34% magnesium acrylate and 3% sodium persulfate are combined with a cement slurry made by kneading 17Kg of Portland cement and 0.02Kg of sodium erythorbate with 8L of water using a spray nozzle. Then, spray it on a wall with running water to obtain a wall lining. At this time, the curing time of the sprayed composition was approximately 1.2 seconds (24 degrees Celsius), and the compressive strength of the cured product was 15 kg after 1 hour of curing.
f/cm ² , and the composition cured on the mortar wall firmly adhered to the mortar wall and did not peel off easily.

The volume ratio of the solution portion to the solid portion of the sprayed composition was 3.3. However, the specific gravity of cement is 3.1.

Construction example 2 Aqueous solution containing 25% magnesium acrylate, 9% calcium acrylate, and 3% sodium persulfate
10L (12Kg), 17Kg of Portland cement, 17Kg of river sand and 0.02Kg of sodium erythorbate.
A cement slurry mixed with 11 L of water was mixed with a spray nozzle and sprayed onto a wall with running water to obtain a lining wall. At this time, the curing time of the sprayed composition was about 1.3 seconds (25 degrees C), and the compressive strength of the cured product was 10 Kgf/cm ² after 1 hour of curing.
The composition cured on the mortar wall firmly adhered to the mortar wall and did not peel off easily.

The volume ratio of the solution portion to the solid portion of the sprayed composition was 1.8. However, the specific gravity of sand is 2.6.

Construction example 3 33L (40Kg) of an aqueous solution containing 25% magnesium acrylate and 3% sodium persulfate, 67Kg of Portland cement, 67Kg of river sand, and crushed stone of 1 to 5 mm.
A mixture of 130 kg and 0.07 kg of sodium erythorbate was mixed together using a spray nozzle and sprayed onto an excavated rock surface with running water to obtain a lining wall. At this time, the curing time of the sprayed composition was less than 1 second (20 degrees Celsius), and the compressive strength of the cured product was
The composition was 72 Kgf/cm ² after 1 hour of curing, and the composition hardened on the rock firmly adhered to the rock and did not peel off easily.

The volume ratio of the solution portion to the solid portion of the sprayed composition was 0.3.

Construction example 4 34L (40Kg) of an aqueous solution containing 20% magnesium acrylate and 3% ammonium persulfate, 100Kg of Portland cement, and 22kg of fly ash.
Kg and a mixture obtained by dry kneading were combined with a spray nozzle and sprayed onto the wet excavated rock surface to obtain a lining wall. At this time, the curing time of the sprayed composition was 13 seconds or less (24 degrees Celsius), and the compressive strength of the cured product was
It was 64 Kgf/cm ² after 1 hour of curing, and the composition hardened on the rock solidly adhered to the rock and did not peel off easily.

The volume ratio of the solution portion to the solid portion of the sprayed composition was 0.8. However, the specific gravity of the fly ash is 2.6.

Comparative example 1 10 kg of cement, 30 kg of river sand, commercially available powdered quick setting agent
0.5Kg was mixed dry, mixed with 7.1Kg of water using a spray nozzle, and sprayed onto a mortar wall with running water.

The sprayed composition has a curing onset time of 1.5~
For 2 minutes, it was washed away by the running water and a lining wall could not be obtained.

Embodiment of lining device The lining device 10 shown in FIG.
including. Lining material 12 consists of cement, aggregate, and reducing agent, is mixed by mixer 12, and is transferred to sprayer 20 by belt conveyor 18.

Compressed air is sent from a compressor 22 to the spray machine 20 via a pipe 24, and the lining material 12 transferred to the spray machine 20 is sent to the spray nozzle 16 via a pipe 26 by the spray machine 20. .

