Sponge soil forming agent, sponge soil and preparation method of sponge soil

Abstract

The invention relates to a sponge soil forming agent, sponge soil and a sponge soil preparation method. Belongs to the technical field of ecological environment construction, and particularly relates to soil improvement under the scenes of mine restoration, slope protection and greening, desertification control and the like. The sponge soil forming agent is prepared from the following materials in parts by weight: 20-50 parts of an organic polymer material, 20-40 parts of a foaming agent, 10-30 parts of a cross-linking agent, 1-40 parts of a toughening agent, 10-30 parts of a pH regulator and 0.5-2 parts of a surfactant. The spongy soil prepared on the basis of the technology has a highly-crosslinked and interpenetrating spongy three-dimensional porous structure and an adhesive characteristic, has high water retention, air permeability and rain wash resistance, and can absorb and store a large amount of water. On one hand, water can be conserved, the soil stability and erosion resistance are enhanced, and the risks of soil hardening and water and soil loss are effectively reduced; on the other hand, sufficient oxygen can be provided for plant roots, respiration and growth and development of the roots are facilitated, and restoration and improvement of the ecological environment are assisted.

Description

Technical Field

[0001] The present invention relates to the field of ecological environment construction, specifically covering soil improvement technologies in scenarios such as mine restoration, slope protection and greening, and desertification control. In particular, it relates to a sponge soil forming agent, sponge soil, and a method for preparing sponge soil. Background Art

[0002] As China's economic development model steadily moves from the high-speed growth stage to the stable growth stage, the concept of environmental protection has become increasingly deeply rooted in people's hearts. For the mountain wounds left by open-pit mine exploitation and large-scale mountainous engineering construction, implementing ecological restoration is not only an urgent need to improve the ecological environment but also an inevitable choice for sustainable development. However, in the current actual situation, the ecological restoration work for high and steep mountain wounds faces many challenges. There is no broad and unified understanding at the conceptual level, and there are many bottlenecks that urgently need to be broken through at the technical level.

[0003] Sponge soil technology, as an innovative technology in the field of soil improvement and utilization, brings new ideas and solutions to slope ecological restoration. In the process of slope ecological restoration and recovery, effectively resisting water erosion is a crucial core element. Water erosion not only causes a large amount of loss of slope soil, damages the existing vegetation, but also poses a serious threat to the stability of the slope, thereby hindering the ecological environment restoration process.

[0004] However, it is worth noting that traditional soil improvers have obvious limitations in practical applications. They often struggle to balance anti-erosion, water retention, and air permeability, easily leading to soil erosion or soil compaction, which affects the growth and development of plant roots. Although existing technologies have certain performance advantages in some aspects, either their anti-rain erosion performance is insufficient, or they are prone to compaction and not conducive to plant growth, or they are costly and have poor environmental compatibility, and may cause secondary pollution to the soil and surrounding environment during the degradation process. In addition, existing technologies or forming agents are not ideal in enhancing the long-term stability of soil structure and are difficult to meet the requirements of slope ecological restoration for the long-term stability performance of soil.

[0005] In summary, sponge soil forming technology provides a new approach to solving the water erosion problem in slope ecological restoration and improving the comprehensive performance of soil with its unique advantages, and has broad application prospects and important practical significance.

[0006] The invention patent with the application number 201710036479.8 discloses a composite material for treating soil heavy metal pollution. The composite material has a porous sponge structure and is prepared from raw materials such as 5 - 10 parts by weight of wood cellulose, 10 - 30 parts of hydroxy acid, 20 - 40 parts of polyvinyl alcohol, 10 - 25 parts of amorphous olefin copolymer, 10 - 20 parts of azodicarbonamide, 10 - 20 parts of sodium carbonate, 0.5 - 1.0 part of diisopropylbenzene peroxide, 3 - 5 parts by weight of sodium citrate, 1 - 3 parts of initiator, etc. Although the composite material has good removal effect on heavy metal ions, the steps for treating soil heavy metal pollution are simple and the treatment efficiency is high, which is suitable for large-scale application in the treatment of soil heavy metal pollution. However, objectively analyzed from the perspective of ecological restoration, it may not fully meet the comprehensive requirements for water retention, air permeability and long-term stability of the soil in ecological restoration, and it has not been specifically optimized for special environments such as high and steep mountain slopes in ecological restoration, so there are certain limitations.

