Dynamic self-adaption and multi-physics field coupled coal roadway impact test system and method

Abstract

The invention discloses a dynamic self-adaption and multi-physics field coupled coal roadway impact test system and method, and belongs to the technical field of coal roadway tunneling. The system comprises a coal roadway tunneling model, loading equipment, a sensor module, a multi-strain-rate coupling feedback module, a control module and numerical simulation software. Loading equipment comprises an impact oil cylinder, a thrust oil cylinder and a variable-stiffness spring, and the position of an impact module can be adjusted. The sensor module collects a variety of data. The multi-strain-rate coupling feedback module processes sensor signals. The control module controls all the parts to operate. The impact method comprises the steps of system initialization, data acquisition and processing, state evaluation and instruction generation, loading parameter adjustment and analog calculation, result feedback and optimization and the like. The method can monitor and adjust in real time, considers multi-physical field coupling, accurately evaluates the stability of the coal roadway, improves the tunneling safety and efficiency, and can be widely applied to the field of coal roadway tunneling engineering.

Description

Technical Field

[0001] The present invention relates to the technical field of coal roadway tunneling, and particularly relates to a coal roadway impact test system and method with dynamic adaptability and multi-physical field coupling. Background Art

[0002] During the process of coal roadway tunneling, complex geological conditions and engineering environments are faced, such as changes in the mechanical properties of rocks, interactions between multi-physical fields (stress field, temperature field, seepage field, etc.). Traditional tunneling methods and equipment are difficult to accurately simulate and cope with these complex situations, resulting in low tunneling efficiency and increased safety risks. Therefore, a coal roadway tunneling impact system and method that can dynamically adaptively adjust and consider the coupling effect of multi-physical fields are needed to improve the safety and efficiency of the tunneling process. Summary of the Invention

[0003] The purpose of the present invention is to provide a coal roadway impact test system and method with dynamic adaptability and multi-physical field coupling, so as to achieve precise control and simulation of the coal roadway tunneling process and improve tunneling efficiency and safety.

[0004] To achieve the above purpose, the present invention provides a coal roadway impact test system with dynamic adaptability and multi-physical field coupling, including a coal roadway tunneling model, which is respectively connected to a loading device and a sensor module. The sensor module is connected to a multi-strain rate coupling feedback module, and the multi-strain rate coupling feedback module is connected to a control module. The control module is also connected to numerical simulation software and the loading device. The loading device includes an impact module, a propulsion oil cylinder, and a variable stiffness spring. The impact module is located above the coal roadway tunneling model, and propulsion oil cylinders and variable stiffness springs are arranged on the front, rear, left, right, and upper five outer surfaces of the coal roadway tunneling model. The spring material adopts a new type of high-performance alloy spring steel, which has excellent elastic recovery performance and anti-fatigue characteristics. The combination of internal multi-layer spring sheets or spring wires with different elastic moduli is optimized in design, and its stiffness change curve is highly consistent with the stiffness change of the actual coal roadway surrounding rock.

[0005] Preferably, the sensor module includes a stress sensor, a strain sensor, a deformation rate sensor, a pressure sensor, a temperature sensor, and a seepage sensor. The pressure sensor is installed inside the propulsion oil cylinder and the coal roadway tunneling model, and the stress sensor, the strain sensor, the deformation rate sensor, the temperature sensor, and the seepage sensor are all installed inside the coal roadway tunneling model.

[0006] Preferably, the multi-strain rate coupling feedback model includes a data acquisition card, a signal conditioning circuit, and a microprocessor;

[0007] The data acquisition card is used to receive the analog signals from each sensor and convert them into digital signals;

[0008] The signal conditioning circuit is used to preprocess the signals output by the sensors;

[0009] The microprocessor is used to control the data acquisition process and perform preliminary processing and analysis on the acquired data.

[0010] Preferably, the control module includes a communication module, a control computer, a data storage device, and control algorithm software;

[0011] The communication module is used to communicate and transmit with the multi-strain rate coupling feedback module and the numerical simulation software;

[0012] The control computer is used to run the control algorithm and data processing software and receive data from the multi-strain rate coupling feedback module;

[0013] The data storage device is used to store the acquired data, system operation parameters, and information of the control algorithm;

[0014] The control algorithm software is used to run the algorithm program.

[0015] Preferably, the impact module includes a mounting plate, an electromagnetic shaker, and an adjustment bracket. A sliding track is provided at the bottom of the mounting plate. The adjustment bracket is mounted on the sliding track and connected to the electromagnetic shaker. The adjustment bracket includes a position movement bracket, an angle adjustment bracket, and an adjustment mounting block connected in sequence. The electromagnetic shaker is connected to the adjustment mounting block through a rotating shaft.

