Method and system for monitoring real-time data of shield tunneling machine and improving operation efficiency

Abstract

The invention provides a shield tunneling machine real-time data monitoring and operation efficiency improving method and system, and relates to the field of industrial equipment intelligent monitoring and optimal control. Multifunctional sensor modules are arranged on a cutter head system, a propelling system, a soil bin system and a shield tail system of a shield tunneling machine to collect operation parameters; and the local data processing unit is used for filtering and checking the data, so that the accuracy and reliability of the data are ensured. Based on a geological survey report, geological conditions are divided into multiple stratums, differential monitoring parameter combinations for different stratums are constructed, and dynamic monitoring and adjustment are achieved. And a tunneling speed optimization model based on the stratum discrimination function is further established, and the optimal tunneling speed is calculated in real time according to the dynamic change of the stratum characteristics, so that the tunneling efficiency of the shield tunneling machine is remarkably improved, the construction uncertainty is reduced, and the construction safety is improved.

Description

Technical Field

[0001] The present invention relates to the field of intelligent monitoring and optimization control of industrial equipment, and more specifically, to a method and system for real-time data monitoring and operation efficiency improvement of a shield machine. Background Art

[0002] As the core equipment in tunneling projects, the technological development of shield machines has been continuously improved along with the growing demand of the tunnel construction industry and the gradual increase in the complexity of geological conditions. Early shield machines were mostly mechanical, with relatively simple technology, but they had many limitations in terms of adaptability to rock and soil layers, excavation efficiency and construction safety. With the rapid development of hydraulic technology, sensor technology, automatic control technology and data processing technology, modern shield machines are gradually developing in the direction of intelligence, multi-function and efficiency. Especially driven by the demand for construction under complex geological conditions, key technologies such as the cutter head design, propulsion system control, soil bin pressure monitoring and shield tail sealing performance optimization of shield machines have been significantly improved. However, although the current shield machines have made great progress in excavation efficiency and construction safety, they still face many challenges, especially in real-time data monitoring and parameter control, and have not yet fully realized efficient and accurate intelligent control.

[0003] In the existing technology, the real-time data monitoring and analysis of shield machines mainly rely on the distributed sensor layout and a single data acquisition system. However, this technical solution has certain deficiencies in the comprehensiveness and accuracy of data acquisition. On the one hand, the existing sensor layout is usually aimed at a single system (such as the cutterhead system or propulsion system), and fails to achieve the coordinated monitoring of multiple systems such as the cutterhead system, propulsion system, soil bin system and shield tail system, resulting in insufficient correlation analysis between key parameters; on the other hand, the processing capacity of the data acquisition backend is limited, and the geological condition information in the geological survey report cannot be fully utilized to intelligently control the excavation parameters, especially under complex stratum conditions such as geological transition zones. The existing technology cannot achieve dynamic and accurate monitoring and optimization of excavation parameters. In addition, the existing storage and backup mechanisms usually fail to effectively manage the timeliness and importance of data, and there is a risk of data redundancy or loss of key data, which further restricts the operating efficiency and construction safety of the shield machine. Summary of the invention

[0004] In order to solve the above technical problems, the present invention is proposed. The present invention provides a method and system for real-time data monitoring and operation efficiency improvement of a shield machine.

[0005] According to one aspect of the present invention, a method for real-time data monitoring and operation efficiency improvement of a shield machine is provided, which comprises: Arrange multifunctional sensor modules in the cutterhead system, propulsion system, soil bin system and shield tail system of the shield machine to collect operating parameters; process data through the local data processing unit to generate geological survey reports; Based on the geological survey report, the geological conditions are divided and differentiated monitoring parameter combinations are set for different geological conditions; when in the geological transition zone, the monitoring schemes of adjacent geological types are activated at the same time; Based on different geological conditions, a tunneling speed optimization model based on the stratum discriminant function is established. Through the combined effect of differentiated monitoring parameters under different geological conditions, intelligent regulation of tunneling parameters is realized; the optimal tunneling speed is calculated according to the dynamic changes of stratum characteristics.

[0006] Further, based on the geological survey report, the geological conditions are divided into soft soil layer, sand and gravel layer, weathered rock layer, intact rock layer and composite layer; The composite strata include: a soft soil-sand and gravel composite layer, a sand and gravel-weathered rock composite layer, a soft soil-weathered rock composite layer, a weathered rock-intact rock composite layer and a soft soil-sand and gravel-weathered rock composite layer.

[0007] Furthermore, in the soft soil-sand-pebble composite layer, when entering the transition zone, the formation conversion is judged by the pressure distribution and groundwater changes, and corresponding adjustment strategies are adopted according to the torque change mode, including: When the torque changes in a step-by-step manner, the cutter head speed is gradually increased, the propulsion speed is reduced, and the soil pressure and filling amount are dynamically adjusted; When the torque changes in a fluctuating manner, optimize the cutting parameters and adjust the soil pressure and grouting parameters in advance; As torque changes gradually increase, smoothly adjust propel speed and earth pressure control.

[0008] Furthermore, in the sand-pebble-weathered rock composite layer, when the layer enters the weathered rock transition, different strategies are adopted according to the torque change mode, including: When the torque changes continuously increase, it indicates that the weak weathering zone has been entered. The advancement speed is reduced, the soil pressure is gradually adjusted to the support mode, and the shield tail system increases the slurry strength; When the torque changes in a fluctuating upward manner, it indicates that the broken weathering zone has been entered. Real-time collection of parameters is used to establish the corresponding relationship between geological conditions and construction parameters, and to optimize the ratio of cutter head speed and propulsion speed. When the torque changes suddenly and rises, it indicates that hard rock or strongly weathered rock is encountered. Reduce the propulsion speed, adjust the cutter head speed, and temporarily increase the slurry strength.

[0009] Furthermore, in the soft soil-weathered rock composite layer, when entering the transition zone, the construction parameters are adjusted according to the torque change, and dynamic control is performed in combination with the groundwater conditions, including: When the torque changes continuously and gradually, it indicates that the transition zone between soft soil and rock mass has been entered. The soil bin pressure is adjusted to form a pressure gradient, and the propulsion speed is gradually reduced while observing the torque changes. When the torque changes in a fluctuating and increasing manner, it indicates that there are soft and hard interlayers in the transition zone. In the soft layer section, soil pressure is mainly controlled, the cutter head speed is increased and the advancement speed is reduced; in the hard layer section, the cutting parameters are optimized, the advancement speed is reduced first and then the speed is adjusted; When the torque changes in a step-by-step manner, it indicates that the rock strength increases in a step-by-step manner. Immediately reduce the advancement speed, maintain the stability of the excavation face, and adjust the advancement speed and cutter head speed according to the properties of the interlayer.

[0010] Furthermore, in the weathered rock-intact rock composite layer, when the layer transitions to intact rock, different strategies are adopted according to the torque change mode, including: When the torque changes evenly, it indicates that it has entered the slightly weathered transition zone. Keep the cutter head speed stable, adjust the propulsion speed to adapt to the change in rock strength, and optimize the slurry ratio of the shield tail system. When the torque changes in a pulsed manner, it indicates the existence of interlayered lithologies. The corresponding relationship between torque changes and lithology conversion is established, and the cutting parameters are adjusted dynamically to quickly respond to different lithology characteristics. When the torque changes suddenly, it indicates entering a hard rock section. The cutter head rotation speed and propulsion speed should be adjusted quickly to strengthen rock support.

[0011] Furthermore, based on the different geological conditions, the stratigraphic characteristic parameters are extracted through principal component analysis, which are multiplied by the corresponding weight coefficients. The sensitivity coefficients are introduced to control the rate of change of the stratigraphic transition zone. The distance between the excavation position and the starting point of the transition zone is dynamically adjusted to establish a stratigraphic classification discriminant function.

[0012] Furthermore, based on the stratum classification discriminant function, the current geological conditions are determined, and based on different geological conditions, the influencing factors of the excavation speed are further determined, and the reference speed is combined with the influencing factors to obtain the optimal excavation speed under different geological conditions.

[0013] Furthermore, the calculation of the optimal excavation speed also includes a formation adaptability coefficient, a strength correction index, a pressure sensitivity coefficient and a torque correction coefficient; The formation adaptability coefficient increases gradually from soft soil to intact rock according to the formation type; The strength correction index reflects the influence of formation strength through normalization and linear interpolation; The pressure sensitivity coefficient adopts an inverse relationship to describe the importance of soil layer pressure and decreases as the strength of the formation increases; The torque correction coefficient adopts a proportional relationship and reflects the limiting effect of the cutter head torque on the excavation speed through normalized calculation.

[0014] According to another aspect of the present invention, a method for real-time data monitoring and operation efficiency improvement of a shield machine is provided, comprising: The data processing module is used to collect the operating parameters of each system of the shield machine in real time; the data is processed through the local data processing unit to generate a geological survey report; The differentiated monitoring module is used to divide geological conditions according to geological survey reports and set differentiated monitoring parameter combinations for different geological conditions; The optimization module is used to establish an optimization model for tunneling speed based on the formation discriminant function, realize intelligent regulation of tunneling parameters through the combined effect of differentiated monitoring parameters under different geological conditions, and calculate the optimal tunneling speed according to the dynamic changes of formation characteristics.

