A double-liquid grouting pressure stabilizing compensation method and system based on multi-parameter regulation

Abstract

The application discloses a kind of based on the double-liquid grouting pressure stabilizing compensation method and system of multi-parameter regulation, belong to civil engineering intelligent control technical field. Including: obtaining real-time grouting pressure, construct the double-channel architecture of feedback and feedforward cooperation;Feedback channel is based on PID algorithm to calculate the feedback correction of pressure deviation;Feedforward channel is based on the stratum characteristic correlation model of recursive least squares method, according to stratum permeability coefficient and fracture development degree bias to predict pressure fluctuation trend, generate the feedforward compensation of flow and ratio compensation component;Through dynamic weight fusion algorithm, the weight proportion of feedback and feedforward is adaptively adjusted, and the integrated control instruction is synthesized;Drive double liquid pump group to execute, and according to pressure deviation level switching control mode, realize closed-loop pressure stabilizing control.The application realizes the accurate compensation of double-liquid grouting pressure, has strong geological adaptability, and gives consideration to the dual needs of consolidation strength and gel time.

Description

Technical Field

[0001] This invention belongs to the technical field of intelligent control in civil engineering, specifically relating to a dual-liquid grouting pressure stabilization compensation method and system based on multi-parameter regulation. Background Technology

[0002] Grouting technology is an important method for soil reinforcement and waterproofing in geotechnical engineering. The two-component grouting method uses cement grout and water glass in combination, which can flexibly control the gelation time of the grout and quickly form a high-strength solidified body in complex strata. Therefore, it is widely used in key projects such as tunnels crossing water-rich fractured zones and pre-reinforcement.

[0003] Existing grouting pressure control methods are mostly designed for single pumping systems or single grout systems, achieving pressure feedback regulation by real-time monitoring of pressure deviations and adjusting pump flow rates. However, these methods have significant shortcomings. First, their control architecture only covers a single pumping loop, failing to meet the needs of coordinated control of cement grout and water glass dual-liquid systems, and making it difficult to dynamically optimize the flow ratio of the two liquids. Second, existing technologies lack the ability to perform feedforward prediction based on geological parameters such as formation permeability coefficients and fracture development levels. Relying solely on deviation feedback regulation is insufficient to effectively cope with pressure fluctuations under complex geological conditions, resulting in poor pressure stability. These problems are particularly prominent when tunnels traverse high-risk strata such as fault fracture zones and karst cave development areas, easily leading to poor grouting reinforcement effects or even engineering accidents.

[0004] Therefore, how to achieve precise pressure stabilization and compensation during the dual-liquid grouting process and improve the adaptability to complex geological conditions is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-liquid grouting pressure stabilization and compensation method and system based on multi-parameter control, which can effectively solve the problems in the background art mentioned above.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control includes the following specific steps: Real-time grouting pressure values ​​are obtained, and a dual-channel control architecture is constructed that coordinates the feedback channel and the feedforward channel. The feedback channel calculates the deviation between the real-time grouting pressure value and the target pressure based on the proportional-integral-derivative control algorithm, and generates a feedback correction amount. The feedforward channel is based on the formation characteristic correlation model of recursive least squares method. It predicts the pressure fluctuation trend according to the formation permeability coefficient deviation and fracture development degree index deviation, and generates a feedforward compensation quantity that includes flow compensation component and ratio compensation component. The dynamic weight fusion algorithm adaptively adjusts the weight ratio of the feedback correction and the feedforward compensation based on the current absolute value of the pressure deviation and the formation complexity, and synthesizes them into a comprehensive control command. The comprehensive control command includes flow regulation information and ratio adjustment information. The dual-liquid pump group execution subsystem is driven by the comprehensive control command, and the control mode is switched according to the pressure deviation between the real-time grouting pressure value and the target pressure to complete the closed-loop stable control of the dual-liquid grouting pressure.

[0007] Furthermore, the step of obtaining the real-time grouting pressure value specifically includes: High-frequency response pressure sensors are installed at the outlet of the grouting pump, the middle section of the grouting pipeline, and the grouting hole to form a three-point pressure monitoring network and collect raw pressure signals. The original pressure signal is sequentially passed through a hardware low-pass filter, a finite impulse response filter for band-limited filtering, and an adaptive filtering unit based on the minimum mean square error criterion to suppress power frequency interference, and then the pressure signal processed by the adaptive filtering unit is output. The pressure signal processed by the adaptive filtering unit is subjected to time-domain difference operation with the pressure signal at the previous moment to calculate the pressure change rate, and the pressure value at the current moment and the pressure change rate are combined together to form a two-dimensional pressure state vector. The two-dimensional pressure state vector is input into a Kalman filter, and the optimal state is estimated based on the state-space model to output the real-time grouting pressure value.

[0008] Furthermore, in the step of generating the feedback correction amount by calculating the deviation between the real-time grouting pressure value and the target pressure based on the proportional-integral-derivative control algorithm, the feedback channel includes: The control law expression for the proportional-integral-derivative (PID) control algorithm is: ,in The feedback correction amount, The pressure deviation is mentioned above. The integral coefficient is... These are the differential coefficients; proportionality coefficient An adaptive tuning strategy is adopted: when the absolute value of the pressure deviation is greater than 0.5 MPa, the proportional coefficient... Set to a larger value; when the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa, the proportional coefficient... Set to a medium value; when the absolute value of the pressure deviation is less than 0.1 MPa, the proportionality coefficient... Set to a smaller value.

[0009] Furthermore, in the step of generating a feedforward compensation quantity containing flow compensation and proportion compensation components, the feedforward channel is based on a formation characteristic correlation model using recursive least squares. This model predicts pressure fluctuation trends based on formation permeability coefficient deviation and fracture development degree index deviation. The stratigraphic characteristic correlation model is a multi-input single-output linear regression model with time delay. The mathematical expression of the multi-input single-output linear regression model with time delay is: ,in For the predicted pressure fluctuation amount, This refers to the deviation in the permeability coefficient of the formation. This refers to the deviation of the fracture development degree index. This represents the pressure change at the previous moment. , , This is the model parameter vector; The parameter update formula for the recursive least squares method includes a forgetting factor. and update the gain matrix The forgetting factor The value range is between 0.95 and 0.99; The flow compensation component in the feedforward compensation is calculated based on the magnitude of the deviation of the permeability coefficient from the design value. The calculation formula for the flow compensation component is as follows: ,in This is the flow compensation coefficient; The proportionate compensation component in the feedforward compensation is calculated based on the degree of formation fracture development, and the calculation formula for the proportionate compensation component is as follows: ,in This is the matching compensation coefficient.