[0007] Therefore, researching and developing a sponge soil forming agent with high water absorption, water retention, air permeability and rain erosion prevention performance is a work of great significance and urgent to be solved, which has a positive impact on the country and the people. Summary of the Invention

[0008] Aiming at the deficiencies of the prior art, the present invention provides a sponge soil forming agent, a sponge soil using the sponge soil forming agent, and a preparation method of the sponge soil. The prepared sponge soil has high water absorption, water retention, air permeability and rain erosion prevention performance.

[0009] The technical solution adopted by the present invention is as follows: A sponge soil forming agent, in parts by weight, is composed of materials of the following components: Organic polymer material: 20 - 50 parts; Foaming agent: 20 - 40 parts; Crosslinking agent: 10 - 30 parts; Toughening agent: 1 - 40 parts, and the toughening agent uses aqueous latex; pH regulator: 10 - 30 parts; Surfactant: 0.5 - 2 parts.

[0010] The sponge soil forming agent further includes plant fiber: 1 - 40 parts.

[0011] The described sponge soil forming agent uses an organic polymer material as the basic reaction material, and uses one of sodium polyacrylate, sodium polyvinyl sulfonate, sodium polystyrene sulfonate, sodium alginate or anionic polyacrylamide, or a mixture of any two or three of them. The organic polymer material reacts with a foaming agent, a crosslinking agent, a toughening agent, a pH regulator and a surfactant to form a sponge soil with a "sponge-like" three-dimensional network porous structure.

[0012] For the described sponge soil forming agent, the foaming agent uses one or more of calcium carbonate, barium carbonate, sodium carbonate or sodium bicarbonate. Among them, the metal ions generated by the reaction of calcium carbonate or barium carbonate with the pH regulator can also participate in the crosslinking reaction.

[0013] For the described sponge soil forming agent, the crosslinking agent uses one or more of calcium chloride, magnesium chloride, zinc chloride, barium chloride or ferric chloride. The pH regulator uses one or more of dilute hydrochloric acid solution, dilute acetic acid solution or dilute phosphoric acid solution.

[0014] For the described sponge soil forming agent, the surfactant uses a small molecule surfactant alkyl sulfonate (such as sodium dodecyl sulfonate, sodium hexadecyl sulfonate, etc.), alkyl benzene sulfonate (such as sodium dodecyl benzene sulfonate, etc.), or a macromolecule surfactant (such as polyethylene glycol, etc.).

[0015] A sponge soil uses the above-described sponge soil forming agent, adds 20 - 500 parts by weight of soil or soil matrix material, and is made into a "sponge-like" three-dimensional network porous structure through a crosslinking reaction.

[0016] The soil matrix material includes 14 - 16% wood fiber, 14 - 16% decomposed corn cob, 9 - 11% decomposed sheep manure, and the balance is guest soil; the guest soil contains 65 - 70% silt, 27.5 - 32.5% sand and <2.5% clay.

[0017] The preparation method of the sponge soil as described above includes the following steps: Step S1: First, according to the weight ratio, take the foaming agent, crosslinking agent, toughening agent and soil, add water to dissolve, and stir well to form a uniform aqueous dispersion liquid a; Step S2: Mix the corresponding weight ratio of the organic polymer material with water and stir well to obtain the basic reaction material b; Step S3: Mix the aqueous dispersion liquid a prepared in Step S1 with the basic reaction material b prepared in Step S2, and stir well to obtain the basic spraying substrate material c; Step S4: Dissolve the corresponding weight ratio of the pH regulator and surfactant material in water to prepare a spraying aqueous solution d, and spray the prepared aqueous solution d onto the surface of the base layer formed by spraying the spraying substrate material c onto the slope surface; The organic polymer material reacts with a foaming agent, a cross-linking agent, a toughening agent, a pH regulator and a surfactant to form a sponge soil with a "sponge-like" three-dimensional network porous structure.

[0018] In the preparation method of the sponge soil, in step S1, plant fibers are added in corresponding weight parts according to needs and stirred evenly to increase the soil viscosity.

[0019] Advantages of the invention: 1. The sponge soil forming agent and the sponge soil of the present invention form a porous system with a "sponge-like" three-dimensional network structure through a cross-linking agent, which has high water retention and air permeability, effectively improving the water retention rate and water absorption rate. The good soil structure and sufficient supply of water and oxygen enable plant roots to better stretch and take root, absorb more oxygen, water and nutrients, thereby promoting the growth of the above-ground part of the crop and improving the yield and quality of the crop. Enable the crop to still maintain a relatively good growth state under adverse environmental conditions such as drought and flood, and improve the stress resistance and adaptability of the crop.

