A grouting material suitable for rapid sealing of water-rich formations, its preparation method and application

Abstract

This invention discloses a grouting material suitable for rapid sealing of water-rich strata, its preparation method, and its application, belonging to the field of grouting material technology. The raw materials for its preparation include component A and component B; component A, by mass parts, includes 20-80 parts cement; 10-50 parts fly ash extract; 20-60 parts water; 0.01-1 parts polycarboxylate superplasticizer; 0.025-0.05 parts polyacrylamide; 0.1-0.6 parts hydroxypropyl methylcellulose; 0.5-1 parts disodium hydrogen phosphate; and 1.5-4.5 parts calcium aluminate; component B is water glass, and the volume ratio of component A to component B is 1-5:1. The grouting material provided by this invention possesses properties such as early strength, rapid setting with adjustable setting time, good fluidity, and high water retention rate, which can meet the rapid sealing requirements of underground engineering projects such as tunnels and coal mines.

Description

Technical Field

[0001] This invention belongs to the field of grouting material technology, specifically relating to a grouting material suitable for rapid sealing of water-rich strata, its preparation method, and its application. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Underground engineering projects such as tunnels, coal mines, and subways frequently face the problem of sudden water inrushes and surges in water-rich strata during construction and operation. These water hazards not only affect construction progress but may also jeopardize the safety and stability of the project. Therefore, how to quickly and effectively seal water sources in water-rich strata has become a key technical challenge in engineering construction and maintenance. Currently, grouting sealing technology is one of the main means to deal with underground water inrushes, and its core lies in selecting appropriate grouting materials.

[0004] Traditional cement-based grouting materials have the following shortcomings: (1) Poor fluidity, making grouting construction difficult. Traditional cement-based grouting materials usually use a high water-cement ratio to improve fluidity, but this will reduce the strength of the material and make it difficult to meet the mechanical performance requirements of the sealing body in underground engineering. At the same time, high water-cement ratio grout is prone to segregation and stratification in complex strata, and problems such as pipe blockage and uneven grouting often occur during the grouting process, affecting the sealing effect and construction efficiency. (2) Insufficient early strength and rapid setting performance, making it difficult to meet the sealing requirements under dynamic water conditions. Ordinary cement-based grouting materials have a relatively long setting time and cannot quickly form and reach the required early strength in a dynamic water environment. This makes the grout easily diluted or washed away by water flow during the injection process, resulting in a significant reduction in the sealing effect. Especially in emergency situations such as water inrush in tunnels and mines, the need for rapid sealing is particularly urgent, and traditional materials are difficult to meet this requirement. (3) Low dynamic water retention rate and poor scour resistance. Under dynamic water conditions, grouting materials are easily washed away by water flow, resulting in the inability to guarantee the integrity and stability of the sealing body. This is a common challenge faced by traditional cement-based materials in dynamic water environments, directly affecting the durability and reliability of the sealing process.

[0005] Patent CN117776659A discloses a green sealing material for karst water flow, composed of component A and component B. By weight, component A includes: sulfoaluminate cement, lightly calcined magnesium oxide, boric acid, and water; component B includes: hydroxypropyl methylcellulose, polyacrylamide, potassium dihydrogen phosphate, triethanolamine, lithium carbonate, and water. It exhibits high erosion resistance, with a retention rate of up to 95% in water at a velocity of 1 m / s. It achieves ultra-short initial setting time, shortening it to 30 seconds, resulting in a paste-like grout after initial setting. The final setting time is controllable, balancing water flow resistance and long-distance grouting. However, the material's mechanical properties are not high; its 3-day compressive strength is 7 MPa, and its 28-day compressive strength is only 11.2 MPa, limiting its application range.

[0006] Therefore, there is an urgent need for a grouting material with good fluidity, early strength and rapid setting, and high water retention rate to meet the engineering requirements for rapid sealing of water-rich strata. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a grouting material suitable for rapid sealing of water-rich strata, its preparation method, and its application. The modified cement-based grouting material provided by this invention has good fluidity, early strength and rapid setting, and high dynamic water retention rate, meeting the engineering requirements for rapid sealing of water-rich strata.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows:

[0009] In a first aspect, the present invention provides a grouting material suitable for rapid sealing of water-rich formations, the raw materials for which are prepared include component A and component B;

[0010] Component A, by mass, comprises 20-80 parts cement; 10-50 parts fly ash extract; 20-60 parts water; 0.01-1 parts polycarboxylate superplasticizer; 0.025-0.05 parts polyacrylamide; 0.1-0.6 parts hydroxypropyl methylcellulose; 0.5-1 parts disodium hydrogen phosphate; and 1.5-4.5 parts calcium aluminate. Component B is water glass, and the volume ratio of component A to component B is 1-5:1.

