MICP biological curing high side friction pervious concrete pile and construction method

Abstract

According to the MICP biological curing pervious concrete pile and the construction method thereof, appropriate microorganisms and cementing liquid are sprayed to the surface of a pile body, urease is generated through metabolism of the microorganisms to catalyze carbonate salting-out reaction, and a firm calcium carbonate filling and cementing material is generated on a pile-soil interface; the surface roughness of the pervious concrete pile is increased, so that the pile-soil interface frictional resistance is improved, more loads are transmitted to a soil body by improving the pile body side frictional resistance, the soil body can bear the more loads, the bearing effect of a composite foundation is achieved to the maximum extent, and the bearing capacity of the composite foundation is effectively improved. Biological slurry is evenly adsorbed on the surface of the side wall of the pile body through the adsorption performance of activated carbon, the purpose of even curing is achieved, the biological slurry permeates into the pile body through the rough surface of the side wall of the pervious concrete pile and pores, a calcium carbonate body generated through internal reaction plays a role similar to an anchor rod, and the external calcium carbonate body is firmly fixed; and finally, a stable side wall calcium carbonate high-friction-resistance reinforcement body is formed.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a green and environment-friendly MICP bio-solidified high lateral friction resistance permeable concrete pile and a construction method thereof. Background Art

[0002] Composite foundation treatment technology is a widely used technology in foundation reinforcement of buildings, roads, railways and other sites, and is an important part of geotechnical engineering technology. This technology forms a vertical reinforcement body (pile body) by strengthening or replacing part of the soil, so that it and the surrounding soil can share the upper load and improve the bearing capacity of the foundation. Conventional bored piles in composite foundation treatment usually have pile body quality problems such as hole collapse and neck shrinkage, and the sides of ordinary bored piles are relatively smooth and the side friction resistance is small, resulting in insufficient bearing capacity of the pile body and composite foundation. Due to the poor bearing capacity of the weak foundation, in order to meet the bearing capacity design requirements during treatment, it is often necessary to increase the pile length or increase the pile diameter, which increases the difficulty of design and construction and increases construction costs.

[0003] Precast piles have the advantages of good pile body molding quality, high strength, economical price, simple construction and low impact of static pressure construction on the surrounding environment. Therefore, they are widely used in foundation treatment. However, ordinary precast concrete piles also have the problems of smooth pile surface, small pile body side friction and insufficient bearing capacity. At present, there are two ways to solve the problem of insufficient side friction of precast piles. One is to grout the pile side and pile end, and use slurry to strengthen the connection strength between the pile body and the soil layer around the pile. However, there are problems such as large amount of slurry and uneven diffusion of slurry, poor treatment effect and soil pollution; the other is to change the pile structure to strengthen the side friction, but there are disadvantages such as difficult manufacturing process, difficult pile sinking and high cost, which makes it difficult to promote and apply.

[0004] In recent years, microbial induced calcium carbonate precipitation (MICP) has attracted extensive attention as a new, green and environmentally friendly soil reinforcement technology in geotechnical engineering. MICP technology mainly utilizes the metabolic function of microorganisms that are widely present in nature to secrete a urease, which undergoes a series of biochemical reactions with other substances in the environment to form a solid calcium carbonate cementation and filling material, changing the physical mechanics and engineering properties of the soil, thereby achieving the purpose of environmental purification, soil repair and foundation reinforcement. MICP technology has been widely studied in indoor experiments; however, field tests and model tests have always faced practical difficulties such as biological clogging around the injection point (i.e., stabilizing the limited area around the injection point) and uneven solidification, which limits its application in foundation treatment. Summary of the invention

[0005] In view of the problems and shortcomings of the prior art, the purpose of the present invention is to provide a green and environmentally friendly MICP bio-solidified permeable concrete pile technology and its construction method. The present invention utilizes the characteristics of MICP biological slurry to improve and strengthen the side wall of the pile body, and improves the side friction resistance and bearing capacity of the pile through the calcium carbonate crystals produced by the mineralization reaction. First, an automatic pressure spraying device is used to evenly spray the activated carbon solution to provide attachment sites for the growth of microorganisms, and then the microbial solution and the cementing liquid are sprayed separately, in order to control the reaction time, so that the biomineralization reaction can be carried out stably on the side wall of the pile body, and the actual difficulty of biological blockage of the spray head during the construction process is prevented, and the construction is carried out smoothly.

