A curing agent slurry preparation device, a curing agent slurry preparation method, and a fluidized solidified soil production method

Abstract

This invention discloses a curing agent slurry preparation device, a curing agent slurry preparation method, and a fluidized solidified soil production method. In the preparation method, a weight sensor collects the weight change curve in real time during auger feeding, identifies the excess material discharge, and calculates the correction value for the next batch's shutdown advance. Water is injected and preliminary mixing is performed. The slurry is injected into the lower mixing chamber. After adjustment according to the correction value, the next batch is prepared. During the lower mixing, the torque of the second agitator is collected, a rheological curve is fitted, and the homogeneity is determined to be up to standard after the torque fluctuation rate is below a threshold and maintained for a set time, at which point the material is discharged. The upper and lower layers operate alternately in parallel cycles. The fluidized solidified soil production method of this invention includes: excavating a mud pit nearby and mixing it into mud; preparing the curing agent slurry using the above method; and pumping the slurry to the mud pit and mixing it into fluidized solidified soil. This invention employs a "two-step" process to prepare the curing agent and fluidized solidified soil in stages, avoiding long-distance transportation of the finished solidified soil and improving construction efficiency and the stability of the solidified soil quality.

Description

Technical Field

[0001] This invention belongs to the field of fluidized solidified soil production, specifically relating to a solidifying agent slurry preparation device, a solidifying agent slurry preparation method, and a fluidized solidified soil production method. Background Technology

[0002] Currently, the production of fluidized bed concrete commonly employs either plant mixing or road mixing methods, both of which are "one-step" processes, meaning all raw materials are mixed and stirred at once to prepare the finished fluidized bed concrete product. Plant mixing utilizes a mixing plant to centrally mix the fluidized bed concrete outside the construction site, and then transports it to the construction site using specialized vehicles such as concrete mixer trucks and slurry trucks for pouring. This method involves high investment in mixing plants and requires a large site area, often necessitating the leasing of existing concrete mixing plants near the project site. However, using existing concrete mixing plants requires both adaptation to the characteristics of the solidified soil and consideration of long-distance road transportation costs and scheduling outside the construction site. The entire production process of plant mixing involves significant investment, numerous procedures, and low efficiency. The road mixing method is equivalent to simplifying the concrete mixing plant and setting it up on the construction site, eliminating the need for road transportation outside the construction site. However, this method still involves uniformly mixing various raw materials to prepare a fluidized solidified soil product and transporting it to the construction site by vehicle for pouring. For large construction areas, large-scale transportation is required, and for narrow construction sites, where transport vehicles cannot enter, additional manual transfer is required.

[0003] In addition, fluidized solidified soil will gradually lose its fluidity and eventually harden over time. Therefore, both plant mixing and road mixing methods have high requirements for the scheduling of transport vehicles. Otherwise, if the delay is too long, it will inevitably affect the construction quality.

[0004] While there have been attempts to pre-form solid curing agents into slurries using a slurry-based process in the on-site mixing and preparation of non-fluidized solidified soil, existing slurry preparation equipment mostly employs single-layer mixing chambers for intermittent production, with batching and mixing carried out in separate steps, resulting in low efficiency and difficulty in ensuring slurry homogeneity. Solid raw material feeding relies on auger conveying, and the overfeeding caused by start-stop inertia is difficult to eliminate, leading to insufficient batching accuracy and stability. Slurry homogeneity determination mostly relies on manual sampling and testing or fixed-duration mixing, making it impossible to achieve real-time quality monitoring and adaptive discharge control. Summary of the Invention

[0005] Objectives of the Invention: The first objective of this invention is to provide a curing agent slurry preparation device that solves the technical problem that existing slurry preparation devices mostly adopt single-layer mixing chambers for intermittent production, with batching and mixing carried out in separate steps, resulting in low efficiency and difficulty in ensuring slurry homogeneity. The second objective of this invention is to provide a curing agent slurry preparation method that solves the problem in the prior art where the feeding of solid raw materials relies on auger conveying, leading to the difficulty in eliminating overfeeding caused by start-stop inertia. This method also solves the problem that the determination of slurry homogeneity mostly relies on manual sampling and testing or fixed-duration mixing, resulting in the inability to achieve real-time quality monitoring and adaptive discharge control. The third objective of this invention is to provide a method for producing fluidized solidified soil that avoids the loss of fluidity caused by long-distance transportation of fluidized solidified soil and prevents the fluidized solidified soil from hardening.