[0015] Compared with the existing technology, the present invention realizes accurate calculation and real-time adjustment of tunneling speed by distinguishing different geological conditions and classifying them, adapting to different complex strata, improving the adaptability of tunneling equipment, ensuring equipment safety and stratum stability, optimizing speed, reducing energy consumption and tool wear, and improving efficiency. Overall, it solves the problems of poor adaptability, insufficient precision and low efficiency of the existing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 The present invention is a flowchart of a method for real-time data monitoring and operation efficiency improvement of a shield machine according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] Below, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described here.

[0018] As mentioned in the above background technology, the prior art mainly has the following two prominent problems: First, the excavation speed control lacks adaptability to complex strata, and the excavation speed cannot be dynamically adjusted according to different stratum conditions (such as soft soil, sand and gravel, weathered rock, etc.), resulting in low excavation efficiency; second, the impact on key stratum parameters (such as stratum strength, soil bin pressure, cutter head torque, etc.) has not been effectively quantified, and it is easy to have excessive equipment loss or unstable excavation during the excavation process. In response to these technical pain points, our invention proposes an optimal excavation speed calculation method based on stratum classification discriminant function and dynamic correction coefficient. The present invention introduces the stratum classification discriminant function, combines the stratum adaptability coefficient, strength correction index, pressure sensitivity coefficient and torque correction coefficient, comprehensively considers the influence of different stratum conditions on the excavation speed, dynamically adjusts the excavation speed, improves the stratum adaptability and calculation accuracy, and ensures equipment safety and stratum stability, thereby effectively solving the problems of poor adaptability, insufficient accuracy and low efficiency in the prior art, and belongs to the intelligent control method in the field of excavation technology.

[0019] Figure 1 Flow chart of a method for real-time data monitoring and operation efficiency improvement of a shield machine according to an embodiment of the present invention. Figure 1 As shown, the shield machine real-time data monitoring and operation efficiency improvement method includes: S1: Multifunctional sensor modules are arranged in the cutterhead system, propulsion system, soil bin system and shield tail system of the shield machine to collect operating parameters; data is filtered and verified through the local data processing unit; a hierarchical storage strategy is used to manage data and generate a geological survey report.

[0020] As the core execution unit of shield tunneling, the cutterhead system is equipped with all-round monitoring, including: installing a high-precision torque sensor at the main drive motor to monitor the change of cutterhead torque in real time, with a sampling frequency of 100Hz to ensure that the torque mutation can be captured in time; installing a multi-point distributed speed sensor on the cutterhead body to monitor the uniformity of the cutterhead rotation, and setting a temperature sensor array at the drive gearbox to monitor the temperature distribution of the transmission system. At the tool installation position, each tool holder is equipped with a three-way strain sensor to monitor the force direction and size of the tool. The tool wear detection adopts a laser ranging and inductive dual detection solution to ensure the accuracy of the wear data. An array of earth pressure sensors is arranged in the contact area between the cutterhead and the soil to monitor the pressure distribution of the excavation surface.

[0021] The propulsion system is responsible for the forward power of the shield machine and has a complete monitoring system, including: installing high-precision pressure sensors on the main propulsion cylinders to monitor propulsion pressure, with a sampling frequency of 50Hz; each cylinder is equipped with a displacement sensor to accurately control the propulsion stroke; high-precision gyroscopes and inclination sensors are set up in front and behind the shield machine to monitor posture changes in real time. A flow sensor and temperature sensor network are set up on the hydraulic circuit of the main propulsion system to monitor system flow distribution and temperature changes. Pressure and displacement sensors are installed at the articulated cylinders to monitor steering process parameters.

[0022] The soil bin system is the key to the control of slag soil. It adopts diversified monitoring, including: arranging pressure sensor arrays along the circumference and axial direction in the soil bin to form a pressure distribution cloud map; setting up multi-point mud-water interface sensors to accurately monitor the position changes of the mud-water interface; installing high-precision moisture content sensors and density sensors at the inlet and outlet to monitor the physical properties of the slag soil. The screw conveyor is equipped with a torque sensor and a speed sensor, combined with motor current monitoring, to fully grasp the soil discharge working conditions. A sediment detection device is set at the bottom of the soil bin to monitor the slag soil deposition.

[0023] The shield tail system is an important area for segment installation and grouting. High-precision electromagnetic flowmeters and pressure sensors are installed on the grouting pipeline to monitor grouting parameters in real time. Each grouting hole is equipped with independent pressure monitoring to ensure grouting uniformity. A pressure sensor array is arranged at the sealing ring to monitor the sealing pressure distribution. A laser ranging system is set up in the segment assembly area, and the angle sensor is used to ensure the segment assembly accuracy, with a displacement accuracy of up to 0.1mm.

[0024] All sensors adopt IP67 protection grade or above, with waterproof, dustproof, shockproof, anti-electromagnetic interference and other functions, and the operating temperature range is -20℃ to 70℃. Key sensors adopt dual backup design. A hierarchical sampling strategy is adopted according to the importance of parameters: the core parameters, namely the sensor parameters of the cutter head torque and soil bin pressure, adopt high-frequency sampling of 50-100Hz, and the general parameters adopt conventional sampling of 1-10Hz. The historical trend data adopts a variable sampling rate storage strategy to optimize the use of storage space.

[0025] The sensor network adopts a bus-star hybrid topology, and achieves high-speed data transmission through industrial Ethernet. The fieldbus adopts the Profibus-DP protocol with redundancy to ensure communication reliability. A local data cache mechanism is set up to ensure data integrity when communication is interrupted. All sensors have online calibration functions and are automatically calibrated regularly to ensure long-term accuracy.

[0026] Furthermore, the collected data is transmitted to the local data processing unit for real-time data filtering and verification. The data processing adopts a hierarchical processing strategy: The first layer is sensor-level data preprocessing, which performs anti-interference processing on the raw data, including electrical noise filtering, signal stability verification and value range checking, to eliminate abnormal data caused by electromagnetic interference, mechanical vibration, etc. Including: using a low-pass filter to filter electrical noise, the cutoff frequency is dynamically adjusted according to the signal characteristics, and the typical value is 1 / 10 of the sampling frequency; signal stability verification calculates the variance in a short-time window, and when the variance exceeds the preset threshold, it is marked as an unstable signal; the value range check sets the upper and lower limits based on the sensor range and physical limits, and sets a dynamic limit interval of ±20% for the cutter torque signal. Through independent electromagnetic shielding design and anti-interference grounding measures, the impact of external interference is reduced from the hardware level. For interference caused by mechanical vibration, vibration reduction mounts and signal smoothing algorithms are used to suppress it to ensure the basic quality of the signal.

[0027] The second layer is parameter-level data processing, which uses specific filtering algorithms for different types of parameters. Core parameters such as cutter head torque data use bandpass filtering to eliminate high-frequency vibration and low-frequency drift, soil pressure data use median filtering to remove outliers, and displacement data use Kalman filtering to improve accuracy. Specifically, the cutter head torque data uses a bandpass filter, and the passband range is determined to be 0.1-10Hz through frequency analysis, which effectively eliminates high-frequency mechanical vibration and low-frequency zero drift, while retaining effective information on torque changes; the soil pressure data uses an 11-point median filtering algorithm, combined with the 3σ criterion to identify and eliminate outliers. For rapidly changing pressure signals, a median filter with an adaptive window size is used to balance the response speed and filtering effect; the displacement data is processed by a Kalman filter, and the true displacement value is estimated in real time through the state equation and observation equation based on the noise characteristics of the displacement sensor. The process noise covariance and observation noise covariance are determined through on-site calibration.

[0028] The third layer is system-level data verification, which is cross-validated through logical relationships and physical constraints between parameters, such as the correlation test between thrust pressure and cutter disc torque, and the verification of the balance relationship between soil bin pressure and soil discharge volume.

[0029] Data verification uses multiple mechanisms: real-time verification judges the validity of data, including value range check, change rate limit and data integrity verification; regular verification verifies data accuracy through sensor self-test and calibration device, core sensors perform automatic calibration every 4 hours, and general sensors are calibrated every 24 hours; system verification verifies the integrity through redundant sensor data comparison and system status analysis to ensure data reliability. When data anomalies are detected, it automatically switches to the backup channel and records the anomaly information for subsequent analysis.

[0030] The hierarchical storage strategy includes: real-time control data is stored in a high-speed cache, using memory database technology to achieve millisecond-level data access, the cache capacity supports 24-hour high-frequency data storage, and a data snapshot mechanism is set up to record complete data at critical moments; process optimization data is stored in a time series database, supporting efficient time series analysis and data compression, archiving data on an hourly basis, and keeping complete records for 30 days; status assessment data is stored in a relational database to achieve data correlation analysis and long-term traceability, and archiving and saving full-cycle data on a daily basis.

