High-pressure air injection hardened soil splitting and filling improvement technology

Abstract

The invention discloses a high-pressure air injection hardened soil splitting and filling improvement technology. Soil water permeability improvement is achieved through minimally invasive physical disturbance. Firstly, vertical holes are drilled in the hardened soil surface, a special spraying device is inserted after water injection, and the holes are sealed; high-pressure air is used for directionally impacting the soil layer from the nozzles, and radial net-shaped cracks and cavity channels extending to the earth surface from the hole bottoms are formed. Then granular materials such as gravels are continuously filled into the cavity, high-pressure air is synchronously and circularly sprayed and matched with ground surface water injection, the materials are fully permeated and filled by means of the instantaneous liquefaction effect, and a three-dimensional water guide network is constructed. After multi-hole-site collaborative operation, the underground water guide channels are communicated with one another to form a global drainage system. According to the technology, through the synergistic effect of air splitting and material filling, the limitation of a traditional ploughing technology is broken through, damage of mechanical operation to earth surface vegetation and root systems is avoided, and no chemical pollution exists in the construction process. The method is particularly suitable for sensitive areas such as ancient tree protection areas, facility agriculture parks and historical gardens, soil structure improvement can be achieved while the earth surface integrity is maintained, the problem of ventilation and water permeation obstacles caused by hardening is solved, and an innovative scheme is provided for eco-friendly soil remediation.

Description

Technical Field

[0001] The present invention relates to the fields of agriculture and municipal gardening. It is a high-pressure air jet compacted soil splitting and filling improvement technology. It mainly targets the soil compaction problem in ecologically sensitive areas such as ancient tree protection areas, facility agricultural parks and historical gardens, and improves soil permeability through physical minimally invasive methods. This technology effectively solves the problem of traditional tillage operations damaging surface vegetation and cultural heritage through non-mechanical intervention means, and is particularly suitable for special scenarios where strict protection of surface integrity is required. Background Art

[0002] Soil compaction is a common problem faced by the fields of agriculture, ecology and landscaping, mainly caused by factors such as organic matter loss, mechanical compaction, and over-irrigation. Compacted soil has a dense structure, poor air permeability, and low permeability, which seriously hinders the growth of plant roots, water infiltration, and nutrient circulation, and even causes secondary problems such as increased surface runoff and soil erosion. Traditional soil improvement mostly relies on mechanical tillage to loosen the soil layer by physical breaking, but such methods cause serious damage to surface vegetation and are difficult to apply to sensitive areas such as ancient tree protection areas, historical gardens, or facility agriculture areas where the integrity of the surface needs to be protected. In addition, chemical improvements (such as adding soil conditioners) have pollution risks, while biological improvements (such as microbial or plant root repair) have long cycles and unstable effects. Therefore, there is an urgent need to develop a micro-disturbance, non-destructive soil improvement technology.

[0003] In the existing technology, although mechanical tillage can quickly improve the surface soil structure, its large-scale operation will destroy the surface vegetation, root network and historical relics, and due to the limited tillage depth, it is difficult to cure the deep compaction problem; chemical amendments may change the physical and chemical properties of the soil, and long-term use may easily cause salinization or heavy metal accumulation; bioremediation technology depends on environmental conditions, has a long cycle and has limited effect on severely compacted soil. In addition, traditional methods generally lack the systematic construction of water and air channels inside the soil, making it difficult to achieve long-term stability of the soil structure. Summary of the invention

[0004] In response to the above problems, the present invention provides an improved technology for splitting and filling compacted soil by high-pressure air jetting, which takes minimally invasive physical disturbance as the core and breaks through the limitations of traditional methods. First, multiple holes (vertical holes) are drilled on the compacted surface through small drilling tools and other processes to minimize physical damage to the surface; then, water is injected into the holes and a special jet device is inserted to use high-pressure air to directionally split the soil layer, forming a radial crack network and cavity channels extending from the bottom of the hole to the surface. This process uses air kinetic energy to achieve deep soil cutting, avoids strong vibrations and surface disturbances caused by mechanical plowing, and significantly reduces damage to the roots of vegetation.

