Underwater self-repairing non-dispersing agent and large-flow water seepage plugging composite grouting material

Abstract

The invention discloses an underwater self-repairing non-dispersing agent and a high-flow water seepage plugging composite grouting material. The underwater self-repairing non-dispersing agent is prepared from the following raw material components in percentage by mass: 5 to 10 percent of caesalpinia spinosa gum, 3 to 7 percent of nano-hydroxyapatite, 2 to 5 percent of chitosan quaternary ammonium salt, 10 to 20 percent of calcium sulphoaluminate, 5 to 12 percent of magnesium oxide, 0.5 to 2 percent of graphene oxide, 7 to 15 percent of bentonite and 40 to 65 percent of deionized water. The underwater self-repairing non-dispersing agent provided by the invention has high dispersion resistance and a self-repairing function, takes natural macromolecules and inorganic minerals as main raw materials, is free of toxic components, meets the environmental protection requirements of underground engineering, has stable performance in a pH value range of 3-11, adapts to underground complex water quality environments, has good compatibility with components such as hydrophilic polyurethane and Portland cement, and can be widely applied to the field of underground engineering. The gelation time of the slurry is not interfered, and the bonding strength of the composite grouting material can be effectively improved, so that the durability of the underwater repair of the material is improved.

Description

Technical Field

[0001] This invention belongs to the field of organic polymer compound technology, specifically relating to an underwater self-healing non-dispersible agent and a high-flow-rate seepage-stopping composite grouting material. Background Technology

[0002] With the rapid advancement of urbanization in my country, the development of rail transit and underground space is expanding in depth, leading to increasingly prominent issues of water leakage in underground structures. Leakage not only deteriorates the internal environment of buildings but also reduces structural durability, affects functionality and aesthetics, and threatens building safety and usability. Conventional grouting sealing techniques can effectively address minor leaks; however, in underground engineering, leakage control in environments with high-flow-rate water presents unique challenges—the dilution and scouring effect of water flow alters the water-cement ratio of the grout, leading to performance degradation and even flushing the grout out of the treatment area. Therefore, developing grouting materials with excellent anti-dispersion and anti-erosion properties has become a key technical challenge to ensure effective grouting in dynamic water environments. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art by providing an underwater self-healing non-dispersant agent and a high-flow-rate seepage-stopping composite grout. The underwater self-healing non-dispersant agent has high anti-dispersion properties, high dynamic water retention rate, and self-repair function. The high-flow-rate seepage-stopping composite grout prepared based on the non-dispersant agent can quickly seal high-flow-rate seepage and effectively solve the problem of high-flow-rate water leakage in underground concrete.

[0004] The first aspect of this invention provides an underwater self-healing non-dispersible agent, the raw material components and mass percentages of which are as follows: 5-10% of strychnine gelatin, 3-7% of nano-hydroxyapatite, 2-5% of chitosan quaternary ammonium salt, 10-20% of calcium sulfoaluminate, 5-12% of magnesium oxide, 0.5-2% of graphene oxide, 7-15% of bentonite, and 40-65% of deionized water.

[0005] According to the above scheme, the particle size of the nano-hydroxyapatite is 20-40nm and the purity is ≥99wt%.

[0006] According to the above scheme, the calcium sulfoaluminate is high-purity calcium sulfoaluminate with a purity ≥ 99 wt%.

[0007] According to the above scheme, the magnesium oxide particle size is 30-50nm and the purity is ≥99.9wt%.

[0008] According to the above scheme, the graphene oxide has a sheet diameter of 15-30 μm and a thickness of 8-20 nm.

[0009] According to the above scheme, the bentonite is sodium-based bentonite with a particle size of 30-80 μm.

[0010] Preferably, the mass ratio of the sclerotium spores to calcium sulfoaluminate is 1:1.8-2.2. This ratio effectively balances anti-dispersion properties and strength development. The viscous nature of the sclerotium spores forms a network structure to prevent slurry dispersion, while the hydration of calcium sulfoaluminate produces ettringite, enhancing strength. At this ratio, the two work synergistically, ensuring both anti-dispersion effectiveness and strength growth.

[0011] Preferably, the mass ratio of nano-hydroxyapatite to graphene oxide is 3.5-5:1. Nano-hydroxyapatite and graphene oxide can effectively enhance self-healing ability and structural stability, and this ratio can maximize mineralization repair efficiency and structural support.

