Regulation and control system and regulation and control method

Abstract

The invention discloses a regulation and control system and a regulation and control method, the regulation and control system acts on a rock mass sample, the regulation and control system comprises a stress loading mechanism, a tunneling mechanism, an acoustic emission mechanism and a data acquisition and control mechanism, the stress loading mechanism comprises a first power assembly and a pressure head assembly, and the pressure head assembly is connected with the first power assembly; the pressure head assembly is used for applying stress to the surface of the rock mass sample along three mutually orthogonal directions of the rock mass sample under the driving of the first power assembly. And the data acquisition and control mechanism is respectively connected with the stress loading mechanism, the tunneling mechanism and the acoustic emission mechanism. The tunneling mechanism and the acoustic emission mechanism are arranged on the pressure head assembly, the interior of a rock mass sample is tunneled while pressure is applied, acoustic emission data of internal damage are collected and calculated in real time, the data collection and control mechanism analyzes the acoustic emission data, the tunneling speed of the tunneling mechanism is dynamically adjusted, and the acoustic emission data of the internal damage are acquired and calculated in real time. Feedback adjustment of the tunneling speed is achieved, and meanwhile the stability of the rock mass sample in the tunneling process is improved.

Description

Technical Field

[0001] This application relates to the field of rock mechanics experimental equipment technology, and in particular to a control system and control method. Background Technology

[0002] Currently, with the increasing demand for deep resource development (such as deep minerals, shale gas, and geothermal energy), major underground engineering construction (such as the Sichuan-Tibet Railway's extra-long tunnels and cross-sea tunnels), and deep geological disposal of nuclear waste, deep underground space engineering is facing severe challenges from extremely complex environments characterized by "high ground stress, high ground temperature, and high permeability." Under these complex conditions, the stress state of the rock mass ahead of the tunneling process can undergo drastic adjustments, easily inducing engineering disasters such as rock bursts, surrounding rock instability, and stuck drill bits, impacting construction safety and efficiency.

[0003] While existing true triaxial loading systems can effectively simulate the mechanical response of rock samples under quasi-static stress, their core component—the indenter—is a solid, rigid block primarily used to transfer uniform boundary stress. This structure lacks any form of mechanical rock breaking or material removal capability. Therefore, current technology can only apply loads to rock samples until they fail as a whole, and cannot simulate the changes in rock sample morphology and the dynamic adjustment of the stress field ahead caused by the continuous advancement of the excavation face during tunnel excavation, drilling, and other tunneling operations.

[0004] Acoustic emission (AE) technology, as a dynamic non-destructive testing technique, can be used to track the evolution of damage within rock samples in real time, identify the spatiotemporal distribution of damage, and provide early warning information for macroscopic failure. However, AE technology can only monitor the damage process of rocks under pure stress loading. In actual engineering, however, the main risk comes from the strong disturbance generated by tunneling tools (such as TBM cutterheads and drill bits) on the rock sample. This disturbance induces new damage zones within the surrounding rock that couple with the original geostress field, which is the core cause of instability phenomena such as rock bursts and spalling. Existing testing techniques cannot simulate the actual tunneling process while applying real triaxial stress, resulting in monitoring systems such as AE being unable to capture the damage response signals inside the rock sample "under tunneling disturbance." Therefore, the monitored data is difficult to reflect the most crucial "tunneling-induced damage evolution" process in engineering practice, ultimately significantly reducing the research value and guidance for practical engineering.

[0005] Meanwhile, in existing technologies, true triaxial loading, acoustic emission monitoring, and drilling devices are independent of each other, making it impossible to achieve dynamic parameter adjustment based on real-time rock damage response (such as acoustic emission signals). Summary of the Invention

[0006] This application aims to at least solve one of the aforementioned technical problems existing in the prior art. Therefore, the purpose of this application is to provide a control system and method that can solve the problem that the prior art cannot achieve dynamic parameter adjustment based on real-time rock damage.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows: A control system, applied to a rock mass sample, includes... A stress loading mechanism includes a first power component and an indenter assembly. The first power component provides power to the indenter assembly, which is connected to the first power component. The indenter assembly applies stress to the surface of the rock mass sample along three mutually orthogonal directions under the drive of the first power component. The tunneling mechanism, mounted on the pressure head assembly, is used for tunneling rock mass samples; Acoustic emission mechanism, used to collect and calculate acoustic emission data generated by internal damage to rock samples during tunneling in real time; The data acquisition and control mechanism is connected to the stress loading mechanism, the tunneling mechanism and the acoustic emission mechanism respectively, and is used to collect and analyze the operating data and calculated data of the stress loading mechanism, the tunneling mechanism and the acoustic emission mechanism, and dynamically adjust the tunneling rate of the tunneling mechanism according to the analysis results.

