Ecological restoration structure and method for side slope

Abstract

The invention relates to the technical field of side slope ecological restoration, and provides a side slope ecological restoration structure and method.The side slope ecological restoration structure comprises a base layer covering the surface of a side slope; the surface layer covers the surface of the base layer; wherein the base layer at least comprises planting soil, turfy soil, organic fertilizer, water, a water-retaining agent, cement and a foaming agent; the surface layer at least comprises seeds and a compound fertilizer. The foaming agent is introduced into the base layer to have a synergistic effect with cement, uniformly distributed microbubbles are generated in situ in the curing process, the porosity of the base layer is remarkably improved, and the volume weight is reduced; compared with a traditional vegetation concrete technology, the base layer has mechanical stability, high porosity and high air permeability and water permeability, a porous environment is created for rooting growth of vegetation, the ecological restoration quality is remarkably improved, and the long-term survival rate of the vegetation is remarkably increased.

Description

Technical Field

[0001] This invention relates to the field of slope ecological restoration technology, and in particular to a slope ecological restoration structure and method. Background Technology

[0002] In engineering projects such as transportation, water conservancy, mining, and urban construction, a large number of natural slopes are excavated or filled, forming artificial exposed slopes. These slopes typically have loose soil structure, poor nutrient content, poor water retention capacity, and lack vegetation cover. They are extremely susceptible to soil erosion, surface peeling, and even geological disasters such as landslides and collapses under the influence of rainfall, wind erosion, or gravity. This not only threatens the safety of engineering projects and the surrounding ecological environment but may also cause serious economic losses and ecological degradation.

[0003] Traditional slope protection methods often employ hard engineering measures such as concrete facing, masonry, and lattice beams. While these methods can provide a certain degree of mechanical stability in the short term, they have significant drawbacks: firstly, they completely block the exchange of matter and energy between the soil and the atmosphere and organisms, disrupting the continuity of the regional ecosystem; secondly, they lack self-repair capabilities, and once cracks or local damage occur, they are prone to accelerated deterioration.

[0004] Against this backdrop, slope ecological restoration technology has emerged. This technology combines engineering protection with ecological restoration by constructing a restoration layer with vegetation growth capabilities, thereby ensuring slope stability while rebuilding vegetation communities and restoring soil fertility and biodiversity.

[0005] The main ecological restoration techniques for slopes include the following: (1) Netting and topsoil spraying: The slope surface is reinforced by traditional slope construction methods such as anchor rods, anchor nails, and netting, and a vegetation layer is constructed by topsoil spraying. However, the vegetation layer constructed by this method is at risk of being washed away, falling off, or collapsing when exposed to water; (2) Ecological bag ecological restoration technology: Ecological bags are filled with soil and connected to the slope through a pre-set anchoring system. Finally, the surface of the bag is greened by means of spraying and seeding. However, this method has a long construction period, high cost per unit area, and poor surface greening effect.

[0006] (3) Vegetation Concrete Ecological Restoration Technology: By adding cement to the mixture of traditional topsoil spraying, the sprayed layer develops a certain strength in the later stages. This gives the sprayed layer a certain resistance to erosion and deformation, eliminating the risk of local (overall) damage to the structure of the sprayed layer. However, spraying using a combination of planting soil and cement results in a continuously graded sprayed material with low natural porosity. Because cement is added to the sprayed layer, it develops a certain strength in the later stages, making it more difficult for vegetation roots to penetrate the vegetation layer, leading to difficulties in later vegetation growth. With this spraying technology, the root system of vegetation is relatively shallow. The risk of water loss and death is higher in winter and during the dry season.

[0007] Therefore, there is an urgent need to design a slope ecological restoration technology with strong erosion resistance of the vegetation layer, high vegetation survival rate, and good greening effect. Summary of the Invention

[0008] This invention provides a slope ecological restoration structure and method to solve the technical problems of existing slope ecological restoration technologies, such as poor erosion resistance of the vegetation layer, low vegetation survival rate, and low greening effect.

[0009] This invention provides a slope ecological restoration structure, comprising: The base layer, covering the surface of the slope; Top layer, covering the surface of the base layer; The base layer includes at least: planting soil, peat moss, organic fertilizer, water, water-retaining agent, cement, and foaming agent; The surface layer includes at least: seeds and compound fertilizer.

[0010] According to the present invention, a slope ecological restoration structure is provided. The base layer shall contain at least the following per cubic meter: 800-1100 kg of planting soil, 30-60 kg of peat moss, 30-50 kg of organic fertilizer, 350-450 kg of water, 0.1 kg of water-retaining agent, 60-80 kg of cement, and 0.3-0.5 kg of foaming agent. The surface layer contains at least 0.03-0.04 kg of seeds and 0.005-0.01 kg of compound fertilizer per square meter.

[0011] According to the present invention, a slope ecological restoration structure is provided. The base layer also includes 40-60 kg of first fiber per cubic meter; The surface layer also includes 0.5 to 1 kilogram of second fiber per square meter.

