Anchoring section self-expansion locking structure and anchor cable type rock mass stress and strain monitoring method

Abstract

The invention provides an anchoring section self-expansion locking structure and an anchor cable type rock mass stress and strain monitoring method. The anchoring section self-expansion locking structure comprises an anchoring section self-expansion locking anchor cable, and the anchoring section self-expansion locking anchor cable comprises self-expansion anchoring slurry, a magnetic anchor cable, an anchor cable type rock mass stress sensor, a combined strain sensor and a test analysis system; the magnetic anchor cable is anchored in an anchor hole of a side slope through self-expansion anchoring slurry; the anchor cable type rock mass stress sensor is arranged at a hole opening part of an anchor hole and is used for detecting the stress of the magnetic anchor cable; the combined strain sensor is arranged on the inner side wall of the anchor hole; and the anchor cable type rock mass stress sensor and the combined strain sensor are connected with the test analysis system through signal lines. According to the locking structure, based on the fact that the anchoring section is a key factor for determining the performance of the anchor cable, by increasing the pulling resistance of the anchor cable, on one hand, the reinforcing effect of the anchor cable on a slope can be improved, and on the other hand, guarantee is provided for the stability of long-term real-time monitoring of rock stress and strain.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical engineering monitoring, and in particular to an anchoring section self-expansion locking structure and an anchor cable type rock mass stress and strain monitoring method. Background Art

[0002] In slope management projects, by monitoring the slope, we can timely understand the working state of the slope during the construction and operation periods, and timely propose treatment plans and measures. We can achieve information construction to reduce unnecessary losses and ensure the safety of the project during the construction and operation periods. At present, slope monitoring is not timely and accurate, has low safety and reliability, cannot be monitored in real time throughout the process, cannot achieve the combination and connection of safety monitoring during the construction period and the operation area, and has many and cumbersome instruments.

[0003] The arrangement of the rock mass stress monitoring system is mainly added to the slope reinforcement system. Anchor (cable) reinforcement is a common means of slope management. The length design of the anchoring section of the prestressed anchor cable is the key. In order to ensure the safety and economy of the anchor cable design, the bonding capacity provided by the anchor cable should be fully utilized to design a reasonable anchoring depth. However, due to the complex stress of the anchor cable anchoring section, the current design method of the anchoring section of the grouting anchoring form in my country is to assume that the shear stress on the bonding surface between the anchor cable and the cement slurry is uniformly distributed. According to the static equilibrium condition, the design length of the anchor cable is obtained by the single hole design tonnage and the average shear stress determined by the pull-out test. Summary of the invention

[0004] The present invention provides an anchoring section self-expanding locking structure and an anchor-type rock stress and strain monitoring method. The locking structure of the present invention is based on the fact that the anchoring section is a key factor in determining the performance of the anchor cable. By increasing the pull-out resistance of the anchor cable, on the one hand, the reinforcement effect of the anchor cable on the slope can be improved, and on the other hand, it provides a guarantee for the stability of long-term real-time monitoring of rock stress and strain.

[0005] In order to realize the above technical features, the object of the present invention is achieved as follows: an anchoring section self-expanding locking structure, comprising an anchoring section self-expanding locking anchor cable, the anchoring section self-expanding locking anchor cable comprising a self-expanding anchor slurry, a magnetic anchor cable, an anchor cable type rock stress sensor, a combined strain sensor, and a test and analysis system; The magnetic anchor cable is anchored inside the anchor hole of the slope by means of self-expanding anchor slurry; The anchor cable type rock stress sensor is arranged at the hole opening of the anchor hole and is used to detect the stress of the magnetic anchor cable; The combined strain sensor is arranged on the inner wall of the anchor hole; The anchor-rope type rock stress sensor and the combined strain sensor are connected to the test and analysis system via a signal line.

[0006] When the anchoring section self-expanding locking anchor cable is used for slope anchoring, it is restricted in the anchor hole by the expansion of the self-expanding anchor slurry, and the anchor body will generate radial pressure on the magnetic anchor cable and the anchor hole wall, thereby strengthening the restraining force of the anchor body and realizing the self-locking of the magnetic anchor cable in the hole.

