Organic-inorganic hybrid modified grouting material and application thereof

Abstract

The invention provides an organic-inorganic hybrid modified grouting material and application thereof, the organic-inorganic hybrid modified grouting material comprises a component A and a component B, and the mass ratio of the component A to the component B is 1: 1; the component A comprises the following components in parts by mass: 100 parts of a polyisocyanate prepolymer, 6-12 parts of a silane coupling agent, 15-25 parts of an organic solvent and 0-5 parts of a surfactant; the silane coupling agent contains active hydrogen and an alkoxy silane group; and the component B comprises the following components in parts by mass: 100 parts of a water glass solution, 1.5-5 parts of a latent curing accelerator and 0-5 parts of water. Through molecular design, the water glass (component B) is endowed with the functions of'water triggering and rapid construction of an inorganic network skeleton ', and meanwhile, the modified isocyanate (component A) can be subjected to deep chemical coupling with an inorganic network to form an organic-inorganic interpenetrating network structure combined by strong chemical bonds; therefore, the instantaneous residence of the slurry under the flowing water condition and the final high-strength, high-toughness and water-resistant consolidation are realized.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering and geological disaster prevention technology, specifically to an organic-inorganic hybrid modified grouting material and its application. Background Technology

[0002] In the construction of deep mineral resource mining, water conservancy and hydropower projects, and transportation tunnels, vertical shafts often need to traverse complex geological structures, especially weak fault fracture zones. These strata are characterized by fractured rocks, extremely low strength, poor self-stability, and high water content, posing significant safety hazards to construction, such as water inrush, mudslides, large deformation of surrounding rock, and even collapses.

[0003] Currently, cement-based grouts or chemical grouts are commonly used for pre-grouting or post-grouting reinforcement. Cement-based grouts have disadvantages such as poor injectability, difficulty in controlling setting time, low bonding strength with weak rocks, high brittleness, and insufficient impermeability and durability. While pure organic chemical grouts (such as polyurethane and epoxy resin) have good permeability and high strength, they are expensive, have poor aging resistance, are not environmentally friendly, and are easily dispersed and diluted in high-pressure, water-rich environments.

[0004] In existing technologies, water glass and polyisocyanate prepolymers are often simply blended to improve the flame retardancy of polyurethane. However, this approach mainly involves physical mixing of the two components and does not address the need for rapid response and strong interfacial bonding in water-rich environments. Consequently, the resistance to erosion under dynamic water conditions is limited, and the solidified body exhibits a weakly bonded two-phase structure with insufficient long-term stability. Summary of the Invention

[0005] In view of the technical problems existing in the background art, this application provides an organic-inorganic hybrid modified grouting material and its application, aiming to solve the technical problems of high cost, poor permeability and environmental unfriendliness of existing grouting materials.

[0006] In a first aspect, embodiments of this application provide an organic-inorganic hybrid modified grouting material, comprising component A and component B, wherein the mass ratio of component A to component B is 1:1; Component A, by mass parts, includes 100 parts of polyisocyanate prepolymer, 6-12 parts of silane coupling agent, 15-25 parts of organic solvent, and 0-5 parts of surfactant; the silane coupling agent contains active hydrogen and alkoxysilane groups; Component B, by mass, includes 100 parts of water glass solution, 1.5 to 5 parts of latent curing accelerator, and 0 to 5 parts of water.

[0007] Secondly, this application provides an application of an organic-inorganic hybrid modified grout in the water plugging and reinforcement of high-pressure, water-rich, and fractured rock strata in deep vertical shafts and tunnels.

[0008] The advantages of this application, which differ from existing technical solutions, include: (1) A novel water-triggered hybridization mechanism: water glass in component B rapidly gels under the water-triggering effect of the water-rich bottom layer, forming an initial inorganic framework network, which enables rapid retention of the slurry; the silane-modified isocyanate in component A then chemically crosslinks with the inorganic network through covalent bonds (Si-O-Si), forming a hybrid structure that runs through the entire structure.

[0009] (2) Excellent resistance to erosion and early strength: Water glass can solidify within tens of seconds to minutes after contact with water (or triggered by an accelerator), providing immediate strength to resist water erosion. Subsequent chemical hybridization reactions rapidly enhance the overall strength.

