A high-temperature resistant grouting water blocking material for underground engineering and its preparation method

Abstract

The present invention relates to the technical field of grouting materials, and in particular to a high-temperature resistant grouting and water-blocking material for underground engineering and a preparation method thereof. The high-temperature resistant grouting and water-blocking material for underground engineering comprises a component A and a component B. Component A is mainly composed of the following raw materials in parts by weight: a gel material with volcanic ash properties, a retarder, an expansion agent, a low-melting-point hot-melt adhesive, calcium oxide, and water; component B is mainly composed of the following raw materials in parts by weight: polyacrylamide, polyacrylic acid derivative salts, alcohol polysaccharides, water glass, and water; the expansion agent, low-melting-point hot-melt adhesive, calcium oxide, and 20-30% of the retarder in component A are prepared into slow-setting expansion particles for use. The present invention satisfies the requirement that the grouting and water-blocking material begins to coagulate rapidly only after reaching the leak point under long-distance transportation conditions, and can maintain good thermal stability at 20-60°C after coagulation, and has high bonding strength.

Description

Technical Field

[0001] The invention relates to the technical field of grouting materials, in particular to a high-temperature resistant grouting and water-blocking material for underground engineering and a preparation method thereof. Background Art

[0002] Grouting materials in underground projects are key materials used to prevent groundwater seepage, reinforce strata, and improve structural stability. Selecting the right grouting material is crucial to ensuring the safety and durability of the project.

[0003] During the grouting process of underground projects, due to the location of the water blocking point, some projects require long-distance grouting transportation, and the underground ambient temperature is between 40-60°C, which is a high-temperature environment. Under such conditions, the current grouting water blocking materials have the following main shortcomings: (1) The slurry begins to coagulate before reaching the leaking point, seriously affecting the smooth transportation of the slurry and the water blocking effect; (2) The material has poor high temperature resistance, poor thermal stability in the 40-60°C environment, and the bonding strength does not meet the requirements. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-temperature resistant grouting and water-blocking material for underground engineering and a preparation method thereof, to overcome the shortcomings of the aforementioned prior art, to meet the conditions of long-distance transportation, in which the grouting and water-blocking material begins to rapidly solidify after reaching the leakage point, the initial setting time of the material is between 15-30 minutes, and after solidification, it can maintain good thermal stability in an environment of 20-60°C and has high bonding strength.

[0005] The technical solution adopted by the present invention to solve the technical problem is:

[0006] A high-temperature resistant grouting and water-blocking material for underground engineering comprises a component A and a component B. Component A is mainly composed of the following raw materials in parts by weight: 120-160 parts of a gel material with volcanic ash properties, 4-6 parts of a retarder, 10-15 parts of an expansion agent, 12-18 parts of a low-melting-point hot-melt adhesive, 20-35 parts of calcium oxide, and 80-100 parts of water. Component B is mainly composed of the following raw materials in parts by weight: 3-8 parts of polyacrylamide, 5-10 parts of a polyacrylic acid derivative salt, 1.25-3 parts of an alcohol polysaccharide, 50-120 parts of water glass, and 30-50 parts of water. The expansion agent, low-melting-point hot-melt adhesive, calcium oxide, and 20-30% of the retarder in component A are prepared into retarded expansion particles for use. The preparation method comprises the following steps:

[0007] Under a temperature environment above the melting point of the low-melting-point hot melt adhesive, an expansion agent, a low-melting-point hot melt adhesive, calcium oxide, and a retarder in a weight ratio of 20-30% are stirred uniformly to form a mixture. After the mixture is cooled and solidified, it is broken into 2-5 mm particles, and the outside of the particles is coated with a 0.2-0.3 mm water-soluble polyvinyl alcohol film;

[0008] The low-melting-point hot-melt adhesive has a melting point higher than the ambient temperature of the grouting water blocking point and lower than the heat generation temperature of the reaction between calcium oxide and water.

[0009] Preferably, the 0.2-0.3 mm water-soluble polyvinyl alcohol film is an NT-type film, and its dissolution time is 25-45 min at 20-35° C.

[0010] Preferably, the water glass is medium modulus water glass, 2.5≤M≤2.8.

