Movable trolley for secondary grouting of double-shield TBM (Tunnel Boring Machine)

Abstract

The invention discloses a movable trolley for secondary grouting of a double-shield TBM, and belongs to the technical field of tunnel construction equipment. In order to solve the problems of non-uniform slurry mixing, inaccurate grouting pressure control, low automation degree and the like of existing double-shield TBM secondary grouting equipment, a slurry storage system and a grouting execution system are borne through a movable supporting table, and the slurry storage system achieves slurry storage and stirring regulation and control through double storage tanks, a spiral stirring paddle and a liquid level monitoring module; the grouting execution system achieves accurate pressure control through cooperation of a double-outlet grouting pump, a pressure sensor and a frequency converter. The central controller receives liquid level and pressure signals and intelligently regulates and controls the rotating speed of the stirring paddle, the rotating speed of the grouting pump and switching of the slurry storage tank. The movable trolley is mainly used for secondary grouting operation in the double-shield TBM construction process, the grouting efficiency and quality can be improved, and tunnel construction safety and stability are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of double-shield TBM construction equipment, and more particularly to a mobile trolley for secondary grouting of a double-shield TBM. Background Art

[0002] During the construction process of a double-shield TBM (full-face tunnel boring machine), secondary grouting is a critical step in ensuring tunnel lining stability, controlling ground deformation, and ensuring waterproofing. However, conventional double-shield TBM mobile trolleys for secondary grouting present technical challenges in slurry management and grouting pressure control. In terms of grouting pressure control, the grouting execution system of traditional trolleys mostly adopts a fixed parameter operation mode. During the grouting process, due to the complex and changeable geological conditions of the tunnel, factors such as pipeline length and slurry viscosity will cause fluctuations in grouting resistance, but the existing system cannot respond to pressure changes in real time. When the grouting pressure is too high, it may cause damage to the tunnel lining structure, resulting in cracks or deformation; if the pressure is too low, it cannot ensure that the slurry fully fills the gaps, resulting in loose grouting, affecting the tunnel's waterproof performance and long-term stability. Moreover, the speed adjustment of traditional grouting pumps relies on manual intervention and has a slow response speed, making it difficult to meet the demand for precise pressure control under complex working conditions.

[0003] However, there are many difficulties in solving the above problems. The mechanism of slurry precipitation and segregation is complex and is affected by many factors such as slurry ratio, standing time, storage environment, etc. Summary of the Invention

[0004] An object of the present invention is to provide a mobile trolley for secondary grouting of a double-shield TBM.

[0005] In order to achieve these objects and other advantages of the present invention, a mobile trolley for secondary grouting of a double-shield TBM is provided, comprising: a mobile support platform, a slurry storage system, a grouting execution system, and a central controller; The slurry storage system includes a first slurry storage tank, a second slurry storage tank, an agitator group, and a liquid level monitoring module. The first slurry storage tank and the second slurry storage tank are fixed on a mobile support platform. The agitator group includes a spiral agitator vertically inserted into the first slurry storage tank and the second slurry storage tank respectively. The liquid level monitoring module uses an ultrasonic sensor installed on the top of the first slurry storage tank and the second slurry storage tank; The grouting execution system includes a dual-outlet grouting pump, a pressure sensor, a frequency converter, a grouting hose, and a grouting nozzle. The inlet end of the dual-outlet grouting pump is connected to the bottom outlet of the first slurry storage tank and the second slurry storage tank through a pipeline. The pressure sensor is embedded in the middle section of the grouting hose, and the end of the grouting hose is connected to the grouting nozzle. The frequency converter is electrically connected to the dual-outlet grouting pump drive motor. The central controller is configured to receive a liquid level signal from the liquid level monitoring module. When the liquid level in the first slurry storage tank drops to a first preset threshold, the central controller sends a first speed regulation instruction to the agitator group, increasing the speed of the propeller agitator in the first slurry storage tank from a base speed of 20 revolutions per minute to 40 revolutions per minute. When the liquid level in the first slurry storage tank drops to a second preset threshold, the central controller sends a second speed regulation instruction, increasing the speed of the propeller agitator to 50 revolutions per minute. The pressure sensor is used to collect the slurry pressure value in the grouting hose in real time. The central controller is connected to the pressure sensor and can obtain the pressure value collected by the pressure sensor. When the pressure data exceeds the set pressure range for 3 seconds, the central controller sends an adjustment instruction to the frequency converter, and the frequency converter adjusts the speed of the dual-outlet grouting pump drive motor; The central controller synchronously controls the switching of the slurry storage system. When the liquid level of the first slurry storage tank drops to the emptying threshold, the central controller starts the screw agitator of the second slurry storage tank to the basic speed of 20 revolutions per minute, and switches the dual-outlet grouting pump to the second inlet connection state.

[0006] Preferably, the grouting execution system is additionally provided with a pressure stabilizing buffer unit, and the pressure stabilizing buffer unit comprises: A buffer tank is connected in parallel to the outlet of the dual-outlet grouting pump. The volume of the buffer tank is 5%-8% of the volume of the first slurry storage tank. An electric regulating valve is installed at the inlet of the buffer tank. A closed-loop control module connected to the pressure sensor and the central controller; When the central controller issues an instruction to switch the slurry storage tank, the closed-loop control module is started synchronously, and the slurry supply amount of the buffer tank is dynamically adjusted through the electric regulating valve to control the pressure fluctuation amplitude in the grouting hose within the set pressure range of ±10%.

[0007] Preferably, the inner wall of the buffer tank is coated with a hydrophobic nano-ceramic coating, and a porous guide grid is provided inside the buffer tank; When the central controller detects that the electric control valve has been open less than 40% for more than 3 minutes, the pulse cleaning program is started: the electric control valve switches back and forth between 20%-60% opening at a frequency of 0.5Hz; at the same time, the output flow of the dual-outlet grouting pump increases by 10% and maintains for 10 seconds.

