A coal mine drilling rock mechanics parameter testing system and method

Abstract

This invention relates to the field of underground geological exploration technology in coal mines, and provides a coal mine borehole rock mechanical parameter testing system and method. The coal mine borehole rock mechanical parameter testing system includes: a main unit; a rock parameter testing probe electrically connected to the main unit, and the rock parameter testing probe is equipped with an orientation measuring device; and a push rod, the end of which is connected to the rock parameter testing probe for driving the rock parameter testing probe into a test borehole in the surrounding rock of the roadway. This invention can simultaneously measure multiple rock mechanical parameters in a single test, providing comprehensive data on the mechanical properties of the surrounding rock, reducing testing time and cost, and improving testing efficiency. During the test, measurements are accurately performed in multiple different directions, covering all directions around the borehole circumference, enabling comprehensive acquisition of the mechanical parameters of the surrounding rock in different directions, and more realistically reflecting the overall mechanical properties of the surrounding rock.

Description

Technical Field

[0001] This invention relates to the field of underground geological exploration technology in coal mines, and in particular to a system and method for testing the rock mechanical parameters of coal mine boreholes. Background Technology

[0002] The theory and technology of roadway support have always been the core research content of coal mine rock strata control. Rock bolt support has the advantages of low cost and reliable support performance, and has become the main support form of coal mine roadways.

[0003] However, due to the complex geological conditions of coal mine roadways and the lack of sufficient understanding of the mechanism of rock bolt support, the quality of rock bolt support projects is difficult to control, and related engineering accidents often occur. The main reason for the unsatisfactory status of roadway surrounding rock support is the lack of systematic and reliable support design methods.

[0004] Currently, common methods for coal mine roadway support design in my country include engineering analogy, theoretical analysis, and field monitoring. Among these, engineering analogy is the most widely used. However, in practice, new roadways are often simply designed based on the support schemes of similar roadways from the past, rarely considering the changes and impacts of engineering geological conditions. Even when technicians consider the differences in engineering geological conditions, they cannot conduct quantitative analysis and can only adjust the support based on their subjective experience. Fundamentally, a support design method based on geological conditions is key to solving roadway stability control, and rapid, quantitative, and accurate evaluation of the surrounding rock geological conditions is the breakthrough point for solving the theoretical and technical problems of this method.

[0005] However, the current methods for assessing the geological conditions of the surrounding rock in coal mine roadways are limited. They mainly rely on geological profiles provided by surface boreholes and core testing of the rock mass exposed at the tunnel face. The number of test parameters is small, and the accuracy of the geological parameters provided is low, which cannot meet the needs of support design.

[0006] Therefore, if multiple mechanical parameters can be tested in situ from underground boreholes in coal mines, and the rock quality, acoustic parameters, strength parameters, dynamic elastic parameters, and static elastic parameters of the surrounding rock in the borehole roadway can be tested from multiple aspects to analyze and evaluate the rock, information on the rock mass occurrence state can be obtained more effectively. This is undoubtedly of great significance for the support design of the roadway and the safe production of the coal mine. Summary of the Invention

[0007] This invention provides a system and method for testing rock mechanical parameters in coal mine boreholes. By using this device to load test the rock mass in coal mine roadways, rock mechanical parameters at different depths and angles of the test boreholes can be obtained. This is beneficial for designing effective support schemes during construction, ensuring support strength and project stability.

[0008] This invention provides a coal mine borehole rock mechanical parameter testing system, comprising:

[0009] Host;

[0010] A rock parameter testing probe, which is electrically connected to the main unit, and the rock parameter testing probe is equipped with an orientation measuring device;

[0011] A push rod, the end of which is connected to the rock parameter testing probe, is used to drive the rock parameter testing probe into a test borehole in the surrounding rock of the roadway.

[0012] According to the coal mine borehole rock mechanical parameter testing system provided by the present invention, the rock parameter testing probe is equipped with a camera, which is electrically connected to the host computer and is used to acquire images of the test borehole in order to analyze the lithology, rock structure, geological structure and damage degree of the surrounding rock of the roadway.

[0013] According to the coal mine borehole rock mechanical parameter testing system provided by the present invention, the rock parameter testing probe is equipped with an acoustic wave sensor, which is electrically connected to the host computer and is used to detect the acoustic wave velocity of the surrounding rock of the test borehole and to send the acoustic wave velocity to the host computer to calculate the dynamic elastic modulus, Poisson's ratio and shear modulus of the surrounding rock of the test borehole.

