Method and apparatus for repairing wind-erosion gullies on earth pile toes

Abstract

The application discloses a method and device for repairing wind-erosion sand pits around pile toes of ground piles, characterized by mixing fibers with desert soil to form fiber-reinforced soil, filling the fiber-reinforced soil into the wind-erosion sand pits around the pile toes of the ground piles until the fiber-reinforced soil is flush with the ground, vertically spraying a biological curing agent treatment liquid on the surface of the filled fiber-reinforced soil by using a spraying device, and finally standing the fiber-reinforced soil to form a hard shell layer on the surface of the fiber-reinforced soil to resist wind erosion, reduce the shaking of the pile toes, and weaken the wind field around the pile toes. The application provides a technology and implementation steps for repairing wind-erosion sand pits around the pile toes of ground piles, uses a biological curing agent treatment liquid mainly composed of a soybean urease solution, can effectively repair the wind-erosion sand pits around the pile toes of desert solar panel ground piles, and can effectively prevent the secondary occurrence of the sand pits. The technology has high economy and durability, does not pollute the environment, and can significantly reduce the maintenance cost of the desert photovoltaic panel.

Description

Technical Field

[0001] This invention relates to the field of desert windbreak and sand control, specifically to a method and apparatus for repairing wind-eroded sand pits at the toes of ground piles. Background Technology

[0002] In today's world, global warming and climate change are major environmental problems. The use of fossil fuels has led to increased greenhouse gas emissions, rising global temperatures, and more frequent extreme weather events. Traditional fossil fuels such as oil, coal, and natural gas are finite resources. With increased extraction and use, these resources are gradually being depleted. With technological advancements, the cost of new energy technologies (such as wind, solar, and hydrogen energy) is gradually decreasing, and their efficiency is continuously improving. This makes new energy sources more economically feasible and promotes their widespread application. In summary, the development of new energy sources is a comprehensive measure to address challenges related to the environment, resources, energy, and security, and it has significant strategic importance.

[0003] Therefore, to thoroughly implement the national strategy of high-quality development, the country is vigorously developing new energy sources, and the rational and full utilization of solar energy has become a top priority. However, during the construction of photovoltaic panels in the desert, we have found that wind erosion pits appear at the toe of the photovoltaic panel piles due to the following reasons. First, desert areas typically have high wind speeds, and strong winds can blow sand from the ground. Second, desert ground is usually composed of loose sand, a geological condition that is easily eroded by wind; as the wind blows across the ground, the sand is carried away. Additionally, desert areas have sparse or almost no vegetation cover, meaning there are no plant roots to anchor the sand, making it easier for the sand to be blown away by the wind. Therefore, under the influence of strong winds, wind erosion pits form near the toe of the photovoltaic panel piles in the desert. Currently, there are no methods in China for repairing or preventing wind erosion pits at the toe of the piles in the desert. Therefore, this invention proposes a technology and implementation steps for repairing wind erosion pits around the toe of the photovoltaic panel piles in the desert. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method and apparatus for repairing wind-eroded sand pits at the toes of ground piles, achieved through the following technical solution:

[0005] A method for repairing wind-eroded sand pits at the toe of ground piles includes the following steps:

[0006] S1) Mixing fibers with desert soil to form fiber-reinforced soil;

[0007] S2) Fill the sand pits formed by wind erosion around the toe of the desert pile with the fiber-reinforced soil until it is level with the ground.

[0008] S3) The bio-curing agent treatment liquid is vertically sprayed onto the filled fiber-reinforced soil surface using a spraying device;

[0009] S4) Static treatment allows a hard shell layer to form on the surface of the fiber-reinforced soil to resist wind erosion, reduce swaying at the pile toe, and weaken the wind field at the pile toe.

[0010] The spraying equipment includes an automatic pothole filling and spraying device, a water hose, a water storage device, and a pump;

[0011] The bio-curing agent treatment solution consists of five components: soybean urease solution, urea-calcium chloride solution, xanthan gum solution, bio-binder solution, and biopolymer solution. The concentration range of each component is (20g / L-100g / L): (0.2mol / L-3mol / L): (0.1g / L-1g / L): (0.6g / L-1.0g / L): (1g / L-3g / L).

