Inclined shaft TBM slag chute gate control method

Abstract

The application discloses a method for controlling a chute gate of a TBM in an inclined shaft, and belongs to the technical field of tunnel boring machine control. The method monitors the flow rate and height of the slag layer in real time by installing a millimeter wave radar sensor on the gate slide, and detects the lateral pressure of the slag by embedding a pressure sensor on the back of the gate. The PLC controller calculates the real-time slag amount according to the flow rate and height signals, compares it with the target slag amount, and outputs a control signal to drive the telescopic oil cylinder to extend or retract to adjust the gate opening. When the flow rate of the slag suddenly decreases and the pressure exceeds the threshold, the control oil cylinder is alternately retracted and extended to realize gate vibration and unblocking. When the flow rate is zero and the pressure reaches the safety threshold, the gate is fully opened and an audible and visual alarm is triggered. The scheme solves the problems of manual judgment lag and insufficient control accuracy in the blocking of the slag chute during the construction of the inclined shaft, and significantly improves the stability of slag discharge and the efficiency of anti-blocking through multi-source sensor fusion and a hierarchical response mechanism.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine control technology, and in particular to a method for controlling the chute gate of an inclined shaft TBM. Background Technology

[0002] In inclined shaft projects such as pumped storage power stations and mine roadways, full-face tunnel boring machines (TBMs) need to continuously transport crushed rock debris via muck chutes. The inclination angle of the inclined shaft is usually 25°-40°, and the debris tends to accumulate and compact in the chute under gravity. Traditional control relies on operators observing the debris flow and manually adjusting the gate opening.

[0003] When the dust concentration in the inclined shaft exceeds 200 mg / m³, changes in the slag layer thickness cannot be accurately identified visually. Often, issues are only addressed after the chute is completely blocked, leading to shutdowns for slag removal. During the construction of an inclined shaft at a pumped-storage power station, such blockages resulted in an average daily shutdown of 2.3 hours. Manual adjustments are made in 10% increments, but the actual slag volume is affected by variations in rock strata, requiring millimeter-level responses. A 40% opening in sandstone formation resulted in a moderate slag volume, but switching to the same opening in mudstone formation led to a 35% excess slag volume, exacerbating the risk of blockage. Existing gates lack the ability to detect the initial stages of blockage; when the slag flow slows to a critical point, there is no proactive intervention, resulting in sudden blockages accounting for 78% of cases.

[0004] Some existing technologies use laser rangefinders to monitor slag layer height, but the water mist environment in inclined wells causes laser refraction failure, resulting in a high false alarm rate. Other solutions propose pneumatic impact slugging, but this requires pre-embedded pipelines and consumes three times the energy of hydraulic systems, making widespread adoption difficult. Most gate control systems rely solely on preset opening programs and do not integrate real-time slag flow parameters, leading to poor adaptability to changes in rock strata. For these reasons, there is an urgent need to develop an intelligent gate control method that adapts to the complex environment of inclined wells, integrates multi-source sensing, and possesses early warning capabilities. Summary of the Invention

[0005] This invention overcomes the problems of delayed manual judgment and insufficient control precision in the case of chute blockage during inclined shaft construction, and provides a gate control method for chute blockage in inclined shaft TBMs. Through multi-source sensor fusion and hierarchical response mechanism, it significantly improves slag discharge stability and anti-blockage efficiency.

[0006] To achieve the above objectives, the present invention adopts the following solution:

[0007] A method for controlling the gate of the chute in an inclined shaft TBM, wherein the chute gate includes a slide rail, a telescopic cylinder, and the gate itself. The slide rail is fixed at the connection between the bottom shield and the chute. The gate is slidably connected to the bottom shield via the slide rail. One end of the telescopic cylinder is connected to the bottom shield, and the other end is connected to the gate to control the opening degree of the gate. The method includes:

[0008] Millimeter-wave radar sensors are installed on the slides on both sides of the gate to obtain the flow velocity and slag layer height of the slag in the slag chute in real time; pressure sensors are embedded on the surface of the gate facing away from the slag chute to obtain the lateral pressure of the slag on the gate in real time; the flow velocity signal and height signal output by the millimeter-wave radar sensor and the pressure signal output by the pressure sensor are input to the PLC controller.

[0009] The PLC controller calculates the real-time slag volume based on the flow rate and height signals, and compares the real-time slag volume with the target slag volume. When the real-time slag volume is higher than the target slag volume, the PLC controller outputs a first control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to extend and press down to reduce the gate opening. When the real-time slag volume is lower than the target slag volume, the PLC controller outputs a second control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to retract and lift to increase the gate opening.

[0010] The PLC controller continuously monitors the pressure value output by the pressure sensor and the flow rate signal output by the millimeter-wave radar sensor. When the flow rate of the slag exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, the PLC controller outputs a third control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to alternately contract and extend three times within 5 seconds to vibrate and clear the blockage. When the flow rate of the slag continues to drop to zero and the pressure value reaches a preset safety threshold, the PLC controller outputs a fourth control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to contract to the maximum opening of the gate and triggering an audible and visual alarm.

[0011] Preferably, the operation of driving the telescopic cylinder to alternately contract and extend three times within 5 seconds includes:

[0012] The pressure change rate output from the pressure sensor is acquired in real time. If the pressure change rate does not exceed the preset pressure change rate threshold, the single stroke amount is maintained at 40% of the maximum stroke of the telescopic cylinder; if the pressure change rate exceeds the preset pressure change rate threshold, the single stroke amount is adjusted to 70% of the maximum stroke of the telescopic cylinder.

[0013] Based on the set single stroke volume, the specific method for performing alternating contraction and extension operations is as follows:

[0014] First, drive the telescopic cylinder to retract to the current length minus the single stroke amount, then drive the telescopic cylinder to extend to the current length plus the single stroke amount. After completing three alternating actions, return to the opening before vibration.

[0015] As a preferred option, the target slag quantity is generated through the following steps:

[0016] The propulsion speed signal of the TBM tunneling machine control system is obtained through the MODBUS communication protocol. The current cutterhead cross-sectional area value is retrieved from the TBM equipment parameter library. The propulsion speed signal and the cutterhead cross-sectional area value are input into the multiplier module to calculate the theoretical slag volume.

[0017] The flow velocity and slag layer height of the slag in the chute are read in real time by the millimeter-wave radar sensor. The flow velocity is divided by the slag layer height to obtain the velocity-height ratio. A database of slag type correspondences is established, which includes a mapping table of velocity-height ratio and density compensation coefficient under different rock strata geological conditions. The mapping table is queried and the corresponding density compensation coefficient is matched in the mapping table according to the current velocity-height ratio. The theoretical slag volume is multiplied by the corresponding density compensation coefficient to generate the target slag volume. When the velocity-height ratio does not match the data in the mapping table, the density compensation coefficient is kept at the preset default value.

[0018] As a preferred option, the following simplified correction process is performed when using the soil density compensation coefficient:

[0019] After each 10-meter tunneling operation, an offline batch processing correction is performed. The correction operation includes:

[0020] Retrieve the average actual slag volume Q recorded by the millimeter-wave radar sensor within this 10-meter section. S Based on the average TBM propulsion speed within this 10-meter segment With the cross-sectional area A of the cutter head D Calculate the theoretical average slag volume ; Calculate the slag quantity deviation rate ;

[0021] If the absolute value of the slag quantity deviation rate δ is greater than 15%, the current density compensation coefficient will be increased or decreased by 0.1δ, the density compensation coefficient in the mapping table will be updated, and a correction log including the deviation rate value and the new coefficient value will be output to the human-computer interaction terminal.