[0008] Preferably, the pulse cleaning program is started and then executed simultaneously: Adaptive filtering: the pressure sensor switches to pulse follower mode, and its low-pass filter cutoff frequency automatically matches twice the current cleaning pulse frequency; Intelligent sleep repair: the central controller suspends the pressure over-limit judgment function. The sleep time is the same as the pulse cleaning program cycle, and is at least not less than 3 complete pulse cycles.

[0009] Preferably, the slurry storage system further includes a tank temperature control module, and the tank temperature control module includes: a heating tape wound around outer walls of the first slurry storage tank and the second slurry storage tank; a temperature sensor, which is inserted into the bottom of the first slurry storage tank and the second slurry storage tank; The temperature sensor and heating tape are both connected to the central controller. When the propeller of the second slurry storage tank starts to the basic speed, the central controller starts the heating tape according to the temperature sensor data. If the bottom temperature of the tank is less than 10°C, the heating tape is heated to 15°C at a rate of 5°C per minute. During the heating period, the agitator group rotates forward for 10 seconds and reverse for 5 seconds alternately.

[0010] Preferably, when the central controller executes the instruction to switch to the second slurry storage tank, it simultaneously triggers a temperature control pre-check program, which includes the following steps: Read the real-time data of the temperature sensor at the bottom of the second slurry storage tank; If the real-time temperature is lower than 8°C, the heating tape wrapped around the outer wall of the second slurry storage tank is started and heated at a rate of 5°C / minute. At the same time, the slurry storage tank switching operation is delayed until the temperature sensor data reaches above 12°C. During the delay period, the grouting operation state of the first slurry storage tank and the operation of the agitator group are maintained; If the liquid level in the first slurry storage tank drops to the emptying threshold, and the heating time of the second slurry storage tank exceeds 5 minutes and the temperature has not yet reached 12°C, the central controller will immediately execute the emergency switching command, switch the dual-outlet grouting pump to a connected state with the second slurry storage tank, and reduce the speed of the grouting pump drive motor to 60% of the basic speed. At the same time, the heating belt continues to heat at a rate of 10°C / minute; when the temperature of the second slurry storage tank reaches 12°C, the central controller will gradually increase the speed of the grouting pump to normal working state.

[0011] Preferably, when the grouting pump runs at 60% of the base speed after the emergency switch, the central controller executes the dynamic overload protection protocol: Calculate the drive motor load rate in real time, with a sampling frequency of once every 0.1 seconds; When the load rate is > 85% for 2 consecutive seconds, the forward and reverse pulse sequence is started. Forward phase: maintain for 10 seconds, the output torque is 120% of the rated value; reverse phase: maintain for 1 second, the output torque is 1.2 times the real-time motor load rate; The pulse sequence is executed cyclically at a frequency of 0.2 Hz until the load rate drops below 75% or the grouting pump speed returns to normal working state.

[0012] Preferably, the stirrer group further includes a defoaming mechanism, and the defoaming mechanism includes: an ultrasonic vibration plate attached to the inner walls of the first slurry storage tank and the second slurry storage tank; Bubble sensor mounted on the tank top; When the speed of the agitator group increases to above 40 revolutions per minute, the central controller starts the ultrasonic vibration plate, and the bubble sensor monitors the gas content of the slurry in real time; if the gas content exceeds 3% by volume, the speed of the propeller is reduced to 35rpm and the ultrasonic vibration plate is maintained until the gas content meets the standard.

[0013] Preferably, the mobile support platform comprises: A support frame comprising a plurality of vertical columns, the top ends of which are provided with a top operating platform and lateral operating platforms located on both sides of the top operating platform, and the lower ends of the vertical columns are provided with walking wheels; Two pairs of trapezoidal top supports are respectively arranged on both sides of the locomotive track, and each pair of trapezoidal top supports is provided with a walkway plate, and the running wheels are located on the walkway plate; Multiple guardrails are installed on both sides of the top operating platform and the side operating platform; A ladder is provided on the side of the lateral operating platform; A plurality of triangular diagonal braces are provided in the upper middle portion of the vertical columns and connected to the lateral operating platform or the top operating platform; A plurality of horizontal braces are installed between two vertical columns.

[0014] The present invention has at least the following beneficial effects: First, the present invention can effectively avoid the precipitation and segregation of slurry due to long-term static standing through the linkage control of liquid level and stirring speed, ensuring that the slurry injected into the tunnel always maintains uniform and stable performance. The coordinated work of the pressure sensor and the frequency converter can adjust the grouting pressure in real time according to the actual working conditions, preventing excessive pressure from damaging the tunnel structure, or excessive pressure from causing loose grouting, thereby significantly improving the construction quality and reliability of secondary grouting and ensuring the long-term stable operation of the tunnel project; the setting of the pressure stabilizing buffer unit can control the pressure within a reasonable range by dynamically adjusting the slurry supply in links that are prone to pressure fluctuations, such as slurry tank switching. This not only avoids problems such as rupture of the grouting pipeline and slurry leakage caused by sudden pressure changes, but also ensures the stability of the slurry flow rate at the grouting nozzle, allowing the slurry to better fill the tunnel voids, improve the density and uniformity of the grouting, and thus enhance the waterproofness and structural strength of the tunnel lining.

[0015] Second, the hydrophobic nano-ceramic coating and porous guide grid design on the inner wall of the buffer tank, combined with the pulse cleaning program, can effectively reduce the adhesion and accumulation of slurry on the tank wall and in the pipeline, reducing the risk of equipment blockage. This eliminates the need for frequent shutdowns for cleaning of the grouting system, significantly improving the continuous operation time and work efficiency of the equipment, while reducing maintenance costs and workload, ensuring the smooth progress of tunnel construction; the adaptive filtering and intelligent sleep functions in the pulse cleaning program effectively solve the problem of pressure monitoring being susceptible to interference during the cleaning process. The pressure sensor accurately collects data in pulse follower mode, and the central controller avoids misjudgment, ensuring that the cleaning operation can not only completely remove residual slurry from the equipment, but also will not interrupt normal operations due to erroneous triggering of the protection mechanism, further improving the stability and reliability of the grouting system operation; Third, the coordinated work of the tank temperature control module and the agitator group ensures that the slurry can still maintain good fluidity and coagulation characteristics in low-temperature environments. Through the precise heating of the heating tape and the alternating stirring of the agitator, the slurry is heated evenly, avoiding the slurry coagulation and clogging of the pipeline due to too low temperature, or the grouting effect affected by uneven temperature, providing reliable technical support for tunnel grouting construction in cold areas; the dynamic overload protection protocol can monitor the load of the drive motor in real time. When an overload trend occurs, the torque output is adjusted in time through the forward and reverse pulse sequence, effectively solving the motor overload problem caused by slurry blockage, increased resistance, etc. This not only protects key equipment such as motors and grouting pumps and extends their service life, but also reduces downtime caused by equipment failure and improves the overall efficiency of tunnel grouting construction.