[0031] The setting of backup acquisition channels follows the principle of redundant design: core parameters use dual backup solutions, and complementary measurements are achieved through different types of sensors, such as soil pressure monitoring using pressure sensors and soil pressure gauges at the same time; key parameters use the same type of backup solution, and reliability is ensured by arranging the same type of sensors in parallel; general parameters are indirectly backed up through system status parameters, and data verification is achieved by using the correlation between parameters. The data of the backup channel is independently collected and stored, and the data quality is evaluated in real time through the data comparison algorithm, and it automatically switches when the data of the main channel is abnormal.

[0032] The data management system implements a multi-level backup strategy: local storage uses disk array technology to achieve data redundancy through RAID5; remote backup is synchronized to the backup server at the construction site in real time through a dedicated network; cloud archiving uses encrypted transmission to upload key data to the cloud storage platform regularly. A data recovery mechanism is set up to support selective recovery by time point and data type to ensure data reliability and availability.

[0033] Metadata management runs through the entire data processing and storage process: each data record contains complete metadata tags, recording information such as data collection time, sensor status, processing level, quality grade, etc.; the system maintains a metadata dictionary to define the physical meaning of data items, unit conversion, alarm threshold and other attributes; metadata indexing is used to achieve rapid retrieval and association analysis of data.

[0034] Through multi-level data processing, the accuracy, completeness and availability of data are ensured, providing a reliable data basis for shield construction process control.

[0035] S2: Based on the geological survey report, the geological conditions are divided into multiple strata, and differentiated monitoring parameter combinations are set for different geological conditions; when in the geological transition zone, the monitoring schemes of adjacent geological types are activated at the same time.

[0036] According to the geological survey report, the geological conditions are divided into soft soil layer, sand and gravel layer, weathered rock layer, intact rock layer and composite layer; The composite strata include: soft soil-sand and gravel composite layer, sand and gravel-weathered rock composite layer, soft soil-weathered rock composite layer, weathered rock-intact rock composite layer and soft soil-sand and gravel-weathered rock composite layer.

[0037] Different controls are carried out according to different geological conditions, including: In a typical saturated soft soil layer, deformation control and groundwater balance are the core. The excavation surface is divided into three pressure control areas: upper, middle and lower. The pressure distribution should be kept uniform, and the upper pressure is slightly higher than the lower pressure to prevent surface subsidence. If the pressure in the middle area rises abnormally, the amount of replenishment in this area should be reduced, and the opening of the discharge gate should be appropriately increased to speed up the discharge. When the pressure in the lower area fluctuates, the discharge rate should be adjusted first. When the pressure continues to rise and the amount of replenishment needs to be reduced, the parameters of the middle and upper areas should be adjusted synchronously to maintain the pressure distribution shape. The pore water pressure distribution is monitored in real time through an array of water pressure monitoring points to ensure that the soil bin pressure is always 0.1-0.2MPa higher than the water pressure.

[0038] The cutterhead system adopts a low-torque configuration, and the ratio of the cutterhead speed to the propulsion speed is maintained in the range of 1:3 to 1:4. When the soil pressure distribution is locally abnormal, the propulsion speed should be appropriately reduced to keep the cutterhead speed stable, and the propulsion speed should be gradually restored after the pressure is re-balanced. If the moisture content of the soil is found to be increased, the cutterhead speed should be reduced while maintaining the pressure of the excavation surface stable, the cutting time per unit of soil should be extended, and the screw conveyor speed should be adjusted to control the soil discharge rate. During the adjustment process, focus on monitoring the torque change trend. When the torque fluctuates, the soil state change should be analyzed, and the matching relationship between the propulsion speed and the cutterhead speed should be adjusted if necessary.

[0039] The slurry ratio should be high-fluidity, and the slurry strength should match the soil strength. When the pressure in a certain section is continuously low, the grouting pressure and grouting volume of the section should be increased first. The grouting pressure should be increased in a step-by-step manner, and the soil pressure response should be observed after each increase. At the same time, the grouting pressure monitoring frequency should be increased to analyze the pressure transmission effect. If the synchronous grouting effect in a certain section is not good, advance grouting or supplementary grouting should be enabled, and the grouting point layout should be adjusted to ensure that the slurry is fully diffused.

[0040] In homogeneous sand and gravel layers, the key is to prevent collapse and sand surge. When the pressure on the excavation surface fluctuates rapidly, first lock the fluctuation area and analyze its diffusion trend. For local high-pressure areas, adjust the speed of the soil discharge screw to quickly reduce the pressure and reduce the amount of replenishment in this area. When the pressure continues to drop, use the rapid replenishment method to increase the amount of replenishment by increasing the opening of the feed valve and reduce the soil discharge rate. During the adjustment process, closely monitor the pressure changes in the surrounding area to prevent the spread of pressure fluctuations.

[0041] Further adjust the cutting parameters. When the torque fluctuates and the soil pressure is relatively stable, it indicates that the local density has changed. At this time, adjust the cutter head speed and the propulsion speed accordingly to maintain a suitable cutting ratio. If the soil moisture content is abnormal, it is necessary to adjust the opening frequency and control the single opening time to prevent sand gushing. During the adjustment process, continuously monitor the force state of the tool and adjust the excavation posture in time when the force is uneven.

[0042] During the grouting process, pay special attention to the water-stopping effect. When the groundwater pressure in a certain section is found to be abnormal, increase the grouting pressure in that section and increase the grouting volume. The adjustment of grouting pressure needs to maintain a dynamic balance with the soil bin pressure and water pressure to avoid pressure backflow. If necessary, enable secondary supplementary grouting or change the grouting material ratio to enhance the water-stopping effect.

[0043] In weathered rock formations, the main goal of earth pressure control is to prevent collapse and rock blocks from falling. A multi-level pressure monitoring network is established to track the pressure distribution of the excavation surface in real time. When there is a sudden change in the advancement resistance, the advancement speed is first reduced by 20%-30%, while the cutter head speed is kept stable, and the degree of rock weathering is comprehensively evaluated through rock slag particle analysis and drilling data. If stress concentration is detected in a certain area, it indicates that there is a significant difference in the degree of weathering there. At this time, the excavation posture needs to be adjusted to make the cutting surface adapt to the occurrence of the rock formation. When excavating in a joint-developed zone, the support pressure is increased to 1.2-1.5 times the normal value, and the monitoring frequency is increased, and the support parameters are adjusted at any time.

[0044] The adjustment strategy of the cutterhead system needs to be dynamically optimized according to the degree of weathering. When the torque continues to rise and exceeds the set threshold, the propulsion speed is preferentially reduced by 15%-25% to keep the cutting thickness within a reasonable range. If the mechanical vibration intensifies, the optimal cutting frequency is found by gradually adjusting the cutterhead speed, and the adjustment amplitude is controlled within 10% each time. In this process, the pressure distribution of each soil bin is monitored to keep the pressure fluctuation amplitude within the allowable range.

[0045] The grouting pressure should be adjusted according to the degree of rock weathering and the degree of crack development, and controlled at 1.1-1.3 times the soil bin pressure. In the crack development zone, the "multiple-stage" grouting strategy is adopted, that is, low-pressure rapid grouting is first used to form the initial support, and then high-pressure supplementary grouting is used to strengthen the support effect. The selection of grouting materials should take into account the permeability and strength requirements, and the water-cement ratio and admixture ratio should be adjusted according to the crack characteristics.

[0046] Earth pressure control in intact rock formations is used to maintain the stability of the excavation face and protect the cutter. The rock properties are judged by the change law of the advancing resistance. When the rock strength changes, the support pressure is adjusted accordingly, but the pressure value is maintained at a low level. In the joint development zone, the support pressure also needs to be increased, but the increase is usually only 1.1-1.2 times the original pressure. Continuously analyze the change trend of the advancing resistance, establish the corresponding relationship between the rock strength and the support pressure, and realize the precise control of the support parameters.

[0047] The adjustment of the cutter head system focuses on protecting the tool and improving efficiency. When the torque continues to rise and exceeds the warning value, the "adjustment of propulsion speed first" strategy is adopted, that is, the propulsion speed is first reduced by 10%-20%, the cutter head speed is kept unchanged, and the torque change trend is observed. If the vibration intensifies, the ratio between the cutter head speed and the propulsion speed is optimized. During the entire adjustment process, the tool stress state is monitored, including tool temperature, wear degree, etc. When an abnormality occurs, the early warning mechanism is activated and the cutting parameters are adjusted in time.

[0048] The shield tail system mainly considers the support and reinforcement effect. The grouting pressure is maintained at a low level, mainly to ensure the filling density. The selection of grouting materials is based on the principle of strength matching, and the grouting strength is required to be slightly higher than the rock mass strength. In the joint zone, the support effect is ensured by changing the grouting parameters and grouting methods, such as layered grouting or annular grouting.

[0049] All parameter adjustments are based on continuous monitoring and data analysis to achieve precise control. At the same time, the accumulated construction data and control experience continuously optimize the control strategy and improve construction safety and efficiency.