[0012] Preferably, the mass ratio of magnesium oxide to bentonite is 1:1.2-1.5. Using magnesium oxide and bentonite in this ratio avoids excessive expansion or insufficient viscosity, ensuring repair effectiveness and workability, and optimizing expansion filling and system stability.

[0013] Preferably, the ratio of the total mass of the prickly pear colloid and chitosan quaternary ammonium salt to the total mass of calcium sulfoaluminate and magnesium oxide is 1:2-2.5. The former focuses on anti-dispersion, while the latter focuses on self-healing and strength. This ratio allows the two core functions to work synergistically, improving overall performance.

[0014] The second aspect of this invention provides a method for preparing the above-mentioned underwater self-healing non-dispersible agent, the specific steps of which are as follows: the nano-hydroxyapatite and graphene oxide are added to deionized water, and ultrasonically dispersed to obtain a nano-dispersion with active groups. Then, under heating conditions, argan oil, chitosan quaternary ammonium salt and bentonite are added and stirred at high speed until uniform. Then, the mixture is cooled to room temperature, and calcium sulfoaluminate and magnesium oxide are added and stirred at low speed until uniform. Finally, the mixture is vacuum dried, pulverized and sieved to obtain a powdered finished product.

[0015] According to the above scheme, the ultrasonic dispersion treatment time is 20-30 minutes.

[0016] According to the above plan, the heating temperature is 60-70℃.

[0017] According to the above scheme, the high-speed stirring speed is 800-1000 rpm, and the stirring time is 30-40 min.

[0018] According to the above scheme, the low-speed stirring speed is 300-500 rpm, and the stirring time is 10-20 min.

[0019] According to the above scheme, the vacuum drying temperature is 40-50℃ and the drying time is 10-12h.

[0020] According to the above scheme, the sieve should be passed through an 80-120 mesh screen.

[0021] The third aspect of this invention provides a high-flow-rate seepage-stopping composite grouting material prepared according to the above-mentioned underwater self-healing non-dispersant agent, wherein the raw materials and their mass proportions are as follows: 100-120 parts of hydrophilic polyurethane, 50-60 parts of silicate cement, 5-8 parts of internal curing material, 3-5 parts of organophosphonic acid compound, 1-2 parts of sodium silicate, 5-8 parts of fumed silica, 10-15 parts of 40-80 mesh fine sand, 10-15 parts of 80-120 mesh fine sand, 2-3 parts of underwater self-healing non-dispersant agent, and 2-4 parts of ethylene acrylic acid copolymer.

[0022] According to the above scheme, the viscosity of the hydrophilic polyurethane is ≤600 mPa·s, and the gel time is ≤60 s.

[0023] According to the above scheme, the silicate cement is ordinary silicate cement with a strength grade of 42.5 or higher.

[0024] According to the above scheme, the organophosphonic acid compound is aminotrimethylenephosphonic acid or hydroxyethylidene diphosphonic acid. This component acts as a system stabilizer, chelating Ca in groundwater. 2+ Fe 3+ The presence of metal ions helps prevent harmful reactions, improves the interfacial affinity between the grout and the concrete matrix, and enhances long-term durability.

[0025] According to the above scheme, the sodium silicate is powdered sodium silicate with a silicon dioxide content of 52.0-56.0 wt% and a particle size ≤60 μm.

[0026] According to the above scheme, the fumed silica is hydrophilic fumed silica with a specific surface area of ​​300-500 m². 2 / g, with a particle size of 10-30nm. Its function is to increase the viscosity and stability of the slurry, improve the strength and impermeability of the solidified body, and enhance pumpability.

[0027] According to the above scheme, the acrylic acid content in the ethylene-acrylic acid copolymer is 8-10 wt%. This component can effectively fill the pores of the non-dispersant network, improve the density of the slurry structure, and form hydrogen bonds with chitosan quaternary ammonium salt to enhance the interfacial bonding between the organic and inorganic phases, shorten the gelation time, and improve the curing efficiency.

