Deep roadway stability regulation method

Abstract

The present application relates to roadway supporting technical field, especially to a kind of deep roadway stability regulation method, comprising: S1, in the roadway to be detected selects multiple detection positions, in the detection position, the anchoring force of anchor rod cable is detected;S2, anchor rod cable that anchoring force does not satisfy design requirement is further detected, and anchoring failure reason is determined according to detection result analysis;S3, at least one anchoring body of the detection position is taken out, the anchoring body is detected, and anchoring failure reason is determined according to detection result analysis;S4, the anchoring failure reason determined by combining anchor rod cable detection analysis and the anchoring failure reason determined by anchoring body detection analysis, the reason that influences roadway stability is determined by analysis.This application carries out fine analysis and classification to failure reason, and specific regulation method is proposed for specific lithology and anchoring agent distribution form, which makes up the limitation of the method for judging roadway stability by doing physical and mechanical experiment and peeping on surrounding rock.

Description

Technical Field

[0001] This invention relates to the field of tunnel support technology, and in particular to a method for controlling the stability of deep tunnels. Background Technology

[0002] Deformation and instability of surrounding rock in deep roadways are widespread, but the process of deformation and instability is time-dependent. Generally, deformation and instability occur only after a rapid deceleration phase, a slow deceleration phase, and an acceleration phase. From roadway excavation to the occurrence of significant deformation and instability in deep, weak coal and rock, it generally takes 150 to 180 days or more, sometimes even longer than a year. Currently, in engineering, the stability of coal and rock deformation is judged by measuring the surface deformation of the roadway using the string line method and comparing it with a determined critical allowable value. However, if the measuring points are located close to the excavation face, i.e., the roadway has been excavated for a short period of time (generally no more than 10 days), the excavation process, such as shotcreting and rock loading, has a significant impact on the deformation observation at the measuring point location. It is difficult to observe the early deformation of coal and rock in the roadway, and the measured value of coal and rock deformation is significantly lower than the actual value. At the same time, because the time required for coal and rock deformation to reach the critical allowable value is long, the roadway has already become unstable when the deformation reaches the allowable critical value, and only rework can maintain the stability of coal and rock deformation.

[0003] The rapid deceleration phase of coal and rock deformation is relatively short, generally not exceeding 20 days. If the tendency for coal and rock deformation to become unstable can be identified shortly after the rapid deceleration phase ends, appropriate support can be selected in advance to maintain the stability of the coal and rock deformation, avoiding the significant increase in support costs, significant reduction in tunneling efficiency, and safety issues caused by the later-stage instability of weak coal and rock. In related technologies, the classification of deep roadway stability is mainly based on the stability of the surrounding rock. The characteristics of the surrounding rock are determined by physical and mechanical experiments and visual inspection, thereby determining the stability of the roadway. However, under the conditions of high ground stress, high ground temperature, high osmotic pressure, and strong mining disturbance in deep environments, the anisotropy of the rock is obvious, and the lithology changes significantly. Therefore, the method of judging roadway stability by physical and mechanical experiments and visual inspection of the surrounding rock has certain limitations. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a method for controlling the stability of deep roadways. This method, through refined analysis and classification of the causes of anchoring failure, clarifies the influence of the surrounding rock on the anchoring force. It facilitates the development of specific control methods for specific roadway lithology and anchoring agent distribution patterns, overcoming the limitations of methods that rely on physical and mechanical experiments and visual inspection of the surrounding rock to determine roadway stability.

[0005] The method for controlling the stability of deep roadways according to embodiments of the present invention includes:

[0006] S1. Select multiple testing locations within the roadway to be tested. At each testing location, test the anchoring force of at least one anchor cable to determine whether the anchoring force of the anchor cable at the testing location meets the design requirements.

[0007] S2. Further testing is conducted on anchor cables whose anchoring force does not meet the design requirements. The cause of anchoring failure is determined based on the test results. The cause of anchoring failure is classified into four categories: anchoring hole cannot be formed, no anchoring agent, poor annular distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage inside the surrounding rock.

[0008] S3. Take out at least one anchor body at the detection location, test the anchor body, and analyze and determine the cause of anchor failure based on the test results. The cause of anchor failure is divided into four categories: anchor hole cannot be formed, no anchoring agent, poor ring distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage inside the surrounding rock.

