A two-stage yield anchor device and method capable of monitoring preload

Abstract

The present invention discloses a two-stage pressure-yielding anchor rod device and method capable of monitoring preload, which belongs to the field of underground engineering support such as lanes, tunnels and tunnels. It includes a special-shaped anchor rod and a preload monitoring device, etc. The special-shaped anchor rod includes a special-shaped hollow anchor rod and a solid anchor rod that are combined with each other. The solid anchor rod is arranged at the front end of the special-shaped hollow anchor rod, and the end of the special-shaped hollow anchor rod is provided with a sliding cavity that matches the tail of the solid anchor rod. The tail of the solid anchor rod and the sliding cavity of the end of the special-shaped hollow anchor rod are intersected and combined to form a piston structure that can slide relatively. A preload monitoring device is provided at the intersection; when the surrounding rock undergoes large deformation, the device can simultaneously achieve constant resistance large deformation, ensure that the anchor rod and the anchoring structure are not damaged, and can also read the preload. Its structure can not only achieve the pressure-yielding effect, but also accurately monitor the size of the preload in real time. It has the advantages of diverse functions, accurate data, reasonable structure, and economic applicability.

Description

Technical Field

[0001] The invention relates to a two-stage yield anchor device and method capable of monitoring pre-tightening force, and belongs to the field of underground engineering support such as lanes, tunnels and tunnels. Background Art

[0002] In recent years, with the continuous increase in the depth of coal mining and the burial depth of tunnels and tunnels, the resource mining environment and engineering geological conditions faced have become increasingly complex. Deformation and damage are prone to occur due to high ground stress, excavation disturbance or mining. The support problem has become an important task in deep mining and tunnel engineering construction.

[0003] Prestressed anchor bolts are a widely and effectively used support method in underground engineering projects. They actively reinforce the surrounding rock by applying a certain prestress. This requires monitoring the prestress. However, because anchor bolts are concealed supports and extend deep into the surrounding rock, existing methods cannot accurately monitor the applied prestress and the real-time stress changes of the anchor bolts. Furthermore, deep roadways or tunnels are subject to multiple factors, such as high ground stress and weak rock mass, and the surrounding rock is prone to large deformation. This requires anchor bolts to not only provide a constant support force but also generate large elongation deformation to meet the requirements of large deformation. Given these challenges, there is an urgent need to develop an anchor bolt device that can not only provide a constant support force to effectively control surrounding rock deformation, generate large elongation deformation to meet the requirements of large deformation, and accurately monitor the prestress and real-time stress changes of the anchor bolt body. Specifically, an anchor bolt device that integrates precise monitoring, real-time monitoring, constant resistance, and deformation-yielding functions is needed to address these existing engineering and technical challenges. Summary of the Invention

[0004] Technical problem: In order to address the shortcomings of the existing technology, a two-stage pressure-yielding anchor device and method that can monitor the preload force is provided. It can not only accurately monitor the applied prestress and monitor the stress changes of the anchor body in real time, but also provide a constant support force and generate a large elongation deformation to meet the requirements of large deformation of the surrounding rock.

[0005] Technical solution: To achieve the above technical objectives, the present invention provides a two-stage pressure-yielding anchor rod device capable of monitoring preload, comprising a special-shaped anchor rod, wherein the special-shaped anchor rod comprises a special-shaped hollow anchor rod and a solid anchor rod that are combined with each other, the solid anchor rod is arranged at the front end of the special-shaped hollow anchor rod, the end of the special-shaped hollow anchor rod is provided with a sliding cavity that matches the tail of the solid anchor rod, the tail of the solid anchor rod and the sliding cavity at the end of the special-shaped hollow anchor rod are intersected and combined to form a piston structure that can slide relative to each other, and a preload monitoring device is provided at the intersection;

[0006] The tail of the special-shaped hollow anchor rod is provided with a thread, on which a tray and an anti-slip nut are sequentially installed;

[0007] The solid anchor rod comprises a solid anchor rod body, the end of the solid anchor rod body is provided with a resistance-increasing thread for improving the fastening force with the anchor body, the tail of the solid anchor rod body is provided with an enlarged end head for connecting with the special-shaped hollow anchor rod, the end of the special-shaped hollow anchor rod is sleeved on the outside of the enlarged end head, the part of the enlarged end head arranged inside the enlarged end head is provided with a thread, and a plurality of gear dampers are provided between the threads of the special-shaped hollow anchor rod and the enlarged end head, which increase the pulling force as the two slide relative to each other;

[0008] The preload monitoring device comprises a displacement sensor arranged inside the sliding cavity of the special-shaped hollow anchor rod for obtaining the moving distance of the gear damper. The displacement sensor is connected to a comprehensive reading instrument through a data line.

