JPH0573850B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for injecting a drug used as an injection method in the civil engineering and construction fields. [Prior Art] Conventionally, in the civil engineering field, various soil stabilizers and improvers have been used for the purpose of stabilizing the ground and stopping water.
In addition, in the construction field, various chemicals are used by injection method for the purpose of repairing structures mainly made of hydraulic substances. As a method of injecting these drugs into the target area,
There are three methods: (1) natural infiltration method, (2) method using the contraction force of an elastic body, (3) decompression method, (4) method of pressurizing with compressed gas, and (5) method of pressurizing with a pump. The press-in method using is the mainstream. [Problems to be Solved by the Present Invention] Methods (1) and (2) have low working efficiency when injecting highly viscous drugs, and are not suitable for deep injection. Method (3) requires a suction device and is not suitable for deep injection. In general, the penetration status of a drug is determined by the conditions on the injection target side.
For example, the compactness of the construction body made of hydraulic material,
It is affected by various conditions such as the width and length of cracks, soil particle size in the ground, packing density, and the amount of spring water or underground water in tunnels, dams, underground structures, etc. In reality, these conditions vary widely and the permeability of the drug varies greatly depending on the injection location, making it difficult to select injection equipment with appropriate specifications. Furthermore, when injecting an epoxy resin or the like as a chemical into cracks in a concrete structure, for example, the chemical has a high viscosity, so it does not penetrate easily under low pressure and usually takes a long time. If the injection pressure is increased in order to inject this in a short period of time, problems may occur such as enlarging cracks in the structure or injecting the drug into areas other than the intended areas. The basic principle of drug injection is that it should be performed at low pressure, over as wide a range as possible, in a short time, and without loss of the drug. Therefore, it is desirable to use a drug injection device that has performance appropriate to the conditions of the injection site. In general, conditions such as the required pressure and injection speed for drug injection differ depending on the position of the injection hole, so in method (4) or (5), drugs are pressurized into multiple injection points using one pressurizing source. That is difficult. When simultaneously performing work on areas with poor chemical permeability and requiring a long time to inject a small amount of the chemical, and areas with good chemical permeability that allows a large amount of the chemical to be injected in a short period of time, it is important to In the method using a pressure source, a large amount of the chemical is injected into areas where it is easy to penetrate, and no chemical may be detected at areas where it is difficult to penetrate, making the construction work uncertain. In order to accommodate all injection points with different conditions, there is a problem in that a large number of pressurizing sources with different performances must be prepared, or one with a large excess of performance must be used. It costs a lot of money to conduct a boring survey to understand the injection conditions before injecting chemicals, and even if the survey is conducted, the injection conditions often differ depending on the injection position, and in the end, the injection equipment The reality is that we have to prepare everything from small to large capabilities. In addition, when using the press-in method using a pump, if the injection pump is stopped after a certain amount of drug has been injected, the turbulent pressure will disappear, so after that point, the penetration range of the drug cannot be expected to expand significantly, and the penetration range will be deeper and wider. The problem is that in order to push the drug further, it is necessary to supply new drugs, which increases the amount of drugs consumed. [Means for Solving the Problems] As a result of various studies aimed at improving these conventional problems, the present inventors found that when injecting a drug into the target area, solid carbon dioxide in a closed container is vaporized. By using pressure, and by using this pressure at the time of injecting a predetermined amount of drug,
It is possible to further expand the permeation range of chemicals without replenishing new chemicals, and for chemicals that react with carbon dioxide gas, such as silicate-based or cement-based soil stabilizers, The present invention was completed based on the discovery that it is possible not only to expand the permeation range of a drug, but also to shorten the hardening time of the drug and increase gel strength. That is, the present invention is characterized by ``vaporizing solid carbonic acid in an airtight container, and using the resulting pressure to pressurize a drug in an airtight container having a drug outlet to push the drug out of the container. The gist is ``methods of drug injection.'' When solid carbonic acid is filled into a sealed pressure-resistant container, the pressure inside the container gradually increases as the solid carbonic acid vaporizes due to the surrounding heat.However, the present invention is designed to inject drugs and expand the permeation range of drugs. This pressure is used. In the method of the present invention, after injecting a predetermined amount of a drug, the gas is injected by switching to carbon dioxide gas obtained by vaporizing solid carbon dioxide, thereby injecting the drug without having to replenish the drug. It is possible to push the injected drug deeper into the body without diluting it, further expanding the penetration range of the drug. In the method of the present invention, the drug injection pressure can be arbitrarily adjusted by ensuring the pressure resistance of the container and adjusting the amount of solid carbon dioxide charged in accordance with the permeability of the drug to the injection site. If the permeability of the drug is high, a small amount of solid carbonic acid may be used; if the permeability is low, the injection pressure may be increased by increasing the amount of solid carbonic acid. In addition, multiple containers can be combined and used alternately, allowing continuous,
Moreover, it is also possible to inject a large amount of medicine. For example, in the civil engineering field, the method of the present invention can be applied to various soil stabilizers, improvers, water-stopping agents, etc., such as cement-based, silicate-based, bentonite-based, and polymer-based, for the purpose of stabilizing the ground and stopping water. In addition, in the construction field, repair of structures mainly made of hydraulic materials, such as buildings, roads, bridges, tunnels, dams, water and sewage pipes, underground cable pipes, utility ditches, subway facilities, etc., and underground structures and concrete secondary Various chemicals for filling cracks in products, reinforcing them, stopping water, etc.
