KR102209772B1 - Gel time variable cement mineral eco-friendly grout composition - Google Patents

Abstract

The present invention relates to a grout composition for a cement mineral-based ground work, and the gel time of a liquid grout composition is simplified without being accompanied by significant fluctuations in basic properties of the grout composition such as leaching properties, strength and durability after hardening, etc. It is precisely controlled, suppresses material separation of the cement suspension, and secures the strength and corrosion resistance of the hardened injection material by utilizing industrial by-products.
Through the present invention that can easily control the gel time of the grout composition, it is possible to precisely control the penetration area in the ground of the grout composition, thereby securing the construction accuracy, preventing unnecessary material loss, and , It can prevent environmental pollution by inhibiting short-term material leaching.

Description

Cement mineral-based eco-friendly grout composition with easy gel time control {GEL TIME VARIABLE CEMENT MINERAL ECO-FRIENDLY GROUT COMPOSITION}

The present invention relates to a grout composition for a cement mineral-based ground work, and the gel time of a liquid grout composition is simplified without being accompanied by significant fluctuations in basic properties of the grout composition such as leaching properties, strength and durability after hardening, etc. It is precisely controlled, suppresses material separation of the cement suspension, and secures the strength and corrosion resistance of the hardened injection material by utilizing industrial by-products.

Grouting, also called a bishop, reinforces the ground or structure by inducing hardening by injecting liquid fillers such as bentonite, water glass, cement, asphalt, or various resin-based compounds into cracks in the ground or building. It is a technique that blocks the flow of groundwater.

In the construction industry, grouting is used in various fields such as reinforcing or reforming the foundation or the underlying ground of a structure, as well as suppressing groundwater outflow or artificially adjusting the groundwater level, depending on the purpose of construction, index grouting, ground improvement grouting, filling grouting, reinforcement It can be classified into grouting, etc., and can be classified into cavity grouting, crack grouting, void grouting, etc. according to the injection location of grout material.

As such, grouting can be classified in various ways depending on the purpose and object of application, but the basic mechanism is that the liquid injection material penetrates into the construction object and then hardens to express the desired strength. The main characteristic required for construction Examples thereof include fluidity before curing, curing speed, leaching property, strength and corrosion resistance after curing.

First of all, the fluidity before hardening is the fluidity as a liquid injection material, and if the fluidity is insufficient, it is difficult to smoothly penetrate through the gaps or joints between the earth particles in the ground of the liquid injection material, as well as the injection itself through the injection pipe. , A treatment such as imparting or improving fluidity is applied by adding a plasticizer or the like to the injection material.

The curing speed, that is, the rate at which the liquid injection material hardens and transforms into a gel or hardened material, which is a low-fluidity semi-liquid semi-solid, acts as a major factor in the expression of reinforcement and order effects as well as the setting of the construction area. In particular, due to the nature of the grouting construction, it is impossible to visually check the penetration, diffusion, and state change of the liquid injection material injected into the ground.The gel time, which is the time required for the liquid injection material to gel, is the injection material. It is used as a key factor in estimating the initial amount of loss and controlling penetration area.

In addition, properties such as leaching, strength, and corrosion resistance are characteristics that determine the physical properties and durability of the injection material during or after curing, and not only in coping with the influence of groundwater flow or salt water, but also in determining the reconstruction period. It is also considered an important factor.

As described above, in grouting construction, the grout material and injection method are determined by comprehensively considering the construction purpose, region, and required life, etc., as a grouting technique mainly used for reinforcement of soft ground and groundwater order. Grouting using a grout material may be mentioned, and Patent Publication No. 2000-71355 may be mentioned as a related prior art.

Conventional water glass grout materials, including Korean Patent Publication No. 2000-71355, are injected by mixing water glass chemical and cement milk, and due to excessive rapid reaction between silicate constituting water glass and calcium of cement, sufficient mixing between water glass chemical and cement milk In a state in which this is not achieved, there is a problem that supercharge hardening of some materials and leaching of residual materials are caused.