[0009] Furthermore, the sliding cavity at the end of the special-shaped hollow anchor rod is provided with a sealing baffle, so that the enlarged end at the tail of the solid anchor rod can only slide inside the sliding cavity and will not fall out. A high-elasticity spring is provided between the sealing baffle and the enlarged end of the sliding cavity, and a rectangular protrusion is provided on the tail of the solid anchor rod. A groove matching the rectangular protrusion is provided on the sealing baffle. When the high-elasticity spring is not under force and the enlarged end is located at the bottom of the sliding cavity, the rectangular protrusion is just located in the groove, so that the special-shaped hollow anchor rod and the solid anchor rod can rotate synchronously.

[0010] Furthermore, a reserved wiring hole is opened on the side wall of the sliding cavity at the end of the special-shaped hollow anchor rod to allow the data line to pass through, and a plurality of metal displacement sensing nodes are provided on the enlarged end. The displacement sensor determines the distance of movement by reading the metal displacement sensing node corresponding to the current position, thereby converting the movement distance into preload data, and reading it through the integrated reading instrument connected by the data cable.

[0011] Furthermore, the gear damper includes multiple square inner grooves positioned within the sliding cavity of the special-shaped hollow anchor rod, matching the position of the enlarged end. Two to four square inner grooves are evenly distributed across each cross-section of the special-shaped hollow anchor rod's end. Each square inner groove houses a gear bolt that engages with the threaded end of the enlarged end. The gear bolt includes a gear with a threaded rod positioned at the axis of each side of the gear. Each square inner groove contains a bolt hole that matches the threaded rod of the gear bolt. Initially, only one of the bolt holes for the gear bolt connection has clearance, ensuring that the gear bolt can only rotate in the set direction. Movement in the opposite direction is locked, preventing the solid anchor rod from slipping backward when the special-shaped anchor rod penetrates the anchor hole.

[0012] Furthermore, when the surrounding rock undergoes large deformation, the solid anchor rod and the special-shaped hollow anchor rod are subjected to force to produce relative tensile slippage, and the high-elasticity spring is compressed by the enlarged end. Within the allowable range of the high-elasticity spring, the special-shaped anchor rod composed of the solid anchor rod and the special-shaped hollow anchor rod and the surrounding rock are deformed together by the compression of the high-elasticity spring, realizing the pressure-yielding characteristic.

[0013] A method for installing a two-stage yield anchor device capable of monitoring preload force comprises the following steps:

[0014] Construct anchor holes at pre-marked locations in the surrounding rock, assemble the solid anchor rod and the special-shaped hollow anchor rod, so that the enlarged end is at the bottom of the sliding cavity and the high-elasticity spring is not compressed;

[0015] The anchoring agent mortar roll and curing agent roll are sent into the anchor hole through the special-shaped anchor rod, and the stirrer is started to drive the solid anchor rod to rotate and stir. At this time, the solid anchor rod rotates together with the special-shaped hollow anchor rod through the rectangular protrusion;

[0016] The stirrer is used to drive the rotating special-shaped anchor rod to fully mix the mastic and curing agent and form a solidified anchor body after waiting. The tray and anti-slip nut are sequentially installed on the threaded section of the special-shaped hollow anchor rod exposed outside the anchor hole. The pre-tightening force is provided along the thread rise angle by pre-tightening the anti-slip nut. Finally, the data line connected to the displacement sensor is connected to the comprehensive reading instrument set outside the hole.

[0017] A method for operating a two-stage yield anchor device capable of monitoring preload force comprises the following steps:

[0018] When the pre-tightening force is provided along the thread rise angle by the pre-tightening anti-slip nut, the high-elasticity spring is squeezed and compressed by the sealing baffle. At this time, the solid anchor rod and the special-shaped hollow anchor rod slip relative to each other. The position information and sliding distance of the metal displacement sensing node on the expanded end will be sensed by the displacement sensor, and further converted into displacement data: the compression amount of the high-elasticity spring is the sliding distance. Assuming the sliding distance is x and the elastic coefficient of the high-elasticity spring is k, the pre-tightening force F can be calculated by the spring force formula F=kx. The displacement sensor transmits the displacement data to the comprehensive reading instrument through the data line. The comprehensive reading instrument uses the above formula to convert the displacement data into pre-tightening force data.