[0011] The grouting material provided by this invention for rapid sealing of water-rich strata has properties such as early strength, rapid setting and adjustable setting time, good fluidity and high water retention rate, which can meet the rapid sealing needs of underground engineering such as tunnels and coal mines.

[0012] This invention replaces a portion of silicate cement with fly ash extract. Because the extract consists of fine spherical particles, its structure acts as a ball bearing effect in the grout, reducing frictional resistance between particles and significantly improving the grout's fluidity. While maintaining the high strength characteristics of traditional low water-cement ratio cement, the grouting material exhibits significantly improved fluidity, meeting the stringent material performance requirements of water-rich underground engineering projects and achieving an excellent balance between fluidity and strength.

[0013] This invention, based on silicate cement, fly ash extract, and water to form grouting material component A, simultaneously adds polycarboxylate superplasticizer to further improve the fluidity of the grouting material, giving it good workability and mechanical strength; adds polyacrylamide and hydroxypropyl methylcellulose to improve the injectability and erosion resistance of the grout, meeting the performance requirements of dynamic water sealing; adds calcium aluminate to cause moderate expansion of the material, further improving volume stability and sealing effect; by adjusting the amount of disodium hydrogen phosphate retarder and the volume ratio of water glass cementitious material, the setting time of the grouting material can be effectively controlled, thus adapting to the needs of different geological conditions and grouting conditions.

[0014] It should be noted that the grouting material for rapid sealing of water-rich formations provided by this invention has the characteristic of rapid setting and needs to be in a flowable state before use. Therefore, the grouting material for rapid sealing of water-rich formations needs to be prepared and used immediately, with component A and component B mixed together.

[0015] In some embodiments of the present invention, the cement is silicate cement. Optionally, the silicate cement is commercially available PO 42.5 ordinary silicate cement, wherein the total mass fraction of SiO2, Al2O3 and CaO in the cement is >90%.

[0016] In some embodiments of the present invention, the fly ash extract is ultrafine fly ash particles with a particle size of 0.2 μm-10 μm and a density of 2-3 g / cm³. 3 .

[0017] It should be noted that the term "fly ash extract" refers to a powder composed of spherical particles obtained by flotation extraction from fly ash. This extract has a relatively smooth surface and a dense internal structure, and its main components are SiO2, Al2O3, and Fe2O3. The fly ash extract is not composed of spherical particles of a single size, but rather, because it is obtained through flotation extraction, it consists of spherical particles with a particle size ranging from 0.2 μm to 10 μm.

[0018] In some embodiments of the present invention, the hydroxypropyl methylcellulose has a molecular weight of 100,000 to 200,000.

[0019] In some embodiments of the present invention, the molecular weight of the polyacrylamide is 5-7 million.

[0020] It should be noted that the molecular weights of hydroxypropyl methylcellulose and polyacrylamide in this invention have little impact on the performance of the resulting grouting material suitable for rapid sealing of water-rich formations. When the molecular weights of both are within the above-mentioned range, the resulting grouting material suitable for rapid sealing of water-rich formations exhibits excellent performance.

[0021] In some embodiments of the present invention, the water glass has a modulus of 3-3.5, a Baume degree of 18-22, and a density of 1-1.5 g / cm³. 3 .

[0022] It should be noted that the water glass mentioned is commercially available liquid water glass, such as a modulus of 3.3, a Baume degree of 20, and a density of 1.38 g / cm³. 3 Water glass.

[0023] In some embodiments of the present invention, component A, by mass parts, includes 40-60 parts of silicate cement; 10-30 parts of fly ash extract; 20-50 parts of water; 0.4-0.8 parts of polycarboxylate superplasticizer; 0.025-0.05 parts of polyacrylamide; 0.1-0.5 parts of hydroxypropyl methylcellulose; 0.5-0.7 parts of disodium hydrogen phosphate; and 1.5-2 parts of calcium aluminate.