[0012] According to the present invention, a slope ecological restoration structure is provided. The base layer also includes 60-80 kg of acid-base balancer per cubic meter.

[0013] This invention also provides a slope ecological restoration method, applied to the above-mentioned slope ecological restoration structure, comprising the following steps: Clean the slope; For slopes with concentrated water catchment, interception and drainage treatment should be carried out; Install reinforced anchoring layers; The base layer material is mixed and sprayed. The surface layer material is mixed and sprayed. The repaired structure after spraying is then maintained.

[0014] According to the slope ecological restoration method provided by the present invention, the step of arranging the reinforced anchoring layer specifically includes: The main edge anchors, overlapping area anchors, auxiliary edge anchors, auxiliary overlapping area anchors, and internal anchors are laid out in sequence. Lay high-strength steel wire mesh along the slope from top to bottom; The high-strength steel wire mesh is securely tied to the anchor nails and adjacent mesh panels.

[0015] According to a slope ecological restoration method provided by the present invention, before the step of mixing the base material and spraying, the method further includes: The planting soil is screened by particle size, and the planting soil with a particle size less than or equal to the particle size threshold is removed.

[0016] According to the slope ecological restoration method provided by the present invention, the step of mixing the base material and spraying it specifically includes: Add the planting soil, peat moss, first fiber, organic fertilizer, cement, acid-base adjuster, foaming agent and water into the concrete mixer in the following order and mix for the preset time. The prepared base layer material is sprayed using an air compressor.

[0017] According to the slope ecological restoration method provided by the present invention, the step of maintaining the restored structure after hydroseeding specifically includes: The surface layer is covered with non-woven fabric for curing. Install irrigation pipe networks and / or use pipe-driven sprinkler systems for water spraying and maintenance, with highly atomized water output.

[0018] According to the slope ecological restoration method provided by the present invention, after the step of maintaining the restored structure after hydroseeding, the method further includes: The target parameters are tested, and if the test fails, the material ratio of the base layer is adjusted in a timely manner.

[0019] The above-mentioned one or more technical solutions provided by the present invention have at least the following beneficial technical effects: Introducing a foaming agent into the base layer works synergistically with cement to generate uniformly distributed microbubbles in situ during the curing process, significantly improving the porosity of the base layer and reducing its bulk density; simultaneously, the cement provides the necessary bonding strength, effectively resisting the erosion of the vegetation layer by concentrated rainfall / water runoff, ensuring a long-term stable growth environment for vegetation, achieving coordinated deformation with the slope, and preventing voids and delamination between the vegetation layer and the slope; compared with traditional vegetation concrete technology, the base layer of the present invention combines mechanical stability with high porosity, possessing high air and water permeability, creating a porous environment for vegetation rooting and growth, significantly improving the quality of ecological restoration and the long-term survival rate of vegetation. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the plant root environment in the repair structure provided in the embodiment of the present invention; Figure 2 This is one of the schematic diagrams before the construction of the slope repaired using an embodiment of the present invention; Figure 3 This is the second schematic diagram of the slope repaired using the embodiments of the present invention before construction; Figure 4 This is one of the schematic diagrams illustrating the repair process using the repair method provided in the embodiments of the present invention; Figure 5 This is the second schematic diagram of the repair process using the repair method provided in the embodiments of the present invention; Figure 6 This is the third schematic diagram of the repair process using the repair method provided in the embodiments of the present invention; Figure 7 This is the fourth schematic diagram of the repair process using the repair method provided in the embodiments of the present invention; Figure 8 This is one of the schematic diagrams of a slope repaired using the repair method provided in the embodiments of the present invention; Figure 9 This is the second schematic diagram of a slope repaired using the repair method provided in this embodiment of the invention; Figure 10 This is a schematic diagram illustrating the detection method, index requirements, and detection frequency of the target parameter provided in the embodiments of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0023] The following is combined Figures 1-10 This invention describes the slope ecological restoration structure and method according to embodiments of the present invention.

[0024] This invention provides a slope ecological restoration structure, characterized by comprising: a base layer, covering the surface of the slope; and a surface layer, covering the surface of the base layer; wherein, each cubic meter of the base layer comprises at least: 800-1100 kg of planting soil, 30-60 kg of peat moss, 30-50 kg of organic fertilizer, 350-450 kg of water, 0.1 kg of water-retaining agent, 60-80 kg of cement, and 0.3-0.5 kg of foaming agent; and each square meter of the surface layer comprises at least: 0.03-0.04 kg of seeds and 0.005-0.01 kg of compound fertilizer.

[0025] Specifically, such as Figure 1 As shown, the embodiments provided by this invention introduce a foaming agent and cement to work synergistically in the base layer, generating uniformly distributed microbubbles in situ during the curing process, significantly increasing the porosity of the base layer and reducing its bulk density. Simultaneously, the cement provides the necessary bonding strength, effectively resisting the erosion of the vegetation layer by concentrated rainfall / water runoff, ensuring a long-term stable growth environment for vegetation, achieving coordinated deformation with the slope, and preventing voids and delamination between the vegetation layer and the slope. Compared with traditional vegetation concrete technology, the base layer of this invention combines mechanical stability with high porosity, exhibiting high air and water permeability, creating a porous environment for vegetation rooting and growth, significantly improving the quality of ecological restoration and the long-term survival rate of vegetation.