[0019] When the surrounding rock undergoes a large deformation, the solid anchor rod and the special-shaped hollow anchor rod will slide relative to each other under tension, and the high elastic spring will be further compressed. Within the sliding design range of the expanded end and the index of the high elastic spring, the special-shaped anchor rod will deform together with the surrounding rock through the compression of the high elastic spring, thereby realizing the pressure-yielding characteristic of the device.

[0020] Similarly to the above, the spring compression generated during this period, that is, the relative displacement of the expansion end, is also converted into data by the displacement sensor and read on the integrated reading instrument;

[0021] Thereby, the function of the special-shaped anchor rod releasing pressure can be realized while monitoring the preload force and grasping the stress state of the special-shaped anchor rod in real time.

[0022] Beneficial effects: The present invention has the functions of providing a constant support force, generating a large elongation deformation to meet the requirements of large deformation of the surrounding rock, and accurately monitoring the preload and real-time monitoring of the stress changes of the anchor rod body, which makes up for the defects of existing anchor rods or yield anchor rods that cannot apply preload or the monitoring is inaccurate after the preload is applied. Constant resistance is provided by coordinating the compression characteristics of the high-strength spring and the tension characteristics of the rod body, so that it can deform with the surrounding rock within the allowable range to meet the requirements of large deformation of the surrounding rock; the position information of the metal displacement sensing node can be converted into data by the displacement sensor, so that the size of the applied preload can be accurately monitored; when the anchor rod body deforms and yields, the stress changes of the anchor rod body can also be monitored in real time through the preload monitoring device. The anchor rod device integrates multiple functions in one, which solves the problem that ordinary anchor rods cannot meet the requirements of large deformation of the surrounding rock, solves the problem that existing yield anchor rods cannot apply preload or the monitoring is inaccurate after the preload is applied, and solves the problem that existing methods are difficult to grasp and monitor the dynamic changes of the anchor rod body stress in real time. The present invention has a simple structure, accurate data, and stable functions, and can greatly improve monitoring efficiency. The deformation and pressure-relieving function of the anchor rod can effectively reduce the occurrence of accidents and ensure the safety of workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of anchor holes in an embodiment of the present invention;

[0024] Figure 2 Schematic diagram of the structure of a two-stage yield anchor device capable of monitoring preload force in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of the installation of a two-stage yield anchor device capable of monitoring preload force in an embodiment of the present invention;

[0026] FIG4( a ) is an enlarged schematic diagram of the longitudinal section of the gear bolt in an embodiment of the present invention;

[0027] Figure 4(b) is a schematic diagram of the gear bolt structure in an embodiment of the present invention;

[0028] Figure 5 Schematic diagram of the structure of the preload monitoring device in an embodiment of the present invention.

[0029] In the figure: 1-surrounding rock, 2-special-shaped anchor rod, 3-anti-slip wire nut, 4-tray, 5-anchor hole, 6-special-shaped hollow anchor rod, 7-preload monitoring device, 8-high elastic spring, 9-enlarged end, 10-displacement sensor, 11-solid anchor rod, 12-anchor body, 13-resistance-increasing thread, 14-data line, 15-integrated reading instrument, 16-rectangular protrusion, 17-metal displacement sensing node, 18-gear bolt, 19-square inner groove, 20-reserved wiring hole, 21-bolt hole, 22-solid anchor rod body. DETAILED DESCRIPTION

[0030] The present invention will be further described below with reference to the embodiments in the accompanying drawings:

[0031] like Figure 1 and Figure 2 As shown, the two-stage yield anchor device capable of monitoring preload of the present invention includes a special-shaped hollow anchor 6, a solid anchor 11 and a preload monitoring device 7. The solid anchor 11 is composed of an enlarged end 9 and a solid anchor body 22. The enlarged end 9 is slidable in the special-shaped hollow anchor 6 through the thread on it and the gear bolt 18. The solid anchor body 22 is provided with a resistance-increasing thread 13 on one end that penetrates into the bottom of the anchor hole 5. After the anchoring agent is bonded, the resistance-increasing thread 13 can enhance the anchoring force between the solid anchor 11 and the anchor body 12; the special-shaped hollow anchor 6 is connected to the enlarged end 9 of the solid anchor 11 at one end that penetrates into the anchor hole, and the part exposed to the anchor hole 5 is provided with a thread, and a tray 4 and an anti-slip nut 3 are sequentially arranged on the thread; the end of the solid anchor 11 and the special-shaped hollow anchor 6 are connected and combined with the related components at this position to form a preload monitoring device 7.