[0009] S4. Combining the causes of anchoring failure determined by the detection and analysis of the anchor cables and the causes of anchoring failure determined by the detection and analysis of the anchor bodies, analyze and determine the causes affecting the stability of the roadway. For the causes of failure such as the inability to form anchor holes, lack of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage occurring inside the surrounding rock, strengthen the interior of the surrounding rock and the anchoring interface by pumping in anchoring agent. For the cause of failure such as poor annular distribution of anchoring agent, optimize the annular distribution of anchoring agent by pumping in anchoring agent.

[0010] The deep roadway stability control method of this invention provides a detailed analysis and classification of the causes of anchoring failure, clarifies the influence of surrounding rock and anchoring agent on anchoring force, and is conducive to proposing specific control methods for specific roadway lithology and anchoring agent distribution patterns. It makes up for the limitations of the method of judging roadway stability by conducting physical and mechanical experiments on surrounding rock and visual inspection.

[0011] In some embodiments, multiple detection locations are distributed at different layers and orientations of the roadway to be detected, so as to ensure that anchor cables and anchor bodies under different lithological conditions in the roadway to be detected can be selected.

[0012] In some embodiments, the step of detecting the anchoring force of the anchor cable includes:

[0013] Clean the surface of the tunnel to ensure there is no debris or loose rocks;

[0014] Tension is applied to the anchor cable using a pulling device, and the tension value and displacement are recorded.

[0015] Based on the changes in tension and displacement, the anchoring force of the anchor cable is analyzed. If the tension decreases rapidly or the displacement increases sharply, the anchor cable has no anchoring force and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is lower than the design anchoring force, the anchoring force of the anchor cable is insufficient and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is not lower than the design anchoring force, the anchoring force of the anchor cable meets the design requirements.

[0016] In some embodiments, during the loading process, changes in the roadway surface are observed, and if unstable phenomena such as cracks or spalling occur, the test is stopped immediately.

[0017] In some embodiments, further testing is performed on anchor cables whose anchoring force does not meet design requirements, and the steps to analyze and determine the cause of anchoring failure based on the test results include:

[0018] The anchor cable is pulled out of the surrounding rock by applying tension through a pulling device until the anchor cable is completely pulled out of the surrounding rock.

[0019] If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchor hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor ring distribution of the anchoring agent.

[0020] Anchoring agent is placed into the anchoring hole, and the anchoring agent is pushed into the anchoring hole using the anchoring cable. If the resistance is too great when pushing, it is considered that the anchoring failure is due to the inability of the anchoring hole to be formed.

[0021] In some embodiments, the steps of detecting the anchor body and analyzing and determining the cause of anchor failure based on the detection results include:

[0022] The lithology of the rock in the anchor body is tested. If the rock is broken, has well-developed joints, and has low strength, the anchor failure is considered to be due to the inability to form the anchor hole.

[0023] The rock and anchoring agent of the anchor body are peeled off sequentially. The bonding state between the rock and the anchoring agent and the bonding state between the anchoring agent and the anchor cable are observed. The actual distribution pattern of the anchoring agent is also observed. If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchoring hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor annular distribution of the anchoring agent.

[0024] In some embodiments, the step of removing the anchor body includes:

[0025] Install the casing on the drilling rig and adjust the incident angle according to the laying angle of the anchor cable;

[0026] Start the drilling rig to drive the casing for core drilling, and at the same time start the mud pump to pump mud to protect the wall and remove slag;

[0027] After the entire length of the anchor body has entered the casing, the drilling rig and mud pump are shut off, and then the casing and anchor body are pulled out together.

[0028] In some embodiments, the deep tunnel stability classification and control method further includes adding a reinforcing anchor cable near the anchor cable whose anchoring force meets the design requirements.

[0029] In some embodiments, the reinforcing anchor cable is an ultra-high prestressed constant resistance high elongation anchor cable. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a deep roadway stability control method according to an embodiment of the present invention.

[0031] Figure 2 This is a flowchart of the deep roadway stability control method according to an embodiment of the present invention. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0033] The following describes a method for controlling the stability of deep tunnels according to an embodiment of the present invention, with reference to the accompanying drawings.

