KR102635179B1 - Non-silicate and non-cement inorganic grout composition and eco-friendly grouting process using the same - Google Patents

Abstract

In order to solve these conventional technical problems, the present invention does not contain cement, which fundamentally causes environmental problems, and does not use silicates of the sodium silicate type that weaken durability, and at the same time improves the bleeding rate, gelation time, or strength. It relates to a non-silicic acid-free inorganic grout material with excellent physical properties such as shrinkage rate, chloride ion penetration resistance, and whitening resistance, and an eco-friendly grouting method using the same.

Description

Non-silicate and non-cement inorganic grout composition and eco-friendly grouting process using the same}

The present invention relates to a non-silicate cement-free inorganic grout material and an eco-friendly grouting method using the same.

At civil engineering sites, water protection and ground reinforcement are often required during the construction of underground structures or tunnel construction. For example, the foundation ground cannot accommodate the increased load due to the expansion or remodeling of high-rise buildings in urban areas. There are many cases.

In particular, tunnels not only form the nation's infrastructure, but also many tunnels pass through roads, so it is essential that tunnels also maintain their original state during the design life of the road. Nevertheless, structural or material performance deterioration of tunnels frequently occurs due to environmental factors or external forces, and a lot of costs are spent on maintenance and repair of tunnels.

For this reason, interest in tunnel cavity backfilling materials is increasing. The existing tunnel cavity backfilling materials often have back cavities that should not be present due to material separation, bleeding, and difficulties in construction due to on-site mixing. This occurs and the cavity at the back of the tunnel acts as a cause of shortening the life of the tunnel due to cracks in the lining, stress concentration, water leakage, etc.

In addition, water in the ground penetrates into cracks existing in underground structures and facilities, causing internal reinforcement corrosion and expansion of cracks, which reduces durability or causes water leaks through cracks.

In this way, the tunnel structure (especially the lining concrete) must be integrated with the surrounding rock that forms the tunnel, and when designing a tunnel, the tunnel structure must behave in an integrated manner with the surrounding rock even in the face of external shocks such as earthquakes. Therefore, the presence of a cavity in the back of the tunnel is important in the design. Although it is fundamentally not allowed in construction, the tunnel structure is separated from the surrounding rock due to the often occurring back cavity, which acts as a flow path for groundwater, seriously affecting safety in the event of an external impact.

In particular, the presence of cavities in the ceiling reduces usability by causing deterioration due to groundwater accumulation, and may even cause loosening of the upper ground or longitudinal cracks in the lining ceiling.

As seen above, if a road, bridge, or building is placed on soft ground, which is composed of soft clay or organic soil and cannot support the upper structure, the amount of settlement will be excessive and safety problems will arise due to insufficient bearing capacity. Since this occurs, grouting methods are generally used to reinforce weak ground to prevent these problems from occurring.

In this way, the grouting method is used in civil engineering sites for the purposes of improving the grout's ability to withstand consolidation, reducing the permeability coefficient to secure water resistance, reducing land compressibility, and reducing noise and vibration generated during construction to shorten the construction period. there is.

This grouting method has been recognized for its effectiveness and is widely used for various purposes such as ground reinforcement and water blocking, foundation pile formation, soft ground improvement, structure reinforcement, tunnel reinforcement and water blocking, etc. The most common grout injection method in Korea is a chemical liquid system. The LW (Labiles Wasserglass) method, the SGR (Space Grouting Rocket System) method, and the suspension-based Portland cement milk injection method are evaluated as excellent in terms of economic efficiency, and are being widely used in construction.

The LW method is a representative 1.5 shot injection method that mixes water glass (soda silicate) and cement milk. It is mainly capable of fully penetrating into gravel and sand layers, and is used for the purpose of preventing subsidence or strengthening the ground by injecting into soft clay soil and silt layers. The LW method is inexpensive and the injection process is easy, but it has the disadvantages of not being able to use a complex injection method through complete/quick setting, and of reducing strength and environmental pollution due to water glass dissolution.

The SGR method is a representative 2.0 shot injection method that uses a mixed suspension of water glass, quick-setting agent, and cement. By using a three-tank type stirring device, continuous complex injection of rapid and complete injection agents is possible, making it easy to level the ground. Injection is possible mainly in both cohesive and sandy soils, so it is applied to improving soft ground. However, when water glass is used, the hydration reaction of the mixed cement is inhibited, making it difficult to develop long-term strength, and over time, water glass leaching occurs, resulting in a decrease in compressive strength and material separation, making it unsuitable for long-term ground water blocking performance. there is.