Examples include polymers for cement admixtures, monomers or polymers for concrete impregnation, liquid resins for resin concrete, rubber latexes used in organic and inorganic adhesives, waterproofing agents, sealants, resin emulsions, mixed dispersions, etc. It can be used to inject water-soluble polymers or monomers such as spargeon, polyvinyl alcohol, polyacrylates, and cellulose derivatives, and liquid polymers such as epoxy resins, unsaturated polyester resins, and urethane resins. We also provide industrial waste treatment, sludge solidification treatment,
It can also be used to inject chemicals used in pollution prevention measures such as solidification treatment to prevent the elution of hazardous substances, especially heavy metals. For injection, these drugs can be used alone or in combination of two or more. River sand, mountain sand, sea sand, silica sand, various lightweight aggregates, calcium carbonate, fly ash, finely divided silica, pozzolan, etc. may be added to these chemicals. The method of the present invention can be applied to materials that can be press-fitted, such as an aqueous solution, a slurry, or a relatively soft paste. The drug may be appropriately selected depending on the purpose of use. For example, when the purpose is to strengthen or stop water from cracks in concrete structures, deteriorated or weakened parts, or places where water is flowing out from cracks in underground structures, epoxy resins, unsaturated polyester resins, etc. Liquid polymers such as resins, urethane resins, water-based polymer dispersions, and various adhesives are used, and when the purpose is to stabilize the ground, soil, and bedrock, cement-based and silicate-based soil materials are used. A stabilizer may be used. In the method of the present invention, the drug and solid carbonic acid may be placed in the same container, or they may be placed in separate containers, and the pressure inlet of each container may be connected to the solid carbonic acid side using an appropriate joint. It is also possible to adopt a method of pressurizing the drug side. The method of the present invention will be explained with the help of figures. FIG. 1 is a schematic diagram showing an example in which a drug and solid carbonic acid are placed in the same container in one embodiment of the method of the present invention. Moreover, FIG. 2 is a schematic diagram showing an example in which a drug and solid carbonic acid are each placed in separate containers in another embodiment of the method of the present invention. An injection hole 1 is provided at the location where the drug is to be injected by drilling a hole as necessary, and an injection tube 2 is inserted. If necessary, filler or caulking material 3 is filled around the injection tube 2 to fix the surface of the injection site and prevent the drug from flowing out from the surface through the gap around the injection tube 2. A drug 5 for injection is charged into a container 4 through a charging port 6, and solid carbonic acid 8 is charged through a charging port 9, and each port other than the drug outlet 7 is sealed. In the case of the system shown in FIG. 2, the pressure inlet ports 10 of the containers 4-a and 4-b are connected by a joint 11-a so that the drug side can be pressurized from the solid carbonic acid side. When the solid carbonic acid is vaporized and the internal pressure of the container 4 (4-a, 4-b in FIG. 2) increases, the drug 5 is pushed out from the outlet 7 and passes through the joint 11-b and the injection pipe 2 to the injection point. is press-fitted into the At least one of a pressure regulator, a safety valve, a blow valve, etc. is attached to the nozzle 12 to regulate the pressure inside each container (not shown). The container used in the present invention is made of an airtight material and is a container for vaporizing solid carbonic acid (hereinafter referred to as
A pressurized container (hereinafter referred to as a pressurized container) has a solid carbon dioxide charging port and a pressure guiding port, and a container containing a drug (hereinafter referred to as a "drug container") has a chemical charging port, a pressure guiding port, and a drug outlet. The structure shall be such that it can be sealed with a lid, valve, etc. as necessary. In the method of the present invention, one container is provided with a solid carbonic acid inlet, a drug inlet, and a drug outlet (one port can also be used in common) to function as both a pressurized container and a drug container. An integrated container can also be used. The container used in the present invention preferably has a structure to which at least one of a pressure regulator, a safety valve, a blow valve, etc. can be attached. When the chemical reacts with carbon dioxide gas, such as with silicate-based or cement-based earth stabilizers, it is possible to obtain favorable results such as shortening the curing time and increasing the strength of the solid body. Pressure can be applied directly to the drug so that it can be absorbed and used effectively. If you want to avoid contact between the drug and carbon dioxide gas, or if you do not want carbon dioxide gas to enter the injection site, use an airtight material made of rubber, synthetic resin, etc.