[0006] To achieve the purpose of the invention, the technical solution adopted by the present invention is as follows:

[0007] In the first aspect, the present invention discloses a MICP bio-cured permeable concrete pile, which is composed of a cylindrical prefabricated permeable concrete pile and a calcium carbonate reinforcement generated by reaction on the periphery and inside of the prefabricated permeable concrete pile; the prefabricated conventional permeable concrete pile is made of permeable concrete, and there are a large number of interconnected pores in the pile body; the permeable pile body is cylindrical, the side wall surface of the pile body is porous and rough, and has a slurry dispersion flow channel.

[0008] In a second aspect, the present invention further provides a construction method of a MICP biosolidified permeable concrete pile, comprising the following steps:

[0009] Step 1: Drill a pile hole at the pile position on the construction site;

[0010] Step 2: Press the spray sleeve into the pile hole to the specified depth;

[0011] Step 3: implant the prefabricated permeable concrete pile into the sleeve to the specified depth;

[0012] Step 4, preparing microbial slurry, cementing liquid and green material activated carbon solution;

[0013] Step 5: Evenly spray the green material activated carbon solution on the surface of the permeable concrete pile and let it stand for a set time; the activated carbon evenly adheres to the surface of the pile and penetrates into the interior of the pile;

[0014] Step 6: Spray the microbial solution with good activity evenly on the surface of the permeable concrete pile; let it stand for a set time, a large number of microorganisms are evenly adsorbed on the surface of the pile by the activated carbon, and a small amount of microorganisms penetrate into the interior of the pile;

[0015] Step 7, spraying the cementing liquid evenly on the surface of the permeable concrete pile; the cementing liquid is evenly adsorbed by the activated carbon on the surface of the pile body and contacts with microorganisms, and the mineralization reaction begins to proceed stably;

[0016] Step 8. Remove the pressure spraying sleeve to make the permeable concrete pile body in close contact with the soil. A large amount of calcium carbonate generated by the mineralization reaction on the surface of the pile body will cement the pile body and the soil around the pile. A small amount of calcium carbonate generated in the pores inside the pile body will act like an anchor to form a calcium carbonate consolidation body at the pile-soil interface, thus forming a stable high-side friction resistance reinforcement body.

[0017] As a further technical solution, the spray sleeve described in step 2 includes an inner layer and an outer layer, and the inner wall of the sleeve is evenly distributed with a plurality of spray heads along its height and circumferential direction.

[0018] As a further technical solution, the microorganism selected in the microbial solution is a well-active Bacillus pasteurianus, which can stably secrete urease, catalyze the hydrolysis of urea in the cementing liquid, generate calcium carbonate ions, and then combine with calcium ions to produce calcium carbonate precipitation. The activity of Bacillus pasteurianus is related to factors such as time, temperature and pH, so the biomineralization reaction process is controllable.

[0019] As a further technical solution, the binder is prepared by uniformly mixing anhydrous calcium chloride and urea with deionized water in a ratio of 1:1.

[0020] As a further technical solution, the diameter of the pile hole in step 1 is smaller than or equal to the diameter of the spray sleeve, and the spray sleeve is implanted into the pile hole by static pressure or vibration.

[0021] As a further technical solution, in step 2, a crane is used to lift the prefabricated permeable concrete pile into the sleeve.

[0022] As a further technical solution, in step 5, step 6 and step 7, an automated pressure spraying device is used for spraying.

[0023] As a further technical solution, the automated pressure spraying device includes a control module, a pressure sensor, a flow sensor and a solution delivery module. The control module controls the solution delivery module according to data detected by the pressure sensor and the flow sensor.

[0024] As a further technical solution, activated carbon solution is prepared by mixing green material activated carbon with deionized water. It is non-toxic and harmless and has a highly porous structure, providing a large surface area and microporous structure, which is conducive to the attachment and growth of microorganisms.

[0025] Compared with the prior art, the present invention has the following positive and beneficial effects:

[0026] (1) The present invention provides a high lateral friction pile formed by bio-grouting reinforced permeable concrete pile using microbial induced carbonate deposition (MICP) technology and a construction method thereof. The method utilizes the combined effects of microbial activity and chemical reaction to form a solid mineralized calcium carbonate cementation body in the internal pores of the permeable concrete pile and the pile-soil interface, thereby enhancing the lateral friction resistance and pile body strength of the permeable concrete pile, thereby improving the bearing capacity of single piles and composite foundations and reducing foundation settlement.