[0011] Preferably, the gel material with pozzolanic properties is prepared by compounding silicate cement and fly ash in a weight ratio of (1-1.5): (3-5).

[0012] Preferably, the retarder is mainly composed of sodium lignin sulfonate and borax in a weight ratio of (2-3):1.

[0013] Preferably, the expansion agent is a compound of multiple ingredients selected from cross-linked polyacrylate, sodium lauryl sulfonate, sodium lauryl sulfate, aluminum lauryl sulfate, sodium α-olefin sulfonate, and aluminum powder, with a weight ratio of (0.8-1.2): (0.8-1.2): (0.4-0.8): (0.4-0.8): (20-30): (8-12).

[0014] Preferably, the low melting point hot melt adhesive is one of EVA hot melt adhesive, polyester hot melt adhesive, polyester amide hot melt adhesive, polyolefin hot melt adhesive, and rubber-based hot melt adhesive.

[0015] Preferably, the polyacrylic acid derivative salt is one of sodium polyacrylate, potassium polyacrylate, calcium polyacrylate, and zinc polyacrylate.

[0016] Preferably, the alcohol polysaccharide is one of polyethylene glycol-2000, sodium gluconate, sodium alginate, and calendulose.

[0017] A method for preparing a high-temperature resistant grouting and water-blocking material for underground engineering, wherein the method for preparing component A comprises the following steps:

[0018] Pre-prepare slow-setting expansion particles;

[0019] Mix the specified weight proportions of the pozzolanic gel material and water and stir evenly, then add the remaining 20-30% of the retarder and continue mixing evenly to form slurry A;

[0020] The retarding expansion particles and slurry A are set aside separately;

[0021] The preparation method of the B component comprises the following steps:

[0022] Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 5-10 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B;

[0023] When using high temperature resistant grouting and water blocking materials for underground projects, component A and component B are grouted with two liquids. Before the two liquid grouting operation, the slow setting expansion particles are added to the slurry A and stirred for 2-3 minutes before use.

[0024] Among the components of this material, component A is the main cement-based gel material, and component B is a material that promotes the coagulation of component A and reacts with component A to enhance its coagulation strength.

[0025] The functions of each raw material in component A are:

[0026] The pozzolanic gel material is made of Portland cement and fly ash in a weight ratio of (1-1.5): (3-5). The high proportion of fly ash makes it more fluid than slurries with a high proportion of Portland cement. Furthermore, as Portland cement hydrates to produce calcium hydroxide, the fly ash also gradually hydrates under the action of calcium hydroxide and water. Especially when there is an excess of calcium hydroxide, the fly ash hydration reaction can continue for a long time. Therefore, in the later stages of the plugging process, the strength of the plugged area will continue to increase, demonstrating better long-term performance.

[0027] The volcanic ash gel material is mixed with water at a high water-cement ratio, and has good fluidity. Under the influence of the retarder, it is not easy to coagulate prematurely even if the transportation time is as long as 15-30 minutes, and has good fluidity.

[0028] In the retarding expansion particles, the expansion agent, low-melting point hot melt adhesive, calcium oxide and a small amount of retarder are mixed and condensed, then broken and coated with a 0.2-0.3mm water-soluble polyvinyl alcohol film. The 0.2-0.3mm water-soluble polyvinyl alcohol film is an NT-type film, which dissolves in 25-45 minutes at 20-35°C. During the stirring and conveying process of the retarding expansion particles, the friction between the raw materials and the increase in ambient temperature will increase the dissolution rate of the water-soluble polyvinyl alcohol film, shortening the dissolution time to 10-25 minutes. When the retarding expansion particles begin to dissolve, part of the calcium oxide inside them comes into contact with water, and the calcium oxide reacts with water:

[0029] CaO+H2O→Ca(OH)2

[0030] Heat and calcium hydroxide are generated. This reaction process is carried out gradually after the water-soluble polyvinyl alcohol film is exposed and the internal material is exposed. It lasts for 2-5 minutes. Although the heat is not greatly diffused by the surrounding environment, it melts the low-melting-point hot melt condensed around it, releasing more calcium oxide, and at the same time releasing expansion agent and a small amount of retarder. The molecules of the expansion agent have both hydrophilic and hydrophobic groups. Under the action of slurry transportation, calcium oxide reaction, and turbulence formed by mixing with the component wall, denser small bubbles will be formed, which will cause the slurry to expand in volume when entering the area to be blocked, thereby increasing its water blocking and sealing effect. The retarder further plays the role of slowing down the solidification after the water-soluble polyvinyl alcohol film is dissolved.