[0006] Technical Solution: The present invention provides a curing agent slurry preparation device, comprising a raw material storage tank, an upper mixing chamber, a lower mixing chamber, an automatic control cabinet, and a water tank. The raw material storage tank is connected to the upper mixing chamber via an auger. The upper mixing chamber is equipped with a first agitator and a first valve on its bottom wall, which is connected to the lower mixing chamber via a pipe. A weight sensor is installed below the upper mixing chamber to collect the weight of the upper mixing chamber in real time. A second agitator is installed in the lower mixing chamber, and a torque sensor is fixedly installed on the drive shaft end of the second agitator. A second valve is installed on the bottom wall of the lower mixing chamber, which is connected to the curing agent slurry preparation tank via a pipe. A water level sensor is installed on the inner side wall of the water tank, and a flow meter is installed on the water outlet pipe of the water tank, which is connected to the upper mixing chamber. The auger, the first agitator, the first valve, the weight sensor, the second agitator, the torque sensor, the second valve, the water level sensor, and the flow meter are all electrically connected to the automatic control cabinet.

[0007] Furthermore, the first agitator adopts a paddle-type structure, and the drive motor of the first agitator is electrically connected to the automatic control cabinet. The automatic control cabinet adjusts the agitation speed of the first agitator according to a preset program.

[0008] Furthermore, the second agitator adopts a double-layer blade structure, with the upper and lower blades arranged alternately.

[0009] Based on the same inventive concept, the present invention provides a method for preparing a curing agent slurry, applied to the above-mentioned curing agent slurry preparation apparatus, comprising the following steps:

[0010] S1. Start the automatic control program preset in the automatic control cabinet, and fill the water tank to the full water level;

[0011] S2. The automatic control cabinet controls the auger to feed the curing agent raw material from the raw material storage tank into the upper mixing chamber according to the preset formula. The weight sensor collects the weight change data of the upper mixing chamber in real time, generates a weight change curve and transmits it to the automatic control cabinet. The automatic control cabinet calculates the over-drop amount of raw material in this tray according to the weight change curve, and uses the over-drop amount to calculate the correction value of the auger shutdown advance for the next tray.

[0012] S3. When the weight sensor detects the completion signal of feeding, the water tank injects water into the upper mixing chamber, the flow meter measures the amount of water injected into the upper mixing chamber, and the first agitator is started at the same time as water injection to carry out preliminary mixing, so that the curing agent raw material and water can fully contact and mix to form a preliminary slurry.

[0013] S4. After water injection is completed, the first agitator continues to agitate for the preset time, and the automatic control cabinet controls the first valve to open, and the initial slurry is injected into the lower mixing chamber.

[0014] S5. After the upper mixing chamber is emptied, the automatic control cabinet controls the first valve to close and controls the first agitator to stop mixing. The automatic control cabinet adjusts the auger stop time according to the correction value and then repeats S2 to S4 to prepare the next batch of ingredients.

[0015] S6. Start the second agitator in the lower mixing chamber. The torque sensor collects the torque data of the second agitator in real time during the mixing process and transmits the torque data to the automatic control cabinet. The automatic control cabinet generates a torque change curve based on the torque data, and then fits the rheological curve of the slurry. Based on the rheological curve, it determines whether the torque fluctuation rate is lower than the preset dynamic threshold. When the torque fluctuation rate is lower than the preset dynamic threshold and is maintained for a set time, the homogeneity is determined to meet the standard.

[0016] S7. After the homogeneity meets the standard, the automatic control cabinet opens the second valve and starts the delivery pump on the pipeline to pump the fully mixed slurry to the curing agent slurry tank. After the lower mixing chamber is emptied, the second valve closes. At the same time, the upper mixing chamber has completed the next batch of preliminary mixing and is ready to be injected into the lower mixing chamber. S5 to S7 are executed in a cycle.

[0017] Furthermore, the automatic control cabinet calculates the excess material discharge amount of the current tray based on the weight change curve, and uses the excess material discharge amount to calculate the correction value for the lead time of the next tray auger shutdown, including:

[0018] The automatic control cabinet performs differential calculations on the weight change curve, identifies the abrupt change point in the feeding rate, and calculates the difference between the steady-state weight after the abrupt change point and the preset target weight to obtain the overfeed amount of the raw material in this tray.

[0019] The automatic control cabinet uses an iterative learning algorithm to calculate the weighted average of the overfeed amount of the three most recent batches of raw materials, and then obtains the correction value for the lead time of the auger shutdown in the next batch.

[0020] Furthermore, the fitting of the rheological curve employs a moving average filter to remove high-frequency noise, and the torque fluctuation rate is calculated using the filtered torque value.

[0021] Furthermore, the dynamic threshold is determined as follows: the automatic control cabinet dynamically sets it based on the preset type of curing agent raw material and the real-time detected ambient temperature.

[0022] Furthermore, in step S2, the solidifying agent raw material in the raw material storage tank is fed into the upper mixing chamber, and in step S3, water is injected into the upper mixing chamber from the water tank. A time-division multiplexing strategy is adopted, and water injection is started again after a set delay after the weight sensor detects the signal that the feeding is completed.

