Simulated atomization grouting device and method for soft stratum

Abstract

The invention belongs to the technical field of engineering simulation, and discloses a soft stratum simulation atomization grouting device and method. The device comprises a double-pressure supply device, a slurry storage barrel, an atomizer comprising an atomizing bin and an ultrasonic atomizing sheet, a nozzle, a pressure monitor, a test piece box and a slurry recycling barrel, and all the parts are connected with valves through pipelines to form a complete grouting system. According to the method, slurry is atomized, pressure is regulated and controlled in combination with a double-pressure-supply device, pressure changes are captured in real time in cooperation with a pressure monitor, and slurry diffusion leading edge information is dynamically mastered. According to the method, the technical problems that in the prior art, the adaptability of grout and an unconsolidated stratum is poor, the grouting pressure control precision is low, and effective real-time monitoring is lacked are effectively solved, the permeability and diffusion uniformity of the grout in the stratum are greatly improved, stratum disturbance or structural damage caused by out-of-control grouting is avoided, and the grouting quality is improved. Accurate parameter support is provided for site construction through an indoor simulation experiment, the trial and error cost is remarkably reduced, and the reliability and engineering practicability of grouting reinforcement of the soft stratum are improved.

Description

Technical Field

[0001] This invention belongs to the field of engineering simulation technology, and in particular relates to a device and method for simulating atomized grouting in soft strata. Background Technology

[0002] In the current field of underground engineering, chemical grouting for soft strata (such as silty clay and alluvial sand layers) still faces many technical challenges. Existing grouting processes, such as Chinese patent CN220927862U (a high-pressure jet grouting device for roadbed engineering), have the following three key defects: First, the grout system is not well-suited to loose strata. Currently used polymer grouting materials generally have critical permeable pore sizes greater than 20 μm, making it difficult to effectively penetrate strata with micron-sized pore structures such as fine sand layers, thus limiting the effective filling and consolidation effects of the grout. Second, the grouting pressure control accuracy is low, typically with an error range of ±0.5 MPa, making it difficult to precisely control the grout diffusion behavior. This pressure fluctuation easily causes the grout diffusion pattern to deviate from the ideal columnar permeability model. For example, in water-rich sandstone strata, when the grouting pressure exceeds a critical value (such as 0.8 MPa), the grout diffusion radius will exhibit an exponential growth trend, leading to unexpected strata disturbances or structural damage. Third, the lack of effective real-time monitoring methods makes it impossible to dynamically grasp the diffusion front information of grout in the strata. Such information deficiency may lead to loss of control in the grouting process. For example, in a tunnel project, the grouting operation was terminated because the grout diffusion boundary was not determined in time, which ultimately resulted in excessive segment misalignment (>5mm), affecting structural safety and construction quality.

[0003] Therefore, there is an urgent need to develop a chemical grouting test device suitable for soft strata in order to obtain dynamic information on the grout diffusion front. Summary of the Invention

[0004] The purpose of this invention is to provide a simulated atomized grouting device for soft formations, which enables high-precision observation of grouting in soft formations by atomizing the grout, thereby obtaining dynamic information on the grout diffusion front; and to provide guidance for solving problems such as poor compatibility between process grout and loose formations and inaccurate control of grouting pressure.

[0005] The second objective of this invention is to provide a method for simulating atomized grouting in soft formations.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is a soft stratum simulated atomized grouting device, including a grout storage tank; the grout storage tank is connected to an atomizing device through a pipeline, the atomizing device includes an atomizing chamber and an atomizer assembled in the atomizing chamber, the atomizing chamber is connected to a nozzle through a pipeline, and the nozzle extends into the specimen chamber; a first pressure pump is connected to the atomizing chamber through a pipeline, and a second pressure pump is connected to the grout storage tank through a pipeline; valves and pressure monitoring instruments are correspondingly assembled on the pipelines, and a grout recovery tank is connected to the atomizing chamber and the grout storage tank through pipelines respectively.

[0007] Furthermore, the atomizer includes an ultrasonic atomizing plate, a power supply device, and an atomization switch. The power supply device is electrically connected to the ultrasonic atomizing plate, and the atomization switch is used to control the power supply to and from the ultrasonic atomizing plate.