[0028] According to the above scheme, the mass ratio of the hydrophilic polyurethane to the total mass of silicate cement, 40-80 mesh fine sand, and 80-120 mesh fine sand is 1.3-1.5:1. At this ratio, a rapid sealing effect can be guaranteed, the hydrophilic polyurethane quickly gels, and synergistically forms a high-strength solidified body with other components. Simultaneously, the system stability is improved; at this ratio, the slurry viscosity is moderate, its pumpability is strong, and the bonding strength with the concrete matrix is ​​ensured.

[0029] The fourth aspect of this invention provides a method for preparing the above-mentioned high-flow-rate seepage-stopping composite grouting material, the specific steps of which are as follows: 1) Weigh the raw materials according to the proportions and set aside; 2) Mix silicate cement, internal curing material, organophosphonic acid compound, sodium silicate, fumed silica, 40-80 mesh fine sand, 80-120 mesh fine sand and underwater self-healing non-dispersant agent evenly to obtain mixed component A; 3) Slowly add the mixed component A obtained in step 1) to the hydrophilic polyurethane and stir evenly with a high-speed mixer to obtain mixed component B; 4) Slowly heat the ethylene-acrylic acid copolymer until it becomes completely liquid, then add it to the mixed component B obtained in step 3). Stir evenly using a high-speed mixer to obtain a high-flow-rate seepage-stopping composite grout.

[0030] According to the above scheme, the mixing conditions for step 3) of the high-speed mixer are: mixing at a speed of 800-1000 r / min for 3-5 minutes.

[0031] According to the above scheme, step 4) involves slowly heating the ethylene-acrylic acid copolymer under the following conditions: heating at a rate of 5℃ / min to 180-200℃. Slow heating is used to prevent the ethylene-acrylic acid copolymer from decomposing due to localized overheating, ensuring uniform melting and stable performance.

[0032] According to the above scheme, the mixing conditions for step 4) of the high-speed mixer are: mix at a speed of 1500-1800 r / min for 5-7 min.

[0033] The fifth aspect of this invention provides the application of the above-mentioned underwater self-healing non-dispersible agent and high-flow-rate seepage-stopping composite grout in the field of concrete.

[0034] The underwater self-healing non-dispersible agent provided by this invention forms a stable system with organic components (silica gel, chitosan quaternary ammonium salt) and inorganic components (calcium sulfoaluminate, magnesium oxide, etc.). The organic components provide an anti-dispersion network, while the inorganic components provide strength and repair capabilities. Nano-hydroxyapatite and graphene oxide synergistically enhance the repair effect and structural stability, while magnesium oxide and bentonite synergistically optimize expansion and filling and system viscosity. The viscous network structure formed by silica gel and bentonite prevents the grout from being washed away and dispersed by water flow. The stable system formed by the synergistic effect of each component is not easily diluted under dynamic water conditions, thus improving the retention rate. It has high anti-dispersion properties and can effectively improve the dynamic water retention rate of composite grouting material at a dynamic water flow rate of 0.5 m / s. It also has a self-healing function. During use, through the hydration of calcium sulfoaluminate to generate ettringite, the expansion and filling of magnesium oxide, and the mineralization effect of nano-hydroxyapatite, it can self-repair micro-cracks with a width of 0.5-1.0 mm. The compressive strength retention rate after 28 days is ≥85%.

[0035] A high-flow-rate seepage-stopping composite grout was prepared using the aforementioned underwater self-healing non-dispersant. This underwater self-healing non-dispersant exhibits good compatibility with components such as hydrophilic polyurethane and silicate cement, does not interfere with the grout gelation time, and effectively improves the bonding strength of the composite material, thereby enhancing the durability of the underwater repair. The addition of internal curing materials enhances the gelation time of the hydrophilic polyurethane, while the underwater self-healing non-dispersant effectively improves the material retention rate of the grout under high-flow-rate leakage conditions. Aggregates of different particle sizes not only increase the density of the grout but also better enhance the strength and compactness of the grout consolidation. Small molecule materials such as organophosphonic acid compounds act as system stabilizers, chelating Ca in groundwater. 2+ Fe 3+ The presence of metal ions prevents harmful reactions (such as premature flocculation and strength degradation) with active groups in the grout, while simultaneously improving the interfacial affinity between the grout and the concrete matrix, reducing interfacial delamination caused by ion migration, thereby enhancing the long-term durability of the composite grout. This addresses the shortcomings of polyurethane grouting materials, such as poor durability and easy detachment from the matrix. The high-flow-rate seepage sealing composite grout prepared based on this underwater self-healing non-dispersant agent can quickly seal large-flow-rate seepage, with gelation speed and retention rate adapted to engineering requirements; it boasts high strength and good durability, and its self-healing function improves upon the problems of easy detachment and short lifespan of traditional materials.