[0012] Preferably, the soybean urease solution is obtained from soybeans by grinding, settling, and centrifuging the soybeans; the urea-calcium chloride solution is obtained by mixing urea solution (derived from urea dissolved in water) and calcium chloride solution (derived from calcium chloride dissolved in water) in a 1:1 ratio; the xanthan gum solution is composed of xanthan gum dissolved in water; the bio-gelatinizing agent is a 99% gelatin solution with water as the solvent; the biopolymer is a high molecular weight polysaccharide, and the biopolymer solution is in water as the solvent.

[0013] Preferably, the desert soil is taken from the area where solar panels are built in the desert, and the soil type is aeolian sandy soil and / or gray desert soil; the fiber in the fiber-reinforced soil is formed by one or more of carbon fiber, glass fiber and boron fiber with a mass content of 0.25% carbon fiber, 0.1% glass fiber and 0.2% boron fiber; the mass content is the ratio of fiber mass to desert soil mass.

[0014] Preferably, the automatic pit-filling and spraying device consists of 12 robotic arms, sheet metal pipes, annular water pipes, water outlet valves, wheels, chassis, supports, mixing tanks, connecting pipes, motors, propellers, pipes for conveying soybean urease solution, pipes for conveying urea-calcium chloride solution, pipes for conveying xanthan gum solution, pipes for conveying bio-binders, pipes for conveying biopolymers, and a water stop valve.

[0015] Preferably, the pipe diameters of the pipes for conveying soybean urease solution, urea-calcium chloride solution, xanthan gum solution, bio-binder, and biopolymer are designed using the following flow control formula. By changing the diameters of the five conveying pipes, the flow rates are controlled to achieve the appropriate mixing ratios between different solutions.

[0016]

[0017] In the formula: q v For flow rate, m 3 / s; C is the discharge coefficient, dimensionless; d is the pipe diameter under operating conditions, mm; ΔP x The actual pressure difference is expressed in Pa; ρ is the liquid density in kg / m³. 3 .

[0018] Preferably, during operation, the automatic pit-filling and spraying device is opened along the middle and fitted onto the pile toe. Multiple robotic arms drive the sheet metal pipe to fill the pit with soil from the surrounding area. The sheet metal pipe covers the robotic arms and the ground. After filling, a pump and water hose input five solutions with different pipeline flow rates controlled by the flow control formula into the mixing tank. After mixing, the solutions are transported through a connecting pipe into a ring-shaped water pipe, then into the ring-shaped pipe, and finally out through a water outlet valve on the sheet metal pipe located on the ground. The water outlet valve has an adjustable outlet direction. The connecting pipe connects the mixing tank and the ring-shaped water pipe.

[0019] Preferably, the implementation steps include the following:

[0020] Step 1: Dry soybeans and grind them into soybean powder in a grinder. Dissolve the soybean powder in deionized water at a solid-liquid ratio of 1:50-1:10, stir thoroughly, and let stand for 1 hour until the soybean residue settles. Centrifuge the soybean powder solution and collect the supernatant from the centrifuge tube to obtain a soybean urease solution. Transfer the obtained 20g / L-100g / L soybean urease solution through a conveying pipe into the mixing tank of the automatic filling and spraying device. Transfer 0.2mol / L-3mol / L urea-calcium chloride solution, 0.1g / L-1g / L xanthan gum solution, 0.6g / L-1.0g / L bio-gelling agent solution, and 1g / L-3g / L biopolymer solution into the mixing tank of the device through conveying pipes. After stirring evenly, a bio-curing agent treatment solution is obtained.

[0021] Step 2: Before spraying the treatment liquid, add one or more of the following to the same type of desert soil in the wind erosion depression area around the pile toe: 0.25% carbon fiber, 0.1% glass fiber and 0.2% boron fiber. Mix them evenly to obtain reinforced soil.