[0008] According to some embodiments of this application, the pressure head assembly includes a first pressure head component, a second pressure head component, and a third pressure head component arranged in pairs along three mutually orthogonal directions of the rock mass sample. At least one of the second pressure head components is provided with the tunneling mechanism, and the third pressure head component is used for the acoustic emission mechanism to collect acoustic emission data generated by internal damage to the rock mass sample during the tunneling process.

[0009] According to some embodiments of this application, the second pressure head component has a flat first contact surface that abuts against the rock mass sample, the first contact surface being used to apply stress to the surface of the rock mass sample, and the second pressure head component is provided with a tunneling channel for the tunneling mechanism to pass through.

[0010] According to some embodiments of this application, the tunneling mechanism includes a drill rod and a drill bit, the drill bit being connected to the drill rod, and the drill bit being used to tunnel the rock mass sample.

[0011] According to some embodiments of this application, the drill rod is equipped with a displacement sensor and a force sensor, which are connected to the data acquisition and control mechanism to monitor the drilling depth of the drill bit and the pressure it experiences during drilling.

[0012] According to some embodiments of this application, the control system further includes a second power component, which includes a rotary drive component and a feed drive component. The rotary drive component is used to drive the drill rod and drill bit to rotate, and the feed drive component is used to drive the drill rod and drill bit to move along the tunneling direction. The rotary drive component and the feed drive component are respectively connected to the data acquisition and control mechanism.

[0013] According to some embodiments of this application, the third pressure head component has a flat second contact surface that abuts against the rock mass sample, the second contact surface being used to apply stress to the surface of the rock mass sample, and the third pressure head component is provided with mounting holes for mounting part of the acoustic emission mechanism.

[0014] A control method, implemented using the aforementioned control system, includes the following steps: The parameters are set, including: stress loading path, target stress value, initial tunneling rate of the tunneling mechanism, maximum tunneling rate, minimum tunneling rate, and control threshold of the acoustic emission mechanism; The first power unit is activated, causing the pressure head assembly to apply stress to the rock mass sample along the stress loading path and according to the target stress value until the target stress state is reached; The tunneling mechanism is started to tunnel the rock mass sample at the initial tunneling rate. At the same time, the acoustic emission mechanism collects and calculates acoustic emission data in real time, and transmits the calculated acoustic emission data to the data acquisition and control mechanism. The data acquisition and control mechanism performs real-time analysis and judgment on the acoustic emission data calculated in each control cycle, determines the state of the rock mass sample based on the analysis results, and generates corresponding control strategies. The data acquisition and control mechanism adjusts the tunneling rate according to the control strategy, and the tunneling mechanism continues to tunnel according to the adjusted tunneling rate, and enters the next cycle to continuously monitor the acoustic emission signal and adjust the tunneling rate. The acoustic emission data is collected cyclically and the tunneling rate is adjusted in control cycles until the tunneling depth reaches the predetermined depth.

[0015] According to some embodiments of this application, the data acquisition and control mechanism performs real-time analysis and judgment on the acoustic emission data calculated in each control cycle, determines the state of the rock mass sample based on the analysis results, and generates corresponding control strategies, including: The acoustic emission mechanism calculates the number of events based on the acoustic signal data and transmits it to the data acquisition and control mechanism. The data acquisition and control mechanism compares the number of events with the control threshold, determines the tunneling status based on the comparison result, and generates the control strategy.

[0016] According to some embodiments of this application, the control threshold includes a first threshold range, a second threshold range, and a third threshold range, and the control strategy includes the following steps: If the number of acoustic emission events is within the first threshold range, it is determined to be a safe state, and the data acquisition and control mechanism increases the tunneling rate, with the adjusted tunneling rate not exceeding the maximum tunneling rate; If the number of acoustic emission events is within the second threshold range, it is determined to be a critical state, and the data acquisition and control mechanism reduces or controls the tunneling rate to remain unchanged; If the number of acoustic emission events falls within the third threshold range, it is determined to be a dangerous state, and the data acquisition and control mechanism reduces the tunneling rate to the minimum tunneling rate or suspends tunneling.