[0016] A coal roadway impact test method with dynamic adaptability and multi-physical field coupling includes the following steps:

[0017] S1. System initialization: Set the initial parameters of the electromagnetic shaker and the oil cylinder propulsion device, calibrate each sensor, start the multi-strain rate coupling feedback module, the intelligent control module, and the numerical simulation software, and establish communication connections between the modules;

[0018] S2. Data acquisition and preliminary processing: The multi-strain rate coupling feedback module collects the data of each sensor according to the preset sampling frequency, performs signal conditioning, analog-to-digital conversion, data verification, and preliminary analysis processing on the data to obtain the real-time data of each sensor and the corresponding change rates, and transmits the acquired data to the intelligent control module in real time for storage and processing;

[0019] S3. System state evaluation and control instruction generation: The intelligent control module receives the data processed by the multi-strain rate coupling feedback module, calculates the stiffness K value and its change rate of the system according to the built-in algorithm, and compares and analyzes the current system state with the preset target state (including the K range, temperature field range, seepage field range, etc. at different stages). Generate control instructions according to the control algorithm, such as adjusting the static load pressure of the propulsion oil cylinder, triggering the electromagnetic shaker to apply dynamic load, adjusting the position and angle of the electromagnetic shaker, etc.;

[0020] S4. Loading parameter adjustment and simulation calculation. The intelligent control module sends control instructions to the corresponding loading devices, and the loading devices adjust the loading parameters according to the instructions. The propulsion cylinder adjusts the static load pressure, and the electromagnetic vibrator applies the dynamic load at the appropriate time. Meanwhile, the intelligent control module transmits the data to the numerical simulation software, and the numerical simulation software performs multi-physical field coupling calculations, simulates the physical field changes, and evaluates the stability of the coal roadway.

[0021] S5. Result feedback and optimization. The intelligent control module compares and evaluates the simulation results with the actual monitoring data (the actual deformation measured by the displacement sensor and the actual stress measured by the stress sensor). Calculate the mean absolute error MAE and the root mean square error RMSE. If the error is large, analyze the model parameter error, the physical field coupling relationship error, and the sensor measurement error, adjust the relevant parameters, and then recalculate and optimize to continuously improve the system control accuracy and stability.

[0022] Preferably, in step S2, after the system starts, the data acquisition system collects the mechanical response data and the physical field parameter data according to the preset acquisition frequency, and transmits the collected data to the intelligent control module in real time for storage and processing.

[0023] Preferably, in step S3, the steps of calculating the stiffness K and its change rate are as follows:

[0024] Calculating the stiffness K:

[0025] Calculate the stiffness K according to the formula K = F / ΔL. During the calculation process, the loading force F measured by the pressure sensor and the deformation amount ΔL measured by the strain sensor are monitored in real time;

[0026] If abnormal data is detected, start the data verification and correction program; data verification uses the parity check method to append a parity bit during data transmission (in odd parity, make the number of "1"s in the data bits and the parity bit odd; in even parity, make the number of "1"s even), and the receiving end judges whether the data is correct according to the verification rules;

[0027] If the data is incorrect, correct it using the corresponding error correction algorithm according to the error type (such as single-bit error, multi-bit error, etc.). The present invention uses the Hamming code error correction algorithm.

[0028] Calculating the change rate of the stiffness K

[0029] Use the sliding window method to calculate the change rate of the stiffness K The calculation formula is as follows:

[0030]

[0031] Among them, K(t) is the stiffness at the current moment, K(t - Δt) is the stiffness at the previous moment, and Δt is the time interval;

[0032] The size of the sliding window is set according to the requirements of the system response speed and data stability. During the calculation process, the K values at each time point are stored and updated to ensure the accuracy of the calculation.

[0033] Preferably, in step S3, judging the stage where the coal roadway is located includes judging the elastic change stage and the plastic deformation stage, which are specifically as follows:

[0034] Judgment of the elastic change stage

[0035] Set the elastic modulus range to [E min , E max . When the calculated stiffness K satisfies K ≈ constant, the constant judgment adopts the relative error method:

[0036]

[0037] Among them, K prev is the stiffness at the previous moment, κ is the set relative error threshold, and when E min <K<E max , it is judged that the coal roadway is in the elastic deformation stage;

[0038] Judgment of the plastic deformation stage

[0039] When the stiffness K starts to decrease, K(t) < K(t - Δt) and lasts for a certain period of time, and the deformation rate gradually increases, where the deformation rate

[0040] is calculated by calculating the change rate of the deformation rate

[0041] When and lasts for a certain period of time, it indicates that the coal roadway enters the plastic deformation stage;

[0042] When in the elastic deformation stage - the stress is less than the safety stress threshold:

[0043] Preset the safety stress threshold σ safe , and the calculation formula is as follows:

[0044] σ safe =kξ safe ;

[0045] Among them, k is the elastic modulus, and ξ safe is the safety strain threshold; when the stress σ = Kξ < Kξ safe , increase the static load pressure at the preset loading rate , and its expression is

[0046]

[0047] Among them, r is the loading rate coefficient, and P is the current static load pressure. (r is determined according to the requirements of the coal roadway driving speed and the characteristics of coal and rock)

[0048] When in the elastic deformation stage - when the stress approaches the safety stress threshold:

[0049] When the stress σ satisfies σ safe -δ < σ < σ safe +δ, keep the static load pressure unchanged and appropriately increase the dynamic load frequency;

[0050] Among them, δ is the judgment range close to the threshold; (the increase amount Δf of the dynamic load frequency is determined according to the stability analysis of the coal roadway and experimental experience)

[0051] Plastic deformation stage:

[0052] When it is judged that the coal roadway enters the plastic deformation stage, reduce the dynamic load frequency;

[0053] The dynamic load frequency reduction coefficient c is determined according to the plastic deformation characteristics of coal and rock. The new dynamic load frequency is as follows:

[0054] f new = f prev (1 - c);

[0055] Among them, f prev is the previous dynamic load frequency, and at the same time reduce the dynamic load magnitude. The calculation formula for the dynamic load magnitude is:

[0056]

[0057] Among them, d is the coefficient for adjusting the dynamic load magnitude according to the deformation rate, is the deformation rate.