Accordingly, a grout material using synthetic resins such as urethane as a binder has been developed, but this also has a limitation in practical control of the material leaching phenomenon and has a serious problem that causes contamination of the surrounding groundwater.

The present invention was invented in view of the above-described problems, in a cement mineral grout composition, an inorganic chemical solution 40% to 60% by weight and a cement suspension 40% to 60% by weight are mixed simultaneously with injection into the ground, thereby forming a grout composition. However, the inorganic chemical liquid is composed of a mixture of 40% to 60% by weight of a powder formulation and 40% to 60% by weight of water, and the powder formulation is composed of calcium sulfoaluminate and calcium sulfoaluminate in the same amount. ) To 2 times the weight of calcium aluminate, an alkali metal carbonate of 0.8 to 1.5 times the weight of the calcium sulfoaluminate, an alkali metal aluminate of 0.2 to 0.4 times the weight of the alkali metal carbonate, and an alkali metal It is composed of a mixture of potassium hydroxide in the weight of 0.05 to 0.1 times the weight of the carbonate, and the cement suspension contains a cement, an admixture of 0.05 to 0.2 times the weight of the cement, and a retarder of 0.01 to 0.05 times the weight of the admixture. And, 1.5 to 3 times the weight of the cement is mixed and composed of water, the admixture is aluminum sulfate 1% to 10% by weight, anhydrite 30% to 40% by weight, calcium sulfoaluminate 10% to 10% by weight It is a cement mineral-based eco-friendly grout composition with easy gel time control, characterized in that 40% by weight and 20% to 40% by weight of functional by-products are mixed.

In addition, the functional by-product is a cement mineral-based eco-friendly grout composition with easy adjustment of gel time, characterized in that the functional by-product is a mixture of 60% to 80% by weight of fly ash and 20% to 40% by weight of bottom ash It is a cement mineral-based eco-friendly grout composition that is easy to control the gel time, characterized in that it is formed.

In addition, the alkali metal carbonate is a cement mineral-based eco-friendly grout composition with easy adjustment of gel time, characterized in that the alkali metal carbonate is calcium carbonate or magnesium carbonate, and the alkali metal aluminate is calcium aluminate or sodium aluminate. This is an easy cement mineral-based eco-friendly grout composition.

Through the present invention that can easily control the gel time of the grout composition, it is possible to precisely control the penetration area in the ground of the grout composition, thereby securing the construction accuracy, preventing unnecessary material loss, and , It can prevent environmental pollution by suppressing short-term material leaching.

In addition, by effectively suppressing the material separation of the cement suspension, the injection material is hardened to improve the strength and durability of the finished ground solidified body, and by applying industrial by-products, which have excellent corrosion resistance and are lightweight materials, as admixtures. , It is possible to obtain the effect of extending the life and reconstruction period of the underground solidified body.

1 is a graph of gel time variation according to the amount of retardant incorporated

The detailed configuration of the present invention will be described as follows.

The present invention is a two-component grout composition in which an inorganic chemical solution and a cement suspension are separately prepared, and then these inorganic chemical solutions and cement suspension are simultaneously injected into the ground to be constructed, and are mixed, wherein the inorganic chemical solution 40% to 60% by weight and the cement suspension 40 Wt% to 60% by weight are mixed at the same time as the final injection into the ground to constitute the grout composition.

The inorganic chemical solution of the present invention is composed of a powder formulation composed of calcium sulfoaluminate, calcium aluminate, alkali metal carbonate, alkali metal aluminate and potassium hydroxide, and water are mixed, and 40% to 60% by weight of a dry mixed powder formulation % And 40% to 60% by weight of water are mixed to form an inorganic chemical liquid.

Calcium Sulfo Aluminate and Calcium Aluminate in the powder formulation of the grout composition of the present invention form a complete hydration cured body when curing after injection of the grout composition of the present invention. Long-term leaching can be effectively suppressed, thereby preventing groundwater contamination due to leaching, as well as ensuring the durability and life of the completed underground solidified body.

In addition, calcium sulfoaluminate exerts an expansion effect and compensates for the shrinkage phenomenon that accompanies the curing, thereby achieving a tight filling of the grout composition in the ground. Calcium aluminate exhibits an excellent rapid setting effect and It promotes the hardening action and initial strength development of the grout composition.