[0007] The self-expanding anchoring slurry uses cement slurry as the base liquid, adds 5%-20% by weight of magnetic powder to achieve high-density anchoring; and simultaneously adds 15%-30% by weight of an expansion agent to achieve volume expansion, so as to realize self-locking of the anchoring section.

[0008] The magnetic anchor cable is processed by a magnetizer and has magnetism. After the self-expanding anchoring slurry is injected, the magnetic anchor cable expands in an outward drum-like manner with the magnetic anchor cable as the center.

[0009] The combined strain sensor is evenly attached to the middle part of the cylindrical surface and the side wall of the anchoring section. There are two ways to attach the strain sensor to the side wall of the anchoring section: first, the strain gauges are arranged alternately horizontally and vertically along the expansion direction of the cylindrical side; second, the strain gauges are arranged alternately horizontally and vertically along the axial direction.

[0010] The combined strain sensor is composed of a sensitive grid, a substrate, a cover plate, and a lead wire. The sensitive grid is located between the cover plate and the substrate. The lead wire is bonded to the cover plate and connected to a test and analysis system through the lead wire.

[0011] A method for monitoring rock stress and strain using an anchor cable, the monitoring method being implemented using the anchor section self-expansion locking structure, comprising the following steps: Step 1: Drilling of anchor holes on the slope: Use a hollow drill to drill anchor holes according to the designed size. The specific size is adjusted according to the engineering design needs. Arrange a combined strain sensor on the inner wall of the anchor hole, and evenly apply epoxy resin latex on both sides of the strain gauge for water-proof and heat-insulating treatment. Step 2, preparation of self-expanding anchoring slurry: A self-expanding anchor slurry with good pull-out resistance is prepared according to a certain water-cement ratio, magnetic powder content, and expansion agent content. The expansion agent reacts chemically with cement to expand in volume. When there is a lateral limit, the surrounding rock provides a lateral limit to limit the volume expansion of the anchor body, making the anchor body denser and the outer surface of the anchor body smooth and dense. Step 3: Implantation and pouring of magnetic anchor cables: The magnetic anchor cable is implanted into the anchor hole, and then the self-expanding anchor slurry is injected into the anchor hole; Step 4: Burying and installation of anchor type rock stress sensor: Before tensioning the anchor cable, install the anchor cable rock stress sensor on the hole pad, adjust the dynamometer, anchor, jack and hole axis vertically, the deflection should be less than 0.5°, and the eccentricity should be less than 5mm. After connecting the oil inlet and return ports of the jack, load slowly at a rate of 0.1MPa / min and tension the anchor cable so that the entire anchor cable loading system is in close contact. Step 5: Real-time monitoring of tension and stress of magnetic anchor cables: After the magnetic anchor cable is tensioned, the jack returns oil. After the reference value is determined, the load is added and tensioned in stages. Tensioning observation is carried out step by step. Each load is measured and read once. The last load is observed for stability. The load is measured once every 5 minutes. If the difference between three consecutive readings is less than 1%, it is considered stable. The locking load is measured and read in time. Step 6. Data monitoring and data analysis: Connect the test and analysis system to observe the long-term stress of the anchor cable. At the same time, install a protective device on the cable line and conduct a 0.5kg impact test. The impact is successfully resisted and there is no obvious fluctuation in the transmission data. Then, a curve chart of the change of anchor cable prestress over time is obtained. Step 7: Anchor failure stress and strain prediction analysis: Using the acquired stress-strain monitoring data, the state of the slope at a certain moment in the future is predicted through grey theory model prediction, time series model prediction method or statistical regression prediction model.

[0012] Beneficial effects of the present invention: 1. Aiming at the problems of untimely and inaccurate slope monitoring, low safety and reliability, and inability to monitor the entire process in real time, the present invention proposes a stress monitoring technology for the self-expanding locking anchor cable in the anchoring section, and further proposes an anchor cable failure early warning analysis scheme.

