Foamed mud with volume expansion and shrinkage characteristic and preparation method thereof

Abstract

The invention relates to the technical field of building materials, in particular to foamed mud with volume expansion and shrinkage characteristics and a preparation method. The foam mud comprises the following components in parts by weight: 1000 parts of dry muck; 200 to 300 parts of a curing agent; 650 to 750 parts of water; 1-3 parts of a foaming agent; 1-2 parts of an anti-dispersing agent; and 2-4 parts of a stabilizer. The foam mud with the volume expansion and shrinkage characteristic is stable in volume after being cured, can be subjected to volume compression transportation, filling and other operations in an uncured stage due to the existence of internal closed-cell tough bubbles, and is suitable for engineering scenes such as foundation reinforcement, tunnel support, anti-seismic structures, cavity filling and underground plugging.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to a foam slurry with volume expansion and contraction characteristics and a preparation method thereof. Background Art

[0002] In traditional engineering construction, commonly used materials such as cement slurry, polymer grouting and foam concrete are mainly used for filling, reinforcement and sealing. However, existing materials have the following limitations: (1) Cement slurry: After solidification, cement slurry forms a rigid structure that cannot provide flexible rebound properties, and its volume changes irreversibly, making it difficult to adapt to dynamic load environments.

[0003] In application scenarios, cement slurry is mainly used for permanent filling and support, and lacks the buffering effect against transient loads or impacts.

[0004] (2) Chemical grouting materials (such as polyurethane grouting): Chemical grouting materials cure quickly, can fill voids and provide a certain degree of strength, but the cured structure is brittle and lacks durability and impact resistance.

[0005] These materials typically expand or solidify irreversibly, and once formed, they cannot achieve prestressing control or rebound functions. Their main applications are in compressed volume transportation, filling, and other scenarios.

[0006] (3) Foam concrete: Foam concrete reduces the material density by introducing bubbles, providing a certain degree of thermal insulation and filling effects, but its mechanical properties are limited. After solidification, the bubbles cannot be controlled and cannot form an outward rebound force.

[0007] Under high load conditions, foam concrete is prone to permanent deformation or cracking, making it difficult to achieve dynamic prestressing effects.

[0008] The existing materials have the following problems: (1) Insufficient rigidity, making it difficult to generate prestress: Traditional materials become rigid structures after solidification, which cannot form outward rebound force and are difficult to resist external loads.

[0009] (2) Poor energy absorption performance: Under the action of earthquakes or impact loads, traditional materials are difficult to effectively absorb energy, which can easily lead to structural damage.

[0010] (3) Irreversible volume change: Existing foam materials undergo irreversible volume changes after pressurization or curing, and are unable to adapt to pressure requirements in dynamic environments.

[0011] In summary, existing materials have significant deficiencies in flexible rebound, dynamic prestressing, and volume stability, making them difficult to adapt to complex dynamic environments and high-load conditions. Therefore, there is an urgent need for an engineering material with prestressing properties, stable volume after curing, and excellent energy absorption performance to fill the gaps in existing technology and meet the practical needs of engineering reinforcement and support. Summary of the Invention

[0012] The present invention provides a foam slurry with volume expansion and contraction characteristics and a preparation method thereof, aiming to solve the problems existing in common materials such as cement slurry, polymer grouting and foam concrete in engineering construction.

[0013] The present invention provides a foam slurry with volume expansion and contraction characteristics, comprising the following components in parts by weight: 1000 parts of dry slag; 200-300 parts of curing agent; 650-750 parts of water; 1-3 parts of foaming agent; 1-2 parts of anti-dispersant; 2-4 parts of stabilizer.

[0014] As a further improvement of the present invention, the curing agent is a geopolymer-based curing agent, comprising: 50-60 parts of mineral powder, 30-40 parts of cement, and 10-20 parts of water glass.

[0015] As a further improvement of the present invention, the selection of the foaming agent components includes: for high-pressure environments, the foaming agent is a fluorocarbon-based foaming agent; for wet and water-permeable environments, the foaming agent is a silane-modified foaming agent.

[0016] As a further improvement of the present invention, the foam mud with volume expansion and contraction characteristics further includes a component in parts by weight: 1-2 parts of a waterproofing agent, and the composition of the waterproofing agent includes a silane impregnating agent.