[0017] The beneficial effects of this application are: The control system of this application provides power to the pressure head assembly through the first power component, enabling the pressure head component to apply stress to the surface of the rock mass sample. At the same time, the pressure head assembly is also equipped with a tunneling mechanism and an acoustic emission mechanism, which can tunnel into the interior of the rock mass sample while applying pressure, and monitor and collect the acoustic emission signals generated by the damage inside the rock mass sample in real time. The acoustic emission signals are analyzed by the data acquisition and control mechanism, and the tunneling rate of the tunneling mechanism is dynamically adjusted according to the analysis results, so as to realize feedback regulation of the tunneling rate, improve the stability of the rock mass sample during tunneling, and reduce the occurrence of engineering disasters.

[0018] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a control system according to this application.

[0020] Figure 2 This is a schematic diagram of the connection between the tunneling mechanism and the second pressure head component. Figure 1 .

[0021] Figure 3 This is a schematic diagram of the connection between the tunneling mechanism and the second pressure head component. Figure 2 .

[0022] Figure 4 This is a schematic diagram showing the connection between the tunneling mechanism and the second power component.

[0023] Figure 5 This is a schematic diagram of the acoustic emission sensor mounted on the third pressure head component.

[0024] Figure 6 This is a schematic diagram of the acoustic emission mechanism.

[0025] Figure 7 This is a flowchart of the regulation method in this application. Figure 8 This is a schematic diagram of the regulation strategy.

[0026] Figure label: 100. First power component; 200. First pressure head component; 210. Fifth pressure section; 220. Sixth pressure section; 300. Second pressure head component; 310. First pressure part; 320. Second pressure part; 321. Second through hole; 400. Third pressure head component; 410. Third pressure section; 420. Fourth pressure section; 410. Mounting hole; 500. Tunneling mechanism; 510. Drill rod; 520. Drill bit; 530. First servo motor; 540. Second servo motor; 550. Torque sensor; 560. Displacement sensor; 600. Acoustic emission mechanism; 610. Acoustic emission sensor; 620. Preamplifier; 630. High-speed data acquisition unit; 640. Acoustic emission monitoring component; 650. Transmission cable; 660. Connector; 700, Data acquisition and control mechanism; 800, Second power assembly; 900, Rock mass sample. Detailed Implementation

[0027] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0028] In the description of this application, it should be understood that if directional descriptions are involved, such as up, down, front, back, left, right, etc., indicating the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0029] In the description of this application, if words such as several, greater than, less than, exceeding, above, below, or within appear, "several" means one or more, "more than" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, and "above," "below," "within," etc. are understood to include the number itself.

[0030] In the description of this application, the use of terms such as "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0031] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0032] Reference Figures 1 to 8 The following are specific embodiments of this application.

[0033] Depend on Figure 1 As shown, this application provides a control system that acts on a rock mass sample 900, including a stress loading mechanism, a tunneling mechanism 500, an acoustic emission mechanism 600, and a data acquisition and control mechanism 700. The stress loading mechanism includes a first power component 100 and a pressure head assembly. The first power component 100 provides power to the pressure head assembly, which is connected to the first power component 100. The pressure head assembly applies stress to the surface of the rock mass sample 900 along three mutually orthogonal directions under the drive of the first power component 100.

[0034] The tunneling mechanism 500 is mounted on the pressure head assembly and is used to tunnel the rock mass sample 900.

[0035] The acoustic emission mechanism 600 is used to collect and calculate acoustic emission data generated by internal damage to the rock sample 900 during the tunneling process in real time.

[0036] The data acquisition and control mechanism 700 is connected to the stress loading mechanism, the tunneling mechanism 500 and the acoustic emission mechanism 600 respectively. It is used to collect and analyze the operating data and calculated data of the stress loading mechanism, the tunneling mechanism 500 and the acoustic emission mechanism 600, and dynamically adjust the tunneling rate of the tunneling mechanism 500 according to the analysis results.

[0037] Furthermore, the first power component 100 is a servo hydraulic system.

[0038] In some embodiments, the indenter assembly includes three mutually orthogonal directions along the rock mass sample 900 (i.e., Figure 1The first pressure head component 200, the second pressure head component 300, and the third pressure head component 400 (shown as X-axis, Y-axis, and Z-axis) are respectively arranged in pairs. Specifically, the first pressure head component 200 is arranged in pairs along the Y-axis direction, the second pressure head component 300 is arranged along the Z-axis direction, and the third pressure head component 400 is arranged in pairs along the X-axis direction. At least one of the second pressure head components 300 is equipped with a tunneling mechanism 500, and the third pressure head component 400 is used for the acoustic emission mechanism 600 to collect acoustic emission data generated by internal damage of the rock mass sample 900 during the tunneling process.