[0050] When shield construction is carried out under complex strata conditions, it is necessary to accurately identify and dynamically respond to strata changes. Comprehensively process the changing characteristics of core parameters such as cutter head torque, propulsion resistance and soil bin pressure.

[0051] Furthermore, in the soft soil-sand and gravel composite layer, in the soft soil section, the control strategy refers to the single soft soil layer. When the formation begins to change, the pressure distribution characteristics are first used for prediction. When the earth pressure sensor array detects that the pressure distribution changes from uniform to uneven, and the ratio of the upper pressure to the lower pressure begins to increase, it indicates that it is entering the sand and gravel transition zone. At the same time, the change of groundwater conditions also provides an important basis for judging the formation conversion. At this time, the focus is on the torque change characteristics, and three typical change modes appear: step-by-step rise, fluctuating rise, or gradual rise.

[0052] When a step-like rising feature appears, it indicates that it is about to enter a large-grained sand and gravel enrichment area. Start the "small step fast adjustment" strategy: increase the cutter head speed by 5%-10% each time, observe the torque stability, and make the next adjustment after confirming that the torque is stable again. At the same time, the propulsion speed needs to be reduced synchronously, and the reduction range is 1.2-1.5 times the speed increase to ensure that the cutting parameters match. The soil pressure control is switched to dynamic adjustment mode, and the replenishment amount is adjusted by region according to the pressure distribution change trend. Special attention should be paid to the influence of pressurized water that may exist between the large-grained sand and gravel layers. Once a pressurized water layer is found, the soil pressure in this section should be increased immediately. The shield tail system begins to increase the slurry strength and increase the grouting points as needed to prevent water and soil from colluding and causing construction risks.

[0053] If the fluctuating rising characteristics are monitored, it means that the loose sand and gravel area has been entered. At this time, the permeability increases significantly, and water pressure control becomes the key. Adopt a "steady and gradual" strategy: the cutter head speed is increased by 3%-5% each time, focusing on analyzing the torque fluctuation cycle, and continuing to optimize the parameters when the fluctuation shows regularity. The adjustment of the propulsion speed must be coordinated with the speed change, and the cutting parameter combination is optimized by continuously monitoring the soil crushing state. By analyzing the water pressure change law in real time, the soil bin pressure and grouting parameters can be adjusted in advance.

[0054] When a progressive rise feature is detected, it indicates that the transition zone is wide. The advancement speed is gradually adjusted according to a gentler curve, and the parameter matching is continuously evaluated and the control strategy is dynamically optimized. A gradual adjustment mechanism is established for soil pressure control, and the grouting parameters are gradually optimized as the stratum changes, ensuring smooth and controllable construction of the transition zone.

[0055] After entering the gravel section completely, the control strategy refers to a single gravel layer. By analyzing the gravel grading and hardness distribution characteristics, the zone pressure control target is preset and precise replenishment control is implemented. The groundwater control is switched to active pre-control mode, and a zone control strategy is established by analyzing the groundwater flow direction and pressure distribution. In sections prone to water inrush, the soil bin pressure is appropriately increased, and grouting protection is strengthened. The cutter disc system optimizes the cutter disc speed and propulsion speed ratio according to the characteristics of gravel and establishes a cutter protection mechanism.

[0056] During the entire transition process, the changes in various parameters are continuously monitored. When the soil pressure fluctuates rapidly, the parameters are immediately adjusted to restore the balance; when the torque change is found to be beyond expectations, the cutting parameter combination is optimized in a timely manner; when the local water pressure is monitored to be abnormally high, the soil bin pressure in the area needs to be quickly increased, and the drainage efforts need to be increased; if the grouting effect decreases, the grouting pressure is adjusted or the grouting position is changed.

[0057] Furthermore, in the gravel-weathered rock composite layer, in the gravel section, a comprehensive control system with earth pressure balance and groundwater control as the core is established. Earth pressure control monitors the pressure distribution of the excavation surface through multi-point pressure sensors, and at the same time, an array of water pressure monitoring points is arranged to track the groundwater status in real time. The cutterhead system adopts a higher speed configuration. The ratio of the cutterhead speed to the propulsion speed is determined according to the gravel grading characteristics, and the force state of the tool and the torque change trend are continuously monitored. The shield tail system uses a quick-setting ratio, and the grouting pressure maintains a dynamic balance with the soil bin pressure and water pressure to ensure the filling effect and water-stopping effect.

[0058] When the strata begin to transition to weathered rock, the torque changes will show three typical characteristic combinations: continuous rise, fluctuating rise or sudden rise. At the same time, the state of groundwater will also change significantly, gradually changing from pore water to fissure water.

[0059] When the continuous rising characteristics appear, it indicates that it has entered the weak weathering zone. Start the "gradual transition" strategy: maintain the cutter head speed basically stable, gradually reduce the propulsion speed, and observe the torque change trend in each adjustment cycle. The earth pressure control system is gradually adjusted to the support pressure mode, the shield tail system increases the slurry strength, and the grouting parameters are determined by monitoring the fracture water pressure.

[0060] If the fluctuating rising characteristics are monitored, it means that the broken weathering zone has been entered. At this time, the "coordinated control" strategy is adopted: by continuously collecting basic parameters such as real-time torque value, propulsion pressure, propulsion speed, and cutterhead speed during the excavation process, while recording auxiliary parameters such as earth pressure distribution, soil discharge parameters, and grouting pressure, and marking geological change nodes, the corresponding relationship between parameters and geological conditions is established. In the data analysis stage, by establishing the change trend curve of torque and propulsion resistance, analyzing the temporal relationship between the changes of the two, determining the corresponding laws of key inflection points and mutation points, and finally forming a parameter change feature library under different geological conditions, the optimal cutterhead speed and propulsion speed are determined based on historical data to optimize the cutterhead speed and propulsion speed ratio. Earth pressure control turns to active support mode, and pressure control pays more attention to the stability of the excavation face. Due to the development of fissure water at this time, it is necessary to strengthen advance detection and adjust the grouting plan in time to prevent sudden surges.

[0061] When a sudden rise is detected, it indicates that hard rock or strongly weathered rock is encountered. The "quick response" strategy is initiated: the propulsion speed is quickly reduced, the cutter head speed is adjusted according to the torque change characteristics, and the cutting posture is adjusted by a short stop when necessary. The shield tail system temporarily increases the slurry strength to enhance the filling effect of the broken zone. At the same time, the development of local rock mass cracks is closely monitored.

[0062] Specifically, the strength characteristics of hard rock blocks are judged by the torque mutation amplitude. The larger the torque mutation value, the higher the rock strength. At the same time, the torque rise rate is analyzed. A rapid and steep rise usually means encountering a whole hard rock block, while a step-by-step rise indicates the presence of a broken hard rock mass.

[0063] After confirming that hard rock is encountered, the rapid deceleration mechanism is immediately activated. The initial speed adjustment adopts a large speed reduction strategy, reducing it to 60-70% of the normal working speed. This initial speed reduction value is a safe speed range determined based on a lot of engineering experience. The speed reduction process must be completed within 1-2 minutes to avoid excessive wear of the tool. After completing the initial speed reduction, enter the fine adjustment stage.

[0064] In the fine adjustment stage, first observe the torque response characteristics after speed reduction. If the torque drops significantly but remains at a high level, it indicates that the initial speed reduction is basically reasonable and needs to be fine-tuned and optimized. If the torque drop is not obvious, the speed needs to be further reduced; if the torque drop is too large, the speed should be appropriately increased. The fine-tuning amplitude is controlled between 5-10% each time, and the torque change trend is observed for 2-3 minutes after each adjustment.

[0065] During the speed adjustment process, the cutting specific energy index is focused on, which reflects the relationship between tunneling efficiency and energy consumption. The speed is continuously fine-tuned until the cutting specific energy reaches the optimal range. The optimal range is reflected in: on the premise of ensuring safe tunneling, it can maintain a high tunneling efficiency and control energy consumption within a reasonable range.

[0066] At the same time, a linkage adjustment mechanism between the rotation speed and the propulsion speed is established. After the optimal rotation speed is determined, the propulsion speed is adjusted accordingly to achieve the best match between the two. When the cutter head rotation speed decreases, the propulsion speed also needs to be reduced accordingly, but the reduction ratio needs to be determined based on the actual torque response characteristics.

[0067] During the speed adjustment process, it is necessary to continuously monitor the stress state of the cutter. If the local cutter stress is abnormal, fine-tune the speed in time. At the same time, pay attention to the rock crushing characteristics of the excavation surface. When local crushing intensifies, increase the speed appropriately to improve the crushing effect. For possible hard interlayers, establish a speed adjustment plan in advance to ensure a quick response of the system.