The grouting methods reviewed above and the various other grouting methods developed to date are mostly methods that use cement as the main material and also include soda silicate, which fundamentally causes environmental problems and has limitations in terms of durability.

In relation to causing environmental problems, the problem of global warming has recently become more serious, and cement, which has been used for a long time in the construction field, inevitably emits a large amount of carbon dioxide, a warming substance, during the manufacturing process. It is becoming.

Specifically, in the process of manufacturing cement, about 729-911 kg of carbon dioxide is emitted per ton, and according to the Korea Cement Association's announcement that the amount of cement produced in 2015 was about 36 million tons, this results in at least 2,600 tons of carbon dioxide. As an enormous amount of carbon dioxide was generated, ranging from 1 million to 32 million tons, there is an urgent need to develop technology to replace the use of cement in the grouting method.

In this oligopoly, recycled resources such as fly ash or blast furnace slag are used as alternative materials that can reduce the amount of cement used at construction sites, but in the field of grouting quick-setting materials, it is difficult to control strength issues and gelation (or setting) time. It is currently being used only in a very limited way.

In addition, in relation to its weakness in terms of durability, most of the conventional solution-type or suspension-type grouting chemicals discussed above use silicates of the sodium silicate type, which contain a large amount of sodium, and a large amount remains in the final solidified body. The resulting sodium (Na) reacts with the moisture contained in the underground and causes a leaching phenomenon in which it escapes from the solidified body. This not only makes it impossible to provide waterproofing due to a decrease in the volume of the solidified material, but also damages the high-strength solidified material in the future. This causes a problem that drastically reduces the durability.

Looking in more detail, most of the existing injection methods are grout materials and methods using water glass, where water glass is a term for sodium silicate or an aqueous solution of sodium silicate that can act as an alkaline activator, Na ₂ Oㅇ nSiO ₂ ㅇmH ₂ O It is an industrial material with a molecular formula of .

The content, composition, and characteristics of this water glass vary depending on the amount of water it contains. Not only does the pH change depending on the molar ratio or concentration, but it also exhibits the property of gelling and hardening due to acids, metal ions, or polymers, so it is used in the industry as adhesives and castings. , anhydrous silicic acid, is used as a civil engineering material.

When mixed with cement-based powder and injected into the ground, water glass has the advantage of having a large instantaneous water blocking effect and high permeability due to a low viscosity of 2-3 cps, but the strength of the consolidated soil mixed with water glass grout is low and its strength is lost due to leaching by the surrounding water. It has the fundamental disadvantage of causing degradation. In addition, grout using water glass not only has its gelling performance and strength development performance reduced by more than 30% due to low water temperature and air temperature in the winter, but also can dissolve human skin, so special care must be taken when handling it.

Therefore, it is necessary to develop a grout material that does not contain cement, which fundamentally causes environmental problems, and does not use silicates such as sodium silicate, which weakens durability, and at the same time has excellent physical properties such as bleeding rate, gelation time, strength, and shrinkage rate. It's a situation.

1. Korean Patent No. 10-0209247 2. Korean Patent No. 10-1988460 3. Korean Patent No. 10-1422094 4. Korean Patent Publication No. 10-2007-0114961

In order to solve these conventional technical problems, the present invention does not contain cement, which fundamentally causes environmental problems, and does not use silicates of the sodium silicate type that weaken durability, and at the same time improves the bleeding rate, gelation time, or strength. We aim to provide a non-silicic acid-free inorganic grout material with excellent physical properties such as shrinkage rate, chloride ion penetration resistance, and whitening resistance, and an eco-friendly grouting method using the same.

One aspect of the present invention is (a) cement-free agent A containing 20-70% by weight of slaked lime and 30-80% by weight of desulfurized gypsum, and (b) 30-60% by weight of calcium sulfuraluminate, It relates to a non-silicate cementless inorganic grout material characterized by containing a non-silicate B agent containing 35-67% by weight of slag fine powder and 2-6% by weight of soda aluminate.

Another aspect of the present invention is the step of (A) preparing solution A by adding agent A containing slaked lime and desulfurized gypsum to prepared water for solution A and dispersing it; (B) preparing solution B by adding agent B containing calcium sulfuraluminate, fine slag powder, and sodium aluminate to prepared water for solution B and dispersing it; and (C) mixing the liquid A and the liquid B to form a grout material, which relates to a grouting method characterized by using a non-silicate cement-free inorganic grout material.

