A method for monitoring and processing the risk early warning of grouting slurry spouting of thin-bed rock separation layer

Abstract

The application discloses a method for early warning, monitoring and processing of grouting risk of thin-bed rock separation layer, and belongs to the field of mine safety mining and grouting engineering; the method constructs an in-situ test space by constructing an independent monitoring borehole and sealing the borehole at the interface; a water pressure test is started before grouting, a sliding time window is used to identify a steady state and to obtain a dynamic initial pressure benchmark value; the borehole pressure is collected in real time during grouting, and the pressure amplitude and the change rate characteristics are calculated; the two characteristics are input into a finite state machine logic, and a graded early warning state word is output after anti-jitter accumulation by a counter; a control system drives a frequency converter to execute closed-loop pressure reduction or triggers emergency shutdown and pipeline pressure relief according to the early warning state word. The application eliminates early warning distortion caused by geological differences and equipment interference, and realizes accurate identification and automatic intervention of grouting risk.

Description

Technical Field

[0001] This invention belongs to the field of safe mining and grouting engineering, specifically relating to a method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting. Background Technology

[0002] Currently, in the coal mining industry, delamination grouting is a green mining technology. However, when using delamination grouting for filling in areas with thin bedrock as the basic geological condition, due to the special geological conditions, the grout can easily seep into the bedrock interface through cracks or weak zones during the grouting process in thin bedrock sections, creating a risk of grout leakage.

[0003] Existing technologies include online monitoring methods, but these can only indicate that grout leakage has occurred, not pinpoint the exact stratum where the leakage is occurring, especially in intermediate strata where detection is extremely difficult. Therefore, the early warning capability for grout leakage at thin bedrock interfaces is weak, hindering early detection and timely intervention.

[0004] Therefore, a method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting is proposed. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for early warning monitoring and handling of grout leakage risks in thin bedrock delamination grouting, thus solving the problems in existing technologies.

[0006] The objective of this invention can be achieved through the following technical solutions: A method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting includes the following steps: Construct monitoring boreholes independent of the grouting holes at the interface of the thin bedrock layer, and install sealing devices at the borehole openings of the monitoring boreholes. The water pressure test is initiated. When the pressure inside the borehole reaches the preset target threshold for pressure stabilization, the water pressure test is stopped and a pressure recovery period begins. During the pressure recovery period, a sliding time window is used to identify the pressure steady state, and the average pressure value under the steady state is calculated as the initial pressure reference value. ; During the grouting operation, transient pressure measurements inside the borehole are collected and monitored in real time. ,according to Compared with the initial pressure reference value Calculate the pressure amplitude characteristics and pressure change rate characteristics; When the pressure amplitude feature and pressure change rate feature meet the preset Boolean variable combination conditions, the corresponding counter is incremented by 1, and the graded warning status word is output based on the comparison result between the cumulative value of the counter and the preset graded warning frame number threshold. The control system receives the graded early warning status word and drives the frequency converter of the grouting pump in the grouting system to perform closed-loop pressure reduction operation, or drives the grouting system to perform emergency shutdown and pipeline depressurization operation.

[0007] Furthermore, the final depth of the monitored borehole Calculate using the following formula: In the formula, To monitor the surface elevation at the borehole opening; After obtaining the three-dimensional seismic impedance data of the target working face, the interface elevation of the thin bedrock segment is determined by fitting the continuous surface where the impedance gradient change rate exceeds the preset abrupt change threshold. This is the preset layer penetration safety redundancy.

[0008] Furthermore, the sealing device is a mechanically anchored bidirectional polyurethane bag sealer installed in the stable rock strata at the borehole opening. A high-pressure pressure-inducing steel pipe extending to the bottom of the borehole is pre-reserved in the center of the sealer, and the surface end of the high-pressure pressure-inducing steel pipe is connected to a pressure sensor through a pressure-inducing flange.

[0009] Furthermore, the process for identifying the pressure steady state involves calculating the length of the pressure recovery period. The pressure fluctuation range within the sliding time window is extremely small. ;when continuous When all sampling periods are less than the preset minimum threshold for stable judgment, the judgment pressure enters a stable state.

