Sunken area foundation strengthening material based on industrial solid waste synergistic gelling and preparation method and application of subsidence area foundation strengthening material

Abstract

The invention relates to a subsidence area foundation strengthening material based on industrial solid waste synergistic gelling, which is characterized by comprising the following raw materials in parts by weight: 80-95 parts of gelling main materials, 5-15 parts of composite alkaline excitant and 0.1-2 parts of functional regulator. The reinforcing material further comprises water, and the water gel accounts for 30%-50% of the weight of the cement main material. According to the invention, industrial solid waste is used as a cementing main material, a geopolymerization reaction is excited by the composite alkaline activator to form a compact gel structure, and the material is endowed with later strength and durability superior to those of traditional cement. And the function regulator can accurately regulate and control the coagulation time and fluidity of the slurry, can be used for preparing high-fluidity slurry for pressure pouring of microcracks, can also be used for preparing a plastic mixture for filling holes, and is excellent in construction adaptability. The material is low in cost and high in solid waste utilization rate, can be widely applied to reinforcement of places such as coal mining subsidence areas, and realizes unification of environmental protection benefits and engineering benefits.

Description

Technical Field

[0001] This invention belongs to the field of solid waste cementitious materials technology, specifically relating to a subsidence area foundation reinforcement material based on industrial solid waste synergistic cementation, its preparation method, and its application. Background Technology

[0002] As a major industrial nation, my country generates a large amount of industrial solid waste annually, such as fly ash, steel slag, and coal gangue. The storage of these wastes not only occupies vast amounts of land but also poses environmental and safety risks. Simultaneously, mineral resource extraction, particularly coal mining, has created large-scale coal mining subsidence areas. These areas suffer from problems such as developed fissures, cavities, and loose soil, leading to surface instability, reduced bearing capacity, and severely hindering the effective reuse of land resources and ecological restoration.

[0003] Traditional foundation reinforcement materials mainly rely on ordinary silicate cement. However, cement production is energy-intensive, generates significant carbon emissions, and is relatively expensive. Especially for applications like subsidence areas requiring large-scale, low-cost filling and reinforcement, cement-based materials are neither economically nor environmentally sound. In recent years, utilizing industrial solid waste to prepare geopolymers or alkali-activated cementitious materials has emerged as a promising alternative. These materials typically utilize high-silica, high-alumina solid waste (such as fly ash) and high-calcium solid waste (such as steel slag) reacted under alkaline conditions to generate cementitious products, which then solidify and develop strength.

[0004] However, existing solid waste-based cementitious materials still face challenges in practical applications. For example, the poor compatibility of solid wastes from different sources and with different compositions leads to large fluctuations in material properties; the workability of the slurry (flowability, setting time, etc.) is difficult to control precisely, affecting construction quality; and relying solely on a single activator may result in slow early strength development or insufficient later strength. Therefore, developing a synergistic cementitious material with controllable performance, good workability, low cost, and the ability to absorb a variety of industrial solid wastes on a large scale is of great significance for achieving efficient and green reinforcement of subsidence area foundations. Summary of the Invention

[0005] This invention provides a foundation reinforcement material for subsidence areas based on industrial solid waste co-aggregation, which can effectively solve the technical problems of high cost and large carbon emissions of traditional cement-based reinforcement materials, as well as the unstable performance and difficulty in workability control of existing solid waste-based cementitious materials, making it difficult to meet the requirements of large-scale foundation reinforcement in subsidence areas.

[0006] The first inventive point of this invention is: a foundation reinforcement material for subsidence areas based on industrial solid waste synergistic cementation, characterized in that the reinforcement material is composed of the following raw materials in parts by weight: 80-95 parts cementitious main material, 5-15 parts composite alkaline activator, and 0.1-2 parts functional regulator.

[0007] Furthermore, the reinforcing material also includes water, and the water-based adhesive accounts for 30%-50% of the weight of the coagulant.

[0008] Furthermore, the main gelling material includes high-silicon aluminum solid waste and high-calcium solid waste; the mass ratio of the high-silicon aluminum solid waste to the high-calcium solid waste is (1-3):1.