[0013] 2. The present invention adopts a self-expanding anchor slurry in the anchoring segment self-expanding locking anchor cable. In ordinary slurry, additives such as magnetic powder and expansion agent are added. When there is a lateral limit pressure of the anchor hole, the lateral pressure increases under the action of the expansion agent, and the anchoring segment is squeezed to achieve self-locking and enhance the pull-out resistance. When the lateral limit pressure of the anchor hole is insufficient, the slurry is driven by the magnetic powder and gathers around the magnetic anchor cable to enhance the anchoring bonding performance.

[0014] 3. In the combined strain sensor adopted by the present invention, the strain gauges are arranged alternately horizontally and vertically. When there is eccentric stress, one side is pulled and the other side is compressed, resulting in opposite changes, which can reduce the influence of bending moment. The horizontally pasted strain gauge is a temperature compensation gauge to improve the sensitivity.

[0015] 4. The combined strain sensor strain gauges R1R2 and R3R4 proposed in the present invention are placed in series in two pairs of arms, R=R1=R2=R3=R4, and R1R2R3R4 test the strain in the same direction. Therefore, when connected in series in a circuit, the superposition of resistances reflects the resultant force in this direction.

[0016] 5. The present invention proposes long-term stress observation of anchor cables. By conducting a 0.5kg impact test, the impact can be successfully resisted, and the transmitted data has no obvious fluctuation, and then a long-term stress curve is obtained.

[0017] 6. The present invention proposes that the measured long-term stress-strain data can be processed by the test analysis system to obtain a corresponding early warning plan according to the actual working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 It is a schematic diagram of the application of the self-expansion locking technology of the slope anchor cable type anchoring section involved in the present invention.

[0020] Figure 2 This is a schematic diagram of layered test points of the anchor type rock stress sensor involved in the present invention.

[0021] Figure 3 (a) and (b) are structural diagrams of the combined strain sensor involved in the present invention during the actual installation process.

[0022] Figure 4 (a) and (b) are connection circuit diagrams of two different connection methods of the combined strain sensor involved in the present invention.

[0023] Figure 5 It is a schematic diagram of the forces acting on the inner and outer rings after the self-expanding anchor body involved in the present invention exerts its expansion effect.

[0024] Figure 6 (a)(b)(c)(d) are real-time stress monitoring data diagrams of the test and analysis system involved in the present invention.

[0025] Figure 7 This is a flow chart of the early warning solution of the test and analysis system involved in the present invention.

[0026] In the figure: anchor hole 1, anchor section self-expanding locking anchor cable 2, self-expanding anchor slurry 3, magnetic anchor cable 4, anchor cable type rock stress sensor 5, combined strain sensor 6, test and analysis system 7. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0028] Embodiment 1: like Figure 1-7 As shown, an anchoring section self-expanding locking structure includes an anchoring section self-expanding locking anchor cable 2, wherein the anchoring section self-expanding locking anchor cable 2 includes a self-expanding anchoring slurry 3, a magnetic anchor cable 4, an anchor cable type rock stress sensor 5, a combined strain sensor 6, and a testing and analysis system 7; the magnetic anchor cable 4 is anchored inside an anchor hole 1 of a slope by means of the self-expanding anchoring slurry 3; the anchor cable type rock stress sensor 5 is arranged at the hole opening of the anchor hole 1 and is used to detect the stress of the magnetic anchor cable 4; the combined strain sensor 6 is arranged on the inner side wall of the anchor hole 1; the anchor cable type rock stress sensor 5 and the combined strain sensor 6 are connected to the testing and analysis system 7 via a signal line.

[0029] The present invention is based on the fact that the anchoring section is a key factor in determining the performance of the anchor cable. Therefore, increasing the pull-out resistance of the anchor cable can, on the one hand, enhance the reinforcement effect of the anchor cable on the slope, and on the other hand, provide a guarantee for the stability of long-term real-time monitoring of rock stress and strain.