[0016] Fourth, the present invention consists of a trolley walkway plate, a trapezoidal top support, walking wheels, vertical columns, horizontal braces, operating platforms on both sides, triangular diagonal braces, a top operating platform, guardrails, ladders and other components. Each component can be installed manually in the tunnel, which simplifies the installation process, improves construction efficiency, and solves the problem that the double-shield TBM needs a passable locomotive, mobility, safety and reliability during secondary grouting; the main material of the present invention is made of square steel with adjustable length to meet the needs of different tunnel sizes. Square steel has good welding performance, mechanical properties and lightness, which ensures the strength, durability and practicality of the device; the trolley of the present invention can ensure the simultaneous implementation of secondary grouting and TBM excavation, and enhances the maneuverability of secondary grouting; the device of the present invention reduces the amount of material used through optimized design, and simplifies the installation and disassembly process, which helps to reduce construction costs.

[0017] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1This is a structural diagram of the mobile support platform described in one of the technical solutions of the present invention; Figure 2 This is a structural schematic diagram of the mobile support platform described in one of the technical solutions of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0020] The present invention provides a mobile trolley for secondary grouting of a double-shield TBM, comprising: a mobile support platform, a slurry storage system, a grouting execution system, and a central controller; The slurry storage system includes a first slurry storage tank, a second slurry storage tank, an agitator group, and a liquid level monitoring module. The first slurry storage tank and the second slurry storage tank are fixed on a mobile support platform. The agitator group includes a spiral agitator vertically inserted into the first slurry storage tank and the second slurry storage tank respectively. The liquid level monitoring module uses an ultrasonic sensor installed on the top of the first slurry storage tank and the second slurry storage tank; The grouting execution system includes a dual-outlet grouting pump, a pressure sensor, a frequency converter, a grouting hose, and a grouting nozzle. The inlet end of the dual-outlet grouting pump is connected to the bottom outlet of the first slurry storage tank and the second slurry storage tank through a pipeline. The pressure sensor is embedded in the middle section of the grouting hose, and the end of the grouting hose is connected to the grouting nozzle. The frequency converter is electrically connected to the dual-outlet grouting pump drive motor. The central controller is configured to receive a liquid level signal from the liquid level monitoring module. When the liquid level in the first slurry storage tank drops to a first preset threshold, the central controller sends a first speed regulation instruction to the agitator group, increasing the speed of the propeller agitator in the first slurry storage tank from a base speed of 20 revolutions per minute to 40 revolutions per minute. When the liquid level in the first slurry storage tank drops to a second preset threshold, the central controller sends a second speed regulation instruction, increasing the speed of the propeller agitator to 50 revolutions per minute. The pressure sensor is used to collect the slurry pressure value in the grouting hose in real time. The central controller is connected to the pressure sensor and can obtain the pressure value collected by the pressure sensor. When the pressure data exceeds the set pressure range for 3 seconds, the central controller sends an adjustment instruction to the frequency converter, and the frequency converter adjusts the speed of the dual-outlet grouting pump drive motor; The central controller synchronizes the switching of the slurry storage systems. When the liquid level in the first slurry storage tank drops to the emptying threshold, the central controller activates the propeller in the second slurry storage tank at a base speed of 20 rpm and switches the dual-outlet grouting pump to the second inlet. The first preset threshold can be set at 30% of the total tank volume, the second preset threshold at 20%, and the emptying threshold at 5%. The base speed of the propeller is 20 rpm, with boost speeds of 40 and 50 rpm, respectively. The pressure range can be adjusted to meet specific grouting requirements, such as 0.3-0.8 MPa for common geological conditions. The first and second slurry storage tanks can be stainless steel cylindrical vessels with a capacity of 2-5 cubic meters. The propellers in the agitator assembly can use corrosion-resistant propeller blades with a diameter of 10-15 cm and a length appropriate to the tank depth. The ultrasonic sensor in the liquid level monitoring module can be a general-purpose sensor with a range of 5-10 meters. The dual-outlet grouting pump can choose a diaphragm pump with a flow rate of 50-100L / min, the pressure sensor can choose a strain gauge pressure sensor with a range of 1MPa, and the frequency converter can choose a general frequency converter that is suitable for the grouting pump motor power. The slurry hose can be made of high-pressure and corrosion-resistant rubber material. In terms of assembly position, the first and second slurry storage tanks are fixedly mounted on the top operating platform of the mobile support platform, the agitator group is vertically installed at the center of the top of the storage tank, and the liquid level monitoring module is installed on the top edge of the storage tank. The dual-outlet grouting pump is installed on the mobile support platform near the outlet of the storage tank, and the pressure sensor is embedded in the middle section of the grouting hose 1-2 meters away from the outlet of the grouting pump. The end of the grouting hose is connected to the grouting nozzle.