[0009] Furthermore, the high-silicon aluminum solid waste is selected from one or more of fly ash, coal gangue powder, and metakaolin; and / or, the high-calcium solid waste is selected from one or more of steel slag powder and carbide slag.

[0010] Furthermore, the main cementitious material also includes auxiliary silica materials, wherein the water-based adhesive of the auxiliary silica materials accounts for 0-15% of the weight of the main cementitious material; the auxiliary silica materials are selected from one or more of microsilica powder and ground quartz sand.

[0011] Furthermore, the composite alkaline activator comprises a solid alkali and a water glass solution; the solid alkali is selected from one or more of sodium hydroxide, potassium hydroxide, and anhydrous sodium sulfate; the modulus of the water glass solution is 1.0-2.0.

[0012] Furthermore, in the composite alkaline activator, the solid alkali has a mass ratio of (0.4-4):1 with the water glass solution based on solid content.

[0013] Furthermore, the functional regulator includes retarder and accelerator; The retarder is selected from one or more of boric acid, white sugar, and lignin sulfonate; The coagulant is selected from one or more of lithium carbonate, calcium nitrate, and sodium fluorosilicate.

[0014] The second inventive point of this invention is: a method for preparing foundation reinforcement materials for subsidence areas as described above, comprising the following steps: Step S1: Dry mix the solid components in the gelling main material to obtain a uniform dry mix; Step S2: Mix the composite alkaline activator with water to form an activator solution; Step S3: Mix and stir the activator solution, functional regulator and dry mix to form a homogeneous slurry.

[0015] Preferably, in step S3, the stirring time is 3-5 minutes and the stirring speed is 300-500 rpm.

[0016] The third inventive point of this invention is: the application of the above-mentioned subsidence area foundation strengthening material in the reinforcement of subsidence area foundation, wherein the subsidence area foundation strengthening material is prepared into a highly fluid slurry and injected into the cracks or pores of the subsidence area foundation by pressure injection. And / or, the foundation reinforcement material of the subsidence area is prepared into a plastic or viscous mixture and filled into the voids or collapsed areas of the foundation of the subsidence area by grouting. Preferably, the pressure of the pressure infusion is 0.5-1.0 MPa; Preferably, the foundation of the subsidence area is a coal mining subsidence area or a mining wasteland. Beneficial effects

[0017] The foundation reinforcement material for subsidence areas provided by this invention achieves significant environmental and economic benefits by synergistically utilizing industrial solid waste as the main cementitious material and employing composite alkaline activators and functional regulators. This solution not only disposes of solid wastes such as fly ash and steel slag on a large scale and at low cost, but also induces a geological polymerization reaction, enabling the material to form a dense gel structure. This results in superior later-stage strength, stiffness, and durability compared to traditional cement materials, providing a high-performance solution for subsidence area remediation.

[0018] At the engineering application level, this invention demonstrates excellent construction adaptability. By utilizing functional regulators, the setting time and fluidity of the grout can be precisely controlled. It can be used to prepare highly fluid grouts for pressure injection to penetrate micro-cracks, or to prepare plastic mixtures for filling voids, effectively ensuring reinforcement quality under different working conditions. Furthermore, its raw material combination is highly versatile and its technology is widely applicable, making it suitable for various geotechnical engineering reinforcement scenarios such as coal mining subsidence areas and abandoned mining sites, achieving an effective combination of solid waste resource utilization and foundation engineering reinforcement. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, a more detailed description is provided below. However, it should be understood that the description herein is merely for explaining this application and is not intended to limit its scope.

[0020] 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 belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. All reagents and instruments used herein are commercially available, and the characterization methods involved can be found in relevant descriptions in the prior art, and will not be repeated here.

[0021] To further understand this application, the following detailed description is provided in conjunction with the preferred embodiments. Example 1

[0022] This embodiment provides a subsidence area foundation reinforcement material based on industrial solid waste synergistic cementation. The reinforcement material is characterized by being composed of the following raw materials in parts by weight: 80-95 parts cementitious main material, 5-15 parts composite alkaline activator, and 0.1-2 parts functional regulator.