[0034] like Figure 1 As shown, the deep roadway stability control method of this invention includes:

[0035] S1. Select multiple testing locations within the roadway to be tested. At each testing location, test the anchoring force of at least one anchor cable to determine whether the anchoring force of the anchor cable at the testing location meets the design requirements.

[0036] It should be noted that by testing the anchoring force of the anchor cables (e.g., pull-out test, ultrasonic testing), and classifying the anchor cables into two categories based on whether their anchoring force meets the design requirements, those that do not are not further tested. Only those anchor cables whose anchoring force does not meet the design requirements are further tested to analyze and determine the cause of their failure, thus reducing the time and workload of testing roadway stability.

[0037] S2. Further testing is conducted on anchor cables whose anchoring force does not meet the design requirements. The cause of anchoring failure is determined based on the test results. The causes of anchoring failure are classified into four categories: anchor hole cannot be formed, no anchoring agent, poor annular distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage inside the surrounding rock.

[0038] It should be noted that by conducting further testing on anchor cables whose anchoring force does not meet the design requirements to analyze the causes of anchoring failure and classify the causes of anchoring failure, it is easier to propose corresponding control methods for specific causes of failure.

[0039] S3. Take out at least one anchor body at the test location, test the anchor body, and analyze and determine the cause of anchor failure based on the test results. The causes of anchor failure are classified into four categories: anchor hole cannot be formed, no anchoring agent, poor annular distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage inside the surrounding rock.

[0040] It should be noted that removing the anchor body allows for observation of the true distribution of the anchoring agent, avoiding damage to the anchor body and changes from its original state during anchor cable testing, thereby increasing the reliability of determining the cause of anchor failure.

[0041] S4. Combining the causes of anchoring failure determined by the detection and analysis of the anchor cables and the causes of anchoring failure determined by the detection and analysis of the anchor bodies, analyze and determine the causes affecting the stability of the roadway. For the causes of failure such as the inability to form anchor holes, lack of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage occurring inside the surrounding rock, strengthen the interior of the surrounding rock and the anchoring interface by pumping in anchoring agent. For the cause of failure such as poor annular distribution of anchoring agent, optimize the annular distribution of anchoring agent by pumping in anchoring agent.

[0042] It should be noted that by combining the causes of failure obtained from further testing of anchor cables whose anchoring force does not meet the design requirements with the causes of anchoring failure obtained from testing the anchor body, the probability of misjudgment is reduced.

[0043] The deep roadway stability control method of this invention provides a detailed analysis and classification of the causes of anchoring failure, clarifies the influence of surrounding rock and anchoring agent on anchoring force, and is conducive to proposing specific control methods for specific roadway lithology and anchoring agent distribution patterns. It makes up for the limitations of the method of judging roadway stability by conducting physical and mechanical experiments on surrounding rock and visual inspection.

[0044] In some embodiments, multiple detection locations are distributed at different layers and orientations of the roadway to be detected, so as to ensure that anchor cables and anchor bodies under different lithological conditions in the roadway to be detected can be selected.

[0045] It should be noted that, since the rocks in the tunnel have similar appearances, it is difficult to distinguish the lithology of rocks in different locations by appearance alone. Judgment can only be made during the construction of the rocks. Therefore, by distributing multiple detection points at different layers and orientations in the tunnel to be tested, it can be ensured that anchor cables and anchor bodies under different lithological conditions in the tunnel to be tested can be selected, thereby improving the accuracy and reliability of the detection results.

[0046] like Figure 2 As shown, in some embodiments, the step of detecting the anchoring force of the anchor cable includes:

[0047] Clean the surface of the tunnel to ensure there is no debris or loose rocks;

[0048] Tension is applied to the anchor cable using a pulling device, and the tension value and displacement are recorded.

[0049] Based on the changes in tension and displacement, the anchoring force of the anchor cable is analyzed. If the tension decreases rapidly or the displacement increases sharply, the anchor cable has no anchoring force and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is lower than the design anchoring force, the anchoring force of the anchor cable is insufficient and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is not lower than the design anchoring force, the anchoring force of the anchor cable meets the design requirements.

[0050] Furthermore, during the loading process, observe the changes on the surface of the tunnel. If unstable phenomena such as cracks or spalling occur, stop the test immediately.

