JPH02175774A - Method of injecting adhesive and apparatus therefor - Google Patents

Abstract

PURPOSE:To inject an adhesive into a crack without difficult by keeping the temp. of the adhesive in an injector within a suitable range by heating or cooling from the outside of the injector during injecting the adhesive into the crack. CONSTITUTION:When an adhesive is injected into a crack occurred in a building of concrete, stone, brick, etc., under an injection pressure of 20kg/cm<2> or lower with an injector, the temp. of the adhesive in the injector is kept between 5-70 deg.C by the use of a heating or cooling medium installed on the outside of the injector. Thus, the increase in viscosity of the adhesive caused by the temp. variation with time is prevented, and even in winter the adhesive is injected smoothly without reducing the injection speed, whereas an excess temp. increase of the adhesive is also prevented, enabling the adhesive to be effectively injected without an excessive reduction of the curing time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive injection method and an apparatus used therefor. For more information, see Concrete and Stone.

Cracks or mortar that occur in structures made of bricks, etc. 1
20 kg/crA for floating tiles etc.
The present invention relates to a method for injecting an adhesive at an injection pressure below (gauge pressure, the same applies hereinafter) and an injector used therefor.

The present invention is a method for repairing these cracks or "lifts" (hereinafter simply referred to as cracks), in which adhesive is injected into the cracks using a syringe at an injection pressure of 20 kg/cd or less. and 20 kg
It can be used with various types of syringes that inject adhesive at an injection pressure of /cd or less.

[Conventional technology]

Conventional methods for injecting adhesive into cracks include: ■ press-fitting with a pump, ■ utilizing the restoring force of an elastic body, and ■
A method of pressurizing with compressed gas (method using solid carbonic acid - including JP-A-63-47411) is known, but
Among these, methods ① and ① are widely used.

The method (2) can be roughly divided into two: (■-a) a method that utilizes the contraction force of an elastic body such as rubber, and (■-b) a method that utilizes the restoring force of a spring.

(■-a) Implementation of the method Mr. B pasted a metal frame with a rubber sheet attached onto a substrate such as concrete to cover the crack, and applied adhesive between the substrate and the rubber sheet. A method in which adhesive is injected into the crack to inflate the rubber sheet, and the adhesive is injected into the crack using the shrinkage and restoring force of the rubber (rCCR squeeze method - injection pressure: 3 kg/cm2 or less 1 Nitto Kagaku Kogyo ■); A method in which adhesive is press-fitted into the inside of a rubber balloon attached to a pipe, the balloon is inflated, and the adhesive is injected into the crack using the contraction force of the rubber (rDD Bixue method j-injection pressure: 3 kg/
CD and below, Shaw Pond Construction■), etc.

In addition, as an embodiment of method (■-b), when installing fixedly in a crack, a syringe-shaped injector nozzle is fixed in communication with the pipe, and a bellows-shaped carburetor controller containing adhesive and a spring are set inside the injector. Then, the adhesive is press-fitted into the crack using the restoring force of the spring ("microcapsule method" - injection pressure: 5 kg/c)
m2 or less, ■microcapsules), etc.

Next, as method (2), the adhesive is press-fitted into a sealable pressure-resistant container attached to a pipe fixed to the crack, and the compressed air pressure inside the container is used to inject the adhesive into the crack. Method (rSK grout plug method) - Injection pressure: 3 kg/cm2 or less.

Sekaicho@) etc.

In addition, as for the method (2) using solid carbonic acid, adhesive and solid carbonic acid are filled in a sealable pressure-resistant container attached to a pipe fixed to the crack, and the pressure inside the container increases due to sublimation of the solid carbonic acid. Method of injecting adhesive into cracks ("dry ice method" - injection pressure: 18 kg/cm2 or less9
Nitto Chemical Industry ■).

In these methods (■) and (■), the injection pressure is 20 kg/cm so that the adhesive can be injected even into minute cracks.
Their common feature is that they are injected at low pressures below d and over a long period of time.