[0023] Based on the same inventive concept, the present invention provides a method for producing fluidized solidified soil, comprising:

[0024] Excavate a mud pit near the construction site and add mud;

[0025] Using the above-described method for preparing curing agent slurry, a curing agent slurry is prepared and stored in a curing agent slurry preparation tank;

[0026] The curing agent slurry in the curing agent slurry preparation tank is pumped through pipeline to the mud tank and stirred into a fluidized solidified soil;

[0027] The fluidized solidified soil is transported to the pouring point by pumping or chute to complete the pouring.

[0028] Furthermore, the mud is made by mixing soil and water, or by directly using waste mud generated during the construction of cast-in-place piles.

[0029] Beneficial effects: Compared with the prior art, the significant technical effects of the present invention are as follows:

[0030] (1) In the production method of fluidized solidified soil of the present invention, a "two-step" process of preparing solidified agent and fluidized solidified soil in steps is adopted. The solidified agent is prepared and stored in advance in the form of slurry. The fluidized solidified soil is produced near the construction site. Only the slurry and water need to be transported by pipeline. There is no need for transport vehicles to transfer materials on site, reducing the transfer links, avoiding the loss of fluidity caused by long-distance transportation of fluidized solidified soil, improving construction efficiency and reducing costs.

[0031] (2) In the curing agent slurry preparation device of the present invention, a double-layer mixing chamber structure of upper mixing chamber + lower mixing chamber is adopted. The upper layer is used for batching and preliminary mixing, and the lower layer is used for full mixing and discharge. The upper and lower layers alternate and operate in parallel to realize continuous production and improve equipment utilization. The weight sensor collects the feed weight change curve in real time, identifies the over-drop amount and dynamically corrects the stop advance of the next auger, reduces batching error and improves formula stability.

[0032] (3) The torque of the agitator is collected in real time during the lower layer mixing process, the rheological curve of the slurry is fitted, and the timing of homogeneity is determined by the torque fluctuation rate. This replaces fixed-duration mixing or manual sampling and testing, realizes in-situ non-destructive monitoring and adaptive discharge of slurry quality, and reduces quality fluctuations caused by over-mixing or under-mixing.

[0033] (4) Each actuator is electrically connected to the automatic control cabinet and runs automatically through a preset program, reducing the intensity of manual intervention and ensuring stable production cycle.

[0034] (5) When preparing fluidized solidified soil, the mud can also be the waste mud generated during the construction of cast-in-place piles. On the one hand, it simplifies the mud preparation process, and on the other hand, it fundamentally solves the problem of waste mud disposal in construction projects, realizing the resource utilization of waste mud. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the present invention;

[0036] Figure 2 This is a structural schematic diagram of the present invention from another angle. Detailed Implementation

[0037] The technical solution of the present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0038] Example 1

[0039] This invention provides a curing agent slurry preparation device, the core of which is to achieve high-precision and continuous preparation of curing agent slurry through structural design and automated control, adapting to the construction needs of on-site production of fluidized solidified soil. For example... Figure 1 and Figure 2 As shown, the curing agent slurry preparation device includes a raw material storage tank 1, an upper mixing chamber 2, a lower mixing chamber 3, an automatic control cabinet 4, and a water tank 5.

[0040] The raw material storage tank 1 is fixed to a predetermined position on the construction site by a bracket. Its bottom outlet is sealed to the feed end of the auger (i.e., screw conveyor) to ensure that there is no leakage and the material is discharged smoothly during the transportation of the solid curing agent raw material. The raw material storage tank 1 is connected to the upper mixing chamber 2 through the auger.

[0041] The upper mixing chamber 2 is precisely aligned with the discharge end of the auger, ensuring that the raw materials fall completely into the upper mixing chamber 2. A weight sensor is installed below the upper mixing chamber 2 to collect the weight of the upper mixing chamber 2 in real time. In this embodiment, the upper mixing chamber 2 adopts a rigid structure design, and the weight sensor is installed on the rigid support part on the lower side of the bottom wall of the upper mixing chamber 2. This weight sensor is an industrial-grade weighing sensor with a range of 0-500kg and an accuracy of ±0.1%, avoiding interference from the weight detection accuracy caused by the vibration of the chamber during the mixing process. It can capture the weight change data of the material in the chamber in real time and transmit it to the automatic control cabinet 4.

[0042] The upper mixing chamber 2 is equipped with a first agitator; in this embodiment, the first agitator adopts a paddle-type structure with an optimized blade angle. The drive motor of the first agitator is electrically connected to the automatic control cabinet 4, and the automatic control cabinet 4 adjusts the mixing speed of the first agitator according to a preset program.

[0043] The bottom wall of the upper mixing chamber 2 is equipped with a first valve, which connects to the lower mixing chamber 3 via a vertical pipe. The connection between the vertical pipe and the first valve is sealed to prevent slurry leakage. The bottom wall of the lower mixing chamber 3 is equipped with a second valve, which connects to the curing agent slurry preparation tank via a pipe. The first valve on the bottom wall of the upper mixing chamber 2 is an electrically controlled ball valve, and the second valve on the bottom wall of the lower mixing chamber 3 is also an electrically controlled ball valve. The opening and closing stroke of the valves is precisely controlled by the automatic control cabinet 4 to ensure that the slurry can be delivered quickly and completely and that there is no leakage when it is closed.