[0022] As a preferred method, the following self-diagnostic method is adopted in the operation of real-time acquisition of the flow velocity of slag and soil and the height of slag layer in the slag chute:

[0023] A first millimeter-wave radar sensor and a second millimeter-wave radar sensor are symmetrically installed on the slide rails on both sides of the gate. The first flow velocity signal and the first height signal of the first millimeter-wave radar sensor and the second flow velocity signal and the second height signal of the second millimeter-wave radar sensor are acquired synchronously. The signal-to-noise ratio of the first millimeter-wave radar sensor and the signal-to-noise ratio of the second millimeter-wave radar sensor are calculated in real time.

[0024] If the signal-to-noise ratio of any millimeter-wave radar sensor is lower than 0.5, the sensor is deemed to be faulty. If the first millimeter-wave radar sensor fails, the data from the second millimeter-wave radar sensor is used as the valid signal. If the second millimeter-wave radar sensor fails, the data from the first millimeter-wave radar sensor is used as the valid signal.

[0025] When both sensors fail, switch to backup control mode:

[0026] Fix the gate opening to 80% of the previous effective value and send sensor fault code F01 to the human-machine interface terminal;

[0027] In the operation of acquiring the lateral pressure of the slag and soil borne by the gate in real time, when the pressure value output by the pressure sensor jumps from below 2MPa to above 8MPa within 1 second, the pressure sensor data is marked as invalid, and the average pressure value of the most recent 10 seconds is used as the substitute value.

[0028] Preferably, when the PLC controller detects that the rate of decrease in the flow velocity of the excavated soil exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, the following operations are performed:

[0029] Start the vibrating motor at the bottom of the slag chute, set the vibration frequency to 20Hz, and simultaneously disable the opening adjustment function of the telescopic cylinder; monitor the change rate of slag flow velocity after the vibrating motor starts in real time, and stop the vibrating motor when the change rate of slag flow velocity exceeds 0.15m / s;

[0030] Establish a gate operation energy consumption assessment model, record the cumulative stroke of the telescopic cylinder within one hour, and send the cylinder maintenance warning code E02 to the human-machine interface terminal when the cumulative stroke exceeds 500 times the maximum stroke of the telescopic cylinder; when the TBM tunneling machine enters the step change stop stage, turn off the power supply of the millimeter-wave radar sensor and pressure sensor.

[0031] Preferably, when the vibration motor starts, the following preset vibration strategy is executed:

[0032] The current rock stratum type code is obtained in real time from the TBM geological prediction system, and preset vibration parameters are matched according to the rock stratum type code.

[0033] When the rock stratum is coded as mudstone, the vibration frequency is set to 25Hz and the duration is 30 seconds; when the rock stratum is coded as sandstone, the vibration frequency is set to 18Hz and the duration is 20 seconds; when the rock stratum is coded as fault breccia, the vibration frequency is set to 22Hz and the duration is 40 seconds.

[0034] During the operation of the vibratory motor, the hydraulic pressure value of the cylinder is monitored in real time. When the hydraulic pressure value exceeds 85% of the rated pressure of the system, the vibratory motor is stopped immediately, and the telescopic cylinder is driven to retract to 90% of the maximum opening of the gate and maintain it for 60 seconds.

[0035] Preferably, the operations performed after triggering the audible and visual alarm include:

[0036] The system sends a shutdown request signal with the highest priority to the TBM main control system via the CAN bus, continuously records the pressure value output by the pressure sensor, and calculates the pressure change rate per second.

[0037] When the pressure drops to 60% of the preset safety threshold, the first stage of recovery is executed: the telescopic cylinder is driven to retract to 80% of its maximum opening and maintained at that opening for 120 seconds.

[0038] The system monitors the slag flow velocity signal output by the millimeter-wave radar sensor in real time. When the slag flow velocity recovers to 70% of the velocity before the blockage is triggered and the pressure fluctuation range is stable within ±15% of the preset pressure threshold, the second stage of recovery is executed: the gate opening is gradually increased at a rate of 5% per second until the opening required to match the real-time slag volume with the target slag volume is reached; when the pressure rise exceeds 0.5MPa per second during the opening adjustment process, the opening increase is paused and the current state is maintained for 60 seconds; when the gate opening is stable and the pressure value does not exceed 80% of the preset pressure threshold for 300 seconds, the audible and visual alarm is deactivated.

[0039] Preferably, a vibration acceleration sensor is installed on the piston rod surface of the telescopic cylinder to collect axial vibration frequency signals in real time. The vibration frequency signals are then input into the FFT analysis module to extract vibration energy values ​​in the 500Hz-1kHz frequency band.

[0040] When the vibration energy value exceeds 180% of the reference energy value for 10 consecutive seconds, the first-level response is executed: a vibration warning code W01 is sent to the human-machine interface terminal, limiting the single adjustment amplitude of the gate to no more than 20% of the maximum stroke;

[0041] When the vibration energy value exceeds 250% of the reference energy value for 3 consecutive seconds, the second-level response is executed: the gate opening adjustment function is frozen, and a deceleration tunneling command is sent to the TBM main control system.

[0042] A temperature sensor is embedded in the contact surface between the slide and the gate. When the temperature value of the friction interface exceeds the temperature threshold, the slide lubrication device is activated to spray a standard amount of lubricating grease.

[0043] Preferably, a first temperature sensor and a second temperature sensor are symmetrically installed at both ends of the contact surface between the slide and the gate, and the values ​​of the first temperature sensor T1 and the second temperature sensor T2 are acquired in real time.

[0044] The effective friction temperature T is taken as the average of T1 and T2. When the effective friction temperature T exceeds 90℃, the slide rail lubrication device is activated to spray grease. The spraying duration is set according to the following rules:

[0045] If T≤100℃, the spraying time is set to 8 seconds; if 100℃<T≤120℃, the spraying time is set to 12 seconds; if T>120℃, the spraying time is set to 15 seconds.

[0046] After spraying, monitor the temperature drop rate in real time. When the temperature drop rate is below 0.25℃ / second, repeat the spraying operation once, and reduce the duration of the repeated spraying by 4 seconds.

[0047] The present invention includes at least the following beneficial effects: (1) By fusing millimeter-wave radar and pressure sensor data, dynamic closed-loop control of slag quantity is achieved, significantly improving slag discharge stability; the graded anti-blocking mechanism advances the identification of blockage risk to the bud stage; (2) The vibration stroke adaptive adjustment driven by pressure change rate breaks through the limitation of fixed amplitude and improves the success rate of clearing blockage in the event of sudden blockage; the cylinder opening is locked during vibration to avoid mechanical interference; (3) Dual radar signal-to-noise ratio diagnosis and temperature dual sensor mean calculation eliminate dust interference and gravity temperature measurement deviation, ensuring control continuity under extreme working conditions; (4) The slag quantity target generation and segmented correction mechanism based on rock stratum feature mapping significantly enhances the adaptability to geological variation working conditions; (5) The rock stratum matching strategy of vibration motor and lubrication temperature control feedback work together to reduce system energy consumption and extend the life of key components. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structural principle of the inclined shaft TBM slag chute gate of the present invention.