[0058] Input the temperature field data T(x, y, z, t) collected by the temperature sensor, the seepage velocity v(x, y, z, t) collected by the seepage sensor, and the seepage pressure p s (x, y, z, t) into the numerical simulation software, where x, y, z are the spatial coordinates in the model, and t is the time;

[0059] Construct a multi - physical - field coupling model, considering the actual geometric shape and size of the coal roadway and the physical and mechanical properties of the surrounding rock;

[0060] Set the initial conditions of the temperature field and the seepage field, the initial temperature distribution T0(x, y, z), the initial seepage velocity v0(x, y, z), and the seepage pressure p s0 (x, y, z); the boundary condition is that the temperature at the model boundary is constant T b, the seepage velocity v is zero b = 0;

[0061] The numerical simulation software uses numerical calculation methods such as the finite element method or the finite difference method to perform multi - physical - field coupling calculations;

[0062] When calculating the stress field, consider the thermal stress σ caused by the temperature field T = Eα T ΔT and the seepage body force generated by the seepage field where, ΔT = T - T0 is the temperature change amount, is the seepage pressure gradient, is the gradient operator;

[0063] The stress equilibrium equation is

[0064] where, θ is the total stress tensor, ρ is the density, and a is the body force;

[0065] Analyze the stability of the coal roadway under the coupling action of multi - physical fields:

[0066] First, calculate the safety factor

[0067] where, θ c is the uniaxial compressive strength of coal and rock, and θ max is the calculated maximum principal stress; when FOS < 1, it indicates that the coal roadway is in an unstable state. At this time, the intelligent control module will take corresponding emergency control measures, such as immediately stopping the loading, sending out an alarm, etc.

[0068] Preferably, in step S5, compare and evaluate the deformation situation δ sim (x, y, z) and stress distribution δ sim (x, y, z) of the coal roadway calculated by the numerical simulation software with the actual deformation δ real (x, y, z) measured by the displacement sensor and the actual stress δ real (x, y, z) measured by the stress sensor, and the specific steps are as follows:

[0069] Calculate the mean absolute error MAE:

[0070] The mean absolute error of deformation,

[0071] The mean absolute error of stress,

[0072] where, n is the number of monitoring points;

[0073] Calculate the root mean square error RMSE:

[0074] The root mean square error of deformation,

[0075] Root mean square error of stress

[0076] If the MAE and RMSE are large, it indicates that there is a large deviation between the simulation results and the actual situation. At this time, analyze the model parameter error, the physical field coupling relationship error, and the sensor measurement error;

[0077] Finally, feedback the evaluation results to the control system and the simulation calculation module.

[0078] Therefore, the dynamic adaptive and multi - physical - field - coupled coal roadway impact test system and method with the above structure of the present invention have the following beneficial effects:

[0079] (1) The present invention collects a variety of data in real - time through the sensor module, and the multi - strain - rate coupling feedback module and the control module work together to achieve dynamic adaptive control of the loading equipment. At the same time, considering the multi - physical - field coupling effect, precise calculation and analysis are carried out through numerical simulation software, which can more accurately evaluate the stability during the coal roadway driving process, improve the safety and efficiency of driving, and reduce the occurrence of engineering accidents.

[0080] (2) Through the coordinated work of the multi - strain - rate coupling feedback module and the control module, the present invention monitors the mechanical response data of the coal roadway driving model during the impact process in real - time. According to the accurate judgment of the rock deformation stage, the intelligent control module can accurately adjust the parameters of the loading equipment, making the loading process highly match the actual mechanical properties of the coal and rock, avoiding over - loading or under - loading, thereby effectively improving the driving efficiency and reducing unnecessary energy consumption and equipment wear.

[0081] (3) During the driving process, the present invention continuously collects and analyzes data, and continuously optimizes the driving parameters according to the real - time state of the coal and rock. Compared with the traditional driving method with fixed parameters, the present invention can better adapt to the complex and changeable geological conditions of the coal roadway, greatly shorten the driving cycle, and improve the overall project progress.

[0082] The technical solution of the present invention will be further described in detail below through the drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 It is a module schematic diagram of a dynamic adaptive and multi - physical - field - coupled coal roadway impact test system of the present invention;

[0084] Figure 2 It is a schematic diagram of a coal roadway driving model and an impact module of a dynamic adaptive and multi - physical - field - coupled coal roadway impact test system of the present invention;

[0085] Figure 3Schematic diagram of the coal roadway driving model structure of a coal roadway impact test system with dynamic adaptability and multi-physical field coupling according to the present invention;

[0086] Figure 4 Schematic diagram of the impact module of a coal roadway impact test system with dynamic adaptability and multi-physical field coupling according to the present invention;

[0087] Figure 5 Schematic diagram of the coal flow process of a coal roadway impact test method with dynamic adaptability and multi-physical field coupling according to the present invention.