[0044] A second agitator is installed in the lower mixing chamber 3. This second agitator employs a double-layer blade structure, with the upper and lower blades arranged alternately to enhance the shearing and mixing effect on the slurry and improve homogeneity. A torque sensor is fixedly installed on the drive shaft end of the second agitator. This torque sensor is a high-precision sensor with a measurement range of 0-100 N·m and a sampling frequency ≥10 Hz, capable of collecting torque data in real time during the mixing process and synchronously transmitting the data to the automatic control cabinet 4. The discharge port of the lower mixing chamber 3 is connected to the curing agent slurry preparation tank via a high-pressure pipeline. The delivery pump on the pipeline is linked to the second valve for control, ensuring the stability of the slurry delivery.

[0045] Water tank 5 is located on one side of raw material storage tank 1. Its inlet pipe is connected to the water storage tank via a solenoid valve. A water level sensor is installed on the inner wall of water tank 5. When the water level in water tank 5 is lower than the preset full-water-level threshold, the water level sensor sends a signal to automatic control cabinet 4. Automatic control cabinet 4 then controls the solenoid valve to open, replenishing water into water tank 5 until the water level reaches full, at which point the solenoid valve closes, maintaining water tank 5 at a full water level and ensuring the continuity of the water injection process. A flow meter is connected in series on the outlet pipe of water tank 5. This flow meter accurately measures the amount of water injected into the upper mixing chamber 2, and the measurement data is fed back to automatic control cabinet 4 in real time, enabling precise control of the water volume through valves. The outlet pipe of water tank 5 is connected to the upper mixing chamber 2.

[0046] The auger, first agitator, first valve, weight sensor, second agitator, torque sensor, second valve, water level sensor, and flow meter are all electrically connected to the automatic control cabinet 4. The automatic control cabinet 4 has a built-in programmable logic controller (PLC) that pre-stores data such as the curing agent slurry's formulation parameters, mixing program, and threshold settings. All actuators and detection components, including the auger, first agitator, first valve, weight sensor, second agitator, second valve, water level sensor, flow meter, and delivery pump, are electrically connected to the automatic control cabinet 4 via cables, forming a complete automated control loop. Simultaneously, the automatic control cabinet 4 has a built-in fault handling program. When the weight sensor's data acquisition error exceeds ±0.5% for three consecutive times, an alarm will be triggered and the machine will stop. When the torque fluctuation rate remains above the threshold for 10 minutes, the mixing time will be automatically extended by 30 seconds; if the result is still unsatisfactory, the machine will stop and the raw material ratio will be checked.

[0047] Example 2

[0048] The present invention provides a method for preparing a curing agent slurry, which is applied to the curing agent slurry preparation apparatus of Example 1, and includes the following steps:

[0049] S1. Start the preset automatic control program in the automatic control cabinet 4, and fill the water tank 5 to full. Details are as follows:

[0050] During the preparation of the curing agent slurry, the preset control program in the automatic control cabinet 4 is first started, and the system enters the initialization state. The water level sensor detects the water level in the water tank 5. If the water level is not full, the automatic control cabinet 4 controls the solenoid valve of the water inlet pipe to open, and water is injected from the water storage tank into the water tank 5 until the water level sensor detects the full water level signal, the solenoid valve closes, and the water tank 5 remains at the full water level.

[0051] S2. Automatic control cabinet 4 controls the auger to add the curing agent raw material from raw material storage tank 1 into upper mixing chamber 2 according to the preset formula. Weight sensors collect real-time weight change data from upper mixing chamber 2, generate a weight change curve, and transmit it to automatic control cabinet 4. Automatic control cabinet 4 calculates the excess material discharge amount for this batch based on the weight change curve and uses this excess material discharge amount to calculate the correction value for the auger shutdown advance time for the next batch. Details are as follows:

[0052] In step S2, the automatic control cabinet 4 calculates the excess material discharge amount of the current tray based on the weight change curve, and uses the excess material discharge amount to calculate the correction value for the auger shutdown advance of the next tray, as follows:

[0053] Automatic control cabinet 4 performs differential calculation on the weight change curve, identifies the abrupt change point of the feeding rate, and calculates the difference between the steady-state weight after the abrupt change point of the feeding rate and the preset target weight to obtain the overfeed amount of the raw material in this tray.

[0054] Automatic control cabinet 4 uses an iterative learning algorithm to calculate the weighted average of the overfeed amount of the three most recent raw material trays, and obtain the correction value for the lead time of the auger shutdown in the next tray.