[0021] Working Process: The liquid level monitoring module monitors the liquid levels in the storage tanks in real time. When the liquid level in the first slurry storage tank drops to 30% of its total volume, the central controller sends a command to increase the speed of the corresponding propeller to 40 rpm to enhance agitation and prevent slurry sedimentation. When it drops to 20%, the speed is further increased to 50 rpm. A pressure sensor continuously measures the pressure within the grouting hose. If the pressure reading exceeds the 0.3-0.8 MPa range for three consecutive seconds, the central controller uses a frequency converter to adjust the speed of the dual-outlet grouting pump's drive motor to control the grouting pressure. When the liquid level in the first slurry storage tank drops to 5%, the central controller activates the propeller in the second slurry storage tank to 20 rpm and simultaneously switches the dual-outlet grouting pump to the inlet of the second slurry storage tank to resume grouting operations.

[0022] This technical solution, through the linked control of liquid level and stirring speed, effectively prevents sedimentation and segregation of the slurry due to prolonged static standing, ensuring that the slurry injected into the tunnel remains uniform and stable. The coordinated operation of the pressure sensor and frequency converter allows for real-time adjustment of the grouting pressure based on actual operating conditions, preventing excessive pressure from damaging the tunnel structure or insufficient pressure from causing loose grouting. This significantly improves the quality and reliability of secondary grouting and ensures the long-term stable operation of the tunnel project.

[0023] In another technical solution, the grouting execution system is additionally provided with a pressure stabilizing buffer unit, and the pressure stabilizing buffer unit comprises: A buffer tank is connected in parallel to the outlet of the dual-outlet grouting pump. The volume of the buffer tank is 5%-8% of the volume of the first slurry storage tank. An electric regulating valve is installed at the inlet of the buffer tank. A closed-loop control module connected to the pressure sensor and the central controller; When the central controller issues a command to switch the slurry storage tank, the closed-loop control module is started synchronously, and the slurry supply to the buffer tank is dynamically adjusted through the electric control valve to control the pressure fluctuation amplitude in the grouting hose within ±10% of the set pressure range. It is more appropriate for the buffer tank volume to be 6% of the volume of the first slurry storage tank, and ±10% of the set pressure range is used as the pressure fluctuation control target. The opening adjustment range of the electric control valve is 0-100%. The buffer tank can be a cylindrical pressure vessel with a volume between 0.1-0.4 cubic meters depending on the size of the storage tank. The electric control valve can be a pneumatic diaphragm control valve with fast response speed and high adjustment accuracy. The closed-loop control module can use a PLC-based control unit that can stably process pressure sensor data and communicate with the central controller.

[0024] The operating process is as follows: When the central controller issues a command to switch slurry storage tanks, the closed-loop control module is simultaneously activated. A pressure sensor transmits real-time pressure data within the grouting hose to the closed-loop control module. The module then adjusts the opening of the electric control valve based on pressure fluctuations, dynamically controlling the amount of slurry supplied from the buffer tank to the main pipeline. If the pressure is too high, the buffer tank's slurry flow is increased; if the pressure is too low, the flow is reduced. This keeps pressure fluctuations within the grouting hose within ±10% of the set pressure range, preventing sudden pressure changes caused by slurry storage tank switching from impacting grouting results.

[0025] This technical solution, coupled with the installation of a pressure-stabilizing buffer unit, allows for dynamic adjustment of slurry supply to maintain pressure within a reasonable range during pressure fluctuations, such as during tank switching. This not only prevents problems such as rupture of grouting pipelines and slurry leakage caused by sudden pressure changes, but also ensures a stable slurry flow rate at the grouting nozzles, allowing the slurry to better fill tunnel voids, improving the density and uniformity of the grouting, and ultimately enhancing the waterproofness and structural strength of the tunnel lining.

[0026] In another technical solution, the inner wall of the buffer tank is coated with a hydrophobic nano-ceramic coating, and a porous diversion grid is provided inside the buffer tank; When the central controller detects that the electric control valve has been open less than 40% for more than three minutes, a pulse cleaning procedure is initiated: the electric control valve switches back and forth between 20% and 60% opening at a frequency of 0.5 Hz. Simultaneously, the output flow of the dual-outlet grouting pump increases by 10% and remains so for 10 seconds. The hydrophobic nano-ceramic coating on the inner wall of the buffer tank can be made of a silica-based nano-ceramic material with excellent hydrophobicity and wear resistance. The porous diversion grid can be made of stainless steel with a pore size of 5-10 mm and a porosity of 40-60%. In the assembly position, the hydrophobic nano-ceramic coating is evenly applied to the inner wall of the buffer tank, and the porous diversion grid is installed horizontally inside the buffer tank, 10-20 cm from the inlet. The electric control valve is installed on the buffer tank inlet pipe.

[0027] Working Process: The central controller monitors the electric control valve opening in real time. If it detects that the electric control valve opening is less than 40% for more than three minutes, the pulse cleaning process is initiated. The electric control valve switches back and forth between 20% and 60% opening at a frequency of 0.5Hz. Simultaneously, the output flow of the dual-outlet grouting pump increases by 10% and remains for 10 seconds. During this process, the high-speed flow of slurry, as the electric control valve opening changes, flushes the inner wall of the buffer tank and the pipeline. The hydrophobic properties of the hydrophobic nano-ceramic coating effectively remove residual slurry from the inner wall. The porous diversion grid helps to evenly disperse the slurry, enhancing the cleaning effect, preventing blockage within the buffer tank, and ensuring the continuous and stable operation of the grouting system.

[0028] This technical solution, combining a hydrophobic nano-ceramic coating on the inner wall of the buffer tank and a porous diversion grid, along with a pulse cleaning process, effectively reduces slurry adhesion and accumulation on the tank walls and pipes, minimizing the risk of equipment blockage. This eliminates the need for frequent downtime for cleaning of the grouting system, significantly increasing equipment uptime and efficiency while reducing maintenance costs and workload, ensuring smooth progress in tunnel construction.