[0017] As a further improvement of the present invention, the anti-dispersant is polyvinyl alcohol or sodium carboxymethyl cellulose; the stabilizer is guar gum or nano-silica sol.

[0018] As a further improvement of the present invention, the foam mud with volume expansion and contraction characteristics also includes the following component distribution ratios by weight: 5-8 parts of expansion agent; 3-5 parts of reinforcing agent; 0.5-1.5 parts of anti-cracking reinforcing material; a combination of one or more expansion agents, reinforcing agents, and anti-cracking reinforcing materials is selected for addition.

[0019] As a further improvement of the present invention, the expansion agent is selected from expansion microspheres or polyacrylamide; the reinforcement agent is selected from nano-silicon dioxide or quartz powder; and the anti-cracking reinforcement material is selected from polypropylene fiber.

[0020] The present invention also provides a method for preparing foam slurry with volume expansion and contraction characteristics, comprising the following steps: S1. Preparation of foam mud components: S10. sieve the dry soil to ensure uniform particles; S11 50-60 parts of mineral powder, 30-40 parts of cement and 10-20 parts of water glass are mixed to prepare a geopolymer-based curing agent for standby use; S12. Select clean, impurity-free water for use; S13. Select the foaming agent based on the application scenario: For high-pressure environments, use a fluorocarbon-based foaming agent; for wet and water-permeable environments, use a silane-modified foaming agent; S14. Use polyvinyl alcohol or sodium carboxymethyl cellulose as an anti-dispersion agent; S15. Use guar gum or nano-silica sol as a stabilizer; S2. Mixing of foam mud components: S21 was added to the stirring device 1000 parts of dry soil and 200-300 parts of a geopolymer-based curing agent, stirring at low speed for 1-2 minutes to allow for uniform dispersion; S22 slowly add 650-750 parts of water to the stirring device while increasing the stirring speed so that the slurry gradually takes shape; S23. Add 1-3 parts of foaming agent, 1-2 parts of anti-dispersant, and 2-4 parts of stabilizer to the stirring device in sequence, and continue stirring for 3-5 minutes to form a uniform foam system.

[0021] As a further improvement of the present invention, step S1 further includes the following steps: S16. Select one or more of a waterproofing agent, an expansion agent, a reinforcing agent, and an anti-cracking reinforcing material as an additive according to the application scenario; wherein a silane impregnating agent is selected as the waterproofing agent; expandable microspheres or polyacrylamide are selected as the expansion agent; nano-silica or quartz powder is selected as the reinforcing agent; and polypropylene fiber is selected as the anti-cracking reinforcing material; The step S2 further comprises the following steps: S24 add 5-8 parts of expander and 3-5 parts of enhancer to the stirring device and continue stirring for 5 minutes to allow the expander and enhancer to be evenly distributed; S25. Add 1-2 parts of waterproofing agent and 0.5-1.5 parts of anti-cracking reinforcing material into the stirring device and mix at low speed for 2 minutes to complete the preparation of foam mud.

[0022] As a further improvement of the present invention, after the foam mud is prepared, the following steps are further included: S3. Foam mud detection: S31. Use a wet density meter to test the wet density of the foamed mud to ensure that it meets the set wet density requirements; S32. Conduct fluidity and expansion rate tests and adjust the slurry state to the optimal working conditions; S4. Pressure application: A high-pressure pump is used to inject foam slurry into the target area while applying a predetermined pressure to create a rebound force in the closed-cell bubbles. S5. Curing: Curing is carried out under a predetermined pressure to maintain the humidity of the foam mud until the foam mud solidifies and the volume stabilizes.

[0023] The beneficial effects of the present invention are: the foam mud with volume expansion and contraction characteristics has a stable volume after solidification, and due to the existence of internal closed-cell tough bubbles, it can be compressed for transportation, filled, and other operations in the unsolidified stage. It is suitable for engineering scenarios such as foundation reinforcement, tunnel support, seismic-resistant structures, cavity filling, and underground plugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a state diagram of the foam mud solidification product with volume expansion and contraction characteristics of the present invention before pressurization, during pressurization, and after pressure relief; Figure 2 It is a bar graph showing the volume, compression rate and pressure of the foam mud solidification product with volume expansion and contraction characteristics before pressurization, during pressurization and after pressure relief. DETAILED DESCRIPTION

[0025] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0026] The foam slurry with volume expansion and contraction characteristics of the present invention comprises the following components in parts by weight: 1000 parts of dry slag; 200-300 parts of curing agent; 650-750 parts of water; 1-3 parts of foaming agent; 1-2 parts of anti-dispersant; 2-4 parts of stabilizer; 5-8 parts of expansion agent; 3-5 parts of reinforcing agent; 1-2 parts of waterproofing agent; 0.5-1.5 parts of anti-cracking reinforcing material.