[0022] Step 3: Attach the automatic pit filling and spraying device to the pile, place it on the ground, and use the automatic pit filling and spraying device to fill the reinforced soil into the sand pit until the sand pit is level with the surrounding soil.

[0023] Step 4: The water hose is laid in the site, and the automatic pit filling and spraying device is connected to the water hose; the treatment liquid that is evenly mixed in the mixing tank is transported to the spraying site through the water outlet valve on the ground. The automatic pit filling and spraying device is controlled by the water stop valve to automatically spray vertically and evenly around the wind erosion depression area of ​​the pile toe. Each spraying time is 3s-10s.

[0024] The present invention has the following beneficial effects:

[0025] (1) The present invention can directly prepare the biological curing agent treatment liquid on site without the need to prepare the biological curing agent treatment liquid in advance; at the same time, the pit filling and spraying device can realize automatic pit filling and uniform, convenient and automatic spraying, which greatly improves construction efficiency, reduces the maintenance cost of solar photovoltaic panel ground piles, and has high economic benefits.

[0026] (2) The present invention provides a biological curing agent treatment liquid with a specific formulation, and realizes the synchronous adjustment of the ratio between the solutions through a specific flow control formula, which automates the liquid ratio and greatly improves the efficiency of liquid preparation and transportation, especially suitable for the time constraints required for on-site work.

[0027] (3) Compared with traditional curing methods, the biological curing agent of this invention has a superior reinforcement effect, and the maximum penetration strength of the reinforced soil can reach 10 MPa. It has the ability to stabilize and reinforce pile foundations and improve the pile's resistance to collapse. The change in wind field after filling and curing reduces the impact on the piles. At the same time, it can significantly reduce the wind erosion of the solidified soil around the pile foundation. The wind erosion in the first three hours after curing is only 0.02 kg / m³. 3 .

[0028] (4) The components of the biological curing agent treatment liquid of the present invention are widely available and easy to extract. The solution formula with high reinforcement effect is selected and formulated from green and environmentally friendly materials. It is green, environmentally friendly and does not pollute the environment. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating the implementation steps of a technique for repairing wind-eroded sand pits around the toe of a ground pile for a desert solar panel in one embodiment (1, 2, 3) of the present invention.

[0030] Figure 2 This is a schematic diagram of the automated pit-filling and spraying equipment for repairing wind-eroded sand pits around the pile toes of desert solar panel foundation piles in one embodiment (1, 2, 3) of the present invention;

[0031] Figure 3 This is a schematic diagram of the on-site structure of the technology for repairing wind-eroded sand pits around the pile toe of a desert solar panel in one embodiment (1, 2, 3) of the present invention;

[0032] Figure 4 This is a schematic diagram of the pile's resistance to collapse index, illustrating the technique for repairing wind-eroded sand pits around the toe of a ground pile for a desert solar panel in one embodiment (1, 2, 3) of the present invention.

[0033] Figure 5 This is a schematic diagram illustrating the specific effects of the technology for repairing wind-eroded sand pits around the pile toe of a desert solar panel ground pile in one embodiment (1, 2, 3) of the present invention, wherein a higher penetration strength is more beneficial to the stability and reinforcement of the pile.

[0034] The diagram shows: 100 Automatic pit filling and spraying device, 101 Robotic arm, 102 Sheet iron pipe, 103 Circular water pipe, 104 Water outlet valve, 105 Wheels, 106 Chassis, 107 Support, 108 Mixing tank, 110 Connecting pipe, 111 Motor, 112 Propeller, 109 Pipe for conveying soybean urease solution, 113 Pipe for conveying urea-calcium chloride solution, 114 Pipe for conveying xanthan gum solution, 115 Pipe for conveying bio-binder, 116 Pipe for conveying biopolymer, 117 Stop valve, 201 Water hose, 301 Water storage device, 401 Pump, 501 Photovoltaic panel, 601 Pile, and 701 Sand pit. Detailed Implementation

[0035] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention.

