Anchor rod active prestress release system for deep surrounding rock stability control

Abstract

The invention relates to the technical field of underground engineering support, and discloses an anchor rod active prestress releasing system for deep surrounding rock stability control, which comprises an anchor rod body, a prestress applying assembly, a surrounding rock state monitoring assembly, a prestress executing and releasing assembly and a central control unit. One end of the anchor rod body is anchored to the bottom of a deep surrounding rock preset drill hole, and the other end of the anchor rod body extends out of the drill hole. The prestress applying assembly is arranged at the end, extending out of the drill hole, of the anchor rod body in a sleeving mode and used for applying initial prestress to the anchor rod body. Surrounding rock stress and displacement data are collected in real time through the surrounding rock state monitoring assembly, the central control unit automatically judges and drives the prestress executing and releasing assembly to act according to a preset threshold value, and the limitation that a traditional anchor rod cannot be adjusted according to dynamic changes of surrounding rock after prestress is applied is broken through. And stress redistribution generated by excavation disturbance of the deep surrounding rock can be adapted in time.

Description

Technical Field

[0001] This invention relates to the field of underground engineering support technology, specifically to an active prestress release system for anchor bolts used for stability control of deep surrounding rock. Background Technology

[0002] In engineering fields such as deep mining of mineral resources and construction of deep-buried tunnels, the surrounding rock in deep areas is subject to high initial ground stress. After excavation and disturbance, stress redistribution is likely to occur, accompanied by instability risks such as deformation, crack propagation, and even collapse. Therefore, the stability control of the surrounding rock has become a core requirement for ensuring the safety of the project. At present, the mainstream control method in the industry is anchor bolt support technology. It applies prestress to the anchor bolt body and uses the anchoring effect between the anchor bolt and the surrounding rock to constrain the deformation of the surrounding rock. Among them, active prestressed anchor bolts have a greater advantage in stability control than traditional passive anchor bolts because they can apply prestress in advance and actively inhibit early deformation of the surrounding rock. They have gradually replaced passive anchor bolts as the main support form for deep engineering.

[0003] However, existing active prestressed anchor technology still has significant limitations: First, the prestress of existing active prestressed anchors is mostly set and applied once during the construction phase, and cannot be adjusted according to the dynamic changes of the surrounding rock. Deep surrounding rock undergoes continuous changes in stress state and deformation characteristics during engineering progress due to factors such as excavation unloading, lithological differences, and time effects. A fixed prestress is prone to two problems: when the surrounding rock stress continues to rise, the fixed prestress may fail to release, leading to overload and breakage of the anchor rod, thus losing its support function; when the deformation of the surrounding rock exceeds the prestress constraint range, the fixed prestress is insufficient to effectively inhibit further deformation, ultimately causing instability. Second, while some existing technologies attempt to adjust the prestress manually, such as by using a torque wrench to tighten or loosen the nut, manual adjustment requires workers to enter deep, dangerous work areas. This not only results in slow response times and an inability to respond in real time to sudden deformations of the surrounding rock, but also relies entirely on manual experience and judgment, lacking precise control criteria. This can easily lead to over- or under-release of prestress, which in turn exacerbates the risk to the stability of the surrounding rock. Furthermore, the few existing anchor bolt systems with monitoring functions can only collect and display data on surrounding rock stress and displacement. The monitoring data and the prestress adjustment process are independent of each other, requiring manual intervention to complete data analysis and control operations. This results in control lag and makes it difficult to meet the real-time, accurate, and safe requirements for stability control in the dynamic, complex, and high-risk environment of deep surrounding rock. Therefore, developing an active control system that can automatically and accurately adjust the anchor bolt prestress based on the real-time state of the surrounding rock and has a safety protection mechanism has become a key direction for solving the current problem of stability control in deep surrounding rock. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an active prestress release system for anchor bolts used for stability control in deep surrounding rock, thus solving the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an active prestress release system for anchor bolts for deep surrounding rock stability control, comprising an anchor bolt body, a prestress application component, a surrounding rock condition monitoring component, a prestress release execution component, and a central control unit; One end of the anchor rod is anchored to the bottom of a pre-drilled hole in the deep surrounding rock, and the other end extends to the outside of the hole; the prestressing application component is sleeved on the end of the anchor rod that extends to the outside of the hole, and is used to apply initial prestress to the anchor rod. The surrounding rock condition monitoring component is installed inside the surrounding rock around the anchor rod body and on the borehole wall to collect stress values ​​and displacement data of the surrounding rock. The prestress release assembly is connected in series between the anchor rod body and the prestress application assembly, and is electrically connected to the central control unit; The central control unit receives data transmitted by the surrounding rock condition monitoring component. When the monitored surrounding rock stress value exceeds the preset stress threshold or the surrounding rock displacement exceeds the preset displacement threshold, the central control unit sends a control signal to the prestress release component to drive the prestress release component to release the prestress quantitatively. The released prestress value is adjusted by the preset parameters of the central control unit.