[0024] In some embodiments of the present invention, component A, by mass parts, includes 40-50 parts of silicate cement; 10-20 parts of fly ash extract; 20-40 parts of water; 0.4-0.8 parts of polycarboxylate superplasticizer; 0.025-0.04 parts of polyacrylamide; 0.2-0.3 parts of hydroxypropyl methylcellulose; 0.5-0.6 parts of disodium hydrogen phosphate; and 1.5-2 parts of calcium aluminate.

[0025] In some embodiments of the present invention, the volume ratio of component A to component B is 1 to 5:1.

[0026] A second aspect of the present invention provides a method for preparing the above-mentioned grouting material suitable for rapid sealing of water-rich formations, comprising:

[0027] Silicate cement, fly ash extract, water, polycarboxylate superplasticizer, polyacrylamide, hydroxypropyl methylcellulose, disodium hydrogen phosphate and calcium aluminate are mixed to obtain component A slurry;

[0028] The A component slurry is mixed with water glass to obtain a grouting material suitable for rapid sealing of water-rich formations.

[0029] It should be noted that the grouting material for rapid sealing of water-rich formations provided by this invention has the characteristic of rapid setting and needs to be in a flowable state before use. Therefore, the grouting material for rapid sealing of water-rich formations needs to be prepared and used immediately, and components A and B should be mixed before use.

[0030] A third aspect of the present invention provides the application of the above-mentioned grouting material suitable for rapid sealing of water-rich strata or the grouting material prepared by the above-mentioned preparation method suitable for rapid sealing of water-rich strata in the sealing of sudden water inrush in underground engineering.

[0031] A fourth aspect of the present invention provides a method for sealing sudden water inrush in underground engineering, comprising the following steps: mixing component A and component B and then performing pressure grouting on the outlet and its surroundings until there is no seepage or water inrush within three minutes after sealing the outlet; the injected grout is the above-mentioned grouting material suitable for rapid sealing of water-rich strata or the grouting material prepared by the above-mentioned preparation method suitable for rapid sealing of water-rich strata.

[0032] The beneficial effects of this invention are as follows:

[0033] Compared with existing technologies, the grouting material for rapid sealing of water-rich strata provided by this invention fully utilizes fly ash extract from industrial waste, achieving resource reuse. Furthermore, by employing specific component compositions with good interactions between the components, the grouting material for rapid sealing of water-rich strata exhibits properties such as early strength, rapid setting with adjustable setting time, good fluidity, and high water retention rate, meeting the rapid sealing requirements of underground engineering projects such as tunnels and coal mines. Experimental results show that component A of the grouting material for rapid sealing of water-rich strata provided by this invention has a flow time as low as 5.19s, an initial setting time reduced to 16.5s, a 3-day compressive strength as high as 25.3MPa, and a retention rate of up to 93% in water velocities of 0.8-1m / s.

[0034] The parameters in the preparation process of the grouting material for rapid sealing of water-rich strata provided by this invention are easy to control, the process is simple, and it is easy to promote and apply on a large scale. Attached Figure Description

[0035] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0036] Figure 1 This is a composition diagram of the grouting material prepared in Example 1 of the present invention, suitable for rapid sealing of water-rich formations. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0038] The silicate cement used in the following examples and comparative examples is PO 42.5 ordinary silicate cement, and the fly ash extract is ultrafine fly ash particles with a particle size of 0.2μm-10μm and a density of 2-3g / cm³. 3 Water glass has a modulus of 3.3, a Baumé degree of 20, and a density of 1.38 g / cm³. 3 The molecular weight of polyacrylamide is 6 million. The molecular weight of hydroxypropyl methylcellulose is 150,000.