[0036] This invention addresses the problem of wind erosion sand pits around the toes of desert solar panel piles by spraying a treatment solution obtained from a mixture of soybean urease solution, salt solution (calcium chloride-urea solution), xanthan gum solution, bio-cementing agent solution, and biopolymer solution onto the soil surface to induce bio-solidification.

[0037] The desert soil described in this invention is soil taken from the area where solar panels are built in the desert. Desert soils are rich in composition, have many types and varieties, and are complex in distribution. The main soil types are aeolian sandy soil and gray desert soil.

[0038] The spraying equipment used in this invention consists of a water hose, an automatic pit-filling and spraying device, a pump, and a water storage device. The spraying device is a novel, automated, and convenient device, comprising 12 robotic arms, a ring-shaped iron pipe for water flow, and several outlet valves. During operation, the device is fitted together around the pile toe. The 12 robotic arms drive the iron pipe covering the robotic arms and the ground to fill the pit with soil from the surrounding area. After repeating the filling process, the pump, through the water hose, pumps the solution through the ring pipe and then through the outlet valves on the iron pipe on the ground, allowing it to flow out evenly and vertically. According to the experimental results of this invention, the specific curing effect of the soybean urease treatment solution spraying is a penetration strength of at least 5 MPa, which stabilizes and reinforces the pile foundation and improves the pile's resistance to collapse. After spraying with the soybean urease treatment solution, the desert wind field is altered, reducing the impact on the piles and the wind erosion of the ground sand.

[0039] The implementation steps of this invention for repairing wind-eroded sand pits around the toe of desert solar panel piles include:

[0040] Step 1: Dry the soybeans and grind them into soybean flour in a grinder. Dissolve the soybean flour in deionized water at a solid-liquid ratio of 1:50-1:10. Stir thoroughly and let stand for 1 hour until the soybean residue settles. Centrifuge the soybean flour solution and take the supernatant from the centrifuge tube to obtain the soybean urease solution. The obtained 20g / L-100g / L soybean urease is fed into the mixing tank 108 of the automatic filling and spraying device 100 through the first delivery pipe 109; 0.2mol / L-3mol / L cementing solution (calcium chloride and urea mixed at a molar ratio of 1:1 as the solute, and water as the solvent), 0.1g / L-1g / L xanthan gum solution (xanthan gum dissolved in deionized water), 0.8g / L bio-cementing agent and 2g / L biopolymer are respectively fed into the mixing tank 108 of the device 100 through the second delivery pipe 113, the third delivery pipe 114, the fourth delivery pipe 115 and the fifth delivery pipe 116, and stirred evenly to obtain the treatment solution.

[0041] Step 2: Before spraying the treatment liquid, carbon fiber, glass fiber, and boron fiber are added to the same type of desert soil in the wind erosion depression area around the pile toe. After mixing evenly, reinforced soil is obtained.

[0042] Step 3: Turn the automatic pit filling and spraying device 100 to the non-working state, put the device on the ground pile and place it on the ground, and use the device to fill the sand pit with reinforced soil until the sand pit is level with the surrounding soil.

[0043] Step 4: The water hose 201 is laid in the site, and the automatic pit filling and spraying device 100 is connected to the water hose 201. The treatment liquid in the mixing tank 108 enters the spraying site through the water outlet valve hole 104, and the spraying device can automatically spray vertically and evenly in the wind erosion depression area of ​​the pile toe.

[0044] The specific examples are illustrated below.

[0045] Example 1

[0046] This embodiment provides an automatic pit-filling and spraying device, the structure of which includes a robotic arm (101), a sheet metal pipe (102), a ring-shaped water pipe (103), a water outlet valve (104), a water hose (201), a water storage device (301), and a pump (401). Figure 1 As shown, the automatic pothole-filling and spraying device is connected to hose 201, and the other end of hose 201 is connected to a pump, which is located in a water storage device. Figure 2 As shown, the automatic pit filling and spraying device consists of two annular water pipes at the top and bottom. The annular water pipes can be opened into two semicircles so that they can be fitted onto the piles. Twelve robotic arms are evenly distributed around the device. The robotic arms and the surface of the lower annular water pipes are all covered with thin iron pipes. Water outlet valves are evenly distributed on the side of the iron pipe at the bottom of the device that is closest to the ground.