[0036] The beneficial effects of this invention are as follows: 1. The underwater self-healing non-dispersant provided by this invention has high anti-dispersion and self-healing functions. It uses natural polymers and inorganic minerals as main raw materials, contains no toxic components, meets the environmental protection requirements of underground engineering, maintains stable performance within a pH range of 3-11, adapts to complex underground water environments, has good compatibility with hydrophilic polyurethane, silicate cement, and other components, does not interfere with the gel time of the grout, and can effectively improve the bonding strength of the composite grout, thereby improving the durability of the underwater repair material. 2. The high-flow-rate seepage plugging composite grout prepared based on the underwater self-healing non-dispersant can quickly seal large-flow-rate seepage. The gel speed and retention rate are adapted to engineering needs, with high strength and good durability. The self-healing function improves the problems of easy detachment and short lifespan of traditional materials. The grout viscosity is moderate, with strong pumpability, adaptable to high-pressure grouting processes. The components are environmentally friendly, with no release of volatile harmful substances, meeting relevant specifications and effectively solving the problem of large-flow-rate seepage in underground concrete. 3. The preparation method of the underwater self-healing non-dispersant agent and high-flow-rate seepage plugging composite grout of the present invention is mild, simple in steps, easy to industrialize, and has the advantages of readily available raw materials, controllable cost, strong process compatibility, easy-to-control reaction and high stability, outstanding environmental protection and strong scalability. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the test apparatus for the resistance to dynamic water dispersion of the present invention; Figure 2 Photographs of the bonding strength samples of the high-flow-rate seepage-stopping composite grouting materials prepared in Examples 1-3 and Comparative Examples 1-3. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] The nano-hydroxyapatite used in the embodiments and comparative examples of this invention has a particle size of 20-40 nm and a purity ≥99 wt%; the magnesium oxide used has a particle size of 30-50 nm and a purity ≥99.9 wt%; the calcium sulfoaluminate used has a purity ≥99 wt%; the graphene oxide used is purchased from Jiangxi Shuobang New Material Technology Co., Ltd., with a sheet diameter of 15-30 μm and a thickness of 8-20 nm; the bentonite used is sodium-based bentonite with a particle size of 30-80 μm; the internal curing material used is SY-P concrete internal curing agent produced by Wuhan Sanyuan Special Building Materials Co., Ltd.; and the ethylene-acrylic acid copolymer used is Dow EAA (American company). 3002, with an acrylic acid content of 8-10 wt%; the hydrophilic polyurethane used is a water-soluble polyurethane grouting material produced by Nantong Yuru Engineering Materials Co., Ltd., with a viscosity of 546 mPa·s and a gel time of 60 s; the silicate cement used is ordinary silicate cement with a strength grade of 42.5; the sodium silicate used is powdered sodium silicate with a silica content of 52.0-56.0 wt% and a particle size ≤60 μm; the fumed silica used is hydrophilic fumed silica HL-380 from Hubei Huifu Nanomaterials Co., Ltd., with a specific surface area of ​​300-500 m² / g and a particle size of 10-30 nm.

[0040] Unless otherwise specified, the term "parts" mentioned in the embodiments and comparative examples of this invention generally refers to parts by mass.

[0041] Example 1 An underwater self-healing non-dispersible agent is prepared as follows: 6 parts of nano-hydroxyapatite and 1.5 parts of graphene oxide are added to 65 parts of deionized water and ultrasonically dispersed for 25 min to obtain a uniformly dispersed nano-dispersion. The obtained nano-dispersion is heated to 65℃, and 9 parts of argan oil, 4 parts of chitosan quaternary ammonium salt and 12 parts of bentonite are added. The mixture is stirred at 900 rpm for 35 min, cooled to room temperature, and then 18 parts of calcium sulfoaluminate and 10 parts of magnesium oxide are added. The mixture is stirred at 400 rpm for 15 min to ensure uniform dispersion. Finally, the mixture is vacuum dried at 45℃ for 11 h, pulverized and passed through a 100-mesh sieve to obtain a powdered underwater self-healing non-dispersible agent.