[0020] 2. The sponge soil forming agent of the present invention uses all environmentally friendly materials, is environmentally friendly, and has good biocompatibility of the materials, which can effectively promote plant growth. In urban parks, road greening, etc., it can effectively conserve water sources, improve the survival rate and growth quality of greening plants, and at the same time contribute to the collection and utilization of urban rainwater. The sponge soil prepared based on this technology plays a significant role in the above ecological environment construction scenarios. On the one hand, it can conserve water, enhance the soil stability and anti-erosion ability, and effectively reduce the risks of soil compaction and soil erosion; on the other hand, it can provide sufficient oxygen for plant roots, which is very beneficial to the respiration and growth and development of roots, and helps the restoration and improvement of the ecological environment.

[0021] 3. The sponge soil forming agent and the sponge soil of the present invention add plant fibers, which can play a synergistic effect: the beneficial bacteria in the plant fibers continuously release nutrients, promoting the formation of high-quality soil aggregate structures. Making the soil particles form stable aggregates can enhance the soil stability and anti-erosion ability, and reduce the risks of soil compaction and soil erosion. The improvement of the soil structure and the enhancement of the crop stress resistance improve the soil fertility and fertilizer retention ability.

[0022] 4. The preparation method of the sponge soil forming agent and the sponge soil of the present invention has a simple process. In the first step, a soil matrix is added, and each material is carefully formulated, and complex reactions occur between them. Finally, a porous system sponge soil with a highly cross-linked and interpenetrating "sponge-like" three-dimensional network structure is prepared, making the soil loose and porous, with high water retention and air permeability. It has porous and adhesive properties, has high water retention, air permeability and rainwater erosion resistance, can absorb and store a large amount of water, and can provide sufficient oxygen for plant roots, which is beneficial to the respiration and growth and development of roots. Description of the Drawings

[0023] Figure 1 The figure shows the state of the sponge soil prepared in Experimental Example 7 simulating attachment to a slope; Figure 2 The figure shows the natural air-dried state of the sponge soil prepared in Experimental Example 7; Figure 3 The figure shows the state of the sponge soil prepared in Experimental Example 8 simulating attachment to a slope; Figure 4 The figure shows the effect after the sponge soil prepared in Experimental Example 8 is formed in a dry state; Figure 5 The figure shows the state effect of the sponge soil prepared in Experimental Example 9 simulating attachment to a slope; Figure 6 The figure shows the sensory effect of the sponge soil prepared in Experimental Example 9 in a container in the formed state; Figure 7(a) shows the water absorption test curve of the sponge soil prepared in Experimental Example 9; Figure 7(b) shows the water retention test curve of the sponge soil prepared in Experimental Example 9 at room temperature in summer; Figure 8 The figure shows the good growth trend of plants in the sponge soil prepared in Examples 7 - 9. Detailed Embodiments

[0024] To make the technical concept and advantages for realizing the invention purpose of the present invention clearer and more understandable, the technical solutions of the present invention will be further described in detail below with reference to the drawings. It should be understood that the following embodiments are only for explaining and illustrating the preferred embodiments of the present invention, and should not be regarded as and do not constitute a limitation to the scope of patent protection required by the present invention.

[0025] The sponge soil forming agent of the present invention uses organic polymer materials as the basic reaction materials, and one of sodium polyacrylate, sodium polyvinyl sulfonate, sodium polystyrene sulfonate, sodium alginate or anionic polyacrylamide can be used, or any two or three of these materials can be mixed. The foaming agent uses one or more of calcium carbonate, barium carbonate, sodium carbonate or sodium bicarbonate. Among them, the metal ions generated by the reaction of calcium carbonate or barium carbonate with the pH regulator can also participate in the cross-linking reaction. The cross-linking agent uses one or more of calcium chloride, magnesium chloride, zinc chloride, barium chloride or ferric chloride. The pH regulator uses one or more of dilute hydrochloric acid solution, dilute acetic acid solution or dilute phosphoric acid solution. The surfactant uses small molecule surfactants such as alkyl sulfonates (such as sodium dodecyl sulfonate, sodium hexadecyl sulfonate, etc.), alkyl benzene sulfonates (such as sodium dodecyl benzene sulfonate, etc.), or uses macromolecule surfactants (such as polyethylene glycol, etc.). The organic polymer material reacts with the foaming agent, cross-linking agent, toughening agent, pH regulator and surfactant to generate a sponge soil with a "sponge-like" three-dimensional network porous structure. The toughening agent uses aqueous chloroprene latex.