According to various embodiments of the present invention, it does not contain cement, which fundamentally causes environmental problems, and does not use silicates of the sodium silicate type that weaken durability, and at the same time improves physical properties such as bleeding rate, gelation time, strength, and shrinkage rate. It is excellent in chloride ion penetration resistance and whitening resistance.

Below, we will look at various aspects and various implementations of the present invention in more detail.

In this specification, other parts may be added to expressions such as 'includes', 'has', 'consists of', 'consists of', etc., as long as 'only' is not used.

Additionally, in this specification, when an element is expressed in the singular, it also includes plural elements, unless specifically stated otherwise.

In addition, the numerical values or numerical ranges described in this specification are interpreted to include the margin of error even if not explicitly stated otherwise.

Additionally, in this specification, the expression “X to Y” indicating a numerical range means “X to Y or less.”

The terms used in the present invention are only used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “comprise” are intended to designate the presence of the described features, numbers, steps, operations, components, parts, or combinations thereof, but are not intended to indicate the presence of one or more other features or It should be understood that this does not exclude in advance the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless specifically defined differently, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless clearly defined in the present application, should not be interpreted as having an ideal or excessively formal meaning. .

The present invention, an environmentally friendly and highly durable inorganic ground stabilizer, was developed to solve the above-mentioned problems. The purpose of the present invention is to not only eliminate the risk of environmental pollution caused by solidified water, but also to improve the setting and hardening speed of cement. The goal is to provide an environmentally friendly and highly durable inorganic ground stabilizer that can be adjusted and at the same time has not only short-term compressive strength but also long-term compressive strength and long-term durability.

In other words, the present invention is an eco-friendly ground waterproofing solution using industrial by-products without using cement, which is the main cause of global warming and is the most widely used grout material so far, and which is made by generating large amounts of carbon dioxide, and soda silicate, which is unsuitable as a grout material due to alkali leaching. It relates to an inorganic grout composition. Specifically, it prevents the problem of leaching by groundwater by completely excluding the previously used water glass, and uses a powdered mineral quick-setting agent that does not use any cement that may pose environmental problems, and desulfurization that is an industrial by-product. It relates to an eco-friendly inorganic grout material composition as a ground injection material mainly made of gypsum and slag.

One aspect of the present invention devised in this way is (a) a cement-free agent A containing 20-70% by weight of slaked lime and 30-80% by weight of desulfurized gypsum, and (b) 30-60% calcium sulfuraluminate. It relates to a non-silicate cement-free inorganic grout material, characterized in that it contains a non-silicate B agent containing 35-67% by weight of slag fine powder and 2-6% by weight of soda aluminate.

In one embodiment, either one of the agent A and the agent B or each includes bentonite having a swelling degree of 10 or more, and 3-4 kg of the bentonite is included per 350 kg of the agent A or the agent B.

Desulfurized gypsum and slag fine powder are by-products of the oil refining and steel industries, respectively, and not only have the advantage of recycling circular resources, but also solve problems caused by the use of cement and silicic acid, and interact with other ingredients to improve bleeding rate, gelation time, and It can also be a great advantage in securing excellent physical properties such as strength and shrinkage rate. In addition, calcium sulfuraluminate acts as an inorganic mineral quick-setting agent and reacts with lime and water to produce ettringite, and soda aluminate acts as a water-soluble inorganic gelling agent.

Another aspect of the present invention is the step of (A) preparing solution A by adding agent A containing slaked lime and desulfurized gypsum to prepared water for solution A and dispersing it; (B) preparing solution B by adding agent B containing calcium sulfuraluminate, fine slag powder, and sodium aluminate to prepared water for solution B and dispersing it; and (C) mixing the liquid A and the liquid B to form a grout material, which relates to a grouting method characterized by using a non-silicate cement-free inorganic grout material.

As before, when using agent A, which consists only of cement or contains a significant amount of cement, the bleeding rate, strength, and shrinkage rate cannot all be improved to a high level at the same time. Similarly, even when using agent B, which consists only of sodium silicate or contains a significant amount of sodium silicate as before, the bleeding rate, strength, and shrinkage cannot all be improved to a high level at the same time.

In one embodiment, the agent A contains 20-70% by weight of slaked lime and 30-80% by weight of desulfurized gypsum, and the agent B contains 30-60% by weight of calcium sulfuraluminate, 35-67% by weight of slag fine powder, Contains 2-6% by weight of soda aluminate. If the composition of agent A or agent B is outside any of the above ranges, the produced grout material may precipitate white precipitates when exposed to seawater for a long period of time, and if the composition of agent A or agent B satisfies all of the above ranges. In that the whitening test results show qualitatively different results, the tonal sounds of Agents A and B above can be said to be important.