[0008] Furthermore, a pressure monitoring instrument is installed on the pipe between the atomizing chamber and the nozzle, and a valve is provided on the pipe section between the pressure monitoring instrument and the atomizing chamber; a pressure monitoring instrument is installed on the pipe between the atomizing device and the first pressure pump; and a pressure monitoring instrument is provided on the pipe between the slurry storage tank and the second pressure pump.

[0009] Furthermore, the bottom of the slurry storage tank is provided with a pipe extending to the slurry recovery tank, and a valve is provided on the pipe.

[0010] Furthermore, the ultrasonic atomizing plate is assembled at the interface between the end of the pipe and the atomizing chamber.

[0011] Furthermore, the inner diameter of the pipe is selected to be 25-32mm, and the length of the pipe connected to the test specimen box does not exceed 2m.

[0012] A method for simulating atomized grouting in soft formations, implemented using the aforementioned simulating atomized grouting device for soft formations, includes the following steps:

[0013] S1. Perform material preparation operations and complete the assembly and debugging of each device; wherein, the materials include the prepared grouting slurry;

[0014] S2. Start the atomizing device and simultaneously open the valve of the corresponding pipe between the slurry recovery tank and the atomizing chamber to make the atomized slurry in the atomizing chamber saturate.

[0015] S3. Start the first pressure pump to fill the atomizing chamber with atomized slurry;

[0016] S4. After the slurry flows into the slurry recovery tank, close the valve of the corresponding pipeline of the slurry recovery tank, and then start the second pressure pump to observe the slurry flow status and the grouting molding effect of the test block in real time. When the system pressure is detected to rise sharply, it indicates that the slurry has effectively filled the injected soil. Open the valve of the pipeline between the slurry recovery tank and the atomization chamber.

[0017] S5. Turn off the atomizer and simultaneously close the valve on the pipe above the nozzle;

[0018] S6. Move the pipe above the nozzle upwards by a preset distance and repeat the grouting-related operations from S2 to S6 above; until the entire grouting area is grouted, proceed with the next steps.

[0019] S7. Open the valve between the slurry recovery tank and the slurry storage tank. After the slurry has completely flowed into the slurry recovery tank, close all corresponding switches and valves of the device.

[0020] S8. Shut down all equipment, clean the grouting pipes and other related equipment, then open the specimen box and take out the specimen to be grouted.

[0021] Furthermore, the grout prepared in step S1 is an acrylate or epoxy resin low-viscosity grouting material; wherein, the epoxy resin to curing agent mixing ratio of the epoxy resin grout is 8:1 to 10:1, and the specific ratio can be adjusted according to the actual experimental results; and the viscosity of the grout after necessary heating pretreatment is ≤100cp.

[0022] Furthermore, the pressure control requirements for the first pressure pump 1 and the second pressure pump 2 are as follows: the initial grouting pressure is controlled at the level of 0.01 MPa, and the pressure is adjusted by gradually increasing the pressure thereafter; according to the density of the simulated strata and the differences in the characteristics of the grouting material, the maximum grouting pressure is controlled within the range of 0.05 MPa to 0.1 MPa; for simulated strata with particularly soft texture, the maximum grouting pressure shall not exceed 0.05 MPa; a high-precision pressure sensor with an accuracy of ±0.001 MPa is used to monitor the grouting pressure in real time to ensure that the pressure is within the set range.

[0023] Furthermore, during the grouting process, the pressure monitoring instrument values ​​are observed in real time to determine the grouting status: if the pressure drops suddenly, it indicates that the grout has opened a penetration channel, diffused to the preset diffusion boundary, or encountered a large cavity area; if the pressure continues to rise, it indicates that the formation is highly compact, the grout penetration is difficult, or there is a risk of blockage in the pipes or nozzles.