[Problem that the invention seeks to solve]

However, each of the above-mentioned injection methods requires a low injection pressure, and is therefore limited to low-viscosity adhesives that can be used as injection adhesives. In addition, the viscosity of the adhesive generally increases as the temperature decreases, so at low temperatures,
Particularly in winter, as the temperature of the adhesive decreases due to the influence of outside air temperature, the injection performance deteriorates, and there is a problem in that the adhesive is not injected sufficiently into not only fine cracks but also large cracks.

Also, since it is a method of injecting adhesive over time,
Adhesives with a slow curing speed must be used, but due to rising temperatures and the effects of direct sunlight, especially in the summer, the temperature of the adhesive in the syringe increases, increasing the curing speed. Therefore, there are problems in that the viscosity of the adhesive in the syringe becomes high and the injection speed decreases or the adhesive hardens within the syringe when the adhesive is not sufficiently injected into the crack.

[Means for solving problems]

As a result of various studies to improve these problems, the inventors of the present invention discovered that the adhesive can be injected while maintaining the temperature of the adhesive inside the syringe within an appropriate range by heating or cooling the syringe from the outside. This method prevents the viscosity of the injection adhesive from increasing due to temperature changes over time due to the influence of outside temperature, and enables good injection even in winter without slowing down the adhesive injection speed. Prevent the adhesive from rising excessively and avoid excessively shortening the curing time of the adhesive (
They discovered that adhesive can be effectively injected and completed the present invention.

The first invention of the present invention is ``In a method of injecting adhesive into a crack using a syringe at an injection pressure of 20 kg/c or less, a heating agent or a refrigerant is applied to the outer peripheral surface of the syringe. An adhesive injection method characterized by injecting while maintaining the temperature of the adhesive in the syringe in the range of 5 to 70'C by heating or cooling the syringe with an attached syringe.
", and the second invention is "20 kg/cm2 in the crack part.
An adhesive with a heating agent or refrigerant attached to the outer circumferential surface of the container to maintain the temperature of the adhesive in the syringe within the range of 5 = -70°C, which is used when injecting adhesive at the following injection pressure. ``Medicine injector,'' respectively.

In the present invention, the pressure for injecting the adhesive into the crack is 2
0 kg/cd or less, preferably 5 kg/cd
d or less, more preferably 1 kg/ctl or less, and the practical range is 0.5 to 1 kg/cd.

Examples of the syringe used in the present invention include various types of syringes used in the method (1) or (2) above.

The viscosity range of the adhesive when injected into the crack is 100.
000 to I Cps, preferably 20,000 to 1
It is desirable to maintain it at 3,000 to 1 cps, more preferably 3,000 to 1 cps.

In the present invention, the temperature of the adhesive in the syringe is not uniformly determined depending on the type of adhesive, but it is preferably maintained in the range of 5 ° C to 70 ° C, preferably in the range of 20 to 50 ° C.
If the temperature is below 5°C, the viscosity of the adhesive will be high and the injection performance will be poor. On the other hand, when the temperature exceeds 70"C, the curing reaction when the adhesive is organic or the hydration reaction when the adhesive is inorganic is accelerated, the viscosity of the adhesive increases or gelation occurs, and the pot life increases. This will result in insufficient injection of adhesive into the crack.

Note that if the syringe is filled with an adhesive maintained at a temperature in the range of 20 to 50°C in advance, the viscosity will be appropriate and the curing time can be maintained for a long time, resulting in even better injection results.

Another method of heating the adhesive in the syringe is to use equipment that uses electric heat or infrared rays. However, in normal repair work that uses a large number of syringes and requires controlling the injection volume for each syringe, it is difficult to install such equipment for each syringe. Since electricity is used, safety considerations must be taken, and it is inconvenient to replenish adhesive.

In the present invention, as a warming agent attached to the outer peripheral surface of the syringe in order to maintain the adhesive inside the syringe at an appropriate temperature, '+yJ material which generates heat through a chemical reaction is used.

Examples of substances that generate heat in chemical reactions include 1) substances that generate heat when in contact with water, 2) substances that generate heat due to neutralization reactions between acids and bases, and 3) substances that generate heat due to oxidation reactions.