[0014] The rock mechanical parameter testing system for coal mine boreholes provided by the present invention includes the following:

[0015] thimble;

[0016] The system includes a drive mechanism and a displacement sensor. The drive mechanism acts on the ejector pin to drive it into the surrounding rock of the test borehole under the control of the host computer. The displacement sensor is electrically connected to the host computer and is used to measure the displacement of the ejector pin.

[0017] According to the coal mine borehole rock mechanical parameter testing system provided by the present invention, the driving mechanism includes: a hydraulic cylinder, which acts on the ejector pin to drive the ejector pin to move axially;

[0018] A stepper motor acts on the hydraulic cylinder to drive the hydraulic cylinder to move.

[0019] The coal mine borehole rock mechanical parameter testing system provided by the present invention further includes a hydraulic sensor, which is disposed on the oil cylinder and is used to detect the pressure exerted by the oil cylinder on the plunger.

[0020] According to the coal mine borehole rock mechanical parameter testing system provided by the present invention, the orientation measuring device is a three-dimensional compass.

[0021] Secondly, the present invention provides a method for testing the mechanical parameters of rocks in coal mine boreholes, comprising the following steps:

[0022] Electrically connect the main unit to the rock parameter test probe, and use the push rod to advance the rock parameter test probe to the test point of the test borehole;

[0023] Read the current value of the azimuth measuring device, rotate the rock parameter testing probe by rotating the push rod around the axis, adjust the value of the azimuth measuring device to 0 degrees, and use the rock parameter testing probe to measure the surrounding rock parameters of the borehole wall at the current angle;

[0024] After the measurement is completed, by reading the value of the orientation measuring device, the push rod is controlled to rotate the rock parameter test probe 120 degrees and 240 degrees in sequence along the first direction relative to the 0-degree position, and the surrounding rock parameters of the borehole wall in the test borehole are measured at 120 degrees and 240 degrees respectively using the rock parameter test probe.

[0025] Once the rock parameter data of the test borehole in the three directions at the current test point have been tested, the rock parameter test probe is pushed to the next test point until the depth test of the entire test borehole is completed.

[0026] The quality of the surrounding rock in the tunnel is comprehensively analyzed based on the parameters of the surrounding rock of the borehole wall.

[0027] According to the method for testing rock mechanical parameters in coal mine boreholes provided by the present invention, the step of measuring the borehole wall surrounding rock parameters at the current angle using the rock parameter testing probe includes:

[0028] The camera of the rock parameter testing probe acquires images of the test borehole and transmits the image data to the host computer.

[0029] The stepper motor is controlled to press the ejector pin into the surrounding rock of the test borehole. During the process of pressing the ejector pin into the surrounding rock of the test borehole, the pressure value of the hydraulic sensor and the displacement value of the displacement sensor are measured, and the obtained pressure value and displacement value are transmitted to the host.

[0030] The acoustic wave sensor contacts the surrounding rock of the test borehole and performs acoustic wave testing, and the acquired acoustic wave data is transmitted to the host computer.

[0031] The probe and the acoustic sensor are controlled to retract into the rock parameter testing probe to complete the measurement of the surrounding rock parameters of the borehole wall at the current angle.

[0032] According to the method for testing rock mechanical parameters in coal mine boreholes provided by the present invention, the step of comprehensively analyzing the quality of the surrounding rock of the roadway based on the parameters of the borehole wall includes:

[0033] The lithology, rock structure, and geological structure of the surrounding rock in the test borehole are obtained from images captured by the camera.

[0034] Based on the data obtained from the acoustic sensor, displacement sensor, and hydraulic sensor, the longitudinal wave velocity, transverse wave velocity, dynamic elastic modulus, dynamic shear modulus, Poisson's ratio, static compression modulus, and uniaxial compressive strength of the surrounding rock in the tunnel are analyzed.

[0035] According to the method for testing the rock mechanical parameters of coal mine boreholes provided by the present invention, the quality of the surrounding rock of the roadway The calculation formula is:

[0036] ;

[0037] in: It is the dynamic elastic modulus; It is the dynamic shear modulus; d Poisson's ratio; It is the static elastic modulus; denoted as uniaxial compressive strength; m represents the degree of damage to the surrounding rock of the roadway.