[0023] Using 80-95 parts of the cementitious main material as the material basis for the final strength, 5-15 parts of the composite alkaline activator are introduced to provide the necessary alkaline environment to destroy the glassy structure of solid waste particles and stimulate their potential activity, thereby promoting the formation of aluminosilicate network. At the same time, 0.1-2 parts of functional regulator are used to precisely control the timing of this complex cementation process, thereby ensuring the construction feasibility and the stability of the final performance of the material throughout the entire process from mixing to hardening.

[0024] Furthermore, the reinforcing material also includes water, and the water-based adhesive accounts for 30%-50% of the weight of the coagulant.

[0025] Water is not only the medium for mixing dry aggregates into a workable slurry, but it also directly participates in the geological polymerization reaction process as a carrier for the dissolution and migration of alkaline activators. Controlling the water content within the range of 30%-50% of the weight of the cementitious main material is to ensure sufficient fluidity of the slurry while avoiding the final structure becoming loose and losing strength due to excessive water, or the reaction becoming insufficient and construction difficult due to insufficient water.

[0026] Furthermore, the main gelling material includes high-silicon aluminum solid waste and high-calcium solid waste; the mass ratio of the high-silicon aluminum solid waste to the high-calcium solid waste is (1-3):1.

[0027] High-silicon aluminum solid waste primarily provides the network formations that constitute the geopolymer framework, while high-calcium solid waste, similar to cement hydration, provides calcium ions and calcium hydroxide, which can both accelerate the reaction and generate additional cementitious products. Maintaining a mass ratio of (1-3):1 between the two is to balance the reaction rate and the chemical stability of the final product, thereby obtaining a material system with excellent reactivity and mechanical properties.

[0028] Furthermore, the high-silicon aluminum solid waste is selected from one or more of fly ash, coal gangue powder, and metakaolin; and / or, the high-calcium solid waste is selected from one or more of steel slag powder and carbide slag.

[0029] Fly ash, coal gangue powder, and metakaolin, being high-silicon and high-alumina solid wastes, are ideal raw materials for constructing three-dimensional network structures of geopolymers due to their rich content of active silicon and aluminum. Meanwhile, high-calcium solid wastes such as steel slag powder and carbide slag, with their free calcium oxide or calcium silicate components, can regulate the pH of the system and provide a calcium source, thus jointly promoting the formation and development of the cementitious phase.

[0030] Furthermore, the main cementitious material also includes auxiliary silica materials, wherein the water-based adhesive of the auxiliary silica materials accounts for 0-15% of the weight of the main cementitious material; the auxiliary silica materials are selected from one or more of microsilica powder and ground quartz sand.

[0031] The addition of microsilica and ground silica sand is mainly used to adjust the silicon-aluminum ratio and silicon-calcium ratio in the reaction system. Microsilica, due to its extremely high activity and fineness, can quickly participate in the reaction and fill the pores, while ground silica sand can serve as micro-aggregate and long-term silicon source. Its 0-15% dosage allows for optimization of the microstructure and durability of the final product based on the fluctuation of the main material composition.

[0032] Furthermore, the composite alkaline activator comprises a solid alkali and a water glass solution; the solid alkali is selected from one or more of sodium hydroxide, potassium hydroxide, and anhydrous sodium sulfate; the modulus of the water glass solution is 1.0-2.0.

[0033] The primary function of solid alkalis such as sodium hydroxide is to rapidly increase the pH value of the system, creating initial conditions for the dissolution of solid waste particles. Water glass solutions with a modulus of 1.0-2.0 not only provide alkalinity, but more importantly, their silicate aggregates can directly participate in network construction as precursors. The combination of these two methods promotes the entire process from initiation to formation.

[0034] Furthermore, in the composite alkaline activator, the solid alkali has a mass ratio of (0.4-4):1 with the water glass solution based on solid content.

[0035] The activation efficiency was optimized by limiting the mass ratio of solid alkali to water glass solution to (0.4-4):1. This ratio ensures that the system has a sufficiently high initial alkalinity to rapidly initiate the reaction, while avoiding unstable gel structures or blooming due to excessive alkali, thus achieving an optimal balance between reaction rate and long-term performance.

[0036] Furthermore, the functional regulator includes retarder and accelerator; The retarder is selected from one or more of boric acid, white sugar, and lignin sulfonate; The coagulant is selected from one or more of lithium carbonate, calcium nitrate, and sodium fluorosilicate.