[0026] It should be understood that the components contained in each cubic meter of the base layer refer to the mass of each component contained in the wet volume of the base layer material before it is cured or in the standard compacted state when the total volume is 1 cubic meter; the components contained in each square meter of the surface layer refer to the mass of the components contained in the surface layer when the projected area formed on the slope surface after construction is 1 square meter.

[0027] In some possible implementations, the planting soil is preferably loam or sandy loam. Peat moss is a moderately decomposed, low-grade peat with high porosity, strong cation exchange capacity, and good water retention, effectively improving the granular structure and buffering performance of the base layer and promoting microbial activity. Organic fertilizer is well-rotted livestock and poultry manure, compost, or commercial organic fertilizer, providing slow-release nutrients to support the medium- to long-term growth needs of plants. The water-retaining agent is cross-linked sodium polyacrylate or starch-grafted copolymer, forming a water "storage-release" regulatory network in the base layer to alleviate drought. Cement is ordinary silicate cement, serving as an inorganic cementing material that, after hydration, imparts the necessary erosion resistance to the base layer, preventing material loss due to rainwater erosion. The foaming agent is a plant-based foaming agent, preferably a composite foam-stabilizing system derived from natural plant extracts (such as saponins, tea saponins, rosin soap, or a combination of one or more plant-derived amino acid derivatives), whose aqueous solution, after mechanical shearing, can generate abundant, uniform, and highly stable micron-sized bubbles. Plant-based foaming agents possess excellent biodegradability, low toxicity, and environmental compatibility. Seeds are pioneer herbaceous or shrub seeds adapted to local climate and soil conditions, such as Bermuda grass, tall fescue, Amorpha fruticosa, and Lespedeza, and can be used alone or in combination according to ecological functions. The compound fertilizer is a fast-dissolving granular compound fertilizer, pulverized and passed through a 60-mesh sieve before use, providing readily available nitrogen, phosphorus, and potassium nutrients for seed germination and early seedling growth.

[0028] It should be noted that, as Figures 1-3 As shown, the slope ecological restoration structure provided in this invention is particularly suitable for ecological protection and vegetation reconstruction of high-altitude and steep slopes. "High-altitude and steep slopes" refers to slopes in high-altitude or high-latitude regions with an average annual temperature below 5°C, an average temperature below -10°C in the coldest month, and significant seasonal freeze-thaw cycles. "Stiff slopes" refers to rock or soil-like slopes with a slope greater than 60°, or even close to vertical. Under these harsh conditions, traditional ecological restoration technologies often face the following challenges: low temperatures inhibit seed germination and root growth; repeated freeze-thaw cycles cause cracking and peeling of the sprayed layer; material adhesion is difficult on steep slopes, leading to slippage or erosion; and poor soil with low water and fertilizer retention capacity makes long-term vegetation survival difficult. To address these problems, the porous lightweight base layer structure in this invention can effectively alleviate frost heave damage. Specifically, plant-based foaming agents are introduced into the base layer to work synergistically with cement, forming a large number of uniformly distributed micron-level interconnected pores. This porous structure not only reduces the material density and alleviates the load pressure on steep slopes, but more importantly, it provides a buffer space for moisture migration, significantly weakening the internal stress generated by ice crystal expansion during freeze-thaw cycles, thereby effectively inhibiting base layer cracking and interlayer delamination.

[0029] In the slope ecological restoration method provided in this invention embodiment, to ensure that the base layer possesses both mechanical stability and ecological habitatability, the amount of foaming agent added needs to be precisely controlled. Systematic experiments have verified that the amount of foaming agent has a decisive influence on the pore structure of the base layer. The following, combined with experimental data, illustrates its reasonable dosage range.

[0030] Multiple sets of specimens were prepared by selecting base materials with the same mix ratio and varying only the amount of foaming agent added. After curing for 7 days, the total porosity was determined using the ring cutter method. Simultaneously, the unconfined compressive strength and vegetation germination rate were tested (using tall fescue as the indicator species, with a seeding rate of 0.035 kg / m²). 2 ).

[0031] The experimental results are shown in the table below:

[0032] Experiments show that: When the amount of foaming agent added is less than 0.30 kg / m³ 3 At that time, insufficient bubble generation and a base layer porosity of less than 35% resulted in high strength but poor air and water permeability, inhibiting seed germination and root growth. When the foaming agent addition amount is higher than 0.50 kg / m³ 3 At that time, although the porosity continued to increase, the base structure tended to be loose, and the strength rapidly decreased to below 0.31 MPa. Under simulated rainfall conditions, surface particle loss and local peeling occurred, and the ecological function declined instead.