[0030] This technology can achieve the following: ① Under the same anchoring length, the anchoring force can be increased by 170%-240%, and the stress-strain monitoring range of the anchor cable can be enhanced; ② Under the same anchoring force, the amount of anchor cables and anchoring materials can be saved, saving costs.

[0031] Furthermore, when the anchoring section self-expanding locking anchor cable 2 is used for slope anchoring, it is restricted in the anchor hole 1 by the expansion of the self-expanding anchoring slurry 3, and the anchor body will generate radial pressure on the magnetic anchor cable 4 and the wall of the anchor hole 1, thereby strengthening the restraining force of the anchor body and achieving self-locking of the magnetic anchor cable 4 anchored in the hole 1.

[0032] Furthermore, the self-expanding anchoring slurry 3 is composed of cement slurry as the base liquid, and magnetic powder is added in a weight ratio of 5%-20% to achieve high-density anchoring; at the same time, an expansion agent is added in a weight ratio of 15%-30% to achieve volume expansion, so as to realize self-locking of the anchoring section.

[0033] Preferably, when the amount of expansion agent in the self-expanding locking anchor cable in the anchoring section is 15%, a significant head expansion effect will occur at the anchoring end, and the pull-out resistance increases from 3.9KN to 18.6KN, an increase of 480%; the pull-out resistance of the rock anchor increases from 341kN to 560kN, an increase of 164%. It can be seen that the self-expanding high-strength pre-stressed anchoring technology can significantly improve the pull-out resistance, make it difficult to pull out, and achieve self-locking.

[0034] Furthermore, the magnetic anchor cable 4 is processed by a magnetizer and has magnetism, and after the self-expanding anchoring slurry 3 is injected, it expands in an outward drum-like manner with the magnetic anchor cable 4 as the center.

[0035] Furthermore, the combined strain sensor 6 is evenly attached to the middle part of the cylindrical surface and the side wall of the anchoring section. There are two ways to attach the strain sensor 6 to the side wall of the anchoring section: first, the strain gauges are arranged alternately horizontally and vertically along the expansion direction of the cylindrical side; second, the strain gauges are arranged alternately horizontally and vertically along the axial direction.

[0036] Furthermore, the combined strain sensor 6 is composed of a sensitive grid, a substrate, a cover plate, and leads. The sensitive grid is located between the cover plate and the substrate, and the leads are bonded to the cover plate and connected to the test and analysis system through the leads.

[0037] Epoxy resin latex is evenly coated on both sides of the combined strain sensor for water-proof and heat-insulating treatment to prevent moisture and temperature from interfering with the strain sensor.

[0038] In the preferred solution, the self-expanding anchoring slurry mainly uses the expansive cement slurry as the anchor body of the anchor rod, and limits the expansion of the expansive slurry by the surrounding rock, thereby generating radial expansion compressive stress to achieve the purpose of improving the ultimate pull-out resistance of the anchor rod. The working principle of the self-expanding anchoring slurry mainly depends on the chemical reaction of the expansive agent. The chemical reaction equation of the expansive agent is: Al2O3+3(CaSO4·2H2O)+3Ca(OH)2+23H2O→3CaO·Al2O3·3CaSO4·32H2O (calcium sulfate).

[0039] In the preferred embodiment, the magnetic anchor cable and the self-expanding anchor slurry expand and diffuse outwardly under the action of magnetic attraction, which can reduce the cracks and dispersion of the anchor body due to the addition of the expansion agent and avoid the situation where the anchor body is easily lost due to the unconfined slurry.

[0040] In the preferred solution, the strain gauges are arranged alternately horizontally and vertically. When there is eccentric stress, one side is pulled and the other side is compressed, resulting in opposite changes, which can reduce the influence of bending moment. The horizontally pasted strain gauge is a temperature compensation gauge, which has the effect of improving sensitivity.

[0041] In the preferred solution, the combined strain sensor test principle is that the solid cylinder is deformed under the action of external force F, and the strain generated by the external force is: ; Where: l is the length of the elastic element; S is the cross-sectional area of ​​the elastic element; F is the external force; σ is the stress; E is the elastic modulus.