[0037] Retarder agents such as boric acid or sugar temporarily inhibit the excessively rapid increase in reaction rate through adsorption or complexation, allowing sufficient time for slurry delivery and injection. Conversely, accelerators such as lithium carbonate can significantly accelerate the nucleation and growth process of gel products, ensuring that the slurry can quickly build strength to support the foundation when needed. The combination of the two allows the material to flexibly cope with a variety of engineering scenarios. Example 2

[0038] This embodiment provides a method for preparing a foundation reinforcement material for subsidence areas based on Embodiment 1, including the following steps: Step S1: Dry mix the solid components in the gelling main material to obtain a uniform dry mix; Step S2: Mix the composite alkaline activator with water to form an activator solution; Step S3: Mix and stir the activator solution, functional regulator and dry mix to form a homogeneous slurry.

[0039] Preferably, in step S3, the stirring time is 3-5 minutes and the stirring speed is 300-500 rpm.

[0040] First, step S1 involves dry mixing to ensure a uniform distribution of all solid components, creating a consistent material basis for subsequent reactions. Next, in step S2, the activator is pre-dissolved in water to form a homogeneous solution, ensuring sufficient and rapid contact with the solid waste particles. Finally, in step S3, the solution, regulator, and dry mix are combined and stirred at 300-500 rpm for 3-5 minutes. This process aims to achieve a high degree of physical and chemical homogeneity in the slurry, laying the foundation for successful subsequent infusion and strength development. Example 3

[0041] This embodiment provides an application of the aforementioned subsidence area foundation strengthening material in the reinforcement of subsidence area foundations. The subsidence area foundation strengthening material is prepared into a highly fluid slurry and injected into the cracks or pores of the subsidence area foundation by pressure grouting. And / or, the subsidence area foundation reinforcement material is prepared into a plastic or viscous mixture and filled into the cavities or collapsed areas of the subsidence area foundation by grouting; preferably, the pressure of the pressure grouting is 0.5-1.0 MPa; preferably, the subsidence area foundation is a coal mining subsidence area or a mining wasteland.

[0042] For different defect morphologies in subsidence area foundations, the material is prepared into a highly fluid grout and injected under a pressure of 0.5-1.0 MPa, allowing it to effectively penetrate and seal fine cracks. For larger cavities or collapsed areas, it is prepared into a plastic or viscous mixture for filling, which avoids excessive material loss and provides effective support. This application method, tailored to the specific geological conditions of coal mining subsidence areas or abandoned mining sites, ensures that the material's performance is optimized. Example 4

[0043] Experimental Example 1

[0044] Raw material preparation Dry-mixed components of cementitious main material: fly ash: 60kg, steel slag powder: 30kg; Composite alkaline activator components: water glass solution (modulus 1.5): 6kg, sodium hydroxide solid: 2kg; Functional regulator: boric acid: 1kg, water: 36kg.

[0045] Its preparation method is as follows: Step S1: Dry Mixing Add 60 kg of fly ash and 30 kg of steel slag powder to a forced mortar mixer. Turn on the mixer and dry mix at 300 rpm for 3 minutes, until the mixed powder is observed to be of uniform color, with no visible color difference or lumps, thus obtaining a uniform dry mix. Temporarily discharge this dry mix and place it in a spare container.

[0046] Step S2: Prepare the activator solution First, add 36 kg of water to a plastic container. Then, slowly add 2 kg of solid sodium hydroxide, stirring gently with a glass rod until completely dissolved. This process is exothermic, so caution is advised. After the solution cools to room temperature, add 6 kg of water glass solution (modulus 1.5) and stir thoroughly with a glass rod for about 1 minute to form a homogeneous and clear composite activator solution.