[0027] (2) The pile body is first sunk and then strengthened by spraying biological slurry. Before the biological slurry is sprayed, the pile body will not be physically changed, and the pile sinking process is simple and convenient. The two slurries are sprayed separately at the same time to ensure that the slurry will not react and clog the spray head during the spraying process. By setting a spray sleeve and an automated pressure spraying device, the spray sleeve and the automated pressure spraying device cooperate with each other to ensure the uniformity of the pile curing.

[0028] (3) Prefabricated permeable concrete piles are used as the main body of biological grouting reinforcement. Compared with traditional prefabricated plain concrete piles, prefabricated permeable concrete piles with permeation channels can ensure that the biological slurry can penetrate all directions from the outside to the inside, achieve uniform distribution of the biological slurry, ensure the reinforcement effect, save time and cost. The technology of prefabricated permeable concrete piles is mature and can ensure the quality of the pile body and the pile effect after grouting reinforcement.

[0029] (4) The shotcrete enhancement technology used in the present invention has certain cost advantages compared to traditional pouring grouting. The construction process is relatively simple. It only requires the selection of appropriate microbial strains and calcium sources for injection, and does not require large-scale earthwork, saving time and cost. In addition, the cost of microbial strains and calcium source materials used in MICP biological grouting is relatively low, which helps to reduce the overall construction cost.

[0030] (5) Compared with the traditional chemical grouting method, green MICP biological grouting does not require the use of chemical agents. Through the metabolic action of microorganisms, urease catalyzes the production of calcium filling cementing materials. The added auxiliary green material activated carbon provides a uniform attachment site for the growth of microorganisms and the deposition of calcium carbonate. It also absorbs a small amount of carbon dioxide gas during the reaction process, which is harmless to the soil and the environment. Therefore, this patented solution has the advantage of environmental sustainability.

[0031] (6) The MICP biological grouting process has a high degree of controllability. It can select microbial strains, control nutrient culture media, adjust bacterial liquid concentration and activity, and control external environmental factors according to the actual situation of the foundation and engineering requirements. By using appropriate microorganisms and adjusting peristaltic pump parameters, precise control of pressure and flow during the biological injection process can be achieved to achieve the desired strengthening effect.

[0032] (7) The green and environmentally friendly MICP bio-grouting high lateral friction resistance pile is suitable for various soft foundation types, including clay, sand and silt, and can meet the needs of different regions and different engineering conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the vertical cross-sectional structure of the green and environmentally friendly MICP biological grouting high lateral friction pile of the present invention;

[0034] Figure 2 A front view of a pressure shotcrete sleeve customized for the present invention;

[0035] Figure 3 A top view of a pressure shotcrete sleeve customized for the present invention;

[0036] Figure 4 It is a schematic diagram of the construction process of the green and environmentally friendly MICP biological grouting high lateral friction resistance pile of the present invention.

[0037] In the figure, 1 is a prefabricated permeable concrete pile, 2 is the surrounding soil, 3 is a customized pressure spraying sleeve, 3-1 is a spraying head, 3-2 is a grouting port, 4 is a grouting hose, 5 is an automated pressure spraying device, and 6 is a grouting liquid. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below through specific examples, but the scope of the present invention is not limited thereto.

[0039] In order to solve the problem of insufficient side friction of cast-in-place piles and precast piles commonly used in foundation treatment projects, it is urgently necessary to invent a technology and construction method that can effectively enhance the side friction and bearing capacity of the piles and has the advantages of being green, environmentally friendly and pollution-free.

[0040] This embodiment discloses a MICP biological grouting high lateral friction pile, such as Figure 1 , Figure 2 As shown, it is composed of a cylindrical prefabricated permeable concrete pile 1 and a calcium carbonate reinforcement 2 generated by reaction on the periphery and inside of the prefabricated permeable concrete pile 1. The inner diameter, outer diameter, wall thickness and height of the custom-made construction sleeve are selected according to the design requirements.