[0010] Furthermore, the pressure amplitude characteristic and pressure change rate characteristic are determined by the following Boolean variables: Amplitude Boolean variable :when hour, Otherwise ,in This is the preset amplitude safety factor; slope Boolean variable :when hour, Otherwise ,in To preset the step size, This is a preset critical pressure mutation rate threshold.

[0011] Furthermore, the logic for incrementing the counter by 1 includes: like and All Then execute the secondary alarm counter. The value is incremented by 1, and the first-level alarm counter is executed. Reset to zero; like for and Then execute the first-level alarm counter. Increment the value by 1 and execute. Reset to zero; like for If it is determined that there is no risk of slurry overflow or that it is an environmental disturbance, then... and Forced reset to zero.

[0012] Furthermore, when When the preset threshold for the first-level early warning frame count is reached, the control system obtains the real-time feedback pressure on the main pipeline of the grouting system. And calculate the target safety pressure The frequency increment of the grouting pump inverter is adjusted by an incremental PID algorithm.

[0013] Furthermore, when When the preset threshold for the number of secondary warning frames is reached, the control system drives the intermediate relay to cut off the power supply to the contactor coil of the grouting pump main motor and drives the normally closed electromagnetic pressure relief valve on the grouting system pipeline to open.

[0014] A system for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting, comprising the following steps: The monitoring borehole module is constructed at the interface of a thin bedrock layer. Its borehole opening is equipped with a sealing device and a pressure sensor to create an independent in-situ sealed test space. The early warning algorithm module is used to establish an initial pressure reference value during the pressure recovery period after the pressure test is stopped. Based on real-time pressure measurements and The Boolean combination of the amplitude and rate of change between them outputs a graded warning status word; An automated control module, connected to the grouting system, is used to receive the graded early warning status words and adjust the output frequency of the grouting pump frequency converter accordingly, or control the operation status of the grouting pump main motor contactor and electromagnetic pressure relief valve.

[0015] Furthermore, the automation control module communicates with the host computer where the early warning algorithm module is located via the ModbusTCP protocol. The PLC controller in the automation control module is connected to the analog pins of the grouting pump frequency converter and the digital pins of the main motor contactor.

[0016] The beneficial effects of this invention are: 1. This invention constructs a monitoring borehole at the interface of a thin bedrock layer, independent of the grouting hole, and installs a sealing device and a high-frequency pressure sensor in the stable bedrock layer at the borehole opening; in physical space, it constructs an in-situ sealed test space that is not directly disturbed by external atmospheric pressure and high-pressure grouting pulses; when external grout enters this space, its volume change can be sensitively converted into pressure fluctuations.

[0017] 2. This invention introduces an automated water pressure test before formal grouting and uses a sliding time window algorithm to calculate continuous steady-state data to generate a dynamic initial pressure benchmark value for a specific borehole location. Due to significant differences in natural groundwater head height and initial stress of rock strata in different mines and even different geological areas of the same working face, the system can obtain the true hydrostatic pressure background of the target stratum without grout interference, transforming the traditional "fixed absolute threshold judgment" into "relative pressure difference judgment," which effectively reduces the systematic error caused by differences in geological environment and improves the applicability of the early warning system under different working conditions.

[0018] 3. This invention employs dual characteristic parameters, including pressure amplitude exceedance and pressure change rate (slope) abrupt change, combined with a continuous time window counter based on state machine logic for online identification and judgment. When high-pressure slurry enters the sealed monitoring hole at the interface, it causes an increase in the fluid extrusion rate. This algorithm mechanism can not only capture such pressure anomalies but also filter out instantaneous high-frequency electromagnetic or mechanical disturbance signals caused by the start-up and shutdown of large electromechanical equipment through the integral clearing mechanism of the time window counter.

