CN110818328A - Geopolymer grouting material, preparation method thereof and application thereof in reinforcing village and town construction foundation - Google Patents

Abstract

The invention relates to a geopolymer grouting material, a preparation method thereof, and its application in the reinforcement of village construction foundations. The geopolymer grouting material, by weight percentage, comprises the following components: steel slag: 55.0-65.0%; slag: 5.0-10.0%; copper slag: 10.0-15.0%; carbide slag: 5.0-8.0%; industrial salt: 3.0 to 5.0%; waste gypsum: 5.0 to 10.0%; fluid stability modification material: 2.0 to 3.0%. The geopolymer grouting material of the present invention has wide raw material sources and low price, makes full use of various types of wastes to construct a gelling system, and has significant social and environmental benefits. Stable construction performance, good pourability, reaction with soil, early strength and fast hardening, good foundation bearing capacity and volume stability, especially suitable for the reinforcement of village construction foundations.

Description

Geopolymer grouting material and its preparation method and its use in village construction foundation reinforcement Applications

technical field

The present invention relates to the field of building materials, in particular to a geopolymer grouting material and its preparation method and its application in the reinforcement of village and town construction foundations.

Background technique

In recent years, my country's economy has been developing steadily and rapidly, and the urbanization process has been accelerated. Under such a background, the economic and social system in rural areas has obtained more convenient development opportunities, the market of village and town buildings has also become active, and the scale of village and town buildings has become larger and larger. At the same time, the safety problem of buildings in villages and towns also appears, because the problem of insufficient bearing capacity of foundations generally exists in villages and towns in my country, and the damage to buildings and infrastructure in villages and towns often occurs. Urban construction is usually reinforced by grouting, and the main cementing material is cement, which is expensive and not suitable for large-scale use in village and town construction. In addition, the current grouting material still has problems such as unstable performance and low early strength.

Based on the above background, a kind of reinforcement grouting material with low price, stable performance and early strength is urgently needed in the construction of villages and towns.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a geopolymer grouting material and its preparation method and its application in the reinforcement of village and town construction foundations. The soil has the characteristics of good adaptability, early strength and fast hardening, and slight expansion, which is suitable for the reinforcement of village and town construction foundations.

The purpose of the present invention and the solution to its technical problems are achieved by adopting the following technical solutions. According to a geopolymer grouting material proposed by the present invention, in weight percent, it comprises the following components:

Steel slag: 55.0～65.0%;

Slag: 5.0～10.0%;

Copper slag: 10.0～15.0%;

Carbide slag: 5.0～8.0%;

Industrial salt: 3.0～5.0%;

Waste gypsum: 5.0 to 10.0%;

Fluid stability modification material: 2.0 to 3.0%.

The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

Preferably, the aforementioned geopolymer grouting material, wherein the fluid state stability modification material, in terms of weight percentage, comprises the following components:

Bentonite: 54.0～66.0%;

Powdered water reducing agent: 22.0～28.0%;

Aluminum slag: 8.0～12.0%;

Defoamer: 4.0 to 6.0%.

Preferably, in the aforementioned geopolymer grouting material, wherein the powdery water-reducing agent is a powdery early-strength polycarboxylic acid-based high-performance water-reducing agent, which contains 6.0-8.0wt% of nano-CSH nucleating agent, Its water reduction rate is greater than 30%, the 28-day shrinkage ratio is less than 70%, and the 1-day compressive strength ratio is greater than or equal to 200%.

Preferably, the aforementioned geopolymer grouting material, wherein the bentonite is ground bentonite ore powder, its montmorillonite content is greater than 60%, and the fineness is 200 mesh;

Described aluminum slag is aluminum slag micropowder, and its Blaine specific surface area is 200±20m ² /kg;

The defoamer is powder defoamer, which is prepared by adsorbing mineral oil and nonionic surfactant on an inert carrier.

Preferably, in the aforementioned geopolymer grouting material, the steel slag is steel slag micropowder, its basicity is ≥2.4, the weight ratio of free calcium oxide is ≥6.0%, the weight ratio of free magnesium oxide is 5.0-8.0%, The specific surface area is 800±20m ² /kg;

The slag is granulated blast furnace slag powder, the basicity coefficient is greater than 1.2, the quality coefficient is greater than 1.4, the specific surface area of Blaine is 600±20m ² /kg, the water demand is less than 90%, and the 28d activity index is greater than 110%;

The copper slag is copper slag micropowder, its glass body content is more than 15%, and the Blaine specific surface area is 450±20m ² /kg.

