Device for reinforcing cast-in-place pile foundation in sandy soil stratum

Abstract

The utility model discloses a device for reinforcing a cast-in-place pile foundation in a sandy soil stratum, which comprises a grouting control system and an intelligent control system, the grouting control system comprises a grouting pump arranged on the ground surface and a grouting pipe buried in the ground, and the top of the grouting pump is respectively communicated with a bacterial liquid storage tank and a nutrient solution storage tank through a multi-channel switching valve; the grouting pump inputs grout into the grouting pipe through a communicating pipeline, a flow meter is arranged on the communicating pipeline, and a pressure sensor is arranged at the joint of the communicating pipeline and the grouting pipe; the flow meter, the grouting pump and the pressure sensor are all electrically connected with the intelligent control system. A thermal insulation layer covers the ground surface around the pipe orifice of the grouting pipe and is electrically connected with the intelligent control system; according to the device, the side friction resistance of the pile foundation and the soil body is improved through the MICP technology, and the grouting control system and the intelligent control system are matched with each other to reinforce the cast-in-place pile foundation used in the sandy soil stratum.

Description

Technical Field

[0001] This utility model relates to the field of microbial reinforcement technology, and in particular to a device for reinforcing cast-in-place pile foundations in sandy soil strata. Background Technology

[0002] Bio-induced calcium carbonate crystallization (MICP) technology involves injecting specific microorganisms into the sand requiring reinforcement. These microorganisms combine with the nutrients they need and surrounding organic matter to generate bio-cement with good cementing properties. Compared to chemical grouting materials, it offers better durability and, while maintaining reinforcement strength, ensures the reinforced soil has a similar porosity to the original sand. Due to the low viscosity of the microbial solution, lower pressure is required during grouting, enabling large-scale, long-distance reinforcement of sand by microorganisms, while avoiding the disturbance to the soil caused by traditional grouting methods. Based on the known principles of microbial mineralization, the rate and intensity of calcium carbonate formation are controllable. Unlike cement reinforcement, microbial reinforcement requires no curing; furthermore, this technology can be directly applied to infrastructure requiring reinforcement, significantly shortening the reinforcement time. Microbial-induced calcium carbonate (MICP) technology is an emerging technology that has been developed in recent years. It has the characteristics of easy control of reaction rate, known principle, convenient operation, and environmental friendliness. Therefore, the use of microorganisms to induce calcium carbonate production has been applied to many disciplines and has begun to be used in geotechnical engineering, environmental engineering, and wastewater treatment.

[0003] However, existing MIP reinforcement technologies largely rely on traditional grouting equipment, which suffers from problems such as uneven grouting, inaccurate temperature and humidity control, and low efficiency due to multiple alternating grouting cycles. This leads to uneven distribution of calcium carbonate precipitation, affecting the reinforcement effect. In addition, the lack of integrated devices results in long construction cycles and high costs.

[0004] Therefore, a device for reinforcing cast-in-place pile foundations in sandy soil strata is proposed to address the aforementioned technical challenges. Utility Model Content

[0005] In order to solve the above-mentioned problems existing in the prior art, the present invention provides a device for reinforcing cast-in-place pile foundations in sandy soil strata.

[0006] The technical solution of this utility model is as follows:

[0007] A device for reinforcing cast-in-place pile foundations in sandy soil includes a grouting control system and an intelligent control system. The grouting control system includes a grouting pump installed on the ground surface and a grouting pipe buried underground. The top of the grouting pump is connected to a bacterial solution storage tank and a nutrient solution storage tank via a multi-channel switching valve. The grouting pump feeds grout into the grouting pipe through a connecting pipe equipped with a flow meter and a pressure sensor at the connection between the connecting pipe and the grouting pipe. The flow meter, grouting pump, and pressure sensor are all electrically connected to the intelligent control system. An insulation layer covers the ground surface around the grouting pipe opening, and the insulation layer is electrically connected to the intelligent control system.

[0008] Preferably, an atomizing nozzle is provided on the outer peripheral wall at the bottom end of the grouting pipe.