[0033] When the amount of foaming agent added is controlled at 0.30-0.5 kg / m³ 3 Within the specified range, the porosity of the base layer is stable at 35%–40%, with pore sizes mainly ranging from 50 to 300 μm and good connectivity. The unconfined compressive strength after 7 days remains at 0.37–0.52 MPa, which not only meets the engineering requirements for erosion resistance but also provides sufficient space for plant roots to grow, significantly improving the vegetation germination rate.

[0034] Therefore, in the preferred embodiment of the present invention, the amount of foaming agent added should be strictly controlled at 0.3 to 0.5 kg per cubic meter of base layer. This range is a technical balance point determined based on a large number of field tests and indoor simulation verifications. It avoids the problem of "strong but not penetrating" due to insufficient dosage, and also prevents the risk of "sparse and easily collapsed" caused by excessive dosage, thereby achieving synergistic optimization of the "mechanical-ecological" performance of the slope repair structure.

[0035] According to an embodiment of the present invention, a slope ecological restoration structure includes, per cubic meter of base layer, 40-60 kg of first fiber; and per square meter of surface layer, 0.5-1 kg of second fiber.

[0036] It should be understood that the base and surface layers of the slope ecological restoration structure further include fiber-reinforced components to improve the material's crack resistance, erosion resistance, and construction adhesion performance.

[0037] In some possible implementations, the first fiber is a woody fiber or plant straw fiber with a length of 6–19 mm, preferably a natural cellulose fiber modified by alkali treatment or thermal milling. This fiber possesses good hydrophilicity, dispersibility, and interfacial bonding ability with cement. During the mixing of the base course mixture, the first fiber is evenly distributed in the matrix, forming a three-dimensional network reinforcement structure, effectively inhibiting the formation of plastic shrinkage cracks and significantly improving the tensile strength and rainwater erosion resistance of the sprayed layer. Simultaneously, this fiber is biodegradable in the natural environment, causing no secondary pollution, and its degradation process can further improve the soil pore structure and promote root expansion.

[0038] In some possible implementations, the second fiber is a short-cut wood fiber, coconut fiber, or pulp fiber with a length of 3–12 mm. The second fiber mainly plays the following roles in the surface layer: as a seed carrier, it distributes the seeds evenly and firmly attaches them to the base surface through physical entanglement and adsorption, preventing seed loss due to wind erosion or initial rainfall; it forms a microscale covering layer, reducing moisture evaporation and maintaining the moist microenvironment required for seed germination; and it provides temporary shading and buffering during the seedling emergence stage.

[0039] According to an embodiment of the present invention, a slope ecological restoration structure further includes 60-80 kg of acid-base neutralizing agent per cubic meter of the base layer.

[0040] It should be understood that acid-base balancers are used to adjust and stabilize the pH value of the base mixture, keeping it in a slightly acidic to neutral range suitable for plant growth, thereby overcoming the problem of local alkalization caused by cement hydration products and avoiding the inhibition of seed germination, root development and soil microbial activity by a high pH environment.

[0041] In some possible implementations, the acid-base balancer is selected from natural weakly acidic mineral materials or slow-release acidic conditioners, preferably including but not limited to: weathered coal, lignite, humic acid powder, diatomaceous earth-supported citric acid complex, or one or more combinations of activated acidic volcanic rock powder. Weathered coal or lignite, being rich in humic acid, fulvic acid, and organic carboxyl functional groups, not only possesses excellent buffering and acid-regulating capabilities but also simultaneously provides organic matter and trace elements, thus serving as a soil amendment. The diatomaceous earth-supported citric acid complex, through its porous carrier, enables the slow release of acidic components, avoiding the adverse effects of a sudden pH drop on early cement hydration. Furthermore, the acid-base balancer also has auxiliary water retention and ion exchange functions, enhancing the adsorption and slow release capacity of nutrients such as potassium, calcium, and magnesium in the soil layer, further improving the rhizosphere microenvironment.

[0042] like Figures 4-9 As shown, this embodiment of the invention also provides a slope ecological restoration method, applied to the above-mentioned slope ecological restoration structure, comprising the following steps: S1, Clear the slope; S2, interception and drainage treatment for slopes with concentrated water collection; S3, Install reinforced anchoring layer; S4, mix the base material and spray it; S5, mix the surface layer material and spray it; S6, perform maintenance treatment on the repaired structure after spraying.

[0043] It should be understood that the above-mentioned restoration method, through systematic pretreatment, structural construction, and post-construction maintenance, ensures a firm bond between the restoration layer and the original slope surface, stable function, and efficient vegetation establishment. Through this systematic construction process, the present invention not only ensures precise proportioning of restoration materials and efficient construction, but also significantly improves the overall adhesion, erosion resistance, and vegetation establishment success rate of the slope ecological restoration structure through the synergistic effect of pretreatment, anchoring, layered spraying, and scientific maintenance. It is applicable to various complex slope scenarios in transportation, mining, water conservancy, and municipal engineering projects.