[0010] Furthermore, in the step of adaptively adjusting the weight ratio of the feedback correction and the feedforward compensation based on the current absolute value of the pressure deviation and the formation complexity using a dynamic weight fusion algorithm to synthesize a comprehensive control command: The calculation expression for the dynamic weight fusion algorithm is as follows: ,in The comprehensive control command, The dynamic weighting coefficients for the feedback channel. The feedback correction amount, These are the dynamic weighting coefficients for the feedforward channel. The feedforward compensation amount is given, and satisfies the following conditions: ; When the absolute value of the pressure deviation is in the range of 0 to 0.1 MPa and the fracture development index When the value is less than 0.3, set the dynamic weighting coefficient of the feedback channel. The dynamic weighting coefficient of the feedforward channel ; When the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa and the fracture development index When the value is between 0.3 and 0.7, the dynamic weighting coefficient of the feedback channel is set. The dynamic weighting coefficient of the feedforward channel ; When the absolute value of the pressure deviation is greater than 0.5 MPa and the fracture development degree index When the value is greater than 0.7, the dynamic weighting coefficient of the feedback channel is set. The dynamic weighting coefficient of the feedforward channel ; Furthermore, when a rapid increase in the pressure deviation is detected, the dynamic weighting coefficient of the feedforward channel is adjusted based on the above configuration. Temporarily increase by 10% to 20%, while correspondingly reducing the dynamic weighting coefficient of the feedback channel. .

[0011] Furthermore, the integrated control command includes flow regulation information and ratio adjustment information: The flow rate adjustment information is expressed as a percentage change in flow rate. When the percentage change in flow rate is positive, it indicates that the total output flow rate of the two liquids needs to be increased. When the percentage change in flow rate is negative, it indicates that the total output flow rate of the two liquids needs to be decreased. The ratio adjustment information is expressed in the form of a ratio adjustment coefficient of volume flow rate of liquid A and liquid B. The base value of the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is 1. When the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is greater than 1, it means that the proportion of liquid B needs to be increased. When the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is less than 1, it means that the proportion of liquid B needs to be decreased.

[0012] Furthermore, in the step of driving the dual-liquid pump group execution subsystem using the comprehensive control command, the comprehensive control command is received through the dual-liquid ratio dynamic adjustment module, which integrates a ratio calculation unit and a flow distribution unit. The proportioning calculation unit calculates the target proportion value at the current moment based on the proportioning adjustment information in the comprehensive control command. The calculation logic of the proportioning calculation unit is as follows: when the comprehensive control command includes a positive flow rate adjustment and the increase of the positive flow rate adjustment exceeds 5%, the proportion of liquid B is increased by 2% to 5% based on the current proportion; when the comprehensive control command includes a negative flow rate adjustment and the decrease of the negative flow rate adjustment exceeds 5%, the proportion of liquid B is decreased by 2% to 5% based on the current proportion. The flow distribution unit calculates the target flow rate of the liquid A pump based on the target ratio value at the current moment and the flow adjustment information in the comprehensive control command, using the following formula. And the target flow rate of the ethyl alcohol pump : , ,in This represents the total output flow rate of the two liquids. The target allocation value at the current time. This represents the ratio of the volumetric flow rates of liquid B to that of liquid A.

[0013] Furthermore, in the step of switching the control mode based on the magnitude of the pressure deviation between the real-time grouting pressure value and the target pressure: When the pressure deviation When the pressure exceeds 0.5 MPa, a fast adjustment mode is entered. In this fast adjustment mode, the dynamic weighting coefficient of the feedforward channel is adjusted. Temporarily increase to above 0.8, temporarily suppress integral action to avoid integral saturation, and set the adjustment range of pump flow rate to 1.5 times that of normal mode; When the pressure deviation When the pressure is between 0.1MPa and 0.5MPa, it enters the fine adjustment mode. In the fine adjustment mode, the integral action is used to eliminate steady-state error, and the adjustment range of the pumping flow rate adopts a gradual strategy to avoid overshoot. When the pressure deviation When the pressure is less than 0.1 MPa, the system enters a steady-state maintenance mode. In this mode, the pressure is maintained by a small flow rate adjustment, the ratio is kept constant, and the pressure fluctuation is controlled within ±0.05 MPa of the target pressure.

[0014] Furthermore, it also includes a dynamic allocation control strategy for different zones: The formation characteristic sensing unit includes multiple distributed permeability coefficient sensors and multiple distributed fracture development degree assessment modules. The multiple distributed permeability coefficient sensors and multiple distributed fracture development degree assessment modules are respectively set on different section nodes of the grouting pipeline. The permeability coefficient data and fracture development degree index data of each section are summarized by the data acquisition unit and interpolated according to spatial location to generate formation parameter distribution curves along the grouting path. The dual-liquid ratio dynamic adjustment module adopts a multi-level control architecture: the first level is the overall grouting path ratio layer, which determines the overall ratio base value based on the average formation parameters of the formation parameter distribution curve along the grouting path; the second level is the section ratio adjustment layer, which calculates the section ratio adjustment amount based on the deviation of the formation parameters of each section from the average formation parameters; the third level is the real-time ratio fine-tuning layer, which performs fine-tuning of the ratio based on pressure feedback information. The proportioning adjustment commands of the overall grouting path proportioning layer, the section proportioning adjustment layer, and the real-time proportioning fine-tuning layer are weighted and fused before being output to the dual-liquid pump group execution subsystem. The weight of the overall grouting path proportioning layer is preset to 0.5, the weight of the section proportioning adjustment layer is preset to 0.3, and the weight of the real-time proportioning fine-tuning layer is preset to 0.2.

[0015] A dual-liquid grouting pressure stabilization and compensation system based on multi-parameter control includes: The dual-liquid pump set execution subsystem includes a liquid A pump for conveying cement slurry and a liquid B pump for conveying water glass solution. The speed of liquid A pump and liquid B pump is adjusted by independent variable frequency drive controllers. The formation characteristic sensing unit includes a permeability sensor for real-time measurement of formation permeability coefficient, and a fracture development degree assessment module for quantitatively evaluating the fracture development degree index based on the pressure response curve characteristics during grouting. The real-time pressure data acquisition subsystem includes high-frequency response pressure sensors installed at the outlet end of the grouting pump, the middle section of the grouting pipeline, and the grouting orifice. The high-frequency response pressure sensors are used to acquire raw pressure signals and perform analog-to-digital conversion. The feedback channel control subsystem is equipped with a proportional-integral-derivative control algorithm, which is used to calculate the feedback correction amount based on the deviation between the real-time grouting pressure value and the target pressure. The feedforward channel control subsystem embeds a formation characteristic correlation model based on the recursive least squares method, which is used to calculate the feedforward compensation amount including flow compensation component and ratio compensation component based on the formation permeability coefficient deviation and fracture development degree index deviation. The dynamic weighted fusion calculation subsystem is used to dynamically adjust the weight ratio of the feedback correction amount and the feedforward compensation amount according to the current absolute value of the pressure deviation and the formation complexity, and fuse them to generate a comprehensive control command that includes flow regulation information and ratio adjustment information. The dual-liquid ratio dynamic adjustment module is connected to the dynamic weight fusion calculation subsystem and the dual-liquid pump group execution subsystem, respectively. The dual-liquid ratio dynamic adjustment module integrates a ratio calculation unit for calculating the target ratio value and a flow distribution unit for calculating the target flow rate of pump A and pump B.

