Dispersion-resistant micro-expansion grouting material in dynamic water environment and preparation method thereof

Abstract

The invention relates to the technical field of grouting materials, in particular to a dynamic water environment anti-dispersion micro-expansion grouting material and a preparation method thereof. A component A of the grouting material mainly comprises the following raw materials in parts by weight: 120-160 parts of a gel material with volcanic ash characteristics, 3-5 parts of a retarder, 10-15 parts of magnesium oxide, 0.5-2 parts of citric acid, 5-8 parts of aluminum sulfate, 1-2 parts of sodium fluoride, 0.5-1 part of gelatin and 70-100 parts of water; the component B mainly comprises the following raw materials in parts by weight: 4-8 parts of polyacrylamide, 5-10 parts of polyacrylic acid derivative salt, 1-2 parts of alcohol polysaccharide, 40-100 parts of water glass and 30-50 parts of water; magnesium oxide, aluminum sulfate, gelatin and sodium fluoride in the component A are prepared into core-shell anti-dispersion particles in advance; the problems that a traditional cement grouting material is poor in anti-scouring capacity and anti-dispersing capacity, low in retention rate, poor in stone durability and the like can be solved.

Description

Technical Field

[0001] This invention relates to the field of grouting materials technology, and in particular to a micro-expansion grouting material for dynamic water environments that resists dispersion and its preparation method. Background Technology

[0002] Areas with dynamic water environments have complex hydrogeological structures. The strata are subjected to long-term effects of groundwater circulation, mechanical scouring stress, and seepage, resulting in severe dissolution and mechanical damage to the chemical composition and minerals of the rock layers, leading to the concealment of numerous fracture zones and other structural features. Karst fracture zones are generally characterized by high water content, loose structure, and low bearing capacity under dynamic water conditions. They often contain large amounts of silt and other infill media, making them highly susceptible to sudden water and mud inrushes upon exposure. This can lead to major disasters such as sudden water inrushes in underground engineering projects, large-scale ground subsidence, and deformation and settlement of surface structures, causing serious damage to production safety and the regional environment.

[0003] Materials for controlling sudden water inrush disasters in underground engineering projects (tunnel projects, mining areas, etc.) in karst areas with dynamic water environments are mainly used to prevent groundwater leakage. Traditional cement-based grouting materials have poor erosion and dispersion resistance, low retention rate, and poor durability of the stone body when facing dynamic water environments in underground engineering projects (mining areas) with dynamic water environments. They are difficult to provide core material support for the control of sudden water inrush disasters in underground engineering projects (mining areas) with dynamic water environments for water sealing and grouting reinforcement. Summary of the Invention

[0004] The purpose of this invention is to provide a micro-expansion grouting material for dynamic water environments and its preparation method, which overcomes the shortcomings of the aforementioned prior art and solves the problems of poor scouring and dispersion resistance, low retention rate, and poor durability of traditional cement-based grouting materials. It provides core material support for dynamic water sealing and grouting reinforcement in underground engineering projects for the control of sudden water inrush disasters in karst areas with dynamic water environments.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A micro-expansion grouting material for dynamic water environments, comprising component A and component B, wherein:

[0007] Component A is mainly composed of the following raw materials in parts by weight: 120-160 parts of volcanic ash gel material, 3-5 parts of retarder, 10-15 parts of magnesium oxide, 0.5-2 parts of citric acid, 5-8 parts of aluminum sulfate, 1-2 parts of sodium fluoride, 0.5-1 parts of gelatin, and 70-100 parts of water.

[0008] Component B is mainly composed of the following raw materials in parts by weight: 4-8 parts polyacrylamide, 5-10 parts polyacrylic acid derivative salt, 1-2 parts alcohol polysaccharide, 40-100 parts water glass and 30-50 parts water.

[0009] In this component, magnesium oxide, aluminum sulfate, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 35-40℃. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. The particles are coated with a water-soluble polyvinyl alcohol with a thickness of (1±0.2) mm, wherein the degree of polymerization of the water-soluble polyvinyl alcohol is ≤1000 and the degree of alcoholysis is 70-80%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

[0010] Furthermore, the magnesium oxide is highly active magnesium oxide obtained by calcination at a low temperature of 600-800℃.