[0038] This invention provides a method for testing rock mechanical parameters in coal mine boreholes. It comprehensively analyzes and evaluates the mechanical parameters of roadway rock masses. Compared to existing technologies, the rock parameter testing probe integrates multiple sensors, enabling simultaneous measurement of various rock mechanical parameters in a single test. This provides comprehensive data on the mechanical properties of the surrounding rock, reducing testing time and cost, and improving testing efficiency. During the test, an orientation measurement device ensures the probe's accurate position and orientation within the borehole, accurately achieving measurements in multiple directions. This covers all directions around the borehole circumference, comprehensively acquiring the mechanical parameters of the roadway surrounding rock in different orientations. This avoids errors that may occur with single-direction measurements, ensuring more comprehensive and accurate test results that more realistically reflect the overall mechanical properties of the surrounding rock. The drive mechanism precisely controls the insertion depth and pressure of the probe, achieving high-precision measurement and ensuring the accuracy of the test data, providing a reliable basis for the quality assessment of the roadway surrounding rock.

[0039] In addition, the rock parameter testing probe communicates with the host in real time. The host can receive and process the data collected by the probe in real time, and evaluate the geological conditions of the tunnel in real time. The evaluation results can be given on site, and the geological evaluation results are not affected by human factors. All evaluation results are calculated and statistically analyzed based on the test data. By measuring the mechanical parameters of the surrounding rock of the tunnel, data support is provided for geological exploration, and the stability and support requirements of the surrounding rock are determined. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram illustrating the working process of testing rock mechanical parameters in coal mine boreholes according to an embodiment of the present invention.

[0042] Figure 2 A circuit functional diagram of a rock parameter testing probe provided in an embodiment of the present invention;

[0043] Figure 3 This is a structural block diagram of a rock parameter testing probe provided in an embodiment of the present invention;

[0044] Figure 4 A host functional diagram provided for an embodiment of the present invention;

[0045] Figure 5 This is one of the test borehole imaging effect diagrams provided in the embodiments of the present invention;

[0046] Figure 6 This is the second example of a test borehole imaging effect diagram provided in an embodiment of the present invention;

[0047] Figure 7 This is a diagram illustrating the acoustic wave test results of the surrounding rock in the test borehole, provided in an embodiment of the present invention.

[0048] Figure 8 The strength modulus curve of the surrounding rock in the test borehole is provided for an embodiment of the present invention.

[0049] Figure label:

[0050] 1. Host; 11. Second network port; 12. Central processing unit; 13. System bus; 14. Human-computer interaction device; 15. Secondary memory; 16. Power supply;

[0051] 2. Rock parameter testing probe; 21. Circuit board; 211. Receiving control and processing circuit; 212. Microcontroller; 213. First memory; 214. First network port;

[0052] 22. Camera; 23. Hydraulic sensor; 24. Pin; 25. Drive mechanism; 26. Acoustic sensor; 27. 3D compass;

[0053] 3. Push rod; 4. Test borehole; 5. Surrounding rock of the tunnel; 6. Tunnel; 7. Communication cable. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0055] Rock mass strength can be obtained through laboratory or in-situ testing. However, laboratory tests use rock blocks detached from the rock mass, making it difficult to accurately simulate and reflect the actual state of the rock mass underground, such as stress environment, structural plane distribution, and other underground environmental factors. Therefore, laboratory rock block strength data often deviates significantly from the actual underground rock mass conditions, generally being too high for engineering purposes. In reality, most rock masses contain weak structural planes or interlayers, and coal seams generally have low strength. Coal-bearing strata also frequently contain rocks with very low strength, making it difficult to prepare specimens. Therefore, the best method is to measure various mechanical properties of the rock mass in-situ to more accurately describe its mechanical properties.

[0056] Therefore, the coal mine borehole rock mechanical parameter testing technology is a technique for in-situ testing of the surrounding rock mass of coal and rock masses. It includes optical imaging testing, acoustic testing, and pressure strength testing of the surrounding rock, providing new measurement methods and data needed to improve and enhance the quality evaluation of engineering rock masses. This allows for the rapid, effective, and quantitative measurement of the uniaxial compressive strength, size, and underground distribution of rock blocks, as well as the attitude, extension, undulation, smoothness, thickness, and physical and mechanical properties of the filling material at the interface between rock blocks. It can more objectively and comprehensively determine rock parameters such as uniaxial compressive strength, rock mass quality indicators, rock mass integrity, rock hardness, rock mass stress state, and discontinuities. In underground engineering, the testing of the mechanical parameters of the surrounding rock in roadways is the basis for determining support parameters, classifying the surrounding rock, and analyzing the stability of the surrounding rock in roadways.