[0016] In summary, this application includes at least one of the following beneficial technical effects: 1. This invention establishes a coupled control mechanism between the flow rate ratio of the two liquids and the grouting pressure. By using dynamic weight fusion logic, the feedforward compensation command and the feedback correction command are fused together, so that the comprehensive control command simultaneously includes flow rate adjustment information and ratio adjustment information, thereby achieving precise pressure control of the two liquids in synergy. 2. This invention adds a formation characteristic sensing unit to collect parameters such as formation permeability coefficient and fracture development degree in real time, providing geological basis for the feedforward channel and solving the technical problem that the existing technology lacks geological adaptability control capability; 3. This invention establishes a feedback-feedforward dual-channel collaborative control architecture. The feedforward channel performs feedforward compensation based on the pressure fluctuation trend predicted by geological parameters, while the feedback channel performs feedback correction based on the real-time pressure deviation. The synergistic effect of the two channels significantly improves the ability to cope with pressure fluctuations in complex formations. 4. The present invention adopts a dual-liquid ratio dynamic adjustment module, which synchronously adjusts the output flow rate of the A liquid pump and the B liquid pump according to the comprehensive control command and dynamically adjusts the ratio, so that the gel time of the slurry is flexibly controllable within the preset time range, taking into account both the requirements of consolidation strength and gel time. Attached Figure Description

[0017] Figure 1 A schematic diagram of the overall scheme of the dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control; Figure 2 A schematic diagram illustrating the principle of a dual-channel control architecture that coordinates the feedback channel and the feedforward channel; Figure 3 This is a flowchart of the dynamic weight fusion algorithm. Figure 4 A schematic diagram illustrating the interaction and data flow between the dual-liquid pump unit and the pressure control linkage; Figure 5 This diagram illustrates the comparison of pressure control effects between a dual-channel collaborative control architecture and a single feedback control architecture. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the following description is provided in conjunction with the appendix. Figure 1 To be continued Figure 5 The present invention will be further described in detail below with reference to specific embodiments.

[0019] Firstly, the present invention provides a dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control. Its technical architecture includes the following core subsystems: a real-time pressure data acquisition subsystem, a formation characteristic sensing subsystem, a feedback channel control subsystem, a feedforward channel control subsystem, a dynamic weight fusion calculation subsystem, a dual-liquid ratio dynamic adjustment subsystem, and a dual-liquid pump group execution subsystem. These subsystems interact with each other through preset data interfaces and communication protocols, forming a complete closed-loop grouting pressure control system.

[0020] The real-time pressure data acquisition subsystem uses pressure sensors installed at key nodes in the grouting pipeline as its core acquisition unit. The pressure sensors are high-frequency response models, with technical specifications meeting the following requirements: sampling frequency not less than 500Hz, resolution not less than 0.01MPa, and signal transmission delay not exceeding 1ms. In actual deployment, pressure sensors are installed at the grouting pump outlet, the middle section of the grouting pipeline, and the grouting orifice, forming a three-point pressure monitoring network to achieve full-path sensing of grouting pressure changes. The raw pressure signal output by the sensor first undergoes preliminary filtering at the hardware level using a low-pass filter, with the cutoff frequency set to half the sampling frequency to eliminate noise components above the Nyquist frequency. Subsequently, the filtered digital signal enters the software level Kalman filter algorithm processing unit. This algorithm performs optimal estimation based on the system state-space model, effectively eliminating random noise and sensor measurement errors to obtain accurate real-time grouting pressure values.

[0021] The formation characteristic sensing unit constitutes the core information source of the feedforward channel, and its function is to collect and evaluate formation parameters in the grouting operation area in real time. This sensing unit consists of two components: a permeability sensor and a fracture development assessment module. The permeability sensor uses the transient pressure pulse method or the constant head permeability test method to measure the formation permeability in situ, covering a range from 10⁻⁶ to 10⁻² centimeters per second, with a measurement accuracy on the order of 10⁻⁷ centimeters per second. During the grouting operation, the permeability sensor continuously measures at preset time intervals, and the measurement data is transmitted in real time to the fracture development assessment module for comprehensive processing. The fracture development assessment module performs quantitative evaluation based on the pressure response curve characteristics during the grouting process, and the evaluation indicators include parameters such as pressure rise rate, pressure decay rate, pressure fluctuation frequency, and pressure peak characteristics. The specific assessment logic is as follows: The fracture development degree index is calculated based on the slope variation characteristics of the pressure response curve. When the pressure rise rate exceeds a preset threshold and the decay rate is lower than a set lower limit, it indicates a high degree of fracture development in the formation; when the pressure response curve exhibits stable characteristics and small fluctuations, it indicates a relatively homogeneous and dense formation. The assessment module outputs a quantified fracture development degree index, with a value ranging from 0 to 1, where a larger value indicates a higher degree of fracture development. This assessment result is simultaneously input as a key parameter into the feedforward channel control subsystem and the dynamic weight fusion calculation subsystem, providing geological basis for subsequent control decisions.

[0022] The following steps are followed for implementing the dual-liquid grouting pressure stabilization compensation method based on multi-parameter control.

[0023] The first step, S1, involves the acquisition and preprocessing of real-time pressure data. The purpose of step S1 is to obtain accurate, stable, and low-latency real-time grouting pressure values, providing a reliable data foundation for subsequent feedback control and weighted fusion. The specific implementation process is as follows.

[0024] Step S101: Acquire the raw pressure signal and perform analog-to-digital conversion. Install high-frequency response pressure sensors at the grouting pump outlet, the middle section of the grouting pipeline, and the grouting hole to form a three-point pressure monitoring network. The sampling frequency of the pressure sensors is not less than 500Hz, the resolution is not less than 0.01MPa, and the signal transmission delay is not more than 1ms.

[0025] The raw pressure signal output from the pressure sensor first passes through a hardware low-pass filter. The cutoff frequency of the hardware low-pass filter is set to half the sampling frequency to eliminate high-frequency noise components above the Nyquist frequency. The analog signal after hardware filtering is immediately converted from analog to digital. The analog-to-digital conversion has a precision of 16 bits and a sampling period of 2ms, outputting a digital pressure signal.

[0026] Step S102: Perform two-stage digital filtering. The digital pressure signal output after analog-to-digital conversion enters the first-stage digital filtering unit. The first-stage digital filtering unit uses a finite impulse response (FIR) filter for band-limited filtering. The FIR filter has a passband cutoff frequency of 100Hz, a stopband cutoff frequency of 200Hz, and a stopband attenuation of not less than 40dB.

[0027] The signal processed by the first-stage digital filtering unit then enters the second-stage adaptive filtering unit. The second-stage adaptive filtering unit operates based on the minimum mean square error criterion and is used to suppress 50Hz power frequency interference and its harmonic components. After the two stages of digital filtering are connected in series, the processed pressure signal is output.

[0028] Step S103: Calculate the pressure change rate and construct a two-dimensional pressure state vector. Perform a time-domain difference operation between the pressure signal processed in step S102 and the pressure signal at the previous moment. The result of the time-domain difference operation is the pressure change rate at the current moment.

[0029] Then, the current pressure value and the current rate of pressure change are combined to form a two-dimensional pressure state vector. The two-dimensional pressure state vector reflects both the instantaneous magnitude of the pressure and its changing trend.