Preferably, in the aforementioned geopolymer grouting material, the calcium carbide slag is calcium carbide slag micropowder, the calcium hydroxide content is greater than 85%, and the Brinell specific surface area is 400±20 m ² /kg;

Described industrial salt is sun-dried industrial salt, and its sodium chloride content is greater than 96%;

The waste gypsum is ground waste gypsum mold powder, the content of sulfur trioxide is more than 46.0%, and the specific surface area of Brinell is 400±20 m ² /kg.

The purpose of the present invention and the solution to its technical problems are also achieved by the following technical solutions. According to the preparation method of a geopolymer grouting material proposed by the present invention, it comprises:

The components in the geopolymer grout described in any one of the preceding items are mixed uniformly.

The purpose of the present invention and the solution to its technical problems are also achieved by the following technical solutions. According to the application of the geopolymer grouting material described in any one of the above mentioned in the present invention in the reinforcement of the construction of villages and towns.

The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

Preferably, in the aforementioned application, the geopolymer grouting material is mixed uniformly, and can be poured after adding water and stirring to make the slurry.

Preferably, in the aforementioned application, the weight of the water is 25.0-30.0% of the geopolymer grouting material; the stirring speed is 10-14 m/s, and the stirring time is 3-5 min.

By the above-mentioned technical scheme, the geopolymer grouting material of the present invention and its preparation method and its application in village and town construction foundation reinforcement have at least the following advantages:

1. The present invention utilizes the step hydration characteristics of free calcium oxide (f-CaO) and free magnesium oxide (f-MgO) in the ultra-fine steel slag micropowder to make its swellable products Ca(OH) ₂ and Mg(OH) ) ₂ The formation rate matches the strength growth and volume change of the geopolymer grouting material, establishes an effective micro-expansion under the action of constraints, compensates for the shrinkage, and increases the friction between the solidified body of the geopolymer grouting material and the soil, thereby improving the foundation. Bearing capacity and volume stability. In addition, the generated Ca(OH) ₂ can also stimulate the active SiO ₂ and Al ₂ O ₃ in itself and other waste residues to generate CSH gel, which further increases the strength of the grout matrix and promotes early strength and fast hardening.

2. The function of using the fluid-state stable modification material in the present invention is to increase the rheological property of the geopolymer grouting material, improve its filling ability, and reduce the sensitivity to the fluctuation of water consumption, thereby improving the bearing capacity of the foundation.

3. In the present invention, calcium carbide slag, industrial salt and waste gypsum are used to activate the steel slag-slag-copper slag composite cementation system to increase calcification and alkali excitation and salt excitation to fully stimulate the activity of the system itself and the reaction with the soil, and improve the geopolymer. On the basis of the strength of the grouting material itself, it also helps to increase the bearing capacity and stability of the foundation.

4. The rheologically stable modified material prepared by using bentonite, powdery water reducing agent, aluminum slag and defoamer in the present invention can significantly improve the rheology and thixotropy of the geopolymer grouting material, and the introduced tiny bubbles reduce frictional force , to improve its perfusion and compactness. At the same time, reducing the sensitivity to fluctuations in water consumption helps to increase the bearing capacity of the foundation.

5. The geopolymer grouting material of the present invention has a wide range of raw material sources, low price, and makes full use of various types of waste to build a gelling system, which has significant social and environmental benefits. It has stable construction performance, good pourability, reacts with soil, has early strength and fast hardening, and has good foundation bearing capacity and volume stability, especially suitable for the reinforcement of villages and towns.

The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly, and to implement it according to the content of the description, the preferred embodiments of the present invention are described in detail below.

Detailed ways

In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the following in conjunction with preferred embodiments, the geopolymer grouting material proposed according to the present invention and its preparation method and its application in the reinforcement of village and town construction foundations The specific implementation and its efficacy are described in detail as follows. In the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

The embodiment of the present invention provides a geopolymer grouting material, which comprises the following components in weight percentage: steel slag: 55.0-65.0%; slag: 5.0-10.0%; copper slag: 10.0-15.0%; carbide slag: 5.0 ～8.0%; Industrial salt: 3.0～5.0%; Waste gypsum: 5.0～10.0%; Fluid stability modification material: 2.0～3.0%.

In the embodiment of the present invention, the geopolymer is a polymer with a three-dimensional cross-linked aluminum silicate structure composed of Si-O-Al-O bonds, and the structure of the geopolymer can be amorphous or semi-crystalline, belonging to non-metallic Material. This material has excellent mechanical properties, acid and alkali resistance, fire resistance and high temperature resistance. It is possible to replace ordinary Portland cement and can use mineral waste and construction waste as raw materials.