[0039] Example 1

[0040] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0041] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 20 parts of fly ash extract, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.025 parts of polyacrylamide, 0.2 parts of hydroxypropyl methylcellulose, 2 parts of calcium aluminate, and 0.6 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0042] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0043] Example 2

[0044] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0045] (1) Preparation of component A slurry: Take 50 parts by weight of silicate cement, 10 parts of fly ash extract, 30 parts of water, 0.6 parts of polycarboxylate superplasticizer, 0.025 parts of polyacrylamide, 0.2 parts of hydroxypropyl methylcellulose, 1.5 parts of calcium aluminate and 0.5 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0046] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0047] Example 3

[0048] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0049] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 10 parts of fly ash extract, 20 parts of water, 0.8 parts of polycarboxylate superplasticizer, 0.04 parts of polyacrylamide, 0.3 parts of hydroxypropyl methylcellulose, 2 parts of calcium aluminate, and 0.5 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0050] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0051] Comparative Example 1

[0052] A modified cement-based grouting material suitable for rapid sealing of water-rich formations includes the following steps:

[0053] (1) Preparation of component A slurry: Take 60 parts by weight of silicate cement, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.025 parts of polyacrylamide, 0.2 parts of hydroxypropyl methylcellulose, 2 parts of calcium aluminate, and 0.6 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0054] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0055] Comparative Example 2

[0056] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0057] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 20 parts of fly ash extract, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.225 parts of hydroxypropyl methylcellulose, 2 parts of calcium aluminate, and 0.6 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0058] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0059] Comparative Example 3

[0060] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0061] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 20 parts of fly ash extract, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.225 parts of polyacrylamide, 2 parts of calcium aluminate, and 0.6 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0062] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0063] Comparative Example 4

[0064] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0065] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 20 parts of fly ash extract, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.025 parts of polyacrylamide, 0.2 parts of hydroxypropyl methylcellulose, and 0.6 parts of disodium hydrogen phosphate, mix them and stir evenly to obtain component A slurry.

[0066] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0067] Comparative Example 5

[0068] A modified cement-based grouting material suitable for rapid sealing of water-rich formations, the preparation method of which includes the following steps:

[0069] (1) Preparation of component A slurry: Take 40 parts by weight of silicate cement, 20 parts of fly ash extract, 25 parts of water, 0.4 parts of polycarboxylate superplasticizer, 0.025 parts of polyacrylamide, 0.2 parts of hydroxypropyl methylcellulose, and 2 parts of calcium aluminate, mix them and stir evenly to obtain component A slurry.

[0070] (2) Mix component A slurry and component B (water glass) in a volume ratio of 2:1 thoroughly to obtain modified cement-based grouting material, which can then be used for grouting.

[0071] Experimental Example 1

[0072] The performance of the modified cement-based grouting materials prepared in the examples and comparative examples was tested using the following methods:

[0073] The flow time of the obtained component A slurry was measured using a Cotton 6 cup: Component A slurry was poured into a Cotton 6 cup, ensuring the liquid level was flush with the top edge of the cup. The valve at the bottom orifice of the Cotton 6 cup was quickly opened, allowing the slurry to flow out through the hole at the bottom. A stopwatch was started simultaneously, and the stopwatch was stopped immediately at the moment the slurry flowed completely out of the Cotton 6 cup. The total flow time was recorded. Each set was repeated three times, and the average value was taken to verify its flowability.

[0074] The obtained grouting material was subjected to initial setting test, specimen preparation, compressive strength test, and erosion resistance test.

[0075] Pour the obtained component A slurry and water glass into two beakers according to the specified volume ratio. Then pour the component A slurry into the beaker containing water glass, and immediately pour the mixture into the other beaker. Repeat the alternating mixing until the slurry can no longer be poured or its flow is obviously blocked. Record the time when the slurry is stopped. This is the initial setting time. Repeat each group 3 times and take the average value as the final result.

[0076] The obtained modified cement-based grouting material was poured into a 40mm×40mm×40mm cube mold for specimen preparation. After the modified cement-based grouting material was prepared into standard 40mm×40mm×40mm cubes and cured for 3 days, indoor uniaxial compression tests were conducted to obtain the compressive strength. Each group was repeated 3 times and the average value was taken as the final result.

[0077] The modified cement-based grouting material was poured onto the test device and flushed with dynamic water at a flow rate of 0.8 m / s to 1.0 m / s for a certain period of time (more than 3 minutes). The change in grout mass before and after was measured to obtain the dynamic water retention rate, which was used to evaluate the erosion resistance.

[0078] The performance of the modified cement-based grouting materials obtained in the examples and comparative examples is shown in Table 1.