In another embodiment, 100-600 kg of agent A is added based on 500 L of liquid A, and 100-600 kg of agent B is added based on 500 L of liquid B. If it is less than 100 kg, the water content is too high and the gelation time may be too long or shrinkage may occur. If it exceeds 600 kg, the water content is too low and pumping and transport may not be smooth, making it difficult to infiltrate the ground.

In another embodiment, the prepared water for solution A and the prepared water for solution B may have the same or different components, and are each independently water or bentonite with a swelling degree of 10 or more per 500 L of solution A or 500 L of solution B. It contains 3-40kg of water per serving. In a preferred embodiment, at least one of the prepared water for solution A and the prepared water for solution B is water containing 3-40 kg of bentonite with a swelling degree of 10 or more per 500 L of solution A or per 500 L of solution B. In the most preferred embodiment, the prepared water for solution A and the prepared water for solution B are water each containing 3-40 kg of bentonite with a swelling degree of 10 or more per 500 L of solution A or per 500 L of solution B.

In this way, it is preferable to prepare solution A or solution B using prepared water containing bentonite, and in addition, chloride ion penetration resistance depends on whether the order of adding agent A or agent B is followed by adding bentonite first. In that qualitatively different results are shown, the above input or addition order can be said to be important. If the amount of bentonite used is less than 3kg, material separation may occur due to bleeding, and if it exceeds 40kg, the viscosity may be too high and problems may occur in pumping transfer.

In another embodiment, the agent A further includes 0.1-10% by weight of citric acid based on the total weight of the slaked lime and the desulfurized gypsum. Alternatively, agent B further includes 0.1-10% by weight of citric acid based on the total weight of the calcium sulfuraluminate and the slag fine powder. Or, the agent A further contains 0.1-10% by weight of citric acid based on the total weight of the slaked lime and the desulfurized gypsum, and the agent B also contains 0.1-10% by weight of citric acid based on the total weight of the calcium sulfuraluminate and the slag fine powder. Contains an additional 10% by weight.

When water-insoluble powder is dispersed in water, material separation may occur, so it is advisable to use highly swellable bentonite to prevent material separation and bleeding during the process of injection and transport into the ground for grouting. In addition, a curing retardant such as citric acid can be used to vary the gelation time.

In another embodiment, the mixing volume ratio of the liquid A and the liquid B is 1:1.5 to 1.5:1, preferably 1:1.2 to 1.2:1, and more preferably 1:1. If it is outside the above range, stable physical property values may not be obtained.

As seen above, in the present invention, desulfurized gypsum, an environmentally friendly inorganic material and an industrial by-product generated in an oil refinery, is used as a cement substitute. Desulfurization powder is a substance that is generated in large quantities during the crude oil refining process and is used for various purposes. It is an active powder with excellent fineness through a dry grinding process and is very suitable as a grout material. In the composition of agent A, if it is less than 30% by weight, the gel strength may be weakened, and if it exceeds 80% by weight, the gelation time may be slow.

Slag is a by-product generated in the steelmaking process of steel companies, and the fine powder obtained by pulverizing it plays a significant role in improving durability and strength when mixed with cement. In the composition of agent B, if it is less than 35% by weight, long-term strength development may be weakened, and if it exceeds 67% by weight, the initial strength may be weakened.

Calcium sulfur aluminate (CSA) used in the composition of the present invention is an inorganic mineral quick-setting compound mainly composed of 2CaOㅇ3Al ₂ O ₃ ㅇCaSO ₄ and is a hydrated product by reaction with free lime, lime and water. It is a mixed material that creates ettringite and gives it the characteristics of fast hardening, high strength, and expansion, and is used for various purposes depending on its composition. In the composition of agent B, if it is less than 30% by weight, the gelation time may be delayed and strength development may be delayed, and if it exceeds 60% by weight, it may be a factor in increasing the cost.

When using an eco-friendly inorganic grout composition for ground water blocking using industrial by-products according to the present invention configured as described above, water glass, which causes various problems, is completely excluded and cement, which may have environmental problems, is not used. Instead, powder type grout composition is used. By using mineral quick-setting agents and industrial by-products such as desulfurized gypsum and slag, the problem of leaching caused by groundwater in the ground and environmental pollution can be solved.