[0049] In the diagram: 1. Slide rail; 2. Telescopic hydraulic cylinder; 3. Gate; 4. Bottom shield. Detailed Implementation

[0050] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0051] The present invention provides a method for controlling the gate of the slag chute in an inclined shaft TBM, such as... Figure 1 As shown, the slag chute gate includes a slide rail 1, a telescopic cylinder 2, and a gate 3. The slide rail 1 is fixed at the connection between the bottom shield 4 and the slag chute. The gate 3 is slidably connected to the bottom shield 4 via the slide rail 1. One end of the telescopic cylinder 2 is connected to the bottom shield 4, and the other end is connected to the gate 3 to control the opening degree of the gate 3. The method includes:

[0052] Millimeter-wave radar sensors are installed on the slide rails 1 on both sides of the gate 3 to obtain the flow velocity and slag layer height of the slag in the slag chute in real time; pressure sensors are embedded on the surface of the gate 3 facing away from the slag chute to obtain the lateral pressure of the slag on the gate 3 in real time; the flow velocity signal and height signal output by the millimeter-wave radar sensor and the pressure signal output by the pressure sensor are input to the PLC controller.

[0053] The PLC controller calculates the real-time slag volume based on the flow rate and height signals, and compares the real-time slag volume with the target slag volume. When the real-time slag volume is higher than the target slag volume, the PLC controller outputs a first control signal to the solenoid valve of the telescopic cylinder 2, driving the telescopic cylinder 2 to extend and press down to reduce the opening of the gate 3. When the real-time slag volume is lower than the target slag volume, the PLC controller outputs a second control signal to the solenoid valve of the telescopic cylinder 2, driving the telescopic cylinder 2 to retract and lift to increase the opening of the gate 3.

[0054] The PLC controller continuously monitors the pressure value output by the pressure sensor and the flow rate signal output by the millimeter-wave radar sensor. When the flow rate of the slag exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, the PLC controller outputs a third control signal to the solenoid valve of the telescopic cylinder 2, driving the telescopic cylinder 2 to alternately contract and extend three times within 5 seconds to vibrate and clear the blockage. When the flow rate of the slag continues to drop to zero and the pressure value reaches a preset safety threshold, the PLC controller outputs a fourth control signal to the solenoid valve of the telescopic cylinder 2, driving the telescopic cylinder 2 to contract to the maximum opening of the gate 3 and triggering an audible and visual alarm.

[0055] The inclined shaft TBM chute gate consists of a slide rail 1, a telescopic cylinder 2, and a gate 3, forming the main mechanical actuator. The slide rail 1, as a rigid metal guide rail, is welded in pairs and fixed to the connecting flange between the TBM bottom shield and the chute. Its core function is to provide vertical sliding constraint for the gate 3. The gate 3 adopts a wear-resistant steel plate structure, with polytetrafluoroethylene (PTFE) sliders embedded on both sides that precisely engage with the slide rail 1, allowing for precise adjustment of the chute outlet opening through up-and-down sliding. The telescopic cylinder 2 is a double-acting hydraulic cylinder, with the cylinder body hinged to the base of the bottom shield 4 and the piston rod hinged to the top support of the gate 3, forming a force transmission chain. When the cylinder extends, the piston rod pushes the gate 3 downward along the slide rail 1, reducing the opening; when the cylinder retracts, the piston rod pulls the gate 3 upward along the slide rail 1, increasing the opening. The opening adjustment accuracy can reach the millimeter level.

[0056] Millimeter-wave radar sensors are deployed in pairs on both sides of the gate 3 via slide rails 1, with the emission angle precisely aligned with the core area of ​​the slag flow in the chute. Their working principle is based on the dust-penetrating characteristics of 77GHz millimeter waves: the slag flow velocity is analyzed through the Doppler effect, and the slag layer height is measured by combining time-domain reflectometry. The sampling frequency is typically set to 5-10Hz to balance real-time performance and anti-interference requirements. Pressure sensors are embedded in the pressure plate on the side of the gate 3 facing away from the slag flow. They use piezoresistive sensing elements to convert the lateral compressive pressure of the slag into an electrical signal, with a range covering 0-20MPa conditions. The PLC controller, acting as the decision-making center, receives the velocity / height and pressure signals from the radar and performs weighted average filtering to effectively eliminate instantaneous disturbances caused by material impact.

[0057] Real-time slag quantity calculation uses a physical model The flow velocity *v* and slag layer height *h* are derived from millimeter-wave radar, and the trough cross-section correction coefficient *k* is dynamically calibrated based on the chute inclination angle (e.g., *k* = 0.87 at a 30° inclination angle). The PLC refreshes the slag volume data every 200ms to ensure real-time control. The target slag volume can be selected from three sources: preset empirical values, manually input values, or other dynamic algorithms as described in the claims (such as rock strata adaptive models). The control decision forms a clear action chain: when the real-time slag volume is higher than the target value, the PLC outputs a first control signal to drive the cylinder to extend, and the gate 3 moves down 5-10mm to reduce the opening; when the real-time slag volume is lower than the target value, it outputs a second control signal to drive the cylinder to retract, and the gate 3 moves up 5-10mm to increase the opening.

[0058] The anti-blockage early warning system establishes a two-level response mechanism. The first-level warning targets mild blockage, triggered when the flow rate decreases by a preset percentage (example range 30%-50%) and the pressure exceeds a preset threshold (example range 5-10 MPa). At this time, the PLC outputs a third control signal to drive the hydraulic cylinder to complete three alternating contractions / extensions within 5 seconds, causing gate 3 to generate high-frequency vibrations of 50-100 mm amplitude, effectively disrupting the slag arch structure. The second-level response targets severe blockage. When the flow rate returns to zero and the pressure reaches a safe threshold (example value 15 MPa), the PLC outputs a fourth control signal to fully contract the hydraulic cylinder, raising gate 3 to its maximum opening to clear the channel, and simultaneously activating the audible and visual alarm (105 dB buzzer and red warning light).

[0059] This solution significantly improves slag discharge stability through multi-source sensing and closed-loop control: millimeter-wave radar penetrates dust to capture slag flow status in real time, enabling a high degree of matching between slag volume control and TBM propulsion speed; the velocity-pressure coupling criterion triggers gate 3 vibration to clear slag in the early stage of clogging, greatly reducing the risk of complete blockage of the chute; automated control replaces manual experience operation, effectively overcoming pain points such as harsh environment in inclined shafts and delayed manual response.

[0060] In another technical solution, the operation of driving the telescopic cylinder 2 to alternately contract and extend three times within 5 seconds includes:

[0061] The pressure change rate output by the pressure sensor is acquired in real time. If the pressure change rate does not exceed the preset pressure change rate threshold, the single stroke amount is maintained at 40% of the maximum stroke of the telescopic cylinder 2; if the pressure change rate exceeds the preset pressure change rate threshold, the single stroke amount is adjusted to 70% of the maximum stroke of the telescopic cylinder 2.

[0062] Based on the set single stroke volume, the specific method for performing alternating contraction and extension operations is as follows:

[0063] First, drive the telescopic cylinder 2 to retract to the current length minus the single stroke amount, then drive the telescopic cylinder 2 to extend to the current length plus the single stroke amount. After completing three alternating actions, return to the opening before vibration.