[0088] Reference numerals

[0089] 1. Coal roadway driving model, 2. Propulsion oil cylinder, 3. Coal roadway driving inlet, 4. Variable stiffness spring, 5. Electromagnetic vibrator, 6. Adjusting support, 7. Installation plate, 8. Sliding track, 61. Position moving support, 62. Angle adjusting support, 63. Adjusting installation block. Detailed implementation manners

[0090] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0091] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0092] Embodiment

[0093] As Figures 1-4As shown in the figure, the present invention provides a coal roadway impact test system with dynamic adaptability and multi-physical field coupling, including a coal roadway driving model 1. The coal roadway driving model 1 is respectively connected to a loading device and a sensor module. The sensor module is connected to a multi-strain rate coupling feedback module, and the multi-strain rate coupling feedback module is connected to a control module. The control module is also connected to numerical simulation software and the loading device. The loading device includes an impact module, a propulsion oil cylinder 2, and a variable stiffness spring 4. The impact module is located above the coal roadway driving model. Propulsion oil cylinders 2 and variable stiffness springs 4 are arranged on the front, rear, left, right, and upper outer surfaces of the coal roadway driving model. A coal roadway driving inlet 3 is opened at the center of the right end face of the coal roadway driving model 1.

[0094] The sensor module includes a stress sensor, a strain sensor, a deformation rate sensor, a pressure sensor, a temperature sensor, and a seepage sensor. The pressure sensor is installed inside the propulsion oil cylinder and the coal roadway driving model. The stress sensor, the strain sensor, the deformation rate sensor, the temperature sensor, and the seepage sensor are all installed inside the coal roadway driving model.

[0095] The multi-strain rate coupling feedback model includes a data acquisition card, a signal conditioning circuit, and a microprocessor;

[0096] The data acquisition card is used to receive the analog signals from each sensor and convert them into digital signals;

[0097] The signal conditioning circuit is used to preprocess the signals output by the sensors;

[0098] The microprocessor is used to control the data acquisition process, and perform preliminary processing and analysis on the acquired data

[0099] The data acquisition card, as the interface between the sensors and the system, receives the analog electrical signals from the stress sensor, the strain sensor, etc. The characteristics such as the amplitude and frequency of the analog signal are related to the measured physical quantity, but the analog signal is prone to interference during transmission and processing and is not convenient for direct computer processing. The data acquisition card converts the analog signal into a digital signal through analog-to-digital conversion technology. The digital signal has the advantages of strong anti-interference ability, easy storage, and calculation.

[0100] The signal conditioning circuit preprocesses the signals output by the sensors, including operations such as amplification, filtering, and isolation. The amplification operation can enhance the amplitude of the weak signal, making it easier for subsequent processing; filtering removes the noise and interference components in the signal, improving the signal quality; isolation prevents mutual interference between different circuits. The microprocessor controls the data acquisition process for the preprocessed and converted digital signals, acquires data according to the preset sampling frequency and time interval, and performs preliminary processing and analysis on the acquired data, such as calculating statistical features such as the average value and variance of the data, and detecting outliers in the data, providing a reliable data source for subsequent system state evaluation.

[0101] The control module includes a communication module, a control computer, a data storage device, and control algorithm software;

[0102] The communication module is used to communicate and transmit with the multi-strain rate coupling feedback module and the numerical simulation software;

[0103] The control computer is used to run the control algorithm and data processing software, and receive data from the multi-strain rate coupling feedback module;

[0104] The data storage device is used to store the collected data, system operation parameters, and information of the control algorithm;

[0105] The control algorithm software is used to run the algorithm program.

[0106] The communication module establishes a communication bridge between the control module, the multi-strain rate coupling feedback module, and the numerical simulation software. It ensures that data can be accurately and quickly transmitted between modules. The communication protocol and technology adopted guarantee the stability and reliability of data transmission. The control computer runs the control algorithm and data processing software, receives real-time data from the multi-strain rate coupling feedback module, and uses the built-in algorithm program to deeply analyze the data, such as calculating the rock deformation stage according to the stress-strain relationship and evaluating the stability of the coal roadway. The data storage device stores various types of collected data, including sensor data, system operation parameters, and information related to the control algorithm. These data are not only used for analyzing the current system operation state but also provide historical data support for subsequent system optimization and fault troubleshooting. The control algorithm software is the core of the control module. It contains a series of algorithm programs for realizing dynamic adaptive control, such as algorithms for adjusting loading parameters according to the rock deformation stage and algorithms related to multi-physical field coupling calculation. Through the operation of the control computer, it realizes the intelligent control of the entire coal roadway tunneling impact system.

[0107] The impact module includes a mounting plate 7, an electromagnetic vibrator 5, and an adjustment bracket 6. A sliding track 8 is provided at the bottom of the mounting plate 7. The adjustment bracket 6 is installed on the sliding track 8 and is connected to the electromagnetic vibrator 5. The adjustment bracket 6 includes a position movement bracket 61, an angle adjustment bracket 62, and an adjustment mounting block 63 connected in sequence. The electromagnetic vibrator 5 is connected to the adjustment mounting block 63 through a rotating shaft.