Slaked lime used in Agent A of the present invention is involved in promoting initial hardening and controlling gelation time. In the composition of Agent A, if it is less than 20% by weight, the gel time and initial strength may be weakened, and if it exceeds 70% by weight, it may gel too quickly and the long-term strength may be weakened.

Sodium aluminate is used as a strength development accelerator, and if the amount used in solution B is less than 2% by weight, strength may not be developed, and if it exceeds 60% by weight, there may be no added effect.

In addition, according to the present invention, by controlling the pozzolanic reaction and long-term hydration reaction of these materials, the gel time, which is important in ground water grout, can be controlled over a wide range, thereby satisfying complex injectability using complete or rapid setting, and strength control by controlling the water ratio. can facilitate.

Grout materials, which are made of water-insoluble powder rather than liquid or water-soluble substances such as sodium silicate, do not dissolve in water and are dispersed by stirring, but then sink immediately due to the difference in specific gravity, resulting in an uneven state. In the case of a two-component grout material, liquid A and liquid B must meet uniformly at the designed ratio so that the originally planned physical properties can be realized in the field, as shown in the theoretical results in the laboratory. However, if this phenomenon occurs, the desired physical properties are not revealed due to a non-uniform reaction. There are cases where this does not work.

Depending on the conditions of the construction site for ground injection and the depth of injection into the ground, the length of the pressure delivery pipe may exceed 2-3 km. Liquid A and Liquid B are mixed with water in powder form within the pipe. Due to the difference in specific gravity, the high specific gravity inorganic material powder inevitably settles and accumulates on the bottom of the transfer pipe or deteriorates into an uneven state. Therefore, the characteristic of the inorganic grout material composition of the present invention is that it has a swelling degree of 10 to prevent this phenomenon. The above bentonite can be used at 5-40 kg per 1 m ³ of ground injection material.

Preferably, bentonite with a swelling degree of 20 or more is used, and more preferably, a bentonite with a swelling degree of 30 or more is used. The higher the swelling degree, the lower the amount used. If the swelling degree is 30 or higher, it is advisable to use it in the range of 5-20kg per ^1m3 . If it is less than 5kg, the bleeding rate may be high and material separation may increase, and if it exceeds 40kg, the viscosity of the solution is too high, making pumping and injection difficult, and problems with pumping may occur.

When preparing liquid A and liquid B separately without mixing the bentonite with the grout composition of the present invention, it is important to first add it to the mixing water and disperse it, and then add each of the A and B agents.

In addition, the present invention is characterized in that it does not use fly ash components, which are generally widely used in the composition of inorganic grout materials. The fly ash component has a significant material cost reduction effect, but the physical properties and long-term durability of the grout material are very weak compared to slag fine powder. In particular, due to the nature of the incineration ash called fly ash, the physical properties vary greatly depending on the composition and quality of the coal used for incineration, whereas the slag fine powder generated during the steelmaking process not only has uniform physical properties, but also has potential hydraulic and alkali absorption properties. It forms calcium aluminate hydrate and calcium silicate, which plays a significant role in developing long-term strength and long-term durability.

Also, a retardant such as citric acid can be used as a gelation time regulator. Ground injection material is used in situations where the gelation time must be adjusted in various ways depending on the situation in which it is injected into the ground, for example, the presence or absence of groundwater, the degree of groundwater flow, the size of cavities or pores, the scope of injection into the ground, the state of bulb formation, etc. Can be used as a time regulator. The amount used can be 0-0.7% by weight of the total powder content, and if it exceeds 0.7% by weight, a problem of not developing strength may occur.

When using the soda silicate solution, which has been widely used so far in two-component grout material compositions, as agent B, since it is a low-viscosity solution B that does not use any powder, a special device is installed at the area where solution A and the two solutions are transferred and meet. Even without , liquid A and liquid B were easily mixed due to the turbulent flow formation effect of the fluid, so that liquid A and liquid B were uniformly mixed, making it easy to develop the designed physical properties. However, in the case of liquid A and liquid B, which are composed only of inorganic powders, the viscosity is high, so it is desirable to use a line mixer device at the point where the two liquids meet.

Hereinafter, the present invention will be described in more detail through examples, etc., but the scope and content of the present invention should not be construed as being reduced or limited by the examples below. In addition, based on the disclosure of the present invention, including the following examples, it is clear that a person skilled in the art can easily implement the present invention for which no specific experimental results are presented, and the patent to which such variations and modifications are attached It is natural that it falls within the scope of the claims.