1) Substances that generate heat when in contact with water include substances that generate heat when hydrated or dissolved in water; examples of substances that generate heat when hydrated include hydraulic cements such as Portland cement and rapid hardening cement, or hemihydrate gypsum. , anhydrite, quicklime, etc. Substances that generate heat when dissolved in water include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkali metal sulfates or carbonates such as sodium sulfate and sodium carbonate. Examples include salts, chlorides of alkaline earth metals such as calcium chloride, mineral acids such as sulfuric acid, and powdered detergents containing Glauber's salt. Depending on the combination, two or more of these may be used as a mixture. .

Wrap the substance that generates heat when it comes in contact with water with water-absorbing and water-retaining material such as cotton cloth, gauze, or a piece of absorbent cotton paper, impregnate it with water, and attach it to the outer circumferential surface of the syringe using adhesive tape or the like. Attach.

2) When using a substance that generates heat due to the neutralization reaction between an acid and a base, use a combination of a substance that generates hydrogen ions and a substance that generates hydroxide ions in an aqueous solution.

Acids include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, and other substances that produce hydrogen ions in aqueous solution; bases include:
Substances that generate hydroxide ions in aqueous solution, such as sodium hydroxide, potassium hydroxide, and lithium hydroxide, can be used directly or
Alternatively, it can be used as an aqueous solution at an appropriate concentration.

Mix an acid or/and a base with a water retention agent such as polyacrylic acid gel, polyacrylamide gel, Aerosil, white carbon, etc. in an appropriate ratio, put the appropriate amount into a bag, etc., and attach adhesive tape, etc. to the outer circumference of the syringe. Attach using.

It is also possible to wrap the acid and the base separately and attach them, and as the adhesive injection progresses, the parts of the acid package and the base package that come in contact with each other are torn to mix the contents.

3) When using a substance that generates heat due to oxidation reaction,
The ferrous oxide is wrapped in a breathable material such as gauze, and a commercially available disposable body warmer is attached to the outer circumferential surface of the syringe.

If the use of an open flame is permitted, absorbent cotton impregnated with kerosene, alcohol, etc., or solid fuel may also be used.

The amount of warming agent attached to the outer circumferential surface of the syringe varies depending on the syringe used, but is preferably an amount that can substantially cover the entire syringe.

Furthermore, in the present invention, solid carbonic acid, ice, water, or the like is used as a refrigerant attached to the outer peripheral surface of the syringe in order to maintain the adhesive inside the syringe at an appropriate temperature.

Further, it is also possible to use a substance that absorbs heat when dissolved in water. Such substances include 1. Potassium chloride, sodium chloride, magnesium sulfate, sodium bicarbonate,
Examples include potassium hydrogen carbonate, potassium hydrogen sulfate, acrylamide crystals, and N-methylol acrylamide.

In order to efficiently maintain temperature for a long time, it is necessary to cover the area around the heating agent or refrigerant attached to the outer circumferential surface of the injector with a heat insulating material to prevent heat radiation or heat intrusion from the outside. preferable.

Insulating materials include various synthetic resin foams such as expanded polystyrene, polyurethane foam, phosphor resin foam, and phenol resin foam, and a piece of cotton cloth.

Cardboard, cellulose fiber, animal hair felt, asbestos, glass wool, rock wool, polyethylene film, soft synthetic fibers, cork, and other natural or synthetic fiber materials such as vegetable, animal, and mineral materials, as well as sheets, perlite, and granules. Foam glass, white carbon, Aerosil, etc. can be used.

The amount of heat insulating material used is preferably an amount that can cover the heating agent or refrigerant attached to the outer circumferential surface of the injector, and it is preferable to cover it in multiple layers.

In the present invention, various organic and inorganic adhesives can be used as the injection adhesive.

Various organic adhesives include epoxy resin, unsaturated polyester resin, vinyl acetate resin, styrene-butadiene rubber, polyacrylic ester, ethylene-vinyl acetate, and isocyanate. can be mentioned.