[0051] Understandably, by pulling on the anchor cables and analyzing the changes in tension and displacement, anchor cables whose anchoring force does not meet the design requirements can be screened out. Only for anchor cables whose anchoring force does not meet the design requirements are further tested to analyze and determine the cause of failure, thus reducing the time and workload of testing roadway stability.

[0052] like Figure 2 As shown, in some embodiments, further testing is performed on anchor cables whose anchoring force does not meet design requirements. Based on the test results, the steps to analyze and determine the cause of anchoring failure include:

[0053] The anchor cable is pulled out of the surrounding rock by applying tension through a pulling device until the anchor cable is completely pulled out of the surrounding rock.

[0054] If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchor hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor ring distribution of the anchoring agent.

[0055] Anchoring agent is placed into the anchoring hole, and the anchoring agent is pushed into the anchoring hole using the anchoring cable. If the resistance is too great when pushing, it is considered that the anchoring failure is due to the inability of the anchoring hole to be formed.

[0056] Understandably, by fully pulling out the anchor cable and analyzing the distribution of the anchoring agent on the cable and the resistance when pushing the anchoring agent, it is easier to classify the causes of anchor failure, thereby facilitating the development of corresponding control methods for specific causes of failure.

[0057] like Figure 2 As shown, in some embodiments, the steps of detecting the anchor body and analyzing and determining the cause of anchor failure based on the detection results include:

[0058] The lithology of the rock used to anchor the object is tested. If the rock is broken, has well-developed joints, and has low strength, the anchoring failure is considered to be due to the inability to form the anchoring hole.

[0059] Sequentially peel off the rock and anchoring agent from the anchor body, observe the bonding state between the rock and the anchoring agent and between the anchoring agent and the anchor cable, and observe the actual distribution pattern of the anchoring agent. If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchoring hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor ring distribution of the anchoring agent.

[0060] Understandably, removing the anchor body allows for observation of the true distribution of the anchoring agent, avoiding damage to the anchor body and changes from its original state during anchor cable testing, thereby increasing the reliability of determining the cause of anchor failure.

[0061] In some embodiments, the step of removing the anchor body includes:

[0062] Install the casing on the drilling rig and adjust the incident angle according to the laying angle of the anchor cable;

[0063] Start the drilling rig to drive the casing for core drilling, and at the same time start the mud pump to pump mud to protect the wall and remove slag;

[0064] After the entire length of the anchor body has entered the casing, the drilling rig and mud pump are shut off, and then the casing and anchor body are pulled out together.

[0065] like Figure 2 As shown, in some embodiments, the deep roadway stability classification and control method further includes adding a reinforcing anchor cable near the anchor cable whose anchoring force meets the design requirements.

[0066] Specifically, the reinforcing anchor cable is an ultra-high prestressed constant resistance high elongation anchor cable.

[0067] It should be noted that, due to the deformation of deep tunnels during the excavation process, the anchor cables that currently meet the design requirements are insufficient to provide effective anchoring force to the surrounding rock after the tunnel deforms. Therefore, by adding reinforcing anchor cables, the surrounding rock is strengthened to improve the stability of the tunnel.

[0068] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0072] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0073] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A method for controlling the stability of deep roadways, characterized in that, include: S1. Select multiple testing locations within the roadway to be tested. At each testing location, perform a pull-out test on at least one anchor cable to test the anchoring force of the anchor cable, thereby determining whether the anchoring force of the anchor cable at the testing location meets the design requirements. S2. For anchor cables whose anchoring force does not meet the design requirements, pull them out of the surrounding rock, observe the pulled-out anchor cables, and analyze and determine the cause of anchoring failure based on the observation results. The cause of anchoring failure is divided into four categories: anchor hole cannot be formed, no anchoring agent, poor annular distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage inside the surrounding rock. S3. At least one anchor body at the detection location is extracted by core drilling, the lithology of the rock of the anchor body is detected, and the rock and anchoring agent of the anchor body are sequentially peeled off. The cause of anchor failure is determined by analyzing the test results. The cause of anchor failure is divided into four categories: anchor hole cannot be formed, no anchoring agent, poor ring distribution of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent or slippage inside the surrounding rock. S4. Combining the causes of anchoring failure determined by the detection and analysis of the anchor cables and the causes of anchoring failure determined by the detection and analysis of the anchor bodies, analyze and determine the causes affecting the stability of the roadway. For the causes of failure such as the inability to form anchor holes, lack of anchoring agent, slippage at the interface between the surrounding rock and the anchoring agent, or slippage occurring inside the surrounding rock, strengthen the interior of the surrounding rock and the anchoring interface by pumping in anchoring agent. For the cause of failure such as poor annular distribution of anchoring agent, optimize the annular distribution of anchoring agent by pumping in anchoring agent.