[0006] Preferably, the surrounding rock condition monitoring component includes a stress sensor and a displacement sensor; the stress sensor is embedded in the surrounding rock around the anchor rod body, and at least two are spaced apart along the borehole depth direction to collect surrounding rock stress data at different depths; the displacement sensor is installed between the borehole wall and the anchor rod body, and at least two are spaced apart along the axial direction of the anchor rod body to collect displacement data of the surrounding rock relative to the anchor rod body at different axial positions; both the stress sensor and the displacement sensor are electrically connected to the central control unit through a data transmission line, and the data transmission line is wrapped with a corrosion-resistant and wear-resistant sleeve.

[0007] Preferably, the prestress release assembly includes a drive module, a transmission module, and a locking module. The drive module includes a hydraulic cylinder and an electromagnetic actuator. The cylinder body of the hydraulic cylinder is fixedly connected to the prestress application assembly, and the piston rod of the hydraulic cylinder is connected to the locking module through the transmission module. The electromagnetic actuator is electrically connected to a central control unit to control the oil circuit opening and closing and the oil volume of the hydraulic cylinder. The transmission module is a gear transmission mechanism, including a driving gear and a driven gear. The driving gear is fixedly connected to the piston rod of the hydraulic cylinder, and the driven gear is connected to the locking module. The locking module is sleeved on the outside of the anchor rod body, and its inner wall is provided with an internal thread that matches the external thread of the anchor rod body. When the driven gear rotates, it drives the locking module to move axially along the anchor rod body, thereby realizing the prestress release.

[0008] Preferably, the central control unit includes a data processing module, a threshold comparison module, a control command generation module, and a parameter storage module. The data processing module receives raw data transmitted from the surrounding rock condition monitoring component, filters and reduces noise in the data, and then transmits it to the threshold comparison module. The threshold comparison module compares the processed data with preset stress thresholds and displacement thresholds in the parameter storage module. When the data exceeds the corresponding threshold, a trigger signal is sent to the control command generation module. The control command generation module generates a prestress release control command based on the trigger signal and preset release parameters in the parameter storage module and sends it to the prestress release execution component. The parameter storage module can modify and update the threshold parameters and release parameters through an external terminal.

[0009] Preferably, the prestressing application assembly includes a preload nut, a washer, and a preload drive; the preload nut is threadedly connected to one end of the anchor rod extending outside the borehole, and the washer is disposed between the preload nut and the prestressing release assembly; the preload drive is a torque wrench, the output end of which engages with the preload nut to apply a set torque to the preload nut, so that the anchor rod receives initial prestress; a torque sensor is disposed on the outside of the preload nut, and the torque sensor is electrically connected to the central control unit to monitor the torque value of the preload nut in real time and feed it back to the central control unit.

[0010] Preferably, it also includes a safety protection component, which includes a pressure relay and a displacement limit switch. The pressure relay is installed in the hydraulic circuit of the prestress release component and is electrically connected to the central control unit. When the hydraulic circuit pressure exceeds the preset safety pressure, the pressure relay sends a stop signal to the central control unit. The displacement limit switch is installed at the end of the anchor rod extending to the outside of the borehole and is electrically connected to the central control unit. When the locking module of the prestress release component moves to the position of the displacement limit switch, the displacement limit switch sends a stop signal to the central control unit to prevent excessive release of prestress.

[0011] Preferably, the prestress release assembly further includes a displacement encoder, which is installed on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time, convert the angle data into axial displacement data of the locking module, and feed it back to the central control unit to realize closed-loop control of the prestress release amount.

[0012] Preferably, the prestress release assembly further includes a displacement encoder, which is installed on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time, convert the angle data into axial displacement data of the locking module, and feed it back to the central control unit to realize closed-loop control of the prestress release amount.