[0068] After entering the weathered rock section, the control strategy shifts to rock mass property control. The excavation surface is divided into multiple control areas, and precise filling control is implemented. Groundwater control is switched to the fissure water-dominated mode, and a regional control strategy is established. In sections prone to water inrush, the soil bin pressure is appropriately increased and grouting protection is strengthened. The cutterhead system continuously optimizes the cutterhead speed and propulsion speed ratio according to the rock mass characteristics to ensure a balance between excavation efficiency and tool protection.

[0069] Furthermore, in the soft soil-weathered rock composite layer, in the soft soil section, the control strategy refers to the single soft soil layer. When the transition from the stratum to the weathered rock is monitored, the typical change characteristics are also identified: continuous increase, fluctuation increase or step increase. The transition zone is often accompanied by significant changes in groundwater conditions and requires special attention.

[0070] When the continuous increasing characteristics appear, it indicates that the soft soil-rock transition zone has been entered. The "pressure priority" strategy is adopted: first adjust the soil pressure distribution, monitor the pressure change trend in different areas of the excavation surface through the pressure sensor array, and determine the boundary position between the soft soil area and the rock area in combination with geological forecast information. Maintain a higher soil bin pressure in the soft soil area to prevent collapse, and appropriately reduce the pressure in the rock area to avoid excessive squeezing, so as to form a pressure gradient distribution that conforms to the characteristics of the formation. According to the stability of the soil pressure after adjustment, the cutter head speed and propulsion speed are matched and adjusted.

[0071] The parameter ratio adjustment adopts a progressive strategy. First, under the premise of keeping the total cutting power relatively stable, the advancement speed is reduced to reduce the instantaneous contact stress between the tool and the rock mass.

[0072] If the torque continues to rise after the propulsion speed is reduced, continue to reduce the propulsion speed by a larger amount than the previous adjustment until the torque growth trend slows down.

[0073] If the propulsion resistance begins to stabilize, maintain the propulsion speed and gradually increase the cutter head speed. Each time the speed is increased, a small increase should be made to observe the torque change trend.

[0074] If the torque drops significantly after increasing the cutter head speed, it means that the rock crushing effect has improved and the speed can be increased slightly; if the torque fluctuation intensifies, the speed should be appropriately reduced to the level before the fluctuation occurs.

[0075] If abnormal fluctuations in soil pressure are found at the junction of the soft soil area and the rock area during the adjustment process, the speed adjustment will be suspended, and the replenishment volume and soil discharge rate in this area will be adjusted first. Parameter adjustment will be continued after the pressure stabilizes again.

[0076] If a sudden change in torque occurs in a local area, the corresponding pressure distribution in that area shall be analyzed immediately, and local pressure regulation shall be adopted as a priority to return the torque to normal levels by adjusting the replenishment volume and soil discharge parameters in that area.

[0077] If the indicators tend to be stable after parameter adjustment, the current parameter combination will be recorded as the benchmark parameter under the geological conditions to guide subsequent excavation.

[0078] After the propulsion resistance becomes stable, gradually increase the cutter head speed to increase the rock crushing effect. Determine the optimal speed increase by observing the torque change response.

[0079] When the fluctuation increasing characteristics are monitored, it indicates that there are soft and hard interlayers in the transition zone. Implement the "segmented control" strategy: divide the excavation process into multiple short cycles according to the characteristics of the formation, use an independent parameter combination for each cycle, and establish a smooth transition mechanism.

[0080] Specifically, the spatial distribution characteristics of the soft and hard interlayers are first identified through geological forecasts, drilling data, and the fluctuation patterns of tunneling parameters. When the torque and propulsion resistance show periodic fluctuations, the stratigraphic boundary position is determined according to the peak and valley distribution of the fluctuation curve, and the tunneling section is divided into several periodic units. The stratigraphic attributes of each periodic unit are analyzed to determine the distribution pattern and thickness ratio of the soft and hard layers.

[0081] After determining the cycle unit, an independent parameter control system is established for strata with different properties. In the soft layer section, a parameter combination based on soil pressure control is used to appropriately increase the cutter head speed and reduce the advancement speed; in the hard layer section, the cutting parameter optimization is mainly used. When entering the hard layer, the advancement speed is first reduced, and the cutter head speed is adjusted after the torque is stable.

[0082] In order to avoid system instability caused by sudden changes in parameters, a parameter transition mechanism is established between adjacent periodic units. By presetting the parameter change curve, the timing of parameter adjustment is ensured to match the law of formation changes, ensuring that it is always in a controllable state.

[0083] When the step-increasing feature is detected, it indicates that the rock mass strength increases in a step-like manner. Start the "temporary transition" strategy: when a torque mutation is detected, immediately reduce the advancement speed to avoid excessive impact on the cutter. At the same time, observe the trend of soil pressure changes. If the soil pressure fluctuates rapidly, appropriately increase the amount of replenishment to maintain the stability of the excavation surface.

[0084] The nature of the interlayer is determined based on the torque fluctuation characteristics: if the torque continues to rise, it indicates that the interlayer is strong, and the propulsion speed needs to be further reduced and the cutter head speed needs to be increased; if the torque fluctuates in a pulsed manner, it indicates that the interlayer is thin or broken, and a transition can be made by adjusting the propulsion speed.

[0085] When the torque begins to drop, first restore the propulsion speed to half of the normal level and observe the system response; if the torque remains stable, gradually increase the propulsion speed and adjust the cutter head speed accordingly until the normal parameter combination is restored.

[0086] During the entire transition process, pay close attention to changes in slag discharge characteristics. If large pieces of rock chips or abnormal particle size distribution appear in the slag discharge, the transition time needs to be extended to avoid increased tool wear.

[0087] After entering the weathered rock section, the control strategy turns to rock mass property control. By analyzing the integrity and weathering degree of the rock mass, a regional control strategy is established. Groundwater control is mainly based on fissure water, with a focus on preventing local water inrush risks. The cutterhead system optimizes parameter combinations based on rock mass characteristics and establishes a cutter protection mechanism. Earth pressure control is switched to support pressure mode, and the shield tail system selects the appropriate slurry ratio based on rock mass characteristics.

[0088] Furthermore, in the weathered rock-intact rock composite layer, the control of rock mass characteristics is the core, and the impact of groundwater is relatively small. The control of weathered rock sections is centered on rock support and fissure water control. The stress distribution of the excavation surface is tracked in real time through a multi-point pressure monitoring system, and fissure water pressure monitoring points are arranged to grasp the groundwater status. The cutterhead system sets benchmark parameters according to the characteristics of weathered rock and continuously monitors the stress state and wear of the cutter. When the formation begins to change, it is first predicted by the characteristics of rock mass integrity. When the excavation surface resistance changes from uneven to uniform, and the integrity of the rock block gradually increases, it indicates that it is entering the transition zone of intact rock. At the same time, the change in the distribution characteristics of fissure water pressure also provides an important basis for judging the formation conversion. At this time, the focus is on the torque change characteristics, including three typical change modes: uniform rise, pulse rise, or sudden rise.

[0089] When uniform rising characteristics appear, it indicates that the slightly weathered transition zone has been entered. Start the "uniform transition" strategy: keep the cutter head rotation speed stable and adjust the propulsion speed to adapt to the change in rock strength. The rock support pressure is gradually adjusted as the integrity increases, and the shield tail system optimizes the slurry ratio according to the degree of crack development. At the same time, pay close attention to the stress state of the rock mass to ensure the stability of the excavation surface.

[0090] Specifically, the change in rock mass strength at the excavation face is mainly monitored through three key indicators: cutter torque, thrust pressure, and excavation specific energy. When the torque shows a uniform upward trend, the torque increase rate is analyzed first. A slow and uniform increase indicates that the rock mass strength increases gradually, while a fast and uniform increase indicates a large increase in strength.

[0091] In the gradual increase stage, the propulsion speed is adjusted in "gradual mode": when the torque increase is within the reference value range, the propulsion speed is kept basically stable, and only fine-tuning is performed to eliminate fluctuations. As the torque continues to rise beyond the reference range, the propulsion speed begins to decrease. The speed reduction process adopts a continuous gradual change method to avoid sudden changes that cause stress concentration on the excavation surface. At the same time, the changes in excavation specific energy are observed. When the excavation specific energy is stable in a new reasonable range, it is confirmed that the propulsion speed matches the rock mass strength.

[0092] In the rapid increase stage, the propulsion speed is adjusted in a "step mode": first, the propulsion speed is quickly reduced to a safe level, and then a new propulsion speed is gradually established according to the torque response characteristics. After each adjustment step, the stress distribution of the excavation surface is observed, and the next adjustment is made after confirming that the stress level is within a reasonable range. The optimal propulsion speed is gradually achieved through multiple small adjustments to avoid system instability caused by large adjustments.

[0093] The adjustment of the advancement speed also needs to be combined with the change in rock mass integrity. When the rock mass integrity increases, its deformation resistance is enhanced, and the adjustment step of the advancement speed is appropriately increased. However, it is necessary to pay attention to the local stress concentration of the excavation face to prevent local damage to the rock mass due to improper adjustment of the advancement speed. By continuously analyzing the characteristics of the rock mass integrity of the excavation face, accurate guidance can be provided for the adjustment of the advancement speed.

