Methods for determining, warning, and supporting the stability of surrounding rock

Abstract

This invention discloses a method for determining, warning, and supporting the stability of surrounding rock. The process of installing anchor bolts includes the following steps: after the tunneling machine excavates the roadway and completes each excavation advance; the drilling rig drills a first borehole in the roof, and a detection device analyzes the drilling parameters during the drilling process in real time; when the detection device analyzes that the drilling parameters have not reached the critical value of separation, anchor bolts are installed at the set distance between the anchor bolt support and the excavation face; when the detection device analyzes that the drilling parameters have reached the critical value of separation, the roof in the drilling area is determined to be an unstable roof, and anchor bolts are installed in the first borehole; during at least two subsequent excavations and support operations on the unstable roof, the unsupported roof distance is reduced, and a second borehole is drilled. If the drilling parameters are found to still exceed the critical value of separation, additional anchor cables are installed; until the drilling parameters of the second borehole are continuously less than the critical value of separation, anchor cables are not installed; until the drilling parameters of the first borehole are continuously less than the critical value of separation, the unsupported roof distance is extended.

Description

Technical Field

[0001] This invention relates to the field of tunnel-related technologies, specifically to a method for determining, warning, and supporting the stability of surrounding rock. Background Technology

[0002] As tunnels are excavated, the surrounding rock deforms and deteriorates under ground stress, causing roof delamination. Roof delamination during tunneling is a major cause of roof collapse accidents in coal mines. Timely monitoring and taking measures to address roof delamination are crucial for ensuring safe tunnel excavation and are also requirements for intelligent coal mine construction. Currently, related technologies typically rely on the experience of construction workers to determine the existence and extent of roof delamination. However, this approach suffers from low accuracy and cannot effectively guarantee the stability of the surrounding rock. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention propose a method for determining, warning, and supporting the stability of surrounding rock. This method has the advantages of high accuracy in determining the stability of surrounding rock and effectively ensuring its stability.

[0005] According to the rock stability determination, early warning, and support method of the present invention, the process of installing anchor bolts includes the following steps: after the tunneling machine excavates the roadway and completes each excavation advance; the drilling rig drills a first borehole in the roof, and the detection device monitors the drilling parameters during the drilling process in real time and performs intelligent analysis; when the detection device analyzes that the drilling parameters have not reached the separation critical value, anchor bolts are installed according to the set anchor bolt support distance from the excavation face; when the detection device analyzes that the drilling parameters have reached the separation critical value, the roof in the drilling area is determined to be an unstable roof, an early warning is issued, and anchor bolts are installed in the first borehole; during the subsequent excavation and support processes of the unstable roof, the unsupported roof distance is reduced, and a second borehole is drilled for measurement. If the drilling parameters are found to still exceed the separation critical value, additional anchor cables are installed; until the drilling parameters of the second borehole are continuously less than the separation critical value, anchor cables are not installed; until the drilling parameters of the first borehole are continuously less than the separation critical value, the unsupported roof distance is extended.

[0006] According to the surrounding rock stability determination, early warning and support method of the present invention, when drilling the first borehole and the second borehole, the detection device determines the stability of the roof by detecting the drilling parameters, that is, determines whether the roof delamination occurs and the degree of delamination. In this way, the subjective judgment of the construction personnel is transformed into the objective judgment of the instrument, which improves the accuracy of the judgment result.

[0007] When the area where the first and second boreholes are located has an unstable roof, anchor bolts are immediately installed in the first borehole and anchor cables are installed in the second borehole. This timely reinforcement and support of the surrounding rock effectively ensures its stability and reduces the risks associated with subsequent operations.

[0008] In some embodiments, the process of later installing additional anchor cables includes the following steps: the drilling rig drills a second borehole in the top plate; when the detection device analyzes that the drilling parameters have not reached the separation critical value, anchor cables are installed according to the set distance between the reinforcement anchor cable support and the excavation face; when the detection device analyzes that the drilling parameters have reached the separation critical value, the top plate is determined to be an unstable top plate, an early warning is issued, the distance between the second borehole for reinforcement support and the excavation face is reduced, and anchor cables are installed in the second borehole until the drilling parameters are continuously less than the separation critical value for at least two times, at which point the set distance between the reinforcement anchor cable support and the excavation face is restored.

[0009] In some embodiments, the drilling parameters include at least one of the following: rig thrust, feed rate, drill rod torque, drill rod rotation speed, drill rod feed distance, and water pressure and water flow rate. When the drill bit passes through the delamination zone, the rig thrust decreases sharply, the drill rod torque decreases sharply, the drill rod rotation speed increases sharply to its rotation speed in the air, the drill rod feed rate increases sharply, the water pressure drops sharply, and the water flow rate increases sharply. The detection device identifies the delamination zone accordingly.

[0010] In some embodiments, the detection device includes a sensor assembly for measuring the drilling parameters and a data intelligent analysis system, the sensor assembly and the data intelligent analysis system being connected; after detecting the drilling parameters during drilling, the sensor assembly transmits the drilling parameters to the data intelligent analysis system; the data intelligent analysis system analyzes and calculates the drilling parameters, and compares the calculation results of the drilling parameters with the separation critical value to determine the state of the roof; the data intelligent analysis system also determines the separation location and separation opening of the unstable roof based on the calculation results of the drilling parameters.

[0011] In some embodiments, the rate of change of drill pipe advance distance, drill pipe torque, and drill pipe rotation speed constitutes the first characteristic value; the rate of change of water pressure and water flow rate constitutes the second characteristic value; the data intelligent analysis system determines the separation position and separation opening based on the calculation results of the first and second characteristic values ​​by comprehensively analyzing and calculating the first and second characteristic values.