[0005] The core innovation of the technology lies in combining high-pressure splitting with granular filling: by cyclically injecting high-pressure air and supplemented by surface water injection, an instantaneous liquefaction effect is induced, which causes water-permeable materials such as sand and gravel to fully penetrate along the crack cavity, and finally forms a three-dimensionally connected water-conducting skeleton. This water-conducting network not only enhances the air permeability and permeability of the soil, but also regulates the water distribution through capillary action, alleviating the problem of drought or water accumulation. In addition, the sand and gravel filling body is highly stable and is not easy to collapse with the shrinkage and expansion of the soil, which ensures the long-term improvement effect.

[0006] Compared with existing technologies, this method is environmentally friendly, efficient and applicable: it does not require large machinery, is flexible to operate, and is particularly suitable for space-constrained scenarios such as ancient tree protection areas and facility agricultural greenhouses; it is a purely physical action with no risk of chemical pollution; and it is a minimally invasive process that protects the integrity of the surface landscape and is in line with the concept of eco-friendliness. Through the construction of a multi-porous three-dimensional water-conducting network, this technology provides a scalable innovative solution for improving compacted soil.

[0007] In order to achieve the above-mentioned compacted soil improvement implementation effect, the technical solution adopted by the present invention is specifically as follows: First, vertical holes are drilled in a multi-point layout on the surface of compacted soil, using small drilling tools (the hole diameter and depth are adjusted according to the degree of compaction) or other processes to form a minimally invasive channel with controllable depth.

[0008] Secondly, after the hole is formed, water is injected into the hole, and an injection device consisting of a power backstage, an air hose, a hollow guide rod, a directional nozzle and a sealing assembly is inserted. Among them, multiple one-way check plugs are arranged vertically on the outer wall of the hollow guide rod, and the sealing cover on the top of the rod is pressed into the soil layer to realize dynamic sealing of the hole, preventing leakage upward along the inner wall of the hole during the high-pressure air injection process. The backstage power device transmits high-pressure air to the directional nozzle at the bottom of the guide rod through the connecting hose, and directional impacts the soil layer at the bottom of the hole, using kinetic energy to split and form a grid-like crack and cavity channel network that radiates from the bottom of the hole to the surface.

[0009] Furthermore, after the crack cavity is formed, sand and gravel and other granular water-permeable materials are continuously filled into the cavity channel from the surface, and high-pressure air is sprayed in a synchronous cycle and combined with surface water injection. With the help of the instantaneous liquefaction effect caused by the disturbance of high-pressure air flow and water infiltration, the granular material is fully infiltrated and filled along the cracks, forming a three-dimensional water-conducting skeleton, and optimizing the soil moisture distribution through capillary action.

[0010] After the single-hole treatment is completed, the injection device is pulled out, and the remaining cavity in the hole is backfilled to the surface with permeable materials. After repeated operations at multiple holes, the cavity system composed of vertical holes and radial cracks is interconnected, forming a three-dimensional water-conducting network covering the entire area, and the soil infiltration rate is significantly improved.