[0055] In this embodiment, after entering the raw material feeding stage, the auger starts according to the preset curing agent formula ratio and feeding sequence, transporting the solid curing agent raw material in the raw material storage tank 1 to the upper mixing chamber 2. During this process, the weight sensor collects the weight change data of the upper mixing chamber 2 in real time, generates a weight change curve and transmits it to the automatic control cabinet 4. The automatic control cabinet 4 performs differential calculation on the weight change curve (i.e., the area difference between the integral area of ​​the actual change curve and the integral area of ​​the theoretical change curve), and identifies the abrupt change point of the feeding rate. When the auger stops running, due to inertia, some raw material will still fall into the upper mixing chamber 2. The abrupt change point of the feeding rate corresponds to the moment when the auger actually stops feeding. The automatic control cabinet 4 calculates the difference between the steady-state weight after the abrupt change point and the preset target weight to obtain the over-fall amount of raw material in this pan. Meanwhile, the automatic control cabinet 4 uses an iterative learning algorithm to calculate the weighted average of the over-drop amount of the three most recent raw material trays. The weight of the over-drop amount of the most recent tray is 0.5, the second tray is 0.3, and the third tray is 0.2. This calculates the correction value for the lead time of the auger shutdown in the next tray, providing data support for the accuracy correction of subsequent feeding.

[0056] S3. When the weight sensor detects the completion signal of feeding, the water tank 5 injects water into the upper mixing chamber 2. The flow meter measures the amount of water injected into the upper mixing chamber 2. At the same time as water is injected, the first agitator is started to perform preliminary mixing, so that the curing agent raw material and water can fully contact and mix to form a preliminary slurry.

[0057] In this embodiment, after the weight sensor detects the completion signal of material feeding, the system adopts a time-division multiplexing strategy (i.e., material feeding and water injection are performed simultaneously without overlapping operations). After a delay of 3-5 seconds, the water injection program is started. This delay interval can be flexibly adjusted according to the flow characteristics of the raw materials. The core purpose is to avoid splashing of raw materials in the upper mixing chamber 2 due to water flow impact, thereby causing weighing errors. During the water injection process, the water outlet pipe of the water tank 5 is opened, and the flow meter accurately measures the amount of water injected into the upper mixing chamber 2. When the water volume reaches the preset value, the flow meter sends a signal to the automatic control cabinet 4, and the automatic control cabinet 4 controls the water outlet pipe to close. At the same time as water injection, the first agitator is started and performs preliminary stirring at a preset speed to ensure that the solid raw materials and water are fully contacted and mixed to form a preliminary slurry.

[0058] It should be noted that the addition of curing agent material from raw material storage tank 1 to upper mixing chamber 2 in step S2 and the addition of water from water tank 5 to upper mixing chamber 2 in step S3 adopt a time-division multiplexing strategy. After the weight sensor detects the completion of feeding signal, the water injection is started again after a set delay.

[0059] S4. After water injection is completed, the first agitator continues to agitate for the preset time, and the automatic control cabinet 4 controls the first valve to open, and the initial slurry is injected into the lower mixing chamber 3.

[0060] In this embodiment, after water injection is completed, the first agitator continues to stir for a preset time to ensure preliminary mixing. Then, the automatic control cabinet 4 controls the opening of the first valve on the bottom wall of the upper mixing chamber 2, and the pre-mixed slurry is injected into the lower mixing chamber 3 under gravity.

[0061] S5. After the upper mixing chamber 2 is emptied, the automatic control cabinet 4 controls the first valve to close and controls the first agitator to stop mixing. The automatic control cabinet 4 adjusts the auger stop time according to the correction value and then repeats S2 to S4 to prepare the next batch of ingredients.

[0062] In this embodiment, when the weight sensor detects that the weight in the upper mixing chamber 2 has returned to the initial value, it is determined that the slurry has been completely injected into the lower mixing chamber 3. The automatic control cabinet 4 controls the first valve to close, the first agitator to stop running, and at the same time adjusts the timing of the auger's shutdown according to the previously calculated correction value. The above feeding, weighing, water injection, and preliminary mixing steps are repeated to process the next batch of slurry. At this time, the next batch of slurry is processed in parallel with the mixing and discharge of the lower mixing chamber 3, realizing continuous production and greatly improving equipment utilization.

[0063] S6. Start the second agitator in the lower mixing chamber 3. The torque sensor collects the torque data of the second agitator in real time during the mixing process and transmits the torque data to the automatic control cabinet 4 synchronously. The automatic control cabinet 4 generates a torque change curve based on the torque data, and then fits the rheological curve of the slurry. Based on the rheological curve, it is determined whether the torque fluctuation rate is lower than the preset dynamic threshold. When the torque fluctuation rate is lower than the preset dynamic threshold and is maintained for a set time, the homogeneity is determined to meet the standard.