[0042] A high-flow-rate composite grouting material for seepage sealing and plugging was prepared using the aforementioned underwater self-healing non-dispersant agent. The specific preparation method is as follows: 1) Mix 60 parts silicate cement, 5 parts internal curing material, 3 parts aminotrimethylene phosphonic acid, 2 parts sodium silicate, 5 parts fumed silica, 10 parts 40-80 mesh fine sand, 12 parts 80-120 mesh fine sand and 2 parts underwater self-healing non-dispersant agent until uniformly stirred to obtain mixed component A. 2) Slowly add mixed component A to 110 parts of hydrophilic polyurethane, and stir with a high-speed mixer at 900 r / min for 4 min to obtain mixed component B; 3) Slowly heat 2 parts of ethylene-acrylic acid copolymer to 200°C at a rate of 5°C / min. After the ethylene-acrylic acid copolymer has completely turned into a liquid, add it to the mixed component B. Stir with a high-speed mixer at a speed of 1700r / min for 6 minutes to obtain a high-flow-rate seepage-stopping composite grout.

[0043] Example 2 An underwater self-healing non-dispersible agent is prepared as follows: 5 parts of nano-hydroxyapatite and 1 part of graphene oxide are added to 60 parts of deionized water and ultrasonically dispersed for 20 min to obtain a uniformly dispersed nano-dispersion. The obtained nano-dispersion is heated to 60℃, and 8 parts of argan oil, 3 parts of chitosan quaternary ammonium salt and 10 parts of bentonite are added. The mixture is stirred at 800 rpm for 30 min, cooled to room temperature, and 15 parts of calcium sulfoaluminate and 8 parts of magnesium oxide are added. The mixture is stirred at 300 rpm for 10 min to ensure uniform dispersion. Finally, the mixture is vacuum dried at 40℃ for 10 h, pulverized and passed through an 80-mesh sieve to obtain a powdered underwater self-healing non-dispersible agent.

[0044] A high-flow-rate composite grouting material for seepage sealing and plugging was prepared using the aforementioned underwater self-healing non-dispersant agent. The specific preparation method is as follows: 1) Mix 50 parts silicate cement, 8 parts internal curing material, 5 parts aminotrimethylene phosphonic acid, 1 part sodium silicate, 6 parts fumed silica, 12 parts 40-80 mesh fine sand, 13 parts 80-120 mesh fine sand and 3 parts underwater self-healing non-dispersant agent until uniformly stirred to obtain mixed component A. 2) Slowly add mixed component A to 100 parts of hydrophilic polyurethane, and stir for 5 minutes at 1000 r / min using a high-speed mixer to obtain mixed component B; 3) Slowly heat 4 parts of ethylene-acrylic acid copolymer to 180°C at a rate of 5°C / min. After the ethylene-acrylic acid copolymer has completely turned into liquid, add it to the mixed component B. Stir with a high-speed mixer at a speed of 1800r / min for 5min to obtain a high-flow-rate seepage-stopping composite grout.

[0045] Example 3 A self-healing underwater non-dispersible agent is prepared as follows: 7 parts of nano-hydroxyapatite and 2 parts of graphene oxide are added to 70 parts of deionized water and ultrasonically dispersed for 30 min to obtain a uniformly dispersed nano-dispersion. The obtained nano-dispersion is heated to 70℃, and 10 parts of argan oil, 5 parts of chitosan quaternary ammonium salt and 15 parts of bentonite are added. The mixture is stirred at 1000 rpm for 30 min, cooled to room temperature, and 20 parts of calcium sulfoaluminate and 12 parts of magnesium oxide are added. The mixture is stirred at 500 rpm for 10 min to ensure uniform dispersion. Finally, the mixture is vacuum dried at 50℃ for 10 h, pulverized and passed through a 120-mesh sieve to obtain a powdered self-healing underwater non-dispersible agent.