[0026] Example 1 The raw material ratio (mass / weight percentage) of the sponge soil forming agent in this example is as follows: 20 parts of sodium polyacrylate, 20 parts of foaming agent, 10 parts of cross-linking agent, 2 parts of toughening agent; 10 parts of pH regulator, 1 part of auxiliary additive (surfactant).

[0027] Example 2 The raw material ratio (mass / weight parts) of the sponge soil forming agent in this example is as follows: Organic polymer material: 50 parts; foaming agent: 40 parts; cross-linking agent: 20 parts; toughening agent: 20 parts; pH regulator: 10 parts; surfactant: 2 parts.

[0028] Example 3 The raw material ratio (mass / weight parts) of the sponge soil forming agent in this example is as follows: Organic polymer material: 50 parts; foaming agent: 20 parts; cross-linking agent: 30 parts; toughening agent: 40 parts; pH regulator: 20 parts; surfactant: 2 parts.

[0029] Example 4 The raw material ratio (mass / weight parts) of the sponge soil forming agent in this example is as follows: Organic polymer material: 30 parts; foaming agent: 30 parts; cross-linking agent: 20 parts; toughening agent: 1 part; pH regulator: 10 parts; surfactant: 1 part.

[0030] Example 5 The raw material ratio (mass / weight parts) of the sponge soil forming agent in this example is as follows: Organic polymer material: 40 parts; foaming agent: 20 parts; crosslinking agent: 30 parts; toughening agent: 10 parts; pH regulator: 30 parts; surfactant: 0.5 part.

[0031] For the sponge soil forming agent described in each of the above embodiments, plant fibers can also be added: the addition amount of plant fibers is 1 - 40 parts. Adding plant fibers in the corresponding weight ratio according to needs can increase the soil viscosity.

[0032] Example 6 This example is about using the sponge soil forming agent described above, adding 20 - 500 times the amount of soil or soil matrix material, and making a "sponge-like" three-dimensional network porous structure sponge soil through crosslinking reaction.

[0033] The soil matrix material includes 14 - 16% wood fiber, 14 - 16% decomposed corn cob, 9 - 11% decomposed sheep manure, and the balance is the guest soil; the guest soil contains 65 - 70% silt, 27.5 - 32.5% sand, and <2.5% clay.

[0034] Example 7 This example is about a method for preparing sponge soil using a sponge soil forming agent. Sponge soil forming agent: 30% sodium alginate, 25% sodium carbonate, 20% magnesium chloride, 20% pH regulator (acetic acid), 3% toughening agent (aqueous chloroprene latex), 2% surfactant (polyethylene glycol); The preparation method of the sponge soil forming agent in this example is as follows: Step S1: Dissolve 330 g of sodium carbonate (foaming agent), 40 g of toughening agent (aqueous chloroprene latex), and 260 g of magnesium chloride (crosslinking agent) in 40 kg of water, and at the same time add 35 kg of soil, and stir well to form a uniform aqueous dispersion a (when using plant fibers, take an appropriate amount according to the ratio and add them at the same time, and plant fibers are not added in this example); Step S2: Mix 400 g of sodium alginate with water to obtain the basic reaction material b; Step S3, mix the aqueous dispersion a prepared in Step S1 with the basic reaction material b prepared in Step S2 to obtain the basic spray seeding matrix material c; let the system stand and react for a period of time to form a shape; Step S4, mix 260 g of acetic acid with 4 kg of water to make a dilute acetic acid solution, dissolve 26 g of polyethylene glycol (surfactant) in 1.5 kg of water to form an aqueous solution of polyethylene glycol; then mix the two to obtain an aqueous solution d, and spray it on the surface of the base layer formed by spray seeding the spray seeding matrix material c; The organic polymer material reacts with a foaming agent, a cross-linking agent, a toughening agent, a pH regulator, and a surfactant to form sponge soil with a "sponge-like" three-dimensional network porous structure. Sodium carbonate reacts with dilute acetic acid solution to produce gas, forming a foaming structure. At the same time, magnesium ions in magnesium chloride react with sodium alginate to form a cross-linked structure, generating a sponge-like porous structure.