[0031] The functions of each raw material in component B are:

[0032] The modulus of water glass is selected: 2.5≤M≤2.8, which is a medium to high modulus. It has good adhesion and can promote the high-strength condensation of gel materials with volcanic ash characteristics, but its fluidity is lower than that of water glass with M<2. Adding an appropriate amount of water to component B can promote the fluidity of water glass, adding an appropriate amount of polyacrylamide can promote the fluidity of water glass and improve the stability of water glass, adding an appropriate amount of polyacrylic acid derivative salt can improve the dispersibility of water glass. The appropriate addition and coordination of these raw materials promotes the smooth and stable transportation of water glass with a modulus between 2.5-2.8 for 15-30 minutes to mix with component A.

[0033] When components A and B are mixed in a two-liquid grouting process, the components impact each other during mixing. In component A, the cement hydrates to form some calcium hydroxide, while the calcium oxide reacts with water to form some calcium hydroxide. This calcium hydroxide reacts with water glass to form calcium silicate gel (CSH):

[0034]

[0035] The formation of key products that enhance the strength after setting also maintains an alkaline environment formed by calcium hydroxide and sodium hydroxide, which is crucial for preventing steel corrosion and is beneficial to the stability and long-term performance of certain mineral phases (such as CSH gel).

[0036] Since the A component contains oil-containing low-melting-point hot melt adhesive, its melting point is higher than the ambient temperature of the grouting water blocking point and lower than the heat generation temperature of the reaction between calcium oxide and water. Therefore, after the calcium oxide reaction is complete, the low-melting-point hot melt adhesive will return to a solidified state. Under the action of the cross-flow force generated by the calcium oxide reaction, the solidified state of the low-melting-point hot melt adhesive is an irregular shape, which is easy to adhere to and bond to the surrounding structure when the slurry solidifies, thereby improving the overall strength of the structure.

[0037] The present invention has the following beneficial effects: Compared with the prior art, the high-temperature resistant grouting water-blocking material for underground engineering and the preparation method thereof have the following advantages: both components A and B have good fluidity, meeting the conditions for long-distance transportation, and the initial setting time of the material is between 15 and 30 minutes. Under the action of the retarding expansion particles, component A begins to release the swelling agent only before being transported to mix with component B, causing the slurry to expand in volume when entering the area to be blocked, thereby enhancing its water-blocking and sealing effect. After the calcium oxide reaction is complete, the low-melting point hot melt adhesive will return to a solidified state. Under the action of the cross-flow force generated by the calcium oxide reaction, the low-melting point hot melt adhesive solidifies into an irregular shape, easily adhering to and bonding to surrounding structures during the solidification of the slurry, thereby improving the overall strength of the structure. During the mixing process of components A and B, an alkaline environment of calcium hydroxide and sodium hydroxide is formed. This alkaline environment is crucial for preventing steel corrosion and is beneficial to the stability and long-term performance of certain mineral phases (such as CSH gel). The fly ash hydration reaction can continue for a long time. Therefore, in the later stage of the water blocking, the strength of the blocked area will continue to increase, demonstrating better long-term performance. DETAILED DESCRIPTION

[0038] Example 1

[0039] A high-temperature resistant grouting and water-blocking material for underground engineering, comprising component A and component B. Component A is primarily composed of the following raw materials in parts by weight: 140 parts of a volcanic ash gel material, 5 parts of a retarder, 12 parts of an expansion agent, 15 parts of a low-melting-point hot-melt adhesive, 38 parts of calcium oxide, and 94 parts of water; and component B is primarily composed of the following raw materials in parts by weight: 6 parts of polyacrylamide, 7 parts of a polyacrylic acid derivative salt, 2.38 parts of an alcohol polysaccharide, 88 parts of water glass, and 45 parts of water.