[0030] Step S104: Optimal state estimation is performed based on the Kalman filter, and the real-time pressure value is output. The two-dimensional pressure state vector constructed in step S103 is input into the Kalman filter. The operation of the Kalman filter is based on the following state-space model: Equations of state: ; Observation equation: ; in: Indicates the first The system state vector at time t is a two-dimensional vector consisting of the pressure value and the rate of pressure change in step S1. Let be the state transition matrix, describing the system state from the _____ to the _____. Time to the The evolutionary pattern of time; This represents process noise, indicating the inherent uncertainty of the state-space model itself. For the first The observed value at time, i.e. the pressure signal after processing in step S102; This is the observation matrix, used to map the real state to the observation space; The noise level represents the measurement error of the pressure sensor.

[0031] The Kalman filter operates recursively through two steps: prediction and update. In the prediction step, the state at the current time step is predicted using the optimal estimate from the previous time step.

[0032] In the update step, the predicted value is weighted and corrected based on the actual observation value at the current moment to obtain the optimal state estimate for the current moment. The estimated pressure value output by the Kalman filter is the final real-time grouting pressure value used for control.

[0033] Simultaneously, the Kalman filter automatically updates its internal state covariance matrix and observation covariance matrix to prepare for the estimation calculation at the next time step. The aforementioned real-time grouting pressure value is synchronously output to the feedback channel control subsystem and the dynamic weight fusion calculation subsystem at a frequency of 10Hz.

[0034] Step S1 completes the entire processing flow from acquiring the raw pressure signal to outputting a high-precision real-time pressure value. Specifically, a hardware low-pass filter and two-stage digital filtering eliminate high-frequency noise and power frequency interference; time-domain differential computation extracts the pressure change rate; and a Kalman filter performs optimal estimation of the pressure value based on a state-space model. The final output real-time pressure value features low latency, high stability, and high accuracy, providing data support for subsequent pressure deviation calculations in the feedback channel and dynamic weight fusion.

[0035] For step S2, a dual-channel control architecture is constructed. The feedback channel uses a proportional-integral-derivative (PID) control algorithm to achieve real-time correction of pressure deviation, while the feedforward channel uses a formation characteristic correlation model identified by recursive least squares to achieve advance prediction and compensation of pressure fluctuations. The outputs of the two channels are fused in subsequent steps, specifically as follows.

[0036] Step S201: Construct the proportional-integral-derivative (PID) control law for the feedback channel. The control logic of the feedback channel is implemented using the PID algorithm. The control law expression of the PID algorithm is: in: Indicates the first Feedback correction amount at the sampling time; Indicates the first Pressure deviation at the sampling time, which is the difference between the target pressure and the real-time pressure; Indicates the first The scaling factor at the sampling time; Indicates the integral coefficient; This represents the differential coefficient.

[0037] proportionality coefficient An adaptive tuning strategy is adopted. The tuning rules of the adaptive tuning strategy are dynamically adjusted according to the magnitude and trend of the pressure deviation. When the absolute value of the pressure deviation is greater than 0.5 MPa, the proportionality coefficient... Set to a larger value to improve response speed; When the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa, the proportionality coefficient... Set to a medium value to balance response speed and control precision; When the absolute value of the pressure deviation is less than 0.1 MPa, the proportionality coefficient... Set to a smaller value to avoid overshoot.

[0038] Integral coefficient The settings need to balance eliminating steady-state errors and preventing integral saturation. The value ranges from 0.01 to 0.05, and the specific value is determined on-site based on the geological characteristics and grouting process requirements.

[0039] Differential coefficients Its function is to predict pressure change trends and provide damping. The value ranges from 0.1 to 0.5. When a rapid change in pressure is detected, the derivative action is enhanced to suppress overshoot.

[0040] Control output of feedback channel After being processed by limiting, the output is sent to the dynamic weight fusion calculation subsystem.

[0041] Step S202: Constructing the Formation Characteristic Correlation Model for the Feedforward Channel. The control logic of the feedforward channel relies on a historical correlation model between formation characteristic parameters and pressure fluctuations. The correlation model is identified and updated online using the recursive least squares method. The model structure of the correlation model is a multi-input single-output linear regression model with time delay, and its mathematical expression is: in: The first term of the feedforward channel prediction Pressure fluctuation at the sampling time; This represents the permeability coefficient deviation, which is the difference between the current measured value and the design reference value. This indicates the deviation of the index representing the degree of fracture development; This indicates the change in pressure at the previous moment. , , This is a vector of model parameters that is updated over time.

[0042] The parameter update formula for recursive least squares includes a forgetting factor. and update the gain matrix Forgetting factor The value range is between 0.95 and 0.99, the forgetting factor. Its purpose is to enhance the algorithm's ability to track non-stationary processes. As grouting operations continue, the associated model continuously accumulates on-site data, and the model parameter vector... , , As the feedforward channel gradually converges to a steady-state value, its prediction accuracy improves.

[0043] Step S203: Calculate the feedforward compensation amount; the feedforward compensation amount output by the feedforward channel. It includes two parts: flow compensation component and ratio compensation component.

[0044] The flow compensation component is calculated based on the magnitude of the deviation of the permeability coefficient from the design value. The formula for calculating the flow compensation component is as follows: ,in Here is the flow compensation coefficient. The values ​​are determined based on field test calibration.

[0045] The proportion compensation component is calculated based on the degree of formation fracture development. The formula for calculating the proportion compensation component is as follows: ,in This is the proportioning compensation coefficient. The value is determined based on the slurry gel characteristic curve.

[0046] Feedforward compensation It can be directly output to the dynamic weight fusion calculation subsystem, and preventive adjustment can be achieved without waiting for the generation of pressure deviation.

[0047] In summary, step S2 completes the independent construction of the feedback channel and the feedforward channel. The feedback channel uses a proportional-integral-derivative (PID) control algorithm and its adaptive proportional coefficient tuning strategy to achieve real-time correction of pressure deviation. The feedforward channel uses the recursive least squares method to identify the correlation model between formation characteristic parameters and pressure fluctuations online, and calculates the flow compensation component and the proportioning compensation component accordingly to achieve advanced prediction of pressure fluctuations. The outputs of the two channels are the feedback correction amounts, respectively. and feedforward compensation The two will be integrated in step S3 using a dynamic weight fusion algorithm.

[0048] For step S3, the weight ratio of feedback correction and feedforward compensation in the comprehensive control command is adaptively adjusted according to the current operating conditions to achieve coordinated control of the feedback channel and the feedforward channel. This is carried out according to the following steps.

[0049] Step S301: Establish the dynamic weight fusion calculation expression. The dynamic weight fusion calculation expression is as follows: in: Indicates the first Comprehensive control instructions at the sampling time; Represents the dynamic weighting coefficient of the feedback channel; Indicates the first Feedback correction amount at sampling time, feedback correction amount Calculated by step S201; This represents the dynamic weighting coefficient of the feedforward channel; Indicates the first Feedforward compensation at sampling time, feedforward compensation It is calculated by step S203.

[0050] Dynamic weighting coefficients of the feedback channel Dynamic weighting coefficients of the feedforward channel The following constraints must be met: .

[0051] Step S302: Layering weight allocation is performed based on the absolute value of the pressure deviation and the formation complexity. The adaptive adjustment strategy of the dynamic weight coefficients implements layering control based on the absolute value of the pressure deviation and the formation complexity. The formation complexity is determined by the fracture development degree index. Quantification, fracture development degree index The value ranges from 0 to 1, and the larger the value, the higher the degree of fracture development.