[0024] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention atomizes the slurry into tiny droplets using an ultrasonic atomizing device, significantly improving the slurry's permeability and diffusion uniformity in the formation. It successfully solves the technical problem of traditional slurries being difficult to adapt to micron-sized porous formations such as fine sand layers, ensuring that soft formations can be fully filled and consolidated. Relying on the synergistic design of a dual-pressure supply device and a high-precision pressure monitoring instrument, the pressure difference between the two ends of the ultrasonic atomizing plate is effectively balanced, ensuring the stable operation of the atomization system. Simultaneously, precise control of the grouting pressure is achieved, avoiding problems such as abnormal slurry diffusion patterns, formation disturbance, or structural damage caused by pressure fluctuations in traditional processes. Through pressure monitoring... The instrument captures pressure changes in real time during the grouting process, dynamically monitors the grout diffusion front information, and promptly predicts conditions such as the opening of seepage channels, the arrival of diffusion boundaries, or the risk of blockage. This fundamentally eliminates the phenomenon of uncontrolled grouting and ensures construction quality and structural safety. In addition, the device has a complete grout recovery function, which can efficiently recover residual grout and condensed grout in the grout storage tank and atomization chamber, saving grouting materials and reducing waste. Furthermore, through indoor simulation experiments, it can systematically verify the compatibility of different strata and different grouts, providing precise parameter support for on-site construction, significantly reducing the trial and error costs of traditional experience-based construction, and improving the practicality and reliability of grouting reinforcement in soft strata. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of a simulated atomized grout injection device.

[0027] Figure 2 This is a schematic diagram of the atomizing device structure;

[0028] Figure 3 This is a graph showing the atomization efficiency versus liquid viscosity.

[0029] In the diagram, 1. First pressure pump; 2. Second pressure pump; 3. Slurry storage tank; 4. Atomization chamber; 5. Slurry recovery tank; 6. Specimen box; 7. Atomizer; 8. Nozzle; 9. Pressure monitoring instrument; 10. Pipeline; 11. Valve; 12. Atomizing plate; 13. Power supply device; 14. Atomization switch. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] like Figure 1 This embodiment provides a simulated atomized grouting device and method for soft strata. The grouting device is specifically an atomized grouting device for soft strata, which mainly includes a first pressure supply device, a second pressure supply device, an atomizing device, and a grout recovery tank 5.

[0032] In some specific embodiments, the atomizing device includes an atomizer 7 and an atomizing chamber 4, with the atomizer 7 mounted on the top of the atomizing chamber 4. The atomizing device also includes a nozzle 8, which is connected to the side wall of the atomizing chamber 4 via a pipe 10, and extends into the soft soil layer. Specifically, a pressure monitoring instrument 9 is mounted on the connecting pipe 10 between the nozzle 8 and the atomizing chamber 4, and a valve 11 is installed on the section of pipe 10 between the pressure monitoring instrument 9 and the atomizing chamber 4. The functions of the pressure monitoring instrument 9 include: preventing system pressure overload, balancing the pressure of the atomizing plate 12 to ensure the stability of the atomization process; and providing real-time feedback on the grouting condition to achieve accurate judgment of the grouting status.

[0033] In some specific embodiments, the first pressure supply device includes a first pressure pump 1. The output end of the first pressure pump 1 is connected to the top of the atomizing chamber 4 of the atomizing device via a connecting pipe. A connecting pipe 10 is provided on the side wall at the bottom of the atomizing chamber 4, and the connecting pipe 10 is connected to the slurry recovery tank 5. During the grouting process, the first pressure pump 1 provides the driving force and pressure required for grouting, and transports the atomized slurry in the atomizing storage tank 3 to and injects it into the grouting device. After the grouting process is completed, the first pressure pump 1 continues to output pressure, and transports the remaining atomized slurry in the atomizing storage tank 3 and the liquefied slurry formed after coagulation to and recovers it into the slurry recovery tank 5 via the connecting pipe.

[0034] A pressure monitoring instrument 9 is installed on the pipeline 10 between the atomizing device and the first pressure pump 1; a valve 11 is installed on the pipeline 10 between the atomizing device and the slurry recovery tank 5.

[0035] The second pressure supply device includes a second pressure pump 2, the output end of which is connected to the slurry recovery tank 5 via a connecting pipe. During the grouting process, the second pressure pump 2 provides the required delivery pressure to transport the slurry in the storage tank 3 to the atomizing device, while balancing the air pressure at both ends of the atomizing device to ensure its stable and normal operation. After the grouting process is completed, the second pressure pump 2 continues to output pressure to transport the remaining slurry in the storage tank 3 to and recover it into the slurry recovery tank 5 via the connecting pipe.