[0044] In some possible implementations, when intercepting and draining water from slopes with concentrated catchments, it is necessary to survey the hydrological conditions at the top, surface, and toe of the slope to identify surface runoff paths and potential catchment areas. Interception ditches are constructed at the top of the slope, and drainage channels or guide ribs are laid longitudinally along the slope. If necessary, blind drainage ditches or collection wells are installed at the toe. Drainage structures can be constructed using masonry, permeable concrete, or geosynthetic drainage materials. The purpose is to prevent rainwater from locally accumulating and eroding the repair layer on the slope, ensuring the stability of the base and surface layers during the initial setting and vegetation germination stages.

[0045] In some possible implementations, slope clearing involves the following steps: First, a comprehensive survey of the slope surface is conducted to identify and remove all unstable or potentially loose material, including but not limited to weathered debris, loose soil, detached rock fragments, plant root remnants, artificial waste, and other non-structural attachments. Clearing can be carried out manually in conjunction with small machinery. The clearing depth should be sufficient to expose stable parent rock or dense, undisturbed soil layers, ensuring the slope surface has sufficient bearing capacity and a cohesive base. For areas with significant protrusions (such as boulders, hard rock nodules, or construction-related protrusions), if their tops protrude ≥5cm above the surrounding slope surface, they should be chiseled or trimmed to avoid creating spraying dead zones, stress concentration areas, or water flow deflection points, which could affect the uniform coverage of the base layer and the overall structural integrity. The trimmed slope contour should have a smooth transition, without sharp edges or abrupt steps. It should be noted that the above-mentioned refined slope treatment process not only effectively eliminates physical obstacles that affect the adhesion of the repair layer, but also significantly improves the interface bonding strength between the base layer and the original slope, providing a reliable foundation for subsequent anchoring, hydroseeding and vegetation establishment. It is especially suitable for slope engineering scenarios with high and steep slopes, broken slopes or complex rock-soil interfaces.

[0046] According to an embodiment of the present invention, a slope ecological restoration method includes the following steps for setting up a reinforced anchoring layer: S31, the edge main anchors, the overlapping area anchors, the edge auxiliary anchors, the overlapping area auxiliary anchors, and the internal anchors are laid out in sequence; S32, high-strength steel wire mesh is laid along the slope from top to bottom; S33, the high-strength steel wire mesh is firmly tied to the anchor nails and adjacent mesh panels.

[0047] In some possible implementations, the anchor should be perpendicular to the local slope surface where it is located (preferably with the anchor hook parallel and close to the slope surface). Only when the local slope angle is greater than 75° and the anchor is installed by drilling and grouting, the angle between the anchor and the horizontal plane should not be less than 15° and should be downwards towards the slope. High-strength steel wire mesh should be made of machine-woven flexible iron wire with a wire diameter of not less than 2.0mm and a mesh diameter between 5cm and 8cm. The high-strength steel wire mesh should be laid from top to bottom, with an overlap width of 10cm to 20cm between adjacent mesh panels. The high-strength steel wire mesh panels should be securely tied to the anchors and to each other. The distance between the mesh panels and the slope surface should be 2 / 3 of the vegetation layer thickness.

[0048] It should be understood that the above-mentioned refined and graded anchoring system not only significantly improves the adhesion safety of the sprayed base layer on steep slopes, but also effectively disperses the gravity component and hydrodynamic load through the synergistic effect of edge reinforcement, overlapping reinforcement and internal uniform anchoring, avoiding early failure caused by local stress concentration, and providing reliable structural support for the successful construction of the subsequent ecological functional layer.

[0049] According to an embodiment of the present invention, a slope ecological restoration method further includes, before the steps of mixing the base material and spraying, screening the planting soil by particle size and removing planting soil with a particle size less than or equal to a particle size threshold.

[0050] It should be understood that in the slope ecological restoration method of this invention, particle size screening of the planting soil is a key pretreatment step to optimize the workability, pore structure, and vegetation adaptability of the base mixture. The particle size threshold can be 2.36 mm, meaning that fine particles with a particle size less than or equal to 2.36 mm are screened out. This threshold is not based on a theoretically ideal gradation, but rather is an engineering optimization parameter determined after comprehensively considering on-site equipment conditions, ease of operation, material availability, and the final structural performance.

[0051] Specifically, in actual slope restoration projects, planting soil is usually sourced locally or purchased nearby, and its natural gradation often contains a large amount of silt, clay, and fine sand. If unscreened soil is used directly, although a continuous gradation can be formed, the excessively high content of fine particles will lead to a significant increase in the specific surface area of ​​the mixture, increasing water demand, which in turn affects the fluidity of the spraying. Furthermore, after cement hydration, a dense matrix is ​​formed, which is not conducive to the foaming agent building interconnected pores, ultimately inhibiting the penetration of plant roots.