Calcium carbonate or magnesium carbonate may be used as the alkali metal carbonate applied to the powder formulation of the grout composition of the present invention, and these alkali metal carbonates are a kind of filler, and do not cause side reactions, but the sealing properties of the grout injection material. ) Is secured.

In addition, as the alkali metal aluminate applied to the powder formulation of the present invention, calcium aluminate or sodium aluminate may be applied, and these alkali metal aluminates accelerate the hydration reaction of cement when mixed with a cement suspension to be described later. At the same time, it exhibits the effect of compensating the drying shrinkage of the cement by exerting its expandability, and the potassium hydroxide contained in the powder formulation of the present invention increases strength and exhibits rapid setting effects.

The powder formulation of the present invention is completed by pulverizing the individual materials as described above into a powder of 4,000 ㎠/g or more, and then kneading them at an appropriate mixing ratio, and the appropriate mixing ratio for each component constituting the powder formulation is as follows.

First, based on the weight of calcium sulfoaluminate in the powder formulation of the present invention, calcium aluminate is mixed in the same amount to twice the weight of calcium sulfoaluminate.

That is, per 1 kg of calcium sulfoaluminate, 1 kg to 2 kg of calcium aluminate is mixed, and when the amount of calcium aluminate is less than the range of the above mixing ratio, the rapid setting effect and strength expression are insufficient, and the amount of calcium aluminate is mixed. If the blending ratio exceeds the range, the workability and penetrating ability will be insufficient due to supercharged hardening.

The alkali metal carbonate to which calcium carbonate or magnesium carbonate is applied is mixed in a weight ratio of 0.8 to 1.5 times the weight of calcium sulfoaluminate, that is, 0.8 kg to 1.5 kg of alkali metal carbonate per 1 kg of calcium sulfoaluminate. When the mixing amount of carbonate is less than the above range, the filling of the micropores in the finished solidified body is insufficiently performed, and when the mixing amount of alkali metal carbonate exceeds the range of the above mixing ratio, physical properties such as tissue relaxation and strength due to overfilling are reduced. Is caused.

Alkali metal aluminate to which calcium aluminate or sodium aluminate is applied is mixed with a weight ratio of 0.2 to 0.4 times the weight of the alkali metal carbonate, that is, 0.2 kg to 0.4 kg of alkali metal aluminate per 1 kg of alkali metal carbonate. However, when the mixing amount of alkali metal aluminate is less than the range of the above mixing ratio, when it is mixed with the cement suspension to be described later, the cement hydration reaction is sluggish and the formation of cavities in the solidified body due to drying shrinkage of the cement is caused. When the amount of the foate salt exceeds the range of the blending ratio, workability and penetrability decrease due to excessive expansion.

In addition, potassium hydroxide is mixed as a trace additive of the powder formulation of the present invention. Potassium hydroxide is a weight ratio of 0.05 to 0.1 times the weight of the alkali metal carbonate, that is, 0.05 kg to 0.1 kg of potassium hydroxide per 1 kg of alkali metal carbonate. Mixing is preferable for increasing the strength and securing the rapid setting effect.

The powder formulation to be mixed at the mixing ratio as described above is homogeneously mixed in a dry bibim format, and then water is mixed and stirred immediately before use in the field to complete an inorganic chemical solution.

On the other hand, the cement suspension constituting the grout composition of the present invention is composed of a mixture of cement and water, as in the dictionary meaning, and a small amount of admixture and retarder may be added to the cement, and these admixtures and retarders are cement It is homogeneously mixed with the cement in dry mixing form prior to mixing the cement and water to form the suspension.

However, since the amount of the retarder is changed depending on the planned penetration capacity and site conditions, the retardant is mixed in the final step, that is, the mixing step of the blended water to form the cement suspension, or once cement, After forming a cement suspension by mixing an admixture and water, a method of adding a retarder to the cement suspension may be applied.