[0039] Depend on Figure 2 and Figure 3 As shown, in some embodiments, the second pressure head component 300 has a flat first contact surface that abuts against the rock mass sample 900. The first contact surface is used to apply stress to the surface of the rock mass sample 900. The second pressure head component 300 is provided with a tunneling channel for the tunneling mechanism 500 to pass through.

[0040] In some embodiments, the second pressure head component 300 includes a first pressure part 310 and a second pressure part 320, the first pressure part 310 and the second pressure part 320 are fixedly connected, the surfaces of the first pressure part 310 and the second pressure part 320 are flat, and are used to apply uniform stress to the surface of the rock mass sample 900, wherein the first contact surface is the surface of the second pressure part 320 on the side close to the rock mass sample 900.

[0041] The first pressing part 310 and the second pressing part 320 are respectively provided with a first through hole (not shown) and a second through hole 321. The first through hole and the second through hole 321 are coaxially arranged to form a tunneling channel for the tunneling mechanism 500 to pass through in order to tunnel the rock sample 900.

[0042] In some embodiments, the tunneling mechanism 500 includes a drill rod 510 and a drill bit 520, the drill bit 520 being connected to the drill rod 510 and used for tunneling the rock mass sample 900.

[0043] Specifically, the drill rod 510 is connected to the drill bit 520 and can pass through the first through hole and the second through hole 321 in sequence. The first through hole and the second through hole 321 are respectively located at the center of the first pressure part 310 and the second pressure part 320.

[0044] In some embodiments, the drill rod 510 is used to transmit power and support the drill bit, and the drill bit 520 is a replaceable drill bit. The drill rod 510 and the drill bit 520 are detachably connected, and different drill bits are selected according to the rock mass sample conditions. Both the drill rod 510 and the drill bit 520 have threaded holes on their surfaces to facilitate chip removal or cooling during the tunneling process, thereby improving tunneling efficiency and stability.

[0045] In some embodiments, the drill rod 510 is provided with a displacement sensor 560 and a force sensor (not shown), which are connected to the data acquisition and control mechanism 700 to monitor the drilling depth of the drill bit 520 and the pressure it experiences during drilling.

[0046] Furthermore, the diameter of the first pressing part 310 is smaller than the diameter of the second pressing part 320, and the cross-sections of both the first pressing part 310 and the second pressing part 320 are square.

[0047] Depend on Figure 4 As shown, in some embodiments, the control system further includes a second power assembly 800. The second power assembly 800 includes a rotary drive component and a feed drive component. The rotary drive component is used to drive the drill rod 510 and the drill bit 520 to rotate, and the feed drive component is used to drive the drill rod 510 and the drill bit 520 to move along the tunneling direction. The rotary drive component and the feed drive component are respectively connected to the data acquisition and control mechanism 700.

[0048] Furthermore, the rotary drive components include a first servo motor 530, a reducer (not shown), a coupling (not shown), and a main shaft (not shown), all mounted on a base (not shown). The output end of the first servo motor 530 is connected to the input end of the reducer, the output end of the reducer is connected to one end of the coupling, the other end of the coupling is connected to one end of the main shaft, and the other end of the main shaft is connected to the drill pipe 510. A torque sensor 550 is provided at the connection between the main shaft and the drill pipe 510, which is used to monitor the torque during the tunneling process in real time. A speed sensor is provided at the output end of the servo motor, which is used to monitor the rotational speed during the tunneling process in real time.

[0049] The feed drive component includes a second servo motor 540 and a ball screw mechanism (not shown). The ball screw mechanism includes a ball screw, a ball nut, and balls. Both the surface of the ball screw and the ball nut are provided with helical raceways, and the balls roll between the helical raceways to achieve motion transmission. The output end of the second servo motor 540 is connected to the ball screw, and the ball nut is connected to the base of the rotary drive component.

[0050] The second power assembly 800 operates as follows: The first servo motor 530 and the second servo motor 540 are started under the control of the data acquisition and control mechanism. The second servo motor 540 drives the ball screw to rotate, which in turn drives the ball nut, along with the entire rotary drive component, to perform a smooth linear motion along the Z-axis. The speed of this linear motion is the tunneling rate. Simultaneously, the first servo motor 530 drives the main shaft to rotate through a reducer and coupling. The main shaft drives the drill rod 510 and drill bit 520 to rotate, thus forming a continuous linear motion of the drill rod 510 and drill bit 520 along the Z-axis while simultaneously rotating, achieving continuous tunneling of the rock sample 900. During tunneling, the torque sensor 550, speed sensor, displacement sensor 560, and force sensor monitor data in real time and transmit it to the data acquisition and control mechanism.