[0052] However, while further lowering the particle size threshold can more thoroughly remove fine particles, it is difficult to achieve efficiently under on-site construction conditions. This is because current slope ecological restoration projects commonly use mobile vibrating screens for on-site screening, and these screens often use woven wire mesh (non-standard test sieves). When the designed sieve aperture size is less than 1.18mm, the effective sieve diameter is significantly reduced due to the wire obstruction, easily causing screen clogging, a sharp decline in screening efficiency, and frequent cleaning that severely impacts construction progress. Furthermore, excessively fine screens are prone to deformation or damage under high dust and high humidity conditions, resulting in high maintenance costs and poor operability. Conversely, if the particle size threshold is increased to 4.75mm, too much fine sand and powder are retained, failing to effectively improve substrate density and making it difficult to form a porous structure conducive to root growth. Simultaneously, the increased proportion of large-diameter gravel may exacerbate wear on hydroseeding equipment, cause slurry segregation, or result in excessively rough surfaces, affecting surface layer adhesion.

[0053] Therefore, after extensive field testing and process verification, 2.36mm has been tentatively determined as the optimal particle size threshold that balances technical effectiveness and construction feasibility. This size corresponds to the upper limit of medium sand in the standard sieve series and matches the minimum reliable sieve aperture size of commonly used wire woven vibrating sieves—with a wire diameter of approximately 1.0mm, the 2.36mm square hole sieve can be stably manufactured, is not prone to clogging, has high screening efficiency, and is suitable for continuous field operations.

[0054] It should be understood that the discontinuous gradation formed after sieving out fine particles ≤2.36mm does not weaken the mechanical stability of the base course. On the contrary, this invention compensates for this by actively introducing functional fillers and cementing components: cement, as an inorganic cementing material, generates products such as calcium silicate hydrate after hydration, effectively cementing the coarse particle skeleton; the first fiber forms a three-dimensional network in the matrix, bridging the gaps between particles and inhibiting the propagation of microcracks; the microbubbles generated by the foaming agent form uniformly distributed micropores after curing, which not only reduces the bulk density but also provides additional internal friction through the pore wall structure. The synergistic effect of the above components enables the discontinuous gradation base course to not only have sufficient erosion resistance but also form a high interconnected porosity and good root penetration channels, achieving an organic unity of "structural stability" and "ecologically habitable environment".

[0055] According to an embodiment of the present invention, a slope ecological restoration method includes the steps of mixing the base material and spraying it, specifically comprising: S41, add the planting soil, peat soil, first fiber, organic fertilizer, cement, acid-base adjuster, foaming agent and water into the concrete mixer in sequence and mix for the preset time. S42, using an air compressor to spray the mixed base material.

[0056] In some possible implementations, a forced twin-shaft concrete mixer can be used to perform dry and wet mixing according to a strict feeding sequence to ensure uniform dispersion of each component and avoid clumping or performance degradation. The feeding sequence and key operating points are as follows: First, the dry material premixing stage: First, the screened planting soil, peat moss, and first fiber are added to a mixer and dry-mixed for 2-3 minutes. This stage aims to initially disperse the lightweight fiber in the heavy soil particles, preventing the fiber from flocculating after water is added later.

[0057] Second, the addition of functional dry ingredients: Add organic fertilizer, cement, and acid-base adjuster in sequence, and continue to dry mix for 1-2 minutes to ensure that the cementitious material and conditioner are evenly coated on the surface of the soil particles, avoiding local alkalization or uneven reaction.

[0058] Third, pre-dilution and introduction of the foaming agent: Plant-based foaming agents need to be mixed with 20% to 30% of the total mixing water before being added, and then prepared into a stable foam slurry by high-speed stirring or a special foaming device. This foam slurry is then introduced into the stirring system as one of the liquid phase components.

[0059] Fourth, the wet mixing stage: While continuously stirring, slowly add the remaining mixing water, controlling the wet mixing time to 3-5 minutes, until a slurry with uniform color, no dry powder, no fiber clumps, and moderate fluidity is formed. The slump of the mixture should be controlled at 80-120 mm to meet the requirements of pumping and spraying.

[0060] It should be noted that the above-mentioned material feeding sequence design has a clear technical purpose: first, dry-mixing lightweight fibers with coarse-grained soil can effectively suppress fiber floating; then, adding cement and conditioning agent can prevent them from contacting water too early and causing local hydration or pH changes; the foaming agent is introduced in the form of pre-foaming, which can retain the integrity of the air bubbles to the maximum extent and ensure the development of the pore structure of the final base layer.

[0061] In some possible implementations, hydroseeding employs a dry or wet concrete spraying machine with a screw pump system, powered by an air compressor. During hydroseeding, the operator starts from the bottom of the slope and moves back and forth horizontally, advancing layer by layer to ensure the material evenly covers the surface of the reinforced anchoring layer. The thickness of a single spraying is controlled at 3–5 cm, with a total design thickness typically of 8–12 cm. If multiple layers are required, the interval between layers should not exceed the initial setting time to ensure interlayer adhesion. The base and surface layers should ideally be sprayed in one continuous process, and the mixture should be completely sprayed within 6 hours. The distance between the spray gun and the slope should be maintained at 0.8–1.5 m, and the spray angle controlled at 70°–90° to reduce rebound loss and improve compaction. During hydroseeding, the flowability of the material should be monitored in real time, and the water volume adjusted slightly if necessary to ensure that the surface of the base layer is free of obvious aggregate segregation, voids, or dry spots after formation.