[0011] Furthermore, the aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 80-120 mesh.

[0012] Furthermore, the volcanic ash-like gel material is a compound of silicate cement, slag, fly ash and basalt fiber in a weight ratio of (2-3):(2-3):(2-3):(0.5-0.8).

[0013] Furthermore, the retarder is mainly composed of sodium lignosulfonate and borax in a weight ratio of (1-3):(1-1.2).

[0014] Furthermore, the polyacrylate derivative salt is one of sodium polyacrylate, potassium polyacrylate, and zinc polyacrylate.

[0015] Furthermore, the alcohol polysaccharide is one of hydroxypropyl starch, methylcellulose, keryl polysaccharide, sodium gluconate, and sodium alginate.

[0016] Furthermore, the glass is medium modulus water glass, 2.5≤M≤2.8.

[0017] A method for preparing a micro-expansion grouting material with anti-dispersion properties in a dynamic water environment includes the following steps:

[0018] Mix the specified proportions of volcanic ash-based gel material, retarder, citric acid, and water until homogeneous to form slurry A;

[0019] Mix the specified weight parts of polyacrylamide, polyacrylate derivative salt, alcohol polysaccharide and water and stir for 5-10 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B.

[0020] Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 2-3 minutes before use.

[0021] In the formulation of the dynamic water environment anti-dispersion micro-expansion grouting material of the present invention, component A is the main cement-based gel material, and component B is a material that promotes the setting of component A and reacts with component A to enhance its setting strength.

[0022] To improve the anti-dispersion and anti-erosion properties of grouting slurry and increase the retention rate of grouting materials after curing, accelerated hydration methods should be adopted. However, in underground grouting projects in areas with flowing water, there is generally a certain transportation distance, with a transportation time of about 30-40 minutes, and the underground temperature at the plugging point is generally around 50℃-60℃. Conventional accelerated hydration methods are prone to the slurry solidifying before reaching the plugging point. To avoid this situation, this invention innovatively proposes a cement-based anti-dispersion performance control method of "physical coating of hydrated particles - chemical complexation of hydrated ions - accelerated hydration process," and a "core-shell" anti-dispersion structure design for cement-based materials. The specific implementation method is as follows:

[0023] 80% of the raw material aluminum sulfate, which can accelerate coagulation, magnesium oxide (a composite salt and alkali resistant expansion component), and sodium fluoride are bonded together with a small amount of gelatin to form a core structure. The core structure is then coated with a low-polymerization, low-hydrolysis water-soluble polyvinyl alcohol (PVA) doped with another 20% aluminum sulfate to form a shell structure. During the transport of component A, slurry A is slowed down by the retarder. The shell structure of the core-shell anti-dispersion particles melts in approximately 30-60 minutes at room temperature. As slurry A is transported, under the influence of friction, time, and gradually increasing temperature, the outer shell gradually softens, causing some of the aluminum sulfate mixed within to detach from the shell structure. This portion of aluminum sulfate forms a complex with citric acid in slurry A. This complex becomes a hydration-inhibiting film, inhibiting early hydration reactions. When slurry A is mixed with slurry B and reaches the point to be plugged, the raw materials are combined and rubbed, the temperature rises to 50-60℃, and sulfur... The large-scale detachment of aluminum sulfate from the shell layer leads to the overflow of a small amount of magnesium oxide, which reacts with water to generate magnesium hydroxide and heat. Under this effect, the water-soluble polyvinyl alcohol in the shell layer completely dissolves, and a small amount of gelatin also completely dissolves. Aluminum sulfate, which can accelerate hydration and coagulation, completely overflows, and the overflow of sodium fluoride breaks the hydration film inhibition effect of the complex formed by aluminum sulfate and citric acid, allowing the original hydration acceleration effect to continue. This achieves rapid thickening and hydration of the grout. Under the expansion effect of magnesium oxide, the expansion ratio of the rapidly solidified grouting material is about 1.04-1.07, which greatly improves the anti-dispersion and anti-erosion properties of the grouting material and increases the retention rate.