[0013] Preferably, the prestressing application component further includes an accumulator, which is connected to the hydraulic cylinder of the prestressing release component and is used to store the pressure energy of the hydraulic oil. After the prestressing release component completes one prestressing release, the accumulator replenishes the hydraulic cylinder with hydraulic oil to provide power for the next prestressing release, reducing the need for continuous power supply from the external hydraulic source.

[0014] This invention provides an active prestress release system for anchor bolts used for stability control in deep surrounding rock. It offers the following advantages: 1. This invention collects real-time stress and displacement data of the surrounding rock through a surrounding rock condition monitoring component. The central control unit automatically judges and drives the prestress release component to act according to a preset threshold. This breaks the limitation of traditional anchor bolts, which cannot be adjusted according to the dynamic changes of the surrounding rock after the prestress is applied. It can adapt to the stress redistribution caused by excavation disturbance in deep surrounding rock in a timely manner, and effectively avoids the problem of anchor bolts being pulled apart due to excessive prestress or the surrounding rock becoming unstable due to insufficient prestress.

[0015] 2. This invention constructs a closed-loop control system and multiple safety protection mechanisms throughout the entire process. The prestress release component, combined with a displacement encoder, enables real-time feedback and closed-loop adjustment of the release amount. Meanwhile, the safety protection components limit excessive release from both hydraulic pressure and mechanical displacement perspectives through pressure relays and displacement limit switches. Combined with the torque sensor in the prestress application component monitoring the initial prestress, a complete safety control chain is formed from prestress application and status monitoring to release regulation, significantly reducing the risk of system malfunctions and ensuring reliable operation in deep and complex geological environments.

[0016] 3. This invention reduces the need for continuous power supply from external hydraulic sources by combining an accumulator with a hydraulic cylinder, thereby reducing the complexity of on-site equipment layout and energy consumption. At the same time, it enables real-time data interaction and remote control with ground monitoring terminals through a wireless communication module. This allows staff to monitor the surrounding rock conditions and system operation without frequently entering deep and dangerous work areas, improving on-site safety and facilitating centralized management of multiple systems, making it suitable for large-scale deep engineering applications. Attached Figure Description

[0017] Figure 1 This is the overall flowchart of the present invention; Figure 2 This is a flowchart illustrating the safety protection process of the present invention. Detailed Implementation

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see the appendix Figure 1 - Appendix Figure 2 This invention provides an active prestress release system for anchor bolts used for stability control in deep surrounding rock, comprising an anchor bolt body, a prestress application component, a surrounding rock condition monitoring component, a prestress release execution component, and a central control unit; One end of the anchor rod is anchored to the bottom of a pre-drilled hole in the deep surrounding rock, and the other end extends to the outside of the hole; the prestressing application component is sleeved on the end of the anchor rod that extends to the outside of the hole, and is used to apply initial prestress to the anchor rod. The surrounding rock condition monitoring component is installed inside the surrounding rock around the anchor rod and on the borehole wall to collect stress and displacement data of the surrounding rock. The surrounding rock condition monitoring component includes stress sensors and displacement sensors. The stress sensors are embedded inside the surrounding rock around the anchor rod, with at least two spaced at intervals along the borehole depth direction, to collect stress data of the surrounding rock at different depths. The displacement sensors are installed between the borehole wall and the anchor rod, with at least two spaced at intervals along the axial direction of the anchor rod, to collect displacement data of the surrounding rock relative to the anchor rod at different axial positions. Both the stress sensors and displacement sensors are electrically connected to the central control unit via data transmission lines, and the data transmission lines are wrapped with corrosion-resistant and wear-resistant sleeves.

[0020] Specifically, the anchor rod body is constructed by anchoring one end to the bottom of a pre-drilled hole in the deep surrounding rock and extending the other end to the outside, forming the core carrier for the transmission of support force and providing basic support for the application of prestress and the constraint of the surrounding rock. The prestressing application component is sleeved on the extended end of the rod body. Its core function is to apply initial prestress to the rod body, so that the rod body generates axial tension in advance and transmits it to the surrounding rock, thereby constraining the early deformation of the surrounding rock after excavation and laying the foundation for the initial stress state of active support. The surrounding rock condition monitoring component achieves comprehensive perception of the surrounding rock dynamics through dual-dimensional monitoring of "stress + displacement". The stress sensor is embedded in the surrounding rock at intervals along the borehole depth, which can simultaneously capture the stress change differences of the surrounding rock at different depths, avoiding the stress distribution judgment deviation caused by single-point monitoring. The displacement sensor is installed at intervals between the borehole wall and the rod along the axial direction of the rod, which can accurately obtain the displacement trend of the surrounding rock relative to the anchor at different axial positions and locate the deformation concentration area. The two are connected to the central control unit through a data transmission line wrapped with an anti-corrosion and wear-resistant sleeve, which not only ensures the stability of data transmission in the harsh environment of deep, but also synchronizes the real-time status data of the surrounding rock to the control unit. This provides key status information for subsequent judgment on whether prestress needs to be released and precise control of the release amount, forming a preliminary collaborative working mechanism of "support carrier - initial constraint - status perception".