[0057] Based on this, the present invention provides a coal mine borehole rock mechanical parameter testing system and method. Through this device and method, parameters such as lithology, rock structure, rock acoustic velocity, dynamic elastic modulus, static elastic modulus, and rock strength of the surrounding rock 5 of the roadway can be analyzed and determined.

[0058] The following is combined with Figures 1-8 This invention describes a system and method for testing rock mechanical parameters in coal mine boreholes.

[0059] This invention provides a system for testing the mechanical parameters of rocks in coal mine boreholes, such as... Figure 1 As shown, it includes: main unit 1, rock parameter test probe 2 and push rod 3.

[0060] In this system, host 1 serves as the control center for the entire testing system, responsible for sending instructions and receiving data. Rock parameter testing probe 2 is electrically connected to host 1. For example, the testing control and data transmission of rock parameter testing probe 2 are transmitted to host 1 via communication cable 7. Rock parameter testing probe 2 is equipped with a directional measuring device, such as a three-dimensional compass 27, which can measure the angle of rock parameter testing probe 2 in real time, providing accurate directional guidance for operators. The end of push rod 3 is connected to rock parameter testing probe 2 and is used to drive rock parameter testing probe 2 into the test borehole 4 in the surrounding rock of the roadway 6 to test the rock mechanical parameters of the borehole surrounding rock in the roadway 6.

[0061] Optionally, the field host 1 is an intrinsically safe tablet computer, or an intrinsically safe mobile phone or processor, and the push rod 3 can be driven by an electric cylinder, hydraulic cylinder or pneumatic cylinder.

[0062] In this embodiment, the rock parameter testing probe 2 is equipped with a camera 22, which is electrically connected to the host 1. The camera 22 is used to acquire images of the test borehole 4 to analyze parameters such as the lithology, rock structure, and geological features of the surrounding rock 5, as well as the degree of damage to the surrounding rock. The imaging effect of the surrounding rock in the test borehole 4 is as follows: Figure 5 and Figure 6 As shown.

[0063] Furthermore, the rock parameter testing probe 2 is equipped with an acoustic sensor 26, which is electrically connected to the host 1. The acoustic sensor 26 is used to detect the acoustic velocity of the surrounding rock 5 in the test borehole 4 and to send the acoustic velocity to the host 1 to calculate the dynamic elastic modulus, Poisson's ratio, and shear modulus of the surrounding rock 5 in the test borehole 4. The acoustic effect of the test on the surrounding rock 5 is as follows: Figure 7 As shown.

[0064] In this embodiment, two acoustic wave sensors 26 are provided, and the two acoustic wave sensors 26 are arranged at intervals.

[0065] Furthermore, the rock parameter testing probe 2 is equipped with a pin 24, a drive mechanism 25, and a displacement sensor. The pin 24 applies pressure to the surrounding rock by directly contacting the borehole wall and causing deformation of the surrounding rock. The drive mechanism 25 acts on the pin 24 to drive the pin 24 into the surrounding rock of the test borehole 4 under the control of the host 1. The displacement sensor is electrically connected to the host 1 to monitor the displacement of the pin 24 in real time and transmit the data back to the host 1.

[0066] In one specific embodiment, the drive mechanism 25 includes a stepper motor and a hydraulic cylinder. The hydraulic cylinder acts on the ejector pin 24 to drive the ejector pin 24 to move axially. The stepper motor acts on the hydraulic cylinder to drive the hydraulic cylinder to move. In use, the hydraulic cylinder moves under the drive of the stepper motor, pushing the ejector pin 24 to gradually press into the surrounding rock of the test borehole 4 and apply pressure to the surrounding rock.

[0067] With this configuration, the stepper motor has high-precision position control capability, which can accurately control the movement of the hydraulic cylinder and achieve high-precision displacement and pressure control. Compared with traditional hydraulic systems, the stepper motor directly drives the hydraulic cylinder, eliminating components such as oil pipes, oil pumps, and oil tanks. The system structure is more compact, installation and maintenance are simpler, and the response speed is faster, enabling rapid start and stop. By using a stepper motor, the movement of the hydraulic cylinder can be precisely controlled, ensuring that the ejector pin 24 and displacement sensor can be pressed into the surrounding rock at a constant speed and pressure.