[0024] In addition, the volcanic ash-like gel material is a compound of silicate cement, slag, fly ash and basalt fiber in a weight ratio of (2-3):(2-3):(2-3):(0.5-0.8). Through the compatibility of efficient synergy and complementarity of multi-source solid waste, the combination of multi-source solid waste mineral phase composition is realized from the perspective of physicochemical and mineral phase, which promotes the improvement of overall mechanical properties.

[0025] In this invention, magnesium oxide obtained by calcination at 600-800℃ is selected. This type of magnesium oxide is highly active. When it overflows from the core structure, it reacts rapidly with water and releases heat in a concentrated manner. In a short time, it can accelerate the melting of the shell structure by increasing the temperature of the core structure. After the reaction is completed, at the ambient temperature of the plugging point, water-soluble polyvinyl alcohol dispersed in the material comes into contact with other cement-based components and easily forms lumps.

[0026] Adding an appropriate amount of water to component B promotes the fluidity of water glass, adding an appropriate amount of polyacrylamide promotes the fluidity and improves the stability of water glass, and adding an appropriate amount of polyacrylic acid derivative salt improves the dispersibility of water glass. The appropriate addition of these raw materials promotes the smooth delivery of water glass with a modulus between 2.5 and 2.8 to be mixed with component A under the target environment while maintaining component stability and good fluidity.

[0027] The beneficial effects of this invention are as follows: Compared with the prior art, the anti-dispersion micro-expansion grouting material and its preparation method for dynamic water environment of this invention have the following advantages: It solves the problems of poor anti-scouring and anti-dispersion ability, low retention rate and poor durability of traditional cement-based grouting materials, and provides core material support for dynamic water sealing and grouting reinforcement in the treatment of sudden water inrush disasters in underground engineering (mining area) in dynamic water environment karst area. Detailed Implementation

[0028] Example 1

[0029] This embodiment of a hydrodynamic environment anti-dispersion micro-expansion grouting material includes component A and component B, wherein:

[0030] Component A is mainly composed of the following raw materials in parts by weight: 142 parts of volcanic ash gel material, 4 parts of retarder, 12 parts of magnesium oxide, 1.3 parts of citric acid, 6 parts of aluminum sulfate, 2 parts of sodium fluoride, 0.8 parts of gelatin, and 88 parts of water.

[0031] Component B is mainly composed of the following raw materials in parts by weight: 6 parts polyacrylamide, 7 parts polyacrylic acid derivative salt, 1 part alcohol polysaccharide, 70 parts water glass and 40 parts water.

[0032] In this component, magnesium oxide, aluminum sulfate, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 38°C. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. The particles are coated with a water-soluble polyvinyl alcohol with a thickness of (1±0.2) mm. The water-soluble polyvinyl alcohol has a degree of polymerization of 1000 and a degree of alcoholysis of 80%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

[0033] In this embodiment, the magnesium oxide is highly active magnesium oxide calcined at a low temperature of 800℃. The aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 100 mesh. The volcanic ash-like gelling material is a compound of silicate cement, slag, fly ash, and basalt fiber in a weight ratio of 3:2:2:0.7. The retarder is mainly a compound of sodium lignosulfonate and borax in a weight ratio of 2:1.1. The polyacrylate derivative is potassium polyacrylate. The alcohol polysaccharide is hydroxypropyl starch. The glass is medium-modulus water glass, M=2.6.

[0034] The preparation method of the anti-dispersion micro-expansion grouting material in dynamic water environment of this embodiment includes the following steps:

[0035] Mix the specified proportions of volcanic ash-based gel material, retarder, citric acid, and water until homogeneous to form slurry A;

[0036] Mix the specified weight parts of polyacrylamide, polyacrylate derivative salt, alcohol polysaccharide and water and stir for 8 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B.

[0037] Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 3 minutes before use.