[0032] like Figure 3 As shown, the anchoring agent mortar roll, curing agent roll, and the entire anchor rod are inserted into the anchor hole 5, and the agitator is activated to rotate and stir the rod. A rectangular protrusion 16 is provided on the end of the solid anchor rod 11, which fits into a groove reserved at the end of the shaped hollow anchor rod 6, allowing the solid anchor rod 11 to rotate with the shaped hollow anchor rod 6. The agitator drives the shaped hollow anchor rod 6 and the solid anchor rod 11 to rotate, thoroughly mixing the mortar and curing agent to form an anchoring agent colloid. After the anchoring agent solidifies, the tray 4 and anti-slip nut 3 are sequentially installed on the threaded section of the shaped hollow anchor rod 6 exposed outside the anchor hole. The anti-slip nut 3 is preloaded along the thread lead angle. Finally, the other side of the data cable 14 is connected to the integrated reading instrument 15. When the preload force provided by the anti-slip nut 3 along the thread lead angle is applied, the high-elasticity spring 8 is compressed, causing relative slip between the solid anchor rod 11 and the shaped hollow anchor rod 6.

[0033] As shown in Figures 4(a) and 4(b), the end section of the irregularly shaped hollow anchor rod 6 is evenly spaced with two to four square inner grooves 19. Bolt holes 21 are provided on the lower side of the square inner grooves 19, while no bolt holes are reserved on the upper side. The gear bolt 18 is threadedly rotated into the bolt hole 21. Since the bolt hole is only on one side, this restricts the gear bolt 18 to initially rotate only in one direction. This further prevents the solid anchor rod 11 from sliding backward when the anchor rod body penetrates the anchor hole 5.

[0034] like Figure 5As shown, the preload monitoring device 7 is composed of the end of a solid anchor rod 11, the end of a special-shaped hollow anchor rod 6 and a comprehensive reading instrument 15. A high-elasticity spring 8 is provided at the junction of the end of the solid anchor rod 11 and the end of the special-shaped hollow anchor rod 6. The elastic coefficient of the selected high-elasticity spring should be large enough so that even if the anchor rod is broken, it cannot be completely compressed. A displacement sensor 10 is provided on the inner side of the end of the special-shaped hollow anchor rod 6. The displacement sensor 10 is connected to the comprehensive reading instrument 15 through the reserved wiring hole 20 via a data line 14. A metal displacement sensing node 17 is provided on the enlarged end 9. The position information of the metal displacement sensing node 17 can be converted into preload data by the displacement sensor 10 and read on the comprehensive reading instrument 15.

[0035] A two-stage yield anchor device capable of monitoring preload and a method of using the same, comprising the following steps:

[0036] First, drill anchor holes 5 at pre-calibrated locations in surrounding rock 1, slide solid anchor rods 11 into corresponding positions in special-shaped hollow anchor rods 6, and secure them. Connect one side of data cable 14 to displacement sensor 10 through pre-reserved wiring holes 20. At this point, high-elasticity spring 8 is uncompressed.

[0037] Then, the anchoring agent mortar roll, curing agent roll and the entire anchor rod are placed into the anchor hole 5, and the stirrer is started to rotate and stir the rod body. A rectangular protrusion 16 is provided at the end of the solid anchor rod 11, and the rectangular protrusion 16 is embedded in the groove reserved at the end of the special-shaped hollow anchor rod 6, so that the solid anchor rod 11 can rotate together with the special-shaped hollow anchor rod 6; the stirrer is used to rotate the special-shaped hollow anchor rod 6 and the solid anchor rod 11 to fully stir the mortar and curing agent to form an anchoring agent colloid. After waiting for the anchoring agent to solidify, the tray 4 and the anti-slip nut 3 are sequentially installed on the threaded section of the special-shaped hollow anchor rod 6 exposed outside the anchor hole, and the pre-tightening force is provided along the thread rise angle by pre-tightening the anti-slip nut 3. Finally, the other side of the data line 14 is connected to the integrated reading instrument 15.