[0011] This technology achieves soil structure improvement in a non-mechanical tillage manner through the synergistic effects of minimally invasive pore making, high-pressure splitting and sand and gravel filling: directional nozzle and sealing design ensure efficient energy release; permeable skeleton enhances drainage and air permeability; large-scale mechanical operations are avoided throughout the construction process, and surface vegetation and historical landscapes are zero damaged. It is especially suitable for sensitive areas such as ancient tree protection areas and facility agriculture areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0013] Figure 1 The schematic cross-sectional view of an improved technology for splitting and filling compacted soil by high-pressure air jetting according to the present invention at the vertical hole-forming stage shows the process of a hole-forming drill (1) forming a vertical hole (31) in the compacted soil (3); Figure 2 The schematic cross-sectional view of an improved technology for splitting and filling compacted soil by high-pressure air jetting in the present invention is a single-hole high-pressure jetting splitting soil layer stage, showing the structural form of radial cracks and cavity channels (32) formed in the compacted soil (3) by the jetting device (2) through the high-pressure airflow; Figure 3 A schematic diagram of a porous cross-section of an improved technology for splitting and filling compacted soil by high-pressure air jetting according to the present invention after the cavity is filled with a permeable material, showing the spatial distribution of the drainage channel (33) formed by backfilling the cracks and cavity channels (32) with the permeable material (4); Figure 4 This is a schematic flow chart of the implementation steps of a high-pressure air jet compacted soil splitting and filling improvement technology of the present invention, which systematically displays the process of drilling, splitting, filling and water conduction network construction.

[0014] Components in the figure are described as follows: the drilling tool (1) is a construction tool for drilling vertical holes (31); the injection device (2) is a core device, comprising a power backstage (21), an air hose (22), a hollow guide rod (23), a directional nozzle (24), a check plug (25) and a sealing cover (26), and is used for high-pressure air injection and sealing control; the compacted soil (3) is the object of improvement, and after drilling, vertical holes (31) are formed, and after splitting, cracks and cavity channels (32) are generated; the permeable material (4) is a sand and gravel granular body filled in the cavity, and after filling the cracks and cavity channels (32), a drainage channel (33) is formed; water (5) is an auxiliary hole sealing and liquefaction effect triggering medium, and at the same time, the permeable material (4) is transported to fill the cracks and cavity channels (32) and form a drainage channel (33). DETAILED DESCRIPTION

[0015] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0016] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0017] The present invention is described in detail below in conjunction with the accompanying drawings: The present invention provides a high-pressure air jet compacted soil splitting and filling improvement technology, which effectively solves the problems of traditional soil improvement methods causing great damage to the surface and high risk of chemical pollution through a physical minimally invasive method.

[0018] The technology first uses a small drilling tool (1) to drill vertical holes (31) on the surface of compacted soil (3). The diameter and depth of the holes can be flexibly adjusted according to the actual degree of compaction, ensuring the integrity of the surface while creating a channel for subsequent operations. After the hole is formed, water is injected into the hole (5) and an injection device (2) composed of a hollow guide rod (23), a sealing component and a directional nozzle (24) is inserted. The hole (31) is sealed using a one-way check plug (25) and a sealing cover (26) to prevent high-pressure air leakage. The power backstage (21) transmits high-pressure air with a pressure of ≥1MPa to the nozzle (24) through an air hose (22). By accurately controlling the air pressure parameters, the high-pressure air flow is directed from the bottom of the hole to the top to split the soil layer, forming a radial network of cracks and cavity channels (32), providing a three-dimensional space for subsequent filling of permeable materials (4).

[0019] On the basis of constructing a fissure cavity system, the core technical innovation is reflected in the synergistic effect of high-pressure air and granular materials. When the cavity (32) is continuously filled with permeable materials such as sand and gravel (4), high-pressure air is sprayed in a synchronous cycle and combined with surface water injection (5), and the instantaneous liquefaction effect is used to promote the granular material (4) to fully penetrate and fill along the mesh cracks and cavity channels (32). This process not only forms a stable water-conducting skeleton (33) through the pores between the sand and gravel particles, but also optimizes the soil moisture distribution through capillary action, significantly improving the air permeability and permeability. After repeated operations at multiple pores, the water-conducting channels of each pore are interconnected, and finally a three-dimensional drainage network (33) covering the entire area is formed, which fundamentally improves the structure of the compacted soil (3). Compared with traditional tillage technology, this method achieves deep soil improvement through non-mechanical intervention, avoiding damage to plant roots and destruction of the surface landscape.