[0036] In some specific embodiments, the top of the slurry storage tank 3 is connected to the second pressure pump 2 via a connecting pipe, and a pressure monitoring instrument 9 is installed on the connecting pipe 10; the side wall of the bottom of the slurry storage tank 3 is connected to the atomizer 7 of the atomizing device via a pipe 10, and a valve 11 is installed on the connecting pipe 10. During the grouting process, the pressure generated by the second pressure pump 2 is transmitted to the inside of the slurry storage tank 3 via the connecting pipe 10, causing the slurry in the slurry storage tank 3 to enter the atomizing device sequentially through the pipe 10 and the valve 11 under pressure; the bottom of the slurry storage tank 3 is also provided with a connecting pipe 10, which extends to the top of the slurry recovery tank 5, and a valve 11 is installed on the pipe 10; after the grouting process is completed, under pressure, the remaining slurry in the slurry storage tank 3 is continuously transported along the connecting pipe 10 and finally flows into the slurry recovery tank 5.

[0037] like Figure 2 As shown, the atomizer 7 includes an ultrasonic atomizing plate 12, a power supply device 13, and an atomization switch 14. The power supply device 13 provides the energy required for the ultrasonic atomizing plate 12 to operate. In this embodiment, the power supply device 13 uses a battery, but other devices capable of meeting the energy supply requirements of the ultrasonic atomizing plate 12 can also be selected according to actual application needs. The ultrasonic atomizing plate 12 is assembled at the interface between the end of the pipe 10 and the atomization chamber 4 to achieve immediate atomization of the slurry entering through the pipe 10. The atomization switch 14 controls the power supply from the power supply device 13 to the ultrasonic atomizing plate 12, thereby controlling the start and stop of the atomization process. After the atomizing switch 14 is turned on, the ultrasonic atomizing plate 12 atomizes the liquid slurry in the pipe 10, and the atomized slurry enters the atomizing chamber 4. During the entire grouting process, the pressure generated by the first pressure pump 1 is transmitted to the atomizing chamber 4 through the connecting pipe 10. Under the action of this pressure, the atomized slurry is injected into the soft stratum through the pipe 10 and the nozzle 8. After the grouting process is completed, the liquid slurry formed at the bottom of the atomizing chamber 4 and the remaining atomized slurry are collected into the slurry recovery tank 5 through the connecting pipe 10 under the action of pressure.

[0038] In some optional embodiments, to ensure the atomization effect of this embodiment, the diameter of the pipe 10 is selected to be 25-32mm, and the length of the pipe 10 connected to the test specimen box 6 does not exceed 2m. It should be noted that if the length of the pipe 10 connected to the test specimen box 6 is too long, it will cause the grout to solidify inside the pipe 10, thereby affecting the normal operation of the grouting and atomization system.

[0039] In some specific embodiments, this embodiment also provides a simulated atomized grouting device and method for soft strata, the specific implementation process of which includes the following steps: S1. Perform material preparation operations and complete the assembly and debugging of each device; wherein, the materials include prepared slurry with a viscosity ≤100cp.

[0040] S2. Start the atomizing device and simultaneously open the valve 11 of the pipe 10 corresponding to the slurry recovery tank 5 and the atomizing chamber 4 to saturate the atomized slurry in the atomizing chamber 4. The slurry has a higher flow rate in the pipe and is less prone to condensation, but the flow rate in the atomizing chamber 4 is lower and condensation may occur. Opening the valve 11 of the pipe 10 corresponding to the slurry recovery tank 5 ensures that the atomized slurry has a relatively stable concentration, so the concentration of the atomized slurry in the atomizing chamber 4 is first brought to saturation.

[0041] S3. Start the first pressure supply device to fill the atomizing chamber 4 with atomized slurry.

[0042] S4. After the slurry flows into the slurry recovery tank 5, it indicates that the atomized slurry in the atomization chamber 4 has reached saturation. S5. Close valve 11 of pipe 10 corresponding to slurry recovery tank 5, then start the second pressure supply device and observe the slurry flow status and grouting effect of the test block in real time. When the system pressure is detected to rise significantly, it indicates that the slurry has effectively filled the injected soil. Open valve 11 of pipe 10 between slurry recovery tank 5 and atomizing device.