[0010] (3) High strength, toughness and water resistance final solidified body: The interpenetrating network connected by Si-O-Si covalent bonds overcomes the fatal shortcomings of traditional water glass gels, such as high brittleness, low strength and poor water resistance. It also avoids the problems of high shrinkage and high cost of pure polyurethane, and obtains a solidified body with both high compressive strength (can exceed 30MPa) and good toughness.

[0011] (4) Controllable reaction and construction performance: By selecting the water glass modulus and adjusting the type and amount of latent accelerator, the gelation time of component B can be precisely controlled; by designing the grafting rate of silane in component A, the hybrid reaction rate can be adjusted. The combination of the two allows the grout to have an adjustable setting time to adapt to different water plugging conditions.

[0012] (5) Good environmental protection and economy: Water glass is used as the main raw material, which reduces the amount and cost of organic matter and is more environmentally friendly.

[0013] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Detailed Implementation

[0014] The embodiments of the technical solution of this application will be described in detail below. The following embodiments are only used to illustrate the technical solution of this application more clearly, and are therefore only examples, and should not be used to limit the scope of protection of this application.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion.

[0016] There is an urgent need for a new type of grouting material that can utilize the low cost, high permeability and environmentally friendly properties of water glass, introduce a high-strength organic network, and achieve rapid structuring and strong interfacial chemical hybridization upon contact with water.

[0017] To address the technical problems of high cost, poor permeability, and environmental unfriendliness of existing grouting materials, this application provides an organic-inorganic hybrid modified grouting material and its application. This invention offers an innovative modified isocyanate-water glass hybrid grouting material. Its core lies in molecular design, endowing water glass (component B) with the function of "water-triggered + rapid construction of an inorganic network framework," while simultaneously enabling the modified isocyanate (component A) to undergo deep chemical coupling with this inorganic network, forming an organic-inorganic interpenetrating network structure bound by strong chemical bonds. This achieves instantaneous retention of the grout under dynamic water conditions and final high-strength, high-toughness, and water-resistant consolidation.

[0018] In a first aspect, embodiments of this application provide an organic-inorganic hybrid modified grouting material, comprising component A and component B, wherein the mass ratio of component A to component B is 1:1; Component A, by mass parts, includes 100 parts of polyisocyanate prepolymer, 6-12 parts of silane coupling agent, 15-25 parts of organic solvent, and 0-5 parts of surfactant; the silane coupling agent contains active hydrogen and alkoxysilane groups; Component B, by mass, includes 100 parts of water glass solution, 1.5 to 5 parts of latent curing accelerator, and 0 to 5 parts of water.

[0019] In the technical solution of this application embodiment, the silane coupling agent in component A contains active hydrogen that can react with NCO and hydrolyzable alkoxysilane groups. The silane coupling agent reacts with some of the NCO groups of the polyisocyanate prepolymer to chemically bond the hydrolyzable alkoxysilane groups to the prepolymer chain, thereby obtaining a silane coupling agent-terminated modified polyisocyanate prepolymer.

[0020] The water glass in component B hydrolyzes in water to generate active silanol groups, which can undergo a condensation reaction with the polyisocyanate prepolymer modified by silane coupling agent to form Si-O-Si covalent bridges, thereby achieving chemical hybridization of organic and inorganic phases.

[0021] The interpenetrating network connected by Si-O-Si covalent bonds overcomes the fatal shortcomings of traditional water glass gels, such as high brittleness, low strength, and poor water resistance, and also avoids the problems of high shrinkage and high cost of pure polyurethane, thus obtaining a solidified body with both high compressive strength (exceeding 30MPa) and good toughness.

[0022] Furthermore, in some embodiments, the polyisocyanate prepolymer is prepared from a polyisocyanate and a polyol; Polyisocyanates include at least one of toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl polyisocyanate; Polyols include at least one of polyether polyols and polyester polyols.

[0023] Furthermore, in some embodiments, the preparation method of the polyisocyanate prepolymer includes the following steps: stirring and dehydrating the polyol in a closed reactor at 120°C for 1-2 hours until the moisture content is less than 0.05%; The dehydrated polyol was cooled to 60°C, and a measured amount of polyisocyanate was slowly added dropwise under dry nitrogen protection. After the addition was complete, the mixture was stirred and kept at 80°C for 2-4 hours to allow the reaction to proceed fully. The mass percentage of NCO in the product was determined. When the measured value reached the theoretical design value, the reaction was stopped, the temperature was lowered, and the product was discharged to obtain the polyisocyanate prepolymer.