[0046] A high-flow-rate composite grouting material for seepage sealing and plugging was prepared using the aforementioned underwater self-healing non-dispersant agent. The specific preparation method is as follows: 1) Mix 55 parts silicate cement, 8 parts internal curing material, 5 parts aminotrimethylene phosphonic acid, 2 parts sodium silicate, 7 parts fumed silica, 15 parts 40-80 mesh fine sand, 10 parts 80-120 mesh fine sand and 2 parts underwater self-healing non-dispersant agent until uniformly stirred to obtain mixed component A. 2) Slowly add mixed component A to 110 parts of hydrophilic polyurethane and stir for 4 minutes at 800 r / min using a high-speed mixer to obtain mixed component B; 3) Slowly heat 3 parts of ethylene-acrylic acid copolymer to 180°C at a rate of 5°C / min. After the ethylene-acrylic acid copolymer has completely turned into liquid, add it to the mixed component B. Stir with a high-speed mixer at a speed of 1500r / min for 7min to obtain a high-flow-rate seepage-stopping composite grout.

[0047] Comparative Example 1 A high-flow-rate seepage-stopping composite grouting material is prepared in a way that differs from that in Example 1 in that it does not contain an underwater self-healing non-dispersant.

[0048] Comparative Example 2 A high-flow-rate seepage-stopping composite grouting material is prepared differently from that in Example 1 in that it does not contain ethylene-acrylic acid copolymer.

[0049] Comparative Example 3 A high-flow-rate seepage-stopping composite grouting material, the preparation method of which differs from that of Example 1, is as follows: the amount of 40-80 mesh fine sand added is 16 parts, and the amount of 80-120 mesh fine sand added is 6 parts.

[0050] The specific formulations of Examples 1-3 and Comparative Examples 1-3 are shown in Table 1.

[0051] Table 1

[0052] The gel time of the high-flow-rate seepage-stopping composite grouting materials prepared in Examples 1-3 and Comparative Examples 1-3 was tested according to the standard "JC / T 2041-2020 Polyurethane Grouting Materials".

[0053] Flow retention rate test: passed Figure 1 The test apparatus for resisting the dispersion of dynamic water shown was used to test the resistance of the composite grouting materials prepared in Examples 1-3 and Comparative Examples 1-3 to dynamic water erosion. The test method was based on [Zeng Laiheng, Zhang Xi, Hu Tieqiao, et al. Composite polyurethane cement mortar for large flow seepage plugging [J]. Water Resources and Hydropower Engineering (Chinese and English), 2023, 54(2):170-178.]. The dynamic water flow rate was controlled at 0.5 m / s, the grouting speed was 0.1 m / s, and the grouting volume was 2 L each time. When the liquid flowing out of the outlet was basically clear water, the water pump was turned off, the gel deposited in the water tank was collected and weighed, and the grout retention rate was the ratio of the mass of the grout gel deposited in the water tank under dynamic water conditions to the mass of the injected grout.

[0054] The bonding strength of the high-flow-rate seepage-stopping composite grouting materials prepared in Examples 1-3 and Comparative Examples 1-3 was tested according to the standard "DL / T 5785-2019 Test Procedure for Chemical Grouting Materials for Water Conservancy and Hydropower Engineering". The 60-day dry bonding strength test method involved placing the prepared samples in an oven at 35-40℃ for 60 days and measuring the bonding strength thereafter. The 60-day wet bonding strength test method involved placing the prepared samples in deionized water for 60 days and measuring the bonding strength thereafter. The 60-day alkaline bonding strength test method involved placing the prepared samples in a sodium hydroxide solution with a pH of 11-12 for 60 days and measuring the bonding strength thereafter. Figure 2 The image shown is a photograph of a sample used in the adhesive strength test.

[0055] The repair coefficient of the composite grouting materials prepared in Examples 1-3 and Comparative Examples 1-3 for 0.3mm wide cracks was tested according to the method in "T / SZWA 003-2020 Technical Specification for Self-Healing Waterproofing Materials Admixtured in Concrete".

[0056] The test results of Examples 1-3 and Comparative Examples 1-3 are shown in Table 2 below.