In addition, the experimental results presented below describe only the representative experimental results of the examples and comparative examples, and the effects of each embodiment of the present invention that are not explicitly presented below will be described in detail in the corresponding section.

Example

Example 1

As shown in Table 1 below, solution A and solution B were prepared.

350kg of agent A, consisting of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum, was added to 390L of water to prepare 500L of solution A.

350kg of agent B, consisting of 50% by weight of calcium sulfuraluminate (CSA), 46% by weight of slag fine powder, and 4% by weight of soda aluminate, was added to 390L of water to prepare 500L of solution B.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Example 2

5kg of bentonite with a swelling degree of 30 was first added to 390L of water, stirred for about 5 minutes, and then 350kg of agent A consisting of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum was added to prepare 500L of solution A.

5kg of bentonite with a swelling degree of 30 was first added to 390L of water, stirred for about 5 minutes, and then 350kg of agent B consisting of 50% by weight of calcium sulfuraluminate, 46% by weight of slag fine powder, and 4% by weight of soda aluminate were added to make 500L of solution B. was manufactured.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Example 3

Solution A was the same as Example 2, except that instead of using agent A consisting of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum, agent A consisting of 25% by weight of slaked lime and 75% by weight of desulfurized gypsum was used. and B solutions were prepared and their characteristics were analyzed.

Example 4

Instead of using agent B consisting of 50% by weight of calcium sulfuraluminate, 46% by weight of slag fine powder, and 4% by weight of soda aluminate, 30% by weight of calcium sulfuraluminate, 65% by weight of slag fine powder, and 5% by weight of soda aluminate are used. Liquids A and B were prepared and their characteristics were analyzed in the same manner as in Example 2, except that agent B consisting of was used.

Example 5

Liquid A and Liquid B were prepared in the same manner as in Example 2, except that instead of using 350 kg of Agent A and 350 kg of Agent B, 200 kg of Agent A and 200 kg of Agent B were used. However, the volume of solution A and solution B was adjusted to 500L by adjusting the amount of water, and then the prepared solution A and solution B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Example 6

Instead of using 350kg of agent A and 5kg of bentonite to prepare solution A, 550kg of agent A and 3kg of bentonite were used to prepare solution A, and instead of using 350kg of agent B and 5kg of bentonite, 550kg of agent B and 3kg of bentonite were prepared. Solutions A and B were prepared in the same manner as in Example 2, except that they were used. However, the volume of solution A and solution B was adjusted to 500L by adjusting the amount of water, and then the prepared solution A and solution B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Example 7

Example 2, except that instead of using agent A consisting of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum, agent A consisting of 50% by weight of slaked lime, 49.5% by weight of desulfurized gypsum and 0.5% by weight of citric acid was used. In the same manner as above, liquid A and liquid B were prepared and their characteristics were analyzed.

Comparative Example 1

500 L of Liquid A was prepared by adding 350 kg of Agent A, which consists of 100% by weight of cement, into 390 L of water. 500L of solution B was prepared by mixing 250L of agent B, which consists of 100% by weight of soda silicate No. 3, with 250L of water.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Comparative Example 2

Liquid A was prepared in the same manner as in Comparative Example 1, except that 5 kg of bentonite with a swelling degree of 30 was first added to 390 L of water, stirred for about 5 minutes, and then 350 kg of Agent A consisting of 100% by weight of cement was added to prepare 500 L of Liquid A. and B solutions were prepared and their characteristics were analyzed.

Comparative Example 3

Comparison except that instead of adding 350kg of cement to 390L of water to produce 500L of Solution A, 350kg of Agent A, which consists of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum, was added to 390L of water to make 500L of Solution A. Liquid A and Liquid B were prepared in the same manner as Example 1 and their characteristics were analyzed.

Comparative Example 4

Instead of preparing 500L of solution B by mixing 250L of agent B, which consists of 100% by weight of sodium silicate No. 3, with 250L of water, 5kg of bentonite with a swelling degree of 30 was first added to 390L of water, and then stirred for about 5 minutes and then added to calcium sulfuraluminate 50. Liquid A and Liquid B were prepared in the same manner as in Comparative Example 2, except that 500 L of Liquid B was prepared by adding 350 kg of Agent B consisting of 46% by weight of slag fine powder and 4% by weight of soda aluminate. was analyzed.

Comparative Example 5

350 kg of Agent A, consisting of 18% by weight of slaked lime and 82% by weight of desulfurized gypsum, was added to 390L of water to prepare 500L of Solution A.