[0038] At the water inrush point of underground engineering in a karst area with a dynamic water environment and an ambient temperature of 50-60℃, when using the material of this embodiment, components A and B are respectively delivered through the double-walled drill pipe of the dual-liquid grouting system. Delivery takes approximately 32 minutes to reach the water-blocking point. Components A and B initially set at the water-blocking point after approximately 50-80 seconds. Testing showed that the grout retention rate at a dynamic water flow velocity of 1.2 m / s was >85%; the 28-day flexural strength of the slab was >4.4 MPa, and the 28-day compressive strength was >7.6 MPa; it contained 2% Cl... - and SO4 2- The 28-day compressive strength of the stone body under liquid erosion conditions is >4.2 MPa.

[0039] Example 2

[0040] The anti-dispersion micro-expansion grouting material for dynamic water environment in this embodiment includes component A and component B, wherein:

[0041] Component A is mainly composed of the following raw materials in parts by weight: 160 parts of volcanic ash gel material, 5 parts of retarder, 15 parts of magnesium oxide, 2 parts of citric acid, 8 parts of aluminum sulfate, 2 parts of sodium fluoride, 1 part of gelatin, and 100 parts of water.

[0042] Component B is mainly composed of the following raw materials in parts by weight: 8 parts polyacrylamide, 10 parts polyacrylic acid derivative salt, 2 parts alcohol polysaccharide, 100 parts water glass and 50 parts water.

[0043] In this component, magnesium oxide, aluminum sulfate, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 40°C. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. The particles are coated with a water-soluble polyvinyl alcohol with a thickness of (1±0.2) mm. The water-soluble polyvinyl alcohol has a degree of polymerization of 800 and a degree of alcoholysis of 70%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

[0044] In this embodiment, the magnesium oxide is highly active magnesium oxide calcined at a low temperature of 700℃. The aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 120 mesh. The volcanic ash-like gelling material is a compound of silicate cement, slag, fly ash, and basalt fiber in a weight ratio of 3:3:2:0.8. The retarder is mainly a compound of sodium lignosulfonate and borax in a weight ratio of 3:1.2. The polyacrylate derivative is zinc polyacrylate. The alcohol polysaccharide is sodium gluconate. The glass is medium-modulus water glass with M=2.8.

[0045] The preparation method of the anti-dispersion micro-expansion grouting material in dynamic water environment of this embodiment includes the following steps:

[0046] Mix the specified proportions of volcanic ash-based gel material, retarder, citric acid, and water until homogeneous to form slurry A;

[0047] Mix the specified weight parts of polyacrylamide, polyacrylate derivative salt, alcohol polysaccharide and water and stir for 10 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B.

[0048] Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 3 minutes before use.

[0049] At the water inflow point of underground engineering in a karst area with a dynamic water environment and an ambient temperature of 50-60℃, when using the material of this embodiment, components A and B are respectively delivered through the double-walled drill rod of the dual-liquid grouting system. Delivery takes approximately 35 minutes to reach the water-blocking point. Components A and B initially set at the water-blocking point after approximately 50-70 seconds. Testing showed that the grout retention rate was >80% at a dynamic water flow velocity of 1.2 m / s; the 28-day flexural strength of the slab was >4.2 MPa, and the 28-day compressive strength was >7.3 MPa; it contained 2% Cl... - and SO4 2- The 28-day compressive strength of the stone body under liquid erosion conditions is >4 MPa.

[0050] Example 3

[0051] The anti-dispersion micro-expansion grouting material for dynamic water environment in this embodiment includes component A and component B, wherein:

[0052] Component A is mainly composed of the following raw materials in parts by weight: 120 parts of volcanic ash gel material, 3 parts of retarder, 10 parts of magnesium oxide, 0.5 parts of citric acid, 5 parts of aluminum sulfate, 1 part of sodium fluoride, 0.5 parts of gelatin, and 70 parts of water.

[0053] Component B is mainly composed of the following raw materials in parts by weight: 4 parts polyacrylamide, 5 parts polyacrylic acid derivative salt, 1 part alcohol polysaccharide, 40 parts water glass and 30 parts water.