[0021] The prestress release assembly is connected in series between the anchor rod and the prestressing application assembly, and is electrically connected to the central control unit. The prestress release assembly includes a drive module, a transmission module, and a locking module. The drive module includes a hydraulic cylinder and an electromagnetic actuator. The cylinder body of the hydraulic cylinder is fixedly connected to the prestressing application assembly, and the piston rod of the hydraulic cylinder is connected to the locking module through the transmission module. The electromagnetic actuator is electrically connected to the central control unit and is used to control the oil circuit opening and closing and the oil volume of the hydraulic cylinder. The transmission module is a gear transmission mechanism, including a driving gear and a driven gear. The driving gear is fixedly connected to the piston rod of the hydraulic cylinder, and the driven gear is connected to the locking module. The locking module is sleeved on the outside of the anchor rod, and its inner wall is provided with an internal thread that matches the external thread of the anchor rod. When the driven gear rotates, it drives the locking module to move axially along the anchor rod, thereby releasing the prestress.

[0022] Specifically, the prestress release assembly is connected in series between the anchor rod and the prestressing application assembly. It is the core execution structure that receives commands from the central control unit and achieves precise control of prestress. In its drive module, after receiving the signal from the central control unit, the electromagnetic driver controls the oil circuit opening and closing and the oil quantity of the hydraulic cylinder to output linear driving force. The gear mechanism of the transmission module converts this linear motion into the rotational motion of the driven gear. The locking module moves along the axial direction of the rod under the drive of the driven gear by the thread matching the inner wall with the anchor rod, thereby adjusting the axial tension of the rod and finally realizing the quantitative release of prestress. The cooperation of each module makes the prestress release process controllable and adjustable, accurately responding to the control commands issued by the central control unit based on the surrounding rock condition, and avoiding excessive or insufficient prestress release.

[0023] The central control unit receives data transmitted from the surrounding rock condition monitoring component. When the monitored surrounding rock stress value exceeds a preset stress threshold, or the surrounding rock displacement exceeds a preset displacement threshold, the central control unit sends a control signal to the prestress release component, driving it to release the prestress quantitatively. The released prestress value is adjusted by preset parameters of the central control unit. The central control unit includes a data processing module, a threshold comparison module, a control command generation module, and a parameter storage module. The data processing module receives the raw data transmitted from the surrounding rock condition monitoring component, filters and reduces noise, and then transmits the data to the threshold comparison module. The threshold comparison module compares the processed data with the preset stress and displacement thresholds in the parameter storage module. When the data exceeds the corresponding threshold, a trigger signal is sent to the control command generation module. The control command generation module generates a prestress release control command based on the trigger signal and the preset release parameters in the parameter storage module and sends it to the prestress release component. The parameter storage module can modify and update the threshold parameters and release parameters through an external terminal.

[0024] The prestressing application assembly includes a preload nut, a washer, and a preload drive. The preload nut is threaded to one end of the anchor rod extending outside the borehole. The washer is positioned between the preload nut and the prestressing release assembly. The preload drive is a torque wrench, the output end of which engages with the preload nut to apply a set torque to the preload nut, thereby giving the anchor rod initial prestress. A torque sensor is installed on the outside of the preload nut and is electrically connected to the central control unit to monitor the torque value of the preload nut in real time and feed it back to the central control unit.

[0025] It also includes safety protection components, including a pressure relay and a displacement limit switch. The pressure relay is installed in the hydraulic circuit of the prestress release component and is electrically connected to the central control unit. When the pressure in the hydraulic circuit exceeds the preset safety pressure, the pressure relay sends a stop signal to the central control unit. The displacement limit switch is installed at the end of the anchor rod that extends to the outside of the borehole and is electrically connected to the central control unit. When the locking module of the prestress release component moves to the position of the displacement limit switch, the displacement limit switch sends a stop signal to the central control unit to prevent excessive release of prestress.