[0040] Among the above raw materials, the pozzolanic gel material is a mixture of Portland cement and fly ash in a weight ratio of 1.344:4.2. The retarder is primarily composed of sodium lignin sulfonate and borax in a weight ratio of 2.6:1. The expansion agent is a mixture of cross-linked polyacrylate, sodium dodecyl sulfonate, sodium dodecyl sulfate, aluminum dodecyl sulfate, sodium α-olefin sulfonate, and aluminum powder in a weight ratio of 1:1:0.5:0.8:22:8. The low-melting-point hot-melt adhesive is an EVA hot-melt adhesive. The polyacrylic acid derivative salt is calcium polyacrylate. The alcohol polysaccharide is polyethylene glycol-2000. The water glass is a medium-modulus water glass with an M=2.6.

[0041] The underground engineering high temperature resistant grouting water blocking material of this embodiment has an ambient temperature of 55-60°C at the water blocking point.

[0042] The melting point of low melting point hot melt adhesive is 80℃.

[0043] In this embodiment, the expansion agent, low melting point hot melt adhesive, calcium oxide and 25% of retarder in component A are prepared into retarded expansion particles for use.

[0044] The preparation method of the underground engineering high-temperature resistant grouting and water blocking material of this embodiment, the preparation method of the said component A comprises the following steps:

[0045] Prepare retarded intumescent particles in advance. At 100°C, stir an intumescent agent, a low-melting-point hot-melt adhesive, calcium oxide, and 25% by weight of a retarder to form a mixture. After the mixture cools and solidifies, break it into 2-5 mm particles. Cover the particles with a 0.3 mm water-soluble polyvinyl alcohol film. The 0.3 mm water-soluble polyvinyl alcohol film is an NT-type film that dissolves in 45 minutes at room temperature.

[0046] The volcanic ash gel material and water in the prescribed weight proportions are mixed and stirred until uniformly mixed, and the remaining 75% of the retarder is added and continued to be stirred and mixed until uniformly mixed to form slurry A;

[0047] The retarding expansion particles and slurry A are set aside separately;

[0048] The preparation method of the B component comprises the following steps:

[0049] Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 8 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B;

[0050] When using high temperature resistant grouting and water blocking materials in underground projects, component A and component B are grouted with two liquids. Before the two liquid grouting operation, the slow setting expansion particles are added to the slurry A and stirred for 3 minutes before use.

[0051] During use, the dual-liquid grouting system delivers component A and component B separately through the double-walled drill pipe. The delivery takes about 28 minutes to reach the water blocking point. At an ambient temperature between 55-60°C, components A and B initially set at the water blocking point after about one minute. The compressive strength of the stone is 1.5 MPa after one day of setting, 6 MPa after three days, and 14 MPa after 10 days.

[0052] Example 2

[0053] A high-temperature resistant grouting and water-blocking material for underground engineering, comprising component A and component B. Component A is primarily composed of the following raw materials in parts by weight: 120 parts of a volcanic ash gel material, 4 parts of a retarder, 10 parts of an expansion agent, 12 parts of a low-melting-point hot-melt adhesive, 20 parts of calcium oxide, and 80 parts of water; and component B is primarily composed of the following raw materials in parts by weight: 3 parts of polyacrylamide, 5 parts of a polyacrylic acid derivative salt, 1.25 parts of an alcohol polysaccharide, 50 parts of water glass, and 30 parts of water.

[0054] Among the above raw materials, the pozzolanic gel material is a mixture of Portland cement and fly ash in a weight ratio of 1:3.2. The retarder is primarily composed of sodium lignin sulfonate and borax in a weight ratio of 2:1. The expansion agent is a mixture of cross-linked polyacrylate, sodium dodecyl sulfonate, sodium dodecyl sulfate, aluminum dodecyl sulfate, sodium α-olefin sulfonate, and aluminum powder in a weight ratio of 1:1:0.7:0.75:28:8. The low-melting-point hot-melt adhesive is a polyester hot-melt adhesive. The polyacrylic acid derivative salt is sodium polyacrylate. The alcohol polysaccharide is sodium alginate. The water glass is a medium-modulus water glass with an M=2.5.

[0055] The underground engineering high temperature resistant grouting water blocking material of this embodiment has an ambient temperature of 40-45°C at the water blocking point.

[0056] The melting point of low melting point hot melt adhesive is 85℃.