[0068] like Figure 2 As shown, it also includes a hydraulic sensor 23, which is mounted on the oil cylinder to detect the pressure exerted by the oil cylinder on the ejector pin 24, and to detect the values ​​of the displacement sensor and the hydraulic sensor 23 during the ejection process of the ejector pin 24. The host 1 calculates the static elastic modulus and rock strength of the surrounding rock 5 of the test borehole 4 based on the measured displacement and pressure values. The strength test results of the surrounding rock 5 are as follows: Figure 8 As shown.

[0069] During operation, as the hydraulic pressure in the cylinder increases, the pressure exerted by the ejector pin 24 on the borehole wall of the test borehole 4 continuously increases. Once the critical pressure is reached, the rock mass in the borehole wall is crushed, and the pressure of the hydraulic sensor 23 suddenly decreases. At this point, the highest pressure reading recorded by the hydraulic sensor 23 is... After conversion, the critical pressure of the rock mass at that point can be obtained. Uniaxial compressive strength of rock mass .

[0070] like Figure 2 , Figure 3 and Figure 4 As shown, the rock parameter testing probe 2 is equipped with a circuit board 21, which is used to integrate and control various electronic components in the probe. The circuit board 21 is equipped with a receiving control processing circuit 211, a microcontroller 212, a first memory 213, and a first network port 214. The host 1 is equipped with a second network port 11, a central processing unit 12, a system bus 13, a human-computer interaction device 14, and a second memory 15. The human-computer interaction device 14 refers to the hardware device used to realize information exchange and control between humans and computers, which can be common input or output devices such as keyboards and touch screens.

[0071] During operation, the host 1 sends control commands to the first network port 214 of the rock parameter testing probe 2 via the second network port 11. The probe's receiving control processing circuit 211 receives and parses the commands, and the microcontroller 212 executes the corresponding operations. The probe collects rock parameter data, processes it through the microcontroller 212, and stores the processed data in the first memory 213. The probe transmits the stored data to the host 1's second network port 11 via the first network port 214. The host 1 receives the data and stores it in the second memory 15. The host 1's central processing unit 12 further processes and analyzes the received data to generate test results. The host 1's system bus 13 is used to connect various hardware components inside the host 1 to realize the transmission of data and control signals. The user views the test results, inputs commands, and configures test parameters through the human-machine interface device 14.

[0072] This invention enables efficient and accurate on-site measurement of various mechanical properties of the surrounding rock mass 5 in a roadway. High-speed data transmission between the rock parameter testing probe 2 and the host 1 is achieved through a network port, ensuring the real-time performance and accuracy of the data. The host 1 is equipped with a central processing unit 12 and a system bus 13, which can efficiently process and analyze large amounts of data. The human-computer interaction device 14 allows users to easily operate the system and view the test results. The probe and the host 1 are each equipped with a memory to ensure the secure storage and efficient management of the data.

[0073] In this embodiment, both the host 1 and the circuit board 21 are equipped with a power supply 16, which can be a lithium battery, a solar cell, or the like.

[0074] This invention also provides a method for testing the mechanical parameters of rocks in coal mine boreholes, comprising the following steps:

[0075] S1: Connect the host 1 to the rock parameter test probe 2 electrically, and use the push rod 3 to push the rock parameter test probe 2 to the test point of the test borehole 4;

[0076] S2: Read the current value of the azimuth measuring device, rotate the push rod 3 around the axis to drive the rock parameter test probe 2 to rotate, adjust the value of the azimuth measuring device to 0 degrees, and use the rock parameter test probe 2 to measure the surrounding rock parameters of the borehole wall in the test borehole 4 at the current angle.

[0077] S3: After the measurement is completed, by reading the value of the azimuth measuring device, the push rod 3 is controlled to rotate the rock parameter test probe 2 120 degrees and 240 degrees in sequence along the first direction relative to the 0-degree position, and the rock parameter test probe 2 is used to measure the surrounding rock parameters of the borehole wall in the test borehole 4 at 120 degrees and 240 degrees respectively.

[0078] S4: After the rock parameter data of the test borehole 4 in the three directions at the current test point have been tested, push the rock parameter test probe 2 to the next test point until the depth test of the entire test borehole 4 is completed.

[0079] S5: Analyze the quality of the surrounding rock 5 in the tunnel based on the parameters of the surrounding rock of the borehole wall.

