Cement-water glass composite grouting material and preparation method thereof

Abstract

The invention relates to the field of geotechnical engineering grouting materials, and discloses a cement-water glass composite grouting material, which is characterized by comprising a liquid A, a liquid B and a liquid C. The liquid A comprises the following components in parts by weight: 525-700 parts of cement and 350-525 parts of water; the liquid B comprises the following components in parts by weight: 350 parts of water glass solution; the liquid C comprises the following components in parts by weight: 60-100 parts of a modifier solution; wherein the water cement ratio of the liquid A is 0.5-1.0, and the volume ratio of the liquid A to the liquid B is 1: 0.1-1: 1.5. The technical problems that in the prior art, traditional cement-based grout is difficult to meet the high-strength reinforcement requirement and poor in flowing water dispersion resistance, and consequently performance regulation and control are unbalanced are solved, accurate and controllable condensation and adjustable fluidity are achieved, the scene requirements of tunnel reinforcement, seepage prevention and leaking stoppage, mine supporting and the like are met, and the high-strength, fast-setting and durable characteristics are achieved.

Description

Technical Field

[0001] This application relates to the field of grouting materials for geotechnical engineering, and particularly to a cement-sodium silicate composite grouting material and its preparation method. Background Art

[0002] The grouting technology is widely used in stratum reinforcement, structural reinforcement, and anti-seepage and plugging projects. The core lies in whether the grout can effectively penetrate and consolidate the target geotechnical body. The grouting material needs to have high permeability, rapid setting, and long-term durability to cope with complex geological conditions and dynamic water environments. Traditional cement-based grouts are only applicable to coarse sand or wide fissure strata (permeability coefficient > 5×10-2 cm / s) due to their large particle size, and their 28-day compressive strength is relatively low (5-15 MPa), making it difficult to meet the requirements of high-strength reinforcement. Chemical grouts, although they can be injected into microfissures, are costly, 6-8 times that of cement grout, and have environmental protection hazards, restricting their engineering applicability.

[0003] In addition, traditional grouting materials perform poorly under dynamic water conditions. The stone formation rate of ordinary cement-sodium silicate grouts is less than 70% when the dynamic water pressure > 0.3 MPa, and the bond strength decreases significantly. Existing anti-washout agents can improve the retention rate of the grout, but they often delay setting or reduce the final strength, resulting in an imbalance in performance regulation. For example, when the retarder dosage is too high (> 2%), the 28-day strength will decrease by 15%-20%. Although the early-strength agent can improve the early strength, it inhibits the later strength growth and affects the long-term stability.

[0004] Therefore, there is an urgent need to develop a new type of grouting material that can ensure high permeability while having excellent dynamic water anti-washout performance, adjustable strength development, and environmental protection and economy. The present invention solves the contradictory problems of the prior art by optimizing the material ratio and structural design, providing a better solution for grouting projects under complex geological conditions. Summary of the Invention

[0005] This application provides a cement-sodium silicate composite grouting material and its preparation method, which solves the technical problems in the prior art that traditional cement-based grouts are difficult to meet the requirements of high-strength reinforcement, have poor dynamic water anti-washout performance, and result in an imbalance in performance regulation. It realizes precise controllability of setting and adjustable fluidity, meets the requirements of scenarios such as tunnel reinforcement, anti-seepage and plugging, and mine support, and has the characteristics of high strength, rapid setting, and durability.

[0006] The present application provides a cement-sodium silicate composite grouting material, which is characterized by comprising liquid A, liquid B and liquid C. The components of liquid A are: 525-700 parts by weight of cement and 350-525 parts by weight of water; the components of liquid B are: 350 parts by weight of sodium silicate solution; the components of liquid C are: 60-100 parts by weight of modifier solution; wherein, the water-cement ratio of liquid A is 0.5-1.0, and the volume ratio of liquid A to liquid B is 1:0.1-1:1.5.

[0007] Further, the cement is selected from portland cement, ordinary portland cement or sulfoaluminate cement, and the strength grade is 32.5, 42.5 or 52.5.

[0008] Further, the sodium silicate is sodium silicate or potassium silicate with a modulus of 2.0-3.0 and a Baume degree of 30-40.