[0041] At the same time, the construction equipment of the above-mentioned green and environmentally friendly MICP bio-cured permeable concrete piles includes a customized pressure spraying sleeve 2, a grouting hose 4, and an automated pressure spraying device 5; the corresponding construction materials include prefabricated permeable concrete piles, a microbial solution with good activity, a binder with optimal concentration, and green auxiliary material activated carbon; the microbial solution with good activity, the binder with optimal concentration, and the green auxiliary material activated carbon correspond to the grouting liquid 6 in the figure.

[0042] The above-mentioned prefabricated permeable concrete pile is a circular cross-section pile made of permeable concrete. The pile diameter, pile length and strength grade of the prefabricated permeable concrete pile can be designed and determined according to on-site requirements.

[0043] The above-mentioned automatic pressure spraying device 5 is mainly composed of a solution flow intelligent control module, a pressure module, a solution delivery module and a spray sleeve, etc.; wherein the solution flow intelligent control module monitors and adjusts the flow of the grouting solution in real time, and performs intelligent adjustment when necessary, and the module includes components such as a flow sensor, a controller and an actuator. The flow sensor is used to monitor the flow of the grouting solution in real time and transmit the data to the controller; the controller performs calculations and analyses according to preset parameters and algorithms, and then adjusts the pressure pump through the actuator to achieve intelligent control of the solution flow.

[0044] The above-mentioned pressure module includes a pressure sensor and a data collector. The pressure sensor is used to monitor the pressure changes in the grouting pipe or grouting pump in real time and transmit the collected data to the data collector; the controller calculates and analyzes according to the preset pressure range and algorithm, and then adjusts the pressure pump through the actuator to realize the monitoring and control of the grouting pressure.

[0045] The solution delivery module mentioned above is mainly responsible for delivering the pre-prepared grouting solution from the storage container to the grouting point. The module includes components such as a pressure pump, a pipeline system, a valve, and a flow meter. The pump is a key device for delivering grouting solution. It can provide sufficient pressure to deliver the solution from the starting point to the target location. The pipeline system is responsible for connecting various delivery points to ensure that the solution can flow smoothly. The function of the valve is to regulate and control the flow of the solution. The flow meter is used to monitor and record the delivery volume of the solution to help grasp the real-time delivery situation.

[0046] The above-mentioned spray sleeve is made of steel. The sleeve is divided into two layers, an inner layer and an outer layer. A grouting hose connected to a spray head is placed in the space between the two layers. The spray heads are evenly distributed on the inner wall of the sleeve.

[0047] The microorganism in the above-mentioned microbial solution with good activity is Bacillus pasteurianus, which is a strain with high urease production and strong adaptability to the environment. The bacteria are rod-shaped and the spores are round with a diameter of 0.5 to 1.5 μm.

[0048] The above-mentioned Bacillus pasteurianus is stored in an ampoule in the form of freeze-dried powder. Before use, the cultured bacteria need to be activated using a liquid culture medium until the activity value of the Bacillus pasteurianus solution meets the use requirements.

[0049] The above-mentioned cementing liquid is prepared by uniformly mixing anhydrous calcium chloride and urea with deionized water in a ratio of 1:1, and the optimal solubility of the cementing liquid is 1.5 mol / L.

[0050] The above green material activated carbon is non-toxic, harmless, green and environmentally friendly, and has no negative impact on the human body and the environment;

[0051] The above-mentioned green material activated carbon has a highly porous structure, which provides a large surface area and pore structure, which is conducive to the attachment and growth of microorganisms; the high adsorption properties of the activated carbon surface can adsorb and concentrate calcium ions or carbonate ions in the cementing fluid, and can also absorb a small amount of carbon dioxide generated during the reaction.

[0052] The above-mentioned green and environmentally friendly MICP bio-solidified permeable concrete pile construction method is specifically as follows: Figure 4 As shown, the specific steps include:

[0053] Step 1: drilling a hole at the pile position by using a drilling rig to obtain a pile hole, the depth of which is the same as the designed pile bottom elevation;

[0054] Step 2: sinking the pipe, pressing the spray sleeve in the automated pressure spraying device into the pile hole to a depth specified by the design; specifically, the spray sleeve is implanted into the pile hole by static pressure or vibration;

[0055] Step 3 is pile sinking. The prefabricated permeable concrete pile 1 is lowered into the spray sleeve by a crane. The prefabricated permeable concrete pile 1 is a circular cross-section pile made of permeable concrete. The diameter and strength grade of the prefabricated permeable concrete pile 1 are selected according to design requirements. The pile body is first sunk and then strengthened by spraying biological slurry. No physical changes are made to the pile body before the biological slurry is sprayed. The pile sinking process is simple and convenient.