[0035] The toughening agent can help improve the plasticity and flexibility of the material during the material forming process, reduce problems such as cracks and breakages during forming, and improve the quality and performance of the sponge soil formed products.

[0036] The sponge soil prepared according to this embodiment has a good "sponge-like" three-dimensional network porous structure system, with high water absorption, water retention, and air permeability, effectively improving the water retention rate and water absorption rate (conserving water sources). As Figure 1 shown is the initial state of the sponge soil of this embodiment, Figure 2 shown is the natural air-dried state, showing an obvious porous structure.

[0037] The use of the toughening agent can enhance the adhesion and improve the performance of preventing rainwater erosion.

[0038] Example 8 Raw material composition (mass percentage) of the sponge soil forming agent: Sodium alginate: 400 g, as the main film-forming and water-retaining component, can effectively improve the soil structure; Polyacrylamide: 250 g, enhancing the viscosity of the forming agent and promoting the aggregation of soil particles; Sodium bicarbonate: 120 g, used to adjust the soil pH and help the forming agent disperse better in the soil; Ferric chloride: 80 g, as a cross-linking agent, supplementing iron elements to the soil and participating in the interaction between soil particles; Magnesium chloride: 10 g, as a cross-linking agent, causing cross-linking reactions between components and stabilizing the structure of the forming agent Toughening agent: 4 g; Surfactant: 1 g, to improve the hydrophilicity of the forming agent; Plant fiber, 20 g.

[0039] Method for uniformly mixing the above sponge soil forming agent with 30 kg of soil matrix to prepare sponge soil (water: 20 kg, as a solvent to dissolve and mix other raw materials): Step S1, first, according to the weight ratio, take the foaming agent, cross-linking agent, toughening agent, and soil, add water to dissolve, and stir well to form a uniform aqueous dispersion a; the prepared sponge soil forming agent.

[0040] Step S2: Mix the organic polymer material in corresponding weight proportions with water to obtain the basic reaction material b. Step S3: Mix the aqueous dispersion a prepared in Step S1 with the basic reaction material b prepared in Step S2 to obtain the basic spraying substrate material c. Step S4: Dissolve the pH regulator and surfactant material in corresponding weight proportions in water to prepare the spraying aqueous solution d, and spray the prepared aqueous solution d onto the surface of the base layer formed by spraying the spraying substrate material c. The organic polymer material reacts with the foaming agent, crosslinking agent, toughening agent, as well as the pH regulator and surfactant to generate a sponge soil with a "sponge-like" three-dimensional network porous structure.

[0041] Figure 3 Shown is the wet external shape of the sponge soil prepared in the laboratory. Figure 4 The effect after dry forming is shown. It can be seen that there is an obvious porous structure. After a period of use and observation, it is found that the water and fertilizer retention capacity of the soil after adding this forming agent is significantly improved, the soil aggregate structure is optimized, the air permeability and water permeability are also improved, which is more conducive to the growth and nutrient absorption of plant roots, and at the same time enhances the resistance of the soil to harsh environments such as drought and flood.

[0042] Example 9 A preparation procedure for sponge soil without soil: First step: Mix 350 g of sodium polyacrylate, 350 g of calcium carbonate with 30 kg of soil evenly, then add 30 kg of water, and stir and mix evenly again. After sodium polyacrylate dissolves, it can effectively increase the soil viscosity, play an anti-scouring effect, and can react with the subsequent added crosslinking agent to form a crosslinked structure.

[0043] Second step: Add the dilute acid (a mixed solution of 185 g of hydrochloric acid and 3 kg of water) mixed with water and 280 g of calcium chloride. After adding, there is no need to stir the system again. Let the above reactants stand for reaction and then proceed to the subsequent steps. During this process, calcium carbonate reacts with the dilute acid to generate bubbles, which can make the soil form a foaming structure. Another product calcium chloride and the calcium chloride added in this process can also make the component sodium polyacrylate generate a crosslinked structure.

[0044] Third step: Dissolve 18 g of sodium dodecyl sulfonate, an auxiliary additive, in 1 kg of water, and add this solution to the above system to improve the hydrophilicity of the soil.