Preferably, the steel slag is steel slag micropowder, which is obtained by grinding and shaping the steel slag treated by the air quenching method through a vertical mill-ball mill combined grinding system. The particles are spherical and have good particle gradation. The basicity of the steel slag micropowder is ≥2.4, the weight ratio of free calcium oxide (f-CaO) is ≥6.0%, the weight ratio of free magnesium oxide (f-MgO) is 5.0～8.0%, and the Blaine specific surface area is 800±20m ² / kg. The steel slag micropowder makes the geopolymer grouting material have the characteristics of micro-expansion, high bearing capacity and fast hardening and early strength.

In the technical scheme of the present invention, the steel slag is first processed by the air quenching method, and then pulverized and shaped by the vertical mill-ball mill combined grinding system to obtain the steel slag micropowder; the particles of the steel slag micropowder are spherical and have good particle gradation. Steel slag is ground to a certain fineness to become steel slag micropowder, which has significant economic, environmental and social benefits, conforms to national industrial policies, and has a broad market.

Basicity is the ratio of the mass sum of calcium oxide and magnesium oxide in the steel slag micropowder to the mass sum of silicon dioxide and aluminum oxide.

The steel slag used in the embodiment of the present invention is steel slag micropowder. On the one hand, free calcium oxide (f-CaO) and free magnesium oxide (f-MgO) in the steel slag micropowder are hydrated in stages, and expansive products are formed successively. Ca(OH) ₂ and Mg(OH) ₂ match with the strength growth and volume change of the geopolymer grouting material, establish effective expansion under restraint, compensate for shrinkage, and increase the bond between the solidified body of the geopolymer grouting material and the soil. Friction, thereby improving the bearing capacity of the foundation and increasing the stability. On the other hand, the C ₂ S and C ₃ S silicate minerals in the steel slag micropowder can be hydrated by themselves to produce gelation, which accelerates the strength growth of the geopolymer grouting material. In addition, the expansive product Ca(OH) ₂ can stimulate the active SiO ₂ and Al ₂ O ₃ in the steel slag micropowder and other industrial wastes to generate CSH gel, which further increases the matrix strength of the geopolymer grouting material.

Preferably, the slag is granulated blast furnace slag powder, its basicity coefficient (M ₀ ) is greater than 1.2, the quality coefficient is greater than 1.4, the specific surface area of Brinell is 600±20m ² /kg, the water demand is less than 90%, and the 28d activity is The index is greater than 110%.

The basic coefficient (M ₀ ) is the ratio of the mass sum of calcium oxide and magnesium oxide in the slag micropowder to the mass sum of silicon dioxide and aluminum oxide.

The quality factor is the ratio of the mass sum of calcium oxide, aluminum oxide and magnesium oxide to the mass sum of silicon dioxide, manganese monoxide and titanium dioxide in the granulated blast furnace slag powder.

The 28d activity index was obtained according to the following steps: according to the test method GB/T17671, the compressive strength of the test sample for 28 days was measured, and it was counted as R ₂₈ (MPa); the compressive strength of the comparative sample for 28 days was counted as R ₀₂₈ (MPa) ; Calculate its 28d activity index A ₂₈ (%) according to the formula A ₂₈ =R ₂₈ ÷ R ₀₂₈ ×100 (%), and the calculation result is rounded to an integer.

Preferably, the copper slag is copper slag micropowder, the content of glass body is more than 15%, and the specific surface area of the copper slag is 450±20 m ² /kg.

The main function of copper slag micropowder is to control the fluidity of geopolymer grouting material.

Preferably, the calcium carbide slag is calcium carbide slag micropowder, the calcium hydroxide content is more than 85%, and the Brinell specific surface area is 400±20 m ² /kg.

The main function of carbide slag micropowder is to increase the calcium content of the geopolymer grouting material, and the alkali stimulates SiO ₂ and Al ₂ O ₃ in other waste residues, so that the geopolymer grouting material has the characteristics of early strength and fast hardening.

Preferably, the industrial salt is sun-dried industrial salt, and its sodium chloride content is greater than 96%. Its main function is that high salt stimulates the activity of other industrial waste residues, so that the geopolymer grouting material has the characteristics of early strength and fast hardening.

Preferably, the waste gypsum is ground waste gypsum mold powder, the content of sulfur trioxide is more than 46.0%, and the specific surface area of Brinell is 400±20 m ² /kg.

Preferably, the fluid state stability modification material, in terms of weight percentage, comprises the following components: bentonite: 54.0-66.0%; powdery water reducing agent: 22.0-28.0%; aluminum slag: 8.0-12.0%; Defoamer: 4.0 to 6.0%. More preferably, bentonite: 60.0%; powdery water reducing agent: 25.0%; aluminum slag: 10.0%; defoaming agent: 5.0%.