350kg of agent B, consisting of 28% by weight of calcium sulfuraluminate (CSA), 71% by weight of slag fine powder, and 1% by weight of soda aluminate, was added to 390L of water to prepare 500L of solution B.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Comparative Example 6

2.5kg of bentonite with a swelling degree of 30 was first added to 390L of water, stirred for about 5 minutes, and then 350kg of agent A consisting of 18% by weight of slaked lime and 82% by weight of desulfurized gypsum was added to prepare 500L of solution A.

2.5kg of bentonite with a swelling degree of 30 was first added to 390L of water, stirred for about 5 minutes, and then 350kg of agent B consisting of 28% by weight of calcium sulfuraluminate, 71% by weight of slag fine powder, and 1% by weight of soda aluminate were added to make solution B. 500L was prepared.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

Comparative Example 7

350 kg of Solution A, consisting of 50% by weight of slaked lime and 50% by weight of desulfurized gypsum, was first added to 390 L of water and stirred for about 5 minutes, then 5 kg of bentonite with a swelling degree of 30 was added and stirred for an additional 5 minutes to prepare 500 L of Solution A. .

First add 350kg of agent B, which consists of 50% by weight of calcium sulfuraluminate, 46% by weight of slag fine powder, and 4% by weight of soda aluminate, into 390L of water and stir for about 5 minutes, then add 5kg of bentonite with a swelling degree of 30 and stir for about 5 minutes. By further stirring, 500L of solution B was prepared.

The prepared liquid A and liquid B were mixed, and an experiment was conducted on the test items whose characteristics were to be measured.

(1) Bleeding rate measurement

After pouring each of the prepared solutions A and B into a 1000mL measuring cylinder according to the 1000mL scale to prevent air from entering, they are left on the table. After 3 hours of standing, the materials bleed out, settle, and the volume of water separated at the top. was measured, and the bleeding rate was calculated using the formula below.

Bleeding rate (%) = (volume of water bleed / volume of measuring cylinder (1000mL)) ㅧ 100

(2) Measurement of gelation time (gel time)

Put 350 g of liquid A in a vertical plastic bag, twist and fold the plastic bag at about the height of liquid A, add liquid B in proportion to separate liquid A and liquid B, and tighten the opening of the plastic bag. As soon as the gel time starts, release the hand that was holding between liquid A and liquid B, hold the plastic bag vertically and shake it up and down. The time (seconds) until liquid A and liquid B meet and react and stop without feeling any more fluidity. was set as the gel time.

(3) Strength measurement

To measure the strength, a specimen was made in a cubic mold measuring 50 mm x 50 mm and measured according to the compressive strength test method for KS L 5105 hydraulic cement mortar.

(4) Shrinkage rate measurement

The same specimen as the strength measurement was produced and the volume was measured with a micrometer before and after 28 days of underwater curing and air curing to confirm the rate of change in volume.

[Table 1a]

[Table 1b]

The results of measuring the above characteristics are presented in Table 2 below.

[Table 2a]

[Table 2b]

(5) Test results

As shown in the tables above, it can be seen that the grout materials manufactured in the examples are overall superior to the grout materials manufactured in the comparative examples in terms of bleeding rate, gelation time, 28-day strength, and 28-day shrinkage rate. In particular, it can be seen that there is a significant improvement in 28-day strength and 28-day shrinkage rate, and a significant improvement in bleeding rate compared to the comparative examples, except for Example 1 in which bentonite was not added. .

Looking at it in more detail, it can be seen that in the case of Example 1, some bleeding material separation phenomenon occurred, and in the case of Example 2, it can be seen that good results were shown in all test items.

In Example 3, the gelation time was delayed because the proportion of slaked lime in Agent A was low, and in Example 4, the proportion of calcium sulfuraluminate was decreased, so the gel time and initial strength were measured to be sharply and somewhat low.

In Example 5, as the amount of powder used decreased, the strength decreased and gel formation also slowed down. In Example 6, the strength was increased due to the high amount of powder used, but the gel time was faster. Meanwhile, due to the high amount of powder used, the bleeding prevention rate was almost the same even when the amount of bentonite used was reduced to half. In Example 7, when 0.5% citric acid, a curing retardant, was used in Example B, which was the standard mixing ratio, the gelation time increased from 12 seconds to 52 seconds.

On the other hand, in the case of Comparative Examples 1 and 2, in which liquid A cement milk liquid and liquid B sodium silicate solution were reacted according to the LW method, which has been generally the most widely adopted and used, shrinkage was very severe and long-term strength was weak during curing in air and water. can be seen.

