High-strength geopolymer grouting material and preparation method thereof
The high-strength geopolymer grout formulation addresses the balance of setting time and strength development, enhancing structural integrity and durability for broader engineering applications.
Patent Information
- Application Number
- CN202510515670.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-23
- Publication Date
- 2025-07-15
AI Technical Summary
The existing polyglue grouting materials are difficult to achieve a balance between settling time and early strength increase, resulting in insufficient adaptability under extreme environmental conditions, affecting engineering application and construction stability.
By adjusting the material ratio, adding silicon fume to improve the density, and adjusting the concentration and modulus of the alkali exciter, combining temperature control and humidity management, optimizing the reaction path, and preparing high-strength geopolymer grouting materials.
It significantly improves the early and long-term strength of the geopolymer grouting material, improves toughness and durability, and is suitable for a wider range of engineering application scenarios.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of building materials, and particularly relates to a high-strength geopolymer grouting material and a preparation method thereof. Background Art
[0002] Geopolymer grouting material is an inorganic cementitious material prepared by the reaction of active silica-aluminum materials with an alkali activator. Its raw materials are widely sourced, including industrial solid wastes such as fly ash, slag powder, silica fume, red mud, glass powder, and natural minerals (such as kaolin). Compared with traditional Portland cement-based materials, the production energy consumption of geopolymer grouting material is only 60% of that of Portland cement, and the CO2 emissions are reduced to 10%-20% of it, showing significant low-carbon environmental protection characteristics. Its reaction products are mainly highly cross-linked N-A-S-H gels and a small amount of C-S-H gels, almost free of calcium hydroxide, and the alkalinity of the pore solution is relatively high (pH>13), so it exhibits excellent frost resistance, acid and alkali erosion resistance, and low drying shrinkage. Due to its characteristics such as environmental friendliness and low cost, geopolymer grouting material is widely used in civil engineering, rapid pavement repair, port construction, pile foundation construction and other fields, and has broad application prospects.
[0003] Although geopolymer grouting material shows certain advantages in environmental protection and low cost, its mechanical properties, especially the development of early strength, still have obvious deficiencies. Literature reports that in the process of setting and hardening of existing geopolymer grouting materials, the early strength is usually low due to the relatively slow formation of the internal structure, which cannot meet the engineering applications with some requirements for rapid load-bearing or high strength. In addition, the strength of geopolymer grouting material is not only affected by the chemical composition and ratio of the material itself, but also significantly restricted by environmental conditions such as temperature and humidity. It should be noted that in order to regulate its setting time, a retarder usually needs to be added, but the use of the retarder will not only reduce the material strength, but also increase the production cost, which further limits its wide application in practical engineering. The above problems not only affect the application range of geopolymer grouting material, but also increase the risk of deformation and cracking during the construction process.
[0004] At present, the research of domestic and foreign scholars on improving the mechanical strength of geopolymer grouting materials mainly focuses on optimizing the mix ratio and introducing admixtures. For example, adding reactive fillers (such as fly ash, metakaolin, slag powder, etc.) can promote the polymerization reaction of geopolymers by increasing the reactive centers, thereby improving the overall strength of the material. In addition, the introduction of nanomaterials (such as nano-silicon, nano-aluminum oxide, etc.) has been widely studied. These materials help to significantly improve the early and long-term strength of geopolymer grouting materials by filling micro-pores and enhancing the matrix density. Another method is to adjust the modulus and concentration of the alkali activator to make the reaction more complete, optimize the microstructure of the geopolymer, and thus improve the mechanical properties. In terms of controlling the setting time, geopolymer grouting materials usually need to add retarders to extend the setting time. However, at the same time, the use of retarders will have a certain impact on the material properties, especially reducing the mechanical strength and increasing the production cost, which poses new challenges to engineering applications that require rapid strength development.
[0005] In summary, although the above methods have improved the strength of geopolymer grouting materials to a certain extent, due to complex physical and chemical reactions, the improvement amplitude is still limited, and the adaptability is insufficient under some extreme environmental conditions. Therefore, how to achieve a balance between the flexible control of the setting time and the strength performance has become an important research direction. It is necessary to develop a new retarder system and optimize the reaction path in combination with the unique reaction characteristics of the material to meet the requirements of both engineering performance and economy. Summary of the Invention
[0006] Technical problems to be solved: Aiming at the above technical problems, the present invention provides a high-strength geopolymer grouting material and its preparation method, which can achieve a balance between the flexible control of the setting time and the improvement of strength, especially early strength performance, and has a wider range of engineering application scenarios.