[0062] The hydroseeding thickness of the vegetation layer is determined based on the slope type and gradient, as shown in the table below:

[0063] According to an embodiment of the present invention, a slope ecological restoration method includes a step of maintaining the restored structure after hydroseeding, specifically comprising: S61, the surface layer is covered with non-woven fabric for curing; S62, laying irrigation pipe network and / or pipe sprinkling for water spraying maintenance, with highly atomized water output.

[0064] It should be understood that non-woven fabric should be laid on the surface of the repaired structure immediately within 0.5 to 2 hours after the surface spraying operation is completed. The non-woven fabric should have properties such as hydrophilicity, breathability, and moisture retention.

[0065] In some possible implementations, during installation, the non-woven fabric should be laid down the slope from top to bottom, with an overlap of at least 10cm between adjacent strips. It should be secured to the slope using U-shaped steel nails or biodegradable plastic nails to prevent it from being blown away by wind or washed away by rain. The main functions of the non-woven fabric covering include: reducing surface moisture evaporation and maintaining the moist microenvironment required for seed germination; buffering the impact of raindrops to prevent the loss of seeds and fine particles; providing moderate shading to reduce the stress on seedlings caused by high summer temperatures or strong ultraviolet radiation; and inhibiting early germination of weeds to reduce competition. Depending on the vegetation emergence and climatic conditions, the non-woven fabric is typically used for 15–30 days. Once the seedlings reach a height of 3–5cm and their root systems are initially anchored, the covering can be gradually removed.

[0066] In some possible implementations, when using an irrigation network, main and branch pipes can be laid at appropriate locations on the slope top or slope surface, with branch pipes arranged along contour lines at intervals of 5-8 meters. Low-pressure atomizing nozzles are installed on the branch pipes to form a fine water mist, preventing water flow from eroding the unconsolidated sprayed layer. When using a mobile pipe-driven watering method, for small or temporary projects, a hose can be connected to a water pump, with a handheld atomizing spray gun attached to the end, allowing manual and even watering along the slope. The spray gun outlet should be equipped with a perforated atomizing disc or a vortex atomizer to ensure highly atomized water, uniform spray coverage, and no localized water accumulation or erosion.

[0067] In addition, the frequency and amount of watering should be dynamically adjusted according to climatic conditions: Initial stage (days 1-7): water 2-4 times daily, each time saturating the top 5cm layer without runoff; Mid-stage (days 8-14): water 1-2 times daily to maintain substrate moisture content; Late stage (after day 15): intermittently water as needed based on rainfall, gradually transitioning to natural cultivation. Specifically, in cold regions or arid, windy environments, the non-woven fabric covering time should be increased and the frequency of misting watering increased to compensate for evaporation losses; while in rainy seasons or rainy areas, manual watering can be suspended, but drainage systems must be ensured to prevent waterlogging that could lead to seed rot due to lack of oxygen.

[0068] According to an embodiment of the present invention, a slope ecological restoration method further includes, after the step of curing the restored structure after hydroseeding, the method further includes: S7, test the target parameters, and if the test fails, adjust the material ratio of the base layer in a timely manner.

[0069] It should be understood that, to ensure the restoration layer possesses both mechanical stability and ecological habitat viability, after the maintenance treatment is completed, a further process including systematic testing and feedback control of key performance indicators is required. Target parameters refer to the core physicochemical and mechanical indicators that directly affect the structural safety of the slope and the effectiveness of vegetation establishment. Specifically, these may include: aeration porosity, pH value, hydrolyzable nitrogen, available phosphorus, available potassium, unconfined compressive strength, and erosion modulus.

[0070] The detection methods and index requirements for each target parameter are as follows: Figure 10 As shown, the acceptable range of the target parameters and the control logic are as follows: First, the aeration porosity should be ≥30% to ensure both water infiltration and gas exchange, while maintaining sufficient water retention capacity. If the aeration porosity is too low, it indicates that the substrate is too dense, and the amount of foaming agent should be increased or the particle size of the planting soil should be rechecked.

[0071] Second, a pH value of 6.0–8.5 is suitable for the growth of most plants. If the pH is >7.5, increase the amount of acid-base balancer (such as humic acid); if the pH is <6.0, reduce the amount or check the degree of acidification of the organic fertilizer.

[0072] Third, hydrolyzable nitrogen should be ≥60mg / kg to ensure nitrogen supply to plants in the early stages. If the hydrolyzable nitrogen concentration is below the standard, the amount of organic fertilizer added or the nitrogen ratio in the surface compound fertilizer can be increased.

[0073] Fourth, available phosphorus ≥ 20 mg / kg. If available phosphorus is low, the P2O5 content can be increased in the surface compound fertilizer, or phosphate rock powder can be added to the base layer.