[0108] The coal roadway driving model 1 is the core research object of the entire system. The loading device is connected to the coal roadway driving model 1 and is used to apply external forces to simulate the impact situation during the actual driving process. The sensor module is installed on the coal roadway driving model and related positions and is responsible for collecting various physical quantity information of the model during the loading process. The multi-strain rate coupling feedback module receives the sensor data, performs signal conversion and preliminary processing, and provides an accurate data basis for subsequent analysis. The control module generates control instructions according to the processing results of the multi-strain rate coupling feedback module, combines the built-in algorithm, dynamically adjusts the loading device, and interacts with the numerical simulation software to achieve the intelligent control and optimization of the entire system.

[0109] The electromagnetic shaker 5 in the impact module generates an impact under the command of the control module. It is installed on an adjustable bracket. By moving the position bracket 51 and the angle adjustment bracket 52, the position and angle of the electromagnetic shaker 5 can be changed, so as to realize the impact simulation in different directions and positions to meet the requirements of different coal roadway driving scenarios. The propulsion cylinder 2 and the variable stiffness spring 4 are arranged around the coal roadway driving model. The propulsion cylinder 2 provides a stable thrust, and the variable stiffness spring 4 can change its own stiffness according to the deformation of the model. They work together to simulate the constraint conditions of the surrounding rocks of the coal roadway. Each type of sensor in the sensor module performs its own functions. The stress sensor measures the internal stress change of the coal and rock, the strain sensor monitors the deformation degree, the deformation rate sensor captures the speed of deformation, the pressure sensor monitors the pressure of the propulsion cylinder and the inside of the model, and the temperature sensor and the seepage sensor respectively obtain the temperature field and seepage field information. These data combined can comprehensively reflect the physical state changes during the coal roadway driving process.

[0110] As Figure 5 shown, a coal roadway impact test method with dynamic adaptability and multi-physical field coupling includes the following steps:

[0111] S1. System initialization: Set the initial parameters of the electromagnetic shaker and the oil cylinder propulsion device, calibrate each sensor, start the multi-strain rate coupling feedback module, the intelligent control module, and the numerical simulation software, and establish a communication connection between each module;

[0112] S2. Data acquisition and preliminary processing: The multi-strain rate coupling feedback module collects the data of each sensor according to the preset sampling frequency, performs signal conditioning, analog-to-digital conversion, data verification, and preliminary analysis and processing on the data to obtain the real-time data of each sensor and the corresponding change rate, and transmits the collected data to the intelligent control module in real time for storage and processing;

[0113] S3. System state evaluation and control instruction generation. The intelligent control module receives the data processed by the multi-strain rate coupling feedback module, calculates the stiffness K value and its change rate of the system according to the built-in algorithm, and compares and analyzes the current system state with the preset target state (including the stiffness K range, temperature field range, seepage field range, etc. at different stages). Control instructions are generated according to the control algorithm, such as adjusting the static load pressure of the propulsion cylinder, triggering the electromagnetic vibrator to apply dynamic load, adjusting the position and angle of the electromagnetic vibrator, etc.;

[0114] S4. Loading parameter adjustment and simulation calculation. The intelligent control module sends the control instructions to the corresponding loading equipment, and the loading equipment adjusts the loading parameters according to the instructions. The propulsion cylinder adjusts the static load pressure, and the electromagnetic vibrator applies dynamic load at the appropriate time. At the same time, the intelligent control module transmits the data to the numerical simulation software, and the numerical simulation software performs multi-physical field coupling calculation, simulates the physical field change and evaluates the stability of the coal roadway.

[0115] S5. Result feedback and optimization. The intelligent control module compares and evaluates the simulation results with the actual monitoring data (the actual deformation measured by the displacement sensor and the actual stress measured by the stress sensor). Calculate the mean absolute error MAE and the root mean square error RMSE. If the error is large, analyze the model parameter error, the physical field coupling relationship error and the sensor measurement error, adjust the relevant parameters and recalculate and optimize, continuously improving the system control accuracy and stability.

[0116] In step S2, after the system starts, the data acquisition system collects the mechanical response data and the physical field parameter data according to the preset acquisition frequency, and transmits the collected data to the intelligent control module for storage and processing in real time.

[0117] In step S3, the steps for calculating the stiffness K and its change rate are as follows:

[0118] Calculate the stiffness K:

[0119] Calculate the stiffness K according to the formula K = F / ΔL. During the calculation process, the loading force F measured by the pressure sensor and the deformation amount ΔL measured by the strain sensor are monitored in real time;

[0120] If data anomalies are detected, start the data verification and correction program; data verification uses the parity check method to append a parity bit during data transmission (in odd parity, the number of "1"s in the data bit and the parity bit is odd; in even parity, the number of "1"s is even), and the receiving end determines whether the data is correct according to the verification rule;

[0121] If the data is incorrect, correct it using the corresponding error correction algorithm according to the error type (such as single-bit error, multi-bit error, etc.). The present invention uses the Hamming code error correction algorithm.

[0122] Calculate the change rate of stiffness K

[0123] Adopt the sliding window method to calculate the change rate of stiffness K The calculation formula is as follows:

[0124]

[0125] Wherein, K(t) is the stiffness at the current moment, K(t - Δt) is the stiffness at the previous moment, and Δt is the time interval;

[0126] The size of the sliding window is set according to the requirements of the system response speed and data stability. During the calculation process, the K values at each time point are stored and updated to ensure the accuracy of the calculation.