[0042] Embodiment 2: An anchoring section self-expansion locking technology and anchor-type rock stress and strain monitoring technology, anchoring section self-expansion locking technology analysis mechanism, including the following steps: based on CT scanning technology, the expansion agent anchor body test is carried out to study the anchor body radial expansion, anchor body annular expansion force, anchor body density stratification phenomenon Step 1. Analysis of radial mechanical mechanism: It can be seen that the radial static balance is: ,Right now: ; ; definition is the inner and outer radial expansion coefficient, because ,so , that is, the radial force on the inner ring is greater than the radial force on the outer ring.

[0043] Step 2: Circumferential mechanical mechanism stress analysis: The anchor body with a mass fraction of 10% expansion agent was selected as a test example. The anchor body was divided into 5 ring areas with equal distance along the radial direction, and a pressure sensor 5 was arranged in each ring to monitor the stable pressure value of each ring after the anchor body was finally set. The annular expansion force on the outer ring is greater than that on the inner ring, that is, .

[0044] definition is the hoop expansion coefficient, because Therefore, the outer ring is more compacted and the anchor body is denser, that is, the CT value of the outer ring is larger than that of the inner ring.

[0045] Step 3, density stratification phenomenon analysis: From the above anchor body radial expansion force analysis and anchor body circumferential expansion force analysis, it can be seen that the density of the outer ring anchor body is greater. In order to further study the anchoring mechanism of the expansion anchor body, the analysis is carried out from the two conditions of constraint force and no constraint force. State a represents the anchor body under the condition of constraint and no expansion force. , In this state, the CT scanning results show that the anchor body is a uniform body, that is, the CT values ​​of each layer of the anchor body are similar.

[0046] State b represents the anchor body without constraints and with expansion force. , .in: is the diameter expansion, , M is a constant. In this state, the CT scanning results show that the anchor body is a homogeneous body, that is, the CT values ​​of each layer of the anchor body are similar, but the overall CT value of state b is greater than that of state a.

[0047] State c represents the anchor body under the condition of constraint and expansion force. , .in: is the diameter compression after constraint is applied, ,and This indicates that the compression of the outer ring diameter is much greater than that of the inner ring diameter, that is, This indicates that the outer ring anchor body is squeezed more densely, so the CT value of the outer ring anchor body is greater than that of the inner ring.

[0048] Based on the analysis of different working conditions with or without constraint force, the outer ring of the anchor body with different mass fractions of expansion agent is denser than the inner ring, and the CT value is larger; under the lateral limit condition, with the increase of the mass fraction of the expansion agent, the compressive stress of the outer ring is greater than that of the inner ring, causing the outer ring of the anchor body to be denser than the inner ring; this phenomenon is consistent with the phenomenon that the contact interface between the hand and the sponge is dense when the hand holds the sponge tightly, while the middle of the sponge is relatively loose. This mechanism explains why a large amount of expansion agent is used in anchor support to improve the ultimate pull-out resistance.

[0049] Step 4. Comparative analysis of radial and circumferential expansion coefficients: In view of the pressure test results of the above tests: the radial and annular expansion coefficients are compared and specific examples are given.

[0050] Divided by test circle: ,so ; According to the test results ,so Therefore, after the expansion effect of the self-expanding anchor body is exerted, the forces on the inner and outer rings are calculated as follows: Inner ring compression area: ; Outer ring compression area: ; Since the hoop expansion coefficient , radial expansion coefficient ,so , substituting it into the above formula, we get: The difference between the compression areas of the inner and outer rings: ; Take again , so the unit strain is: ; have to: ; It can be seen that after the expansion, the outer ring of the anchor body is compressed. >>Inner ring compression area , further verifying that the density of the same layer of the expansion anchor body shows a ring-dividing phenomenon, and the density changes linearly from the outer ring area to the inner ring area.