[0080] In one specific embodiment, step S2, measuring the surrounding rock parameters of the test borehole 4 at the current angle using the rock parameter testing probe 2, includes:

[0081] S21: The camera 22 of the rock parameter test probe 2 acquires an image of the test borehole 4 and transmits the image data to the host 1;

[0082] S22: The stepper motor is controlled to press the ejector pin 24 into the surrounding rock of the test borehole 4, and the pressure value of the hydraulic sensor 23 and the displacement value of the displacement sensor are measured during the process of pressing the ejector pin 24 into the surrounding rock of the test borehole 4, and the obtained pressure value and displacement value are transmitted to the host 1.

[0083] S23: The acoustic wave sensor 26 contacts the surrounding rock of the test borehole 4 and performs acoustic wave testing, and transmits the acquired acoustic wave data to the host 1.

[0084] S24: Control the pin 24 and the acoustic sensor 26 to retract into the rock parameter test probe 2 to complete the measurement of the surrounding rock parameters of the borehole wall at the current angle.

[0085] In one specific embodiment, step S5 includes:

[0086] S51: Obtain the lithology, rock structure, and geological structure of the surrounding rock of test borehole 4 based on the images captured by camera 22;

[0087] S52: Based on the data obtained from the acoustic wave sensor 26, displacement sensor and hydraulic sensor 23, calculate the longitudinal wave velocity, transverse wave velocity, dynamic elastic modulus, dynamic shear modulus, Poisson's ratio, static elastic modulus and uniaxial compressive strength of the surrounding rock 5 in the roadway.

[0088] Specifically, the quality of the surrounding rock of tunnel 5 The calculation process is as follows:

[0089] 1. First, read the longitudinal wave time from the acoustic wave test waveform. and transverse wave time Let the distance between the two acoustic sensors 26 be... ;

[0090] Then the longitudinal wave velocity:

[0091] Shear wave velocity: .

[0092] 2. Based on the longitudinal wave velocity and transverse wave velocity The dynamic elastic modulus was calculated respectively. Dynamic shear modulus Compared to Poisson ;

[0093] Poisson's ratio: ;

[0094] Dynamic elastic modulus: ;

[0095] Dynamic shear modulus: ;

[0096] in The density is the medium.

[0097] 3. The hydraulic pressure value of the hydraulic sensor 23 is read when the rock mass on the borehole wall of test borehole 4 reaches the critical pressure of the rock mass. The pressure at the end of the ejector pin 24 for:

[0098]

[0099] Where: d1 is the diameter of the cylinder piston; d2 is the diameter of the ejector pin 24.

[0100] 4. Rock mass strength is the most fundamental parameter in rock mechanics. It is an essential basic parameter for mine development, roadway layout and support, coal mining and prevention of disasters such as rockburst and coal and gas outburst. Rock mass strength includes uniaxial compressive strength, tensile strength, shear strength, triaxial compressive strength, etc. Among them, uniaxial compressive strength is a commonly used rock strength index.

[0101] The uniaxial compressive strength of coal and rock mass is expressed by the following formula:

[0102] Uniaxial compressive strength of coal and rock mass: =ks f ;

[0103] in: The critical pressure of the rock mass; ks f This is the strength conversion factor.

[0104] 5. By reading the displacement value 1 of the displacement sensor and the hydraulic value of the hydraulic sensor 23. Calculate the static elastic modulus of the rock: .

[0105] 6. Calculate the mass of the surrounding rock 5 in the tunnel. : ;

[0106] in: It is the dynamic elastic modulus; It is the dynamic shear modulus; d Poisson's ratio; It is the static elastic modulus; Uniaxial compressive strength; The degree of damage to the surrounding rock of tunnel 5.

[0107] In some specific embodiments, a method for testing rock mechanical parameters in coal mine boreholes includes the following steps:

[0108] Step S100: Connect the host 1 to the rock parameter test probe 2 via the communication cable 7, connect the push rod 3 to the rock parameter test probe 2, and use the push rod 3 to push the rock parameter test probe 2 to the test point of the borehole.

[0109] Step S200: Turn on the power 16 of the on-site host 1 to start the rock parameter testing function. The host 1 reads the value of the three-dimensional compass 27 of the rock parameter testing probe 2 through the communication cable 7. By rotating the push rod 3, the value of the three-dimensional compass 27 on the rock parameter testing probe 2 is adjusted to 0 degrees. The host 1 saves the 0-degree direction value of the three-dimensional compass 27 at this moment.