[0079] Table 1. Performance of modified cement-based grouting materials obtained in the examples and comparative examples.

[0080]

[0081] Table 1 shows that fly ash extract affects the flow time of component A and the retention rate of dynamic water. Partially replacing cement with fly ash extract improves the fluidity of the grout, ensuring that the grouting material maintains the high strength characteristics of traditional low water-cement ratio cement while significantly improving its fluidity. This meets the stringent requirements for material performance in water-rich underground engineering, achieving an excellent balance between fluidity and strength. Adding polyacrylamide and hydroxypropyl methylcellulose improves the injectability and erosion resistance of the grout, reduces the initial setting time, and meets the performance requirements for dynamic water sealing. Adding calcium aluminate causes moderate expansion of the material, further improving volume stability and sealing effect. Adding disodium hydrogen phosphate retarder effectively controls the setting time of the grouting material, thus adapting to the needs of different geological conditions and grouting processes.

[0082] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A grouting material suitable for rapid sealing of water-rich formations, characterized in that, Its preparation materials include component A and component B; Component A, by mass, comprises 20-80 parts cement; 10-50 parts fly ash extract; 20-60 parts water; 0.01-1 parts polycarboxylate superplasticizer; 0.025-0.05 parts polyacrylamide; 0.1-0.6 parts hydroxypropyl methylcellulose; 0.5-1 parts disodium hydrogen phosphate; and 1.5-4.5 parts calcium aluminate. Component B is water glass, and the volume ratio of component A to component B is 1-5:

1. The fly ash extract is a powder composed of spherical particles obtained by flotation from fly ash, consisting of spherical particles with a particle size in the range of 0.2 μm to 10 μm.

2. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, The cement is silicate cement; The fly ash extract has a particle size of 0.2 μm-10 μm and a density of 2-3 g / cm³. 3 .

3. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, The hydroxypropyl methylcellulose has a molecular weight of 100,000 to 200,000. The polyacrylamide has a molecular weight of 5-7 million.

4. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, The water glass has a modulus of 3-3.5, a Baume degree of 18-22, and a density of 1-1.5 g / cm³. 3 .

5. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, Component A, by mass parts, includes 40-60 parts of silicate cement; 10-30 parts of fly ash extract; 20-50 parts of water; 0.4-0.8 parts of polycarboxylate superplasticizer; 0.025-0.05 parts of polyacrylamide; 0.1-0.5 parts of hydroxypropyl methylcellulose; 0.5-0.7 parts of disodium hydrogen phosphate; and 1.5-2 parts of calcium aluminate.

6. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, Component A, by mass, comprises 40-50 parts silicate cement; 10-20 parts fly ash extract; 20-40 parts water; 0.4-0.8 parts polycarboxylate superplasticizer; 0.025-0.04 parts polyacrylamide; 0.2-0.3 parts hydroxypropyl methylcellulose; 0.5-0.6 parts disodium hydrogen phosphate; and 1.5-2 parts calcium aluminate.

7. The grouting material for rapid sealing of water-rich strata as described in claim 1, characterized in that, The volume ratio of component A to component B is 2:

1.

8. A method for preparing a grouting material suitable for rapid sealing of water-rich strata as described in any one of claims 1-7, characterized in that, include: Cement, fly ash extract, water, polycarboxylate superplasticizer, polyacrylamide, hydroxypropyl methylcellulose, disodium hydrogen phosphate and calcium aluminate are mixed to obtain component A slurry; The A component slurry is mixed with water glass to obtain a grouting material suitable for rapid sealing of water-rich formations.

9. The application of a grouting material suitable for rapid sealing of water-rich strata as described in any one of claims 1-7, or a grouting material suitable for rapid sealing of water-rich strata prepared by the preparation method described in claim 8, in the sealing of sudden water inrush in underground engineering.

10. A method for sealing sudden water inrushes in underground engineering projects, characterized in that, The process includes the following steps: mixing component A and component B and then applying pressure grouting to the outlet and its surroundings until there is no seepage or gushing water within three minutes after the outlet is sealed. The injected grout is the grouting material suitable for rapid sealing of water-rich strata as described in any one of claims 1-7 or the grouting material suitable for rapid sealing of water-rich strata prepared by the preparation method described in claim 8.

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