[0054] In this component, magnesium oxide, aluminum sulfate, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 35°C. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. The particles are coated with a water-soluble polyvinyl alcohol with a thickness of (1±0.2) mm. The water-soluble polyvinyl alcohol has a degree of polymerization of 800 and a degree of alcoholysis of 70%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

[0055] In this embodiment, the magnesium oxide is highly active magnesium oxide calcined at a low temperature of 600℃. The aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 80 mesh. The volcanic ash-like gelling material is a compound of silicate cement, slag, fly ash, and basalt fiber in a weight ratio of 2:2:3:0.5. The retarder is mainly a compound of sodium lignosulfonate and borax in a weight ratio of 1:1. The polyacrylate derivative is sodium polyacrylate. The alcohol polysaccharide is sodium alginate. The glass is medium modulus water glass with M=2.5.

[0056] The preparation method of the anti-dispersion micro-expansion grouting material in dynamic water environment of this embodiment includes the following steps:

[0057] Mix the specified proportions of volcanic ash-based gel material, retarder, citric acid, and water until homogeneous to form slurry A;

[0058] Mix the specified weight parts of polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water and stir for 5 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B.

[0059] Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 2 minutes before use.

[0060] At the water inflow point of underground engineering in a karst area with a dynamic water environment and an ambient temperature of 50-60℃, when using the material of this embodiment, components A and B are respectively delivered through the double-walled drill pipe of the dual-liquid grouting system. Delivery takes approximately 30 minutes to reach the water-blocking point, and components A and B initially set at the water-blocking point after about 60-80 seconds. Testing showed that the grout retention rate was >82% at a dynamic water flow velocity of 1.2 m / s; the 28-day flexural strength of the slab was >4 MPa, and the 28-day compressive strength was >7.2 MPa; it contained 2% Cl... - and SO4 2- The 28-day compressive strength of the stone body under liquid erosion conditions is >4 MPa.

[0061] Example 4

[0062] This embodiment of a hydrodynamic environment anti-dispersion micro-expansion grouting material includes component A and component B, wherein:

[0063] Component A is mainly composed of the following raw materials in parts by weight: 142 parts of volcanic ash gel material, 4 parts of retarder, 12 parts of magnesium oxide, 1.3 parts of citric acid, 6 parts of aluminum sulfate, 2 parts of sodium fluoride, 0.8 parts of gelatin, and 88 parts of water.

[0064] Component B is mainly composed of the following raw materials in parts by weight: 6 parts polyacrylamide, 7 parts polyacrylic acid derivative salt, 1 part alcohol polysaccharide, 70 parts water glass and 40 parts water.

[0065] In this component, magnesium oxide, aluminum sulfate, citric acid, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, citric acid, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 38°C. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. The particles are coated with a water-soluble polyvinyl alcohol with a thickness of (1±0.2) mm, wherein the degree of polymerization of the water-soluble polyvinyl alcohol is 1000 and the degree of alcoholysis is 80%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

[0066] In this embodiment, the magnesium oxide is highly active magnesium oxide calcined at a low temperature of 800℃. The aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 100 mesh. The volcanic ash-like gelling material is a compound of silicate cement, slag, fly ash, and basalt fiber in a weight ratio of 3:2:2:0.7. The retarder is mainly a compound of sodium lignosulfonate and borax in a weight ratio of 2:1.1. The polyacrylate derivative is potassium polyacrylate. The alcohol polysaccharide is hydroxypropyl starch. The glass is medium-modulus water glass, M=2.6.

[0067] The preparation method of the anti-dispersion micro-expansion grouting material in dynamic water environment of this embodiment includes the following steps:

[0068] Mix the specified proportions of volcanic ash-based gel material, retarder, and water until homogeneous to form slurry A;

[0069] Mix the specified weight parts of polyacrylamide, polyacrylate derivative salt, alcohol polysaccharide and water and stir for 8 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B.

[0070] Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 3 minutes before use.