[0051] Embodiment 3: A method for monitoring rock mass stress and strain using an anchor cable, the monitoring method being implemented using the anchor section self-expansion locking structure, comprising the following steps: Step 1: Drilling of anchor holes on the slope: Use a hollow drill to drill an anchor hole 1 according to the designed size. The specific size is adjusted according to the engineering design requirements. Arrange a combined strain sensor 6 on the inner wall of the anchor hole. Evenly apply epoxy resin latex on both sides of the strain gauge to perform water-proof and heat-insulating treatment. Step 2, preparation of self-expanding anchoring slurry 3: A self-expanding anchor slurry with good pull-out resistance is prepared according to a certain water-cement ratio, magnetic powder content, and expansion agent content, wherein the expansion agent reacts chemically with cement to expand in volume. When there is a restrained lateral limit, the surrounding rock provides a lateral limit to limit the volume expansion of the anchor body, making the anchor body denser and the outer surface of the anchor body smooth and dense; Step 3, implantation and pouring of magnetic anchor cable 4: The magnetic anchor cable 4 is implanted into the anchor hole 1, and then the self-expanding anchor slurry 3 is injected into the anchor hole 1; Step 4: Burying and installation of anchor type rock stress sensor 5: Before tensioning the anchor cable, install the anchor cable rock stress sensor 5 on the hole pad, adjust the dynamometer, anchor, jack and hole axis vertically, the deflection should be less than 0.5°, and the eccentricity should be less than 5mm. After connecting the oil inlet and return ports of the jack, load slowly at a rate of 0.1MPa / min and tension the anchor cable so that the entire anchor cable loading system is in close contact with each other; Step 5: Real-time monitoring of tension and stress of magnetic anchor cable 4: After the magnetic anchor cable 4 is tensioned, the jack returns oil, and after the reference value is determined, the load is added and tensioned in stages, and tensioning observations are carried out step by step. Each level of load is measured and read once, and the last level of load is observed for stability. It is measured once every 5 minutes. If the difference between three consecutive readings is less than 1%, it is stable, and the locking load is measured and read in time; Step 6. Data monitoring and data analysis: Connect the test and analysis system 7 to observe the long-term stress of the anchor cable. At the same time, install a protective device on the cable line and conduct a 0.5kg impact test. The impact is successfully resisted and there is no obvious fluctuation in the transmission data. Then, a curve of the change of anchor cable prestress over time is obtained. Step 7: Anchor failure stress and strain prediction analysis: Using the acquired stress-strain monitoring data, the state of the slope at a certain moment in the future is predicted through grey theory model prediction, time series model prediction method or statistical regression prediction model.

Claims

1. An anchoring segment self-expanding locking structure, characterized in that: It comprises an anchoring section self-expanding locking anchor cable (2), wherein the anchoring section self-expanding locking anchor cable (2) comprises a self-expanding anchoring slurry (3), a magnetic anchor cable (4), an anchor cable type rock mass stress sensor (5), a combined strain sensor (6), and a test and analysis system (7); The magnetic anchor cable (4) is anchored inside the anchor hole (1) of the slope by means of a self-expanding anchoring slurry (3); The anchor-type rock stress sensor (5) is arranged at the hole opening of the anchor hole (1) and is used to detect the stress of the magnetic anchor cable (4); The combined strain sensor (6) is arranged on the inner wall of the anchor hole (1); The anchor-type rock stress sensor (5) and the combined strain sensor (6) are connected to the test and analysis system (7) via a signal line.

2. The anchoring segment self-expanding locking structure according to claim 1, characterized in that: When the anchoring section self-expanding locking anchor cable (2) is used for slope anchoring, it is restricted in the anchor hole (1) by the expansion of the self-expanding anchoring slurry (3), and the anchor body generates radial pressure on the magnetic anchor cable (4) and the wall of the anchor hole (1), thereby strengthening the restraining force of the anchor body and achieving self-locking of the magnetic anchor cable (4) anchored in the hole (1).