[0007] Technical solution: A high-strength geopolymer grouting material, calculated by mass, comprises raw materials of the following components: Alkali activator, including 10-15 parts of liquid water glass and 5-10 parts of powder water glass; Silico-aluminous material, including 15-45 parts of fly ash, 45-80 parts of slag powder, and 3-5 parts of silica fume; Fine aggregate 25-35 parts; Retarder 3-8 parts; And 20-25 parts of water.
[0008] Preferably, the modulus of both the liquid water glass and the powder water glass is 1.0.
[0009] Preferably, the liquid water glass with a modulus of 1.0 is prepared by mixing with sodium hydroxide solution.
[0010] Preferably, the fine aggregate is river sand.
[0011] Preferably, the fineness modulus of the fine aggregate is 2.7 - 3.0, all belonging to medium sand in Zone II.
[0012] Preferably, the retarder is selected from one or more of barium chloride, hydroxycarboxylate, and borax.
[0013] Preferably, by mass, the retarder includes 3 - 5 parts of borax and 3 - 4 parts of barium chloride.
[0014] The preparation method of the above high-strength geopolymer grouting material includes the following steps: S1. Stir the fine aggregate and the aluminosilicate material together for 3 min to obtain a mixed powder. S2. Mix the retarder and water while stirring, with a mixing time of 1 - 2 min. After mixing, add it to the mixed powder and continue stirring for 1 min to obtain a mixed slurry. S3. Add the alkali activator to the mixed slurry. Among them, the time required to add liquid water glass is 1 - 2 min, and after adding, stir for 2 - 3 min to obtain the high-strength geopolymer grouting material.
[0015] Beneficial effects: As described above, simply by improving the reactivity of the geopolymer grouting material or incorporating high-strength admixtures, although the early strength of the material can be improved to a certain extent, due to complex physical and chemical reactions, the improvement amplitude is still limited, and it is insufficiently adaptable under some extreme environmental conditions, resulting in cracking during actual engineering applications and affecting its long-term service performance. In view of the strength improvement problem of the geopolymer grouting material, the present invention proposes a comprehensive enhancement method. By changing the material ratio, adding silica fume to improve the density, and adjusting the concentration of the alkali activator, multi-faceted improvements in strength, toughness, and durability are achieved. During the preparation process of the geopolymer grouting material, the ratio is reasonably adjusted and silica fume is added to fill the micro-pores in the matrix, significantly improving the density and overall strength of the material; by adjusting the modulus and concentration of the alkali activator, the reaction of the material becomes more uniform, reducing the formation of micro-cracks, thereby enhancing the toughness of the material. In the later curing stage, by placing it in a curing box for appropriate temperature control (20 ± 2°C) and humidity management (≥95%) for 28 d, the internal structure of the material can be further optimized, improving its durability. Finally, the geopolymer grouting material prepared by the present invention not only significantly improves the early and long-term strength, but also effectively improves the toughness and durability, and is applicable to a wider range of engineering application scenarios. Specific embodiments
[0016] The present invention will be further described below in conjunction with specific embodiments. Example 1
[0017] A high-strength geopolymer grouting material, by mass, includes raw materials of the following components: 20 parts of fly ash, 50 parts of slag powder, 3 parts of silica fume, 12 parts of liquid water glass, 6 parts of powder water glass, 26 parts of river sand, 22 parts of water, 3 parts of borax, and 3 parts of barium chloride.
[0018] Among them, the liquid water glass and the powder water glass are alkali activators, and their moduli are both 1.0. The liquid water glass is prepared and used immediately. The preparation method is as follows: Based on the principle that the amount of substance of SiO2 remains unchanged before and after modulation, the mass of the required industrial caustic soda is calculated; then the commercially available water glass and the industrial caustic soda are dissolved, and a glass rod is used for full stirring until the flaky NaOH in the cup disappears, that is, it is fully dissolved in the water glass solution, and finally it is left to stand until it reaches room temperature for use. The powder water glass directly uses commercially available products.
[0019] The river sand is fine aggregate, and the fineness modulus of the fine aggregate is 2.7 - 3.0, all belonging to medium sand in Zone II.
[0020] The borax and barium chloride are retarders. The fly ash, slag powder and silica fume are silica-aluminum materials.