[0056] Prefabricated permeable concrete piles are used as the main body of biological grouting reinforcement. Prefabricated permeable concrete piles with penetration channels can ensure that the biological slurry can penetrate all directions from the outside to the inside, achieve uniform distribution of the biological slurry, ensure the reinforcement effect, save time and cost. The technology of prefabricated permeable concrete piles is mature and can ensure the quality of the pile body and the pile effect after spraying reinforcement.

[0057] Step 4: Prepare activated carbon solution biological slurry. The selected microorganism is Bacillus pasteurianus. First, the microorganism needs to be expanded and cultured to prepare a liquid culture medium, inoculated with Bacillus pasteurianus with good activity, and the external environment is suitable for pH and temperature until its activity reaches the optimal value; the cementing liquid is prepared by mixing calcium chloride and urea in proportion, and the optimal cementing liquid concentration is used;

[0058] Step 5: After the activated carbon, microbial slurry and cementing liquid are prepared according to the design requirements, Figure 4An automated spraying device is used to first evenly divide the activated carbon solution into two stages, and the microbial slurry and the binder are injected into the spray head connecting hose for spraying. The activated carbon is evenly attached to the surface of the pile and penetrates into the interior of the pile. The peristaltic pump used can control the appropriate spraying rate and spraying pressure. In the first stage, the microbial slurry is sprayed to quickly fill the pores on the side walls of the pile and penetrate into the interior of the pile. The microorganisms are evenly adsorbed on the surface of the pile by the activated carbon, and a small amount of microorganisms penetrate into the interior of the pile. In the second stage, the binder is sprayed to cover the microbial slurry and provide a calcium source for the stable mineralization reaction, so that it penetrates evenly along the connected pores inside the permeable concrete pile, and finally reacts at the pile-soil interface and the pores inside the pile to generate calcium carbonate reinforcement until the design requirements are met. The two slurries are sprayed separately to ensure that the slurry does not react and clog the spray head during the spraying process.

[0059] Step 6 After the biological slurry is completely infiltrated, the peristaltic machine is removed and the curing is carried out according to the design time. Specifically, the pressure spraying sleeve is removed to make the permeable concrete pile body in close contact with the soil body. A large amount of calcium carbonate generated by the mineralization reaction on the surface of the pile body cements the pile body and the soil body around the pile. A small amount of calcium carbonate generated in the pores of the pile body acts like an anchor to firmly fix the pile-soil interface to form a calcium carbonate consolidation body, thereby forming a stable high lateral friction resistance reinforcement body.

[0060] The activity of microorganisms changes with the reaction time; when using green and environmentally friendly MICP biological grouting high-side friction resistance piles for on-site engineering applications, the grouting speed and curing time should be reasonably designed to achieve better results.

[0061] As the temperature rises, bacteria become more active and will continuously secrete urease. As the urease concentration increases, the urease hydrolysis reaction rate also accelerates accordingly. When green and environmentally friendly MICP biological grouting high-side friction resistance piles are used in on-site engineering applications, better results can be achieved in construction during the high temperature summer.

[0062] With the increase of pH value, the activity value of Bacillus pasteurianus showed a trend of first increasing, then fluctuating and finally gradually decreasing. When using green and environmentally friendly MICP biological grouting high side friction piles for field engineering applications, preparing biological slurry within the appropriate pH value range can achieve better results.

[0063] The high lateral friction piles formed by bio-grouting reinforced permeable concrete piles using the microbial induced carbonate deposition (MICP) technology and the construction method thereof; the method utilizes the combined effects of microbial activity and chemical reaction to form a solid mineralized calcium carbonate cementation body in the internal pores of the permeable concrete pile and at the pile-soil interface, thereby enhancing the lateral friction resistance and pile body strength of the permeable concrete pile, thereby improving the bearing capacity of single piles and composite foundations and reducing foundation settlement.