The function of the fluid stability modifier is to increase the rheology of the geopolymer grouting material, improve its fillability, and reduce the sensitivity to fluctuations in water consumption, thereby improving the bearing capacity of the foundation.

Further preferably, the powdery water-reducing agent is a powdery early-strength polycarboxylic acid-based high-performance water-reducing agent, which contains 6.0-8.0wt% of nano-CSH nucleating agent, and its water-reducing rate is greater than 30%, 28 The day shrinkage ratio is less than 70%, and the 1 day compressive strength ratio is ≥200%.

The powdery water-reducing agent is more preferably a shrinkage-early-strength composite polycarboxylic acid-based water-reducing agent.

Further preferably, the bentonite is ground bentonite ore powder, the content of montmorillonite is more than 60%, and the fineness is 200 mesh. The role of bentonite is to adjust the rheological properties of the geopolymer grouting material and to play a dispersing role at the same time.

Further preferably, the aluminum slag is aluminum slag micropowder, and its Blaines specific surface area is 200±20 m ² /kg. Its function is to introduce tiny air bubbles to improve the fluidity and stability of geopolymer grouting.

Further preferably, the defoamer is a powder defoamer, which is prepared by adsorbing mineral oil and nonionic surfactant on an inert carrier.

An embodiment of the present invention also proposes a method for preparing a geopolymer grouting material, which includes the following steps: weighing raw materials according to the aforementioned components and proportions in the geopolymer grouting material, and mixing them evenly to obtain a geopolymer grouting material material, which is a dry blend composition.

The embodiment of the present invention also proposes an application of the aforementioned geopolymer grouting material in the reinforcement of village construction foundations.

Preferably, water is added to the geopolymer grouting material, and the slurry can be poured after stirring.

Preferably, the weight of the water is 25.0-30.0% of the geopolymer grouting material, more preferably 27.0%; the stirring speed is 10-14 m/s, more preferably 12 m/s, and the stirring time 3 to 5 minutes, more preferably 4 minutes.

The present invention will be further described below in conjunction with specific embodiments, but it should not be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art according to the above-mentioned content of the present invention still belong to the present invention. the scope of protection of the invention.

Examples 1 to 5

For the geopolymer grouting materials of Examples 1 to 5, each component was weighed according to the formula shown in Table 1 and Table 2, various raw materials were mixed uniformly, and added to a high-speed mixer together with water, wherein the weight of the added water accounted for 27.0% of the dry-mixed composition of the geopolymer grouting material, the linear speed of the stirring blade is 12 m/s, and the rapid stirring is carried out for 4 minutes to obtain a geopolymer grouting slurry with high fluidity, early strength, fast hardness and slight expansion.

According to SZ-G-B04-2007 "Technical Regulations for the Reinforcement of Geopolymer Grouting of Highway Subgrade and Base Layer", the performance test of the grouting grouting prepared in each example was carried out, and its initial fluidity, bleeding rate, swelling rate, Water resistance, 1d compressive strength, 7d compressive strength, 28d compressive strength and other performance tests, the test results are shown in Table 3.

Formulation of geopolymer grouting material in each example in Table 1 (% by weight)

steel slag slag copper slag Carbide slag industrial salt waste gypsum Fluid Stability Modifiers Example 1 55.0 10.0 15.0 5.0 3.0 10.0 2.0 Example 2 58.0 8.0 13.0 7.0 3.5 8.0 2.5 Example 3 60.0 5.0 12.0 8.0 4.5 7.5 3.0 Example 4 62.0 7.0 13.0 6.0 4.0 5.0 3.0 Example 5 65.0 5.0 10.0 8.0 5.0 5.0 2.0

The formula (mass percentage content %) of the fluid state stability modification material added in each embodiment of table 2

bentonite Powdered water reducer Aluminum slag defoamer Example 1 60.0 25.0 9.0 6.0 Example 2 58.0 27.0 10.5 4.5 Example 3 60.0 27.5 8.5 4.0 Example 4 54.0 28.0 12.0 6.0 Example 5 66.0 22.0 8.0 4.0