[0064] The fitting of the rheological curve uses a moving average filter to remove high-frequency noise, and the torque fluctuation rate is calculated based on the filtered torque value.

[0065] In this embodiment, the dynamic threshold is determined as follows: the automatic control cabinet 4 dynamically sets the threshold based on the preset type of curing agent raw material and the real-time detected ambient temperature.

[0066] After the slurry is injected into the lower mixing chamber 3, the second agitator immediately starts and performs thorough mixing at a preset speed. During this process, the torque sensor at the drive shaft end collects the torque data of the second agitator in real time and transmits it to the automatic control cabinet 4. The automatic control cabinet 4 uses a moving average filter to process the torque data, removing high-frequency noise caused by local unevenness of the slurry during mixing, resulting in a smooth torque change curve. The shear stress and shear rate of the slurry are inferred from the torque and substituted into a power-law model of fluid dynamics to fit the rheological curve of the slurry. The automatic control cabinet 4 dynamically sets the torque fluctuation rate threshold according to the preset type of curing agent raw material and the real-time ambient temperature. When the curing agent is a cement-based raw material, the torque fluctuation rate threshold is set to 5%; when it is a lime-based raw material, the threshold is set to 8%. For every 10°C increase in ambient temperature, the threshold is lowered by 1%. When the torque fluctuation rate is lower than this dynamic threshold and remains below it for 30-60 seconds (the set duration can be adjusted according to actual construction needs), the automatic control cabinet 4 determines that the homogeneity of the slurry meets the standard.

[0067] If the homogeneity fails to meet the standard and exceeds the preset mixing time (the preset mixing time is 10 minutes, meaning the standard signal is not triggered after the timeout), the control program of the automatic control cabinet 4 will immediately activate the alarm function and automatically extend the mixing time by 30 seconds, and then re-test the homogeneity. If the standard is still not met after extending the mixing time, the mixing and testing process will be repeated until the homogeneity meets the standard, or the maximum allowable mixing time is reached (the maximum allowable mixing time is preset to 15 minutes), and then the forced discharge procedure will be executed to avoid affecting the slurry performance or causing production to stop due to excessive mixing.

[0068] S7. After the homogeneity meets the standard, the automatic control cabinet 4 controls the second valve to open and starts the delivery pump on the pipeline to pump the fully mixed slurry to the curing agent slurry tank. After the lower mixing chamber 3 is emptied, the second valve is closed. At the same time, the upper mixing chamber 2 has completed the next batch of preliminary mixing and is ready to inject into the lower mixing chamber 3. S5 to S7 are executed in a cycle.

[0069] Once the homogenization meets the standard, the automatic control cabinet 4 opens the second valve on the bottom wall of the lower mixing chamber 3 and simultaneously starts the delivery pump on the pipeline to pump the fully mixed slurry into the curing agent slurry tank for storage. When the torque sensor detects that the torque has returned to the no-load state, it determines that the slurry in the lower mixing chamber 3 has been completely emptied. The automatic control cabinet 4 then closes the second valve, stops the delivery pump, and stops the second agitator. At this time, the upper mixing chamber 2 has completed the initial mixing of the next batch of slurry and is ready to open the first valve to inject the slurry into the lower mixing chamber 3, starting the next cycle.

[0070] Throughout the entire preparation process, all operations are automatically run by the automatic control cabinet 4 according to the preset program without human intervention. This reduces the intensity of manual labor and ensures the stability of the production cycle. At the same time, through over-discharge correction and real-time monitoring of homogeneity, the accuracy of slurry preparation and quality stability are ensured, which greatly improves production efficiency and equipment utilization.

[0071] Example 3

[0072] The production of fluidized solidified soil requires the use of the aforementioned solidifying agent slurry preparation device. A method for producing fluidized solidified soil according to the present invention comprises the following steps:

[0073] Includes the following steps:

[0074] Step 1: Excavate a mud pit near the construction site and add mud; details are as follows:

[0075] Excavate a mud pit and prepare the mud slurry nearby: Based on the pouring volume at the current construction site, excavate a mud pit on-site near the pouring area. The length, width, and depth of the mud pit are designed according to the total volume of a single or batch pouring to ensure sufficient mud volume and facilitate subsequent mixing operations. Excavate suitable soil from the nearby construction site (no additional transportation required), and add a predetermined amount of soil to the mud pit according to the preset soil-to-water ratio (adjusted according to soil moisture content and target fluidity of the solidified soil, for example, a weight ratio of 1:0.5-1:1.5). Simultaneously, draw clean water from a water storage tank through pipelines and inject it into the mud pit. Start the excavator with professional mixing equipment (such as a hydraulic mixer) to thoroughly mix the soil and water until a uniform, lump-free mud slurry is formed. During the mixing process, a small amount of water or soil can be added according to the consistency of the mud slurry to ensure that the fluidity of the mud slurry meets the requirements for subsequent mixing with the solidifying agent slurry.