[0029] In another technical solution, the pulse cleaning program is started and executed synchronously: Adaptive filtering: the pressure sensor switches to pulse follower mode, and its low-pass filter cutoff frequency automatically matches twice the current cleaning pulse frequency; Intelligent sleep mode: The central controller suspends the over-pressure detection function. The sleep duration is the same as the pulse cleaning program, and must last at least three complete pulse cycles. During the pulse cleaning program, the frequency of the electric control valve is fixed at 0.5Hz, with an opening range of 20%-60%. The output flow of the dual-outlet grouting pump is increased by 10% for 10 seconds. The cutoff frequency of the pressure sensor's low-pass filter automatically matches twice the current cleaning pulse frequency, i.e., 1Hz. The pressure sensor can be selected as an intelligent pressure sensor with multiple operating mode switching capabilities, which can be switched to pulse follower mode through software settings.

[0030] The operating process is as follows: After the pulse cleaning program is initiated, the pressure sensor automatically switches to pulse-following mode, and its low-pass filter cutoff frequency is adjusted to 1Hz. This ensures that the sensor only filters signals above 1Hz, preventing the cleaning pulse signal from interfering with pressure data collection. Simultaneously, the central controller suspends its pressure overlimit detection function and enters a sleep state. The sleep duration is the same as the pulse cleaning program cycle, and must be no less than three complete 0.5Hz pulse cycles (i.e., 6 seconds). During the cleaning process, the pressure sensor accurately collects the actual pressure signal, allowing the central controller to avoid misjudging pressure fluctuations caused by cleaning, ensuring stable system operation. After cleaning is complete, the pressure sensor and central controller resume normal operation.

[0031] This technical solution, combined with adaptive filtering and intelligent sleep functions within the pulse cleaning process, effectively addresses the issue of pressure monitoring being susceptible to interference during the cleaning process. The pressure sensor accurately collects data in pulse-following mode, and the central controller avoids misjudgments, ensuring that the cleaning operation thoroughly removes residual slurry from the equipment without interrupting normal operations due to erroneous triggering of protection mechanisms. This further enhances the stability and reliability of the grouting system.

[0032] In another technical solution, the slurry storage system further includes a tank temperature control module, and the tank temperature control module includes: a heating tape wound around outer walls of the first slurry storage tank and the second slurry storage tank; a temperature sensor, which is inserted into the bottom of the first slurry storage tank and the second slurry storage tank; Both the temperature sensor and heating cable are connected to the central controller. When the propeller in the second slurry storage tank starts up and reaches base speed, the central controller activates the heating cable based on the temperature sensor data. If the tank bottom temperature is below 10°C, the heating cable is heated at a rate of 5°C / minute to 15°C. During this heating period, the agitator assembly rotates forward for 10 seconds and reverse for 5 seconds. The heating cable typically heats at a rate of 5°C / minute, with the tank bottom temperature thresholds set at 10°C and 15°C. The agitator assembly rotates forward for 10 seconds and reverse for 5 seconds. The heating cable can be a self-limiting electric heating cable, with power selected based on tank size for automatic temperature adjustment. A Pt100 RTD temperature sensor can be used as the temperature sensor, offering high accuracy and stability. The outer sheath of the heating cable is made of flame-retardant, corrosion-resistant polyolefin. The heating cable is evenly wrapped around the outer walls of the first and second slurry storage tanks, and the temperature sensor is inserted vertically into the center of the tank bottom, 5-10 cm from the bottom.

[0033] The operating process is as follows: When the propeller agitator in the second slurry storage tank is activated to a base speed of 20 rpm, the central controller reads the temperature sensor data. If the tank bottom temperature is less than 10°C, the heating cable is activated at a rate of 5°C per minute. Simultaneously, the agitator group is controlled to rotate forward for 10 seconds and reverse for 5 seconds. Forward rotation stirs the slurry, while reverse rotation helps break up vortices, enhances heat transfer, and evenly distributes heat to the slurry until the tank bottom temperature reaches 15°C. This ensures that the slurry is at the appropriate temperature for grouting operations, preventing poor fluidity or coagulation due to low temperatures.

[0034] This technical solution, in which the tank temperature control module and the agitator assembly work in tandem, ensures that the slurry maintains excellent fluidity and coagulation properties even in low-temperature environments. Through precise heating from the heating tape and alternating stirring from the agitator, the slurry is evenly heated, preventing slurry coagulation and pipe blockage due to low temperatures, or uneven temperatures that affect grouting results. This provides reliable technical support for tunnel grouting operations in cold regions.

[0035] In another technical solution, when the central controller executes the instruction to switch to the second slurry storage tank, it simultaneously triggers a temperature control pre-check program, which includes the following steps: Read the real-time data of the temperature sensor at the bottom of the second slurry storage tank; If the real-time temperature is lower than 8°C, the heating tape wrapped around the outer wall of the second slurry storage tank is started and heated at a rate of 5°C / minute. At the same time, the slurry storage tank switching operation is delayed until the temperature sensor data reaches above 12°C. During the delay period, the grouting operation state of the first slurry storage tank and the operation of the agitator group are maintained; If the liquid level in the first slurry storage tank drops to the emptying threshold, and the second slurry storage tank continues to heat for more than 5 minutes and its temperature still hasn't reached 12°C, the central controller immediately executes an emergency switch command, switching the dual-outlet grouting pump to connect to the second slurry storage tank and reducing the grouting pump drive motor speed to 60% of its base speed. Simultaneously, the heating cable continues to heat at a rate of 10°C / minute. Once the second slurry storage tank temperature reaches 12°C, the central controller gradually increases the grouting pump speed to normal operation. The temperature control pre-check program sets temperature thresholds of 8°C and 12°C, with the heating cable heating rate set at 5°C / minute in normal conditions and 10°C / minute in emergency situations. The grouting pump operates at 60% of its base speed after the emergency switch.

[0036] The operating process is as follows: Before executing the command to switch to the second slurry storage tank, the central controller first reads the real-time data from the temperature sensor at the bottom of the second slurry storage tank. If the real-time temperature is below 8°C, the heating cable wrapped around the outer wall of the second slurry storage tank is immediately activated and heated at a rate of 5°C / minute. The tank switching operation is also delayed, while the grouting operation and the agitator assembly in the first slurry storage tank are maintained. If the second slurry storage tank heats up for more than 5 minutes after the liquid level in the first slurry storage tank drops to the emptying threshold and the temperature still does not reach 12°C, the central controller immediately executes the emergency switch command, switching the dual-outlet grouting pump to connect to the second slurry storage tank. The grouting pump drive motor speed is reduced to 60% of the base speed to reduce the grouting pressure and prevent the low temperature slurry from affecting the grouting quality. At the same time, the heating cable continues to heat at a rate of 10°C / minute. When the temperature of the second slurry storage tank reaches 12°C, the central controller gradually increases the grouting pump speed to normal operation, restoring normal grouting efficiency.