[0027] Among them, dry slag, curing agent, water, foaming agent, anti-dispersant and stabilizer are the main materials of foam mud with volume expansion and contraction characteristics, while expansion agent, reinforcing agent, waterproofing agent and anti-cracking reinforcing material are additional added materials that can be selected individually or in combination according to the usage scenario.

[0028] The curing agent is a geopolymer-based curing agent, including: 50-60 parts of mineral powder, 30-40 parts of cement, and 10-20 parts of water glass.

[0029] The selection of foaming agent ingredients includes: for high-pressure environments, fluorocarbon-based foaming agents are used, which are suitable for high-pressure conditions and complex load environments, and have high stability and high temperature resistance; for humid and water-seeping environments, silane-modified foaming agents are used, which are suitable for environments with high humidity or strong groundwater penetration, and provide excellent water resistance and durability. Waterproofing agents include silane impregnants. These are optional additives, depending on the environment in which the foam slurry will be used. For example, in wet and water-permeable environments, a waterproofing agent can be added to enhance the foam slurry's water resistance. The small molecular structure of silane impregnants allows them to penetrate deep into the substrate, forming a durable waterproof layer with a long service life. The material is highly durable and environmentally friendly.

[0030] Anti-dispersion agents include polyvinyl alcohol (PVA) or sodium carboxymethyl cellulose (CMC). PVA dissolves rapidly in water and forms a uniform protective film, effectively encapsulating particles and reducing dispersion. It also exhibits excellent bonding properties and temperature stability. CMC exhibits strong hydrophilicity and thickening properties, significantly increasing system viscosity and inhibiting particle settling and segregation, with outstanding performance under alkaline conditions. Both are environmentally friendly and biodegradable, and are highly compatible with other additives, synergistically enhancing anti-dispersion effects.

[0031] Guar gum or nano-silica sol is used as a stabilizer. Guar gum has excellent thickening and suspending capabilities, effectively preventing particle sedimentation and phase separation by forming a three-dimensional network structure. It is also highly biocompatible, biodegradable, and low-cost. Nano-silica sol, with its nano-sized silica particles' high specific surface area and surface activity, significantly improves system stability while also imparting enhanced mechanical strength, high-temperature resistance, and transparency to the material.

[0032] Expansive agents, such as expandable microspheres (such as Expancel) or polyacrylamide (PAM), are used to increase the volume of the foamed mud by introducing air bubbles or expandable microspheres into the material. This allows the foamed mud to expand and rebound during pressurization or curing, enhancing the material's elasticity and stability. Expansive agents are used in applications requiring volume expansion, such as foundation reinforcement, cavity filling, or underground plugging.

[0033] Nano-silica (SiO2) or quartz powder is used as a reinforcing agent to enhance the mechanical properties of the foam slurry, increasing its strength and wear resistance, and improving its load-bearing capacity under high-pressure environments. Reinforcements are used in applications requiring high-strength support, such as tunnel support and structural reinforcement.

[0034] Polypropylene fiber is used as the crack-resistant reinforcement material. Adding fiber to the slurry effectively disperses stress and reduces cracks caused by external forces after curing. This crack-resistant reinforcement material is used in situations where crack propagation must be prevented, such as in earthquake-resistant structures and earthquake reinforcement projects.