[0094] At the same time, a linkage mechanism between advancement speed and soil pressure control is established. When the advancement speed is adjusted, the soil bin pressure is adjusted accordingly to maintain the pressure balance of the excavation surface. A lower advancement speed requires a relatively higher support pressure, and vice versa. Ensure the stability of the excavation surface and prevent collapse or water inrush due to pressure imbalance.

[0095] When pulse rising characteristics are detected, it indicates the existence of interlayered lithologies. Implement the "dynamic adaptation" strategy: establish the corresponding relationship between torque change and lithology conversion, and predict stratum changes based on torque characteristics. Cutting parameters are dynamically adjusted with lithology changes to ensure excavation efficiency. A rapid response mechanism needs to be established for rock support pressure, and corresponding support measures should be taken for different lithology characteristics. The shield tail system adjusts grouting parameters according to the characteristics of fracture development to ensure support effect.

[0096] Specifically, the analysis of the torque mutation rise characteristics focuses on three key indicators: mutation amplitude, duration and recovery characteristics. The mutation amplitude reflects the strength of the hard rock block, expressed as a multiple of the benchmark torque. The duration reflects the scale of the hard rock block. Short-term mutations indicate that local hard rock blocks are encountered, and continuous mutations indicate that hard rock layers have been entered. The recovery characteristics reflect the state of the surrounding rock mass. Rapid recovery indicates that the hard rock block is relatively isolated, and slow recovery indicates that the strength of the surrounding rock mass is also increasing.

[0097] The cutter head speed adjustment adopts a "three-stage control" strategy. The first stage is an emergency response. When the torque mutation amplitude exceeds 1.5 times the baseline value, the cutter head speed is immediately reduced by 20-30%, and the propulsion speed is reduced to 30-40% of the baseline value. Observe the torque response to ensure system stability. Observe the torque response characteristics after speed reduction. If the torque drops significantly but remains at a high level, it indicates that the initial speed reduction is basically reasonable and needs to be fine-tuned and optimized. If the torque drop is not obvious, the speed needs to be further reduced.

[0098] During the speed adjustment process, a torque-speed response curve is established, and the optimal working range is determined through multi-point testing. The speed adjustment adopts a small step increase and decrease method, and the adjustment range is controlled at 5-10% each time to observe the torque change trend. When the torque fluctuation tends to be stable and is within a reasonable range, it means that the temporary best matching state has been achieved. Find the optimal parameter combination under the current formation conditions.

[0099] After determining the optimal speed range, maintain the torque in the ideal range through fine adjustment. If the torque is continuously high but the fluctuation is small, appropriately reduce the speed to increase the single-tool cutting efficiency. If the torque fluctuates periodically, the speed needs to be adjusted to eliminate resonance. At the same time, closely monitor the tool stress state and immediately fine-tune the parameters if abnormalities are found.

[0100] When a sudden rise occurs, it indicates that a hard rock section has been entered. The "protection priority" strategy is adopted: the cutter head speed and propulsion speed are adjusted quickly to avoid excessive wear of the cutter. The rock support pressure is turned to the active support mode, focusing on preventing local spalling. At the same time, the monitoring and treatment of the fault fracture zone are strengthened to prevent the risk of water inrush or collapse. The shield tail system needs to strengthen the filling effect of the joints and fissures in a targeted manner.

[0101] Specifically, the core of the "protection priority" strategy is to minimize the risk of tool wear and damage while meeting the excavation efficiency. When the torque jumps by more than 50%, it indicates that the hard rock section has been entered, and the protection mode is immediately activated.

[0102] First, the speed is quickly reduced: the cutter head speed is reduced to about 65% of the current speed within 3-5 seconds. The initial response speed is crucial to protecting the cutter, and the initial impact often causes the most severe wear. At the same time, the propulsion speed is quickly reduced to 40-50% of the current speed. Although the reduction in propulsion speed will affect the excavation efficiency, it will significantly reduce the impact of the cutter. After completing the rapid response, further fine-tuning is performed.

[0103] The optimal parameter combination is determined by analyzing the force characteristics of the cutter: First, the corresponding relationship between the cutter head speed and the cutter wear rate is established. In the hard rock section, the cutter wear rate is proportional to the square of the speed. Through a large amount of historical data, the speed range with the minimum wear rate is found.

[0104] The fine adjustment of the propulsion speed is guided by the cutter torque, and the torque fluctuation is continuously monitored. When the torque fluctuation is controlled within 20%, it can be considered that the current propulsion speed is basically reasonable. If the torque fluctuation increases, the propulsion speed needs to be further reduced; if the torque fluctuation is small and stable, the propulsion speed should be appropriately increased to improve efficiency. Each adjustment range is controlled between 5-8% to ensure a smooth transition.

[0105] The implementation of the entire protection strategy requires the establishment of a rapid response mechanism. The entire process from discovering a torque mutation to completing parameter adjustment should be controlled within 1 minute. At the same time, during the parameter adjustment process, it is necessary to pay close attention to tool temperature changes and start the forced cooling system when necessary to prevent overheating damage.

[0106] After entering the complete rock section, the control strategy shifts to hard rock excavation mode. By analyzing the rock strength and joint development characteristics, a regional control strategy is established. Rock support is mainly preventive support, and the impact of excavation disturbance is closely monitored. The cutterhead system continuously optimizes the parameter combination to ensure the excavation efficiency while ensuring the service life of the cutter. The shield tail system selects the appropriate grouting scheme based on the joint and fissure characteristics.

[0107] Furthermore, in the soft soil-sand-pebble-weathered rock composite layer, a multiple conversion control system needs to be established. In the soft soil section, deformation control is the core, and the stability of the excavation surface is ensured through multi-point pressure monitoring and displacement monitoring. The earth pressure sensor array monitors the pressure distribution in real time, and pore water pressure monitoring points are arranged to grasp the groundwater status. The cutterhead system adopts a low torque configuration to ensure uniform soil crushing.

[0108] The first stratum conversion occurs when the soft soil transitions to sand and gravel. When the soil pressure distribution changes from uniform to local concentration and the permeability is significantly enhanced, it indicates that we are entering the sand and gravel transition zone. At this time, we should focus on the characteristics of soil pressure change, which are mainly manifested in the intensification of pressure fluctuations, increase in permeability pressure and unstable torque. Start the "smooth transition" strategy: maintain a high support pressure on the excavation surface, and adapt to the stratum changes by adjusting the cutterhead speed and propulsion speed. At the same time, strengthen the control of the permeability of the sand and gravel layer to prevent groundwater from getting out of control.

[0109] The second stratigraphic transition occurs when gravel transitions to weathered rock. When the pressure distribution changes from discrete to concentrated, and the local pressure peak begins to appear, it indicates that we are entering the weathered rock transition zone. At the same time, pay attention to the transition characteristics of groundwater conditions from pore water to fissure water. At this time, the torque change shows characteristics such as continuous rise, fluctuating rise or sudden rise.

[0110] The "comprehensive control" strategy is adopted for dual conversion control: first, a stratum identification system of soft soil-sand and gravel-weathered rock is established, and the stratum conversion node is determined through multi-parameter comprehensive analysis. The earth pressure control system needs to have three modes: deformation control mode, permeability control mode and support pressure mode, and can automatically switch according to the stratum characteristics.

[0111] Specifically, the formation identification system is constructed based on the following key parameters: The soil pressure distribution characteristics are the most direct basis for judgment. The soft soil section is evenly distributed, the gravel section is locally concentrated, and the weathered rock section has an obvious pressure peak. The soil permeability characteristics are also an important indicator. The changes in formation permeability are determined by pore water pressure monitoring. The torque characteristics reflect the changes in soil strength, which are manifested as stable torque in the soft soil section, increased fluctuations in the gravel section, and continuous rise in the weathered rock section.

[0112] During the transformation from soft soil to gravel, the following indicators are monitored: the rate of change of soil pressure from uniform to uneven, the increase of which indicates that the transition zone is being entered; the growth rate of seepage pressure, which will increase significantly when entering the gravel layer; the fluctuation frequency of the cutter head torque, which changes from low frequency to high frequency, indicating that the formation structure has changed. When these indicators show a trend of change at the same time, the conversion preparation state is entered.

[0113] In the process of converting gravel to weathered rock, we mainly focus on: the transformation characteristics of soil pressure distribution from discrete to concentrated; the transformation process of pore water pressure to fracture water pressure; the transformation of torque from fluctuating state to continuous rising state. By analyzing the changing trends of these parameters in real time, we can predict the conversion nodes in advance and reserve sufficient time for parameter adjustment.

[0114] The three modes of the earth pressure control system have different control focuses: the deformation control mode is mainly used in soft soil sections, ensuring the stability of the excavation surface through multi-point displacement monitoring, and establishing a correlation between the deformation rate and the support pressure; the seepage control mode is aimed at sand and gravel sections, focusing on controlling the seepage pressure to prevent groundwater from getting out of control; the support pressure mode works in weathered rock sections, determining the optimal support pressure based on the integrity characteristics of the rock mass.