In mixing cement and water to form a cement suspension, it is preferable to mix water with a weight of 1.5 to 3 times the weight of cement excluding admixtures and retardants, and thus a cement suspension with sufficient fluidity and penetrability is provided. Can be.

As the cement constituting the cement suspension, conventional cement such as Portland cement can be applied, and the admixture to be mixed with the cement is preferably mixed in a ratio of 0.05 to 0.2 times the weight of the cement, and the retarder. Is preferably mixed at a weight ratio of 0.01 to 0.05 times the weight of the admixture, that is, at a ratio of 0.01 kg to 0.05 kg of retardant per 1 kg of admixture.

The admixture to be mixed with cement when preparing the cement suspension of the present invention is composed of aluminum sulfate, anhydrous gypsum, calcium sulfoaluminate, and powdery functional by-products.

Among the constituents of the admixture, aluminum sulfate and anhydrous gypsum play a role in accelerating the hydration reaction of cement.In particular, anhydrite is in the cement suspension by fixing temporary excess water that is inevitably formed in the cement suspension. It plays the role of suppressing material separation.

In the cement-applied grout injection material including the present invention, a cement suspension is mixed with a superior amount of water compared to other mortar or concrete in order to secure fluidity and penetrating ability.After being injected into the ground to be constructed, it is sufficiently mixed with inorganic chemicals. If this is not done, a bleeding phenomenon in which the cement in the cement suspension is separated from water is caused, and in the end, the solidified body in the ground is insufficiently formed or the strength of the solidified body is deteriorated.

Accordingly, in the present invention, by adding anhydrous gypsum or the like to the admixture constituting the cement suspension rather than the inorganic chemical solution as described above, material separation of the cement suspension is suppressed, and the strength and tightness of the finished solidified body are secured.

Calcium sulfoaluminate mixed in the admixture also temporarily fixes excess water in the cement suspension in the same context as the action of the aluminum sulfate and anhydrous gypsum, accelerates the hydration reaction of the cement, and at the same time has a hardening action upon final mixing with the inorganic chemical solution. It performs the function of reinforcing and promoting, and it is also mixed with the admixture constituting the cement suspension as well as the powder preparation constituting the inorganic chemical solution.

That is, in the grout composition of the present invention, anhydrous gypsum and calcium sulfoaluminate are not contained in the inorganic chemical solution, but are contained in the cement suspension, or both are contained in the inorganic chemical solution and the cement suspension, thereby ensuring smooth reaction characteristics. In addition, defects such as material separation before curing can be effectively suppressed.

However, by premixing the above-described hardening or hardening accelerating material to the cement suspension, unnecessary preceding reactions may proceed, but the admixture of the present invention is prepared in a state of dry mixing with cement to maintain a state in which all reactions are suppressed. , As the cement suspension is finally formed by mixing with water at the site immediately before being injected into the ground to be constructed, stable work is possible without excessive preceding reactions.

The functional by-products mixed with the admixture of the cement suspension of the present invention are industrial by-products in the form of fine powders such as power generation by-products, and first, fly ash may be applied, and fly ash and other industrial by-products may be mixed as well as fly ash alone. May be.

Fly ash can provide light weight and improved corrosion resistance to the finished solidified body based on excellent dispersibility and corrosion resistance.

On the other hand, when fly ash and other industrial by-products are mixed, the functional by-product containing fly ash is composed of a mixture of fly ash and bottom ash, thereby reducing the weight, corrosion resistance, and dispersibility. While taking full advantage of the inherent advantages of ash, it is possible to achieve an advantageous synergistic effect exhibited by the combination of these fly ash and bottom ash.

Fly ash and bottom ash are industrial by-products generated from coal combustion and are mainly generated in facilities that consume a large amount of coal such as thermal power plants, and both share the characteristics of lightweight materials resulting from the commonality of residues after combustion. The difference is that fly ash is collected from the exhaust gas and bottom ash is collected from the downfall.

In the case of fly ash, it is widely applied as a cement admixture based on its excellent weight reduction and corrosion resistance effect, and is mainly used for lightweight concrete and concrete for preventing salt damage, but bottom ash is not highly utilized than fly ash, and some concrete It is used as an aggregate in products.