And, using a container equipped with a flexible membrane,
By separating the medicine and carbon dioxide gas with the internal membrane, it is possible to prevent contact between the medicine and carbon dioxide gas, and also to prevent carbon dioxide gas from entering the injection site. Note that the size of the inner membrane is made to be large enough to accommodate the increase in the gas phase inside the container. It is also possible to use a sliding type where the partition structure is moved using gas pressure, or a piston type. The pressure resistance of the container used in the present invention is such that it can accommodate the required drug injection pressure. Generally, it is preferable for the injection pressure to be as low as possible; however, if it is too low, injection may not be possible or will take a long time, reducing efficiency. For example, in the case of various chemicals for the purpose of repairing concrete structures, the amount usually ranges from 0.1 to 20Kg/cm ² −
G level, and in the case of various soil stabilizers for the purpose of stabilizing the ground and stopping water, it is usually 1 to 50 kg/cm ²
Injection is performed at around -G, and any material that can accommodate this may be sufficient. In the case of the present invention, it depends at most on the physicochemical properties of carbon dioxide. The size of the container used in the present invention can be selected depending on the purpose and is not particularly limited. For example, when injecting into cracks in a concrete structure, the pore volume is small at each location and the amount of drug to be injected is small, so the container should have a volume of 0.01 to 10, preferably 0.05 to 5. The one is good. In addition, when several hundred to several thousand chemicals are injected per injection hole, such as for soil stabilization, the size of the container is preferably about 10 to 100. The material of the container used in the present invention may be selected from a material that can provide the required pressure resistance. For example, rubber or synthetic resin may be used for low pressure applications, and metal may be used for high pressure applications. Note that it is preferable to use a material that has corrosion resistance and is resistant to corrosion caused by chemicals. Accessories for the container used in the present invention include:
A device for supplying chemical solution or solid carbonic acid to a container, a device for adjusting the temperature of the drug, a heating device that can adjust the temperature to adjust the vaporization rate of solid carbonic acid, a pressure regulating device to adjust the pressure inside the container, and a device for maintaining the container. Examples include safety valves, blow valves, thermometers, flow meters, etc. As the solid carbonic acid used in the present invention, commercially available solid carbonic acid can be used, and the solid carbonic acid can be in any shape as long as it can fit into a container. While various liquefied gases need to be handled in pressure-resistant containers, solid carbonic acid can be easily handled at normal pressure, so the method of the present invention is easy to implement at construction sites. This has a great advantage. The rate of vaporization of solid carbonic acid is affected by the ambient temperature and the degree of heat supplementation relative to the amount charged, and the pressure within the container increases slowly. In the case of soil stabilizer injection, at the beginning of the injection,
Because the area around the injection pipe is disturbed by boring water, the drug easily penetrates even at low pressure, but as the infiltrated drug hardens, the resistance increases.
As the viscosity of the injected drug increases over time, it is necessary to increase the injection pressure. In the case of the present invention, the pressure inside the container is low at the start of injection, and as time passes, the pressure inside the container increases as the amount of vaporized solid carbonic acid increases, which is extremely preferable. If you want to obtain high pressure from the beginning of injection, use a small capacity container, or increase the amount of chemical charged to reduce the volume of the gas phase, or increase the amount of solid carbonate charged. Alternatively, if necessary, the pressure can be increased within a short time by heating the solid carbonic acid. The amount of solid carbonic acid used is adjusted depending on the amount of drug to be injected and the injection pressure. For example, when the volume of the gas phase inside the container is 1, the amount of solid carbonic acid required to raise the pressure inside the container to 2 kg/cm ² -G at a temperature of 15° C. is about 0.086 mol. After injecting a predetermined amount of drug into a certain injection point, in order to further expand the permeation range of the drug within the injection point, the residual pressure in the container or the gas pressure obtained by replenishing solid carbon dioxide as necessary is used to fill the area. Pressurize the injection point,
It is best to push the injected medicine inside further. [Effects of the Invention] The effects of the present invention are as follows. (1) The method of the present invention is particularly suitable for injecting a drug simultaneously into a plurality of injection locations having different drug permeability. By attaching the injection device used in the method of the present invention to each injection site, fine-grained construction can be performed depending on the permeability of the drug. (2) By appropriately replenishing and adjusting the amount of solid carbon dioxide in the container, no complicated operations are required, and the solid carbon dioxide itself can be handled under normal pressure, making it simple and labor-saving, making it easy to use at construction sites. Easy to implement. (3) Since it does not require a power source, it has a large energy saving effect, especially in cases where injection takes a long time. (4) By pressurizing the injected drug with carbon dioxide gas, there is no need to replenish new drugs.