[0115] Mode switching adopts a gradual transition method: when the formation characteristics are monitored to begin to change, the mixed control state is entered. For example, when switching from soft soil to sand and gravel, deformation control and permeability control are enabled at the same time, and the weights of the two modes are gradually adjusted according to parameter changes until the complete transition to the permeability control mode is achieved. This avoids system instability caused by sudden changes in the control mode.

[0116] The groundwater control strategy requires the establishment of a dual control system of pore water and fissure water. In the soft soil section, the focus is on preventing the pore water pressure from being too high, and in the gravel section, the focus is on controlling the seepage pressure. After entering the weathered rock, the control mode is switched to the fissure water control mode. At the same time, a water pressure rapid response mechanism is established to prevent groundwater from getting out of control.

[0117] The support system adopts the "layered design" strategy: synchronous grouting is mainly used for soft soil sections to ensure the stability of the formation; advanced support is strengthened in the gravel section to prevent the collapse of loose formations; and appropriate support parameters are selected for the weathered rock section according to the characteristics of the rock mass. A smooth transition mechanism for support parameters is established between each layer to avoid sudden changes in the support effect. The slurry ratio is adjusted synchronously, and high-permeability slurry is used in the soft soil section for reinforcement; fast-setting slurry is used in the gravel section to prevent slurry loss; and the weathered rock section selects the appropriate slurry strength according to the degree of crack development.

[0118] During the entire composite transition process, the following situations are monitored: when the torque fluctuates abnormally, the formation state is analyzed immediately and the cutting parameters are adjusted; when the pressure distribution is unbalanced, the replenishment strategy is quickly adjusted to restore the balance; when the local water pressure is abnormal, the support and drainage measures in the area are strengthened in time; when the grouting effect is not ideal, the grouting plan is adjusted; at the same time, the deformation trend of the excavation surface is closely monitored and preventive measures are taken in time. If special circumstances occur, such as encountering a fault fracture zone, the enhanced support mode is automatically entered: increase the grouting pressure, increase the number of grouting times, and perform secondary reinforcement when necessary.

[0119] S3: Establish an optimization model for tunneling speed based on the formation discriminant function, realize intelligent control of tunneling parameters through the combined effect of differentiated monitoring parameters under different geological conditions; calculate the optimal tunneling speed according to the dynamic changes of formation characteristics.

[0120] An adaptive control system is established according to different geological conditions, and the optimal excavation mode and parameter combination are determined through real-time monitoring and analysis of stratum characteristics. For each geological condition, three basic excavation modes are set: the high-efficiency mode pursues maximum excavation efficiency and is suitable for sections with stable geological conditions and good self-stability of surrounding rocks. At this time, the cutterhead speed and propulsion speed are maintained at a high level, and the soil bin pressure is controlled at a low range to reduce resistance; the balanced mode focuses on the comprehensive balance of efficiency and safety, and is suitable for sections with general geological conditions. All parameters are at a medium level to ensure a smooth and controllable construction process; the low-consumption mode emphasizes construction safety and is suitable for sections with complex or poor geological conditions. The stability of the excavation surface is ensured by reducing the cutterhead speed and propulsion speed and increasing the soil bin pressure.

[0121] According to the real-time monitoring of the formation characteristics data, including formation strength, integrity, permeability and other indicators, the most suitable excavation mode is automatically selected. In the soft soil section, the focus is on the deformation characteristics of the soil and the changes in pore water pressure. When the soil stability is good, the high-efficiency mode is preferred to improve the efficiency by increasing the cutter head speed and the propulsion speed, while ensuring that the soil pressure is slightly higher than the soil pressure to maintain the stability of the excavation surface; in the gravel section, pay attention to the permeability changes and soil pressure distribution characteristics, and give priority to the balance mode. By reasonably controlling the cutter head speed and propulsion speed, and appropriately increasing the soil bin pressure and grouting pressure to prevent water gushing and collapse; in the weathered rock section, focus on monitoring the integrity of the rock mass and the degree of joint development, select the appropriate excavation mode according to the rock mass conditions, and enable the low-consumption mode when necessary, and reduce the excavation parameters to ensure safety.

[0122] When a change in geological conditions is detected, the transition section excavation mode is automatically entered. This mode is characterized by the use of a progressive adjustment strategy to avoid instability caused by sudden changes in parameters. Specifically, the type of stratum to be entered is first identified, and then the target parameter combination is calculated, and then the various parameters are gradually adjusted according to the preset adjustment curve. For example, when transitioning from a soft soil layer to a sand and gravel layer, the cutter head speed will be gradually reduced, while the soil bin pressure will be slowly increased, and the grouting parameters will also be adjusted accordingly. The slurry ratio will gradually change from high permeability to fast setting type, and the grouting pressure will be dynamically adjusted according to the characteristics of the stratum. During the entire transition process, the system continuously monitors the changing trends of various parameters to ensure that the adjustment process is smooth and controllable.

[0123] Based on the above description, a stratum classification discriminant function is established, including: collecting stratum characteristic data under different geological conditions, including stratum strength test results, field permeability test data, rock and soil integrity evaluation index and other original data. These data sources include drilling sampling analysis, geological radar detection, advanced geological forecast and real-time monitoring data during shield tunneling.

[0124] The principal component analysis method is used to identify key characteristic parameters and determine the contribution of different characteristic parameters to the identification of stratum types. Through statistical analysis of a large number of engineering cases, the corresponding relationship between characteristic parameters and stratum types is established, and then the weight coefficients of various characteristics are determined. These weight coefficients reflect the importance of different characteristic parameters in stratum identification. For example, in the identification of soft soil layers, the weights of soil strength and compressibility indicators are relatively large, while in the identification of rock layers, the weights of rock integrity and joint development are more prominent.

[0125] At the same time, in order to deal with the gradual characteristics of the stratum transition zone, the distance function is introduced to describe the gradual characteristics of the parameters in the transition zone. Then the stratum classification discriminant function G(x) is established, which is expressed as: ; in, It is the stratum classification discriminant function, which characterizes the stratum type and characteristics of the current excavation face; For the The weight coefficient of each formation characteristic parameter reflects the importance of the characteristic parameter in formation identification; For the Standardized values ​​of formation characteristics, including measurable physical and mechanical parameters such as formation strength, permeability, and integrity index; is the sensitivity coefficient, which controls the rate of change of the function in the transition zone, and its value is determined by analyzing historical engineering data; The distance between the current excavation position and the starting point of the stratum transition zone, which is obtained in real time through the shield machine position monitoring system; is the total number of stratigraphic characteristic parameters involved in the identification.

[0126] It contains multiple standardized parameters that reflect the characteristics of the formation: for strength characteristics, it includes mechanical indicators such as formation compressive strength, shear strength, and deformation modulus; for physical characteristics, it includes basic physical quantities such as water content, porosity, density, and permeability; for structural characteristics, it includes geological structural parameters such as integrity index, degree of fracture development, and rock and soil classification index. These original parameters are converted into dimensionless values ​​after standardization, so that parameters of different dimensions can be calculated comprehensively. The standardization process uses the Z-score standardization method to map all eigenvalues ​​to a unified interval. A correspondence between eigenvalues ​​and formation types is established to achieve accurate description and discrimination of the formation status. It can not only identify a single formation type, but also reflect the location and range of the transition zone through numerical changes. By setting different threshold intervals, The calculation results are mapped to specific stratum types to achieve automatic stratum identification and classification.

[0127] Based on the discriminant function of stratigraphic classification Output value , determine the current geological conditions, and based on different geological conditions, further determine the factors affecting the excavation speed, including: stratum type, stratum strength, soil bin pressure, and cutter head torque. Then multiply the benchmark speed with these four influencing factors to obtain the optimal excavation speed under different geological conditions.

[0128] Specifically, the strata were classified through geological survey reports, and differentiated monitoring parameter combinations were set for different geological conditions, while taking into account the special monitoring needs of the geological transition zone. Based on the idea of ​​hierarchical control, the precise regulation of tunneling parameters can be better achieved. Then, the optimal tunneling speed is further calculated, and the formula is expressed as: ; in, For the optimal excavation speed, is the benchmark excavation speed, which is determined by the shield machine equipment parameters. To measure the formation strength, is the standard formation strength, is the soil bin pressure, To measure the cutter head torque, is the rated cutter head torque. is the formation adaptability coefficient, A continuous function of change, is the strength correction index, which reflects the sensitivity of different formations to strength. is the pressure sensitivity coefficient, which controls the influence of soil bin pressure on excavation speed. It is the torque correction coefficient, which adjusts the limiting effect of torque on the excavation speed.

[0129] Furthermore, is the stratum adaptability coefficient. In the soft soil layer, the function value is close to the minimum value, indicating that the stratum conditions have a greater restriction on the excavation speed. When it transitions to the sand and gravel layer, the function value begins to increase significantly. After entering the weathered rock layer, the function value continues to rise but the increase rate slows down. When it reaches the intact rock layer, the function value is close to the maximum value. For composite strata, the corresponding function value range is determined according to its main components, and the influence of the mixing effect is considered.