[0064] The pressure sensor monitors the lateral pressure of the slag and soil on gate 3 in real time, and its output pressure change rate reflects the accelerating trend of slag and soil blockage. The pressure change rate is defined as the slope of the pressure rise per unit time (e.g., MPa / s). A preset pressure change rate threshold is used as the critical point for judging the rate of slag and soil deterioration. This threshold can be set in the range of 0.5-2 MPa / s (example value 1.0 MPa / s). When the pressure change rate does not exceed the threshold, it is judged as slow slag and the single stroke is set to 40% of the maximum stroke of the telescopic cylinder 2 (e.g., 80 mm when the maximum stroke of the cylinder is 200 mm). When the pressure change rate exceeds the threshold, it is judged as rapid slag and the single stroke is increased to 70% of the maximum stroke (140 mm in the same example). This decision is implemented through the threshold comparison module of the PLC to ensure that the vibration intensity matches the severity of the slag and soil blockage.

[0065] Based on the set single stroke amount, the telescopic cylinder 2 is controlled to perform three alternating contraction and extension operations. Using the current cylinder length L0 as a reference: first, the cylinder is driven to contract to L0 minus the single stroke amount (e.g., L0 - 80mm), causing the gate 3 to rise rapidly; then, the cylinder is driven to extend to L0 plus the single stroke amount (e.g., L0 + 80mm), causing the gate 3 to press down and reset. Each "contraction-extension" action takes approximately 1.67 seconds (three times within 5 seconds), creating high-frequency vibration of the gate 3. After the three cycles, the cylinder precisely returns to its original length L0 before vibration, ensuring the opening state does not deviate. The solenoid valve receives pulse signals from the PLC to control the oil flow direction, and the hydraulic system pressure is maintained at 20MPa to ensure a fast response speed.

[0066] Alternating motion causes gate 3 to move vertically back and forth. Its core unblocking mechanism comprises two physical effects: first, a mechanical impact effect, where the instantaneous upward movement of gate 3 pulls up the attached slag and the downward movement shears the arched structure of the slag; second, a dynamic turbulence effect, where periodic opening changes create pressure fluctuations within the chute, disrupting the static friction balance of the slag. A 40% stroke generates moderate amplitude vibration, suitable for loose slag accumulation; a 70% stroke generates large amplitude, strong impact, which can break up hardened slag blocks. During implementation, a pressure drop of 8%-15% can be observed after vibration (example), restoring the continuity of the slag flow.

[0067] By adjusting the stroke amount adaptively according to the pressure change rate, the targeting of vibration clearing is significantly improved, avoiding clearing failure due to insufficient amplitude or mechanical damage caused by excessive amplitude; the opening is accurately reset after alternating motion, ensuring continuous and stable operation of the main control circuit; the synergistic effect of high-frequency mechanical vibration and fluid disturbance efficiently breaks down various types of slag and soil blockage.

[0068] In another technical solution, the target slag quantity is generated through the following steps:

[0069] The propulsion speed signal of the TBM tunneling machine control system is obtained through the MODBUS communication protocol. The current cutterhead cross-sectional area value is retrieved from the TBM equipment parameter library. The propulsion speed signal and the cutterhead cross-sectional area value are input into the multiplier module to calculate the theoretical slag volume.

[0070] The flow velocity and slag layer height of the slag in the chute are read in real time by the millimeter-wave radar sensor. The flow velocity is divided by the slag layer height to obtain the velocity-height ratio. A database of slag type correspondences is established, which includes a mapping table of velocity-height ratio and density compensation coefficient under different rock strata geological conditions. The mapping table is queried and the corresponding density compensation coefficient is matched in the mapping table according to the current velocity-height ratio. The theoretical slag volume is multiplied by the corresponding density compensation coefficient to generate the target slag volume. When the velocity-height ratio does not match the data in the mapping table, the density compensation coefficient is kept at the preset default value.

[0071] A real-time data link is established with the TBM main control system via the MODBUS communication protocol to continuously acquire the advance speed signal (unit: meters per minute). This signal represents the instantaneous speed of the cutterhead's forward excavation, and its sampling frequency is typically 1-5Hz (example value 2Hz). Simultaneously, the cutterhead cross-sectional area value (a fixed constant, such as 28.3 square meters for a circular cutterhead with a diameter of 6 meters) is retrieved from the TBM equipment parameter library. The advance speed signal and the cutterhead cross-sectional area are multiplied by the multiplier module built into the PLC, outputting the theoretical slag volume value (unit: cubic meters per minute). For example, when the advance speed is 3.2 meters per minute, the theoretical slag volume calculation result is 3.2 × 28.3 = 90.56 cubic meters per minute. This process is refreshed every 200 milliseconds to ensure data real-time performance.

[0072] Millimeter-wave radar sensors collect real-time data on the flow velocity (m / s) and height (m) of the slag layer within the slag chute. The PLC calculates the velocity-to-height ratio (velocity / height), which reflects the slag flow characteristics. A low ratio (<0.4) indicates highly viscous slag, while a high ratio (>1.0) indicates loose slag. A pre-established database of slag type correspondences stores typical characteristics of different rock strata: for example, the ratio range for granite strata is 0.6-0.8, with a density compensation coefficient of 1.05; the ratio range for mudstone strata is 0.3-0.5, with a coefficient of 0.92. The PLC compares the current measured ratio with the database entries: if it falls within a certain rock stratum range, the corresponding density compensation coefficient is used; if it does not match (e.g., ratio 0.25 or 1.2), a preset default coefficient is used (selectable range 0.8-1.2, typical value 1.0).

[0073] The final target slag volume is generated by multiplying the theoretical slag volume by a matching density compensation coefficient. For example, multiplying the theoretical slag volume of 90.56 cubic meters per minute by the granite coefficient of 1.05 yields a target slag volume of 95.09 cubic meters per minute. When database matching fails, a default coefficient is used to ensure continuous system operation: theoretical slag volume × 1.0 means directly using the theoretical value as the target. In practice, differences in target slag volumes are observed under different rock strata: the target value for granite is approximately 3-8% higher than the theoretical value, while for mudstone it is 5-10% lower (example). The PLC sends the updated target slag volume to the control core every 5 seconds, driving the gate 3 opening adjustment.

[0074] The target slag quantity generation is adaptively generated based on rock strata characteristics, effectively overcoming control deviations caused by geological changes; the dual-track mechanism of database matching and default values ​​ensures system robustness under extreme working conditions; and the real-time data processing flow significantly improves the matching accuracy between slag quantity and strata characteristics.

[0075] When using the soil density compensation coefficient, the following simplified correction process should be performed:

[0076] After each 10-meter tunneling operation, an offline batch processing correction is performed. The correction operation includes:

[0077] Retrieve the average actual slag volume Q recorded by the millimeter-wave radar sensor within this 10-meter section. S Based on the average TBM propulsion speed within this 10-meter segment With the cross-sectional area A of the cutter head D Calculate the theoretical average slag volume ; Calculate the slag quantity deviation rate ;

[0078] If the absolute value of the slag quantity deviation rate δ is greater than 15%, the current density compensation coefficient will be increased or decreased by 0.1δ, the density compensation coefficient in the mapping table will be updated, and a correction log including the deviation rate value and the new coefficient value will be output to the human-computer interaction terminal.

[0079] Every 10 meters of excavation completed (corresponding to approximately 30-50 minutes of TBM operation time), offline batch processing correction is automatically triggered. The PLC retrieves the actual slag volume data stream recorded by the millimeter-wave radar sensor in that section, removes outliers, and calculates the mean value QS. Simultaneously, the average advance speed V for that section is acquired. T With fixed cutter head cross-sectional area A D V T Step-switching pauses are eliminated using moving average filtering. For example, a segment V T =3.2 m / min, A D When the area is 28.3 square meters, calculate the average theoretical slag volume Q. L =V T ×A D=90.56 cubic meters. This process is performed during the TBM changeover stop interval, and the time is controlled within 20 seconds to avoid affecting tunneling efficiency.