[0021] The preparation method of the above high-strength geopolymer grouting material includes the following steps: S1. Stir the fine aggregate and the silica-aluminum materials together for 3 min to obtain a mixed powder; S2. Mix the retarder with water while stirring, the mixing time is 2 min, and after mixing, add it to the mixed powder and continue to stir for 1 min to obtain a mixed slurry; S3. Add the alkali activator: powder water glass and the prepared water glass solution cooled to room temperature to the mixed slurry in sequence. Among them, the time required to add the liquid water glass is 1 - 2 min, and after adding, stir for 2 - 3 min to obtain the high-strength geopolymer grouting material. Example 2
[0022] A high-strength geopolymer grouting material, by mass, includes raw materials of the following components: 30 parts of fly ash, 60 parts of slag powder, 4 parts of silica fume, 13 parts of liquid water glass, 8 parts of powder water glass, 30 parts of river sand, 23 parts of water, 4 parts of borax, and 3 parts of barium chloride.
[0023] Among them, the liquid water glass and the powder water glass are alkali activators, and their moduli are both 1.0. The liquid water glass is prepared and used immediately. The preparation method is as follows: Based on the principle that the amount of substance of SiO2 remains unchanged before and after modulation, the mass of the required industrial caustic soda is calculated; then the commercially available water glass and the industrial caustic soda are dissolved, and a glass rod is used for full stirring until the flaky NaOH in the cup disappears, that is, it is fully dissolved in the water glass solution, and finally it is left to stand until it reaches room temperature for use. The powder water glass directly uses commercially available products.
[0024] River sand is used as fine aggregate, and the fineness modulus of the fine aggregate is 2.7 - 3.0, both belonging to medium sand in Zone II.
[0025] Borax and barium chloride are retarders. Fly ash, slag powder and silica fume are aluminosilicate materials.
[0026] Its preparation method is the same as that of Example 1. Example 3
[0027] A high-strength geopolymer grouting material, by mass, includes the following raw materials: 40 parts of fly ash, 70 parts of slag powder, 5 parts of silica fume, 14 parts of liquid water glass, 10 parts of powder water glass, 34 parts of river sand, 24 parts of water, 5 parts of borax, and 4 parts of barium chloride.
[0028] Among them, liquid water glass and powder water glass are alkali activators, and the modulus is 1.0. The liquid water glass is prepared and used immediately. The preparation method is as follows: Based on the principle that the amount of substance of SiO2 remains unchanged before and after modulation, the mass of industrial caustic soda required is calculated; then the commercially available water glass and industrial caustic soda are dissolved, and stirred well with a glass rod until the flaky NaOH in the cup disappears, that is, it is fully dissolved in the water glass solution, and finally left to stand until it reaches room temperature for use. The powder water glass directly uses commercially available products.
[0029] River sand is used as fine aggregate, and the fineness modulus of the fine aggregate is 2.7 - 3.0, both belonging to medium sand in Zone II.
[0030] Borax and barium chloride are retarders. Fly ash, slag powder and silica fume are aluminosilicate materials.
[0031] Its preparation method is the same as that of Example 1. Comparative Example 1
[0032] A geopolymer grouting material, by mass, includes the following raw materials: 60 parts of fly ash, 12 parts of liquid water glass, 26 parts of river sand, 22 parts of water, and 3 parts of barium chloride.
[0033] Among them, liquid water glass is an alkali activator, and the modulus is 1.0. The liquid water glass is prepared and used immediately. The preparation method is as follows: Based on the principle that the amount of substance of SiO2 remains unchanged before and after modulation, the mass of industrial caustic soda required is calculated; then the commercially available water glass and industrial caustic soda are dissolved, and stirred well with a glass rod until the flaky NaOH in the cup disappears, that is, it is fully dissolved in the water glass solution, and finally left to stand until it reaches room temperature for use.
[0034] River sand is used as fine aggregate, and the fineness modulus of the fine aggregate is 2.7 - 3.0, both belonging to medium sand in Zone II.
[0035] Barium chloride is a retarder. Fly ash is an aluminosilicate material.
[0036] The preparation method is the same as that of Example 1. Comparative Example 2
[0037] A geopolymer grouting material comprises the following raw materials, measured by weight: 60 parts of mineral powder, 8 parts of powdered water glass, 30 parts of river sand, 23 parts of water, and 4 parts of borax.
[0038] Among them, powdered water glass is an alkali activator, the modulus is 1.0, and a commercially available product is used.
[0039] River sand is fine aggregate, and the fineness modulus of fine aggregate is 2.7-3.0, both of which belong to medium sand in Zone II.
[0040] Borax is a retarder. Mineral powder is a silicon-alumina material.
[0041] The preparation method is the same as that of Example 1. Comparative Example 3
[0042] A geopolymer grouting material comprises the following raw materials by weight: 40 parts of fly ash, 70 parts of mineral powder, 14 parts of liquid water glass, 10 parts of powdered water glass, 34 parts of river sand, 24 parts of water, 5 parts of borax and 4 parts of barium chloride.