[0035] The present invention also provides a method for preparing foam mud with volume expansion and contraction characteristics, which is characterized by comprising the following steps: S1. Preparation of foam mud components: S10. sieve the dry soil to ensure uniform particles; S11 curing agent in accordance with the geopolymer-based formula, respectively, 50-60 parts of mineral powder, 30-40 parts of cement and 10-20 parts of water glass are mixed to prepare a geopolymer-based curing agent standby; S12. Select clean, impurity-free water for use; S13. Select the appropriate foaming agent based on the application scenario: For high-pressure environments, use a fluorocarbon-based foaming agent; for wet and water-permeable environments, use a silane-modified foaming agent; S14. Use polyvinyl alcohol (PVA) or sodium carboxymethyl cellulose (CMC) as an anti-dispersion agent; S15. Use guar gum or nano-silica sol as a stabilizer; S16. Select one or more combinations of waterproofing agents, expansion agents, reinforcing agents, and anti-cracking reinforcing materials as additives based on the application scenario; among them, select silane impregnating agent as waterproofing agent; select expandable microspheres (such as Expancel) or polyacrylamide (PAM) as expansion agent; select nano-silica (SiO2) or quartz powder as reinforcing agent; select polypropylene fiber as anti-cracking reinforcing material.

[0036] S2. Mixing of foam mud components: S21. Add 1000 parts of dry soil and 200-300 parts of geopolymer-based curing agent to a stirring device and stir at low speed for 1-2 minutes to ensure uniform dispersion; S22 slowly add 650-750 parts of water to the stirring device while increasing the stirring speed to ensure that the slurry gradually takes shape; S23. Sequentially add 1-3 parts of foaming agent (a fluorocarbon-based foaming agent or a silane-modified foaming agent is added according to the application scenario), 1-2 parts of anti-dispersant, and 2-4 parts of stabilizer to the stirring device, and continue stirring for 3-5 minutes to form a uniform foam system; S24. Add 5-8 parts of expander (optional) and 3-5 parts of enhancer (optional) to the stirring device and continue stirring for 5 minutes to ensure uniform distribution of expander and enhancer. S25. Finally, add 1-2 parts of waterproofing agent (optional) and 0.5-1.5 parts of anti-cracking reinforcement material (optional) into the stirring device and mix at a low speed for 2 minutes to complete the preparation of the foam mud.

[0037] The order of addition and the intensity of stirring determine the uniform distribution of the components in the slurry. First, add the dry materials (such as dry slag and curing agent) and stir at a low speed to help disperse the base. Then, slowly add the water and increase the stirring speed to ensure a well-flowing slurry.

[0038] Adding foaming agents, anti-dispersants, stabilizers, etc. after forming the basic slurry can ensure that the slurry forms a stable foam system under dynamic stirring, while avoiding premature reaction or agglomeration between components.

[0039] The foaming agent needs to be added to the fully dispersed slurry system to form uniform bubbles to provide a density reduction effect.

[0040] The order and time of adding anti-dispersants and stabilizers (usually added after the foaming agent) help maintain the rheological properties of the slurry and the stability of the foam, preventing the bubbles from breaking or collapsing during stirring.

[0041] Expansive and reinforcing agents are usually added after the foam system is formed. Prolonging the stirring time can fully exert the expansion and reinforcing effects. This process also directly affects the compressive strength of the slurry and its rebound properties after curing.

[0042] Waterproofing agents and crack-resistant reinforcements are generally added at the final stage to avoid excessive shearing or damage during the intense mixing process. These components directly affect the durability and crack resistance of the material after curing.

[0043] After the foam mud preparation is completed, the following steps are also included: S3. Foam mud detection: S31. Use a wet density meter to test the wet density of the foam mud to ensure that the foam mud meets the set wet density requirements; the design requirement for wet density is generally 0.5~1.3g / cm 3 , thereby ensuring the uniformity and stability of the material. If the wet density does not meet the requirements after measurement, the relative proportions of the foaming agent, curing agent, and water can be adjusted within the specified range. The wet density directly affects the fluidity of the slurry during subsequent construction and its mechanical properties after curing.

[0044] S32. Conduct fluidity and expansion rate tests and adjust the slurry state to the optimal working conditions.

[0045] The fluidity test primarily ensures the slurry flows smoothly during construction, avoiding uneven grouting due to excessive viscosity or insufficient fluidity. A standard funnel is used to measure flow time, with 35-45 seconds indicating optimal fluidity. The expansion rate test ensures the material can provide the expected expansion effect in a dynamic environment, thereby meeting the requirements of application scenarios (such as crack resistance or rebound performance). The optimal expansion rate is generally 5%-10%.