[0127] In step S3, judging the stage where the coal roadway is located includes judging the elastic change stage and the plastic deformation stage, which are specifically as follows:

[0128] Judgment of the elastic change stage

[0129] Set the elastic modulus range as [E min , E max . When the calculated stiffness K satisfies K≈constant, the constant judgment adopts the relative error method:

[0130]

[0131] Wherein, K prev is the stiffness at the previous moment, κ is the set relative error threshold, and when E min <K<E max , it is judged that the coal roadway is in the elastic deformation stage;

[0132] Judgment of the plastic deformation stage

[0133] When the stiffness K begins to decrease, K(t) < K(t - Δt) and lasts for a certain time, and the deformation rate gradually increases, where the deformation rate

[0134] By calculating the change rate of the deformation rate

[0135] When and lasts for a certain time, it indicates that the coal roadway enters the plastic deformation stage;

[0136] When in the elastic deformation stage - the stress is less than the safety stress threshold:

[0137] Preset the safety stress threshold σ safe , and the calculation formula is as follows:

[0138] σ safe =kξsafe ;

[0139] Among them, k is the elastic modulus, and ξ safe is the safety strain threshold; when the stress σ = Kξ < Kξ safe at this time, increase the static load pressure at a preset loading rate , and its expression is

[0140]

[0141] where r is the loading rate coefficient and P is the current static load pressure. (r is determined according to the requirements of the coal roadway driving speed and the characteristics of coal and rock)

[0142] When in the elastic deformation stage - when the stress is close to the safety stress threshold:

[0143] When the stress σ satisfies σ safe -δ < σ < σ safe +δ, keep the static load pressure unchanged and appropriately increase the dynamic load frequency;

[0144] where δ is the judgment range close to the threshold; (the increase amount of the dynamic load frequency Δf is determined according to the stability analysis of the coal roadway and experimental experience)

[0145] Plastic deformation stage:

[0146] When it is judged that the coal roadway enters the plastic deformation stage, reduce the dynamic load frequency;

[0147] The dynamic load frequency reduction coefficient c is determined according to the plastic deformation characteristics of coal and rock, and the new dynamic load frequency is as follows:

[0148] f new = f prev (1 - c);

[0149] where f prev is the previous dynamic load frequency, and at the same time reduce the dynamic load magnitude. The calculation formula for the dynamic load magnitude is:

[0150]

[0151] where d is the coefficient for adjusting the dynamic load magnitude according to the deformation rate, is the deformation rate.

[0152] Input the temperature field data T(x, y, z, t) collected by the temperature sensor, the seepage velocity v(x, y, z, t) collected by the seepage sensor, and the seepage pressure p s (x, y, z, t) into the numerical simulation software, where x, y, z are the spatial coordinates in the model and t is the time;

[0153] Construct a multi - physical - field coupling model, considering the actual geometry and size of the coal roadway and the physical and mechanical properties of the surrounding rock;

[0154] Set the initial conditions of the temperature field and seepage field, the initial temperature distribution T0(x, y, z), the initial seepage velocity v0(x, y, z) and the seepage pressure p s0 (x, y, z); The boundary condition is that the temperature at the model boundary is constant T b , and the seepage velocity is zero v b = 0;

[0155] Use numerical calculation methods such as the finite element method or the finite difference method in the numerical simulation software to perform multi - physical - field coupling calculations;

[0156] When calculating the stress field, consider the thermal stress σ T = Eα T ΔT generated by the temperature field and the seepage body force generated by the seepage field where ΔT = T - T0 is the temperature change, is the seepage pressure gradient, is the gradient operator;

[0157] The stress equilibrium equation is

[0158] where θ is the total stress tensor, ρ is the density, and a is the body force;

[0159] Analyze the stability of the coal roadway under the multi - physical - field coupling action:

[0160] First, calculate the safety factor

[0161] where θ c is the uniaxial compressive strength of the coal and rock, and θ max is the calculated maximum principal stress; When FOS < 1, it indicates that the coal roadway is in an unstable state. At this time, the intelligent control module will take corresponding emergency control measures, such as immediately stopping loading, issuing an alarm, etc.;

[0162] Finally, feedback the evaluation results to the control system and the simulation calculation module.

[0163] Therefore, the present invention adopts the above - mentioned coal roadway impact test system and method of dynamic self - adaptation and multi - physical - field coupling. By using the sensor module to collect various data in real - time, the multi - strain - rate coupling feedback module and the control module work together to achieve dynamic self - adaptation control of the loading equipment. At the same time, considering the multi - physical - field coupling effect, through accurate calculation and analysis by numerical simulation software, it can more accurately evaluate the stability during the coal roadway driving process, improve the safety and efficiency of driving, and reduce the occurrence of engineering accidents.

[0164] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions of the present invention or make equivalent replacements, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A coal roadway impact test system with dynamic adaptability and multi-physical field coupling, characterized in that: It includes a coal roadway driving model, which is respectively connected to a loading device and a sensor module. The sensor module is connected to a multi-strain rate coupling feedback module, and the multi-strain rate coupling feedback module is connected to a control module. The control module is also connected to numerical simulation software and the loading device. The loading device includes an impact module, a propulsion oil cylinder, and a variable stiffness spring. The impact module is located above the coal roadway driving model. Propulsion oil cylinders and variable stiffness springs are arranged on the front, rear, left, right, and upper outer surfaces of the coal roadway driving model. A coal roadway driving entrance is opened at the center of the right end face of the coal roadway driving model. The material of the variable stiffness spring is alloy spring steel.