[0024] Furthermore, in some embodiments, the NCO content of the polyisocyanate prepolymer is 15% to 25%.

[0025] Furthermore, in some embodiments, the silane coupling agent includes at least one of KH550 and KH-792.

[0026] Furthermore, in some embodiments, the organic solvent includes at least one of acetone and ethyl acetate.

[0027] Furthermore, in some embodiments, the surfactant includes ethylene oxide and propylene oxide in a mass ratio of 7:3 to 5:5.

[0028] Furthermore, in some embodiments, the water glass solution has a modulus of 2.0 to 3.3 and a solid content of 30% to 40%.

[0029] Furthermore, in some embodiments, the latent curing accelerator includes a microcapsule-encapsulated acidic substance, which includes at least one of sodium fluorosilicate, potassium fluorosilicate, phosphoric acid, acidic aluminum sol, and aluminum citrate.

[0030] In the technical solution of this application embodiment, the latent curing accelerator releases hydrogen ions or high-valence metal ions when it comes into contact with water or is heated. Its function is to slowly release ions that promote water glass gelation after the slurry is mixed and injected into the formation, triggered by groundwater or geothermal temperature, thereby controlling the generation rate of the water glass inorganic network and matching it with the reaction and diffusion process of component A.

[0031] Secondly, embodiments of this application provide an application of an organic-inorganic hybrid modified grout in water plugging and reinforcement of high-pressure, water-rich, and fractured rock strata in deep vertical shafts and tunnels.

[0032] Furthermore, in some embodiments, the following steps are included: S1. A dual-liquid grouting device is used to deliver component A and component B to the orifice mixing device respectively; S2. In the mixing device, components A and B are thoroughly mixed using a high-speed mixer with a rotation speed of 1000~2000 r / min to form the grout to be injected. S3. Inject the grout to be injected into the target water-rich formation. The water in the water-rich formation triggers the gelation of water glass in component B and initiates the hybridization reaction between components A and B to form a permanent solidified body.

[0033] In the technical solution of this application embodiment, a high-pressure grouting pump is used to inject the grout to be injected into the weak fault zone or fractured rock mass of the deep vertical shaft under high pressure. It can achieve strength in 0.5 hours, reach more than 10 MPa in 12 hours, reach more than 20 MPa in 1 day, and reach more than 30 MPa in 3 days, thus realizing the reinforcement and strengthening of the weak fault zone.

[0034] After injection, component B in the grout comes into contact with free water in the formation, triggering a preferential cross-linking reaction to form an initial structure resistant to erosion; subsequently, under the guidance of the interfacial chemical coupling agent, it develops into a permanent solidified body.

[0035] Furthermore, in some embodiments, the grouting pressure during grouting is 0.5 to 2.0 MPa higher than the hydrostatic pressure of the water-rich formation.

[0036] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0037] 1. Example 1: Standard Formula (Universal Dynamic Water Seal) (1) Slurry preparation Solution A: Take 100 parts of polyisocyanate prepolymer with NCO content of 18.5%, react with 8 parts of silane coupling agent KH-550 at 60℃ for 3 hours, add 15 parts of acetone to dilute, and obtain modified isocyanate solution.

[0038] Solution B: Take 100 parts of sodium silicate with a modulus of 2.8, add 3 parts of sodium fluorosilicate powder with microcapsules, and stir evenly to obtain a modified silicate solution.

[0039] (2) Application scenarios and effects This solution was used to treat fissure water inflow at a water pressure of 0.3 MPa and a moderate flow velocity in a 500m deep vertical shaft of a coal mine. After a 1:1 mixture of solutions A and B was injected, the solution rapidly solidified within 5 minutes, effectively resisting water flow and preventing dispersion. After 3 days of curing, the solidified body achieved a compressive strength of 35.5 MPa and exhibited good water resistance.

[0040] 2. Example 2: Rapid-setting formula (for high-pressure water inrush emergency) (1) Slurry preparation Solution A: The preparation method is the same as in Example 1, but the amount of KH-550 is increased to 12 parts, resulting in higher reactivity.

[0041] Solution B: Take 100 parts of sodium silicate with a modulus of 2.4 and add 5 parts of a composite coagulant consisting of microcapsule-encapsulated aluminum citrate and microcapsule-encapsulated phosphoric acid.