Further, examples of the inorganic adhesive include hydraulic cements, alkali silicates, colloidal silica, alumina sol, etc., and one or more of these can be used in the form of milk or slurry.

The above-mentioned hydraulic cements include ordinary Portland cement and moderate heat Portland cement.

Portland cements such as early-strength Portland cement, low-heat Portland cement, sulfate-resistant Portland cement, high iron oxide type Portland cement, white Portland cement, mixed cements such as blast furnace cement, silica cement, flyanosh cement, masonry cement, and colloidal cement. special cements such as alumina cement, alkaline calcium salts such as quicklime and slaked lime, or sodium sulfate and potassium sulfate.

Examples include a mixture of an alkali metal or alkaline earth metal sulfate such as calcium sulfate and at least one of blast furnace slag, silica, or fly ash.

Various cement admixtures can also be added to these hydraulic cements.

As an admixture, styrene-butadietane rubber (SBR
), various polymer dispersions such as polyacrylic acid esters and ethylene-vinyl acetate, water reducing agents and fluidizing agents such as lignin sulfonate-based, naphthalene sulfonate-based, and oxyorganic acid salt-based products, and lower alcohol alkylene oxide adducts. , ether type nonionic surfactants, calcium sulfoaluminate mixtures, tricalcium aluminate mixtures, alumina cement mixtures, various shrinkage regulators, antifreeze/cold resistant agents, antifoaming agents, viscosity modifiers, etc. are used. [For details, see Yoshio Kasai et al., [Admixtures for Cement and Concrete] (Gijutsu Shoin, May 15, 1986)
(Published on 1st edition)).

〔Effect of the invention〕

The present invention has the following effects.

(1) Since the viscosity of the adhesive filled in the syringe can be maintained at an appropriate level, it is possible to use adhesives whose viscosity increases as the temperature decreases in the low-pressure injection method.
Particularly, the adhesive can be injected into cracks well even in winter when the air temperature and substrate temperature are low.

(2) It prevents the temperature of the adhesive filled in the syringe from rising excessively, and the curing time can be maintained for a long time without excessively shortening the curing time of the adhesive. can be injected into the crack. especially,
Even in summer, if the adhesive in the syringe is not sufficiently injected into the crack, the hardening or gelation of the adhesive inside the syringe may be accelerated, increasing the viscosity and reducing the injection speed, or even causing the adhesive to harden inside the syringe. You can use the adhesive effectively without wasting it.

(Example〕 Next, the present invention will be explained with reference to Examples and Comparative Examples.

Examples A-1 to A-18 and Comparative Examples A-1 to A-9° Sand stop (S/C) 3/1. Temporary (600x600) made using concrete mixed with water ratio (W/C) 0.65
The surface of the sample (x30 mm) was polished with emery cloth (1180) to remove laitance. The polished surfaces of two concrete plates were faced to each other with an interval of 0.1 mm, and the periphery was fixed with putty-like epoxy resin. Injectors of the various types shown in Table 1 were attached to the center of one side with a length of 6001 m, and holes with a diameter of about 2Ilv11 were provided at the corners of each opposing side to vent air.
The entire area was sealed with epoxy resin.

A thermocouple was inserted between the injector and the concrete plate to measure the temperature of the adhesive.

After leaving the adhesive and test equipment to be used in a low-temperature room adjusted to a temperature of 3 to 5° C. overnight, a pouring test was conducted in the low-temperature room. The injection adhesive was heated to 20° C., filled into a syringe, and tested.

Ordinary Portland cement, blast furnace cement, and fly ash cement as inorganic adhesives were each pulverized using a planetary ball mill (manufactured by Fritsch 2, West Germany), and those having a maximum particle size of 40 μm or less were used.

The warming agent was added as follows.

In Examples ^-1 to A-8 and A-15 and 16, each powdered or granular warming agent in the amount shown in Table 1 was wrapped in gauze, impregnated with water, and applied to the outer peripheral surface of the syringe. Attached using craft tape.