[0057] In this embodiment, the expansion agent, low melting point hot melt adhesive, calcium oxide and 20% of retarder in component A are prepared into retarded expansion particles for use.

[0058] The preparation method of the underground engineering high-temperature resistant grouting and water blocking material of this embodiment, the preparation method of the said component A comprises the following steps:

[0059] Prepare retarded intumescent particles in advance. At 100°C, stir an intumescent agent, a low-melting-point hot-melt adhesive, calcium oxide, and 20% by weight of a retarder to form a mixture. After the mixture cools and solidifies, break it into 2-5 mm particles. Cover the particles with a 0.2 mm water-soluble polyvinyl alcohol film. The 0.2 mm water-soluble polyvinyl alcohol film is an NT-type film that dissolves in 25 minutes at room temperature.

[0060] The volcanic ash gel material and water in the prescribed weight proportions are mixed and stirred evenly, and the remaining 80% of the retarder is added and continued to be mixed evenly to form slurry A;

[0061] The retarding expansion particles and slurry A are set aside separately;

[0062] The preparation method of the B component comprises the following steps:

[0063] Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 5 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B;

[0064] When using high temperature resistant grouting and water blocking materials for underground projects, component A and component B are grouted with two liquids. Before the two liquid grouting operation, the slow setting expansion particles are added to the slurry A and stirred for 2 minutes before use.

[0065] During use, the dual-liquid grouting system delivers component A and component B separately through the double-walled drill pipe. The delivery takes about 13 minutes to reach the water blocking point. At an ambient temperature between 40-45°C, components A and B initially set at the water blocking point after about one minute. The compressive strength of the stone is 1.2 MPa after one day of setting, 4.5 MPa after three days, and 12 MPa after 10 days.

[0066] Example 3

[0067] A high-temperature resistant grouting and water-blocking material for underground engineering, comprising component A and component B. Component A is primarily composed of the following raw materials in parts by weight: 160 parts of a volcanic ash gel material, 6 parts of a retarder, 15 parts of an expansion agent, 18 parts of a low-melting-point hot-melt adhesive, 35 parts of calcium oxide, and 100 parts of water; and component B is primarily composed of the following raw materials in parts by weight: 8 parts of polyacrylamide, 10 parts of a polyacrylic acid derivative salt, 3 parts of an alcohol polysaccharide, 120 parts of water glass, and 50 parts of water.

[0068] Among the above raw materials, the pozzolanic gel material is a mixture of Portland cement and fly ash in a weight ratio of 1.5:5. The retarder is primarily composed of sodium lignin sulfonate and borax in a weight ratio of 3:1. The expansion agent is a mixture of cross-linked polyacrylate, sodium dodecyl sulfonate, sodium dodecyl sulfate, aluminum dodecyl sulfate, sodium α-olefin sulfonate, and aluminum powder in a weight ratio of 1:1:0.5:0.6:20:11. The low-melting-point hot-melt adhesive is a polyesteramide hot-melt adhesive. The polyacrylic acid derivative salt is calcium polyacrylate. The alcohol polysaccharide is sodium gluconate. The water glass is a medium-modulus water glass with an M=2.8.

[0069] The underground engineering high temperature resistant grouting water blocking material of this embodiment has an ambient temperature of 45-55°C at the water blocking point.

[0070] The melting point of low melting point hot melt adhesive is 85℃.

[0071] In this embodiment, the expansion agent, low melting point hot melt adhesive, calcium oxide and 30% of retarder in component A are prepared into retarded expansion particles for use.

[0072] The preparation method of the underground engineering high-temperature resistant grouting and water blocking material of this embodiment, the preparation method of the said component A comprises the following steps:

[0073] Prepare retarding expansion particles in advance, and stir an expansion agent, a low-melting point hot melt adhesive, calcium oxide, and a retarder with a weight ratio of 30% at 100°C to form a mixture. After the mixture cools and solidifies, it is broken into 2-5 mm particles, and the outside of the particles is covered with a 0.3 mm water-soluble polyvinyl alcohol film; the 0.3 mm water-soluble polyvinyl alcohol film is an NT-type film, and the dissolution time at room temperature is 45 minutes.