[0042] (2) Application scenarios and effects This solution was used to seal a 0.8 MPa high-pressure jetting water inrush in a 600m deep vertical shaft of a pumped storage power station. Liquids A and B were mixed in a 1:1 ratio and directly sprayed to the outlet. The slurry rapidly gelled within 1 minute, forming a stop plug, and the water inrush was essentially stopped within 30 minutes. The solidified body had a 3-day compressive strength of 31.0 MPa, meeting the sealing requirements.

[0043] 3. Example 3: High-permeability formulation (micro-crack reinforcement) (1) Slurry preparation Solution A: 100 parts of low-viscosity MDI-type polyisocyanate prepolymer were reacted with 6 parts of silane coupling agent KH-792 and diluted with 25 parts of ethyl acetate to obtain Solution A with extremely low viscosity (about 80 mPa·s).

[0044] Solution B: 100 parts of high modulus (3.0) potassium silicate, 1.5 parts of microcapsule-encapsulated potassium fluorosilicate, and 5 parts of water are added for dilution.

[0045] (2) Application scenarios and effects This method was used to reinforce a 600m deep, weak, and fractured rock mass rich in micro-fractures (<0.1mm) at a pumped storage power station. A and B grouts were injected at a 1:1 ratio under low pressure. The grout exhibited excellent permeability, effectively penetrating the micro-fracture network. After 3 days of curing, the loose rock mass was consolidated into a complete block with a compressive strength of 39.8 MPa, achieving overall reinforcement of the surrounding rock.

[0046] These three examples demonstrate that by adjusting the type and amount of silane coupling agent, the modulus of water glass and the setting accelerator, as well as the type of solvent, the initial setting time, flow properties, viscosity and final strength of this grout can be precisely controlled, thereby forming a series of products that can flexibly meet the different needs of deep vertical shaft weak fault zone treatment, such as emergency sealing of high-pressure water inrush and reinforcement of micro-fracture seepage.

[0047] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. An organic-inorganic hybrid modified grout, characterized in that, It includes component A and component B, wherein the mass ratio of component A to component B is 1:1; Component A, by mass parts, comprises 100 parts of polyisocyanate prepolymer, 6-12 parts of silane coupling agent, 15-25 parts of organic solvent, and 0-5 parts of surfactant; the silane coupling agent contains active hydrogen and alkoxysilyl groups. Component B, by mass, comprises 100 parts of water glass solution, 1.5 to 5 parts of latent curing accelerator, and 0 to 5 parts of water.

2. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The polyisocyanate prepolymer is prepared from polyisocyanates and polyols; The polyisocyanate includes at least one of toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl polyisocyanate; The polyol includes at least one of polyether polyol and polyester polyol.

3. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The NCO content of the polyisocyanate prepolymer is 15%~25%.

4. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The silane coupling agent includes at least one of KH550 and KH-792.

5. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The organic solvent includes at least one of acetone and ethyl acetate.

6. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The water glass solution has a modulus of 2.0 to 3.3 and a solid content of 30% to 40%.

7. The organic-inorganic hybrid modified grouting material according to claim 1, characterized in that, The latent curing accelerator comprises an acidic substance encapsulated in microcapsules, wherein the acidic substance comprises at least one of sodium fluorosilicate, potassium fluorosilicate, phosphoric acid, acidic aluminum sol, and aluminum citrate.

8. The application of an organic-inorganic hybrid modified grout as described in any one of claims 1 to 7 in water plugging and reinforcement of high-pressure, water-rich, and fractured rock strata in deep vertical shafts and tunnels.

9. The application of the organic-inorganic hybrid modified grouting material according to claim 8, characterized in that, Includes the following steps: S1. A dual-liquid grouting device is used to deliver component A and component B to the orifice mixing device respectively; S2. In the mixing device, components A and B are mixed evenly to form the grout to be injected. S3. The grout to be injected is injected into the target water-rich formation. The water in the water-rich formation triggers the gelation of water glass in component B and initiates the hybridization reaction between components A and B to form a permanent solidified body.

10. The application of the organic-inorganic hybrid modified grouting material according to claim 9, characterized in that, The grouting pressure during grouting is 0.5~2.0 MPa higher than the hydrostatic pressure of the water-rich strata.