[0043] Among them, liquid water glass and powder water glass are alkali activators with a modulus of 1.0. Liquid water glass is prepared and used immediately, and the preparation method is as follows: according to the principle that the amount of SiO2 before and after modulation remains unchanged, the mass of industrial caustic soda required is calculated; then commercially available water glass and industrial caustic soda are dissolved, and stirred with a glass rod until the flaky NaOH in the cup disappears, that is, it is fully dissolved in the water glass solution, and finally allowed to stand to cool to room temperature for use. Powdered water glass uses commercially available products.
[0044] River sand is fine aggregate, and the fineness modulus of fine aggregate is 2.7-3.0, both of which belong to medium sand in Zone II.
[0045] Borax and barium chloride are retarders. Fly ash and mineral powder are silicon-aluminum materials.
[0046] The preparation method is the same as that of Example 1.
[0047] The mechanical properties of compressive strength and fluidity were tested on the above examples and comparative examples, and the results are as follows: Table 1 Mechanical properties test results of geopolymer grouting materials
[0048] As can be seen from the data in the table, with the gradual increase in the content of the two cementitious materials, fly ash and slag powder, in Examples 1 to 3, the compressive strength of the slurry showed a significant upward trend. The 28-day strength was 60.7 MPa, 82.3 MPa, and 88.7 MPa respectively, indicating that the composite cementitious material system can effectively promote strength development. However, at the same time, the initial fluidity decreased from 320 mm to 280 mm, indicating that the increase in the content of active materials led to an increase in the viscosity of the system and a decrease in the fluidity of the slurry. Comparative Example 1 contained only fly ash, and its compressive strength was the lowest, only 32.2 MPa, due to its low reactivity. However, due to the strong hydrophobicity of its particle surface, its fluidity was the highest, reaching 340 mm. Comparative Example 2 was a pure slag powder system. Although it had good strength (80.3 MPa at 28 days), its fluidity was only 170 mm, which was most unfavorable for on-site construction. In Comparative Example 3, no silica fume was added, resulting in its strength (84.9 MPa) being slightly lower than that of Example 3 and its fluidity (290 mm) being slightly higher, indicating that the presence of silica fume helps to enhance the cross-linking reaction and improve the structural compactness.
[0049] Generally speaking, the example group showed good balance in mechanical properties and workability. Especially for Example 3, its compressive strength development was excellent, and it was suitable as a grouting material for engineering applications with high requirements for early strength and final strength. Although individual properties of the comparative example group, such as the 28-day strength of Comparative Example 2, were outstanding, its initial fluidity was low and the early strength development was slow, which limited its scope of application. Therefore, the example group had more comprehensive performance advantages and was suitable for a wide range of engineering needs.
[0050] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A high-strength geopolymer grouting material, characterized in that, Raw materials comprising the following components by mass parts: Alkali activator, including 10 - 15 parts of liquid water glass and 5 - 10 parts of powdery water glass; Silico-aluminous material, including 15 - 45 parts of fly ash, 45 - 80 parts of slag powder, and 3 - 5 parts of silica fume; Fine aggregate 25 - 35 parts; Retarder 3 - 8 parts; And water 20 - 25 parts.
2. The high-strength geopolymer grouting material according to claim 1, wherein The modulus of both the liquid water glass and the powdery water glass is 1.
0.
3. The high-strength geopolymer grouting material according to claim 2, characterized in that, The liquid water glass with a modulus of 1.0 is prepared by blending with sodium hydroxide solution.
4. A high-strength geopolymer grouting material according to claim 1, characterized in that, The fine aggregate is river sand.
5. A high-strength geopolymer grouting material according to claim 1, characterized in that The fineness modulus of the fine aggregate is 2.7 - 3.0, all belonging to medium sand in Zone II.
6. The high-strength geopolymer grouting material according to claim 1, characterized in that, The retarder is selected from one or more of barium chloride, hydroxycarboxylate, and borax.
7. A high-strength geopolymer grouting material according to claim 1, characterized in that, By mass parts, the retarder includes 3 - 5 parts of borax and 3 - 4 parts of barium chloride.
8. The preparation method of the high-strength geopolymer grouting material according to claim 1, characterized in that, The steps are as follows: S1. Stir the fine aggregate and the silico-aluminous material together for 3 min to obtain a mixed powder; S2. Mix the retarder and water while stirring, with the mixing time being 1 - 2 min. After mixing, add it to the mixed powder and continue stirring for 1 min to obtain a mixed slurry; S3. Add the alkali activator to the mixed slurry. Among them, the time required to add the liquid water glass is 1 - 2 min. After adding, stir for 2 - 3 min to obtain the high-strength geopolymer grouting material.