[0080] Calculate the slag quantity deviation rate δ=(Q) L -Q S ) / Q L ×100% (Example: Q) S When the volume is 85 cubic meters, δ = (90.56 - 85) / 90.56 × 100% = 6.14%. An absolute deviation threshold is set, typically ranging from 10% to 20%. If 15% is chosen, coefficient correction is initiated when |δ| > 15%. If δ is positive, it indicates insufficient actual slag volume, and the current density compensation coefficient is increased by 0.1 × |δ|. If δ is negative, it indicates excessive actual slag volume, and the coefficient is decreased by 0.1 × |δ|. For example, when δ = -18%, the coefficient decreases by 0.1 × 18 = 0.018. A step size coefficient of 0.1 balances convergence speed and stability; the updated coefficient immediately overwrites the original value in the database. If |δ| ≤ 15%, the coefficient remains unchanged.

[0081] After the coefficients are updated, the PLC sends a structured correction log to the human-machine interface terminal, containing key parameters: the tunneling mileage range (e.g., 1020-1030 meters), the δ value (e.g., -18%), the old coefficient value (e.g., 1.05), and the new coefficient value (e.g., 1.032). The log is also written to an SD card for backup, supporting subsequent rock strata analysis. Typical correction scenarios observed during implementation were: in sandstone sections, δ was typically -12% to -20%, with the coefficient gradually decreasing; in fault zones, δ could reach +25%, with the coefficient increasing in a stepwise manner. System data after every 100 meters of tunneling can be used to generate coefficient change curves, assisting in verifying the accuracy of stratigraphic division.

[0082] Periodic offline correction significantly reduces the computational burden of online calculations, adapting to the intermittent operation characteristics of TBMs; the deviation rate threshold mechanism avoids control oscillations caused by over-correction; the log system provides data support for geological inversion, forming a closed loop of control-geological co-optimization.

[0083] In another technical solution, the following self-diagnostic method is used in the operation of real-time acquisition of the flow velocity and slag layer height in the slag chute:

[0084] A first millimeter-wave radar sensor and a second millimeter-wave radar sensor are symmetrically installed on the slide rails 1 on both sides of the gate 3. The first flow velocity signal and the first height signal of the first millimeter-wave radar sensor and the second flow velocity signal and the second height signal of the second millimeter-wave radar sensor are acquired synchronously. The signal-to-noise ratio of the first millimeter-wave radar sensor and the signal-to-noise ratio of the second millimeter-wave radar sensor are calculated in real time.

[0085] If the signal-to-noise ratio of any millimeter-wave radar sensor is lower than 0.5, the sensor is deemed to be faulty. If the first millimeter-wave radar sensor fails, the data from the second millimeter-wave radar sensor is used as the valid signal. If the second millimeter-wave radar sensor fails, the data from the first millimeter-wave radar sensor is used as the valid signal.

[0086] When both sensors fail, switch to backup control mode:

[0087] Set the gate opening 3 to 80% of the previous effective value and send sensor fault code F01 to the human-machine interface terminal;

[0088] In the operation of acquiring the lateral pressure of the slag and soil borne by the gate 3 in real time, when the pressure value output by the pressure sensor jumps from below 2MPa to above 8MPa within 1 second, the pressure sensor data is marked as invalid, and the average pressure value of the most recent 10 seconds is used as the substitute value.

[0089] Two independent millimeter-wave radar sensors, including a first sensor and a second sensor, are symmetrically installed on the slide rails 1 on both sides of gate 3, forming a collaborative redundant monitoring architecture. Each sensor synchronously collects the flow velocity signal and slag layer height signal in the core area of ​​the slag flow, with the sampling frequency set to 5-10Hz (example value is 8Hz). The signal-to-noise ratio (SNR) of each sensor is calculated in real time. This indicator reflects the transmission quality of electromagnetic waves in a dusty environment. The normal range of SNR for industrial-grade radar is 1.0-3.0. If the SNR of any sensor remains below the failure threshold (reference range 0.3-0.7, typical value 0.5) for 3 consecutive seconds, it is considered to have failed. For example, in high-concentration dust (>300mg / m³), this threshold is considered too high. 3 This causes the SNR of the first radar to drop to 0.4. The PLC immediately marks the sensor as faulty and switches to data from the second radar. The data from both sensors are transmitted in parallel via the CAN bus, with a switching delay of less than 50 milliseconds.

[0090] If a single sensor fails (e.g., the first radar), the system seamlessly switches to data from the healthy sensor (second radar), and the control core continues to operate without interruption. When both sensors fail simultaneously (e.g., both SNR < 0.5 for 5 seconds), the PLC activates a backup control mode: locking the gate opening to 80% of the last valid opening value (e.g., locking to 48% when the original opening was 60%). This locked value maintains the basic slag discharge rate, while simultaneously sending the standard fault code F01 (meaning "radar system failure") to the human-machine interface terminal, triggering a red pop-up window and a buzzer. Maintenance personnel can manually overwrite the opening value via the terminal menu until the sensor is repaired. In practice, this mode has been able to operate for up to 2 hours without causing blockages.

[0091] The pressure sensor data is refreshed every 100 milliseconds. When a pressure value jumps from a low-pressure state (<2MPa) to a high-pressure state (>8MPa) within 1 second (e.g., from 1.8MPa to 9.3MPa within 0.5 seconds), it is considered a signal anomaly (a physically impossible pressure surge). The PLC automatically marks this data as invalid and uses the average pressure value of the most recent 10 seconds from the historical data buffer as a replacement value (e.g., a 10-second average of 5.2MPa). This replacement value is used until the sensor status is manually confirmed; the control algorithm continues to operate normally during this period. This mechanism effectively resists signal glitches caused by hydraulic shocks, resulting in a low false positive rate.

[0092] The dual-radar redundancy architecture significantly improves the monitoring reliability in dusty environments, while the signal-to-noise ratio diagnostic mechanism accurately isolates failed sensors. The graded response strategy ensures the system's continuous operation capability under extreme conditions, and the pressure surge detection and historical data replacement effectively eliminate the interference of signal anomalies on control.

[0093] In another technical solution, when the PLC controller detects that the rate of decrease in the flow velocity of the excavated soil exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, the following operations are performed:

[0094] Start the vibrating motor at the bottom of the slag chute, set the vibration frequency to 20Hz, and simultaneously disable the opening adjustment function of the telescopic cylinder 2; monitor the change rate of slag flow velocity after the vibrating motor starts in real time, and stop the vibrating motor when the change rate of slag flow velocity exceeds 0.15m / s;

[0095] Establish a gate operation energy consumption assessment model, record the cumulative stroke of telescopic cylinder 2 within one hour, and when the cumulative stroke exceeds 500 times the maximum stroke of telescopic cylinder 2, send cylinder maintenance warning code E02 to the human-machine interface terminal; when the TBM tunneling machine enters the step change stop stage, turn off the power supply of millimeter-wave radar sensor and pressure sensor.