[0051] Depend on Figure 5 and Figure 6 As shown, in some embodiments, the third pressure head component 400 has a flat second contact surface that abuts against the rock mass sample 900. The second contact surface is used to apply stress to the surface of the rock mass sample 900. The third pressure head component 400 is provided with a mounting hole 421 for mounting a portion of the acoustic emission mechanism 600.

[0052] In some embodiments, the third pressure head component 400 includes a third pressure portion 410 and a fourth pressure portion 420, which are fixedly connected and have flat surfaces, for applying uniform stress to the surface of the rock mass sample 900. The second contact surface is the surface of the fourth pressure portion 420 near the rock mass sample 900. At least one mounting hole 421 is provided on the fourth pressure portion 420 for accommodating a portion of the acoustic emission mechanism.

[0053] Furthermore, the fourth pressure section 420 has four mounting holes 421, which are located at the four corners of the fourth pressure section 420. A total of eight acoustic emission sensors 610 form a three-dimensional spatial monitoring array to monitor the acoustic emission signals inside the rock mass sample in all directions in real time.

[0054] Furthermore, the diameter of the third pressing part 410 is smaller than the diameter of the fourth pressing part 420, and the cross-sections of both the third pressing part 410 and the fourth pressing part 420 are square.

[0055] In some embodiments, the acoustic emission mechanism 600 includes an acoustic emission sensor 610, a preamplifier 620, a high-speed acquisition device 630, and an acoustic emission monitoring component 640, as well as a transmission cable 650 connecting each component in series.

[0056] The acoustic emission sensor 610 is installed in the mounting hole 421 and transmits the collected acoustic emission signal to the preamplifier 620 through the transmission cable 650. The preamplifier 620 is used to amplify the acoustic emission signal. The high-speed acquisition instrument 630 is used to convert the acoustic emission signal into a digital waveform. The acoustic emission monitoring component 640 is used to perform real-time analysis of the digital waveform, specifically analyzing various parameters in the acoustic emission, including the number of events, the number of rings, the amplitude, and the energy, and then sending the analyzed data to the data acquisition and control mechanism 700.

[0057] In some embodiments, the acoustic emission mechanism further includes a connector 660, which is disposed on the transmission cable 650 of the preamplifier 620 near the acoustic emission sensor 610. The connector 660 is used to ensure stable transmission of the acoustic emission signal.

[0058] Furthermore, the transmission cable 650 is a coaxial cable, which features low noise performance and a shielding layer to reduce electromagnetic interference. The connector 660 is a BNC connector. The acoustic emission sensor 610 is spring-loaded within the mounting hole 421, ensuring a tight contact between the sensor and the bottom of the hole. This guarantees that the sensor adheres firmly to the surface of the rock sample 900, even during system vibration or minor deformation, ensuring high-quality acoustic signal reception. Moreover, by embedding the acoustic emission sensor 610 within the mounting hole 421, compared to traditional external mounting, it offers advantages such as precise positioning and strong anti-interference capabilities, while also protecting the sensor.

[0059] In some embodiments, the acoustic emission sensor 610 is a piezoelectric ceramic sheet.

[0060] The acoustic emission mechanism operates as follows: When the elastic wave generated by the micro-fracture of the rock sample 900 reaches the acoustic emission sensor 610, the piezoelectric ceramic plate generates a weak voltage signal due to the pressure. The voltage signal generated by the acoustic emission sensor 610 is transmitted to the preamplifier 620 via a coaxial cable. The preamplifier 620 amplifies and filters the voltage signal by 40dB or 60dB to improve the signal-to-noise ratio. The amplified and filtered signal is then input to the high-speed acquisition instrument 630. The high-speed acquisition instrument 630 converts the acoustic emission signal from analog to digital waveform at a sampling rate at the MHz level. The acoustic emission monitoring component 640 performs real-time analysis of the digital waveform and extracts characteristic parameters of the acoustic emission, such as amplitude, energy, number of events, and number of rings, and calculates derived indices, such as the b-value.

[0061] In some embodiments, the first pressure head component 200 includes a fifth pressure part 210 and a sixth pressure part 220, which are fixedly connected and have flat surfaces, for applying uniform stress to the surface of the rock mass sample 900.