Separately, 150 g each of powdered silica (trade name "Aerosil" 2 Nippon Aerosil ■) was impregnated with 300 g each of 20% by weight aqueous solutions of sulfuric acid, hydrochloric acid, sodium hydroxide, and potassium hydroxide, and a grease-like warming agent impregnated product was Made by l.

In Examples A-9 and A-10, 450 g of the sulfuric acid aqueous solution impregnated with the temperature increased by the above-mentioned so-called production was placed in a plastic bag and attached to the outer peripheral surface of the syringe.

In Examples A-11, 12, 17, and 18, 450 g of each of the warming agent impregnated materials were mixed and kneaded in the combinations shown in Table 1, and the mixture was placed in a plastic bag and wrapped with craft tape around the syringe. It was installed using.

Furthermore, in Examples A-13 and 14, a disposable body warmer (size: 13.5×10c+s) (trade name: "Onpax", Mycol hand warmer ■) was directly attached to the outer circumferential surface of the syringe using craft tape.

The amount of heat insulating material was determined through preliminary tests and was determined to be sufficient to maintain heat.

The injection test was carried out for 20 minutes according to the respective usage of each syringe.
The adhesive was injected at an injection pressure of kg/cd or less, and the amount of adhesive injected 40 minutes after the start of injection was measured to determine the injection results.

Table 1 shows the conditions and results of each test.

When no heating agent was used, the temperature of the adhesive dropped rapidly and the amount of injection was insufficient, resulting in poor injection results (Comparative Examples A-1 to -9). In Examples A-1 to A-18, which were heated with a heating agent, the amount of adhesive injected was significantly increased compared to the corresponding comparative example, and the injection results were good. Furthermore, when the heating agent was surrounded by a heat insulating material, the adhesive injection performance was further improved.

Examples B-1 to B-12 and Comparative Examples B-1-B-6° Adhesive injection test was conducted in the same manner as in Example A-1, except that the interval between the polished surfaces of the concrete plates was 0.05 m. I prepared the equipment.

The adhesive used and the test equipment were left overnight in a high-temperature chamber adjusted to a temperature of 45 to 50°C, and then injection tests were conducted in the high-temperature chamber.

Injection adhesives were tested by mixing the base agent and hardening agent, and by kneading the cement-based adhesive with water, leaving them for 30 minutes, then filling them into a syringe.

Ordinary Portland cement as an inorganic adhesive was treated according to Example A-1.

The refrigerants used were as shown in Table 2, and each was placed in a plastic bag and attached around the syringe using craft tape.

The amount of heat insulating material used was determined through preliminary tests and was sufficient to effectively retain the temperature.

Adhesive was injected with an injection pressure of 20 kg/cm 2 or less according to the usage instructions for each syringe, and the injection results were determined by measuring the amount of adhesive injected 2 hours after the start of injection.

Table 2 shows the conditions and results of each test.

In comparative examples that did not use a refrigerant, the organic adhesive progressed to harden during injection and the viscosity increased, resulting in comparative examples B-1 to B.
-3), and Comparative Example B-4, which does not gel with inorganic adhesives.
~B-6), the injection results were poor in all cases.

On the other hand, in Examples B-1 to B-12, which were cooled with a refrigerant, the injection amount of adhesive was significantly increased compared to the corresponding comparative example, and the injection results were good. Also,
When the refrigerant was surrounded by a heat insulating material, the adhesive injection performance was further improved.

Claims (1)

[Claims] 1) In a method of injecting adhesive into cracks using a syringe at an injection pressure of 20 kg/cm^2 or less, a heating agent or a refrigerant is applied to the outer peripheral surface of the syringe. A method for injecting an adhesive, which comprises heating or cooling an attached injector to maintain the temperature of the adhesive within the injector within a range of 5 to 70°C. 2) A heating agent or coolant to maintain the temperature of the adhesive in the syringe in the range of 5 to 70°C, which is used when injecting the adhesive into the crack at an injection pressure of 20 kg/cm^2 or less. Adhesive syringe attached to the outer circumferential surface of the container.