2. The method for controlling the stability of deep roadways according to claim 1, characterized in that, Multiple detection locations are distributed at different layers and orientations of the roadway to be tested, to ensure that anchor cables and anchor bodies under different lithological conditions in the roadway to be tested can be selected.

3. The method for controlling the stability of deep roadways according to claim 1, characterized in that, The steps for testing the anchoring force of anchor cables include: Clean the surface of the tunnel to ensure there is no debris or loose rocks; Tension is applied to the anchor cable using a pulling device, and the tension value and displacement are recorded. Based on the changes in tension and displacement, the anchoring force of the anchor cable is analyzed. If the tension decreases rapidly or the displacement increases sharply, the anchor cable has no anchoring force and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is lower than the design anchoring force, the anchoring force of the anchor cable is insufficient and does not meet the design requirements. If the displacement changes tend to stabilize and the tension is not lower than the design anchoring force, the anchoring force of the anchor cable meets the design requirements.

4. The method for controlling the stability of deep roadways according to claim 3, characterized in that, During the loading process, observe the changes on the surface of the tunnel. If instability occurs, stop the test immediately.

5. The method for controlling the stability of deep roadways according to claim 1, characterized in that, Further testing is conducted on anchor cables whose anchoring force does not meet design requirements. Based on the test results, the steps to analyze and determine the cause of anchoring failure include: The anchor cable is pulled out of the surrounding rock by applying tension through a pulling device until the anchor cable is completely pulled out of the surrounding rock. If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchor hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor ring distribution of the anchoring agent. Place the anchoring agent into the anchoring hole and use the anchor cable to push the anchoring agent into the anchoring hole. If the resistance is too great when pushing, it is considered that the anchoring failure is due to the inability of the anchoring hole to be formed.

6. The method for controlling the stability of deep roadways according to claim 1, characterized in that, The steps of testing the anchor body and analyzing and determining the cause of anchor failure based on the test results include: The lithology of the rock used to anchor the object is tested. If the rock is broken, has well-developed joints, and has low strength, the anchoring failure is considered to be due to the inability to form the anchoring hole. The rock and anchoring agent of the anchor body are peeled off sequentially. The bonding state between the rock and the anchoring agent and the bonding state between the anchoring agent and the anchor cable are observed. The actual distribution pattern of the anchoring agent is also observed. If no anchoring agent is found on the anchor cable, the anchoring failure is considered to be due to the absence of anchoring agent. If the total amount of anchoring agent bonded to the anchor cable is approximately equal to the amount of anchoring agent placed in the anchoring hole, the anchoring failure is considered to be due to slippage at the interface between the surrounding rock and the anchoring agent or slippage within the surrounding rock. If the adhesion pattern of the anchoring agent on the anchor cable is poor, the anchoring failure is considered to be due to poor annular distribution of the anchoring agent.

7. The method for controlling the stability of deep roadways according to claim 1, characterized in that, The steps for removing the anchor body include: Install the casing on the drilling rig and adjust the incident angle according to the laying angle of the anchor cable; Start the drilling rig to drive the casing for core drilling, and at the same time start the mud pump to pump mud to protect the wall and remove slag. After the entire length of the anchor body has entered the casing, the drilling rig and mud pump are shut off, and then the casing and anchor body are pulled out together.

8. The method for controlling the stability of deep roadways according to claim 1, characterized in that, It also includes adding reinforcing anchor cables near anchor cables whose anchoring force meets the design requirements.

9. The method for controlling the stability of deep roadways according to claim 8, characterized in that, The reinforcing anchor cable is an ultra-high prestressed constant resistance high extension anchor cable.

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