[0037] This technical solution, along with its temperature-controlled pre-check procedure and emergency switching mechanism, fully accounts for the complexities of switching grout tanks in low-temperature environments. By implementing measures such as delayed switching and emergency speed reduction, the system ensures the continuity of grouting operations during the switching process while preventing the impact of low-temperature slurry injection on tunnel quality. Furthermore, in extreme situations, the system rapidly adjusts equipment operating parameters to prevent damage from overload, ensuring the safe and stable operation of the entire grouting system in low-temperature conditions.

[0038] In another technical solution, when the grouting pump runs at 60% of the base speed after emergency switching, the central controller executes the dynamic overload protection protocol: Calculate the drive motor load rate (power load rate) in real time, with a sampling frequency of once every 0.1 seconds; When the load rate is > 85% for 2 consecutive seconds, the forward and reverse pulse sequence is started. Forward phase: maintain for 10 seconds, the output torque is 120% of the rated value; reverse phase: maintain for 1 second, the output torque is 1.2 times the real-time motor load rate; The pulse sequence is executed cyclically at a frequency of 0.2 Hz until the load factor drops below 75% or the grouting pump speed returns to normal operation. The drive motor load factor is sampled every 0.1 seconds. A load factor > 85% for two consecutive seconds is used as a condition for starting the forward and reverse pulse sequence. The forward phase is maintained for 10 seconds, with the output torque at 120% of the rated value. The reverse phase is maintained for 1 second, with the output torque at 1.2 times the real-time motor load factor. The pulse sequence frequency is 0.2 Hz, and the load factor drops below 75% as a condition for stopping the pulse sequence.

[0039] The operating process is as follows: After the emergency switch, when the grouting pump runs at 60% of its base speed, the central controller calculates the drive motor load factor in real time every 0.1 second. If the load factor is detected to be greater than 85% for two consecutive seconds, the forward and reverse pulse sequence is initiated. During the forward rotation phase, the motor maintains this rotation for 10 seconds, increasing the output torque to 120% of the rated value to enhance driving force. During the reverse rotation phase, the motor maintains this rotation for 1 second, with the output torque being 1.2 times the real-time motor load factor. This torque change eliminates any possible slurry blockage or jamming. The pulse sequence is executed cyclically at a frequency of 0.2Hz until the load factor drops below 75% or the grouting pump speed returns to normal operating conditions, effectively preventing motor overload damage and ensuring the continuous and stable operation of the grouting pump.

[0040] This technical solution utilizes a dynamic overload protection protocol that monitors the drive motor load in real time. When overload trends emerge, it promptly adjusts torque output through a forward and reverse pulse sequence, effectively addressing motor overload issues caused by slurry blockage and increased resistance. This not only protects key equipment such as the motor and grouting pump, extending their service life, but also reduces downtime caused by equipment failure, improving the overall efficiency of tunnel grouting operations.

[0041] In another technical solution, the agitator group further includes a defoaming mechanism, which includes: an ultrasonic vibration plate attached to the inner walls of the first slurry storage tank and the second slurry storage tank; Bubble sensor mounted on the tank top; When the agitator speed exceeds 40 rpm, the central controller activates the ultrasonic vibrator, and a bubble sensor monitors the slurry's gas content in real time. If the gas content exceeds 3% by volume, the propeller speed is reduced to 35 rpm, and the ultrasonic vibrator continues operating until the gas content reaches the specified level. When the agitator speed exceeds 40 rpm, the ultrasonic vibrator is activated, the bubble gas content threshold is set to 3%, and the propeller speed is reduced to 35 rpm as a speed adjustment. The ultrasonic vibrator can be a waterproof vibrator with a power of 100-200W, and the bubble sensor can be an infrared gas content sensor that accurately measures the gas content in the slurry. The ultrasonic vibrator housing is made of waterproof, corrosion-resistant plastic. The ultrasonic vibrator is attached to the center of the inner wall of the first and second slurry storage tanks, and the bubble sensor is installed at the center of the tank top.

[0042] The operating process is as follows: When the agitator speed increases to above 40 rpm, the central controller activates the ultrasonic vibrator, which uses high-frequency vibration to break bubbles in the slurry. A bubble sensor monitors the slurry's gas content in real time. If the gas content exceeds 3% by volume, indicating excessive bubbles that may affect grouting quality, the central controller reduces the propeller speed to 35 rpm to reduce the generation of new bubbles during agitation. Meanwhile, the ultrasonic vibrator continues to operate to continuously eliminate bubbles until the gas content reaches the specified level, ensuring the density and stability of the grouting slurry.

[0043] This technical solution enables precise control of the slurry's gas content by the defoaming mechanism, effectively avoiding problems such as grouting voids and insufficient strength caused by excessive bubbles. The coordinated adjustment of the ultrasonic vibration plate and the stirring speed effectively eliminates existing bubbles while reducing the formation of new ones, ensuring that the slurry injected into the tunnel meets the required density, enhancing the waterproofing and structural integrity of the tunnel lining, and guaranteeing project quality.