[0110] Step S300: The host 1 controls the camera 22 of the rock parameter test probe 2 to automatically acquire images in the test borehole 4 via the communication cable 7, and transmits the imaging data to the host 1 via the communication cable 7;

[0111] The host 1 controls the operation of the stepper motor to press the ejector pin 24 into the surrounding rock of the test borehole 4 at the test point. During the process of the host 1 controlling the rock parameter test probe 2 to press the ejector pin 24 into the surrounding rock of the test point, the host 1 measures the pressure value of the hydraulic sensor 23 and the displacement value of the displacement sensor, and transmits the measured pressure value and displacement value to the host 1 through the communication cable 7.

[0112] While the host 1 controls the operation of the stepper motor, it also pushes the acoustic sensor 26 out to contact the surrounding rock of the borehole at the test point. The rock parameter test probe 2 controls the acoustic sensor 26 to perform acoustic wave testing on the surrounding rock of the borehole and transmits the test acoustic wave data to the host 1 through the communication cable 7.

[0113] The host 1 controls the pin 24 and acoustic sensor 26 of the rock parameter test probe 2 to retract into the rock parameter test probe 2 via the communication cable 7.

[0114] Step S400: By reading the value of the three-dimensional compass 27 of the rock parameter test probe 2, control the push rod 3 to rotate the rock parameter test probe 2 clockwise or counterclockwise relative to the 0-degree position to the 120-degree direction, and then repeat step S300 to perform rock parameter testing in the 120-degree direction in the test borehole 4.

[0115] Step S500: By reading the value of the three-dimensional compass 27 of the rock parameter test probe 2, control the push rod 3 to rotate the rock parameter test probe 2 clockwise or counterclockwise relative to the 0-degree position to the 240-degree direction, and then repeat step S300 to perform rock parameter testing in the 240-degree direction in the test borehole 4.

[0116] Step S600: After the rock parameter data of the test borehole 4 in the three directions at the current test point have been tested, push the rock parameter test probe 2 to the next test point until the test depth of the entire test borehole 4 is completed.

[0117] Step S700: Host 1 analyzes the acoustic wave data in three directions at each test point, calculates the longitudinal wave velocity and transverse wave velocity values ​​at the test point, and calculates the dynamic elastic modulus, dynamic shear modulus, and Poisson's ratio of the rock in this test point direction based on the longitudinal wave velocity and transverse wave velocity values.

[0118] The host unit 1 analyzes parameters such as lithology, rock structure, and geological structure of the surrounding rock based on images acquired by camera 22. It also analyzes the longitudinal wave velocity, transverse wave velocity, dynamic elastic modulus, dynamic shear modulus, static compressive modulus, and uniaxial compressive strength of the surrounding rock 5 in the tunnel based on data measured by acoustic sensor 26, push pin 24, displacement sensor, stepper motor, and hydraulic cylinder. Finally, it comprehensively analyzes the quality of the surrounding rock 5 in the tunnel by combining these calculated parameters with the rock structure's properties. .

[0119] It should be noted that test points are generally set at 1-meter intervals along the drilling depth direction. Depending on the testing needs, the distance between test points can be reduced or increased.