This is derived from the recognition that bottom ash is disadvantageous compared to fly ash in terms of weight reduction and corrosion resistance. For this reason, although it is a by-product generated by burning the same fuel in the same facility, bottom ash is not applicable as a cement admixture unlike fly ash. It was sluggish.

However, by mixing fly ash and bottom ash into an admixture as a functional by-product, each of the advantages can be fully utilized and the disadvantages can be compensated.

Corrosion resistance and dispersibility, which are the advantages of fly ash, are largely due to the powdery particle structure.Fly ash is atomized in the process of burning coal at a high temperature, and the surface is partially melted to have a rich spherical particle structure. While excellent corrosion resistance is formed, dispersibility is imparted based on fluidity in the liquid.

In particular, the good dispersibility and fluidity of fly ash can increase the workability by doubling the fluidity of the blended cement concrete, thereby reducing the number of blending water, and eventually improving the strength of the finished concrete. This may be effective for general cement concrete, but as described above, a practical effect cannot be expected in a grout injection material to which a compounding water that exceeds the amount of mixing water in a conventional concrete is applied.

In other words, in general concrete in which a relatively small amount of water is mixed, the fluidity of the concrete before hardening is improved through the dispersibility of fly ash, and as a result, the required mixing quantity is reduced, thus improving the long-term strength, but a large amount of In the grout injection material to which the compounding water is applied, the dispersibility of fly ash may cause excessive fluidity and material separation, and may cause side effects of reducing initial strength.

The side effects of fly ash as an admixture can be confirmed through the fact that the effect of fly ash as an admixture is focused on long-term strength rather than short-term strength.In the prior art, the effects of fly ash are overlooked and effects in general concrete. It is a situation that follows a simple method of mixing fly ash alone as a cement suspension admixture for grout injection material with blind faith.

Accordingly, in the present invention, fly ash and bottom ash are mixed to maintain the effect of improving corrosion resistance and long-term strength while compensating or supplementing the characteristics of the particle structure of the fly ash, and applied to the admixture as a functional by-product. Not only the material is the same, but the generation process is the same, so that unnecessary overreaction and side reaction are not caused at all, and a high degree of stability can be ensured.

As described above, bottom ash is collected as a falling material and has a relatively large particle diameter compared to fly ash, and unlike fly ash in which fine spherical particles are formed, it has an irregular particle shape such as a plate or flake. When mixing, the formation of excessive fluidity and dispersibility is suppressed, and at the same time, a tight and solid bond structure with other granular bodies constituting the cement suspension is established.

In addition, as described above, since fly ash and bottom ash are by-products generated in the same facility, convenience of supply and demand can also be easily secured.

However, since bottom ash is collected as coarse-grained granules, unlike fly ash, which is collected in the form of fine powder, it needs to be pulverized into fine powder before mixing with fly ash in order to constitute a functional by-product mixed with the admixture. have.

The powdery material constituting the cement suspension of the present invention, that is, the admixture and the retarder are both mixed in a fine powder form to ensure reactivity, and as in the powder formulation of the inorganic chemical liquid described above, the admixture and retarder material of the cement suspension are also individually After the material is pulverized into a powder of 4,000㎠/g or more, it is mixed with an appropriate mixing ratio.

The mixing ratio of the admixture applied to the cement suspension of the present invention is from 1% to 10% by weight of aluminum sulfate, from 30% to 40% by weight of anhydrite, from 10% to 40% by weight of calcium sulfoaluminate, from 20% by weight to functional by-products. It is preferable that 40% by weight is mixed to form an admixture.

Here, when aluminum sulfate, anhydrous gypsum, and calcium sulfoaluminate are mixed in the admixture below the above mixing ratio, a sufficient curing acceleration and expansion effect cannot be expected, as well as in compensating for the shrinkage of the finished solidified body and preventing material separation. Effects cannot be expected, and when aluminum sulfate, anhydrous gypsum, and calcium sulfoaluminate are mixed in excess of the above mixing ratio, the workability is deteriorated due to supercharged hardening and excessive expansion, and the penetrating ability decreases.