[0009] Further, the modifier solution comprises at least one of the following components: stabilizer: polyvinyl alcohol; retarder: sodium tripolyphosphate; water reducer: naphthalene-based water reducer; additional admixture: selected from one or more of silica fume, fly ash, slag powder, nano-silica.

[0010] Further, the mixing mass ratio of the modifier to water is 0.5-1.5:1.

[0011] The present application also provides a preparation method of the cement-sodium silicate composite grouting material, comprising the following steps: S1, preparing liquid A: mixing 525-700 parts by weight of cement with 350-525 parts by weight of water, controlling the water-cement ratio to be 0.5-1.0, and stirring at 400-600 rpm for 3-5 minutes to obtain a uniform cement slurry; S2, preparing liquid B: measuring 350 parts by weight of sodium silicate solution with a modulus of 2.0-3.0 and a Baume degree of 30-40 for standby; S3, preparing liquid C: mixing 60-100 parts by weight of modifier with water according to a mass ratio of 0.5-1.5:1; S4, preliminary mixing: mixing liquid A and liquid B according to an initial volume ratio of 3:1; S5, performance testing and adjustment: testing the initial setting time and fluidity parameters, and adjusting the volume ratio of liquid A to liquid B to 1:0.1-1:1.5 according to the test results; S6, final mixing: adding liquid C: stirring at 500-600 rpm for 3-5 minutes to obtain the final grouting material.

[0012] Further, in step S4, the ratio is dynamically adjusted according to the engineering environment: adjusted to A liquid:B liquid = 1:0.8 in a water-rich environment; adjusted to A liquid:B liquid = 1:0.3 in a dry environment; the addition amount of the retarder is adjusted according to the required setting time.

[0013] Further, in step S3, the modifier includes: polyvinyl alcohol stabilizer: 2-4 parts by weight; sodium tripolyphosphate retarder: 1.5-3 parts by weight; naphthalene series water reducer: 4-6 parts by weight; the additional admixture is selected from one or more of silica fume, fly ash, slag powder, and nano-silica.

[0014] Further, the addition amounts of the additional admixtures are as follows: silica fume 30-40 parts by weight; fly ash 20-25 parts by weight; slag powder 30 parts by weight; nano-silica 10-20 parts by weight.

[0015] Further, the final product of the composite grouting material controls the following performance indicators: initial setting time 2-4 minutes; Marsh funnel viscosity ≤ 12 seconds; bleeding rate within 2 hours ≤ 2.5%; stone formation rate ≥ 80% under a dynamic water pressure of 0.5 MPa.

[0016] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0017] Through the synergistic effect of the scientific formula in this application, the comprehensive performance of the grouting material has been improved. Polyvinyl alcohol is used as a stabilizer, which interacts with the cement-sodium silicate system to form a three-dimensional network structure, significantly enhancing the anti-seepage performance of the material. To optimize the construction performance, a naphthalene series water reducer is specifically selected to improve the rheology of the slurry. At the same time, by adding sodium tripolyphosphate as a retarder, precise control of the setting time is achieved, which can flexibly meet the construction requirements of different engineering stages. In addition, while ensuring the performance, fly ash, slag powder and other industrial by-products are innovatively introduced to replace part of the cement, significantly reducing the material cost and reflecting the green and environmental protection construction concept. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flowchart of the preparation method of the cement-sodium silicate composite grouting material in the embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The cement-sodium silicate composite grouting material and its preparation method of the present invention achieve high permeability, rapid setting, long-term durability and good adaptability to the dynamic water environment by optimizing the component ratio and mixing process. The following describes the implementation manner of the present invention in detail with specific embodiments.

[0020] Raw material preparation:

[0021] (1) Component A

[0022] Cement: Portland cement (strength grade 42.5), ordinary Portland cement or sulphoaluminate cement can be selected, and the strength grade can be 32.5, 42.5 or 52.5.

[0023] Water: Clean tap water or a water source meeting the engineering water use standard.

[0024] Ratio: 525 - 700 parts by weight of cement + 350 - 525 parts by weight of water, and the water-cement ratio is controlled between 0.5 and 1.0.