[0019] 4. Based on the early warning status word output by the algorithm, the present invention directly drives the grouting station to perform graded actions through communication between the host computer and the PLC bus: the first-level early warning triggers the inverter PID closed-loop voltage reduction, and the second-level early warning triggers the main contactor to cut off power and the electromagnetic pressure relief valve to open. This opens up the data link from the upper-level software digital early warning to the lower-level industrial high-power equipment physical control, enabling the grouting system to autonomously adjust operating parameters or perform emergency shutdown according to the risk level. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of the method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to the present invention; Figure 2 This is a schematic diagram of the monitoring borehole. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1 This invention proposes a method for early warning, monitoring, and handling of grout leakage risks in thin bedrock delamination grouting. By setting up monitoring boreholes at the bedrock interface, the method monitors in real time whether grout is leaking into the interface, and uses borehole pressure changes for early warning and automatic handling. Figure 1 As shown, the method includes the following steps: Step 1: Conduct monitoring boreholes at the interface of the thin bedrock layer and install sealing devices at the borehole openings; Step 1.1: Interface spatial elevation extraction and borehole parameter calculation based on geological data; A schematic diagram of the borehole monitoring is shown below. Figure 2 As shown, a three-dimensional seismic impedance data array of the target working face was obtained, and threshold values ​​for impedance abrupt changes between the thin bedrock and the overlying aquifer / loose layer were set. The algorithm traverses the wave impedance data array and extracts data when the wave impedance gradient change rate exceeds a set abrupt change threshold. The continuous surface is fitted and calibrated as the interface of the thin bedrock segment.

[0024] Obtain the surface elevation of the designed borehole location for the monitoring well. Calculate the elevation of the interface of the thin bedrock section corresponding to this coordinate point. Then, the final drilling depth of the monitored borehole is calculated at the system's underlying level. The calculation formula is: in, Indicates the final drilling depth (in meters) of the borehole being monitored. This indicates the absolute coordinates of the ground surface elevation at the borehole opening of the monitoring borehole (unit: m) entered by the system. This represents the absolute elevation (in meters) of the thin bedrock segment interface at the target coordinates, obtained by fitting the wave impedance abrupt change threshold. This represents the set layer penetration safety redundancy (unit: m). In this embodiment, it is set as follows: .

[0025] Step 1.2: Directional construction and physical isolation; Based on calculations Perform drilling operations to ensure that the bottom of the borehole precisely penetrates to at least below the interface of the thin bedrock section. At the position, an in-situ test space for constructing a connected potential grout leakage fissure channel is built. This monitoring hole is independent of the grouting hole array in three-dimensional space and is not physically connected to the high-pressure grouting pipeline.

[0026] Step 1.3: High-pressure resistant sealing at the hole mouth and reservation of the pressure guiding channel; Within the stable bedrock section from the drilling hole mouth to below the ground surface (in this embodiment, take ), install a mechanical anchoring type two-way polyurethane bladder hole plugging device. A high-pressure pressure guiding steel pipe that penetrates through to the hole bottom is reserved at the center of the hole plugging device, and a pressure guiding flange is connected to the ground end face. Set the rated hydrostatic pressure threshold of this sealing component to ensure the formation of a sealed pressure measuring cavity that is completely not interfered by the atmospheric pressure on the ground surface.

[0027] Step 1.4: System registration of the monitoring point After the physical construction is completed, the unique identifier (ID), three-dimensional space coordinates , interface elevation of this monitoring borehole, as well as the elevation information of the pressure guiding flange, are entered into the database of the ground online monitoring system as initialization parameters to complete the system instantiation registration of the physical monitoring point, serving as the input object for subsequent calculation of the pressure reference value and mutation warning algorithm.