[0020] The advantage of this technology is that it takes into account both environmental protection and long-term effectiveness. The purely physical effects of high-pressure air splitting and sand and gravel filling eliminate the risk of chemical pollution. The one-way check plug (25) and the sealing cover (26) design ensure concentrated energy release, greatly improving work efficiency. The formed water-conducting network (33) resists soil shrinkage and expansion through the physical stability of the permeable material (4), maintaining a long-term improvement effect. In terms of application scenarios, its minimally invasive characteristics are particularly suitable for sensitive areas such as ancient tree protection areas and historical gardens. It can solve the problem of compacted soil (3) without disturbing the surface vegetation. For facility agricultural parks, this technology can adapt to the limited space environment in the greenhouse. Through the coordinated operation of the injection device (2) and the hole-forming drill (1), the local compacted area can be accurately improved to ensure the healthy growth of the crop root system. Example

[0021] An ancient banyan tree over 300 years old in a historical garden has been trampled by tourists and washed away by rain for a long time. 2 The clay soil in the area was severely compacted, resulting in a sudden drop in soil permeability, the surface rainfall water could not penetrate, the aerial roots of the ancient trees rotted, and the crowns of the trees died. In order to protect this precious cultural heritage, a high-pressure air jet splitting and filling technology proposed by the present invention was used to implement minimally invasive improvement.

[0022] Before construction, the main root distribution was located through physical root detection, and roots with a diameter of more than 5 cm were avoided. Vertical holes were arranged in a 2m×2m grid. Handheld spiral drills (1) were used to drill holes manually. The hole diameter was 10 cm and the depth was 1.5 m. After drilling, clean water was injected to lubricate the hole wall to minimize friction damage to the root system during the drilling process.

[0023] During construction, each hole is inserted with a spray device (2) consisting of a power backstage (21), a gas hose (22) and a hollow guide rod (23). The hole is sealed by a one-way check plug (25) on the outer wall of the guide rod and a top sealing cover (26). After starting the power system, high-pressure air is sprayed at a pressure of 1.2 MPa to the bottom of the soil layer. The directional nozzle (24) concentrates the airflow on the soil layer at the bottom of the hole. The high-pressure splitting for 10 minutes causes radial cracks (32) in the compacted soil. The maximum crack diameter reaches 1.8 m, forming a three-dimensional cavity network with a height of 1.5 m.

[0024] After the cracks are formed, graded coarse gravel sand water-permeable materials (4) with a particle size of 0.5-5 mm are filled into the cavity (32) in layers. High-pressure air is sprayed for 5 seconds every time 30 cm is filled, and water is continuously injected into the surface (5) simultaneously. The instantaneous liquefaction effect produced by the synergistic effect of high-pressure airflow and water causes the graded coarse gravel sand (4) to penetrate downward along the cracks and fully fill the cavity pores (32). After the injection device (2) is pulled out, the remaining hole space (31) is backfilled and compacted with the same material, and the surface is restored to its original appearance. After the construction of all the holes is completed, the water guide channels (33) of each hole are staggered and connected within a depth of 1.5 m underground, forming a three-dimensional drainage skeleton for the entire area.

[0025] After the improvement, the test showed that the permeability coefficient of the original compacted soil increased from 1×10 -7 cm / s increased to 1×10 -6 cm / s or above, and surface waterlogging in the rainy season is completely eliminated. The density of new fine roots in the aerial root decay area around the ancient trees increased by 35%, the crown dieback rate decreased by 22% the following year, and the soil moisture content stabilized in an appropriate range. After two years of follow-up monitoring, the water conduction network filled with coarse gravel and sand did not collapse, and the growth potential of the ancient trees returned to a healthy level. Through precise root-avoiding drilling, high-pressure air directional splitting and coordinated filling of permeable materials, this project achieved dual restoration of compacted soil structure and ecological function without damaging the surface moss community and the roots of ancient trees, providing a reusable technical template for the protection of ancient trees with ultra-deep roots.