[0076] In this step, the mud is made by mixing soil and water, or by directly using the waste mud generated during the construction of the cast-in-place piles.

[0077] Step 2: Using the curing agent slurry preparation method of Example 2, a curing agent slurry is prepared and stored in a curing agent slurry preparation tank. Details are as follows:

[0078] Preparation of curing agent slurry: Simultaneously start the above-mentioned curing agent slurry preparation device, and automatically operate according to the preset curing agent formula (such as the proportion of raw materials such as cement, fly ash, and admixtures) through the automatic control cabinet 4 control device to complete the feeding, weighing, water injection, and stirring of curing agent raw materials, and prepare a uniform curing agent slurry, which is then stored in the curing agent slurry preparation tank for later use, ensuring that the slurry preparation progress matches the mud preparation progress and avoiding waiting.

[0079] Step 3: The curing agent slurry in the curing agent mixing tank is pumped through pipelines to the mud tank and stirred into a fluidized solidified soil. Details are as follows:

[0080] Preparation of fluidized solidified soil: Once the mud and solidifying agent slurry are ready, start the transfer pump between the solidifying agent slurry tank and the mud tank. Pump the solidifying agent slurry into the mud tank through a high-pressure pipeline at a preset ratio (determined according to the strength grade requirements of the fluidized solidified soil, for example, the volume ratio of slurry to mud is 1:5-1:10). During the slurry injection process, continuously start the excavator or professional mixing equipment to ensure that the solidifying agent slurry and mud are fully mixed. The mixing time is adjusted according to the volume of the mixture (generally 0.5-1 hour) until a fluidized solidified soil with uniform texture and good fluidity is formed. During the mixing process, the amount of water or slurry can be finely adjusted by observing the fluidity (such as slump test) to ensure that the fluidized solidified soil meets the requirements for pouring construction.

[0081] Step 4: The fluidized solidified soil is transported to the pouring point using a pump or chute to complete the pouring. Details are as follows:

[0082] Pouring Construction: After the fluidized solidified soil is prepared, it is immediately transported to the pouring point using pumping equipment or chutes. If the construction area is open, an excavator is used to scoop the material and pour it using chutes. If the construction point is narrow (such as a small underground space or around a pipeline) and large vehicles cannot enter, the pipeline is extended directly to the pouring point, and a mud pump is used for pumping to avoid the inefficiency or loss of fluidity caused by vehicle transportation. During the pouring process, the fluidity of the fluidized solidified soil is continuously observed to ensure smooth pouring. After pouring, it is cured according to conventional curing requirements until it solidifies and takes shape.

[0083] Once the pouring at one construction site is completed, if construction is required at the next site, the core steps of fluidized solidified soil production (slurry pit excavation and slurry preparation) can be moved with the construction site, and the above steps can be repeated nearby. Meanwhile, the solidifying agent slurry preparation device remains stationary, and the slurry is simply transported to the new slurry pit through pipelines. There is no need to move the entire equipment, which greatly reduces transportation costs and time.

[0084] Throughout the entire production process of fluidized solidified soil, the solidifying agent slurry and mud are mixed nearby and poured immediately, which minimizes the time from preparation to pouring of fluidized solidified soil and avoids loss of fluidity. There is no need for vehicles to transport materials within the construction site, which is especially suitable for narrow locations or large-area continuous construction scenarios, significantly improving construction efficiency and reducing transportation and labor costs.

Claims

1. A device for preparing a curing agent slurry, characterized in that: Includes raw material storage tank (1), upper mixing chamber (2), lower mixing chamber (3), automatic control cabinet (4), and water tank (5); The raw material storage tank (1) is connected to the upper mixing chamber (2) via an auger. The upper mixing chamber (2) is equipped with a first agitator and a first valve on the bottom wall of the upper mixing chamber (2). The first valve is connected to the lower mixing chamber (3) via a pipe. A weight sensor is provided below the upper mixing chamber (2). The weight sensor is used to collect the weight of the upper mixing chamber (2) in real time. The lower mixing chamber (3) is equipped with a second agitator. A torque sensor is fixedly installed on the drive shaft end of the second agitator. The bottom wall of the lower mixing chamber (3) is equipped with a second valve. The second valve is connected to the curing agent slurry tank through a pipe. The inner wall of the water tank (5) is equipped with a water level sensor, and the water outlet pipe of the water tank (5) is equipped with a flow meter. The water outlet pipe of the water tank (5) is connected to the upper mixing chamber (2). The auger, first agitator, first valve, weight sensor, second agitator, torque sensor, second valve, water level sensor and flow meter are all electrically connected to the automatic control cabinet (4).

2. The curing agent slurry preparation apparatus according to claim 1, characterized in that: The first stirrer adopts a paddle-type structure. The drive motor of the first stirrer is electrically connected to the automatic control cabinet (4). The automatic control cabinet (4) adjusts the stirring speed of the first stirrer according to the preset program.