[0028] Through the wave impedance gradient change rate algorithm, the computer can automatically and quantitatively determine the elevation of the weakest interface where grout leakage is most likely to occur; through the formula it ensures that the physical drill bit accurately covers the potential grout leakage channels. At the same time, the instantiation registration in Step 1.4打通了从实体岩层物理节点到软硬件预警系统数字节点的数据通道,为后续步骤中计算相对压差和执行自动化联动干预提供了准确的空间坐标和对象指向基准。

[0029] Step 2: Install a pressure sensor at the hole mouth of the monitoring borehole and connect it to the online monitoring system to collect the pressure data in the hole in real time; Step 2.1: Physical signal perception and high-precision analog-to-digital (A / D) conversion At the reserved pressure guiding hole of the flange described in Step 1, install an intrinsically safe piezoresistive high-precision pressure sensor by threaded direct connection; a microporous anti-blocking filter is set at the front end of the sensor; the Wheatstone bridge inside the sensor converts the physical extrusion pressure in the sealed pressure measuring cavity into an analog voltage signal.

[0030] The built-in A / D conversion module of the sensor samples the analog signal discretely at the set hardware sampling frequency and converts the analog voltage into digital pressure amplitude data with a resolution of at least 16 bits (16-bit).

[0031] Step 2.2: Data frame encapsulation and network transmission based on device registration ID.

[0032] The system obtains the unique identifier (ID) of the monitoring borehole instantiated by the system in step 1.4; the microprocessor built into the sensor concatenates the current digital pressure amplitude data, the current system absolute timestamp, and the borehole ID in each sampling cycle to generate a standard data frame.

[0033] The data structure of a data frame is defined as: Header + Drill ID + Timestamp + Pressure Digital Value + CRC Check Code; The encapsulated data frame is sent to the downhole data substation via RS485 bus, and then transmitted to the data parsing gateway of the ground host computer control system via the mining industrial Ethernet ring network.

[0034] Step 2.3: Data unpacking and time series sequence construction; After receiving the data frame, the ground-based host computer gateway verifies the CRC and unpacks it. Using the "borehole ID" in the data frame as the primary key, it routes the data and stores the extracted pressure values ​​in the memory queue corresponding to the borehole in timestamp order. This constructs an evenly spaced discrete time series within the system for direct use by the early warning algorithm. .

[0035] Among them, time series The generation logic conforms to the following mathematical relationship: In the formula, Indicates the first The time nodes corresponding to each sampled data point (unit: seconds); This indicates the initial zero-point timestamp at which the system begins executing monitoring and recording. The sequence index number of the sampled data point is a positive integer ( ); This represents the time interval (i.e., sampling period, unit: s) between two adjacent sampled data points. This indicates the hardware sampling frequency of the sensor's A / D conversion (preferred in this embodiment). ). Indicates at a time node Recorded transient pressure digital measurements (unit: MPa) that are associated with a specific borehole ID.

[0036] Step 3: Conduct a water pressure test before grouting to establish an initial pressure reference value; monitor the pressure change at the orifice in real time during grouting. Step 3.1: Automated water pressure test and pressure stabilization trigger; Before the formal delamination grouting operation, the ground-based supervisory control system issues a start command to the water pump station. The system monitors the sequence generated in step 2 in real time. When the real-time pressure inside the orifice Reaching the set voltage regulation target threshold Time (in this embodiment) ,in (Based on the pre-imported closed pressure constant of the formation), the host computer control system sends a closing command to the solenoid valve of the pressurized water pipeline, and the system enters the "static pressure recovery period".

[0037] Step 3.2: Automatic identification algorithm for "stress steady state" based on sliding window; After the solenoid valve closes, the host computer algorithm module starts a process of length [length missing]. (represents inclusion) A dynamic sliding time window (number of sampling points) that adjusts with the latest sampling time. Slide forward synchronously.

[0038] In each sampling period, the algorithm calculates the pressure fluctuation range within the current sliding window. .when continuous Each sampling period is less than the set minimum threshold for stability determination. When the algorithm determines that the fluid pressure inside the orifice has entered a true physical steady state, it locks the current time window and triggers the baseline value calculation module.

[0039] The logic for identifying stationary states is as follows: The determination condition is: when there is a current time... This makes it possible for all All satisfy .