[0047] Step S3: Mix and stir to form a slurry Clean and dry the mixer. Return all the dry mixture prepared in step S1 to the mixing pot. Start the mixer and, under low speed (300 rpm), uniformly pour all the activator solution prepared in step S2 into the dry mixture within 1 minute. Then, add 1 kg of boric acid powder to the pot. Increase the mixer speed to 450 rpm and continue stirring for 4 minutes. Observe the slurry until it becomes homogeneous, smooth, free of bleeding, and without visible lumps; this indicates the desired high-flowability foundation strengthening slurry has been obtained. Experimental Example 2

[0048] Raw materials: Cementitious main material: 45 kg of coal gangue powder and 10 kg of silica fume were used to replace the fly ash in Example 1; 30 kg of carbide slag was used to replace the steel slag powder. Composite alkaline activator: 8 kg of water glass with a modulus of 1.8 and 4 kg of anhydrous sodium sulfate solid were used to replace the original activator combination. Functional regulator: 1.5 kg of lithium carbonate was used to replace boric acid.

[0049] Preparation process: In step S1, coal gangue powder, carbide slag and microsilica powder need to be dry mixed together.

[0050] In step S2, the preparation order of the activator solution is as follows: first, dissolve the anhydrous sodium sulfate solid in water, then add the water glass solution. The stirring parameters in step S3 are the same as in Experimental Example 1. Everything else is the same as in Experimental Example 1. Experimental Example 3

[0051] Raw material differences: Main cementitious material: 45 kg fly ash and 15 kg metakaolin are used as high-silicon, high-alumina solid waste; 35 kg steel slag powder is used as high-calcium solid waste. Composite alkaline activator: 5 kg water glass with a modulus of 2.0 and 5 kg solid sodium hydroxide. Functional regulator: A mixture of 0.3 kg white sugar and 0.2 kg calcium nitrate.

[0052] Differences in preparation process: In step S1, fly ash, metakaolin and steel slag powder are dry mixed together.

[0053] Step S2 is the same as in Experimental Example 1. In Step S3, the white sugar and calcium nitrate are added together after the activator solution, and the stirring parameters are the same. Everything else is the same as in Experimental Example 1. Comparative Example 1

[0054] Differences in raw materials: Only 100 kg of ordinary Portland cement and 50 kg of water are used.

[0055] Differences in preparation process: Steps S1 and S2 are omitted.

[0056] Proceed directly to step S3: Add cement to the mixer, add all water while mixing, and mix using a standard cement paste mixing program (e.g., slow speed for 120 seconds, fast speed for 120 seconds) to obtain cement paste. Comparative Example 2

[0057] Raw material differences: The main cementitious material is 80 kg of fly ash and 10 kg of steel slag powder.

[0058] Composite alkaline activator: 3 kg of water glass with a modulus of 1.5 and 12 kg of solid sodium hydroxide were used. The water-to-binder ratio was the same as in Experimental Example 1.

[0059] Differences in preparation process: The procedures for steps S1, S2, and S3 are exactly the same as in Experimental Example 1. However, during the stirring process and after settling in step S3, obvious water bleeding and segregation of the slurry were observed, resulting in poor cohesiveness. Example 5

[0060] Performance testing: 1. Flowability test Test standard: GB / T 2419-2005 "Determination of Flowability of Cement Mortar" Test Summary: The test is conducted using a standard slurry table. The prepared fresh slurry is filled into a truncated cone mold, leveled, and then lifted vertically. The slurry table is started and, after 25 jumps, the expansion diameter of the bottom of the slurry in two vertical directions is measured and the average value is calculated. This value directly characterizes the flow properties of the slurry; the larger the value, the better the flow properties.

[0061] 2. Setting time test Test standard: GB / T 1346-2011 "Test Methods for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" Test Summary: The Vicat apparatus is used to test the penetration resistance of the grout. The depth of the probe sinking into the grout is measured periodically, and the time when the probe is at a specified distance from the bottom plate is recorded as the initial setting time. This parameter indicates that the grout begins to lose plasticity and is crucial for determining the workable time for construction.

[0062] 3. Compressive strength test Test standard: GB / T 17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)" Test Summary: The slurry is made into standard prism specimens and cured under standard conditions (20±1℃ in water) to the specified age. Then, a pressure testing machine is used to uniformly load the specimen at a rate of (2400±200) N / s until the specimen fails. The compressive strength values ​​at 3 days and 28 days are obtained by calculating the ultimate load per unit area. This is the core indicator for evaluating the final mechanical properties of the material.