Functional by-products, too, cannot be expected to significantly improve corrosion resistance, reduce weight, and prevent material separation when mixed with an admixture below the above mixing ratio, and when mixed in excess of the above mixing ratio, it causes a relative shortage of the amount of cement, resulting in a decrease in long-term and short-term strength. Can cause.

In addition, the fly ash and bottom ash constituting the functional by-products in the cement suspension admixture of the present invention are preferably composed of a mixture of 60% to 80% by weight of fly ash and 20% to 40% by weight of bottom ash. In order to control excessive dispersibility by adding an appropriate amount of bottom ash while maintaining the superiority of fly ash in by-products to the maximum, such as corrosion resistance and light weight, bottom ash less than the mixing ratio is When added, a significant dispersibility control effect cannot be expected, and when bottom ash exceeding the mixing ratio is added, the light weight and fluidity peculiar to fly ash may be impaired.

On the other hand, when preparing the cement suspension of the present invention, the retarding agent mixed with cement and admixture is to delay coagulation to ensure the fluidity and penetration ability of the injection material during grouting, and powdery citric acid or powdery tartaric acid is applied, and the grout injection material The mixing amount will be increased or decreased in consideration of the site conditions such as the planned penetration range and the water temperature of the mixed water.

That is, as the mixing amount of the retarding agent such as citric acid added to the cement suspension is increased, the gel time of the grout composition is delayed.As described above, in the present invention, in the present invention, it accelerates hardening and fixation of excess water, such as anhydrite and calcium sulfoaluminate. Although the functional material is mixed with citric acid in the cement suspension, the interaction of anhydrous gypsum and calcium sulfoaluminate inhibiting unnecessary overreaction and side reaction, and the content in the admixture of these anhydride gypsum and calcium sulfoaluminate are at an appropriate level. By setting and managing, not only can the delaying effect of setting by the retarding agent be maintained, but also the tendency of the gel time delaying effect to follow the mixing amount of the retarding agent can be firmly maintained.

The mixing ratio of the retarder may be applied within the range of 1% to 5% by weight of the weight of the admixture described above, and the gel time is shortened as the mixing amount of the retarder decreases, thereby imparting purity to the grout injection material. As the amount of mixing increases, the gel time is prolonged, thereby imparting completeness to the grout injection material.

In the following examples, the variation of the gel time was measured by stepwise changing the mixing amount of the retarder in a section ranging from 1% to 5% by weight of the admixture weight, thereby measuring the variation of the coagulation material as described above. In spite of the characteristic configuration of the present invention, such as application of admixtures for cement suspension, application of fly ash and bottom ash complex functional by-products, it is confirmed that the delay effect of the gel time follows the mixing amount of the retarder.

The tendency of the gel time delay effect according to the mixing amount of the retarder is a very important characteristic in actual field application of the grout injection material composition, and through this, it is possible to estimate the initial loss amount of the injection material and control the penetration area.

Powder preparation of inorganic chemicals

1,000g of calcium sulfoaluminate crushed to 4,000 ㎠/g powder, 1,500g of calcium aluminate crushed to 4,000 ㎠/g powder, 1,000kg of calcium carbonate crushed to 4,000 ㎠/g, 4,000 ㎠/ 300 kg of calcium aluminate pulverized to g and 80 g of potassium hydroxide crushed to 4,000 cm2/g were dry and homogeneously mixed to prepare a powder formulation of 3,880 g.

Admixture preparation

50 g of fly ash and 20 g of bottom ash pulverized at 4,000 ㎠/g were dry and homogeneously mixed to prepare 70 g of functional by-products.

Then, 10 g of aluminum sulfate, 70 g of anhydrous gypsum, 50 g of calcium sulfoaluminate, and 70 g of the functional by-product were dry and homogeneously mixed to prepare 200 g of admixture.

Composition of inorganic chemicals

2,000 g of the powder formulation and 2,000 g of water at 20° C. are stirred and mixed to form 4,000 g of an inorganic chemical solution.

Cement suspension composition

First, 200 g of Portland cement, 30 g of the admixture, 0.3 g of citric acid, and 400 g of water at 20° C. are stirred and mixed to form 630.3 g of Type 1 cement suspension.