[0062] Furthermore, the diameter of the fifth pressing part 210 is smaller than the diameter of the sixth pressing part 220, and the cross-sections of both the fifth pressing part 210 and the sixth pressing part 220 are square.

[0063] Furthermore, the first pressure section 310, the second pressure section 320, the third pressure section 410, the fourth pressure section 420, the fifth pressure section 210, and the sixth pressure section 220 are all solid rigid steel pressure heads, which can prevent unnecessary elastic deformation of the pressure head assembly during stress loading, thereby affecting the accuracy and stability of stress control.

[0064] Depend on Figure 7 As shown, this application also provides a control method, implemented using the above-described control system, comprising the following steps: S100, System Initialization and Parameter Setting: Set parameters in the data acquisition and control mechanism 700. The parameters include: stress loading path, target stress value, initial tunneling rate of tunneling mechanism 500, maximum tunneling rate, minimum tunneling rate, and control threshold of acoustic emission mechanism 600.

[0065] The stress loading path consists of three mutually orthogonal directions, namely... Figure 1 The X, Y, and Z axes are shown in the diagram. The target stress values ​​are: σ1 on the Y-axis, σ2 on the X-axis, and σ3 on the Z-axis.

[0066] The stress values ​​of σ1, σ2, and σ3 can be the same or different. When the size of the rock sample is 100mm*100mm*100mm, the maximum loading force in the three directions is 3000Kn, and the corresponding maximum stress in the three directions is 300MPa.

[0067] The initial tunneling rate of the tunneling mechanism 500 is 4.5 mm / min, and the range of the tunneling rate is 0.01 mm / min to 10 mm / min, that is, the minimum tunneling rate is V. min The value is 0.1 mm / min, and the maximum tunneling rate is V. max The value is 10 mm / min.

[0068] S200, Apply the target stress value to the surface of the rock mass sample: Start the first power component 100 to apply stress to the rock mass sample along the stress loading path and according to the target stress value to the target stress state.

[0069] The target stress state is a preset true triaxial stress state, where σ1, σ2 and σ3 are independent and controllable. The stress state is kept stable during the tunneling process to simulate the complex stress environment experienced by real rock samples.

[0070] S300, tunneling mechanism 500 starts and acoustic emission mechanism 600 monitors in real time: tunneling mechanism 500 starts and tunnels rock mass sample 900 at the initial tunneling rate. At the same time, acoustic emission mechanism 600 collects acoustic emission signals in real time and calculates acoustic emission data, and transmits the calculated acoustic emission data to data acquisition and control mechanism 700.

[0071] S400 and the data acquisition and control mechanism 700 analyze acoustic emission data in real time and determine the tunneling status, and generate control strategies: The data acquisition and control mechanism 700 performs real-time analysis and judgment on the acoustic emission data collected in each control cycle, determines the rock mass sample status based on the analysis results, and generates corresponding control strategies.

[0072] S500 and the data acquisition and control mechanism 700 send control strategies to each device, and each device executes the control strategies: the data acquisition and control mechanism 700 adjusts the tunneling rate according to the control strategies, and the tunneling mechanism 500 continues to tunnel according to the adjusted tunneling rate, and enters the next cycle to continuously monitor the acoustic emission signal and adjust the tunneling rate.

[0073] Specifically, the data acquisition and control mechanism 700 sends the adjusted tunneling rate as an instruction to the first servo motor 530 and the second servo motor 540, and the first servo motor 530 and the second servo motor 540 adjust their respective speeds to match the new rate.

[0074] S600: Continuous monitoring until the tunneling reaches the predetermined depth, tunneling and monitoring stop simultaneously: The acoustic emission signal is monitored cyclically and the tunneling rate is adjusted in control cycles until the tunneling depth reaches the predetermined depth, at which point tunneling and acoustic emission monitoring stop simultaneously.

[0075] Furthermore, all data throughout the process is given a unified timestamp and fully recorded for subsequent in-depth analysis.

[0076] In some embodiments, a control cycle is defined as every 100 milliseconds.

[0077] In some embodiments, the acoustic emission monitoring component 640 calculates the number of events to form acoustic emission data and compares the acoustic emission data with a control threshold, the number of events being used to generate a control strategy.

[0078] Furthermore, the Gutenberg-Richard law is used to calculate the b-value, which ranges from 0.65 to 2.9. A significant decrease in the b-value is a precursor to macroscopic fracturing of the rock sample at 900°C. In this application, the number of acoustic emission events and the b-value are used to determine the tunneling status.