[0047] A technique and implementation steps for repairing wind-eroded sand pits around the toes of ground piles for desert solar panels, including:

[0048] Soybeans were dried and ground into soybean flour in a grinder. The soybean flour was dissolved in deionized water at a solid-liquid ratio of 1:50, stirred thoroughly, and allowed to stand for 1 hour to allow the soybean residue to settle. The soybean flour solution was then centrifuged for 15 minutes at 4℃ and 3000 rpm. The supernatant in the centrifuge tube was collected to obtain the soybean urease solution. The urease activity was measured using a conductivity meter (Leici DDB-303A). The results showed that the activity of soybean urease in hydrolyzing urea in this experiment was approximately 6.7 mmol / (L·min) at room temperature (25℃).

[0049] The above-mentioned 20 g / L soybean urease solution, 0.4 mol / L salt solution (calcium chloride-urea solution), 0.2 g / L xanthan gum solution, 0.6 g / L bio-cementing agent solution, and 1 g / L biopolymer solution were respectively fed into the mixing tank of the automatic filling and spraying device through five pipes, and stirred evenly to obtain the treatment solution. The flow rates of the five pipes were in the ratio of 1.3:1.4:2.1:0.2:0.3. The outflow coefficients of the soybean urease solution, salt solution (calcium chloride-urea solution), xanthan gum solution, 0.8 g / L bio-cementing agent solution, and 2 g / L biopolymer solution were 0.8, 0.8, 0.8, 0.6, and 0.5, respectively; the densities of the above five solutions were 1.02 g / cm³. 3 1.07g / cm 3 1.00g / cm 3 2.03 g / cm 3 2.31 g / cm 3 The pipe diameters for the above five solutions are 25mm, 25mm, 25mm, 10mm, and 10mm, respectively.

[0050] Add 4% carbon fiber, 0.2% glass fiber, and 5% boron fiber to the wind-eroded depression area around the pile toe. After mixing evenly, turn the automated pit filling and spraying device to the non-working state, put the device on the pile, place it on the ground, and use the device to fill the sand pit to be level with the surrounding soil.

[0051] Sufficiently long water hoses were laid across the site, and the automatic pit-filling and spraying device was connected to the hoses. At the edge of the site, five 1-ton buckets were filled with the five solutions mentioned above, pumped to a mixing tank using a 3-inch gasoline pump, and then thoroughly mixed. The solutions were then transferred to the spraying area via a connector and a ground-level outlet valve. A robotic arm moved the outlet valve on the bottom metal pipe of the device horizontally across the ground, vertically and evenly spraying the area within 500mm of the pile toe. The spraying range covered all areas within 500mm of the outermost edge of the pile, with each pile toe being sprayed for 12 seconds. Spraying was conducted at 48-hour intervals, once on day 1, day 3, and day 5. After this implementation, the soil penetration strength at the pile toe reached 7.5 MPa.

[0052] Example 2

[0053] Compared with Example 1, the solid-liquid ratio of soybean flour to water is different in this embodiment. This embodiment uses a solid-liquid ratio of 1:25, that is, 40 g / L soybean urease solution, 1 mol / L salt solution (calcium chloride-urea solution), 0.5 g / L xanthan gum solution, 0.8 g / L bio-cementing agent solution, and 2 g / L biopolymer solution. The soil penetration strength of this embodiment reaches 9 MPa.