[0063] 4. Qualitative evaluation of job performance Testing standards: No standard method; based on industry-standard engineering experience. Evaluation Summary: The condition of fresh slurry is mainly judged by visual observation and touch. High-quality slurry should be uniform and smooth, with good cohesion and no bleeding or segregation, while poor slurry will show obvious bleeding, aggregate separation or excessive dryness, which are not conducive to construction.

[0064] 5. Cost and Environmental Benefit Analysis Cost analysis basis: Estimated based on publicly available market prices. Environmental benefits are based on relevant national policies on the resource utilization of solid waste. Analysis Summary: Cost-effectiveness was qualitatively compared by estimating the cost of the main cementitious raw materials required per unit of production; environmental benefits were directly evaluated based on the total proportion of industrial solid waste in the formula. A higher solid waste content indicates better resource utilization and more prominent environmental benefits. The test results are shown in Table 1.

[0065] Table 1 Performance Test Results

[0066] Compressive strength analysis 28-day compressive strength: This is a key indicator for evaluating the final mechanical properties of a material.

[0067] Test Examples 1-3 (35.2-48.5 MPa) were all significantly higher than the 32.0 MPa of Comparative Example 1 (cement-based). This demonstrates that the final structural density and gel strength of the solid waste-based polymer system of the present invention fully meet and surpass those of traditional cement materials. Test Example 3, with its 48.5 MPa, is particularly outstanding, representing a strength increase of over 50%, indicating that its formulation (e.g., using metakaolin and optimized activators) can generate a superior gel phase.

[0068] Comparative Example 2 (18.6 MPa) exhibited extremely low strength, directly demonstrating the importance of the solid waste ratio limitation in claim 3. The severely imbalanced ratio of high-silicon aluminum to high-calcium solid waste (8:1) prevented the formation of an effective synergistic reaction, resulting in a loose structure.

[0069] 3-day compressive strength Test Examples 2 and 3 (12.1 and 15.5 MPa) were higher than Comparative Example 1 (10.5 MPa), indicating that by adding a coagulant or optimizing the activation process, the present invention can achieve rapid strength development and meet the requirements for rapid support.

[0070] Test Example 1 (8.5 MPa) had lower early strength due to the addition of a retarder, but this allowed time for its high-flowability injection process.

[0071] Comparative Example 2 (5.2 MPa) also showed extremely low early strength, indicating that an unreasonable ratio not only affected the later strength but also severely delayed the early reaction.

[0072] Condensation time analysis Test Example 1 (120 minutes) and Test Example 3 (95 minutes) had moderate initial setting times, longer than Example 2 but much shorter than Comparative Example 1 (180 minutes). This provided an ample working window for pressure grouting while avoiding the problem of excessively long waiting times for cement-based materials.

[0073] Experiment 2 (45 minutes) achieved rapid setting with a coagulant, which is very suitable for filling grouting, can quickly stabilize the collapsed area and prevent grout loss.

[0074] Comparative Example 2 (35 minutes) solidified too quickly, which is out of control and could lead to pipe blockage in actual engineering, preventing effective grouting. This, in turn, confirms the necessity of the functional regulator in claim 8.

[0075] Flowability / Workability Analysis: The slurries in Test Examples 1 and 3 (superior) are uniform and highly fluid, which ensures that they can penetrate into micro-cracks under pressure, achieving "micro-reinforcement".

[0076] Test Example 2 (Good) is in a plastic state. Although the flowability value is not high, it has good cohesion and is suitable for filling voids without excessive flow.

[0077] Comparative Example 2 (Poor) shows bleeding and segregation, which means that solid particles are separated from the slurry. This can lead to pipe blockage during grouting and form weak links in the hardened body. This is a deterioration state that must be avoided.

[0078] Cost and environmental benefits analysis: Cost of main cementitious raw materials: The costs of Experimental Examples 1-3 and Comparative Example 2 are "extremely low" because they mainly use industrial solid waste, while the cost of Comparative Example 1, which uses traditional cement-based materials, is "high". This gives the present invention a significant economic advantage in the treatment of large-scale subsidence areas.