Table 3 Performance data table of the grouting slurry prepared in each example

It can be seen from Table 3 that the grouting slurries prepared in Examples 1 to 5 have an initial fluidity of 14.5 to 16.2 s, a bleeding rate of 0, an expansion rate of 0.05 to 0.07%, and a water resistance of 104.0 to 110.0 %, the 1d compressive strength is between 23.2 and 27.8MPa, the 7d compressive strength is between 34.8 and 39.6MPa, and the 28d compressive strength is between 42.4 and 47.4MPa. Compared with the common geopolymer grouting material on the market, the geopolymer grouting material provided by the present invention makes full use of the step hydration properties of f-CaO and f-MgO in the ultrafine steel slag powder to continuously compensate for shrinkage, and can compensate for shrinkage without mixing. Under the action of the expansion agent, micro-expansion occurs, which increases the friction between the solidified body of the grouting material and the soil, thereby significantly improving the bearing capacity. In addition, the grouting material has the characteristics of stable construction performance, good pourability, reaction with soil, early strength and fast hardening, and good volume stability, and is especially suitable for the reinforcement of village and town construction foundations.

The technical features in the claims and/or the description of the present invention can be combined, and the combination is not limited to the combination obtained by reference in the claims. The technical solution obtained by combining the technical features in the claims and/or the description is also the protection scope of the present invention.

The above are only preferred embodiments of the present invention, and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still belong to the present invention. within the scope of the technical solution of the invention.

Claims (10)

1. The geopolymer grouting material is characterized by comprising the following components in percentage by weight:

steel slag: 55.0-65.0%;

slag: 5.0-10.0%;

copper slag: 10.0-15.0%;

carbide slag: 5.0-8.0%;

industrial salt: 3.0-5.0%;

waste gypsum: 5.0-10.0%;

fluid state stabilization modification material: 2.0 to 3.0 percent.

2. The geopolymer grout of claim 1, characterized in that,

the fluid state stable modified material comprises the following components in percentage by weight:

bentonite: 54.0-66.0%;

powdery water reducing agent: 22.0-28.0%;

aluminum slag: 8.0-12.0%;

defoaming agent: 4.0 to 6.0 percent.

3. The geopolymer grout of claim 2, characterized in that,

the powdery water reducing agent is a powdery early-strength polycarboxylic acid high-performance water reducing agent, the inside of the powdery water reducing agent contains 6.0-8.0 wt% of nano CSH nucleating agent, the water reducing rate is more than 30%, the 28-day shrinkage ratio is less than 70%, and the 1-day compressive strength ratio is more than or equal to 200%.

4. The geopolymer grout of claim 2, characterized in that,

the bentonite is ground bentonite ore powder, the content of montmorillonite is more than 60%, and the fineness is 200 meshes;

the aluminum slag is aluminum slag micro powder, and the Bosch specific surface area of the aluminum slag micro powder is 200 +/-20 m²/kg；

The defoaming agent is a powder defoaming agent, and is prepared by adsorbing mineral oil and a nonionic surfactant on an inert carrier.

5. The geopolymer grout of claim 1, characterized in that,

the steel slag is steel slag micro powder, the alkalinity of the steel slag is more than or equal to 2.4, the weight ratio of free calcium oxide is more than or equal to 6.0 percent, the weight ratio of free magnesium oxide is 5.0-8.0 percent, and the Brinell specific surface area is 800 +/-20 m²/kg；

The slag is granulated blast furnace slag powder, the alkalinity coefficient is more than 1.2, the mass coefficient is more than 1.4, and the Boehringer specific surface area is 600 +/-20 m²The water demand is less than 90 percent, and the 28d activity index is more than 110 percent; the copper slag is copper slag micro powder, the content of a vitreous body of the copper slag micro powder is more than 15 percent, and the Brinell specific surface area is 450 +/-20 m²/kg。

6. The geopolymer grout of claim 1, characterized in that,

the carbide slag is carbide slag micro powder, the calcium hydroxide content of the carbide slag micro powder is more than 85 percent, and the Brinell specific surface area is 400 +/-20 m²/kg；

The industrial salt is sun-cured industrial salt, and the sodium chloride content of the industrial salt is more than 96 percent;

the waste gypsum is ground waste gypsum mold powder,the content of sulfur trioxide is more than 46.0 percent, and the Boehringer specific surface area is 400 +/-20 m²/kg。

7. A preparation method of geopolymer grouting material is characterized by comprising the following steps:

the geopolymer grout of any one of claims 1-6 is mixed uniformly.

8. Use of the geopolymer grouting material as defined in any one of claims 1 to 6 in the reinforcement of foundations in villages and small towns construction.

9. The use according to claim 8, comprising:

and adding water into the geopolymer grouting material, stirring and pulping, and then grouting.

10. Use according to claim 9,

the weight of the water is 25.0-30.0% of that of the geopolymer grouting material;

the stirring speed is 10-14 m/s, and the stirring time is 3-5 min.