3. The anchoring segment self-expanding locking structure according to claim 1, characterized in that: The self-expanding anchoring slurry (3) is composed of cement slurry as a base liquid, and magnetic powder is added in a weight ratio of 5%-20% to achieve high-density anchoring; at the same time, an expansion agent is added in a weight ratio of 15%-30% to achieve volume expansion, so as to achieve self-locking of the anchoring section.

4. The anchoring segment self-expanding locking structure according to claim 1, characterized in that: The magnetic anchor cable (4) is processed by a magnetizer and has magnetism, and after the self-expanding anchoring slurry (3) is injected, it expands in an outward-bulging manner with the magnetic anchor cable (4) as the center.

5. The anchoring segment self-expanding locking structure according to claim 1, characterized in that: The combined strain sensor (6) is evenly attached to the middle part of the cylindrical surface and the side wall of the anchoring section. There are two ways to attach the strain sensor (6) to the side wall of the anchoring section: first, the strain gauges are arranged alternately horizontally and vertically along the expansion direction of the cylindrical side surface; second, the strain gauges are arranged alternately horizontally and vertically along the axial direction.

6. The anchoring segment self-expanding locking structure according to claim 5, characterized in that: The combined strain sensor (6) is composed of a sensitive grid, a substrate, a cover plate, and a lead wire. The sensitive grid is located between the cover plate and the substrate. The lead wire is bonded to the cover plate and connected to a test and analysis system via the lead wire.

7. An anchor-type rock mass stress and strain monitoring method, characterized in that: The monitoring method is implemented by using the anchoring segment self-expanding locking structure according to any one of claims 1 to 6, and comprises the following steps: Step 1: Drilling of anchor holes on the slope: Drill an anchor hole (1) according to the designed size using a hollow drill, the specific size is adjusted according to the engineering design requirements, arrange a combined strain sensor (6) on the inner wall of the anchor hole, and evenly apply epoxy resin latex on both sides of the strain gauge to perform water-proof and heat-insulating treatment; Step 2. Preparation of self-expanding anchoring slurry (3): A self-expanding anchor slurry (3) with good pull-out resistance is prepared according to a certain water-cement ratio, magnetic powder content, and expansion agent content, wherein the expansion agent reacts chemically with cement to expand in volume. When there is a lateral limit, the surrounding rock provides a lateral limit to limit the volume expansion of the anchor body, making the anchor body denser and the outer surface of the anchor body smooth and dense; Step 3: Implantation and pouring of magnetic anchor cable (4): The magnetic anchor cable (4) is implanted into the anchor hole (1), and then the self-expanding anchor slurry (3) is injected into the anchor hole (1); Step 4: Burying and installing the anchor-type rock stress sensor (5): Before tensioning the anchor cable, install the anchor cable rock stress sensor (5) on the hole pad, adjust the dynamometer, anchor, and jack to be perpendicular to the hole axis, the deflection should be less than 0.5°, and the eccentricity should be less than 5 mm. After connecting the oil inlet and return ports of the jack, load slowly at a rate of 0.1 MPa / min and tension the anchor cable so that the entire anchor cable loading system is in close contact with each other; Step 5: Real-time monitoring of the tension and stress of the magnetic anchor cable (4): After the tensioning of the magnetic anchor cable (4) is completed, the oil in the jack is returned. After the reference value is determined, the tensioning is carried out in stages, and the tensioning observation is carried out step by step. The load is measured once for each stage, and the stability observation is carried out for the last stage of load. The reading is measured once every 5 minutes. If the difference between three consecutive readings is less than 1%, it is considered stable, and the locking load is measured in time; Step 6. Data monitoring and data analysis: Connect the test and analysis system (7) to observe the long-term stress of the anchor cable, and install a protective device on the cable line to conduct a 0.5 kg impact test, thereby successfully resisting the impact, and the transmission data has no obvious fluctuations, thereby obtaining a curve diagram of the change of anchor cable prestress over time; Step 7: Anchor failure stress and strain prediction analysis: Using the acquired stress-strain monitoring data, the state of the slope at a certain moment in the future is predicted through grey theory model prediction, time series model prediction method or statistical regression prediction model.

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