[0120] This invention provides a method for testing rock mechanical parameters in coal mine boreholes. It comprehensively analyzes and evaluates the rock mechanical parameters of roadway 6. Compared to existing technologies, the rock parameter testing probe 2 integrates multiple sensors, enabling simultaneous measurement of various rock mechanical parameters in a single test. This provides comprehensive data on the mechanical properties of the surrounding rock, reducing testing time and cost, and improving testing efficiency. During the test, an orientation measurement device ensures the probe's accurate position and orientation within the test borehole 4, accurately achieving measurements in multiple different directions. This covers all directions around the borehole circumference, comprehensively acquiring the mechanical parameters of the roadway surrounding rock 5 in different orientations. This avoids errors that may occur with single-direction measurements, ensuring more comprehensive and accurate test results that more realistically reflect the overall mechanical properties of the surrounding rock. The drive mechanism 25 precisely controls the insertion depth and pressure of the push pin 24, achieving high-precision measurement and ensuring the accuracy of the test data, providing a reliable basis for the quality assessment of the roadway surrounding rock 5.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the mechanical parameters of rocks in coal mine boreholes, characterized in that, The testing method is implemented using a coal mine borehole rock mechanical parameter testing system, which includes: Host (1); Rock parameter testing probe (2), the rock parameter testing probe (2) is electrically connected to the host (1), and the rock parameter testing probe (2) is equipped with an orientation measuring device; Push rod (3), the end of which is connected to the rock parameter test probe (2) to drive the rock parameter test probe (2) into the test borehole (4) in the surrounding rock (5) of the roadway; The rock parameter test probe (2) is equipped with a camera (22), which is electrically connected to the host (1) to acquire images of the test borehole (4) in order to analyze the lithology, rock structure, geological structure and damage degree of the surrounding rock (5) of the tunnel. The rock parameter test probe (2) is equipped with an acoustic sensor (26), which is electrically connected to the host (1) and is used to detect the acoustic velocity of the surrounding rock (5) of the test borehole (4) and to send the acoustic velocity to the host (1) to calculate the dynamic elastic modulus, Poisson's ratio and shear modulus of the surrounding rock (5) of the test borehole (4). The testing method includes the following steps: Connect the host (1) to the rock parameter test probe (2) and use the push rod (3) to push the rock parameter test probe (2) to the test point of the test borehole (4); Read the current value of the azimuth measuring device, rotate the push rod (3) around the axis to drive the rock parameter test probe (2) to rotate, adjust the value of the azimuth measuring device to 0 degrees, and use the rock parameter test probe (2) to measure the surrounding rock parameters of the borehole wall in the test borehole (4) at the current angle; After the measurement is completed, by reading the value of the orientation measuring device, the push rod (3) is controlled to rotate the rock parameter test probe (2) 120 degrees and 240 degrees in sequence relative to the 0-degree position along the first direction, and the rock parameter test probe (2) is used to measure the surrounding rock parameters of the borehole wall in the test borehole (4) at 120 degrees and 240 degrees respectively. After the rock parameter data of the test borehole (4) in the three directions of the current test point are tested, the rock parameter test probe (2) is pushed to the next test point until the depth test of the entire test borehole (4) is completed. The quality of the surrounding rock (5) of the tunnel is comprehensively analyzed based on the parameters of the surrounding rock of the borehole wall; The measurement of the surrounding rock parameters of the test borehole (4) at the current angle using the rock parameter test probe (2) includes: The camera (22) of the rock parameter test probe (2) acquires the image of the test borehole (4) and transmits the image data to the host (1). The stepper motor is controlled to press the ejector pin (24) into the surrounding rock of the test borehole (4), and the pressure value of the hydraulic sensor (23) and the displacement value of the displacement sensor are measured during the process of pressing the ejector pin (24) into the surrounding rock of the test borehole (4), and the obtained pressure value and displacement value are transmitted to the host (1). The acoustic wave sensor (26) contacts the surrounding rock of the test borehole (4) and performs acoustic wave testing, and transmits the acquired acoustic wave data to the host (1). Control the pin (24) and the acoustic sensor (26) to retract into the rock parameter test probe (2) to complete the measurement of the surrounding rock parameters of the borehole wall at the current angle.

2. The method for testing rock mechanical parameters in coal mine boreholes according to claim 1, characterized in that, The rock parameter testing probe (2) is equipped with: thimble (24); The drive mechanism (25) and displacement sensor are provided. The drive mechanism (25) acts on the ejector pin (24) to drive the ejector pin (24) into the surrounding rock of the test borehole (4) under the control of the host (1). The displacement sensor is electrically connected to the host (1) to measure the displacement of the ejector pin (24).

3. The method for testing rock mechanical parameters in coal mine boreholes according to claim 2, characterized in that, The drive mechanism (25) includes: The hydraulic cylinder acts on the ejector pin (24) to drive the ejector pin (24) to move axially; A stepper motor acts on the hydraulic cylinder to drive the hydraulic cylinder to move.

4. The method for testing rock mechanical parameters in coal mine boreholes according to claim 3, characterized in that, It also includes a hydraulic sensor (23), which is mounted on the cylinder and is used to detect the pressure exerted by the cylinder on the ejector pin (24).

5. The method for testing rock mechanical parameters in coal mine boreholes according to claim 1, characterized in that, The comprehensive analysis of the quality of the surrounding rock (5) of the tunnel based on the parameters of the borehole wall includes: Based on the images captured by the camera (22), the lithology, rock structure, and geological structure of the surrounding rock of the test borehole (4) are obtained; Based on the data obtained from the acoustic sensor (26), the displacement sensor and the hydraulic sensor (23), the longitudinal wave velocity, transverse wave velocity, dynamic elastic modulus, dynamic shear modulus, Poisson's ratio, static elastic modulus and uniaxial compressive strength of the surrounding rock (5) of the tunnel are calculated.

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