[0052] First, when the absolute value of the pressure deviation is in the range of 0 to 0.1 MPa and the crack development index... When the value is less than 0.3, the stratum complexity is judged as simple.

[0053] At this point, the weight allocation between the feedforward channel and the feedback channel adopts a first preset ratio: the dynamic weight coefficient of the feedback channel. Set to 0.7, the dynamic weighting coefficient of the feedforward channel. The setting is 0.3. The first preset ratio indicates that, under relatively stable operating conditions, feedback control is the primary method to maintain control accuracy, while feedforward control is used as a secondary method to provide fine-tuning.

[0054] Second, when the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa and the crack development index... When the value is between 0.3 and 0.7, the stratigraphic complexity is classified as moderate.

[0055] At this point, the weight allocation between the feedforward channel and the feedback channel adopts a second preset ratio: the dynamic weight coefficient of the feedback channel. Set to 0.5, the dynamic weighting coefficient of the feedforward channel. The value is set to 0.5. This second preset ratio indicates that, under moderately complex operating conditions, feedback control and feedforward control are equally important and work together.

[0056] Third, when the absolute value of the pressure deviation is greater than 0.5 MPa and the fracture development degree index... When the value is greater than 0.7, the stratigraphic complexity is judged as complex.

[0057] At this point, the weight allocation between the feedforward channel and the feedback channel adopts a third preset ratio: the dynamic weight coefficient of the feedback channel. Set to 0.3, the dynamic weighting coefficient of the feedforward channel. The setting is 0.7. The third preset ratio indicates that under complex operating conditions, feedforward control plays a dominant role, utilizing formation sensing information for preventative adjustments, while feedback control serves as a safety fallback.

[0058] Step S303: Adjust the dynamic weighting coefficient in real time according to the pressure deviation change rate. Based on the above-mentioned hierarchical weighting allocation, adjust the dynamic weighting coefficient of the feedback channel. Dynamic weighting coefficients of the feedforward channel It also makes real-time corrections based on the rate of change of pressure deviation.

[0059] When a rapid increase in pressure deviation is detected, the dynamic weighting coefficient of the feedforward channel... Temporarily increase the current configuration by 10% to 20%, while also adjusting the dynamic weighting coefficient of the feedback channel. The corresponding reduction is made to enhance the response speed and disturbance rejection capability of the control system.

[0060] Through steps S301 to S303, the adaptive adjustment of the dynamic weighting coefficients is completed. The adaptive adjustment mechanism of the dynamic weighting coefficients enables the comprehensive control command... Feedback correction With feedforward compensation The proportion changes dynamically with the operating conditions, thereby achieving global optimization of the control effect.

[0061] Step S304: Construct the information structure of the integrated control command; integrated control command It includes two dimensions of control information: flow regulation information and ratio adjustment information.

[0062] Flow rate adjustment information is expressed as a percentage change in flow rate. A positive percentage change indicates that the total output flow rate of the two liquids needs to be increased; a negative percentage change indicates that the total output flow rate of the two liquids needs to be decreased.

[0063] The proportioning adjustment information is expressed as a proportioning adjustment coefficient for the volumetric flow rates of solution A and solution B. The baseline value of the proportioning adjustment coefficient is 1. When the proportioning adjustment coefficient is greater than 1, it indicates that the proportion of solution B needs to be increased; when the proportioning adjustment coefficient is less than 1, it indicates that the proportion of solution B needs to be decreased.

[0064] Comprehensive control instructions Updated at a frequency of 20Hz and simultaneously sent to the dual-liquid ratio dynamic adjustment module and the dual-liquid pump group execution subsystem.

[0065] Step S3 establishes the dynamic weight fusion algorithm. The fusion calculation expression in step S301 will feed back the correction amount. With feedforward compensation Synthesized into a comprehensive control command Step S302 is based on the absolute value of the pressure deviation and the crack development degree index. The operating conditions are divided into three levels: simple, medium, and complex, and a preset weight ratio is assigned to each level. Step S303 adjusts the dynamic weight coefficient in real time based on the pressure deviation change rate.

[0066] Finally, in step S4, the integrated control command generated in step S3 is used to drive the dual-liquid pump group execution subsystem and switch the control mode according to the pressure deviation level to complete the closed-loop stable control of the dual-liquid grouting pressure. This is carried out according to the following steps.

[0067] Step S401: Configure the dual-liquid pump set execution subsystem and slurry parameters. The dual-liquid pump set execution subsystem includes two independent pumping units: a liquid A pump and a liquid B pump. The liquid A pump is responsible for conveying cement slurry, and the liquid B pump is responsible for conveying water glass solution.

[0068] The preparation parameters of the cement slurry are as follows: the water-cement ratio is controlled between 0.6 and 1.0, and the specific value of the water-cement ratio is determined according to the requirements of the formation consolidation strength; the cement grade is 42.5 ordinary Portland cement; the density of the cement slurry is controlled within the range of 1.45 to 1.65 grams per cubic centimeter.

[0069] The preparation parameters of the water glass solution are as follows: the Baumé degree is controlled between 30 and 45, and the specific value of the Baumé degree is determined according to the formation gelation time requirements; the modulus of the water glass is controlled between 2.8 and 3.3; the density of the water glass solution is controlled between 1.26 and 1.45 grams per cubic centimeter.

[0070] The initial volumetric flow rate ratio of the two liquids is controlled within the range of 1:0.3 to 1:1. The specific value of the initial volumetric flow rate ratio is determined according to the formation characteristics: when the formation permeability coefficient of the grouting area is large or the degree of fracture development is high, the initial volumetric flow rate ratio tends to increase the proportion of water glass to shorten the gelation time; when the formation of the grouting area is relatively dense, the initial volumetric flow rate ratio tends to decrease the proportion of water glass to prolong the gelation time and improve the consolidation strength.

[0071] Step S402: Configure the dual-liquid ratio dynamic adjustment module, which is set in the dual-liquid pump group control architecture. The input of the dual-liquid ratio dynamic adjustment module receives comprehensive control commands from the dynamic weight fusion calculation subsystem. The output of the dual-liquid ratio dynamic adjustment module is connected to the frequency converters of the A-liquid pump and the B-liquid pump.

[0072] The dual-liquid ratio dynamic adjustment module integrates two functional modules: a ratio calculation unit and a flow distribution unit.

[0073] The proportioning calculation unit calculates the target proportion value for the current moment based on the proportioning adjustment information in the comprehensive control command. The calculation logic of the proportioning calculation unit follows the following rules.

[0074] When the comprehensive control command includes a positive flow rate adjustment and the increase in the positive flow rate adjustment exceeds 5%, the proportion of liquid B will be increased by 2% to 5% based on the current ratio to accommodate the increased slurry diffusion range caused by the increased pressure.

[0075] When the comprehensive control command includes a negative flow rate adjustment and the reduction of the negative flow rate adjustment exceeds 5%, the proportion of liquid B will be reduced by 2% to 5% based on the current ratio to extend the gel time and ensure that the slurry can still fully fill the target area under lower flow conditions.