[0038] When preload is applied along the thread lead angle by pre-tightening the anti-slip nut 3, the highly elastic spring 8 compresses, causing relative slippage between the solid anchor rod 11 and the shaped hollow anchor rod 6. The position and slippage distance of the metal displacement sensing node 17 on the enlarged end 9 are sensed by the displacement sensor 10 and converted into displacement data. The compression of the highly elastic spring is the slippage distance. Assuming the slippage distance is x, the preload force can be calculated using the spring force formula F = kx. The displacement sensor 10 transmits the displacement data via the data line 14 to the integrated reader 15, which uses the above formula to convert the displacement data into preload force data.

[0039] When the surrounding rock 1 undergoes significant deformation, the solid anchor 11 and the shaped hollow anchor 6 undergo relative slippage due to tension, further compressing the highly elastic spring 8. Within the permitted range, the anchor body deforms along with the surrounding rock 1 compressed by the highly elastic spring 8, thereby achieving the device's pressure-yielding characteristic. Similarly, the resulting spring compression relative to displacement is still converted into data by the displacement sensor 10 and read on the integrated reader 15. In summary, this device not only monitors preload and provides real-time information on the anchor body's stress state, but also achieves pressure-yielding performance.

Claims

1. A two-stage yield anchor device capable of monitoring preload force, characterized by: The invention comprises a special-shaped anchor rod (2), wherein the special-shaped anchor rod (2) comprises a special-shaped hollow anchor rod (6) and a solid anchor rod (11) which are combined with each other, wherein the solid anchor rod (11) is arranged at the front end of the special-shaped hollow anchor rod (6), and the end of the special-shaped hollow anchor rod (6) is provided with a sliding cavity which matches the tail of the solid anchor rod (11), and the tail of the solid anchor rod (11) and the sliding cavity of the end of the special-shaped hollow anchor rod (6) are connected and combined to form a piston structure which can slide relative to each other, and a preload monitoring device (7) is provided at the connection; The tail of the special-shaped hollow anchor rod (6) is provided with a thread, on which a tray (4) and an anti-slip nut (3) are sequentially mounted; The solid anchor rod (11) includes a solid anchor rod body (22), the end of the solid anchor rod body (22) is provided with a resistance-increasing thread (13) for increasing the fastening force with the anchor body (12), the tail of the solid anchor rod body (22) is provided with an enlarged end head (9) for connecting with the special-shaped hollow anchor rod (6), the end of the special-shaped hollow anchor rod (6) is sleeved on the outside of the enlarged end head (9), the part of the enlarged end head (9) arranged inside the enlarged end head (9) is provided with a thread, and a plurality of gear dampers are provided between the threads of the special-shaped hollow anchor rod (6) and the enlarged end head (9) so as to increase the pulling force as the two slide relative to each other; The preload monitoring device (7) includes a displacement sensor (10) arranged inside the sliding cavity of the special-shaped hollow anchor rod (6) for obtaining the moving distance of the gear damper, and the displacement sensor (10) is connected to the integrated reading instrument (15) through a data line (14); the sliding cavity at the end of the special-shaped hollow anchor rod (6) is provided with a sealing baffle, so that the enlarged end (9) at the tail of the solid anchor rod (11) can only slide inside the sliding cavity and will not fall out, a high elastic spring (8) is provided between the sealing baffle and the enlarged end (9) of the sliding cavity, a rectangular protrusion (16) is provided on the tail of the solid anchor rod (11), and a groove matching the rectangular protrusion (16) is provided on the sealing baffle. When the high elastic spring (8) is not subjected to force and the enlarged end (9) is located at the bottom of the sliding cavity, the rectangular protrusion (16) is just located in the groove, so that the special-shaped hollow anchor rod (6) and the solid anchor rod (11) can rotate synchronously.

2. A two-stage yield anchor device capable of monitoring preload force according to claim 1, characterized in that: A reserved wiring hole (20) is provided on the side wall of the sliding cavity at the end of the special-shaped hollow anchor rod (6) to allow the data line (14) to pass through. A plurality of metal displacement sensing nodes (17) are provided on the enlarged end (9). The displacement sensor (10) determines the distance moved by reading the metal displacement sensing node (17) corresponding to the current position, thereby converting the moving distance into preload data, and reading the data through the integrated reading instrument (15) connected to the data line (14).