[0096] When the PLC controller detects that the rate of decrease in the slag flow velocity exceeds a preset ratio (preset value controlled between 30% and 50%) and the pressure value exceeds a preset pressure threshold (threshold determined within the range of 8-12 MPa), it immediately starts the vibrating motor at the bottom of the slag chute. The vibration frequency is fixed at 20Hz, which has a better resonance effect on the slag in the inclined shaft. At the same time, the PLC sends a locking command to the solenoid valve of the telescopic cylinder 2, disabling its opening adjustment function to prevent action conflict. The vibrating motor generates vertical excitation force through an eccentric rotor, with an adjustable amplitude range of 2-5mm (example value is 3mm). The vibration wave is transmitted along the bottom plate of the chute to the interior of the slag. The rate of change of slag flow velocity after vibration starts is monitored in real time. When the rate of change exceeds 0.15 meters per second, the blockage is considered successfully cleared, and the vibrating motor stops running immediately. This process usually lasts 10-30 seconds.

[0097] The PLC's built-in stroke accumulator records the travel distance of the telescopic cylinder 2, calculating the cumulative stroke over one hour. When the cumulative value exceeds 500 times the cylinder's maximum stroke (e.g., a threshold of 100 meters for a maximum stroke of 0.2 meters), a warning code E02 (predefined code meaning "cylinder fatigue warning") is sent to the human-machine interface. A yellow warning bar pops up on the interface, and a fault timestamp is stored. Maintenance personnel then schedule preventative maintenance to avoid hydraulic leaks caused by seal failure. In hard rock formations, the cylinder's average daily stroke is approximately 60 meters; this threshold corresponds to a 7-10 day maintenance cycle.

[0098] When the TBM enters the step-change stop phase, the main propulsion cylinder retracts, the cutterhead stops rotating, and the PLC automatically cuts off the power supply to the millimeter-wave radar sensor and pressure sensor. This design avoids measurement distortion caused by dust settling and covering the sensor probes when stationary. The restart signal is linked to the TBM propulsion system: when the main propulsion cylinder pressure exceeds 5MPa, the sensor power supply is restored within 0.5 seconds. Power management extends sensor lifespan by approximately 40% and significantly reduces the failure rate.

[0099] The vibration cleaning and hydraulic cylinder action interlock mechanism completely eliminates the risk of mechanical interference, the early warning system based on actual wear enables visualized management of the life of key components, and the dynamic management of sensor power supply greatly improves the measurement reliability in high dust environments.

[0100] When the vibration motor starts, the following preset vibration strategy is executed:

[0101] The current rock stratum type code is obtained in real time from the TBM geological prediction system, and preset vibration parameters are matched according to the rock stratum type code.

[0102] When the rock stratum is coded as mudstone, the vibration frequency is set to 25Hz and the duration is 30 seconds; when the rock stratum is coded as sandstone, the vibration frequency is set to 18Hz and the duration is 20 seconds; when the rock stratum is coded as fault breccia, the vibration frequency is set to 22Hz and the duration is 40 seconds.

[0103] During the operation of the vibration motor, the hydraulic pressure value of the cylinder is monitored in real time. When the hydraulic pressure value exceeds 85% of the rated pressure of the system, the vibration motor is stopped immediately, and the telescopic cylinder 2 is driven to retract to 90% of the maximum opening of the gate 3 and maintained for 60 seconds.

[0104] The current rock strata type code (e.g., NYY-mudstone / SY-sandstone / DJ-fault breccia) is obtained in real time from the TBM geological prediction system. A pre-stored vibration parameter mapping table is used in the PLC: mudstone is matched with a 25Hz frequency and 30-second duration (mainly for high-cohesion slag); sandstone with an 18Hz frequency and 20-second duration (mainly for low-cohesion slag); and fault breccia with a 22Hz frequency and 40-second duration (mainly for large-diameter boulders). Parameters are calibrated through field tests; for example, 25Hz vibration in mudstone sections increases slag flowability by approximately 70%. The code refresh cycle is 1-3 seconds (dynamically updated as the TBM advances), allowing seamless switching of vibration parameters when rock strata change.

[0105] During the operation of the vibratory motor, the hydraulic pressure value of the telescopic cylinder 2 is read in real time. When the pressure exceeds 85% of the system's rated pressure of 31.5 MPa (i.e., 26.8 MPa), an overload risk is identified. The PLC immediately executes two-level protection: first, it cuts off the power to the vibratory motor to bring it to an emergency stop (response < 0.1 seconds); then, it drives the telescopic cylinder 2 to retract, raising the gate 3 to 90% of its maximum opening (if it is at 100% full opening, it maintains 90% opening), and maintains this state for 60 seconds to release system pressure. The protection is released only when the pressure value drops to a safe range (< 22 MPa).

[0106] When vibration starts and the rock strata change abruptly (e.g., from sandstone to mudstone), the system prioritizes completing the current vibration cycle before switching parameters. If a protective shutdown (e.g., due to overpressure) occurs simultaneously with the rock strata change, the system will reset and restart vibration with the new rock strata parameters. Typical scenario: In the sandstone section, the pressure stabilizes at 20-24 MPa during 18Hz vibration; in the mudstone section, the peak pressure can reach 28 MPa (close to the protection threshold) during 25Hz vibration.

[0107] Geological prediction-driven vibration parameter matching significantly improves the targeting of slag removal, the hydraulic cylinder multi-protection mechanism effectively prevents equipment damage, and the composite working condition processing logic ensures the system's adaptability to all formations.

[0108] In another technical solution, the operations performed after triggering the audible and visual alarm include:

[0109] The system sends a shutdown request signal with the highest priority to the TBM main control system via the CAN bus, continuously records the pressure value output by the pressure sensor, and calculates the pressure change rate per second.

[0110] When the pressure drops to 60% of the preset safety threshold, the first stage of recovery is executed: the telescopic cylinder 2 is driven to retract to 80% of its maximum opening and maintained at that opening for 120 seconds.

[0111] The system monitors the slag flow velocity signal output by the millimeter-wave radar sensor in real time. When the slag flow velocity recovers to 70% of the velocity before the blockage is triggered and the pressure fluctuation range is stable within ±15% of the preset pressure threshold, the second stage of recovery is executed: the gate 3 opening is gradually increased at a rate of 5% per second until the opening required to match the real-time slag volume with the target slag volume is reached; when the pressure value rises by more than 0.5 MPa per second during the opening adjustment process, the opening increase is paused and the current state is maintained for 60 seconds; when the gate 3 opening is stable and the pressure value does not exceed 80% of the preset pressure threshold for 300 seconds, the audible and visual alarm is deactivated.

[0112] In another technical solution, a vibration acceleration sensor is installed on the piston rod surface of the telescopic cylinder 2 to collect axial vibration frequency signals in real time. The vibration frequency signals are then input into the FFT analysis module to extract the vibration energy values ​​in the 500Hz-1kHz frequency band.

[0113] When the vibration energy value exceeds 180% of the reference energy value for 10 consecutive seconds, the first-level response is executed: a vibration warning code W01 is sent to the human-machine interface terminal, and the single adjustment amplitude of gate 3 is limited to no more than 20% of the maximum stroke;

[0114] When the vibration energy value exceeds 250% of the reference energy value for 3 consecutive seconds, the second-level response is executed: the gate opening adjustment function is frozen, and a deceleration tunneling command is sent to the TBM main control system.

[0115] A temperature sensor is embedded in the contact surface between slide 1 and gate 3. When the temperature value of the friction interface exceeds the temperature threshold, the slide lubrication device is activated to spray a standard amount of lubricating grease.