[0076] When the flow rate adjustment in the comprehensive control command is within the fine-tuning range of ±5%, the ratio remains unchanged to maintain control stability.

[0077] The flow distribution unit calculates the output flow rates of pumps A and B based on the target ratio and the flow regulation information in the integrated control command. The calculation formula for the flow distribution unit is: in: Indicates the target flow rate of the liquid A pump; Indicates the target flow rate of the B-liquid pump; Indicates the total output flow rate of the two liquids; This indicates the current target ratio value. This represents the ratio of the volumetric flow rates of liquid B to that of liquid A.

[0078] The calculated target flow rate of the liquid A pump And the target flow rate of the ethyl alcohol pump The speed setpoint signal of the pump controller is used to adjust the speed of pump A and pump B by the frequency converter, thereby regulating the flow rate.

[0079] Step S403: Switch the control mode according to the pressure deviation level. The pressure control effect enters different control modes depending on the pressure deviation level. Pressure deviation This is the difference between the target pressure and the real-time pressure.

[0080] First, when pressure deviation When the pressure exceeds 0.5 MPa, the pressure deviation reaches the first preset threshold and enters the rapid adjustment mode.

[0081] In fast adjustment mode, the feedforward dynamic weight coefficients in the dynamic weight fusion algorithm The pressure is temporarily increased to above 0.8, and the integral effect is temporarily suppressed to avoid overshoot caused by integral saturation. The adjustment range of the pump flow rate is set to 1.5 times that of the normal mode to bring the pressure back to the target range in the shortest possible time.

[0082] Second, when pressure deviation When the pressure deviation is between 0.1MPa and 0.5MPa, it falls between the first preset threshold and the second preset threshold, thus entering the fine adjustment mode.

[0083] In the fine adjustment mode, the integral action is used to eliminate steady-state error, the adjustment range of pump flow rate adopts a gradual strategy to avoid overshoot, and the ratio adjustment is optimized according to the formation characteristics.

[0084] Third, when pressure deviation When the pressure deviation is less than 0.1 MPa, the pressure deviation reaches the second preset threshold and enters the steady-state maintenance mode.

[0085] In steady-state mode, pressure is maintained by a small flow rate adjustment, the ratio is kept constant, and the pressure fluctuation is controlled within ±0.05 MPa of the target pressure.

[0086] Step S4 achieves precise pressure control through dual-liquid synergy. By configuring the parameters and initial ratio of the cement grout and water glass solution, the dual-liquid ratio dynamic adjustment module converts the comprehensive control command into the target flow rates of pumps A and B, which are then executed by the frequency converter. Simultaneously, based on the pressure deviation level, it automatically switches between three control modes: rapid adjustment, fine adjustment, or steady-state maintenance, achieving closed-loop stable control of the grouting pressure. In summary, steps S1 to S4 together constitute the complete technical flow of the dual-liquid grouting pressure stabilization compensation method of this invention.

[0087] To facilitate understanding, an example is provided. Assume the grouting operation area is a tunnel project traversing a fault fracture zone. The measured permeability coefficient of this section is 8 × 10⁻⁴ cm / s, the fracture development index is assessed at 0.65, and the geological conditions are classified as moderately complex. The target grouting pressure is set at 3.5 MPa, and the gel time is controlled to be 45 to 60 seconds. The initial two-component mix ratio is set at 1:0.6, the cement grout water-cement ratio is 0.8, and the water glass Baumé degree is 38.

[0088] After the grouting operation is started, the pressure sensor collects the grouting pressure signal in real time. The real-time pressure value obtained after filtering is 2.8 MPa, which has a positive deviation of 0.7 MPa from the target pressure of 3.5 MPa. Since the deviation exceeds the first preset threshold of 0.5 MPa, the system enters a rapid adjustment mode. The feedback channel calculates the feedback correction amount based on the deviation, with a larger proportional term output to provide a rapid response, while the integral term is temporarily suppressed.

[0089] The feedforward channel predicts pressure fluctuation trends based on information output from the formation permeability coefficient and fracture development assessment module. A permeability coefficient higher than the design benchmark indicates strong formation grout absorption capacity, necessitating an appropriate increase in grouting flow rate. Simultaneously, a higher degree of fracture development requires a slight increase in the water glass ratio to shorten gelation time and prevent excessive grout diffusion. Both the flow rate compensation component and the proportion compensation component in the feedforward compensation are positive. Based on the condition of a large pressure deviation, the dynamic weight fusion calculation subsystem temporarily increases the feedforward dynamic weight coefficient to 0.85 and sets the feedback dynamic weight coefficient to 0.15. The calculated comprehensive control command includes a 15% increase in positive flow rate adjustment and a 3% increase in the proportion of ethyl acetate.

[0090] After receiving the comprehensive control command, the dual-liquid ratio dynamic adjustment module calculates that the total output flow rate of the two liquids needs to be increased from the initial value of 60 liters per minute to 69 liters per minute, while the ratio is adjusted from 1:0.6 to 1:0.62. The target flow rate of the A liquid pump is calculated to be 42.6 liters per minute, and the target flow rate of the B liquid pump is calculated to be 26.4 liters per minute. After receiving the target flow rate signal, the pump controller adjusts the pump speed through the frequency converter to achieve precise flow rate regulation. The pressure sensor continues to monitor the changes in grouting pressure, and the pressure value gradually increases from 2.8 MPa.

[0091] After approximately 8 seconds of adjustment, the real-time pressure rose to 3.3 MPa, narrowing the deviation from the target pressure of 3.5 MPa to 0.2 MPa, and automatically switched from rapid adjustment mode to fine adjustment mode. In fine adjustment mode, the integral term resumed its normal function to eliminate steady-state error, and the dynamic weighting coefficient was adjusted to a balanced configuration of feedback weight 0.5 and feedforward weight 0.5. The feedback channel calculated the feedback correction amount based on the moderate deviation of 0.2 MPa, and the feedforward channel updated the feedforward compensation amount based on continuous monitoring of formation parameters. The comprehensive control command was calculated as a 2% increase in flow rate and a further 1% increase in the proportion of liquid B in the mix ratio. The total output flow rate of the two liquids was finely adjusted from 69 liters per minute to 70.4 liters per minute, and the mix ratio was adjusted to 1:0.63.

[0092] After approximately 12 seconds of adjustment, the real-time pressure value stabilized at around 3.5 MPa, with fluctuations controlled within ±0.03 MPa. The pressure deviation was determined to be less than the second preset threshold of 0.1 MPa, and the system automatically switched to steady-state maintenance mode. In steady-state maintenance mode, the total output flow rate of the two liquids was fine-tuned in increments of 0.5 liters per minute, while the ratio remained constant at 1:0.63. The control task was to maintain pressure stability and adaptively compensate for minor changes in formation characteristics.

[0093] During subsequent grouting operations, when the stratum characteristic sensing unit detected an increase in the fracture development degree index from 0.65 to 0.72, the feedforward channel immediately calculated an increase in the mix proportion compensation component. The dynamic weighted fusion calculation subsystem automatically output a mix proportion adjustment command based on the temporary increase in the feedforward weight, increasing the proportion of liquid B from 1:0.63 to 1:0.66 to accommodate the risk of shortened gel time due to increased fracture development. When the pressure sensor detected slight fluctuations in pressure due to geological changes, the feedback channel instantly calculated the feedback correction amount and made fine adjustments to maintain continuous pressure stability. Throughout the grouting process, the pressure control accuracy remained within ±0.05 MPa of the target pressure, and the gel time was controlled within the range of 48 to 55 seconds, meeting the design requirements.