[0040] in, This indicates that the current length is Within the sliding window, the range between the maximum and minimum pressure values ​​(unit: MPa). This represents the system's set minimum threshold for stability determination (unit: MPa, preferred range is...). ); This represents a constant number of consecutive verifications set to prevent accidental fulfillment of the condition (e.g., ...). ); This indicates that in the sequence generated in step 2, the first... Transient pressure digital measurement value at each moment (unit: MPa); This indicates the length of the sliding time window set by the algorithm (i.e., the number of sampling points included, such as setting the window time to 5 minutes and...). ,but ).

[0041] Step 3.3: Baseline value calculation and ID binding persistence; Discrete pressure data within a locked steady-state time window are extracted, and their arithmetic mean is calculated as the initial pressure reference value for the borehole. After the calculation is complete, A one-to-one mapping relationship is established with the "drill ID" parsed in step 2, and written into the system's real-time database as a static reference surface for the anomaly identification algorithm in the subsequent step 4.

[0042] The formula for calculating the benchmark value is: in, This represents the final output dynamic initial pressure reference value (unit: MPa) that is bound to the corresponding borehole ID.

[0043] Step 4: Determine whether the orifice pressure is abnormal based on the initial pressure benchmark value. When abnormal orifice pressure is detected, the system automatically determines that grout has entered the bedrock interface and triggers an early warning signal. Specifically, it includes: Step 4.1: Data cache initialization and out-of-bounds check; After the formal grouting begins, the ground-based host computer system receives the real-time pressure sequence generated in step 2. and press it into a length of The system uses a first-in, first-out (FIFO) computational buffer queue. First, it performs an out-of-bounds check: determining the total number of valid sample points currently pushed into the buffer. Is it greater than the parameter? .like The algorithm then waits and outputs the state. ;like Then the feature extraction module will be activated.

[0044] Step 4.2: Real-time calculation and Boolean determination of discrete feature parameters; For each time that the condition is met The system retrieves the current value from the cache queue. and lag value And call the baseline value generated in step 3. Calculate the magnitude and slope characteristics respectively, and output two Boolean state variables. and : Amplitude Boolean variable :when hour, ;otherwise .

[0045] slope Boolean variable :when hour, ;otherwise .

[0046] Step 4.3: Jitter-resistant counter logic based on finite state machine (FSM); The system initializes two integer counters in memory: a level 1 alarm counter. Level 2 alarm counter Based on the Boolean combination output from step 4.2, execute the following strict exhaustive branching logic: Branch 1 (violent slurry flow): If Then the accumulation will be performed. and force reset to zero. .

[0047] Branch 2 (slow seepage): If Then the accumulation will be performed. and force reset to zero. .

[0048] Branch 3 (Perturbation or Normal): If ,regardless Regardless of the status, it is determined to be either a pressure drop or normal, and a forced reset is performed. and .

[0049] Step 4.4: Triggering and outputting the alert status word; The accumulated counter value is compared with the number of frames tolerated within the system's set time window. Compare: when At that time, output the current warning status word. ; like but At that time, output the current warning status word. ; In all other cases, output .

[0050] This status word It is packaged into the control bus and serves as the sole instruction trigger source for the automatic control module in step 5.

[0051] The formula for calculating the counting trigger threshold is: in, Indicates the current Real-time pressure measurement at any given moment (unit: MPa); This represents the initial pressure reference value (unit: MPa) calculated and bound in step 3. This represents the step size span for calculating the slope of pressure change (e.g., taking...). (This represents a comparison of data from 5 sampling periods ago). Indicates the sampling period (in this embodiment) ); This represents the amplitude safety factor (a constant, with a value of...). ); Indicates the critical pressure mutation rate threshold (unit: MPa / s); The tolerance time windows (in seconds) set for Level 1 warning (slow seepage) and Level 2 warning (violent crossflow) are respectively. ); This indicates that the time window is converted into a threshold for the number of judgment frames (dimensionless integer) in the discrete time domain of the system. This represents an integer state accumulator variable allocated in system memory; Indicates in The control state word output by the timing algorithm has a value space of 1. .

[0052] Step 5: The early warning signal triggers the grouting system to automatically reduce the grouting pressure and suspend grouting, while simultaneously notifying on-site personnel through the online system.