[0054] Example 3

[0055] Compared to Example 1, this embodiment differs in the solid-liquid ratio of soybean flour to water. This embodiment uses a 1:10 solid-liquid ratio, i.e., a 100 g / L soybean urease solution, a 2 mol / L salt solution (calcium chloride-urea solution), a 1 g / L xanthan gum solution, a 1 g / L bio-cementing agent solution, and a 3 g / L biopolymer solution. In this embodiment, the soil penetration strength reaches 10 MPa.

[0056] Comparative Example 1

[0057] This comparative example did not add xanthan gum additives, bio-cementing agent solutions, or biopolymer solutions to the soybean urease cementing solution; the remaining components were identical to those in Example 1. The soil penetration strength in this example reached 5 MPa.

[0058] Comparative Example 2

[0059] This comparative example did not add xanthan gum additives, bio-cementing agent solutions, or biopolymer solutions to the soybean urease cementing solution; the remaining components were identical to those in Example 2. The soil penetration strength in this example reached 6 MPa.

[0060] Comparative Example 3

[0061] This comparative example did not add xanthan gum additive, bio-cementing agent solution, or biopolymer solution to the soybean urease cementing solution; the remaining components were exactly the same as in Example 3. The soil penetration strength in this example reached 7.5 MPa.

[0062] Comparative Example 4

[0063] The difference between this comparative example and Comparative Example 3 lies in the number of sprayings. The spraying interval was 48 hours, with spraying occurring once on day 1 and once on day 3. Compared to Example 3, the penetration strength of this soil was 6 MPa. This was because insufficient spraying volume led to a decrease in the penetration strength of the soil.

[0064] The foregoing has shown and described 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 embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for repairing wind-eroded sand pits at the toe of ground piles, characterized in that, Includes the following steps: S1) Mixing fibers with desert soil to form fiber-reinforced soil; S2) Fill the sand pits formed by wind erosion around the toe of the desert pile with the fiber-reinforced soil until it is level with the ground. S3) The bio-curing agent treatment liquid is vertically sprayed onto the filled fiber-reinforced soil surface using a spraying device; S4) Static treatment allows a hard shell layer to form on the surface of the fiber-reinforced soil to resist wind erosion, reduce swaying at the pile toe, and weaken the wind field at the pile toe. The spraying equipment includes an automatic crater filling and spraying device (100), a water hose (201), a water storage device (301), and a pump (401); the automatic crater filling and spraying device (100) is connected to the water hose (201), and the other end of the water hose (201) is connected to the pump (401), wherein the pump is located in the water storage device (301); The bio-curing agent treatment solution consists of five components: soybean urease solution, urea-calcium chloride solution, xanthan gum solution, bio-binder solution, and biopolymer solution. The concentration range of each component is 20g / L-100g / L; 0.2mol / L-3mol / L; 0.1g / L-1g / L; 0.6g / L-1.0g / L; 1g / L-3g / L. The soybean urease solution is obtained from soybeans by grinding, settling, and centrifuging the soybeans; the urea-calcium chloride solution is obtained by mixing urea solution (derived from urea dissolved in water) and calcium chloride solution (derived from calcium chloride dissolved in water) in a 1:1 ratio; the xanthan gum solution is obtained by dissolving xanthan gum in water; the bio-gelatinizing agent is a 99% gelatin solution with water as the solvent; the biopolymer is a high molecular weight polysaccharide, and the biopolymer solution is in water as the solvent; The automatic pit filling and spraying device (100) consists of a robotic arm (101), a sheet metal pipe (102), a ring-shaped water pipe (103), a water outlet valve (104), wheels (105), a chassis (106), a support (107), a mixing tank (108), a connecting pipe (110), a motor (111), a propeller (112), a pipe for conveying soybean urease solution (109), a pipe for conveying urea-calcium chloride solution (113), a pipe for conveying xanthan gum solution (114), a pipe for conveying bio-binder (115), a pipe for conveying biopolymer (116), and a stop valve (117). The automatic pit filling and spraying device (100) consists of two annular water pipes at the top and bottom. During operation, the annular water pipes are opened into a semi-circle to fit around the pile toe. Multiple robotic arms (101) drive the sheet metal pipe (102) to fill the soil around the pit into the pit. The sheet metal pipe (102) covers the robotic arms and the ground. After filling, the pump (401) and water hose (201) input soybean urease solution, urea-calcium chloride solution, xanthan gum solution, bio-binder solution and biopolymer solution into the mixing tank (108). After mixing, the solution is transported through the connecting pipe (110) into the annular water pipe (103), and then flows out through the water outlet valve (104) on the sheet metal pipe (102) located on the ground. The water outlet valve (104) has an adjustable water outlet direction. The connecting pipe (110) connects the mixing tank (108) and the annular water pipe (103).