[0071] At the underground engineering water point in a karst area with a dynamic water environment and an ambient temperature of 50-60℃, when using the material of this embodiment, components A and B were delivered separately through the double-walled drill pipe of the dual-liquid grouting system. After about 28 minutes of delivery, component A showed premature solidification when it reached the later stage, but this did not lead to serious blockage. After continuing delivery for 5 minutes, serious blockage occurred when it reached the mixing section of components A and B. The operators immediately stopped the grouting operation, shut down all relevant valves and pumping devices, and carried out unblocking operations. The reason for the premature blockage may be that citric acid was added to the core-shell anti-dispersion particles. The 20% aluminum sulfate doped in the shell structure could not form a complex with citric acid to inhibit hydration. In addition, aluminum sulfate has the effect of accelerating hydration, which led to the initial solidification of component A when it reached the later stage, causing the overall flow rate of component A to decrease until more serious initial solidification occurred when components A and B were mixed.

[0072] The above-described specific embodiments are merely specific examples of the present invention. The patent protection scope of the present invention includes, but is not limited to, the product form and style of the above-described specific embodiments. Any appropriate changes or modifications made by a person skilled in the art that conform to the claims of the present invention should fall within the patent protection scope of the present invention.

Claims

1. A micro-expansion grouting material for dynamic water environments, characterized in that, Includes component A and component B; Component A is mainly composed of the following raw materials in parts by weight: 120-160 parts of volcanic ash gel material, 3-5 parts of retarder, 10-15 parts of magnesium oxide, 0.5-2 parts of citric acid, 5-8 parts of aluminum sulfate, 1-2 parts of sodium fluoride, 0.5-1 parts of gelatin, and 70-100 parts of water. Component B is mainly composed of the following raw materials in parts by weight: 4-8 parts polyacrylamide, 5-10 parts polyacrylic acid derivative salt, 1-2 parts alcohol polysaccharide, 40-100 parts water glass and 30-50 parts water. In this component, magnesium oxide, aluminum sulfate, gelatin, and sodium fluoride are pre-prepared into core-shell anti-dispersibility particles. The preparation method includes the following steps: magnesium oxide, sodium fluoride, gelatin, and 80% aluminum sulfate are stirred into a mixture at 35-40℃. After the mixture cools and solidifies, it is broken into particles of 2-5 mm. A 1 ± 0.2 mm thick layer of water-soluble polyvinyl alcohol is coated on the outside of the particles. The degree of polymerization of the water-soluble polyvinyl alcohol is ≤1000 and the degree of alcoholysis is 70-80%. The remaining 20% ​​aluminum sulfate is pre-dispersed in the water-soluble polyvinyl alcohol.

2. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The magnesium oxide is a highly active magnesium oxide obtained by calcination at a low temperature of 600-800℃.

3. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The aluminum sulfate premixed with water-soluble polyvinyl alcohol is pulverized to a particle size of 80-120 mesh.

4. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The volcanic ash-like gel material is a compound of silicate cement, slag, fly ash and basalt fiber in a weight ratio of (2-3):(2-3):(2-3):(0.5-0.8).

5. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The retarder is mainly composed of sodium lignosulfonate and borax in a weight ratio of (1-3):(1-1.2).

6. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The polyacrylate derivative is one of sodium polyacrylate, potassium polyacrylate, and zinc polyacrylate.

7. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The alcohol polysaccharide is one of hydroxypropyl starch, methylcellulose, keryl polysaccharide, sodium gluconate, and sodium alginate.

8. The anti-dispersion micro-expansion grouting material for dynamic water environments according to claim 1, characterized in that, The water glass is medium modulus water glass, with a modulus of 2.5 ≤ M ≤ 2.

8.

9. A method for preparing a micro-expansion grouting material for dynamic water environment according to any one of claims 1-8, characterized in that, Includes the following steps: Mix the specified proportions of volcanic ash-based gel material, retarder, citric acid, and water until homogeneous to form slurry A; Mix the specified weight parts of polyacrylamide, polyacrylate derivative salt, alcohol polysaccharide and water and stir for 5-10 minutes. Then, while mixing, add the specified weight parts of water glass and continue stirring until uniform to form slurry B. Slurry A and slurry B are used for two-liquid grouting. Before the two-liquid grouting operation, the pre-prepared core-shell anti-dispersion particles are added to slurry A and stirred for 2-3 minutes before use.