[0044] In another technical solution, Figure 1 and Figure 2 As shown, the mobile support platform includes: The support frame includes a plurality of vertical columns 4, the tops of the plurality of vertical columns 4 are commonly provided with a top operating platform 8, and lateral operating platforms 6 located on both sides of the top operating platform 8, and the lower ends of the vertical columns 4 are provided with walking wheels 3; Two pairs of trapezoidal top supports 2 are respectively provided on both sides of the locomotive track, and each pair of trapezoidal top supports 2 is provided with a walkway plate, and the running wheels 3 are located on the walkway plate; A plurality of guardrails 9 are provided on both sides of the top operating platform 8 and the side operating platform 6; A ladder 10 is provided on the side of the lateral operating platform 6; A plurality of triangular braces 7 are provided in the upper middle portion of the vertical columns 4 and connected to the lateral operating platform 6 or the top operating platform 8; There are multiple horizontal braces 4, which are installed between two vertical columns 4. The trolley walkway plate 1 is made of high-strength channel steel and is arranged on both sides of the lower middle part of the tunnel along the axis, straddling the locomotive track. The trapezoidal top brace 2 is made of high-strength square steel and steel pipe welded together. Its bottom is supported on the locomotive track, and its upper part supports the trolley walkway plate 1. There are four running wheels 3 in total, which are of the type of internal steel wheels and external solid rubber wheels. An inverted triangular concave seat is provided on the upper part and installed at the bottom of the trolley. There are four vertical columns 4 in total, which are made of high-strength square steel. Its bottom is connected to the running wheel 3, its upper middle part is connected to the triangular diagonal brace 7, and its upper part is connected to the operating platform. There are four horizontal braces 4 in total, which are made of high-strength square steel and installed between the two vertical columns 4. The operating platforms on both sides are arranged on the outside of the vertical columns 4 and are fixed by triangular diagonal braces 7. Six triangular braces 7 are installed on each side of the upper middle portion of the vertical columns 4. Two of these connect the vertical columns 4 and the lateral operating platform 6, and the remaining two connect the vertical columns 4 and the top operating platform 8. They are constructed from high-strength square steel to form a ring frame, which is then fully clad with pitted steel plates. The top operating platform 8 is located atop the vertical columns 4 and is constructed from high-strength square steel to form a ring frame, which is then fully clad with pitted steel plates. Guardrails 9 are installed on both sides of the operating platform, made from small high-strength square steel, with height adjustable according to actual conditions. A ladder 10, also made from high-strength square steel, is installed at the edge of the lateral operating platform 6.

[0045] The installation method of the mobile support platform includes the following steps: S1: Welding is performed outside the hole to form each component. Enlarged pads are added and holes are drilled at the connection points of each component to facilitate bolt connection. S2: clamp the bottom of the trapezoidal top support 2 on the locomotive track; S3: Place the trolley walkway plate 1 on the trapezoidal top support 2; S4: Install the travel wheel 3 on the vertical column 4 and fix it with an iron shoe; S5: Connect the vertical column 4 with the horizontal brace 4; S6: Connect the vertical column 4 with the top operating platform 8 and the triangular brace 7; S7: Connect the operating platforms on both sides to the vertical columns 4 and the triangular braces 7; S8: Install the ladder 10 and connect it to the vertical column 4 and the side operating platform; S9: Install guardrail 9.

[0046] By adopting this technical solution, the present invention is composed of a trolley walkway plate 1, a trapezoidal top support 2, a walking wheel 3, a vertical column 4, a horizontal support 4, operating platforms on both sides, a triangular diagonal support 7, a top operating platform 8, a guardrail 9, a ladder 10 and other components. Each component can be installed manually in the tunnel, which simplifies the installation process, improves construction efficiency, and solves the problem that the double-shield TBM needs a movable locomotive that can pass through during secondary grouting, and is safe and reliable. The main material of the present invention is made of square steel with adjustable length to meet the requirements of different tunnel sizes. Square steel has good welding performance, mechanical properties and lightness, which ensures the strength, durability and practicality of the device. The trolley of the present invention can ensure the simultaneous implementation of secondary grouting and TBM excavation, thereby enhancing the maneuverability of secondary grouting. The device of the present invention reduces the amount of material used through optimized design, while simplifying the installation and disassembly process, which helps to reduce construction costs.

[0047] The number of equipment and processing scale described here are used to simplify the description of the present invention. Applications, modifications and variations of the mobile trolley for secondary grouting of the double shield TBM of the present invention will be obvious to those skilled in the art.

[0048] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. Mobile trolley for secondary grouting of double shield TBM, characterized by: include: Mobile support platform, slurry storage system, grouting execution system and central controller; The slurry storage system includes a first slurry storage tank, a second slurry storage tank, an agitator group, and a liquid level monitoring module. The first slurry storage tank and the second slurry storage tank are fixed on a mobile support platform. The agitator group includes a spiral agitator vertically inserted into the first slurry storage tank and the second slurry storage tank respectively. The liquid level monitoring module uses an ultrasonic sensor installed on the top of the first slurry storage tank and the second slurry storage tank; The grouting execution system includes a dual-outlet grouting pump, a pressure sensor, a frequency converter, a grouting hose, and a grouting nozzle. The inlet end of the dual-outlet grouting pump is connected to the bottom outlet of the first slurry storage tank and the second slurry storage tank through a pipeline. The pressure sensor is embedded in the middle section of the grouting hose, and the end of the grouting hose is connected to the grouting nozzle. The frequency converter is electrically connected to the dual-outlet grouting pump drive motor. The central controller is configured to receive a liquid level signal from the liquid level monitoring module. When the liquid level in the first slurry storage tank drops to a first preset threshold, the central controller sends a first speed regulation instruction to the agitator group, increasing the speed of the propeller agitator in the first slurry storage tank from a base speed of 20 revolutions per minute to 40 revolutions per minute. When the liquid level in the first slurry storage tank drops to a second preset threshold, the central controller sends a second speed regulation instruction, increasing the speed of the propeller agitator to 50 revolutions per minute. The pressure sensor is used to collect the slurry pressure value in the grouting hose in real time. The central controller is connected to the pressure sensor and can obtain the pressure value collected by the pressure sensor. When the pressure data exceeds the set pressure range for 3 seconds, the central controller sends an adjustment instruction to the frequency converter, and the frequency converter adjusts the speed of the dual-outlet grouting pump drive motor; The central controller synchronously controls the switching of the slurry storage system. When the liquid level of the first slurry storage tank drops to the emptying threshold, the central controller starts the screw agitator of the second slurry storage tank to the basic speed of 20 revolutions per minute, and switches the dual-outlet grouting pump to the second inlet connection state.