[0025] (2) Component B

[0026] Water glass: Sodium water glass or potassium water glass is used, with a modulus of 2.0 - 3.0 and a Baume degree of 30 - 40.

[0027] Ratio: 350 parts by weight of water glass solution, directly used as Component B for standby.

[0028] (3) Component C

[0029] Modifier: Includes a stabilizer (polyvinyl alcohol), a retarder (sodium tripolyphosphate), a water reducer (naphthalene-based water reducer), and an additional admixture (one or more of silica fume, fly ash, slag powder, nano-silica).

[0030] Ratio: 60 - 100 parts by weight of modifier + water (modifier: water = 0.5 - 1.5:1).

[0031] Preparation steps: Refer to Figure 1 as shown.

[0032] S1: Preparation of Component A

[0033] 1. Weigh 525 - 700 parts by weight of cement and 350 - 525 parts by weight of water according to the ratio.

[0034] 2. Add the cement and water to a mixer, and control the water-cement ratio between 0.5 and 1.0.

[0035] 3. Stir at a speed of 400 - 600 rpm for 3 - 5 minutes until a uniform cement slurry is formed, and set aside for standby.

[0036] S2: Preparation of Component B

[0037] 1. Measure 350 parts by weight of water glass solution (modulus 2.0 - 3.0, Baume degree 30 - 40).

[0038] 2. Directly use it as Component B for standby without additional treatment.

[0039] S3: Preparation of Component C

[0040] 1. Weigh 60 - 100 parts by weight of modifier (such as 40 parts of silica fume, 20 parts of fly ash, 3 parts of polyvinyl alcohol, 2 parts of sodium tripolyphosphate, 5 parts of naphthalene-based water reducer) according to the ratio.

[0041] 2. Mix the modifier and water according to a mass ratio of 0.5 - 1.5:1, and stir well until uniform, ensuring no precipitation or stratification.

[0042] S4: Initial mixing of Liquid A and Liquid B

[0043] 1. Mix Liquid A and Liquid B in an initial volume ratio of A:B = 3:1 (e.g., 3L of Liquid A + 1L of Liquid B).

[0044] 2. Stir at 300 rpm for 3 minutes and test the initial setting time.

[0045] If the initial setting time is too short (less than 30 seconds): 0.5 - 1 part of retarder (sodium tripolyphosphate) can be added to extend the setting time.

[0046] If the initial setting time is too long (more than 4 minutes): Reduce the retarder or adjust the A / B liquid ratio (e.g., increase the proportion of Liquid B).

[0047] S5: Final mixing (adding Liquid C)

[0048] 1. Add the prepared Liquid C to the A + B mixture.

[0049] 2. Stir at a high speed of 500 - 600 rpm for 5 minutes to ensure uniform mixing of the three components.

[0050] 3. The performance of the final product should meet the following requirements: Initial setting time: 2 - 4 minutes; Marsh funnel viscosity: ≤12 seconds; 2 - hour bleeding rate: ≤2.5%; Stone formation rate under a dynamic water pressure of 0.5 MPa: ≥80%.

[0051] S6: Performance testing and adjustment

[0052] 1. Fluidity test: Use a Marsh funnel viscometer to control the viscosity ≤12 seconds to meet the pumping requirements.

[0053] If the viscosity is too high: Water reducer (naphthalene - based water reducer) can be added or the water - cement ratio can be adjusted.

[0054] 2. Impermeability test: Determine the 2 - hour bleeding rate (≤2.5%) and the stone formation rate (≥80%) under a dynamic water pressure of 0.5 MPa.

[0055] If the bleeding rate is too high: Polyvinyl alcohol stabilizer can be added or the A / B liquid ratio can be adjusted.

[0056] 3. Dynamic ratio adjustment:

[0057] In a water - rich environment: A:B = 1:0.8 to extend the penetration time.

[0058] In a dry environment: A:B = 1:0.3 to accelerate the setting speed.

[0059] Construction application:

[0060] 1. Tunnel support:

[0061] In the CRD method, through grouting with a conduit, the ratio of liquid A / liquid B is adjusted to adapt to the water seepage volume of the heading face.

[0062] Water-rich section: Liquid A:Liquid B = 1:0.8, extend the penetration time.