[0064] In the above-mentioned construction method, the spraying enhancement technology used has certain cost advantages compared to traditional pouring grouting. The construction process is relatively simple. It only requires the selection of suitable microbial strains and calcium sources for injection. Large-scale earthwork is not required, which saves time and cost. In addition, the cost of microbial strains and calcium source materials used in MICP biological grouting is relatively low, which helps to reduce the overall construction cost. Compared with the traditional chemical grouting method, green MICP biological grouting does not require the use of chemical agents. Through the metabolic action of microorganisms, urease catalyzes the production of calcium filling cementitious materials. The added auxiliary green material activated carbon provides a uniform attachment site for the growth of microorganisms and the deposition of calcium carbonate. It also absorbs a small amount of carbon dioxide gas during the reaction, which is harmless to the soil and the environment. Therefore, this patented solution has the advantage of environmental sustainability.

[0065] The MICP biological grouting process has a high degree of controllability. It can select microbial strains, control nutrient culture media, adjust bacterial liquid concentration and activity, and control external environmental factors according to the actual situation of the foundation and engineering requirements. By using appropriate microorganisms and adjusting peristaltic pump parameters, it is possible to accurately control the pressure and flow rate during the biological injection process to achieve the desired strengthening effect.

[0066] The green and environmentally friendly MICP bio-grouting high lateral friction resistance pile is suitable for various soft foundation types, including clay, sand and silt, and can meet the needs of different regions and different engineering conditions.

[0067] The above description is only a preferred embodiment of the present invention, but is not limited to the above examples. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. MICP bio-cured permeable concrete pile, characterized in that: Prefabricated cylindrical permeable concrete Concrete piles are composed of calcium carbonate reinforcements generated by reaction on the periphery and interior of prefabricated permeable concrete piles.

2. The construction method of the MICP biosolidification permeable concrete pile according to claim 1, Its characteristics are The method comprises the following steps: Step 1: Drill a pile hole at the pile position on the construction site; Step 2: Press the spray sleeve into the pile hole to the specified depth; Step 3: implant the prefabricated permeable concrete pile into the sleeve to the specified depth; Step 4, preparing microbial slurry, cementing liquid and green material activated carbon solution; Step 5: Evenly spray the green material activated carbon solution on the surface of the permeable concrete pile and let it stand for a set time; the activated carbon evenly adheres to the surface of the pile and penetrates into the interior of the pile; Step 6: Spray the microbial solution with good activity evenly on the surface of the permeable concrete pile; let it stand for a set time, a large number of microorganisms are evenly adsorbed on the surface of the pile by the activated carbon, and a small amount of microorganisms penetrate into the interior of the pile; Step 7, spraying the cementing liquid evenly on the surface of the permeable concrete pile; the cementing liquid is evenly adsorbed by the activated carbon on the surface of the pile body and contacts with microorganisms, and the mineralization reaction begins to proceed stably; Step 8. Remove the pressure spraying sleeve to make the permeable concrete pile body in close contact with the soil. A large amount of calcium carbonate generated by the mineralization reaction on the surface of the pile body will cement the pile body and the soil around the pile. A small amount of calcium carbonate generated in the pores inside the pile body will act like an anchor to form a calcium carbonate consolidation body at the pile-soil interface, thus forming a stable high-side friction resistance reinforcement body.

3. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that In step 2, the spraying sleeve comprises an inner layer and an outer layer, and a plurality of spraying heads are evenly distributed on the inner wall of the sleeve along its height and circumferential direction.

4. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that In the microbial solution, the microorganism selected is Bacillus pasteurianus.

5. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that The binder is prepared by uniformly mixing anhydrous calcium chloride and urea with deionized water in a ratio of 1:

1.

6. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that In step 1, the diameter of the pile hole is smaller than or equal to the diameter of the spray sleeve, and the spray sleeve is implanted into the pile hole by static pressure or vibration.

7. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that Therefore, in step 2, a crane is used to lift the prefabricated permeable concrete pile into the sleeve.

8. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 2, characterized in that In step 5, step 6 and step 7, an automated pressure spraying device is used for spraying.

9. The construction method of MICP biosolidification permeable concrete pile as claimed in claim 8, characterized in that The automatic pressure spraying device includes a control module, a pressure sensor, a flow sensor and a solution delivery module. The control module controls the solution delivery module according to data detected by the pressure sensor and the flow sensor.

10. The construction method of MICP bio-solidified permeable concrete pile according to claim 2, characterized in that: The activated carbon solution is prepared by mixing green material activated carbon with deionized water.

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