[0074] The volcanic ash gel material and water in the prescribed weight proportions are mixed and stirred evenly, and the remaining 70% of the retarder is added and continued to be mixed evenly to form slurry A;

[0075] The retarding expansion particles and slurry A are set aside separately;

[0076] The preparation method of the B component comprises the following steps:

[0077] Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 10 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B;

[0078] When using high temperature resistant grouting and water blocking materials in underground projects, component A and component B are grouted with two liquids. Before the two liquid grouting operation, the slow setting expansion particles are added to the slurry A and stirred for 3 minutes before use.

[0079] During use, the dual-liquid grouting system delivers component A and component B separately through the double-walled drill pipe. The delivery takes about 20 minutes to reach the water blocking point. At an ambient temperature between 45-55°C, components A and B initially set at the water blocking point after about one minute. The compressive strength of the stone is 1.4 MPa after one day, 5.5 MPa after three days, and 13 MPa after 10 days.

[0080] Example 4

[0081] A high-temperature resistant grouting and water-blocking material for underground engineering, comprising component A and component B. Component A is primarily composed of the following raw materials in parts by weight: 140 parts of a volcanic ash gel material, 5 parts of a retarder, 12 parts of an expansion agent, 15 parts of a low-melting-point hot-melt adhesive, 38 parts of calcium oxide, and 94 parts of water; and component B is primarily composed of the following raw materials in parts by weight: 6 parts of polyacrylamide, 7 parts of a polyacrylic acid derivative salt, 2.38 parts of an alcohol polysaccharide, 88 parts of water glass, and 45 parts of water.

[0082] Among the above raw materials, the pozzolanic gel material is a mixture of Portland cement and fly ash in a weight ratio of 1.344:4.2. The retarder is primarily composed of sodium lignin sulfonate and borax in a weight ratio of 2.6:1. The expansion agent is a mixture of cross-linked polyacrylate, sodium dodecyl sulfonate, sodium dodecyl sulfate, aluminum dodecyl sulfate, sodium α-olefin sulfonate, and aluminum powder in a weight ratio of 1:1:0.5:0.8:22:8. The low-melting-point hot-melt adhesive is an EVA hot-melt adhesive. The polyacrylic acid derivative salt is calcium polyacrylate. The alcohol polysaccharide is polyethylene glycol-2000. The water glass is a medium-modulus water glass with an M=2.6.

[0083] The ambient temperature of the underground engineering high-temperature resistant grouting water-blocking material in this embodiment is the same as that in Example 1, which is 55-60°C.

[0084] The melting point of low melting point hot melt adhesive is 80℃.

[0085] The preparation method of the underground engineering high-temperature resistant grouting and water blocking material of this embodiment, the preparation method of the said component A comprises the following steps:

[0086] Stir the expansion agent, low melting point hot melt adhesive, calcium oxide and retarder evenly to form an additive mixture;

[0087] Mixing a specified amount of volcanic ash gel material and water in parts by weight and stirring until uniformly mixed, adding the additive mixture and continuing to stir until uniformly mixed to form slurry A;

[0088] The preparation method of the B component comprises the following steps:

[0089] Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 8 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B;

[0090] When using high-temperature resistant grouting and water blocking materials in underground projects, dual-liquid grouting is used for components A and B. Components A and B are delivered separately through the double-walled drill pipe of the dual-liquid grouting system.

[0091] During the transportation process, component A experienced premature solidification of the slurry in the middle and later stages of the delivery process, leading to blockage. Grouting operations were immediately halted on-site, all relevant valves and pumping equipment were closed, and unblocking operations were performed. The cause of the blockage was analyzed to be premature reaction of the expansive agent, causing the slurry to expand, and premature reaction of calcium oxide with water to form calcium hydroxide. Initially, calcium hydroxide reduces the van der Waals forces and other attractive forces between slurry particles, reducing particle agglomeration. However, this force weakens over long-distance transportation, causing premature initial setting of slurry A.

[0092] The above-mentioned specific embodiments are only specific cases 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-mentioned specific embodiments. Any appropriate changes or modifications made to them by ordinary technicians in the relevant technical field in accordance with the claims of the present invention shall fall within the patent protection scope of the present invention.