[0026] The present invention realizes the minimally invasive improvement of compacted soil without mechanical tillage through the synergistic effect of high-pressure air directional splitting and granular filling. Its technical advantages are mainly reflected in: minimally invasive and environmentally friendly, using small drilling tools to make holes (aperture ≤ 10cm) and air kinetic splitting technology, reducing surface disturbance by more than 90%, avoiding damage to the roots of ancient trees, surface vegetation and historical relics; high efficiency and durability, high-pressure air (≥1MPa) can quickly construct a three-dimensional crack network, and cooperate with sand and gravel filling to form a highly permeable water-conducting skeleton, with permeability increased by more than 10 times and resistance to soil deformation and collapse; precise and controllable, by adjusting air pressure parameters, hole spacing and water injection coordination, customized construction of crack morphology and water-conducting channels can be achieved; broad-spectrum applicability, especially suitable for sensitive scenes such as ancient tree protection areas and facility agricultural areas, and simultaneously improving soil permeability, permeability and water regulation capabilities under the premise of zero chemical pollution, and the improvement effect can be sustained for more than 10 years, providing innovative solutions for soil remediation in ecologically fragile areas.

[0027] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A high-pressure air jet compacted soil splitting and filling improvement technology, characterized in that include: Drill vertical holes on the surface of compacted soil, fill them with water, and then insert the injection device; The holes are closed by sealing components, and high-pressure air is sprayed into the bottom of the holes using nozzles to form a radial network of cracks and cavity channels extending from the bottom of the holes to the surface; simultaneously, the cavities are filled with sand and gravel granular materials and high-pressure air is sprayed in a cycle, and the instantaneous liquefaction effect produced by surface water injection promotes full penetration of the materials to construct a three-dimensional water conduction network; this technology improves soil permeability through minimally invasive physical disturbances, avoiding damage to the surface ecology caused by mechanical tillage.

2. The high-pressure air jet compacted soil splitting and filling improvement technology according to claim 1 is characterized by: The vertical holes are drilled using small drilling tools according to a preset grid layout. The hole diameter and hole depth are dynamically adjusted according to the degree of soil compaction, and are compatible with other hole-making processes.

3. The high-pressure air jet compacted soil splitting and filling improvement technology according to claim 1 is characterized by: The injection device is composed of a power backstage, an air supply hose, a hollow guide rod and a bottom nozzle. A one-way check plug is arranged on the outer wall of the guide rod, which cooperates with the top sealing cover to achieve hole sealing and pressure maintenance.

4. The high-pressure air jet compacted soil splitting and filling improvement technology according to claim 1 is characterized in that: High-pressure air is delivered to the nozzle by the backstage power device through the connecting hose and the hollow guide rod. The depth and shape of the crack expansion are controlled by adjusting the output pressure of the backstage power device to form a multi-directional radial grid-like cavity system.

5. The high-pressure air jet compacted soil splitting and filling improvement technology according to claim 1 is characterized by: The sand and gravel granular body forms a stable three-dimensional water-conducting skeleton after being filled under the synergistic effect of high-pressure air and water injection, and its pore structure enhances soil drainage and air permeability.

6. A high-pressure air jet compacted soil splitting and filling improvement technology according to any one of claims 1 to 5, characterized in that The method comprises the following steps: S1 drilling vertical holes in the area to be improved according to the plane point distribution method; S2 inserting the injection device and sealing the hole, continuously injecting high-pressure air to form a radial crack cavity; S3 continuously filling sand and gravel materials into the cavity, synchronously cyclically injecting high-pressure air and water, and completing the construction of a single-hole water diversion channel; S4 pulling out the injection device and backfilling the remaining cavity in the vertical hole to the surface; S5 repeating the operation of all hole positions to form a three-dimensional water diversion network that is fully connected.

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