[0079] Environmental benefits: The "excellent" rating of Experimental Examples 1-3 and Comparative Example 2 stems from their efficient utilization of solid waste. However, Comparative Example 2 demonstrates that environmental benefits alone, without performance support, are unapplicable. This invention successfully unifies "environmental benefits" with "engineering performance," achieving the ultimate goal of turning waste into treasure.

[0080] The performance test table systematically demonstrates the comprehensive superiority of the present invention: in terms of core mechanical properties (compressive strength), the optimized embodiment comprehensively surpasses traditional cement-based materials; by adjusting the functional regulators and proportions, the setting time and workability of the material can be precisely controlled, thereby flexibly adapting to different construction process requirements such as pressure grouting and filling; while achieving high performance, it greatly reduces raw material costs and solves the problem of solid waste disposal, achieving a win-win situation for environmental and economic benefits; moreover, the data of Comparative Example 2 strongly reflects that the limitation of the proportion range of each component in the claims is scientific and necessary, and is the core key to ensuring the final success of the material.

[0081] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A foundation reinforcement material for subsidence areas based on synergistic cementation of industrial solid waste, characterized in that, The reinforcing material is composed of the following raw materials in parts by weight: 80-95 parts of gelling agent, 5-15 parts of composite alkaline activator, and 0.1-2 parts of functional regulator.

2. The foundation reinforcement material for subsidence areas according to claim 1, characterized in that, The reinforcing material also includes water, and the water-based adhesive accounts for 30%-50% of the weight of the coagulant.

3. The foundation reinforcement material for subsidence areas according to claim 1, characterized in that, The main gelling material includes high-silicon aluminum solid waste and high-calcium solid waste; the mass ratio of the high-silicon aluminum solid waste to the high-calcium solid waste is (1-3):

1.

4. The foundation reinforcement material for subsidence areas according to claim 3, characterized in that, The high-silicon aluminum solid waste is selected from one or more of fly ash, coal gangue powder, and metakaolin; and / or, the high-calcium solid waste is selected from one or more of steel slag powder and carbide slag.

5. The foundation reinforcement material for subsidence areas according to claim 1, characterized in that, The main cementitious material also includes auxiliary silica materials, wherein the water-based adhesive of the auxiliary silica materials accounts for 0-15% of the weight of the main cementitious material; the auxiliary silica materials are selected from one or more of microsilica powder and ground quartz sand.

6. The foundation reinforcement material for subsidence areas according to claim 1, characterized in that, The composite alkaline activator comprises a solid alkali and a water glass solution; the solid alkali is selected from one or more of sodium hydroxide, potassium hydroxide, and anhydrous sodium sulfate; the modulus of the water glass solution is 1.0-2.

0.

7. The subsidence area foundation strengthening material according to claim 6, characterized in that, In the composite alkaline activator, the solid alkali has a mass ratio of (0.4-4):1 with the water glass solution based on solid content.

8. The foundation reinforcement material for subsidence areas according to claim 1, characterized in that, The functional regulators include retarder and accelerator; The retarder is selected from one or more of boric acid, white sugar, and lignin sulfonate; The coagulant is selected from one or more of lithium carbonate, calcium nitrate, and sodium fluorosilicate.

9. A method for preparing a foundation strengthening material for subsidence areas as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1: Dry mix the solid components in the gelling main material to obtain a uniform dry mix; Step S2: Mix the composite alkaline activator with water to form an activator solution; Step S3: Mix and stir the activator solution, functional regulator and dry mix to form a homogeneous slurry. Preferably, in step S3, the stirring time is 3-5 minutes and the stirring speed is 300-500 rpm.

10. The application of a subsidence area foundation strengthening material as described in any one of claims 1-8 in the reinforcement of subsidence area foundations, characterized in that, The foundation strengthening material in the subsidence area is prepared into a highly fluid slurry and injected into the cracks or pores of the foundation in the subsidence area by pressure injection. And / or, the foundation reinforcement material of the subsidence area is prepared into a plastic or viscous mixture and filled into the voids or collapsed areas of the foundation of the subsidence area by grouting. Preferably, the pressure of the pressure infusion is 0.5-1.0 MPa; Preferably, the foundation of the subsidence area is a coal mining subsidence area or a mining wasteland.

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