Further, 200 g of Portland cement, 30 g of the admixture, 0.6 g of citric acid, and 400 g of water at 20° C. were stirred and mixed to form 630.6 g of Type 2 cement suspension.

In addition, 200 g of Portland cement, 30 g of the admixture, 0.9 g of citric acid, and 400 g of water at 20° C. were stirred and mixed to form 630.9 g of Type 3 cement suspension.

Further, 200 g of Portland cement, 30 g of the admixture, 1.2 g of citric acid, and 400 g of water at 20° C. were stirred and mixed to form 631.2 g of Type 4 cement suspension.

Further, 200 g of Portland cement, 30 g of the admixture, 1.5 g of citric acid, and 400 g of water at 20° C. were stirred and mixed to form 631.5 g of Type 5 cement suspension.

Formation of grout composition and measurement of gel time

After loading 100 g of the inorganic chemical liquid and 100 g of the type 1 cement suspension into separate containers, the inorganic chemical liquid or the type 1 cement suspension loaded in one container is added to the other container and mixed, and time measurement is started. , The time measurement is continued by repeatedly moving the mixture of inorganic chemicals and cement suspension from one container to the other, and when the fluidity of the inorganic chemical and cement suspension mixture is lost and the immediate movement between containers stops, the time measurement is stopped. And measuring the time elapsed for the cement suspension mixture to gel.

This process was carried out as a mixture of 100 g of inorganic chemicals and 100 g of type 2 cement suspension, 100 g of inorganic chemicals and 100 g of type 3 cement suspension, 100 g of inorganic chemicals and 100 g of type 4 cement suspension, and 100 g of inorganic chemicals and 100 g of type 5 cement suspension. Do the same for

The gel time measurement for the type 1 to type 5 cement suspensions was performed five times for each cement suspension to calculate an average value, and the results are shown in Table 1 below and the accompanying FIG. 1.

Gel time change according to the amount of citric acid mixed division Citric acid addition amount compared to admixture Gel time (seconds) Type 1 cement suspension 1% by weight 8±03 Type 2 cement suspension 2% by weight 15±04 Type 3 cement suspension 3% by weight 27±09 Type 4 cement suspension 4% by weight 57±12 Type 5 cement suspension 5% by weight 112±21

As can be seen from Table 1 and the accompanying FIG. 1, it can be seen that the gel time of the grout composition of the present invention follows the amount of citric acid as a retarder.

In addition, as described above, in the present invention, it can be seen that not only is a settable material added to the admixture for a cement suspension, but also precise and stable control of the gel time is possible despite the complex application of various industrial by-products.

Claims (1)

In the two-component cement mineral grout composition in which the inorganic chemical solution and the cement suspension are separately prepared, and then the inorganic chemical solution and the cement suspension are simultaneously injected into the ground to be constructed and mixed,
40% to 60% by weight of the inorganic chemical solution and 40% to 60% by weight of the cement suspension are mixed simultaneously with injection into the ground to form a grout composition,
The inorganic chemical liquid is composed of a mixture of 40% to 60% by weight of a powder formulation and 40% to 60% by weight of water;
The powder formulations include calcium sulfoaluminate, calcium aluminate in the same amount as calcium sulfoaluminate, and magnesium carbonate in the weight of 0.8 to 1.5 times the weight of calcium sulfoaluminate, and magnesium carbonate 0.2 to 0.4 times the weight of sodium aluminate and 0.05 to 0.1 times the weight of potassium hydroxide are mixed.
The cement suspension is composed of cement, an admixture of 0.05 to 0.2 times the weight of cement, citric acid of 0.01 to 0.05 times the weight of the admixture, and water of 1.5 to 3 times the weight of cement;
The admixture is a mixture of 1% to 10% by weight of aluminum sulfate, 30% to 40% by weight of anhydrous gypsum, 10% to 40% by weight of calcium sulfoaluminate, and 20% to 40% by weight of fly ash. Cement mineral-based eco-friendly grout composition with easy control of gel time.

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