[0053] Specifically, it includes: Step 5.1: Control instruction parsing and hardware interface mapping; The ground-based host computer system reads the warning status word output in step 4 during each control cycle. The status word is sent to the PLC control cabinet of the grouting station via the Modbus TCP protocol. Based on the parsed status value, the PLC drives its internal execution logic program and maps the control variables to physical output terminals: including the analog output pins (AO, such as 4-20mA signals) controlling the grouting pump frequency converter and the digital output pins (DO) controlling the solenoid valves and main contactors.

[0054] Step 5.2: When Time (closed-loop depressurization and time-series flow of Level 1 early warning); When a Level 1 warning status transition is detected, the system initializes a buck observation timer. And activate the pipeline pressure closed-loop control (PID) module.

[0055] The algorithm first calculates the target safety pressure. The PLC collects real-time feedback pressure on the current grouting main pipeline. The incremental control signal of the output frequency converter is calculated in real time using a discrete incremental PID algorithm. This dynamically reduces the operating frequency of the grouting pump motor until the pipeline pressure stabilizes at a certain level. nearby.

[0056] Formula for calculating target blood pressure reduction: in, Indicates the set safety pipeline pressure for the Level 1 early warning target (unit: MPa); : Real-time grouting pressure on the main grouting pipeline at the moment the Level 1 warning is triggered (Note: This is not the monitoring hole pressure, but the grouting pipeline pressure, unit: MPa). For system identification and output The system timestamp at the moment of the state transition; This represents the voltage drop factor set by the system (the range of values ​​in this embodiment is...). ).

[0057] Formula for discrete incremental PID control of frequency converter: in, Indicates the first Pressure deviation value for each control cycle; Indicates that the PLC is in the... The increment of the control voltage / current signal output to the inverter per control cycle (used for fine-tuning the inverter frequency). This is the execution sequence number index for the PLC control loop; These represent the proportional, integral, and derivative control gain coefficients, respectively.

[0058] Timing transition mechanism: In During the timing period (set to 300 seconds in this example): If the status word is upgraded to If this happens, immediately interrupt this step and proceed to step 5.3; If the timer ends and If the value returns to 0, it is determined that the intermittent cross-current has been recompacted, the system triggers the recovery program, and the frequency converter frequency slowly rises back to the initial grouting parameters according to the set slope.

[0059] Step 5.3: When Time (hard intervention and information push of Level II early warning).

[0060] Upon receiving a Level 2 warning command, the PLC immediately executes the highest-priority emergency blocking sequence: Physical interruption: Setting a specific DO pin of the PLC to a high level triggers an intermediate relay, instantly cutting off the power supply to the control coil of the grouting pump main motor contactor (KM), thus achieving a hard-wired forced shutdown. High pressure relief: Simultaneously set another DO pin to drive the normally closed electromagnetic pressure relief valve on the grouting pipeline to open, and release the high pressure of the pipeline to the return grout pool within 2 seconds, completely destroying the hydrodynamic conditions for the movement of grout in the cracks.

[0061] Data bus push: The host computer system extracts the "borehole ID" that triggered the alarm as the primary key, retrieves the "3D spatial coordinates" and "surface elevation at the borehole opening" of the borehole from the system instance library established in step 1.4, and extracts the "transient pressure value" at the current moment. The system concatenates these three data items into a JSON-formatted alarm message and pushes it to the designated personnel's mobile terminal via the mine area SMS gateway interface (API).

[0062] Example 2 In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A thin-bed rock separation grouting slurry spouting risk early warning monitoring and processing method, characterized in that, Includes the following steps: Construct monitoring boreholes independent of the grouting holes at the interface of the thin bedrock layer, and install sealing devices at the borehole openings of the monitoring boreholes. Starting the water pressure test, stopping the water pressure when the pressure in the borehole reaches a preset steady pressure target threshold, and entering a pressure recovery period, identifying a pressure steady state in the pressure recovery period by using a sliding time window, and calculating a pressure average value in the steady state as an initial pressure reference value ; During the grouting operation, transient pressure measurements inside the borehole are collected and monitored in real time. ,according to Compared with the initial pressure reference value Calculate the pressure amplitude characteristics and pressure change rate characteristics; When the pressure amplitude feature and pressure change rate feature meet the preset Boolean variable combination conditions, the corresponding counter is incremented by 1, and the graded warning status word is output based on the comparison result between the cumulative value of the counter and the preset graded warning frame number threshold. The control system receives the graded early warning status word and drives the frequency converter of the grouting pump in the grouting system to perform closed-loop pressure reduction operation, or drives the grouting system to perform emergency shutdown and pipeline depressurization operation.

2. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 1, characterized in that, The final depth of the monitored borehole Calculate using the following formula: In the formula, To monitor the surface elevation at the borehole opening; After obtaining the three-dimensional seismic impedance data of the target working face, the interface elevation of the thin bedrock segment is determined by fitting the continuous surface where the impedance gradient change rate exceeds the preset abrupt change threshold. This is the preset layer penetration safety redundancy.

3. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 1, characterized in that, The sealing device is a mechanically anchored bidirectional polyurethane bag sealer installed in the stable rock strata at the borehole opening. A high-pressure pressure-inducing steel pipe extending to the bottom of the borehole is pre-reserved in the center of the sealer. The surface end of the high-pressure pressure-inducing steel pipe is connected to a pressure sensor through a pressure-inducing flange.

4. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 1, characterized in that, The process for identifying the pressure steady state is as follows: Calculate the length of the pressure recovery period. The pressure fluctuation range within the sliding time window is extremely small. ;when continuous When all sampling periods are less than the preset minimum threshold for stable judgment, the judgment pressure enters a stable state.

5. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 1, characterized in that, The pressure amplitude characteristics and pressure change rate characteristics are determined by the following Boolean variables: Amplitude Boolean variable :when hour, Otherwise ,in This is the preset amplitude safety factor; slope Boolean variable :when hour, Otherwise ,in To preset the step size, This is a preset critical pressure mutation rate threshold.

6. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 5, characterized in that, The logic for incrementing the counter by 1 includes: like and All Then execute the secondary alarm counter. The value is incremented by 1, and the first-level alarm counter is executed. Reset to zero; like for and Then execute the first-level alarm counter. Increment the value by 1 and execute. Reset to zero; like for If it is determined that there is no risk of slurry overflow or that it is an environmental disturbance, then... and Forced reset to zero.

7. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 6, characterized in that, when When the preset threshold for the first-level early warning frame count is reached, the control system obtains the real-time feedback pressure on the main pipeline of the grouting system. And calculate the target safety pressure The frequency increment of the grouting pump inverter is adjusted by an incremental PID algorithm.

8. The method for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting according to claim 6, characterized in that, when When the preset threshold for the number of secondary warning frames is reached, the control system drives the intermediate relay to cut off the power supply to the contactor coil of the grouting pump main motor and drives the normally closed electromagnetic pressure relief valve on the grouting system pipeline to open.

9. A system for early warning monitoring and handling of grout leakage risk in thin bedrock delamination grouting, comprising the method described in any one of claims 1-8, characterized in that, include: The monitoring borehole module is constructed at the interface of a thin bedrock layer. Its borehole opening is equipped with a sealing device and a pressure sensor to create an independent in-situ sealed test space. The early warning algorithm module is used to establish an initial pressure reference value during the pressure recovery period after the pressure test is stopped. Based on real-time pressure measurements and The Boolean combination of the amplitude and rate of change between them outputs a graded warning status word; An automated control module, connected to the grouting system, is used to receive the graded early warning status words and adjust the output frequency of the grouting pump frequency converter accordingly, or control the operation status of the grouting pump main motor contactor and electromagnetic pressure relief valve.

10. The thin bedrock delamination grouting grout leakage risk early warning monitoring and handling system according to claim 9, characterized in that, The automation control module communicates with the host computer where the early warning algorithm module is located via the Modbus TCP protocol. The PLC controller in the automation control module is connected to the analog pins of the grouting pump frequency converter and the digital pins of the main motor contactor.

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