[0026] Specifically, the data processing module filters and reduces noise in the raw data transmitted by the surrounding rock condition monitoring component to ensure data validity. Then, the threshold comparison module compares the processed data with preset stress and displacement thresholds in the parameter storage module. If the data exceeds the limits, the control command generation module is triggered, generating a control command based on preset release parameters and sending it to the prestressing release component. Simultaneously, the parameter storage module supports modification of threshold and release parameters via an external terminal, adapting to different deep surrounding rock conditions. The prestressing application component applies a set torque to the prestressing nut through a pre-tightening drive, giving the anchor rod initial support prestress. Washers disperse the pressure between the prestressing nut and the prestressing release component. The torque sensor on the outside of the prestressing nut can monitor the torque value in real time and feed it back to the central control unit, allowing the central control unit to accurately grasp the initial prestressing application state and form a closed loop for monitoring the initial force. The safety protection components serve as the system's last resort. The pressure relay monitors the pressure of the hydraulic oil circuit of the prestressing release component and sends a stop signal to the central control unit when the pressure exceeds the preset safety value to avoid hydraulic system overload. The displacement limit switch sends a stop signal when the locking module moves to the limited position to prevent excessive prestressing release. The three components work together to achieve full-process control from initial prestressing application, dynamic monitoring and control to safety protection, ensuring stable operation of the system in deep and complex environments.

[0027] The prestress release assembly also includes a displacement encoder, which is mounted on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time and convert the angle data into axial displacement data of the locking module, which is then fed back to the central control unit to realize closed-loop control of the prestress release amount.

[0028] The prestress release assembly also includes a displacement encoder, which is mounted on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time and convert the angle data into axial displacement data of the locking module, which is then fed back to the central control unit to realize closed-loop control of the prestress release amount.

[0029] Specifically, the displacement encoder, installed on the driven gear shaft of the transmission module, can capture the rotation angle of the driven gear in real time. Since the driven gear is directly connected to the locking module, its rotation angle can accurately correspond to the axial displacement of the locking module along the anchor rod. The displacement encoder converts this angle data into intuitive displacement data and feeds it back to the central control unit, enabling the central control unit to monitor the actual release progress of the prestressing release component in real time. Then, it compares the actual release amount with the preset release amount and adjusts the control signal sent to the prestressing release component in a timely manner, ultimately achieving precise closed-loop control of the prestressing release amount and avoiding the impact of release deviation on the surrounding rock stability control effect.

[0030] The prestressing application component also includes an accumulator, which is connected to the hydraulic cylinder of the prestressing release component to store the pressure energy of the hydraulic oil. After the prestressing release component completes one prestressing release, the accumulator replenishes the hydraulic cylinder with hydraulic oil to provide power for the next prestressing release, reducing the need for continuous power supply from the external hydraulic source.

[0031] Specifically, the accumulator is connected to the hydraulic cylinder of the prestress release component, and can pre-store the pressure energy of the hydraulic oil. When the prestress release component completes one prestress release and the hydraulic oil pressure in the hydraulic cylinder drops, the accumulator can quickly replenish the hydraulic oil in the hydraulic cylinder and restore the oil circuit pressure, thus reserving power for the next prestress release. This instant replenishment mechanism of pressure energy does not require continuous output of energy from an external hydraulic source, which not only ensures the response speed of the hydraulic drive, but also reduces the dependence on the external power supply system, simplifies the layout of on-site equipment, and reduces energy consumption.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An active prestress release system for anchor bolts used for stability control in deep surrounding rock, characterized in that, It includes the anchor rod body, prestressing application assembly, surrounding rock condition monitoring assembly, prestressing release assembly, and central control unit; One end of the anchor rod is anchored to the bottom of a pre-drilled hole in the deep surrounding rock, and the other end extends to the outside of the hole; the prestressing application component is sleeved on the end of the anchor rod that extends to the outside of the hole, and is used to apply initial prestress to the anchor rod. The surrounding rock condition monitoring component is installed inside the surrounding rock around the anchor rod body and on the borehole wall to collect stress values ​​and displacement data of the surrounding rock. The prestress release assembly is connected in series between the anchor rod body and the prestress application assembly, and is electrically connected to the central control unit; The central control unit receives data transmitted by the surrounding rock condition monitoring component. When the monitored surrounding rock stress value exceeds the preset stress threshold or the surrounding rock displacement exceeds the preset displacement threshold, the central control unit sends a control signal to the prestress release component to drive the prestress release component to release the prestress quantitatively. The released prestress value is adjusted by the preset parameters of the central control unit.

2. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The surrounding rock condition monitoring component includes a stress sensor and a displacement sensor. The stress sensor is embedded in the surrounding rock around the anchor rod body, with at least two sensors spaced at intervals along the borehole depth direction, for collecting stress data of the surrounding rock at different depths. The displacement sensor is installed between the borehole wall and the anchor rod body, with at least two sensors spaced at intervals along the axial direction of the anchor rod body, for collecting displacement data of the surrounding rock relative to the anchor rod body at different axial positions. Both the stress sensor and the displacement sensor are electrically connected to the central control unit via a data transmission line, and the data transmission line is wrapped with a corrosion-resistant and wear-resistant sleeve.

3. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The prestress release assembly includes a drive module, a transmission module, and a locking module. The drive module includes a hydraulic cylinder and an electromagnetic actuator. The cylinder body of the hydraulic cylinder is fixedly connected to the prestress application assembly, and the piston rod of the hydraulic cylinder is connected to the locking module through the transmission module. The electromagnetic actuator is electrically connected to the central control unit and is used to control the oil circuit opening and closing and the oil volume of the hydraulic cylinder. The transmission module is a gear transmission mechanism, including a driving gear and a driven gear. The driving gear is fixedly connected to the piston rod of the hydraulic cylinder, and the driven gear is connected to the locking module. The locking module is sleeved on the outside of the anchor rod body, and its inner wall is provided with an internal thread that matches the external thread of the anchor rod body. When the driven gear rotates, it drives the locking module to move axially along the anchor rod body, thereby realizing the prestress release.

4. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The central control unit includes a data processing module, a threshold comparison module, a control command generation module, and a parameter storage module; the data processing module receives raw data transmitted by the surrounding rock condition monitoring component, filters and reduces noise in the data, and then transmits it to the threshold comparison module. The threshold comparison module compares the processed data with the preset stress threshold and displacement threshold in the parameter storage module. When the data exceeds the corresponding threshold, a trigger signal is sent to the control command generation module. The control command generation module generates a prestress release control command based on the trigger signal and the preset release amount parameter in the parameter storage module and sends it to the prestress release execution component. The parameter storage module can modify and update the threshold parameter and release amount parameter through an external terminal.

5. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The prestressing application assembly includes a preload nut, a washer, and a preload drive component. The preload nut is threadedly connected to one end of the anchor rod extending outside the borehole. The washer is positioned between the preload nut and the prestressing release assembly. The preload drive component is a torque wrench, the output end of which engages with the preload nut to apply a set torque to the preload nut, thereby giving the anchor rod initial prestress. A torque sensor is installed on the outside of the preload nut, and the torque sensor is electrically connected to the central control unit to monitor the torque value of the preload nut in real time and feed it back to the central control unit.

6. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, It also includes safety protection components, which include a pressure relay and a displacement limit switch. The pressure relay is installed in the hydraulic circuit of the prestress release component and is electrically connected to the central control unit. When the hydraulic circuit pressure exceeds the preset safety pressure, the pressure relay sends a stop signal to the central control unit. The displacement limit switch is installed at the end of the anchor rod extending to the outside of the borehole and is electrically connected to the central control unit. When the locking module of the prestress release component moves to the position of the displacement limit switch, the displacement limit switch sends a stop signal to the central control unit to prevent excessive release of prestress.

7. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The prestress release assembly also includes a displacement encoder, which is installed on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time and convert the angle data into axial displacement data of the locking module, which is then fed back to the central control unit to realize closed-loop control of the prestress release amount.

8. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The prestress release assembly also includes a displacement encoder, which is installed on the driven gear shaft of the transmission module and electrically connected to the central control unit. The displacement encoder is used to monitor the rotation angle of the driven gear in real time and convert the angle data into axial displacement data of the locking module, which is then fed back to the central control unit to realize closed-loop control of the prestress release amount.

9. The active prestress release system for anchor bolts for stability control in deep surrounding rock according to claim 1, characterized in that, The prestressing application component also includes an accumulator, which is connected to the hydraulic cylinder of the prestressing release component and is used to store the pressure energy of the hydraulic oil. After the prestressing release component completes one prestressing release, the accumulator replenishes the hydraulic cylinder with hydraulic oil to provide power for the next prestressing release, reducing the need for continuous power supply from the external hydraulic source.

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