[0046] The process of adjusting the slurry to optimal working conditions primarily involves adjusting the ratio of water to curing agent to alter the slurry's viscosity or fluidity; adjusting the amount of foaming agent as needed to ensure the slurry's density and resilience meet standards; and, if performance deviates from target values ​​during testing, adjusting the performance by adding or subtracting appropriate components. The ultimate goal of these operations is to ensure that the slurry, after curing, possesses the desired volume expansion and contraction characteristics, as well as other physical properties such as compressive strength and volume stability.

[0047] After the foam mud is prepared according to the component ratio, the following steps are also included: S4. Pressure application: Use a high-pressure pump to inject foam slurry into the target area while applying a predetermined pressure to create a rebound force within the closed-cell bubbles. The foam slurry generates this rebound force after pressure is applied. The pressure needs to be adjusted based on project requirements but should not exceed 500 kPa to avoid overpressure that could cause bubble rupture or excessive compression.

[0048] S5. Curing: Curing is performed at a predetermined pressure, maintaining the foam slurry's humidity until the volume stabilizes after solidification. The curing environment must maintain an appropriate humidity (generally 80%-90%). This can be maintained by covering with a damp cloth, spraying with water, or using a wet curing film. Avoid excessive shrinkage during curing due to rapid evaporation of water, which can cause cracks or performance degradation. The curing area temperature is generally controlled between 10°C and 30°C to avoid excessively high or low temperatures that could affect the material's chemical reactions and curing speed. Curing time varies depending on the actual environment and material mix, but is typically 6-48 hours. After curing is complete, gradually release the applied pressure to avoid sudden decompression that could damage the slurry's internal structure. Ensure a rebound rate of at least 95% to confirm that the slurry's volume is essentially stable after solidification. After curing, the closed-cell bubbles within the finished product generate an outward rebound force, providing a stable prestressing effect.

[0049] This foam mud has the following characteristics: by applying pressure before solidification, the closed-cell bubbles inside the mud form initial rebound force, and the volume can be restored after the pressure is released; when the set force is reached, the volume no longer shrinks, and the volume is stable after solidification; after the mud solidifies, the closed-cell bubbles generate outward rebound force, providing an effect similar to prestressed concrete.

[0050] like Figure 1 As shown in FIG. 3 , the compression test data of the finished product of the foam mud after solidification of the present invention are as follows: before pressurization: the volume is 150 ml; during pressurization (maximum pressure 500 kPa): the volume shrinks to 100 ml; after pressure relief: the volume recovers to 148 ml, and the rebound rate reaches 98.7%.

[0051] Pressure-volume curve analysis: Figure 2As shown in the figure, as the pressure increases, the volume of the foam mud product gradually decreases, and after reaching the maximum compression, the volume tends to stabilize. After pressure relief, the foam mud exhibits good rebound performance and can return to a state close to its initial volume.

[0052] Data comparison: The rebound rate of traditional foam concrete is 80%; the rebound rate of the foam slurry of the present invention is 98.7%.

[0053] Strength test after curing: The compressive strength of the foamed mud of the present invention reaches 5.8 MPa after curing for 28 days, which is far higher than the 3.2 MPa of ordinary foamed concrete.

[0054] The following two embodiments illustrate the preparation process of the foam mud of the present invention in a high-pressure environment and a humid environment respectively.

[0055] Example 1: Prestressed foundation reinforcement (high-pressure environment).

[0056] a1. Material selection and ratio: Dry slag soil: 1000 parts, choose dry slag soil with uniform particle size and no organic impurities.

[0057] Geopolymer-based curing agent: Mineral powder: 60 parts, provides basic strength support. Cement: 40 parts, enhances the hardness and stability of the material. Water glass: 20 parts, acts as an initiator for the geopolymer reaction.

[0058] Water: 700 parts, to ensure the slurry has good fluidity.

[0059] Foaming agent: Use 2 parts of fluorocarbon-based foaming agent, which has high stability and is suitable for high-pressure foundation reinforcement environment.

[0060] Expansion agent: 6 parts, polyacrylamide (PAM) is selected to provide a certain degree of expansion.

[0061] Anti-dispersant: 1.5 parts, polyvinyl alcohol (PVA) is selected.

[0062] Reinforcement agent: 4 parts, nano silicon dioxide (SiO2) is used.

[0063] Stabilizer: 2 parts, choose guar gum.

[0064] Anti-cracking reinforcement material: 1 part, polypropylene fiber.