[0079] The control thresholds include a first threshold range, a second threshold range, and a third threshold range, which are determined by... Figure 8 As shown, the control strategy includes the following steps: If the number of acoustic emission events is within the first threshold range, it is determined to be a safe state. The data acquisition and control mechanism 700 increases the tunneling rate, and the adjusted tunneling rate does not exceed the maximum tunneling rate. If the number of acoustic emission events is within the second threshold range, it is determined to be a critical state, and the data acquisition and control mechanism 700 reduces or controls the tunneling rate to remain unchanged; If the number of acoustic emission events falls within the third threshold range, it is determined to be a dangerous state, and the data acquisition and control mechanism 700 reduces the tunneling rate to the minimum tunneling rate or suspends tunneling.

[0080] In some embodiments, the first threshold range is when the number of acoustic emission events is less than or equal to 60 events / s, or the b value is greater than or equal to 1.

[0081] Specifically, if the number of acoustic emission events is less than or equal to 60 events / s, or the b-value is greater than or equal to 1, it indicates that the internal damage activity level of the rock mass sample 900 is low, the internal state of the rock mass sample is stable, and it is judged to be in a safe state. The data acquisition and control mechanism 700 increases the tunneling rate. The adjusted tunneling rate can be 1.05 times the current tunneling rate, but the adjusted tunneling rate must not exceed the maximum tunneling rate V. max By increasing the tunneling rate, tunneling efficiency can be improved.

[0082] The second threshold range is when the number of acoustic emission events is between 60 events / s and 100 events / s, or when the b value is less than 1.

[0083] Specifically, if the number of acoustic emission events is between 60 events / s and 100 events / s, or if the b value is less than 1, it indicates that the internal damage of the rock mass sample 900 has begun to intensify, and it enters a warning state, which is judged as a critical state. The data acquisition and control mechanism 700 reduces or controls the tunneling rate to remain unchanged in order to stabilize the tunneling process.

[0084] Furthermore, the data acquisition and control mechanism 700 reduces the tunneling rate, and the adjusted tunneling rate can be 0.95 times the current tunneling rate.

[0085] The third threshold range is when the number of rings and events of acoustic emission exceeds 100 events / s, or the b value is less than 0.65.

[0086] Specifically, if the number of acoustic emission events exceeds 100 events / s, or the b-value is less than 0.65, it indicates severe internal damage to the rock mass sample 900, posing a high risk of instability or rockburst, and is therefore classified as a dangerous state. The data acquisition and control mechanism 700 adjusts the tunneling rate to the minimum tunneling rate V. min Or suspend tunneling and issue an alarm signal.

[0087] in Figure 8 In this context, AE monitoring refers to acoustic emission (AE) monitoring.

[0088] The control system and control method in this application can be applied to experiments simulating the mechanical tunneling process (such as tunnel boring machine TBM, drilling, etc.) of deep rock samples under real triaxial stress in a laboratory environment.

[0089] This application discloses a control system and method that provides power to a pressure head assembly via a first power component, enabling the pressure head to apply stress to the surface of a rock mass sample. The pressure head assembly also includes a tunneling mechanism and an acoustic emission mechanism, allowing for tunneling within the rock mass sample while applying pressure. This enables real-time acquisition and calculation of acoustic emission data generated by internal damage within the rock mass sample. The acoustic emission data is analyzed by a data acquisition and control mechanism, and the tunneling rate of the tunneling mechanism is dynamically adjusted based on the analysis results, achieving feedback regulation of the tunneling rate. Furthermore, this application integrates stress loading, tunneling, monitoring, and control, enabling the reproduction of the dynamic coupling effect between the stress environment and mechanical rock-breaking disturbance—two key factors—in a laboratory setting. This allows the research results to provide guidance for predicting and preventing tunneling-induced rock mass sample instability.

[0090] In the description of this specification, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0091] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A control system, characterized in that, Acting on rock mass samples, including A stress loading mechanism includes a first power component and an indenter assembly. The first power component provides power to the indenter assembly, which is connected to the first power component. The indenter assembly applies stress to the surface of the rock mass sample along three mutually orthogonal directions under the drive of the first power component. The tunneling mechanism, mounted on the pressure head assembly, is used for tunneling rock mass samples; Acoustic emission mechanism, used to collect and calculate acoustic emission data generated by internal damage to rock samples during tunneling in real time; The data acquisition and control mechanism is connected to the stress loading mechanism, the tunneling mechanism and the acoustic emission mechanism respectively, and is used to collect and analyze the operating data and calculated data of the stress loading mechanism, the tunneling mechanism and the acoustic emission mechanism, and dynamically adjust the tunneling rate of the tunneling mechanism according to the analysis results.