3. The two-stage yield anchor device capable of monitoring preload force according to claim 1, characterized in that: The gear damper includes a plurality of square inner grooves (19) arranged in the sliding cavity of the special-shaped hollow anchor rod (6) and matching the position of the enlarged end head (9). 2 to 4 square inner grooves (19) are evenly arranged on each cross section of the end of the special-shaped hollow anchor rod (6). A gear bolt (18) is provided in the square inner groove (19) and is engaged with the thread on the enlarged end head (9). The gear bolt (18) includes a gear, and a threaded rod is provided at the axis of both sides of the gear. A bolt hole (21) matching the threaded rod of the gear bolt (18) is provided in each square inner groove (19). In the initial state, only one side of the bolt hole (21) connected to the gear bolt (18) has a margin, thereby ensuring that the gear bolt (18) can only rotate in the set direction, and is locked in the opposite direction, thereby preventing the solid anchor rod (11) from sliding backward when the special-shaped anchor rod (2) penetrates into the anchor hole (5).

4. A two-stage yield anchor device capable of monitoring preload force according to claim 3, characterized in that: When the surrounding rock (1) undergoes a large deformation, the solid anchor rod (11) and the special-shaped hollow anchor rod (6) are subjected to force to produce relative tensile slippage, and the high elastic spring (8) is compressed by the enlarged end (9). Within the allowable range of the high elastic spring (8), the special-shaped anchor rod (2) composed of the solid anchor rod (11) and the special-shaped hollow anchor rod (6) and the surrounding rock (1) are compressed by the high elastic spring (8) to deform together, thereby realizing the pressure-yielding characteristic.

5. A method for installing a two-stage pressure-yielding anchor device capable of monitoring preload force according to any one of claims 1 to 4, characterized in that Here are the steps: An anchor hole (5) is constructed at a pre-marked position in the surrounding rock (1), and the solid anchor rod (11) and the special-shaped hollow anchor rod (6) are assembled. At this time, the enlarged end (9) is located at the bottom of the sliding cavity, and the high elastic spring (8) is not compressed; The anchoring agent mortar roll and the curing agent roll are fed into the anchor hole (5) through the special-shaped anchor rod (2), and the stirrer is started to drive the solid anchor rod (11) to rotate and stir. At this time, the solid anchor rod (11) rotates together with the special-shaped hollow anchor rod (6) through the rectangular protrusion (16); A stirrer is used to drive the rotating special-shaped anchor rod (2) to fully stir the mortar and the curing agent and form a solidified anchor body (12) after waiting. A tray (4) and an anti-slip nut (3) are sequentially mounted on the threaded section of the special-shaped hollow anchor rod (6) exposed outside the anchor hole (5). A pre-tightening force is provided along the thread rise angle by pre-tightening the anti-slip nut (3). Finally, a data line (14) connected to the displacement sensor (10) is connected to a comprehensive reading instrument (15) set outside the hole.

6. A method for operating a two-stage yield anchor device capable of monitoring preload according to any one of claims 1 to 5, characterized in that Here are the steps: When the pre-tightening force is provided along the thread rise angle by the pre-tightening anti-slip nut (3), the high elastic spring (8) is squeezed and compressed by the sealing baffle. At this time, the solid anchor rod (11) and the special-shaped hollow anchor rod (6) slide relative to each other. The position information and sliding distance of the metal displacement sensing node (17) on the enlarged end (9) will be sensed by the displacement sensor (10) and further converted into displacement data: the compression amount of the high elastic spring is the sliding distance. Assume that the sliding distance is x , the elastic constant of the high elastic spring is k , the spring force formula can be used to F = kx Calculated preload F , the displacement sensor (10) transmits the displacement data to the integrated reading instrument (15) via the data line (14), and the integrated reading instrument (15) converts the displacement data into preload data using the above formula; When the surrounding rock (1) undergoes a large deformation, the solid anchor rod (11) and the special-shaped hollow anchor rod (6) will slide relative to each other under tension, and the high elastic spring (8) will be further compressed. Within the sliding design range of the expanded end (9) and the index of the high elastic spring (8), the special-shaped anchor rod (2) will deform together with the surrounding rock (1) through the compression of the high elastic spring (8), thereby realizing the pressure-yielding characteristic of the device; Similarly to the above, the spring compression generated during the period, that is, the relative displacement of the expansion end (9), is also converted into data by the displacement sensor (10) and read on the integrated reading instrument (15); Thus, the function of releasing the pressure of the special-shaped anchor rod (2) can be achieved while monitoring the preload force and grasping the stress state of the special-shaped anchor rod (2) in real time.

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