[0009] Preferably, the insulation layer includes a removable insulation film, and the bottom of the insulation film is provided with a built-in humidity sensor that is electrically connected to the intelligent control system.

[0010] Preferably, the grouting pipes are evenly distributed around the cast-in-place pile in a grid or quincunx pattern.

[0011] Preferably, the outer wall of the grouting pipe is surrounded by heating wires.

[0012] This invention has the following beneficial effects: It improves the side friction resistance between the pile foundation and the soil by using microbial induced calcium carbonate precipitation (MICP) technology. It strengthens the cast-in-place pile foundation in sandy soil by setting up a device that cooperates with the grouting control system and the intelligent control system. After storing bacterial solution and nutrient solution in the grouting control system, the grout is injected into the soil around the cast-in-place pile through the grouting pump monitored by the intelligent control system, thereby improving the side friction resistance between the pile foundation and the soil. Attached Figure Description

[0013] Figure 1 This is a flowchart of the overall device structure of this utility model;

[0014] Figure 2 This is a schematic diagram showing the location distribution of the grouting pipe and the cast-in-place pile of this utility model;

[0015] Figure 3 This is a top view schematic diagram showing the location distribution of the grouting pipe and the cast-in-place pile of this utility model.

[0016] The reference numerals in the figure are as follows:

[0017] 1. Bacterial solution storage tank; 2. Nutrient solution storage tank; 3. Multi-channel switching valve; 4. Grouting pump; 5. Grouting pipe; 6. Flow meter; 7. Pressure sensor; 8. Atomizing nozzle; 9. Insulation film; 10. Built-in humidity sensor; 11. Intelligent control system; 12. Cast-in-place pile. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0019] See Figures 1 to 3 A device for reinforcing cast-in-place pile foundations in sandy soil strata includes a grouting control system and an intelligent control system 11. The grouting control system includes a grouting pump 4 installed on the ground surface and a grouting pipe 5 buried in the ground. The top of the grouting pump 4 is connected to a bacterial solution storage tank 1 and a nutrient solution storage tank 2 respectively through a multi-channel switching valve 3. The grouting pump 4 inputs grout into the grouting pipe 5 through a connecting pipe. A flow meter 6 is installed on the connecting pipe, and a pressure sensor 7 is installed at the connection between the connecting pipe and the grouting pipe 5. The flow meter 6, the grouting pump 4, and the pressure sensor 7 are all electrically connected to the intelligent control system 11. An insulation layer is covered on the ground surface around the opening of the grouting pipe 5, and the insulation layer is electrically connected to the intelligent control system 11.

[0020] Furthermore, an atomizing nozzle 8 is provided on the outer peripheral wall of the bottom end of the grouting pipe 5.

[0021] Furthermore, the insulation layer includes a removable insulation film 9, and the bottom of the insulation film 9 is provided with a built-in humidity sensor 10 that is electrically connected to the intelligent control system.

[0022] Furthermore, the grouting pipes 5 are evenly distributed around the cast-in-place pile 12, arranged in a grid or quincunx pattern.

[0023] Furthermore, the outer wall of the grouting pipe 5 is surrounded by heating wires.

[0024] The working principle of this utility model:

[0025] In this invention, microbial induced calcium carbonate precipitation (MICP) technology is used to improve the side friction resistance between the pile foundation and the soil. The overall device includes a grouting control system and an intelligent control system 11. The grouting control system includes a grouting pump 4 installed on the ground surface and a grouting pipe 5 buried in the ground. The top of the grouting pump 4 is connected to the bacterial solution storage tank 1 and the nutrient solution storage tank 2 respectively through a multi-channel switching valve 3. The grouting pump 4 inputs grout into the grouting pipe 5 through a connecting pipe. A flow meter 6 is installed on the connecting pipe, and a pressure sensor 7 is installed at the connection between the connecting pipe and the grouting pipe 5. The flow meter 6, the grouting pump 4, and the pressure sensor 7 are all electrically connected to the intelligent control system 11.

[0026] Both the bacterial solution storage tank 2 and the nutrient solution storage tank 2 are equipped with a stirrer and a temperature control module to maintain the activity of the bacterial solution, and the temperature control module keeps the temperature between 4℃ and 10℃.