[0065] a2.Production process: a21.Material Mixing: In the mixing equipment, first add dry slag and geopolymer-based curing agent and stir at low speed for 2 minutes; Slowly add water while gradually increasing the stirring speed to form a flowing and uniform slurry; Add foaming agent, expander and enhancer in sequence and continue stirring for 5 minutes; Finally, add anti-dispersant and anti-cracking reinforcing material and stir at low speed for 2 minutes to complete the slurry preparation.

[0066] a22. Slurry testing: Wet density test: Use a wet density meter to measure the slurry density and control it at 1.2-1.3g / cm 3 ; Fluidity test: Use a standard funnel to test the flow time and ensure it is within 35-45 seconds.

[0067] a3. Construction technology: a31. Site survey: Conduct geological survey of the foundation to determine the grouting location and depth.

[0068] a32. Grouting equipment preparation: Use high-pressure grouting equipment to inject foam slurry into the target area at a design pressure of 500kPa.

[0069] a33. Pressure application: Through continuous high-pressure pumping, closed-cell bubbles are formed and initial pressure is applied.

[0070] a34. Solidification and curing: After grouting is completed, maintain pressure for 24 hours to allow the slurry to solidify. After solidification, the closed-cell bubbles provide resilience, forming a prestressed support layer.

[0071] a4. Effect detection: a41. Prestressing effect: The pressure distribution within the support layer is measured using a pressure sensor. The pressure distribution within the support layer is uniform, with the maximum pressure concentrated in the center area, ensuring balanced load transfer and effective stress distribution.

[0072] a42. Rebound performance test: Using pressure-volume curve analysis, the rebound rate reaches more than 98%.

[0073] a43. Foundation strength test: The compressive strength of the supporting layer after curing is 5.8MPa.

[0074] Example 2: Underground plugging (humid environment).

[0075] b1. Material selection and ratio: Dry soil: 1000 parts.

[0076] Geopolymer-based curing agent: Mineral powder: 50 parts, Cement: 35 parts, Water glass: 15 parts.

[0077] Water: 750 parts.

[0078] Foaming agent: Use 2 parts of silane-modified foaming agent to adapt to high humidity and water penetration environment.

[0079] Expanding agent: 8 parts of polyacrylamide.

[0080] Reinforcement agent: 5 parts of nano silicon dioxide.

[0081] Stabilizer: 2 parts guar gum.

[0082] Anti-dispersion agent: 1 part of polyvinyl alcohol.

[0083] b2.Production process: b21. Material mixing: In the mixing equipment, first add dry slag and geopolymer-based curing agent and stir at low speed for 2 minutes; Slowly add water while gradually increasing the stirring speed to form a flowing and uniform slurry; Add foaming agent, expander and enhancer in sequence and continue stirring for 5 minutes; Finally, add anti-dispersant and anti-cracking reinforcing material and stir at low speed for 2 minutes to complete the slurry preparation.

[0084] b22. Slurry testing: Wet density test: Use a wet density meter to measure the slurry density and control it at 1.2-1.3g / cm 3 ; Fluidity test: Use a standard funnel to test the flow time and ensure it is within 35-45 seconds.

[0085] b3. Construction technology: b31. Investigation of the sealing area: Determine the location of underground cracks and cavities.

[0086] b32. Foam slurry injection: Inject the slurry into the target area through a low-pressure grouting pump.

[0087] b33. Pressure control and curing: Maintain pressure for 48 hours to ensure the slurry cures.

[0088] b4. Effect detection: b41. Permeability: After curing, the material's anti-permeability coefficient reaches 10 -8 cm / s.

[0089] b42. Stability: There is no obvious leakage or settlement in the sealed area.

[0090] b43. Rebound rate test: The material rebound rate reaches more than 95%.

[0091] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A foam mud with volume expansion and contraction characteristics, characterized in that: The composition comprises the following weight parts: 1000 parts of dry soil; 200-300 parts of curing agent; 650-750 parts water; 1-3 parts of foaming agent; 1-2 parts of anti-dispersant; 2-4 parts of stabilizer.

2. The foam mud with volume expansion and contraction characteristics according to claim 1, characterized in that: The curing agent is a geopolymer-based curing agent, which includes 50-60 parts of mineral powder, 30-40 parts of cement, and 10-20 parts of water glass.