[0043] S6. Turn off the atomizer 7 and at the same time close the valve 11 of the pipe 10 above the nozzle 8.

[0044] S7. Move the pipe 10 above the nozzle 8 upwards by a preset distance and repeat the grouting-related operations from S2 to S6; until the entire grouting area is grouted, proceed with the next steps.

[0045] S8. Open the valve between the slurry recovery tank 5 and the slurry storage tank 3; after the slurry has completely flowed into the slurry recovery tank 5, close all corresponding switches and valves 11.

[0046] S9. Shut down all equipment, clean the grouting pipes and other related equipment, then open specimen box 6 and take out the grouting sample. The specific experimental test procedure is as follows: First, grouting is carried out in the simulated stratum. After the grout has completely solidified to form a "stone body", the stone body is carefully excavated from the loose sand and completely removed. Next, the diffusion range of the stone body is measured and its morphology is observed to evaluate the permeability and consolidation effect of the grout. Then, the compressive strength test is carried out by core drilling to quantify the mechanical performance indicators of the stone body. Finally, the experimental data such as grouting pressure, grout diffusion distance and stone body strength are comprehensively analyzed to reveal the inherent correlation between the parameters, thereby verifying the reinforcement efficiency of the device and method in soft strata.

[0047] During the grouting process, the changes in the pressure monitoring instrument 9 need to be observed in real time. The monitoring and judgment logic is as follows: if the pressure monitoring instrument 9 shows a sudden drop in pressure, it indicates that the grout has opened a penetration channel, or diffused to the preset diffusion boundary, or encountered a large cavity area; if the pressure monitoring instrument 9 shows a continuous increase in pressure, it indicates that the formation is highly compact, the grout penetration is difficult, or there is a risk of blockage in the pipe 10 or nozzle 8.

[0048] In some optional embodiments, the selection and compatibility requirements for grouting materials are as follows: This embodiment is applicable to low-viscosity grouting materials such as acrylate and epoxy resin grouts; for epoxy resin grouts, the mixing ratio (mass ratio) of epoxy resin and curing agent can be selected in the range of 8:1 to 10:1, and the specific ratio needs to be adjusted adaptively according to the actual experimental results. If the atomization effect is poor during the grouting process, the grout needs to be pre-treated by heating to reduce the grout viscosity to below 100 cp to ensure the smooth implementation of the atomization process.

[0049] In some optional implementations, the core technical parameters of the ultrasonic atomizing plate 12 are set as follows: the working frequency is 2.4MHz and the diameter is selected as 30-50mm.

[0050] The pressure control requirements for the pressure supply device (including the first pressure pump 1 and the second pressure pump 2) are as follows: the initial grouting pressure is controlled at the level of 0.01 MPa, and the pressure is subsequently adjusted by gradually increasing the pressure to ensure that the grout flows smoothly and penetrates fully in the shallow simulated formation. Depending on the density of the simulated formation and the characteristics of the grouting material, the maximum grouting pressure needs to be controlled within the range of 0.05 MPa to 0.1 MPa; for particularly soft simulated formations, the maximum grouting pressure must not exceed 0.05 MPa. To ensure that the grouting pressure is strictly within the above-mentioned set range, a high-precision pressure sensor with an accuracy of ±0.001 MPa is used for real-time monitoring of the grouting pressure.

[0051] Furthermore, the soft stratum sample in specimen box 6 in this embodiment is reconstructed in the laboratory using standardized geotechnical materials at a corresponding scale, based on the geological survey report of the target engineering site (including key parameters such as particle size distribution curve, porosity, water content, and mineral composition). This reconstruction method ensures that the key physical parameters of the experimental medium are on the same order of magnitude as the on-site stratum parameters. For strata with stratification, fissures, or weak interlayers, a similar structural model can be artificially laid in specimen box 6 to study the diffusion path and sealing effect of the grout in different stratum structures.

[0052] This implementation method, through precise control of the first pressure pump 1 and the second pressure pump 2, can construct a pressure gradient within a small-scale model that is similar to the actual working conditions and can effectively drive the grout seepage. This allows for the reproduction of the physical mechanism of grout flow, penetration, and filling in porous media. With the assistance of a transparent laboratory model, the one-to-one correspondence between grouting pressure changes and grout diffusion behavior (such as diffusion to the boundary, splitting, etc.) can be observed directly, thereby providing technical guidance for on-site construction.