2. The dynamic adaptive and multi-physical field coupled coal roadway impact test system according to claim 1, wherein: The sensor module includes a stress sensor, a strain sensor, a deformation rate sensor, a pressure sensor, a temperature sensor, and a seepage sensor. The pressure sensor is installed inside the propulsion oil cylinder and the coal roadway driving model. The stress sensor, the strain sensor, the deformation rate sensor, the temperature sensor, and the seepage sensor are all installed inside the coal roadway driving model.

3. A dynamic adaptive and multi-physical field coupled coal roadway impact test system and method according to claim 1, characterized in that: The multi-strain rate coupling feedback model includes a data acquisition card, a signal conditioning circuit, and a microprocessor. The data acquisition card is used to receive analog signals from each sensor and convert them into digital signals. The signal conditioning circuit is used to preprocess the signals output by the sensors. The microprocessor is used to control the data acquisition process, and perform preliminary processing and analysis on the acquired data.

4. A coal roadway impact test system with dynamic adaptability and multi-physical field coupling according to claim 1, characterized in that: The control module includes a communication module, a control computer, a data storage device, and control algorithm software. The communication module is used to communicate and transmit with the multi-strain rate coupling feedback module and the numerical simulation software. The control computer is used to run the control algorithm and data processing software, and receive data from the multi-strain rate coupling feedback module. The data storage device is used to store the acquired data, system operation parameters, and information of the control algorithm. The control algorithm software is used to run algorithm programs, including algorithms for adjusting loading parameters according to the change of stiffness K, algorithms related to multi-physical field coupling calculation, etc., to realize the intelligent control of the entire coal roadway driving impact system.

5. A coal roadway impact test system with dynamic adaptability and multi-physical field coupling according to claim 1, characterized in that: The impact module includes a mounting plate, an electromagnetic vibrator, and an adjustment bracket. A sliding track is arranged at the bottom of the mounting plate. The adjustment bracket is installed on the sliding track and connected to the electromagnetic vibrator. The adjustment bracket includes a position movement bracket, an angle adjustment bracket, and an adjustment mounting block connected in sequence. The electromagnetic vibrator is connected to the adjustment mounting block through a rotating shaft. The position movement bracket realizes displacement in the horizontal direction through the cooperation of a high-precision ball slider and the sliding track. The angle adjustment bracket adopts a high-strength stainless steel joint structure to realize angle adjustment in the vertical plane.

6. A dynamic adaptive and multi-physical field coupling coal roadway impact test method is applied to the dynamic adaptive and multi-physical field coupling coal roadway impact test system according to any one of claims 1-5, characterized in that: It includes the following steps: S1. System initialization, set the initial parameters of the electromagnetic vibrator and the oil cylinder propulsion device, calibrate each sensor, start the multi-strain rate coupling feedback module, the intelligent control module, and the numerical simulation software, and establish communication connections between each module. S2. Data acquisition and preliminary processing: The multi-strain rate coupling feedback module collects data from each sensor at a preset sampling frequency, performs signal conditioning, analog-to-digital conversion, data verification, and preliminary analysis on the data to obtain real-time sensor data and corresponding change rates, and transmits the collected data to the intelligent control module in real time for storage and processing; S3. System state evaluation and control instruction generation: For the stiffness K value and its change rate, compare and analyze the current system state with the preset target states, including the stiffness K range, temperature field range, and seepage field range at different stages, and generate control instructions according to the control algorithm; S4. Loading parameter adjustment and simulation calculation: The intelligent control module sends the control instructions to the corresponding loading devices. The loading devices adjust the loading parameters according to the instructions to achieve dynamic adaptive control; the propulsion cylinder adjusts the static load pressure, and the electromagnetic vibrator applies dynamic load at the appropriate time. At the same time, the intelligent control module transmits the data to the numerical simulation software, and the numerical simulation software performs multi-physical field coupling calculations, simulates the physical field changes, and evaluates the stability of the coal roadway; S5. Result feedback and optimization: The numerical simulation software feeds back the calculation results to the intelligent control module. The intelligent control module further optimizes the control strategy and operation parameters according to the simulation results and the actual system state.

7. A dynamic adaptive and multi-physical field coupled coal roadway impact test method according to claim 6, characterized in that: In step S2, after the system is started, the data acquisition system collects mechanical response data and physical field parameter data at the preset acquisition frequency, and transmits the collected data to the intelligent control module in real time for storage and processing.