[0074] Fifth, available potassium ≥ 1.0 * 10 2 mg / kg. If available potassium is insufficient, K2O should be supplemented first through surface compound fertilizer, or organic fertilizer with high potassium content (such as wood ash base fertilizer) should be selected.

[0075] Sixth, the unconfined compressive strength is 0.3–0.45 MPa. If the unconfined compressive strength is <0.3 MPa, the amount of cement can be increased, for example, from 60–80 kg to 70–85 kg, or the water-to-material ratio can be optimized (reducing the mixing water by 5%–10%). If the unconfined compressive strength is too high, it may inhibit root penetration, so the amount of cement should be reduced and the foaming agent should be increased.

[0076] Seventh, erosion modulus ≤ 1.0 * 10 2 g / (m 2 (.h). Among them, the erosion modulus is based on a rainfall intensity of 80 mm / h. If the erosion modulus exceeds the standard, it indicates insufficient erosion resistance. The fiber network should be strengthened, the anchoring density optimized, or the surface roughness of the base layer improved.

[0077] Additionally, it should be noted that the above tests should be conducted 7±1 days after the base layer is sprayed, every 500m. 2 At least one testing unit should be set up. If any target parameter exceeds the acceptable range, it is judged as "inspection unqualified," and large-scale construction must be suspended. The cause must be analyzed, and the base layer mix ratio of subsequent batches should be adjusted according to the above strategy. After adjustment, a test of at least 10m should be conducted. 2 After a trial spraying verification confirms that all target parameters meet the standards, construction can continue.

[0078] By establishing a multi-dimensional testing system centered on aeration porosity, nutrients, strength, and corrosion resistance, this invention significantly improves the scientific nature, reliability, and long-term ecological function of slope ecological restoration projects, and is particularly suitable for ecologically sensitive areas, steep slopes, and high-standard infrastructure projects.

[0079] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A slope ecological restoration structure, characterized in that, include: The base layer, covering the surface of the slope; Top layer, covering the surface of the base layer; The base layer includes at least: planting soil, peat moss, organic fertilizer, water, water-retaining agent, cement, and foaming agent; The surface layer includes at least: seeds and compound fertilizer.

2. The slope ecological restoration structure according to claim 1, characterized in that, The base layer shall contain at least the following per cubic meter: 800-1100 kg of planting soil, 30-60 kg of peat moss, 30-50 kg of organic fertilizer, 350-450 kg of water, 0.1 kg of water-retaining agent, 60-80 kg of cement, and 0.3-0.5 kg of foaming agent. The surface layer contains at least 0.03-0.04 kg of seeds and 0.005-0.01 kg of compound fertilizer per square meter.

3. The slope ecological restoration structure according to claim 2, characterized in that, The base layer also includes 40-60 kg of first fiber per cubic meter; The surface layer also includes 0.5 to 1 kilogram of second fiber per square meter.

4. The slope ecological restoration structure according to claim 2 or 3, characterized in that, The base layer also includes 60-80 kg of acid-base balancer per cubic meter.

5. A method for ecological restoration of slopes, characterized in that, The application of the slope ecological restoration structure according to any one of claims 1-4 includes the following steps: Clean the slope; For slopes with concentrated water catchment, interception and drainage treatment should be carried out; Install reinforced anchoring layers; The base layer material is mixed and sprayed. The surface layer material is mixed and sprayed. The repaired structure after spraying is then maintained.

6. The slope ecological restoration method according to claim 5, characterized in that, The step of laying the reinforced anchoring layer specifically includes: The main edge anchors, overlapping area anchors, auxiliary edge anchors, overlapping area auxiliary anchors, and internal anchors are laid out in sequence. Lay high-strength steel wire mesh along the slope from top to bottom; The high-strength steel wire mesh is securely tied to the anchor nails and adjacent mesh panels.

7. The slope ecological restoration method according to claim 5, characterized in that, Before the step of mixing the base material and spraying it, the method further includes: The planting soil is screened by particle size, and the planting soil with a particle size less than or equal to the particle size threshold is removed.

8. The slope ecological restoration method according to claim 5, characterized in that, The step of mixing the base material and spraying it specifically includes: Add the planting soil, peat moss, first fiber, organic fertilizer, cement, acid-base adjuster, foaming agent and water into the concrete mixer in the following order and mix for the preset time. The prepared base layer material is sprayed using an air compressor.

9. The slope ecological restoration method according to claim 5, characterized in that, The steps for maintaining the repaired structure after hydroseeding specifically include: The surface layer is covered with non-woven fabric for curing. Install irrigation pipe networks and / or use pipe-driven sprinkler systems for water spraying and maintenance, with highly atomized water output.

10. The slope ecological restoration method according to claim 5, characterized in that, After the step of curing the repaired structure after hydroseeding, the method further includes: The target parameters are tested, and if the test fails, the material ratio of the base layer is adjusted in a timely manner.

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