[0116] A vibration acceleration sensor (range ±50g) is mounted on the piston rod surface of the telescopic cylinder 2 to collect axial vibration signals in real time. The signal is processed by an FFT analysis module (sampling frequency 5kHz) to extract the vibration energy value in the 500Hz-1kHz frequency band. This frequency band focuses on the characteristic frequencies of mechanical wear, and the reference energy value is determined through no-load calibration (e.g., 0.05g). 2 / Hz). When the energy value exceeds 180% of the baseline for 10 consecutive seconds (e.g., 0.09g). 2 When the frequency reaches 0.5 Hz, it is determined to be early wear. The PLC sends a warning code W01 (yellow warning) to the human-machine interface terminal, and at the same time limits the single adjustment range of gate 3 to ≤ 20% of the maximum stroke (e.g., limit the range to 40mm when the stroke is 200mm).

[0117] When the vibration energy exceeds the reference value by 250% (e.g., 0.125g) for 3 consecutive seconds... 2When the energy level reaches 100 Hz, a secondary response is triggered. The PLC immediately freezes the gate 3 opening adjustment function (the solenoid valve is locked in the neutral position) and sends a deceleration tunneling command (e.g., reducing the advance speed to 30% of the original value) to the TBM main control system via the Profinet bus. The freeze state continues until the energy value drops below 150% of the baseline, during which time the operator can manually release it. Actual measurements show that freezing can reduce vibration energy by 40-60%.

[0118] A K-type thermocouple temperature sensor (range 0-200℃) is embedded in the friction surface of the slide rail and gate. When the temperature exceeds the threshold (reference value 80-100℃, typical 90℃), the slide rail lubrication device is activated to spray a standard amount of grease (e.g., 20ml each time). The spraying time is fixed at 8 seconds, covering a 1.2-meter-long slide rail 1. The temperature is refreshed every 30 seconds, and the system does not trigger repeatedly within the same lubrication cycle.

[0119] Frequency-focused vibration analysis improves the early wear identification rate, the synergistic protection of freezing and deceleration tunneling avoids equipment damage, and simplified temperature and lubrication control enhances system robustness.

[0120] A first temperature sensor and a second temperature sensor are symmetrically installed at both ends of the contact surface between the slide 1 and the gate 3, and the values ​​of the first temperature sensor T1 and the second temperature sensor T2 are acquired in real time.

[0121] The effective friction temperature T is taken as the average of T1 and T2. When the effective friction temperature T exceeds 90℃, the slide rail lubrication device is activated to spray grease. The spraying duration is set according to the following rules:

[0122] If T≤100℃, the spraying time is set to 8 seconds; if 100℃<T≤120℃, the spraying time is set to 12 seconds; if T>120℃, the spraying time is set to 15 seconds.

[0123] After spraying, monitor the temperature drop rate in real time. When the temperature drop rate is below 0.25℃ / second, repeat the spraying operation once, and reduce the duration of the repeated spraying by 4 seconds.

[0124] Dual PT100 temperature sensors (accuracy ±0.5℃) are symmetrically installed at the slag inlet and outlet ends of the slag-gate contact surface. The temperature values ​​T1 and T2 at both ends are acquired in real time, and the effective friction temperature T = (T1 + T2) / 2 is calculated. This design eliminates the uneven temperature distribution caused by gravity in the inclined shaft (the measured single-point temperature difference can reach 15℃). For example, when T1 = 98℃ and T2 = 82℃, T = 90℃ is taken. The temperature sampling frequency is 1Hz, and the data is filtered using a moving average.

[0125] When the effective temperature T > 90℃, the lubrication system is activated. The spraying time is controlled in three levels: 8 seconds for T ≤ 100℃ (covering normal overheating); 12 seconds for 100℃ < T ≤ 120℃ (to handle moderate heat buildup); and 15 seconds for T > 120℃ (extreme condition protection). For example, triggering a 12-second spray at T = 115℃ consumes 30ml of grease. The spray pressure is constant at 0.8MPa to ensure uniform grease film coverage.

[0126] After spraying, the temperature drop rate (°C / second) is calculated in real time. If the rate is <0.25°C / second (e.g., 0.2°C / second), insufficient lubrication is determined, and repeated spraying is triggered: the duration is reduced by 4 seconds compared to the previous spray (e.g., 8 seconds if the previous spray was 12 seconds). Repeated spraying is performed at most once to avoid over-lubrication. When the temperature drop rate reaches the target (≥0.25°C / second), the lubrication parameter file is updated to optimize subsequent spraying strategies.

[0127] The dual-sensor averaging effectively overcomes the temperature measurement deviation in the inclined well, the stepped duration control achieves precise thermal management, and the temperature drop feedback mechanism dynamically optimizes lubrication efficiency.

[0128] It should be noted that although the steps are described in a specific order above, this does not mean that they must be performed in that order. In fact, some of these steps can be executed concurrently, or even in a different order, as long as the required functionality is achieved. The number of devices and processing scale described herein are for simplification of the invention; applications, modifications, and variations of this invention will be readily apparent to those skilled in the art.

[0129] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for controlling the gate of a slag chute in an inclined shaft TBM, characterized in that, The chute gate includes a slide rail, a telescopic cylinder, and a gate. The slide rail is fixed at the connection between the bottom shield and the chute. The gate is slidably connected to the bottom shield via the slide rail. One end of the telescopic cylinder is connected to the bottom shield, and the other end is connected to the gate to control the opening degree of the gate. The method includes: Millimeter-wave radar sensors are installed on the slides on both sides of the gate to obtain the flow velocity and slag layer height of the slag in the slag chute in real time; pressure sensors are embedded on the surface of the gate facing away from the slag chute to obtain the lateral pressure of the slag on the gate in real time; the flow velocity signal and height signal output by the millimeter-wave radar sensor and the pressure signal output by the pressure sensor are input to the PLC controller. The PLC controller calculates the real-time slag volume based on the flow rate and height signals, and compares the real-time slag volume with the target slag volume. When the real-time slag volume is higher than the target slag volume, the PLC controller outputs a first control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to extend and press down to reduce the gate opening. When the real-time slag volume is lower than the target slag volume, the PLC controller outputs a second control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to retract and lift to increase the gate opening. The PLC controller continuously monitors the pressure value output by the pressure sensor and the flow rate signal output by the millimeter-wave radar sensor. When the flow rate of the slag exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, the PLC controller outputs a third control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to alternately contract and extend three times within 5 seconds to vibrate and clear the blockage. When the flow rate of the slag continues to drop to zero and the pressure value reaches a preset safety threshold, the PLC controller outputs a fourth control signal to the solenoid valve of the telescopic cylinder, driving the telescopic cylinder to contract to the maximum opening of the gate and triggering an audible and visual alarm. The operation of driving the telescopic cylinder to alternately contract and extend three times within 5 seconds includes: The pressure change rate output from the pressure sensor is acquired in real time. If the pressure change rate does not exceed the preset pressure change rate threshold, the single stroke amount is maintained at 40% of the maximum stroke of the telescopic cylinder; if the pressure change rate exceeds the preset pressure change rate threshold, the single stroke amount is adjusted to 70% of the maximum stroke of the telescopic cylinder. Based on the set single stroke volume, the specific method for performing alternating contraction and extension operations is as follows: First, drive the telescopic cylinder to retract to the current length minus the single stroke amount, then drive the telescopic cylinder to extend to the current length plus the single stroke amount. After completing three alternating actions, return to the opening before vibration. A vibration acceleration sensor is installed on the piston rod surface of the telescopic cylinder to collect axial vibration frequency signals in real time. The vibration frequency signals are then input into an FFT analysis module to extract vibration energy values ​​in the 500Hz-1kHz frequency band. When the vibration energy value exceeds 180% of the reference energy value for 10 consecutive seconds, the first-level response is executed: a vibration warning code W01 is sent to the human-machine interface terminal, limiting the single adjustment amplitude of the gate to no more than 20% of the maximum stroke; When the vibration energy value exceeds 250% of the reference energy value for 3 consecutive seconds, the second-level response is executed: the gate opening adjustment function is frozen, and a deceleration tunneling command is sent to the TBM main control system. A temperature sensor is embedded in the contact surface between the slide and the gate. When the temperature value of the friction interface exceeds the temperature threshold, the slide lubrication device is activated to spray a standard amount of lubricating grease. A first temperature sensor and a second temperature sensor are symmetrically installed at both ends of the contact surface between the slide and the gate, and the values ​​of the first temperature sensor T1 and the second temperature sensor T2 are acquired in real time. The effective friction temperature T is taken as the average of T1 and T2. When the effective friction temperature T exceeds 90℃, the slide rail lubrication device is activated to spray grease. The spraying duration is set according to the following rules: If T≤100℃, the spraying time is set to 8 seconds; if 100℃<T≤120℃, the spraying time is set to 12 seconds; if T>120℃, the spraying time is set to 15 seconds. After spraying, monitor the temperature drop rate in real time. When the temperature drop rate is below 0.25℃ / second, repeat the spraying operation once, and reduce the duration of the repeated spraying by 4 seconds.

2. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 1, characterized in that, The target slag volume is generated through the following steps: The propulsion speed signal of the TBM tunneling machine control system is obtained through the MODBUS communication protocol. The current cutterhead cross-sectional area value is retrieved from the TBM equipment parameter library. The propulsion speed signal and the cutterhead cross-sectional area value are input into the multiplier module to calculate the theoretical slag volume. The flow velocity and slag layer height of the slag in the chute are read in real time by the millimeter-wave radar sensor. The flow velocity is divided by the slag layer height to obtain the velocity-height ratio. A database of slag type correspondences is established, which includes a mapping table of velocity-height ratio and density compensation coefficient under different rock strata geological conditions. The mapping table is queried and the corresponding density compensation coefficient is matched in the mapping table according to the current velocity-height ratio. The theoretical slag volume is multiplied by the corresponding density compensation coefficient to generate the target slag volume. When the velocity-height ratio does not match the data in the mapping table, the density compensation coefficient is kept at the preset default value.

3. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 2, characterized in that, When using the soil density compensation coefficient, the following simplified correction process should be performed: After each 10-meter tunneling operation, an offline batch processing correction is performed. The correction operation includes: Retrieve the average actual slag volume Q recorded by the millimeter-wave radar sensor within this 10-meter section. S Based on the average TBM propulsion speed within this 10-meter segment With the cross-sectional area A of the cutter head D Calculate the theoretical average slag volume ; Calculate the slag quantity deviation rate ; If the absolute value of the slag quantity deviation rate δ is greater than 15%, the current density compensation coefficient will be increased or decreased by 0.1δ, the density compensation coefficient in the mapping table will be updated, and a correction log including the deviation rate value and the new coefficient value will be output to the human-computer interaction terminal.

4. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 1, characterized in that, In the operation of real-time acquisition of the flow velocity and slag layer height in the slag chute, the following self-diagnostic method is adopted: A first millimeter-wave radar sensor and a second millimeter-wave radar sensor are symmetrically installed on the slide rails on both sides of the gate. The first flow velocity signal and the first height signal of the first millimeter-wave radar sensor and the second flow velocity signal and the second height signal of the second millimeter-wave radar sensor are acquired synchronously. The signal-to-noise ratio of the first millimeter-wave radar sensor and the signal-to-noise ratio of the second millimeter-wave radar sensor are calculated in real time. If the signal-to-noise ratio of any millimeter-wave radar sensor is lower than 0.5, the millimeter-wave radar sensor is deemed to be faulty; if the first millimeter-wave radar sensor fails, the data from the second millimeter-wave radar sensor is used as the valid signal; if the second millimeter-wave radar sensor fails, the data from the first millimeter-wave radar sensor is used as the valid signal. When both sensors fail, switch to backup control mode: Fix the gate opening to 80% of the previous effective value and send sensor fault code F01 to the human-machine interface terminal; In the operation of acquiring the lateral pressure of the slag and soil borne by the gate in real time, when the pressure value output by the pressure sensor jumps from below 2MPa to above 8MPa within 1 second, the pressure sensor data is marked as invalid, and the average pressure value of the most recent 10 seconds is used as the substitute value.

5. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 1, characterized in that, When the PLC controller detects that the rate of decrease in the flow velocity of the excavated soil exceeds a preset ratio and the pressure value exceeds a preset pressure threshold, it performs the following operations: Start the vibrating motor at the bottom of the slag chute, set the vibration frequency to 20Hz, and simultaneously disable the opening adjustment function of the telescopic cylinder; monitor the change rate of slag flow velocity after the vibrating motor starts in real time, and stop the vibrating motor when the change rate of slag flow velocity exceeds 0.15m / s; Establish a gate operation energy consumption assessment model, record the cumulative stroke of the telescopic cylinder within one hour, and send the telescopic cylinder maintenance warning code E02 to the human-machine interface terminal when the cumulative stroke exceeds 500 times the maximum stroke of the telescopic cylinder; when the TBM tunneling machine enters the step change stop stage, turn off the power supply of the millimeter-wave radar sensor and pressure sensor.

6. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 5, characterized in that, When the vibration motor starts, the following preset vibration strategy is executed: The current rock stratum type code is obtained in real time from the TBM geological prediction system, and preset vibration parameters are matched according to the rock stratum type code. When the rock stratum is coded as mudstone, the vibration frequency is set to 25Hz and the duration is 30 seconds; when the rock stratum is coded as sandstone, the vibration frequency is set to 18Hz and the duration is 20 seconds; when the rock stratum is coded as fault breccia, the vibration frequency is set to 22Hz and the duration is 40 seconds. During the operation of the vibratory motor, the hydraulic pressure value of the telescopic cylinder is monitored in real time. When the hydraulic pressure value exceeds 85% of the system's rated pressure, the vibratory motor is stopped immediately, and the telescopic cylinder is driven to retract to 90% of the gate's maximum opening and maintained for 60 seconds.

7. The method for controlling the gate of the slag chute in an inclined shaft TBM according to claim 1, characterized in that, The operations performed after the audible and visual alarm is triggered include: The system sends a shutdown request signal with the highest priority to the TBM main control system via the CAN bus, continuously records the pressure value output by the pressure sensor, and calculates the pressure change rate per second. When the pressure drops to 60% of the preset safety threshold, the first stage of recovery is executed: the telescopic cylinder is driven to retract to 80% of its maximum opening and maintained at that opening for 120 seconds. The system monitors the slag flow velocity signal output by the millimeter-wave radar sensor in real time. When the slag flow velocity recovers to 70% of the velocity before the blockage is triggered and the pressure fluctuation range is stable within ±15% of the preset pressure threshold, the second stage of recovery is executed: the gate opening is gradually increased at a rate of 5% per second until the opening required to match the real-time slag volume with the target slag volume is reached; when the pressure rise exceeds 0.5MPa per second during the opening adjustment process, the opening increase is paused and the current state is maintained for 60 seconds; when the gate opening is stable and the pressure value does not exceed 80% of the preset pressure threshold for 300 seconds, the audible and visual alarm is deactivated.

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