[0130] Strength Modification Index In soft soil strata, since the influence of stratum strength on excavation speed is relatively small, the correction index takes the minimum value. As the geological strength increases, the correction index gradually increases until it reaches the maximum value. The calculation process is to first divide the stratum discrimination value by its maximum possible value for normalization, and then perform linear interpolation with the maximum and minimum correction indices to obtain the strength correction index under different stratum conditions.

[0131] Pressure sensitivity coefficient Use an inverse relationship to describe. Soil pressure control in soft soil is more important and requires a larger sensitivity coefficient. As the geological strength increases, the sensitivity coefficient gradually decreases. When calculating, subtract the current discrimination value from the maximum possible value of the formation discrimination and then normalize it to establish the relationship between the pressure sensitivity coefficient and the formation conditions. When the formation discrimination value is close to the minimum, the pressure sensitivity coefficient reaches the maximum value; as the discrimination value increases, the sensitivity coefficient gradually decreases.

[0132] Torque correction factor Using a proportional relationship to express, in soft soil, the cutter head torque will not reach the limit value, and the correction coefficient should be small. When calculating, the formation discrimination value is divided by its maximum possible value for normalization, and then multiplied by the set maximum correction coefficient to obtain the relationship between the torque correction coefficient and the formation conditions.

[0133] Based on the optimal excavation speed, the shield tunneling construction can be precisely controlled and the efficiency can be improved. Under the premise of ensuring construction safety, the excavation parameters can be automatically adjusted according to the real-time changes in the formation conditions, effectively reducing the construction risks caused by human experience and judgment. When the shield machine is excavating in a homogeneous stratum, it can be based on the formation discrimination value. Maintain a stable excavation speed to keep the cutter head torque and soil bin pressure in the optimal working range; in complex transitional strata, the stratum adaptability coefficient , Strength Correction Index , Pressure sensitivity coefficient and torque correction factor The synergistic effect of the tunneling speed can achieve a smooth transition, avoiding various construction problems caused by sudden adjustments in traditional construction. At the same time, since the comprehensive impact of stratum characteristics on tunneling parameters is taken into account, surface settlement can be effectively controlled and construction quality can be improved. Especially under complex stratum conditions, it can help construction personnel better cope with changes in geological conditions and ensure the continuity and reliability of shield construction.

[0134] In summary, the shield machine real-time data monitoring and operation efficiency improvement method based on the embodiment of the present invention is explained, which determines whether there are signs of infection at the patient's puncture site by performing time series analysis on high-definition images of the patient's puncture site at different time points within the target monitoring time period. In this way, the accuracy and timeliness of infection monitoring can be improved, which helps to detect signs of infection at an early stage, so as to take timely measures to reduce the incidence and severity of infection.

Claims

1. A method for real-time data monitoring and operation efficiency improvement of a shield machine, characterized in that: include: Multifunctional sensor modules are arranged in the cutterhead system, propulsion system, soil bin system and shield tail system of the shield machine to collect operating parameters; Process data through local data processing unit to generate geological survey reports; Based on the geological survey report, the geological conditions are divided and differentiated monitoring parameter combinations are set for different geological conditions; when in the geological transition zone, the monitoring schemes of adjacent geological types are activated at the same time; Based on different geological conditions, a tunneling speed optimization model based on the stratum discriminant function is established. Through the combined effect of differentiated monitoring parameters under different geological conditions, intelligent regulation of tunneling parameters is realized; the optimal tunneling speed is calculated according to the dynamic changes of stratum characteristics.

2. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 1, characterized in that: Based on the geological survey report, the geological conditions are divided into soft soil layer, sand and gravel layer, weathered rock layer, intact rock layer and composite layer; The composite strata include: a soft soil-sand and gravel composite layer, a sand and gravel-weathered rock composite layer, a soft soil-weathered rock composite layer, a weathered rock-intact rock composite layer and a soft soil-sand and gravel-weathered rock composite layer.

3. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 2, characterized in that: In the soft soil-sand-pebble composite layer, when entering the transition zone, the formation conversion is judged by the pressure distribution and groundwater changes, and corresponding adjustment strategies are adopted according to the torque change mode, including: When the torque changes in a step-by-step manner, the cutter head speed is gradually increased, the propulsion speed is reduced, and the soil pressure and filling amount are dynamically adjusted; When the torque changes in a fluctuating manner, optimize the cutting parameters and adjust the soil pressure and grouting parameters in advance; As torque changes gradually increase, smoothly adjust propel speed and earth pressure control.

4. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 3 is characterized in that: In the sand-pebble-weathered rock composite layer, when the layer enters the weathered rock transition, different strategies are adopted according to the torque change mode, including: When the torque changes continuously increase, it indicates that the weak weathering zone has been entered. The advancement speed is reduced, the soil pressure is gradually adjusted to the support mode, and the shield tail system increases the slurry strength; When the torque changes in a fluctuating upward manner, it indicates that the broken weathering zone has been entered. Real-time collection of parameters is used to establish the corresponding relationship between geological conditions and construction parameters, and to optimize the ratio of cutter head speed and propulsion speed. When the torque changes suddenly and rises, it indicates that hard rock or strongly weathered rock is encountered. Reduce the propulsion speed, adjust the cutter head speed, and temporarily increase the slurry strength.

5. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 4, characterized in that: In the soft soil-weathered rock composite layer, when entering the transition zone, the construction parameters are adjusted according to the torque change and dynamically controlled in combination with the groundwater conditions, including: When the torque changes continuously and gradually, it indicates that the transition zone between soft soil and rock mass has been entered. The soil bin pressure is adjusted to form a pressure gradient, and the propulsion speed is gradually reduced while observing the torque changes. When the torque changes in a fluctuating and increasing manner, it indicates that there are soft and hard interlayers in the transition zone. In the soft layer section, soil pressure is mainly controlled, the cutter head speed is increased and the advancement speed is reduced; in the hard layer section, the cutting parameters are optimized, the advancement speed is reduced first and then the speed is adjusted; When the torque changes in a step-by-step manner, it indicates that the rock strength increases in a step-by-step manner. Immediately reduce the advancement speed, maintain the stability of the excavation face, and adjust the advancement speed and cutter head speed according to the properties of the interlayer.

6. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 5, characterized in that: In the weathered rock-intact rock composite layer, when the layer transitions to intact rock, different strategies are adopted according to the torque change mode, including: When the torque changes evenly, it indicates that it has entered the slightly weathered transition zone. Keep the cutter head speed stable, adjust the propulsion speed to adapt to the change in rock strength, and optimize the slurry ratio of the shield tail system. When the torque changes in a pulsed manner, it indicates the existence of interlayered lithologies. The corresponding relationship between torque changes and lithology conversion is established, and the cutting parameters are adjusted dynamically to quickly respond to different lithology characteristics. When the torque changes suddenly, it indicates entering a hard rock section. The cutter head rotation speed and propulsion speed should be adjusted quickly to strengthen rock support.

7. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 6, characterized in that: Based on the different geological conditions, the stratigraphic characteristic parameters are extracted through principal component analysis, which are multiplied by the corresponding weight coefficients. The sensitivity coefficients are introduced to control the change rate of the stratigraphic transition zone. The distance between the excavation position and the starting point of the transition zone is dynamically adjusted to establish a stratigraphic classification discriminant function.

8. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 7, characterized in that: Based on the stratum classification discriminant function, the current geological conditions are determined, and based on different geological conditions, the influencing factors of the excavation speed are further determined. The reference speed is combined with the influencing factors to obtain the optimal excavation speed under different geological conditions.

9. The method for real-time data monitoring and operation efficiency improvement of a shield machine according to claim 8, characterized in that: The calculation of the optimal excavation speed also includes formation adaptability coefficient, strength correction index, pressure sensitivity coefficient and torque correction coefficient; The formation adaptability coefficient increases gradually from soft soil to intact rock according to the formation type; The strength correction index reflects the influence of formation strength through normalization and linear interpolation; The pressure sensitivity coefficient adopts an inverse relationship to describe the importance of soil layer pressure and decreases as the strength of the formation increases; The torque correction coefficient adopts a proportional relationship and reflects the limiting effect of the cutter head torque on the excavation speed through normalized calculation.

10. A shield machine real-time data monitoring and operation efficiency improvement system, characterized in that: include: The data processing module is used to collect the operating parameters of each system of the shield machine in real time; the data is processed through the local data processing unit to generate a geological survey report; The differentiated monitoring module is used to divide geological conditions according to geological survey reports and set differentiated monitoring parameter combinations for different geological conditions; The optimization module is used to establish an optimization model for tunneling speed based on the formation discriminant function, realize intelligent regulation of tunneling parameters through the combined effect of differentiated monitoring parameters under different geological conditions, and calculate the optimal tunneling speed according to the dynamic changes of formation characteristics.

Images