3. The foam mud with volume expansion and contraction characteristics according to claim 1, characterized in that: The selection of the foaming agent components includes: for high-pressure environments, the foaming agent is a fluorocarbon-based foaming agent; for wet and water-permeable environments, the foaming agent is a silane-modified foaming agent.

4. The foam mud with volume expansion and contraction characteristics according to claim 1, characterized in that: The invention also includes components in parts by weight: 1-2 parts of a waterproofing agent, wherein the ingredients of the waterproofing agent include a silane impregnating agent.

5. The foam mud with volume expansion and contraction characteristics according to claim 1, characterized in that: The anti-dispersant is polyvinyl alcohol or sodium carboxymethyl cellulose; the stabilizer is guar gum or nano-silica sol.

6. The foam mud with volume expansion and contraction characteristics according to claim 1, characterized in that: Also includes the following weight ratio: 5-8 parts of expansion agent; 3-5 parts of enhancer; 0.5-1.5 parts of anti-cracking reinforcement material; A combination of one or more expansion agents, reinforcing agents, and anti-cracking reinforcing materials is selected for addition.

7. The foam mud with volume expansion and contraction characteristics according to claim 6, characterized in that: The expansion agent is selected from expansion microspheres or polyacrylamide; the reinforcing agent is selected from nano silicon dioxide or quartz powder; and the anti-cracking reinforcing material is selected from polypropylene fiber.

8. A method for preparing foam mud with volume expansion and contraction characteristics, characterized in that: The following steps are involved: S1. Preparation of foam mud components: S10. sieve the dry soil to ensure uniform particles; S11 50-60 parts of mineral powder, 30-40 parts of cement and 10-20 parts of water glass are mixed to prepare a geopolymer-based curing agent for standby use; S12. Select clean, impurity-free water for use; S13. Select the foaming agent based on the application scenario: For high-pressure environments, use a fluorocarbon-based foaming agent; for wet and water-permeable environments, use a silane-modified foaming agent; S14. Use polyvinyl alcohol or sodium carboxymethyl cellulose as an anti-dispersion agent; S15. Use guar gum or nano-silica sol as a stabilizer; S2. Mixing of foam mud components: S21 was added to the stirring device 1000 parts of dry soil and 200-300 parts of a geopolymer-based curing agent, stirring at low speed for 1-2 minutes to allow for uniform dispersion; S22 slowly add 650-750 parts of water to the stirring device while increasing the stirring speed so that the slurry gradually takes shape; S23. Add 1-3 parts of foaming agent, 1-2 parts of anti-dispersant, and 2-4 parts of stabilizer to the stirring device in sequence, and continue stirring for 3-5 minutes to form a uniform foam system.

9. The method for preparing foam mud with volume expansion and contraction characteristics according to claim 8, characterized in that: The step S1 further comprises the following steps: S16. Select one or more of a waterproofing agent, an expansion agent, a reinforcing agent, and an anti-cracking reinforcing material as an additive according to the application scenario; wherein a silane impregnating agent is selected as the waterproofing agent; expandable microspheres or polyacrylamide are selected as the expansion agent; nano-silica or quartz powder is selected as the reinforcing agent; and polypropylene fiber is selected as the anti-cracking reinforcing material; The step S2 further comprises the following steps: S24 add 5-8 parts of expander and 3-5 parts of enhancer to the stirring device and continue stirring for 5 minutes to allow the expander and enhancer to be evenly distributed; S25. Add 1-2 parts of waterproofing agent and 0.5-1.5 parts of anti-cracking reinforcing material into the stirring device and mix at low speed for 2 minutes to complete the preparation of foam mud.

10. The method for preparing foam mud with volume expansion and contraction characteristics according to claim 8, characterized in that: After the foam mud preparation is completed, the following steps are also included: S3. Foam mud detection: S31. Use a wet density meter to test the wet density of the foamed mud to ensure that it meets the set wet density requirements; S32. Conduct fluidity and expansion rate tests and adjust the slurry state to the optimal working conditions; S4. Pressure application: A high-pressure pump is used to inject foam slurry into the target area while applying a predetermined pressure to create a rebound force in the closed-cell bubbles. S5. Curing: Curing is carried out under a predetermined pressure to maintain the humidity of the foam mud until the foam mud solidifies and the volume stabilizes.

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