The injected drug can be pushed deeper,
The permeation range of the drug can be further expanded. (5) For agents that react with carbon dioxide gas, such as silicate-based or cement-based soil stabilizers, it is important to not only expand the permeation range of the agent, but also shorten the hardening time and improve gel strength. You can get an increasing effect. [Example] Next, the present invention will be explained with reference to an example. Example 1 A hole was drilled into a crack in a reinforced concrete structure, and an injection pipe with a diameter of 10 mm was inserted. The area around the injection pipe and the surface of the concrete were hardened with epoxy resin adhesive. Next, a water pressure of 10 kg/cm ² -G was applied to each injection point for 3 hours, and the amount of water permeation was measured. The results are shown in Table-1. After drying the specimen, a drug was injected using the injection device shown in FIG. 1 according to the following procedure. 900 c.c. of each of the various drugs shown in Table 1 was placed in a metal pressure-resistant container with a volume of 1, and the drug outlet of each container was connected to each injection pipe using a joint. Next, 20 g of each solid carbonic acid was placed in a polyethylene bag having a volume of 1 to prevent direct contact between the drug and the solid carbonic acid, and the bags were inserted and fixed in the pressure-resistant container. As the solid carbonic acid vaporized, the polyethylene bag expanded, thereby compressing the gas phase in contact with the drug, and as the pressure inside the container rose, the drug was injected into the specimen. Injection pressure is 15Kg/cm ² -G
The internal pressure of the container was adjusted using a pressure regulator so that it did not exceed . The injection time was 1 hour for each injection site. The amount of drug injected into each injection site was as shown in Table 1. After the injection treatment was completed, the water permeation amount was measured under the same conditions as before the treatment after being left for one week. As a result, the amount of water permeation was able to be significantly reduced as shown in Table 1.

[Table] Example 2 Ten iron molds were filled with river sand and consolidated. On the other hand, 20% of ethylene carbonate was added as a hardening agent to a mixed solution of 200 parts of JIS No. 3 water glass and 240 parts of water.
An injectable drug with a curing time of 3 minutes was prepared by adding 50% of the total amount. As shown in Figure 2, an injection device assembled by connecting the pressure ports of two polyethylene containers (capacity: 1) is used, and the above drug 1 is added to the first container (drug container). 0.35 mol of solid carbonic acid was charged into each second container (pressurized container), and 400 c.c. of the drug was injected while adjusting the pressure inside the container with a blow valve so as not to exceed 0.5 Kg/cm ² -G. The compressive strength of the compacted soil after being left for one day was 11 Kg/cm ² . After injecting 400 c.c. of the drug in the same manner, the drug container was removed, and the pressurized container was replenished with 0.086 mol of solid carbonic acid, which was vaporized and vented into the mold through the injection tube. The compressive strength of the compacted soil increased to 15 kg/cm ² after being left for one day.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an injection device used in Example 1, in which a drug and solid carbonic acid are placed in the same container in an embodiment of the method of the present invention. FIG. 2 is a schematic diagram showing an injection device used in Example 2, in which a drug and solid carbonic acid are placed in separate containers in another embodiment of the method of the present invention. Explanation of symbols; 1...Injection hole, 2...Injection pipe, 3
...filler or caulking material, 4,4-a,4
-b...Container, 5...Drug, 6...Drug loading port,
7...Medical outlet, 8...Solid carbonic acid, 9...Solid carbonic acid inlet, 9-A...Solid carbonic acid receiver, 9-B...
Inner membrane for partition, 10... Outlet, 11-a, b...
...Joint, 12...Nozzle for mounting pressure regulator, safety valve, blow valve, etc., 13...Mold, 1
4...River sand.

Claims (1)

[Claims] 1. A method for injecting a drug, which comprises vaporizing solid carbonic acid in an airtight container, using the resulting pressure to pressurize the drug in an airtight container having a drug outlet, and pushing the drug out of the container.