8. A dynamic adaptive and multi-physical field coupling coal roadway impact test method according to claim 6, characterized in that: In step S3, the steps of the algorithm in the intelligent control module for calculating the stiffness K and its change rate are as follows: Calculating the stiffness K: Calculate the stiffness K according to the formula K = F / ΔL. During the calculation process, the loading force F measured by the pressure sensor and the deformation amount ΔL measured by the strain sensor are monitored in real time; If abnormal data is detected, start the data verification and correction program; Data verification uses the parity check method to append a parity bit during data transmission (in odd parity, the number of "1"s in the data bits and the parity bit is odd; in even parity, the number of "1"s is even). The receiving end judges whether the data is correct according to the verification rules; If the data is incorrect, use the corresponding error correction algorithm to correct it according to the error type (such as single-bit error, multi-bit error, etc.); Calculate the change rate of stiffness K The change rate of stiffness K is calculated using the sliding window method The calculation formula is as follows: Among them, K(t) is the stiffness at the current moment, K(t - Δt) is the stiffness at the previous moment, and Δt is the time interval; The sliding window size is set according to the system response speed and data stability requirements. During the calculation process, the K value at each time point is stored and updated to ensure the accuracy of the calculation.

9. A dynamic adaptive and multi-physical field coupled impact test method for coal roadway according to claim 6, characterized in that: In step S3, in step S3, judging the stage where the coal roadway is located includes judging the elastic change stage and the plastic deformation stage, which are specifically as follows: Judging the elastic change stage Set the elastic modulus range to be [E min , E max . When the calculated stiffness K satisfies K≈constant, the constant judgment adopts the relative error method: Among them, K prev is the stiffness at the previous moment, κ is the set relative error threshold, E min <K<E max When this condition is met, it is judged that the coal roadway is in the elastic deformation stage; Judging the plastic deformation stage When the stiffness K begins to decrease, K(t) < K(t - Δt) and persists for a certain period of time, and the deformation rate gradually increases, where the deformation rate By calculating the rate of change of the deformation rate When and lasts for a certain period of time, it indicates that the coal roadway enters the plastic deformation stage; When in the elastic deformation stage - the stress is less than the safety stress threshold: Preset safety stress threshold σ safe , and the calculation formula is as follows: σ safe = kξ safe ; where k is the elastic modulus and ξ safe is the safety strain threshold; when the stress σ = Kξ < Kξ safe , increase the static load pressure at a preset loading rate , and its expression is Among them, r is the loading rate coefficient, and P is the current static load pressure; (r is determined according to the coal roadway driving speed requirement and the coal and rock properties) When in the elastic deformation stage - the stress is close to the safety stress threshold: When the stress σ satisfies σ safe -δ < σ < σ safe +δ, keep the static load pressure unchanged and appropriately increase the dynamic load frequency; where δ is the range close to the threshold judgment; (the increase in dynamic load frequency Δf is determined according to the stability analysis and experimental experience of the coal roadway) Plastic deformation stage: When it is judged that the coal roadway enters the plastic deformation stage, the dynamic load frequency is reduced; The reduction coefficient c of the dynamic load frequency is determined according to the plastic deformation characteristics of the coal and rock, and the new dynamic load frequency is as follows: f new = f prev (1 - c); where f prev is the previous dynamic load frequency, and at the same time, the magnitude of the dynamic load is reduced. The calculation formula for the magnitude of the dynamic load is: where d is the coefficient for adjusting the dynamic load according to the deformation rate, is the deformation rate. Input the temperature field data T(x, y, z, t) collected by the temperature sensor, the seepage velocity v(x, y, z, t) and the seepage pressure p s (x, y, z, t) collected by the seepage sensor into the numerical simulation software, where x, y, z are the spatial coordinates within the model, and t is the time; Construct a multi-physical field coupling model, considering the actual geometric shape and size of the coal roadway and the physical and mechanical properties of the surrounding rock; Set the initial conditions of the temperature field and the seepage field, including the initial temperature distribution T0(x, y, z), the initial seepage velocity v0(x, y, z), and the seepage pressure p s0 (x, y, z); The boundary condition is that the temperature at the model boundary is constant T b , and the seepage velocity is zero v b = 0; The numerical simulation software performs multi-physical field coupling calculations using numerical calculation methods such as the finite element method or the finite difference method; When calculating the stress field, the thermal stress σ caused by the temperature field is considered T = Eα T ΔT and the seepage body force F generated by the seepage field s = -K▽p, where ΔT = T - T0 is the temperature change is the seepage pressure gradient is the gradient operator The stress balance equation is where θ is the total stress tensor, ρ is the density, and a is the body force; Analyze the stability of the coal roadway under the action of multi-physical field coupling: First, calculate the safety factor where, θ c is the uniaxial compressive strength of coal and rock, and θ max is the calculated maximum principal stress; when FOS < 1, it indicates that the coal roadway is in an unstable state, and at this time the intelligent control module will take corresponding emergency control measures.

10. A dynamic adaptive and multi-physical field coupled impact test method for coal roadway according to claim 6, characterized in that: In step S5, compare the coal roadway deformation δ sim (x, y, z) and stress distribution δ sim (x, y, z) calculated by the numerical simulation software with the actual deformation δ real (x, y, z) measured by the displacement sensor and the actual stress δ real (x, y, z) measured by the stress sensor, and the specific steps are as follows: Calculate the mean absolute error MAE: Deformed Mean Absolute Error Stress mean absolute error where n is the number of monitoring points; Calculate the root mean square error RMSE: Deformation root mean square error Root mean square error of stress If MAE and RMSE are large, it indicates that there is a large deviation between the simulation results and the actual situation. At this time, analyze the model parameter error, the physical field coupling relationship error, and the sensor measurement error; Finally, feedback the evaluation results to the control system and the simulation calculation module.

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