[0057] Table 2

[0058] As shown in Table 2, the high-flow-rate seepage-stopping composite grout prepared in the embodiments of the present invention exhibits high retention rate in flowing water, high bonding strength with the concrete substrate, rapid gelation speed, good sealing effect, and excellent durability. In contrast, Comparative Example 1, without the addition of an underwater self-healing non-dispersant, shows a significant deterioration in performance compared to the embodiments, especially a substantial reduction in self-healing effect. Under flowing water conditions, due to the lack of a three-dimensional network framework formed by the underwater self-healing non-dispersant, the grout is unable to resist water erosion, resulting in a significant decrease in retention rate. It fails to form an effective sealing layer at the leak point, and the bonding strength with the concrete substrate is significantly reduced. Regardless of whether it is dry, wet, or alkaline, the interfacial bonding force is significantly weakened, making it prone to peeling and detachment due to water flow disturbance during long-term use. The grout is dispersed by water flow before full curing, further weakening the sealing effect. Test results indicate that the underwater self-healing non-dispersant is the core component for improving the grout's anti-dispersion properties, interfacial adhesion, and curing coordination. Through the synergistic effect of natural polymers and inorganic minerals, it provides the grout with an anti-loss foundation and interfacial affinity. Comparative Example 2, without the addition of ethylene-acrylic acid copolymer (EAA), showed a significant performance difference compared to the Example 1. Its dynamic water retention rate was lower than the Example 1. This was due to the lack of EAA's filling effect on the pores of the dispersant network after melting, resulting in insufficient density of the slurry structure and making it susceptible to erosion by water flow, leading to the loss of some particles. The dry bond strength with concrete decreased significantly. Due to the absence of the synergistic hydrogen bonding between EAA and the chitosan quaternary ammonium salt in the dispersant, the interfacial bonding between the organic phase (polyurethane) and the inorganic phase (cement, fine sand) was weakened, resulting in prolonged gelation time, reduced curing efficiency, and difficulty in quickly responding to the emergency sealing needs of large-flow seepage. This confirms the synergistic effect of EAA and the underwater self-healing dispersant—EAA, by filling and strengthening the structure, buffering expansion stress, and enhancing interfacial affinity, works with the dispersant to improve the overall performance of the slurry. Comparative Example 3, due to improper fine sand gradation (too much 40-80 mesh fine sand and too little 80-120 mesh fine sand), performed worse than the Example. Its water retention rate decreased. The excessively high proportion of coarse sand increased the voids between slurry particles, weakening the overall resistance to water erosion and resulting in insufficient compaction of the solidified body. This led to reduced bond strength with concrete, affecting interfacial bonding in dry, wet, and alkaline environments. The resulting gelled structure exhibited poor uniformity due to localized stress concentration caused by aggregate gradation imbalance, leading to decreased long-term durability. This demonstrates that a reasonable fine sand gradation (a proportional mix of 40-80 mesh and 80-120 mesh) is crucial for ensuring slurry density, strength, and impermeability, forming a synergistic performance system together with underwater self-healing non-dispersant and EAA components.In summary, Comparative Examples 1-3 demonstrate from different perspectives the crucial role of the core components (underwater self-healing non-dispersant agent, ethylene-acrylic acid copolymer) and raw material gradation in this invention. The absence of any core component or imbalance in gradation will lead to significant deterioration in the slurry's anti-dispersion properties, bonding strength, curing efficiency, and other properties. The examples effectively solve these problems through the synergistic effect of each component, demonstrating excellent high-flow-rate seepage and leakage plugging effects.

[0059] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. An underwater self-healing non-dispersible agent, characterized in that, The raw material composition and mass percentage are as follows: 5-10% of argan oil, 3-7% of nano hydroxyapatite, 2-5% of chitosan quaternary ammonium salt, 10-20% of calcium sulfoaluminate, 5-12% of magnesium oxide, 0.5-2% of graphene oxide, 7-15% of bentonite, and 40-65% of deionized water.

2. The underwater self-healing non-dispersible agent according to claim 1, characterized in that, The nano-hydroxyapatite has a particle size of 20-40 nm and a purity ≥99 wt%; the calcium sulfoaluminate is high-purity calcium sulfoaluminate with a purity ≥99 wt%; the magnesium oxide has a particle size of 30-50 nm and a purity ≥99.9 wt%; the graphene oxide has a sheet diameter of 15-30 μm and a thickness of 8-20 nm; and the bentonite is sodium-based bentonite with a particle size of 30-80 μm.