[0063] Dry section: Liquid A:Liquid B = 1:0.3, accelerate the setting speed.

[0064] 2. Foundation reinforcement:

[0065] Use a high-pressure grouting pump for transportation, control the Marsh funnel viscosity ≤ 12 seconds, and ensure fluidity.

[0066] 3. Dynamic water environment:

[0067] Add polyvinyl alcohol stabilizer to improve the anti-washout property and ensure that the stone formation rate ≥ 80%.

[0068] Example comparison:

[0069] Table 1 shows the ratio (by weight parts) of each raw material in the cement-sodium silicate composite grouting material of Examples 1 to 6.

[0070]

[0071]

[0072] Table 2 shows the test results of the setting time, initial viscosity, compressive strength, and flexural strength of the slurry materials prepared in Examples 1 to 6 in Table 1.

[0073]

[0074] A cement-sodium silicate composite grouting material and its preparation method provided by this application solve the problems of poor injectability, insufficient strength, and weak adaptability to dynamic water of traditional grouting materials through scientific ratio and process optimization. Compared with the prior art, the present invention has the following remarkable beneficial effects:

[0075] 1. Superior comprehensive performance

[0076] Precisely controllable setting time: Through precise regulation of the sodium tripolyphosphate retarder, the initial setting time can be controlled within 2 - 4 minutes to meet the requirements of different engineering scenarios (such as rapid support or permeation grouting).

[0077] Significantly improved mechanical properties: The 3d compressive strength can reach 5 MPa to meet the requirements of early support; the 28d compressive strength is increased to 16.8 - 18.5 MPa, far exceeding that of traditional cement slurry (5 - 15 MPa).

[0078] Enhanced impermeability: The polyvinyl alcohol stabilizer forms an interpenetrating network structure. The bleeding rate within 2 hours is ≤ 2.5%, and the stone formation rate is ≥ 80% under a dynamic water pressure of 0.5 MPa, effectively resisting groundwater scouring.

[0079] 2. Flexible and efficient construction

[0080] Adjustable fluidity: Naphthalene-based water reducing agent optimizes the fluidity of the slurry (water-cement ratio 0.6 - 1.5), Marsh funnel viscosity ≤ 12 seconds, meeting the pumping requirements for narrow spaces (such as the CRD method in tunnels).

[0081] Stable in dynamic water environment: Strong anti-dilution property, stable performance under dynamic water conditions with a flow rate greater than 0.5 m / s, and high density of the stone body.

[0082] Dynamic ratio adaptation: The volume ratio of A / B liquid can be adjusted in real time according to the results of geological radar detection (1:0.8 in water-rich sections, 1:0.3 in dry sections), achieving "multiple uses of one material".

[0083] 3. Economical and environmentally friendly

[0084] Cost reduction: Industrial solid wastes such as fly ash and slag powder replace 30% - 40% of cement, and the material cost is only 1 / 6 - 1 / 8 of that of chemical slurries.

[0085] Green and sustainable: No harmful substances are added, high solid waste utilization rate, reduced carbon emissions, meeting the requirements of environmental protection policies.

[0086] 4. Wide range of application scenarios

[0087] Strong adaptability to complex geology: Suitable for conditions such as soft strata, water-rich sand layers, and fractured surrounding rocks, meeting the requirements of tunnel reinforcement, foundation seepage prevention, and mine support.

[0088] Good long-term durability: Admixtures (silica fume, nano-silica) fill micro-pores, inhibit shrinkage and cracking, the strength continues to increase at 28 days, and the engineering life is extended.

[0089] 5. Process standardization

[0090] Simple preparation process: It can be completed through three-step mixing (preliminary mixing of A + B → performance testing → final mixing of liquid C), with strong operability and suitable for large-scale production.

[0091] Stable quality control: Key parameters (initial setting time, viscosity, bleeding rate) can be accurately achieved through ratio adjustment, with high batch consistency.

[0092] Obviously, those skilled in the art can make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application is also intended to include these modifications and variations.

[0093] The above are only the preferred specific embodiments of the embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application, according to the technical solution and its concept of the present application, makes equivalent substitutions or changes, and should be covered within the protection scope of the present application.