[0053] This implementation method can be used to guide the selection of on-site construction parameters, minimizing the cost of on-site trial and error. The core value of this invention is not to replace on-site testing, but to move the traditionally experience-dependent and high-risk on-site trial and error process forward to a low-cost, high-efficiency, and highly deterministic laboratory.

[0054] Currently, the engineering application of atomized grouting technology is limited, and relevant engineering experience is scarce. Engineers can only set a wide range of parameters based on traditional grouting experience, which easily leads to problems such as parameters exceeding or falling short of standards during the process. However, by conducting indoor experiments in advance using this device, the optimal pressure range with a narrower range can be determined, providing precise parameter support for on-site construction.

[0055] One of the core functions of this implementation method is to conduct systematic batch experiments. In the laboratory, various standard model soil samples that can characterize different types of soft strata can be prepared; for each type of strata, the atomization and penetration effects of different slurries (including different chemical types, different viscosities, and different ratios) can be tested.

[0056] Before the actual project is implemented, a detailed geological survey must be carried out to obtain key geological parameters (such as porosity, permeability coefficient, etc.); the on-site geological parameters are compared and matched with standard model soil samples, and the model soil sample that is most similar to the on-site geological properties is selected. Based on this, one or more experimentally verified grout selection schemes and parameter ranges with a high success rate are provided for on-site construction.

[0057] In this embodiment, while the pressure monitoring instrument 9 records the pressure-time curve, the camera simultaneously records the real-time position of the slurry diffusion front within the specimen chamber 6. By synchronously correlating the two sets of data on the time axis, a one-to-one correspondence between pressure change characteristics and events within the formation can be established. The specific correspondence logic is as follows: a steady increase in pressure corresponds to uniform slurry permeation in the pores; a sudden and sharp increase in pressure corresponds to the slurry encountering permeation resistance or about to undergo hydraulic fracturing; a sudden drop in pressure corresponds to the slurry diffusion front reaching the model boundary or entering large fractures or cavities.

[0058] In some specific embodiments, several slurries are first prepared and their viscosity is measured. A beaker is placed below the outlet of pipe 10 connected to the specimen box, the prepared slurries are added, and the weight of each experimental device (including the beaker) is measured. With pipe 10 being 1 meter long and the atomizing plate operating at a frequency of 2.4 MHz, the device is started. After 10 minutes, the weight of each experimental device is measured again. The decrease in the sum of the weights of all devices is the weight of the atomized slurry. The total weight reduction of the three experimental devices (slurry storage tank 3, atomizing chamber 4, and slurry recovery tank 5) is the weight of the consumed slurry. The ratio of the weight of the atomized slurry to the weight of the consumed slurry is the atomization efficiency, thus obtaining the following... Figure 3 The relationship between liquid viscosity and atomization efficiency.

[0059] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A soft stratum simulated atomized grouting device, characterized in that, The system includes a slurry storage tank (3); the slurry storage tank (3) is connected to an atomizing device via a pipe (10); the atomizing device includes an atomizing chamber (4) and an atomizer (7) assembled in the atomizing chamber (4); the atomizing chamber (4) is connected to a nozzle (8) via a pipe (10); the nozzle (8) extends into the specimen box (6); a first pressure pump (1) is connected to the atomizing chamber (4) via a pipe (10); a second pressure pump (2) is connected to the slurry storage tank (3) via a pipe (10); a valve (11) and a pressure monitoring instrument (9) are correspondingly assembled on the pipe (10); and a slurry recovery tank (5) is connected to the atomizing chamber (4) and the slurry storage tank (3) via a pipe (10).

2. The soft stratum simulated atomized grouting device according to claim 1, characterized in that, The atomizer (7) includes an ultrasonic atomizing plate (12), a power supply device (13) and an atomization switch (14). The power supply device (13) is electrically connected to the ultrasonic atomizing plate (12), and the atomization switch (14) is used to control the power supply to the power supply device (13) and the ultrasonic atomizing plate (12).