3. The underwater self-healing non-dispersant agent according to claim 1, characterized in that, The mass ratio of the prickly pear jelly to calcium sulfoaluminate is 1:1.8-2.2; the mass ratio of the nano-hydroxyapatite to graphene oxide is 3.5-5:

1.

4. The underwater self-healing non-dispersant agent according to claim 1, characterized in that, The mass ratio of magnesium oxide to bentonite is 1:1.2-1.5; the ratio of the total mass of the prickly ash gel and chitosan quaternary ammonium salt to the total mass of calcium sulfoaluminate and magnesium oxide is 1:2-2.

5.

5. A method for preparing the underwater self-healing non-dispersible agent according to any one of claims 1-4, characterized in that, The specific steps are as follows: The nano-hydroxyapatite and graphene oxide are added to deionized water and ultrasonically dispersed to obtain a nano-dispersion with active groups. Then, under heating conditions, argan oil, chitosan quaternary ammonium salt and bentonite are added and stirred at high speed until uniform. Then, the mixture is cooled to room temperature and calcium sulfoaluminate and magnesium oxide are added and stirred at low speed until uniform. Finally, the mixture is vacuum dried, pulverized and sieved to obtain a powdered finished product.

6. The method for preparing the underwater self-healing non-dispersant according to claim 5, characterized in that, The ultrasonic dispersion treatment time is 20-30 min; the heating temperature is 60-70℃; the high-speed stirring speed is 800-1000 rpm, and the stirring time is 30-40 min; the low-speed stirring speed is 300-500 rpm, and the stirring time is 10-20 min; the vacuum drying temperature is 40-50℃, and the drying time is 10-12 h; and the sieving is done through an 80-120 mesh sieve.

7. A high-flow-rate seepage-stopping composite grouting material prepared from the underwater self-healing non-dispersible agent according to any one of claims 1-4, characterized in that, The raw materials and their proportions are as follows: 100-120 parts hydrophilic polyurethane, 50-60 parts silicate cement, 5-8 parts internal curing material, 3-5 parts organophosphonic acid compound, 1-2 parts sodium silicate, 5-8 parts fumed silica, 10-15 parts 40-80 mesh fine sand, 10-15 parts 80-120 mesh fine sand, 2-3 parts underwater self-healing non-dispersant agent, and 2-4 parts ethylene acrylic acid copolymer.

8. The high-flow-rate seepage-stopping composite grouting material according to claim 7, characterized in that, The hydrophilic polyurethane has a viscosity ≤600 mPa·s and a gel time ≤60 s; the silicate cement is ordinary silicate cement with a strength grade of 42.5 or higher; the organophosphonic acid compound is aminotrimethylenephosphonic acid or hydroxyethylidene diphosphonic acid; the sodium silicate is powdered sodium silicate with a silica content of 52.0-56.0 wt% and a particle size ≤60 μm; the fumed silica is hydrophilic fumed silica with a specific surface area of ​​300-500 m² / s. 2 / g, with a particle size of 10-30nm; the acrylic acid content in the ethylene-acrylic acid copolymer is 8-10wt%; the mass ratio of the hydrophilic polyurethane to the total mass of silicate cement, 40-80 mesh fine sand and 80-120 mesh fine sand is 1.3-1.5:

1.

9. A method for preparing a high-flow-rate seepage-stopping composite grouting material as described in claim 7 or 8, characterized in that, The specific steps are as follows: 1) Weigh the raw materials according to the proportions and set aside; 2) Mix silicate cement, internal curing material, organophosphonic acid compound, sodium silicate, fumed silica, 40-80 mesh fine sand, 80-120 mesh fine sand and underwater self-healing non-dispersant agent evenly to obtain mixed component A; 3) Slowly add the mixed component A obtained in step 1) to the hydrophilic polyurethane and stir evenly with a high-speed mixer to obtain mixed component B; 4) Slowly heat the ethylene-acrylic acid copolymer until it becomes completely liquid, then add it to the mixed component B obtained in step 3). Stir evenly using a high-speed mixer to obtain a high-flow-rate seepage-stopping composite grout.

10. The application of the underwater self-healing non-dispersant agent according to any one of claims 1-4 and the high-flow-rate seepage-stopping composite grouting material according to claim 7 or 8 in the field of concrete.

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