[0094] In addition, in some application scenarios, the geological conditions in the grouting operation area exhibit significant heterogeneity, with large differences in geological parameters between different grouting sections. In such cases, a segmented dynamic proportioning control strategy is required to compensate for grouting pressure.

[0095] The main difference from the aforementioned technical solutions lies in the configuration of the formation characteristic sensing unit and the control strategy of the dual-liquid ratio dynamic adjustment module. In the segmented dynamic ratio control strategy, the formation characteristic sensing unit includes multiple distributed permeability coefficient sensors and multiple distributed fracture development degree assessment modules. Each sensor and assessment module is set at different segment nodes of the grouting pipeline to achieve refined sensing of formation parameters along the grouting path. The permeability coefficient and fracture development degree data of each segment are aggregated by the data acquisition unit and interpolated according to spatial location to generate a formation parameter distribution curve along the grouting path. After the distribution curve is input to the feedforward channel control subsystem, the calculation of the feedforward compensation not only considers the formation parameters at the current grouting location but also predicts the upcoming changes in formation conditions based on the advancement direction of the grouting front, thus achieving advanced adjustment of the feedforward compensation.

[0096] Under the segmented dynamic proportioning control strategy, the dual-liquid proportioning dynamic adjustment module adopts a multi-level control architecture. The first level of the module is the overall proportioning layer for the grouting path, which determines the overall proportioning baseline value based on the average formation parameters of the grouting path. The second level is the segment proportioning adjustment layer, which calculates the segment proportioning adjustment amount based on the deviation of the formation parameters of each segment from the average parameters. The third level is the real-time proportioning fine-tuning layer, which performs fine-tuning of the proportioning based on pressure feedback information. The proportioning adjustment commands from each level are weighted and fused before being output to the dual-liquid pump group execution subsystem. The weighting coefficients for the weighting fusion can be preset, for example, a weight of 0.5 for the overall proportioning layer, 0.3 for the segment proportioning adjustment layer, and 0.2 for the real-time proportioning fine-tuning layer. The weights of each level can also be dynamically adjusted according to the degree of formation heterogeneity. Through this layered weighted fusion, both spatial and temporal accuracy of the proportioning control are guaranteed.

[0097] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects.

[0098] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A double-liquid grouting pressure stabilizing compensation method based on multi-parameter regulation, characterized in that, Includes the following steps: Real-time grouting pressure values ​​are obtained, and a dual-channel control architecture is constructed that coordinates the feedback channel and the feedforward channel. The feedback channel calculates the deviation between the real-time grouting pressure value and the target pressure based on the proportional-integral-derivative control algorithm, and generates a feedback correction amount. The feedforward channel is based on the formation characteristic correlation model of recursive least squares method. It predicts the pressure fluctuation trend according to the formation permeability coefficient deviation and fracture development degree index deviation, and generates a feedforward compensation quantity that includes flow compensation component and ratio compensation component. Using a dynamic weighted fusion algorithm, the weight ratio of the feedback correction and the feedforward compensation is adaptively adjusted according to the current absolute value of the pressure deviation and the formation complexity, and synthesized into a comprehensive control command. The comprehensive control command includes flow regulation information and ratio adjustment information. The dual-liquid pump group execution subsystem is driven by the comprehensive control command, and the control mode is switched according to the pressure deviation between the real-time grouting pressure value and the target pressure to complete the closed-loop stable control of the dual-liquid grouting pressure.

2. The method according to claim 1, wherein, The step of obtaining the real-time grouting pressure value specifically includes: High-frequency response pressure sensors are installed at the outlet of the grouting pump, the middle section of the grouting pipeline, and the grouting hole to form a three-point pressure monitoring network and collect raw pressure signals. The original pressure signal is sequentially passed through a hardware low-pass filter, a finite impulse response filter for band-limited filtering, and an adaptive filtering unit based on the minimum mean square error criterion to suppress power frequency interference, and then outputs the pressure signal processed by the adaptive filtering unit. The pressure signal processed by the adaptive filtering unit is subjected to time-domain difference operation with the pressure signal at the previous moment to calculate the pressure change rate, and the pressure value at the current moment is combined with the pressure change rate to form a two-dimensional pressure state vector. The two-dimensional pressure state vector is input into a Kalman filter, and the optimal state is estimated based on the state-space model to output the real-time grouting pressure value.

3. The method according to claim 1, wherein, In the step of calculating the deviation between the real-time grouting pressure value and the target pressure based on the proportional-integral-derivative control algorithm and generating the feedback correction amount, the feedback channel is as follows: The control law expression for the proportional-integral-derivative (PID) control algorithm is: ,in The feedback correction amount, The pressure deviation is mentioned above. The integral coefficient is... These are the differential coefficients; proportionality coefficient An adaptive tuning strategy is adopted: when the absolute value of the pressure deviation is greater than 0.5 MPa, the proportional coefficient... Set to a larger value; when the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa, the proportional coefficient... Set to a medium value; when the absolute value of the pressure deviation is less than 0.1 MPa, the proportionality coefficient... Set to a smaller value.

4. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, The feedforward channel is based on a formation characteristic correlation model using the recursive least squares method. It predicts pressure fluctuation trends based on formation permeability coefficient deviation and fracture development degree index deviation, and generates a feedforward compensation quantity that includes flow compensation and proportion compensation components. The stratigraphic characteristic correlation model is a multi-input single-output linear regression model with time delay. The mathematical expression of the multi-input single-output linear regression model with time delay is: ,in For the predicted pressure fluctuation amount, This refers to the deviation in the formation permeability coefficient. This refers to the deviation of the fracture development degree index. This represents the pressure change at the previous moment. , , This is the model parameter vector; The parameter update formula for the recursive least squares method includes a forgetting factor. and update the gain matrix The forgetting factor The value range is between 0.95 and 0.99; The flow compensation component in the feedforward compensation is calculated based on the magnitude of the deviation of the permeability coefficient from the design value. The calculation formula for the flow compensation component is as follows: ,in This is the flow compensation coefficient; The proportionate compensation component in the feedforward compensation is calculated based on the degree of formation fracture development, and the calculation formula for the proportionate compensation component is as follows: ,in This is the matching compensation coefficient.

5. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, In the step of using a dynamic weighted fusion algorithm to adaptively adjust the weight ratio of the feedback correction and the feedforward compensation based on the current absolute value of the pressure deviation and the complexity of the formation, and synthesizing them into a comprehensive control command: The calculation expression for the dynamic weight fusion algorithm is as follows: ,in The comprehensive control command, The dynamic weighting coefficients for the feedback channel. The feedback correction amount, These are the dynamic weighting coefficients for the feedforward channel. The feedforward compensation amount is given, and satisfies the following conditions: ; When the absolute value of the pressure deviation is in the range of 0 to 0.1 MPa and the fracture development index When the value is less than 0.3, set the dynamic weighting coefficient of the feedback channel and the dynamic weighting coefficient of the feedforward channel. ; When the absolute value of the pressure deviation is in the range of 0.1 MPa to 0.5 MPa and the fracture development index When the value is between 0.3 and 0.7, the dynamic weighting coefficient of the feedback channel is set. The dynamic weighting coefficient of the feedforward channel ; When the absolute value of the pressure deviation is greater than 0.5 MPa and the fracture development degree index When the value is greater than 0.7, the dynamic weighting coefficient of the feedback channel is set. The dynamic weighting coefficient of the feedforward channel ; Furthermore, when a rapid increase in the pressure deviation is detected, the dynamic weighting coefficient of the feedforward channel is adjusted based on the above configuration. The dynamic weighting coefficient of the feedback channel is temporarily increased by 10% to 20%, while the dynamic weighting coefficient of the feedback channel is reduced accordingly.

6. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, The integrated control command includes flow regulation information and ratio adjustment information: The flow rate adjustment information is expressed as a percentage change in flow rate. When the percentage change in flow rate is positive, it indicates that the total output flow rate of the two liquids needs to be increased. When the percentage change in flow rate is negative, it indicates that the total output flow rate of the two liquids needs to be decreased. The ratio adjustment information is expressed in the form of a ratio adjustment coefficient of volume flow rate of liquid A and liquid B. The base value of the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is 1. When the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is greater than 1, it means that the proportion of liquid B needs to be increased. When the ratio adjustment coefficient of volume flow rate of liquid A and liquid B is less than 1, it means that the proportion of liquid B needs to be decreased.

7. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, In the step of driving the dual-liquid pump group execution subsystem using the comprehensive control command, the comprehensive control command is received through the dual-liquid ratio dynamic adjustment module, which integrates a ratio calculation unit and a flow distribution unit. The proportion calculation unit calculates the target proportion value at the current moment based on the proportion adjustment information in the comprehensive control instruction. The calculation logic of the proportion calculation unit is as follows: when the comprehensive control instruction includes a positive flow rate adjustment and the increase of the positive flow rate adjustment exceeds 5%, the proportion of liquid B is increased by 2% to 5% based on the current proportion. When the comprehensive control command includes a negative flow rate adjustment and the reduction of the negative flow rate adjustment exceeds 5%, the proportion of liquid B will be reduced by 2% to 5% based on the current ratio; The flow distribution unit calculates the target flow rate of the liquid A pump based on the target ratio value at the current moment and the flow adjustment information in the comprehensive control command, using the following formula. And the target flow rate of the ethyl alcohol pump : , ,in This represents the total output flow rate of the two liquids. The target allocation value at the current time. This represents the ratio of the volumetric flow rates of liquid B to that of liquid A.

8. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, In the step of switching the control mode based on the magnitude of the pressure deviation between the real-time grouting pressure value and the target pressure: When the pressure deviation When the pressure exceeds 0.5 MPa, a fast adjustment mode is entered. In this fast adjustment mode, the dynamic weighting coefficient of the feedforward channel is adjusted. Temporarily increase to above 0.8, temporarily suppress integral action to avoid integral saturation, and set the adjustment range of pump flow rate to 1.5 times that of normal mode; When the pressure deviation When the pressure is between 0.1MPa and 0.5MPa, it enters the fine adjustment mode. In the fine adjustment mode, the integral action is used to eliminate steady-state error, and the adjustment range of the pumping flow rate adopts a gradual strategy to avoid overshoot. When the pressure deviation When the pressure is less than 0.1 MPa, the system enters a steady-state maintenance mode. In this mode, the pressure is maintained by a small flow rate adjustment, the ratio is kept constant, and the pressure fluctuation is controlled within ±0.05 MPa of the target pressure.

9. The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control according to claim 1, characterized in that, It also includes a dynamic allocation control strategy for different zones: The formation characteristic sensing unit includes multiple distributed permeability coefficient sensors and multiple distributed fracture development degree assessment modules. The multiple distributed permeability coefficient sensors and multiple distributed fracture development degree assessment modules are respectively set on different section nodes of the grouting pipeline. The permeability coefficient data and fracture development degree index data of each section are summarized by the data acquisition unit and interpolated according to spatial location to generate formation parameter distribution curves along the grouting path. The dual-liquid ratio dynamic adjustment module adopts a multi-level control architecture: the first level is the overall grouting path ratio layer, which determines the overall ratio base value based on the average formation parameters of the formation parameter distribution curve along the grouting path; the second level is the section ratio adjustment layer, which calculates the section ratio adjustment amount based on the degree of deviation between the formation parameters of each section and the average formation parameters. The third level is the real-time ratio fine-tuning layer, which performs fine-tuning of the ratio based on pressure feedback information; The proportioning adjustment commands of the overall grouting path proportioning layer, the section proportioning adjustment layer, and the real-time proportioning fine-tuning layer are weighted and fused before being output to the dual-liquid pump group execution subsystem. The weight of the overall grouting path proportioning layer is preset to 0.5, the weight of the section proportioning adjustment layer is preset to 0.3, and the weight of the real-time proportioning fine-tuning layer is preset to 0.

2.

10. A dual-liquid grouting pressure stabilization and compensation system based on multi-parameter control, characterized in that, The dual-liquid grouting pressure stabilization and compensation method based on multi-parameter control, applicable to any one of claims 1 to 9, wherein the dual-liquid grouting pressure stabilization and compensation system based on multi-parameter control comprises: The dual-liquid pump set execution subsystem includes a liquid A pump for conveying cement slurry and a liquid B pump for conveying water glass solution. The speed of liquid A pump and liquid B pump is adjusted by independent variable frequency drive controllers. The formation characteristic sensing unit includes a permeability sensor for real-time measurement of formation permeability coefficient, and a fracture development degree assessment module for quantitatively evaluating the fracture development degree index based on the pressure response curve characteristics during grouting. The real-time pressure data acquisition subsystem includes high-frequency response pressure sensors installed at the outlet end of the grouting pump, the middle section of the grouting pipeline, and the grouting orifice. The high-frequency response pressure sensors are used to acquire raw pressure signals and perform analog-to-digital conversion. The feedback channel control subsystem is equipped with a proportional-integral-derivative control algorithm, which is used to calculate the feedback correction amount based on the deviation between the real-time grouting pressure value and the target pressure. The feedforward channel control subsystem embeds a formation characteristic correlation model based on the recursive least squares method, which is used to calculate the feedforward compensation amount including flow compensation component and ratio compensation component based on the formation permeability coefficient deviation and fracture development degree index deviation. The dynamic weighted fusion calculation subsystem is used to dynamically adjust the weight ratio of the feedback correction amount and the feedforward compensation amount according to the current absolute value of the pressure deviation and the formation complexity, and fuse them to generate a comprehensive control command that includes flow regulation information and ratio adjustment information. The dual-liquid ratio dynamic adjustment module is connected to the dynamic weight fusion calculation subsystem and the dual-liquid pump group execution subsystem, respectively. The dual-liquid ratio dynamic adjustment module integrates a ratio calculation unit for calculating the target ratio value and a flow distribution unit for calculating the target flow rate of pump A and pump B.

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