[0027] The grouting pump 5 is equipped with a variable frequency motor, with an adjustable grouting rate of 0.1-0.5 L / min and a pressure range of 0.1-0.5 MPa. It can perform multiple alternating grouting procedures by using a multi-channel switching valve 3.

[0028] In this utility model, the ground surface around the opening of the grouting pipe 5 is covered with a heat insulation layer. The heat insulation layer is electrically connected to the intelligent control system 11. The heat insulation layer includes a detachable heat insulation film 9. The bottom of the heat insulation film 9 is provided with a built-in humidity sensor 10 that is electrically connected to the intelligent control system. The grouting pipe 5 is evenly arranged around the grouting pile 12 in a grid or quincunx pattern.

[0029] The flow meter 6 and pressure sensor 7 are used to monitor grouting parameters in real time and feed them back to the intelligent control unit 11.

[0030] Meanwhile, atomizing nozzles 8 are provided on the outer peripheral wall at the bottom end of the grouting pipe 5. The atomizing nozzles 8 are evenly distributed and used to regulate humidity. The humidity regulation range is 70%-95%. In this embodiment, three layers of atomizing nozzles 8 can be set with a spacing control of 100mm. Four atomizing nozzles 8 are arranged in each layer to ensure humidity.

[0031] Furthermore, the outer wall of the grouting pipe 5 is surrounded by heating wires, with a temperature adjustment range of 20-40℃ and an accuracy of ±1℃.

[0032] The reinforcement steps are as follows:

[0033] 1. Drill holes in a quincunx pattern (0.8m spacing) to 2m below the bottom of pile 12, with a hole diameter of 5-10cm.

[0034] 2. Insert the grouting pipe 5 into the hole and connect the grouting pump 4.

[0035] 3. Set the grouting rate to 0.3 L / min and the pressure to 0.3 MPa. Activate the temperature control system in the bacterial solution storage tank 1 and the nutrient solution storage tank 2 to maintain a temperature of 30℃ and a humidity of 85%.

[0036] 4. Inject bacterial solution (OD600 = 1.2) and nutrient solution (urea + calcium chloride, concentration 0.75 mol / L) alternately in 3 to 4 rounds through a multi-channel switching valve, with an interval of 12 hours between each round;

[0037] 5. End grouting and cure for 48 hours.

[0038] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A device for reinforcing cast-in-place pile foundations in sandy soil strata, comprising a grouting control system and an intelligent control system (11), characterized in that: The grouting control system includes a grouting pump (4) installed on the ground surface and a grouting pipe (5) buried in the ground. The top of the grouting pump (4) is connected to the bacterial liquid storage tank (1) and the nutrient liquid storage tank (2) respectively through a multi-channel switching valve (3). The grouting pump (4) inputs the grout into the grouting pipe (5) through a connecting pipe. A flow meter (6) is installed on the connecting pipe, and a pressure sensor (7) is installed at the connection between the connecting pipe and the grouting pipe (5). The flow meter (6), the grouting pump (4) and the pressure sensor (7) are all electrically connected to the intelligent control system (11). The ground surface around the opening of the grouting pipe (5) is covered with a heat insulation layer, which is electrically connected to the intelligent control system (11).

2. The device for reinforcing cast-in-place pile foundations in sandy soil strata according to claim 1, characterized in that: The bottom outer peripheral wall of the grouting pipe (5) is provided with an atomizing nozzle (8).

3. The device for reinforcing cast-in-place pile foundations in sandy soil as described in claim 1, characterized in that: The insulation layer includes a removable insulation film (9), and the bottom of the insulation film (9) is provided with a built-in humidity sensor (10) that is electrically connected to the intelligent control system.

4. The device for reinforcing cast-in-place pile foundations in sandy soil strata according to claim 1, characterized in that: The grouting pipes (5) are evenly distributed around the cast-in-place pile (12) in a grid or plum blossom pattern.

5. The device for reinforcing cast-in-place pile foundations in sandy soil strata according to claim 1, characterized in that: The outer wall of the grouting pipe (5) is surrounded by heating wires.

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