2. The control system according to claim 1, characterized in that, The pressure head assembly includes a first pressure head component, a second pressure head component, and a third pressure head component arranged in pairs along three mutually orthogonal directions of the rock mass sample. At least one of the second pressure head components is equipped with the tunneling mechanism. The third pressure head component is used for the acoustic emission mechanism to collect acoustic emission data generated by internal damage to the rock mass sample during the tunneling process.

3. The control system according to claim 2, characterized in that, The second pressure head component has a flat first contact surface that abuts against the rock mass sample. The first contact surface is used to apply stress to the surface of the rock mass sample. The second pressure head component is provided with a tunneling channel for the tunneling mechanism to pass through.

4. The control system according to claim 3, characterized in that, The tunneling mechanism includes a drill rod and a drill bit, the drill bit being connected to the drill rod and used to tunnel the rock sample.

5. The control system according to claim 4, characterized in that, The drill rod is equipped with a displacement sensor and a force sensor, which are connected to the data acquisition and control mechanism to monitor the drilling depth of the drill bit and the pressure it experiences during drilling.

6. The control system according to claim 5, characterized in that, The control system further includes a second power component, which includes a rotary drive component and a feed drive component. The rotary drive component is used to drive the drill rod and drill bit to rotate, and the feed drive component is used to drive the drill rod and drill bit to move along the tunneling direction. The rotary drive component and the feed drive component are respectively connected to the data acquisition and control mechanism.

7. The control system according to claim 2, characterized in that, The third pressure head component has a flat second contact surface that abuts against the rock mass sample. The second contact surface is used to apply stress to the surface of the rock mass sample. The third pressure head component is provided with mounting holes for installing part of the acoustic emission mechanism.

8. A control method, characterized in that, The control system according to any one of claims 1-7 is used to achieve the following steps: The parameters are set, including: stress loading path, target stress value, initial tunneling rate of the tunneling mechanism, maximum tunneling rate, minimum tunneling rate, and control threshold of the acoustic emission mechanism; The first power unit is activated, causing the pressure head assembly to apply stress to the rock mass sample along the stress loading path and according to the target stress value until the target stress state is reached; The tunneling mechanism is started to tunnel the rock mass sample at the initial tunneling rate. At the same time, the acoustic emission mechanism collects and calculates acoustic emission data in real time, and transmits the calculated acoustic emission data to the data acquisition and control mechanism. The data acquisition and control mechanism performs real-time analysis and judgment on the acoustic emission data calculated in each control cycle, determines the state of the rock mass sample based on the analysis results, and generates corresponding control strategies. The data acquisition and control mechanism adjusts the tunneling rate according to the control strategy, and the tunneling mechanism continues to tunnel according to the adjusted tunneling rate, and enters the next cycle to continuously acquire acoustic emission data and adjust the tunneling rate. The acoustic emission data is collected cyclically and the tunneling rate is adjusted in control cycles until the tunneling depth reaches the predetermined depth.

9. The control method according to claim 8, characterized in that, The data acquisition and control mechanism performs real-time analysis and judgment on the acoustic emission data calculated in each control cycle, determines the state of the rock mass sample based on the analysis results, and generates corresponding control strategies, including: The acoustic emission mechanism calculates the number of events based on the acoustic signal data and transmits it to the data acquisition and control mechanism. The data acquisition and control mechanism compares the number of events with the control threshold, determines the tunneling status based on the comparison result, and generates the control strategy.

10. The control method according to claim 9, characterized in that, The control threshold includes a first threshold range, a second threshold range, and a third threshold range, and the control strategy includes the following steps: If the number of acoustic emission events is within the first threshold range, it is determined to be a safe state, and the data acquisition and control mechanism increases the tunneling rate, with the adjusted tunneling rate not exceeding the maximum tunneling rate; If the number of acoustic emission events is within the second threshold range, it is determined to be a critical state, and the data acquisition and control mechanism reduces or controls the tunneling rate to remain unchanged; If the number of acoustic emission events falls within the third threshold range, it is determined to be a dangerous state, and the data acquisition and control mechanism reduces the tunneling rate to the minimum tunneling rate or suspends tunneling.

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