In Comparative Example 3 where cement was not used, the shrinkage phenomenon was also relatively smaller than when cement was used, but it could be seen that it was not significantly improved due to the use of sodium silicate. In Comparative Example 4, shrinkage was significantly improved by using inorganic powder instead of sodium silicate as agent B, but the gel time was slow and long-term strength was weak.

Test example 2

(1) Whitening test

For the grout materials prepared in Example 2 and Comparative Examples 5 to 7 above, the specimen was cured for 7 days and then immersed in seawater for 3 days to form a white color due to the reaction of components in the specimen and components such as magnesium sulfate present in seawater. The degree of precipitation of precipitates was observed with the naked eye.

(2) Evaluation of chloride ion penetration resistance

For the grout materials prepared in Example 2 and Comparative Examples 5 to 7 above, chloride ion penetration resistance was evaluated according to the KS F2711 test method. After setting the test object in the center of the diffusion cell, using a 0.3M NaOH solution for the anode and a 3% NaCl solution for the cathode, a direct current voltage of 60V was applied to both ends of the cell for 6 hours, and the current flowing through the test object was measured. The total passing charge was measured.

(3) Test results

As a result, it was confirmed that while no significant phenomenon was observed in the samples of the grout materials prepared in Example 1 and Comparative Example 7, white precipitation was observed in the samples of the grout materials prepared in Comparative Examples 5 and 6.

In addition, the grout specimens prepared in Example 1, Comparative Example 5, and Comparative Example 6 were measured at a negligible background level, while the grout specimen prepared in Comparative Example 7 was measured at a considerably high level of about 279 coulombs. It was confirmed that the barrel and charge were measured.

Claims (10)

(a) Cement-free agent A containing 20-70% by weight of slaked lime and 30-80% by weight of desulfurized gypsum, and
(b) Non-silicate agent B containing 30-60% by weight of calcium sulfuraluminate, 35-67% by weight of slag fine powder, and 2-6% by weight of soda aluminate. Cement-free inorganic grout material. The method of claim 1, wherein either one of the agent A and the agent B or each includes bentonite having a swelling degree of 10 or more,
A non-silicate cement-free inorganic grout material comprising 3-4 kg of bentonite per 350 kg of agent A or agent B. (A) preparing solution A by adding agent A containing slaked lime and desulfurized gypsum to prepared water for solution A and dispersing it;
(B) preparing solution B by adding agent B containing calcium sulfuraluminate, fine slag powder, and sodium aluminate to prepared water for solution B and dispersing it; and
A grouting method comprising: (C) mixing the liquid A and the liquid B to form a grout material,
Use non-silicate cement-free inorganic grout material,
The agent A contains 20-70% by weight of slaked lime and 30-80% by weight of desulfurized gypsum,
A grouting method characterized in that the agent B contains 30-60% by weight of calcium sulfuraluminate, 35-67% by weight of slag fine powder, and 2-6% by weight of soda aluminate. delete According to paragraph 3,
100-600kg of agent A is added based on 500L of solution A,
A grouting method characterized in that 100-600 kg of Agent B is added based on 500L of Liquid B. According to clause 5,
The prepared water for solution A and the prepared water for solution B may have the same or different components, and are each independently water or water containing 3-40 kg of bentonite with a swelling degree of 10 or more per 500 L of solution A or per 500 L of solution B. A grouting method characterized by: According to clause 6,
A grouting method, characterized in that at least one of the prepared water for solution A and the prepared water for solution B is water containing 3-40 kg of bentonite with a swelling degree of 10 or more per 500 L of solution A or per 500 L of solution B. In clause 7,
A grouting method, characterized in that the prepared water for solution A and the prepared water for solution B each contain 3-40kg of bentonite with a swelling degree of 10 or more per 500L of solution A or 500L of solution B. According to any one of paragraphs 3 and 5 to 8,
The agent A additionally contains 0.1-10% by weight of citric acid based on the total weight of the slaked lime and the desulfurized gypsum, or
The agent B further contains 0.1-10% by weight of citric acid based on the total weight of the calcium sulfuraluminate and the slag fine powder, or
The agent A additionally contains 0.1-10% by weight of citric acid based on the total weight of the slaked lime and the desulfurized gypsum, and the agent B also contains 0.1-10% by weight of citric acid based on the total weight of the calcium sulfuraluminate and the slag fine powder. A grouting method characterized by additionally including weight percent. The grouting method according to claim 9, wherein the mixing volume ratio of the liquid A and the liquid B is 1:1.5 to 1.5:1.