3. The soft stratum simulated atomized grouting device according to claim 1, characterized in that, A pressure monitoring instrument (9) is installed on the pipe (10) between the atomizing chamber (4) and the nozzle (8), and a valve (11) is provided on the section of the pipe (10) between the pressure monitoring instrument (9) and the atomizing chamber (4); a pressure monitoring instrument (9) is installed on the pipe (10) between the atomizing device and the first pressure pump (1); a pressure monitoring instrument (9) is provided on the pipe (10) between the slurry storage tank (3) and the second pressure pump (2).

4. The soft stratum simulated atomized grouting device according to claim 1, characterized in that, The bottom of the slurry storage tank (3) is provided with a pipe (10) extending to the slurry recovery tank (5), and a valve (11) is provided on the pipe (10).

5. The soft stratum simulated atomized grouting device according to claim 2, characterized in that, The ultrasonic atomizing plate (12) is assembled at the interface between the end of the pipe (10) and the atomizing chamber (4).

6. The soft stratum simulated atomized grouting device according to claim 1, characterized in that, The inner diameter of the pipe (10) is selected to be 25-32mm, and the length of the pipe (10) connected to the test specimen box (6) does not exceed 2m.

7. A method for simulating atomized grouting in soft formations, characterized in that, The soft strata simulated atomized grouting device according to any one of claims 1-6 is implemented, including the following steps: S1. Perform material preparation operations and complete the assembly and debugging of each device; wherein, the materials include the prepared grouting slurry; S2. Start the atomizing device and simultaneously open the valve (11) of the corresponding pipe (10) between the slurry recovery tank (5) and the atomizing chamber (4) to make the atomized slurry in the atomizing chamber (4) saturate. S3. Start the first pressure pump (1) to fill the atomizing chamber (4) with atomized slurry. S4. After the slurry flows into the slurry recovery tank (5), close the valve (11) of the pipe (10) corresponding to the slurry recovery tank (5), and then start the second pressure pump (2) to observe the slurry flow status and the grouting effect of the test block in real time. When the system pressure is detected to rise significantly, it indicates that the slurry has effectively filled the soil to be injected. Open the valve (11) of the pipe (10) between the slurry recovery tank (5) and the atomization chamber (4). S5. Turn off the atomizer (7) and at the same time close the valve (11) of the pipe (10) above the nozzle (8). S6. Move the pipe (10) above the nozzle (8) upward by a preset distance and repeat the grouting-related operations from S2 to S6; until the entire grouting area is grouted, proceed with the next steps. S7. Open the valve (11) between the slurry recovery tank (5) and the slurry storage tank (3). After the slurry has completely flowed into the slurry recovery tank (5), close all the corresponding switches and valves (11). S8. Shut down all equipment, clean the grouting pipe and other related equipment, and then open the specimen box (6) to take out the specimen to be grouted.

8. The method for simulating atomized grouting in soft formations according to claim 7, characterized in that, The grout prepared in step S1 is an acrylate or epoxy resin low-viscosity grouting material; wherein, the epoxy resin to curing agent mixing ratio of the epoxy resin grout is 8:1 to 10:1, and the specific ratio can be adjusted according to the actual experimental results; and the viscosity of the grout after necessary heating pretreatment is ≤100cp.

9. The method for simulating atomized grouting in soft formations according to claim 7, characterized in that, The pressure control requirements for the first pressure pump (1) and the second pressure pump (2) are as follows: the initial grouting pressure is controlled at the level of 0.01 MPa, and the pressure is adjusted by gradually increasing the pressure thereafter; the maximum grouting pressure is controlled within the range of 0.05 MPa to 0.1 MPa according to the density of the simulated strata and the differences in the characteristics of the grouting materials; for simulated strata with particularly soft texture, the maximum grouting pressure shall not exceed 0.05 MPa; a high-precision pressure sensor with an accuracy of ±0.001 MPa is used to monitor the grouting pressure in real time to ensure that the pressure is within the set range.

10. The method for simulating atomized grouting in soft formations according to claim 7, characterized in that, During the grouting process, the pressure monitoring instrument (9) is monitored in real time to determine the grouting status: if the pressure drops suddenly, it indicates that the grout has opened a penetration channel, diffused to the preset diffusion boundary or encountered a large cavity area; if the pressure continues to rise, it indicates that the stratum is dense and the grout penetration is difficult, or there is a risk of blockage in the pipe (10) or nozzle (8).

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