[0045] The effect diagram of the sponge soil prepared in this example is as shown in Figure 5 、 Figure 6 Shown, and it can be seen that there is an obvious porous structure.

[0046] As shown in Figure 7(a), the water absorption test of the sponge soil shows that the water absorption rate is 200% and can be achieved within 10 seconds; Figure 7(b) shows the water retention test of the sponge soil at room temperature in summer, which can be maintained for about one week.

[0047] Figure 8 Figure 4 shows the plant seeds planted in the sponge soil prepared in Examples 7-9, and the plants grow well in it.

[0048] It can be seen that the sponge soil forming agent and the sponge soil of the present invention, through a series of complex reactions occurring between a variety of carefully formulated materials, significantly enhance the colloidal texture of the soil. The sponge soil prepared based on this technology not only has excellent water absorption performance, can efficiently absorb and store a large amount of water, and has high water absorption, water retention, air permeability, and rain erosion prevention performance. More importantly, the enhancement of its colloidal texture enables it to form a strong and effective protective structure after water absorption, effectively resisting the erosion of slope soil by water scouring. This unique advantage makes the sponge soil forming technology stand out in slope ecological restoration. It can not only effectively ensure the stability of the slope soil body, provide a solid foundation for the growth of vegetation, but also promote the effective retention and utilization of nutrients, reduce the loss of nutrients with water, thus more durably supply nutrients to crops, conserve water sources, improve fertilizer utilization efficiency, and can promote the comprehensive restoration and improvement of the slope ecological environment, with broad application prospects.

Claims

1. A sponge soil forming agent, characterized in that: Composed of materials with the following components by weight parts: Organic polymer material: 20 - 50 parts; Foaming agent: 20 - 40 parts; Crosslinking agent: 10 - 30 parts; Toughening agent: 1 - 40 parts, and the toughening agent uses aqueous latex; pH regulator: 10 - 30 parts; Surfactant: 0.5 - 2 parts.

2. The sponge soil forming agent according to claim 1, characterized in that It also includes: Plant fiber: 1 - 40 parts.

3. The sponge soil forming agent according to claim 1 or 2, characterized in that: The organic polymer material serves as the basic reaction material and uses one of sodium polyacrylate, sodium polyvinyl sulfonate, sodium polystyrene sulfonate, sodium alginate or anionic polyacrylamide, or a mixture of any two or three of them.

4. The sponge soil forming agent according to claim 3, characterized in that: The foaming agent adopts one or more of calcium carbonate, barium carbonate, sodium carbonate or sodium bicarbonate.

5. The sponge soil forming agent according to claim 3, characterized in that: The crosslinking agent uses one or more of calcium chloride, magnesium chloride, zinc chloride, barium chloride or ferric chloride.

6. The sponge soil forming agent according to claim 3, characterized in that: The pH regulator uses one or more of dilute hydrochloric acid solution, dilute acetic acid solution or dilute phosphoric acid solution.

7. The sponge soil forming agent according to claim 3, characterized in that: The surfactant adopts a small - molecule surfactant alkyl sulfonate or alkyl benzene sulfonate, or a macromolecule surfactant.

8. A sponge soil uses the sponge soil forming agent as described in any one of claims 1 - 7, and adds 20 - 500 times the weight parts of soil or soil matrix material of the sponge soil forming agent.

9. The sponge soil preparation method according to claim 8, wherein Including the following steps: Step S1: First, take the foaming agent, crosslinking agent, toughening agent and soil according to the weight ratio, add water to dissolve them, and stir well to form a uniform aqueous dispersion a; Step S2: Mix the organic polymer material with the corresponding weight ratio with water and stir well to obtain the basic reaction material b; Step S3: Mix the aqueous dispersion a prepared in Step S1 with the basic reaction material b prepared in Step S2 and stir well to obtain the basic spraying matrix material c; Step S4: Dissolve the pH regulator and surfactant material with the corresponding weight ratio in water to prepare a spraying aqueous solution d, and spray the prepared aqueous solution d onto the surface of the base layer formed by spraying the spraying matrix material c onto the slope surface; The organic polymer material reacts with the foaming agent, crosslinking agent, toughening agent, pH regulator and surfactant to generate a sponge soil with a "sponge - like" three - dimensional network porous structure.

10. The sponge soil preparation method according to claim 9, characterized in that: In Step S1, add the plant fiber with the corresponding weight ratio according to needs and stir well to increase the soil viscosity.

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