3. The curing agent slurry preparation apparatus according to claim 1, characterized in that: The second agitator adopts a double-layer blade structure, with the upper and lower blades arranged alternately.

4. A method for preparing a curing agent slurry, characterized in that, This preparation method, applied to the curing agent slurry preparation apparatus of claim 1, includes the following steps: S1. Start the automatic control program preset in the automatic control cabinet (4) and fill the water tank (5) to the full water level; S2. The automatic control cabinet (4) controls the auger to put the curing agent raw material in the raw material storage tank (1) into the upper mixing chamber (2) according to the preset formula. The weight sensor collects the weight change data of the upper mixing chamber (2) in real time, generates a weight change curve and transmits it to the automatic control cabinet (4). The automatic control cabinet (4) calculates the over-drop amount of the raw material in this tray according to the weight change curve, and uses the over-drop amount to calculate the correction value of the auger shutdown advance amount for the next tray. S3. When the weight sensor detects the completion signal of feeding, the water tank (5) injects water into the upper mixing chamber (2), and the flow meter measures the amount of water injected into the upper mixing chamber (2). At the same time as water is injected, the first agitator is started to perform preliminary mixing so that the curing agent raw material and water can fully contact and mix to form a preliminary slurry. S4. After water injection is completed, the first agitator continues to agitate for a preset time. The automatic control cabinet (4) controls the first valve to open, and the initial slurry is injected into the lower mixing chamber (3). S5. After the upper mixing chamber (2) is emptied, the automatic control cabinet (4) controls the first valve to close and controls the first agitator to stop mixing. The automatic control cabinet (4) adjusts the auger stop time according to the correction value and then repeats S2 to S4 to prepare the next batch of ingredients. S6. Start the second agitator in the lower mixing chamber (3). The torque sensor collects the torque data during the mixing process of the second agitator in real time and transmits the torque data to the automatic control cabinet (4) synchronously. The automatic control cabinet (4) generates a torque change curve based on the torque data and then fits the rheological curve of the slurry. Based on the rheological curve, it determines whether the torque fluctuation rate is lower than the preset dynamic threshold. When the torque fluctuation rate is lower than the preset dynamic threshold and is maintained for a set time, it is determined that the homogeneity meets the standard. S7. After the homogeneity meets the standard, the automatic control cabinet (4) controls the second valve to open and starts the delivery pump on the pipeline to pump the fully mixed slurry to the curing agent slurry tank. After the lower mixing chamber (3) is emptied, the second valve is closed. At the same time, the upper mixing chamber (2) has completed the next batch of preliminary mixing and is ready to inject into the lower mixing chamber (3). S5 to S7 are executed in a cycle.

5. The method for preparing the curing agent slurry according to claim 4, characterized in that: The automatic control cabinet (4) calculates the over-discharge amount of the raw material in this tray based on the weight change curve, and uses the over-discharge amount to calculate the correction value for the lead time of the auger shutdown in the next tray, including: The automatic control cabinet (4) performs differential calculation on the weight change curve, identifies the sudden change point of the feeding rate, and calculates the difference between the steady-state weight after the sudden change point of the feeding rate and the preset target weight to obtain the overfeed amount of the raw material in this tray. The automatic control cabinet (4) uses an iterative learning algorithm to weighted average the over-drop amount of the three most recent batches of raw materials to obtain the correction value for the lead time of the next batch of screw conveyor shutdown.

6. The method for preparing the curing agent slurry according to claim 4, characterized in that: The rheological curve was fitted using a moving average filter to remove high-frequency noise, and the torque fluctuation rate was calculated using the filtered torque value.

7. The method for preparing the curing agent slurry according to claim 4, characterized in that, The dynamic threshold is determined as follows: the automatic control cabinet (4) dynamically sets the threshold based on the preset type of curing agent raw material and the real-time ambient temperature.

8. The method for preparing the curing agent slurry according to claim 4, characterized in that: In step S2, the curing agent raw material in the raw material storage tank (1) is put into the upper mixing chamber (2), and in step S3, the water tank (5) is used to inject water into the upper mixing chamber (2). A time-division multiplexing strategy is adopted, and the water injection is started again after a set delay after the weight sensor detects the signal that the feeding is completed.

9. A method for producing fluidized solidified soil, characterized in that, include: Excavate a mud pit near the construction site and add mud; Using the curing agent slurry preparation method according to claim 5, a curing agent slurry is prepared and stored in a curing agent slurry preparation tank; The curing agent slurry in the curing agent slurry preparation tank is pumped through pipeline to the mud tank and stirred into a fluidized solidified soil; The fluidized solidified soil is transported to the pouring point by pumping or chute to complete the pouring.

10. The method for producing fluidized solidified soil according to claim 9, characterized in that: The mud is made by mixing soil and water, or by directly using waste mud generated during the construction of cast-in-place piles.

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