2. The mobile trolley for secondary grouting of a double-shield TBM according to claim 1, characterized in that: The grouting execution system is additionally provided with a pressure stabilizing buffer unit, and the pressure stabilizing buffer unit comprises: A buffer tank is connected in parallel to the outlet of the dual-outlet grouting pump. The volume of the buffer tank is 5%-8% of the volume of the first slurry storage tank. An electric regulating valve is installed at the inlet of the buffer tank. A closed-loop control module connected to the pressure sensor and the central controller; When the central controller issues an instruction to switch the slurry storage tank, the closed-loop control module is started synchronously, and the slurry supply amount of the buffer tank is dynamically adjusted through the electric regulating valve to control the pressure fluctuation amplitude in the grouting hose within the set pressure range of ±10%.

3. The mobile trolley for secondary grouting of the double-shield TBM according to claim 2, characterized in that: The inner wall of the buffer tank is coated with a hydrophobic nano-ceramic coating, and a porous diversion grid is arranged inside the buffer tank; When the central controller detects that the electric control valve has been open less than 40% for more than 3 minutes, the pulse cleaning program is started: the electric control valve switches back and forth between 20%-60% opening at a frequency of 0.5Hz; at the same time, the output flow of the dual-outlet grouting pump increases by 10% and maintains for 10 seconds.

4. The mobile trolley for secondary grouting of a double-shield TBM according to claim 3, characterized in that: The pulse cleaning program is started and executed synchronously: Adaptive filtering: the pressure sensor switches to pulse follower mode, and its low-pass filter cutoff frequency automatically matches twice the current cleaning pulse frequency; Intelligent sleep repair: the central controller suspends the pressure over-limit judgment function. The sleep time is the same as the pulse cleaning program cycle, and is at least not less than 3 complete pulse cycles.

5. The mobile trolley for secondary grouting of a double-shield TBM according to claim 1, characterized in that: The slurry storage system further includes a tank temperature control module, which includes: a heating tape wound around outer walls of the first slurry storage tank and the second slurry storage tank; a temperature sensor, which is inserted into the bottom of the first slurry storage tank and the second slurry storage tank; The temperature sensor and heating tape are both connected to the central controller. When the propeller of the second slurry storage tank starts to the basic speed, the central controller starts the heating tape according to the temperature sensor data. If the bottom temperature of the tank is less than 10°C, the heating tape is heated to 15°C at a rate of 5°C per minute. During the heating period, the agitator group rotates forward for 10 seconds and reverse for 5 seconds alternately.

6. The mobile trolley for secondary grouting of a double-shield TBM according to claim 5, characterized in that: When the central controller executes the instruction to switch to the second slurry storage tank, it simultaneously triggers the temperature control pre-check program, which includes the following steps: Read the real-time data of the temperature sensor at the bottom of the second slurry storage tank; If the real-time temperature is lower than 8°C, the heating tape wrapped around the outer wall of the second slurry storage tank is started and heated at a rate of 5°C / minute. At the same time, the slurry storage tank switching operation is delayed until the temperature sensor data reaches above 12°C. During the delay period, the grouting operation state of the first slurry storage tank and the operation of the agitator group are maintained; If the liquid level in the first slurry storage tank drops to the emptying threshold, and the heating time of the second slurry storage tank exceeds 5 minutes and the temperature has not yet reached 12°C, the central controller will immediately execute the emergency switching command, switch the dual-outlet grouting pump to a connected state with the second slurry storage tank, and reduce the speed of the grouting pump drive motor to 60% of the basic speed. At the same time, the heating belt continues to heat at a rate of 10°C / minute; when the temperature of the second slurry storage tank reaches 12°C, the central controller will gradually increase the speed of the grouting pump to normal working state.

7. The mobile trolley for secondary grouting of a double-shield TBM according to claim 6, characterized in that: After the emergency switch, when the grouting pump runs at 60% of the base speed, the central controller executes the dynamic overload protection protocol: Calculate the drive motor load rate in real time, with a sampling frequency of once every 0.1 seconds; When the load rate is > 85% for 2 consecutive seconds, the forward and reverse pulse sequence is started. Forward phase: maintain for 10 seconds, the output torque is 120% of the rated value; reverse phase: maintain for 1 second, the output torque is 1.2 times the real-time motor load rate; The pulse sequence is executed cyclically at a frequency of 0.2 Hz until the load rate drops below 75% or the grouting pump speed returns to normal working state.

8. The mobile trolley for secondary grouting of a double-shield TBM according to claim 1, characterized in that: The agitator group further includes a defoaming mechanism, which includes: an ultrasonic vibration plate attached to the inner walls of the first slurry storage tank and the second slurry storage tank; Bubble sensor mounted on the tank top; When the speed of the agitator group increases to above 40 revolutions per minute, the central controller starts the ultrasonic vibration plate, and the bubble sensor monitors the gas content of the slurry in real time; if the gas content exceeds 3% by volume, the speed of the propeller is reduced to 35rpm and the ultrasonic vibration plate is maintained until the gas content meets the standard.

9. The mobile trolley for secondary grouting of a double-shield TBM according to claim 1, characterized in that: The mobile support platform includes: A support frame comprising a plurality of vertical columns, the top ends of which are provided with a top operating platform and lateral operating platforms located on both sides of the top operating platform, and the lower ends of the vertical columns are provided with walking wheels; Two pairs of trapezoidal top supports are respectively arranged on both sides of the locomotive track, and each pair of trapezoidal top supports is provided with a walkway plate, and the running wheels are located on the walkway plate; Multiple guardrails are installed on both sides of the top operating platform and the side operating platform; A ladder is provided on the side of the lateral operating platform; A plurality of triangular diagonal braces are provided in the upper middle portion of the vertical columns and connected to the lateral operating platform or the top operating platform; A plurality of horizontal braces are installed between two vertical columns.

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