Claims

1. A cement-sodium silicate composite grouting material, characterized in that, It includes liquid A, liquid B and liquid C. The components of liquid A: 525 - 700 parts by weight of cement and 350 - 525 parts by weight of water; The components of liquid B: 350 parts by weight of sodium silicate solution; The components of liquid C: 60 - 100 parts by weight of modifier solution; Among them, the water - cement ratio of liquid A is 0.5 - 1.0, and the volume ratio of liquid A to liquid B is 1:0.1 - 1:1.

5.

2. The cement-sodium silicate composite grouting material according to claim 1, wherein The cement is selected from Portland cement, ordinary Portland cement or sulphoaluminate cement, and the strength grade is 32.5, 42.5 or 52.

5.

3. The one-component cement-sodium silicate composite grouting material according to claim 2, wherein The sodium silicate is sodium silicate or potassium silicate with a modulus of 2.0 - 3.0 and a Baume degree of 30 - 40.

4. A cement-sodium silicate composite grouting material according to claim 1, characterized in that, The modifier solution contains at least one of the following components: Stabilizer: polyvinyl alcohol; Retarder: sodium tripolyphosphate; Water - reducing agent: naphthalene - based water - reducing agent; External admixture: selected from one or more of silica fume, fly ash, slag powder, nano - silicon dioxide.

5. The cement-sodium silicate composite grouting material according to claim 4, characterized in that, The mixing mass ratio of the modifier to water is 0.5 - 1.5:

1.

6. A preparation method of the cement-sodium silicate composite grouting material according to any one of claims 1-5, characterized in that, It includes the following steps: S1, Prepare liquid A: Mix 525 - 700 parts by weight of cement with 350 - 525 parts by weight of water, control the water - cement ratio at 0.5 - 1.0, and stir at 400 - 600 rpm for 3 - 5 minutes to obtain a uniform cement slurry; S2, Prepare liquid B: Measure 350 parts by weight of sodium silicate solution with a modulus of 2.0 - 3.0 and a Baume degree of 30 - 40 for standby; S3, Prepare liquid C: Mix 60 - 100 parts by weight of the modifier with water according to the mass ratio of 0.5 - 1.5:1; S4, Initial mixing: Mix liquid A and liquid B according to the initial volume ratio of 3:1; S5, Performance test and adjustment: Test the initial setting time and fluidity parameters, and adjust the volume ratio of liquid A to liquid B to 1:0.1 - 1:1.5 according to the test results; S6, Final mixing: Add liquid C: Stir at 500 - 600 rpm for 3 - 5 minutes to obtain the final grouting material.

7. The preparation method of the cement-sodium silicate composite grouting material according to claim 6, characterized in that, In step S4, the ratio is dynamically adjusted according to the engineering environment: In a water - rich environment, adjust to liquid A:liquid B = 1:0.8; In a dry environment, adjust to liquid A:liquid B = 1:0.3; The addition amount of the retarder is adjusted according to the required setting time.

8. The preparation method of the cement-sodium silicate composite grouting material according to claim 6, characterized in that, The modifier in step S3 contains: Polyvinyl alcohol stabilizer: 2 - 4 parts by weight; Sodium tripolyphosphate retarder: 1.5 - 3 parts by weight; Naphthalene - based water - reducing agent: 4 - 6 parts by weight; The external admixture is selected from one or more of silica fume, fly ash, slag powder, nano - silicon dioxide.

9. The preparation method of the cement-sodium silicate composite grouting material according to claim 8, characterized in that, The addition amount of the external admixture is: Silica fume 30 - 40 parts by weight; Fly ash 20 - 25 parts by weight; Slag powder 30 parts by weight; Nano - silicon dioxide 10 - 20 parts by weight.

10. The preparation method of the cement-sodium silicate composite grouting material according to claim 6, characterized in that, The final product of the composite grouting material controls the following performance indicators: Initial setting time 2 - 4 minutes; Marsh funnel viscosity ≤ 12 seconds; 2 - hour bleeding rate ≤ 2.5%; Stone formation rate ≥ 80% under a dynamic water pressure of 0.5 MPa.

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