2. The method for repairing wind-eroded sand pits at the toe of ground piles according to claim 1, characterized in that: The desert soil is taken from the area where solar panels are built in the desert, and the soil type is aeolian sandy soil and / or gray desert soil; the fiber in the fiber-reinforced soil is formed by one or more of the following: 0.25% carbon fiber, 0.1% glass fiber and 0.2% boron fiber; the mass content is the ratio of fiber mass to desert soil mass.

3. The method for repairing wind-eroded sand pits at the toe of ground piles according to claim 1, characterized in that, The pipe diameters of the pipes (109) for conveying soybean urease solution, (113) for conveying urea-calcium chloride solution, (114) for conveying xanthan gum solution, (115) for conveying bio-cementing agent, and (116) for conveying biopolymer are designed using the following flow control formula. By changing the diameters of the five conveying pipes, the flow rates are controlled to achieve the appropriate mixing ratios between different solutions. In the formula: q v For flow rate, m 3 / s; C is the discharge coefficient, dimensionless; d is the pipe diameter under operating conditions, mm; ΔP x The actual pressure difference is expressed in Pa; ρ is the liquid density in kg / m³. 3 .

4. The method for repairing wind-eroded sand pits at the toe of ground piles according to claim 1, characterized in that, Specifically, the following steps are included: Step 1: Dry soybeans and grind them into soybean flour in a grinder. Dissolve the soybean flour in deionized water at a solid-liquid ratio of 1:50-1:10, stir thoroughly, and let stand for 1 hour until the soybean residue settles. Centrifuge the soybean flour solution and collect the supernatant from the centrifuge tube to obtain soybean urease solution. Transfer the obtained 20g / L-100g / L soybean urease solution through the soybean urease solution conveying pipe (109) into the mixing tank (108) of the automatic pit filling and spraying device (100). Add 0.2mol / L-3mol / L... Urea-calcium chloride solution, xanthan gum solution (0.1 g / L-1 g / L), bio-cementitious agent solution (0.6 g / L-1.0 g / L), and biopolymer solution (1 g / L-3 g / L) are respectively transported into the mixing tank (108) of the automatic pit filling and spraying device (100) through the pipeline (113) for transporting urea-calcium chloride solution, the pipeline (114) for transporting xanthan gum solution, the pipeline (115) for transporting bio-cementitious agent, and the pipeline (116) for transporting biopolymer. After being stirred evenly, a bio-curing agent treatment solution is obtained. Step 2: Before spraying the treatment liquid, add one or more of the following to the same type of desert soil in the wind erosion depression area around the pile toe: 0.25% carbon fiber, 0.1% glass fiber and 0.2% boron fiber. Mix them evenly to obtain reinforced soil. Step 3: Place the automatic filling and spraying device (100) on the pile and put it on the ground. Use the automatic filling and spraying device (100) to fill the reinforced soil into the sand pit until the sand pit is level with the surrounding soil. Step 4: The water hose (201) is laid in the site, and the automatic pit filling and spraying device (100) is connected to the water hose (201); the treatment liquid that is evenly stirred in the mixing tank (108) is transported to the spraying site through the water outlet valve (104) on the ground, and the automatic pit filling and spraying device (100) is controlled by the water stop valve (117) to automatically spray vertically and evenly around the wind erosion depression area of ​​the pile toe, with each spraying time being 3s-10s.

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