Claims

1. A high temperature resistant grouting and water blocking material for underground engineering, characterized in that: The invention comprises component A and component B, wherein component A mainly comprises the following raw materials in parts by weight: 120-160 parts of a gel material with volcanic ash properties, 4-6 parts of a retarder, 10-15 parts of an expander, 12-18 parts of a low-melting-point hot-melt adhesive, 20-35 parts of calcium oxide, and 80-100 parts of water; and component B mainly comprises the following raw materials in parts by weight: 3-8 parts of polyacrylamide, 5-10 parts of a polyacrylic acid derivative salt, 1.25-3 parts of an alcohol polysaccharide, 50-120 parts of water glass, and 30-50 parts of water. The expander, low-melting-point hot-melt adhesive, calcium oxide, and 20-30% of the retarder in component A are prepared into retarded-setting expandable particles for use, and the preparation method comprises the following steps: Under a temperature environment above the melting point of the low-melting-point hot melt adhesive, an expansion agent, a low-melting-point hot melt adhesive, calcium oxide, and a retarder in a weight ratio of 20-30% are stirred uniformly to form a mixture. After the mixture is cooled and solidified, it is broken into 2-5 mm particles, and the outside of the particles is coated with a 0.2-0.3 mm water-soluble polyvinyl alcohol film; The low-melting-point hot-melt adhesive has a melting point higher than the ambient temperature of the grouting water blocking point and lower than the heat generation temperature of the reaction between calcium oxide and water.

2. The high-temperature resistant grouting and water-blocking material for underground engineering according to claim 1, characterized in that: The 0.2-0.3 mm water-soluble polyvinyl alcohol film is an NT-type film, and its dissolution time is 25-45 minutes in an environment of 20-35° C.

3. The high temperature resistant grouting and water blocking material for underground engineering according to claim 1, characterized in that: The water glass is a medium modulus water glass, 2.5≤M≤2.

8.

4. The high-temperature resistant grouting and water-blocking material for underground engineering according to claim 1, characterized in that: The gel material with pozzolanic properties is prepared by compounding silicate cement and fly ash in a weight ratio of (1-1.5): (3-5).

5. The high temperature resistant grouting and water blocking material for underground engineering according to claim 1, characterized in that: The retarder is mainly prepared by compounding sodium lignin sulfonate and borax in a weight ratio of (2-3):

1.

6. The high-temperature resistant grouting and water-blocking material for underground engineering according to claim 1, characterized in that: The expansion agent is mainly prepared by compounding multiple of cross-linked polyacrylate, sodium lauryl sulfonate, sodium lauryl sulfate, aluminum lauryl sulfate, sodium α-olefin sulfonate and aluminum powder.

7. The high-temperature resistant grouting and water-blocking material for underground engineering according to claim 1, characterized in that: The low melting point hot melt adhesive is one of EVA hot melt adhesive, polyester hot melt adhesive, polyester amide hot melt adhesive, polyolefin hot melt adhesive, and rubber-based hot melt adhesive.

8. The high temperature resistant grouting and water blocking material for underground engineering according to claim 1, characterized in that: The polyacrylic acid derivative salt is one of sodium polyacrylate, potassium polyacrylate, calcium polyacrylate and zinc polyacrylate.

9. The high-temperature resistant grouting and water-blocking material for underground engineering according to claim 1, characterized in that: The alcohol polysaccharide is one of polyethylene glycol-2000, sodium gluconate, sodium alginate and calendulose.

10. A method for preparing a high-temperature resistant grouting and water-blocking material for underground engineering according to any one of claims 1 to 9, characterized in that: The preparation method of the A component comprises the following steps: Pre-prepare slow-setting expansion particles; The volcanic ash gel material and water in the prescribed weight proportions are mixed and stirred evenly, and the remaining retarder is added and continued to be mixed evenly to form slurry A; The retarding expansion particles and slurry A are set aside separately; The preparation method of the B component comprises the following steps: Mix polyacrylamide, polyacrylic acid derivative salt, alcohol polysaccharide and water in specified weight parts and stir for 5-10 minutes, then add water glass in specified weight parts while mixing and continue stirring until uniform to form slurry B; When using high temperature resistant grouting and water blocking materials for underground projects, component A and component B are grouted with two liquids. Before the two liquid grouting operation, the slow setting expansion particles are added to the slurry A and stirred for 2-3 minutes before use.