The spray nozzle 16 is filled with water 30 in a tank 28.
is sent through the pipe 34 by the booster pump 32, and the quick setting agent 38 in the tank 36 and the oxidizing agent 42 in the tank 40 are sent to the booster pump 44.
Compressed air is sent from the compressor 22 through a pipe 46 and compressed air is sent from the compressor 22 through a pipe 48.

For this reason, the lining material 12, water 28, quick-setting agent 38, and oxidizing agent 42 are combined at the spray nozzle 16, and then flowed from the spray nozzle 16 to the wall surface to be lined.
0 at the same time, this causes the wall surface 5
A lining wall 52 is formed at 0.

[Brief explanation of drawings]

The accompanying drawings are diagrams schematically showing a suitable lining device for use in carrying out the present invention. 10: Lining device, 12: Lining material, 14: Mixer, 16: Spray nozzle, 20: Spray machine, 2
2: compressor, 30: water, 38: quick setting agent,
42: Oxidizing agent, 50: Wall surface to be lined, 52: Wall to be lined.

Claims (1)

[Claims] 1. By spraying a lining material containing cement, a rapid setting agent selected from acrylates and methacrylates, and an oxidizing agent as a catalyst from a spray nozzle toward the wall surface, A lining method for covering a wall surface, wherein the oxidizing agent is added to at least one of the lining material or the quick-setting agent, and the lining material and the quick-setting agent are supplied to the spray nozzle through separate routes. ,
A method for lining a wall surface, comprising simultaneously spraying the lining material, quick-setting agent, and oxidizing agent toward the wall surface from the spray nozzle. 2. The lining method according to claim 1, wherein the lining material is a powder mixture, and the mixture, the quick-setting agent, and water are combined and sprayed using the spray nozzle. 3. The lining method according to claim 1, wherein the lining material is a liquid mixture, and the liquid mixture and the quick-setting agent are combined and sprayed by the spray nozzle. 4. The lining method according to claim 1, 2, or 3, wherein the quick setting agent is an aqueous solution. 5. The lining according to claim 1, 2, or 3, wherein the aqueous solution of the quick setting agent and the aqueous solution of the oxidizing agent are mixed, and the mixed aqueous solution is supplied to the spray nozzle. Method. 6. The lining method according to claim 5, wherein the mixed aqueous solution is supplied to the spray nozzle together with compressed air. 7. The lining method according to claim 1, 2, or 3, wherein the oxidizing agent is mixed into the lining material. 8 A coating that covers the wall surface by spraying a lining material containing cement, a quick-setting agent selected from acrylates and methacrylates, an oxidizing agent, and a reducing agent toward the wall surface from a spray nozzle. In the method, one of the oxidizing agent and the reducing agent is added to the lining material and the other to the quick-setting agent, and the lining material and the quick-setting agent are supplied to the spray nozzle through separate routes. and a method for lining a wall surface, comprising simultaneously spraying the lining material, quick-setting agent, oxidizing agent, and reducing agent toward the wall surface from the spray nozzle. 9. The lining material is a powder mixture, and the aqueous solution of the quick-setting agent and the aqueous oxidizing agent are mixed, and the mixed aqueous solution, the mixture, and water are combined and sprayed using the spray nozzle. The lining method according to claim 8. 10 The lining material is a liquid mixture, and the aqueous solution of the quick setting agent and the aqueous solution of the oxidizing agent are mixed,
The lining method according to claim 8, wherein the mixed aqueous solution and the slurry are combined and sprayed by the spray nozzle. 11 A coating material that covers a wall surface by spraying a lining material containing cement, a rapid setting agent selected from acrylates and methacrylates, an oxidizing agent, and a reducing agent toward the wall surface from a spray nozzle. The oxidizing agent and the reducing agent are respectively added to the lining material or the quick-setting agent, and the lining material and the quick-setting agent are supplied to the spray nozzle through separate routes, A method for lining a wall surface, comprising simultaneously spraying the lining material, quick-setting agent, oxidizing agent, and reducing agent toward the wall surface from the spray nozzle.