[0012] In some embodiments, when the drilling rig drills the first hole / second hole, if the drilling parameters measured in at least two of the first hole / second hole are greater than the separation critical value, the top plate where the drilling area is located is determined to be an unstable top plate.

[0013] In some embodiments, when the drilling rig drills the first borehole / second borehole, if the delamination position measured in at least two of the first boreholes / second boreholes is within 0 to 1.2 m of the tail of the anchor bolt / anchor cable, then the anchor bolt and anchor cable shall adopt any one of the following anchoring methods: extended anchoring, full-length anchoring, or pressurized anchoring.

[0014] In some embodiments, once all anchor bolts and anchor cables are installed, the detection device automatically connects and generates a three-dimensional digital model of the roadway containing the fracture field based on the cracks detected within the distribution range of the anchor bolts and anchor cables.

[0015] In some embodiments, the length of the excavation advance ranges from 800 mm to 1500 mm; the distance between the anchor bolts adjacent to the excavation face and the excavation face includes several excavation advances, ranging from 0.3 m to 20 m; the selection of the distance between the anchor bolts adjacent to the excavation face and the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face.

[0016] In some embodiments, the distance between the anchor cable and the excavation face adjacent to the excavation face includes several excavation advances, ranging from 2m to 20m; the selection of the distance between the anchor bolt and the excavation face adjacent to the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a roadway for a method of determining, warning, and supporting the surrounding rock stability according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of a drilling rig entering a delamination layer in a method for determining, warning, and supporting surrounding rock stability according to an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of a drilling rig exiting the rock separation layer in the method for determining, warning, and supporting the surrounding rock stability according to an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the critical value of roadway roof delamination in the method for determining, warning and supporting the surrounding rock stability according to an embodiment of the present invention.

[0021] Figure 5 This is a flowchart of the detection device and drilling parameters of the surrounding rock stability determination, early warning and support method according to an embodiment of the present invention.

[0022] Reference numerals in the attached drawings: 1. First borehole; 2. Second borehole; 3. Delamination; 4. Torque sensor; 5. Thrust sensor; 6. Displacement sensor; 7. Drilling rig. Detailed Implementation

[0023] 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.

[0024] The following is combined with Figures 1-5 A method for determining, warning, and supporting surrounding rock stability according to an embodiment of the present invention is described.

[0025] like Figures 1-3 As shown, according to the rock stability determination, early warning, and support method of this invention, the process of installing anchor bolts includes the following steps: After the tunneling machine excavates the roadway and completes each excavation advance, the drilling rig 7 drills a first borehole 1 in the roof. The detection device monitors the drilling parameters of the drilling rig 7 in real time during the drilling process and performs intelligent analysis. When the detection device analyzes that the drilling parameters have not reached the critical value for separation, the anchor bolts are installed according to the set distance between the anchor bolt support and the excavation face. When the detection device analyzes that the drilling parameters have reached the critical value for separation, it determines that the roof in the drilling area is an unstable roof, issues an early warning, and installs anchor bolts in the first borehole 1.

[0026] During at least two subsequent excavations and support operations on the unstable roof, the unsupported roof distance should be reduced, and a second borehole 2 should be drilled for measurement. If the drilling parameters are still found to exceed the critical value for separation, additional anchor cables should be installed. Anchor cables should not be installed until the drilling parameters of the second borehole 2 are consistently lower than the critical value for separation. The unsupported roof distance should be extended until the drilling parameters of the first borehole 1 are consistently lower than the critical value for separation.

[0027] According to the surrounding rock stability determination, early warning and support method of the present invention, when drilling the first borehole 1 and the second borehole 2, the detection device determines the stability of the roof by detecting the drilling parameters, that is, determines whether the roof has delamination 3 and the degree of delamination. Thus, the subjective judgment of the construction personnel is transformed into the objective judgment of the instrument, which improves the accuracy of the judgment result.

[0028] When the area where the first borehole 1 and the second borehole 2 are located is an unstable roof, anchor bolts are immediately installed in the first borehole 1 and anchor cables are installed in the second borehole 2. This timely reinforcement and support of the surrounding rock effectively ensures its stability and reduces the risks associated with subsequent operations.

[0029] Understandably, the first borehole 1 is used both to determine the stability of the roof slab and to install anchor bolts. The second borehole 2 is used both to determine the stability of the roof slab and to install anchor cables.

[0030] In some embodiments, such as Figures 1-3 As shown, the subsequent process of installing additional anchor cables includes the following steps: Drilling rig 7 drills a second borehole 2 in the top plate. When the detection device analyzes that the drilling parameters have not reached the critical value for separation, anchor cables are installed according to the set distance between the reinforcement anchor cable support and the excavation face.

[0031] When the detection device analyzes the drilling parameters and they reach the critical value of separation, it determines that the roof is an unstable roof and issues an early warning. It then reduces the distance between the second borehole 2 of the reinforcement support and the excavation face, and installs anchor cables in the second borehole 2 until the drilling parameters are continuously less than the critical value of separation for at least two consecutive times. At this point, it restores the set distance between the reinforcement anchor cable support and the excavation face.

[0032] Therefore, during the later stages of anchor cable installation, when the detection device determines that the roof is unstable, the distribution of the second borehole 2 / anchor bolt in the unstable roof area should be changed, i.e., the distance between the second borehole 2 for reinforcement and the excavation face should be reduced. In other words, to ensure the stability of the surrounding rock in the unstable roof area, it is necessary to reinforce and strengthen the surrounding rock in the unstable roof area. As a result, the distribution density of anchor cables in this area can be set higher, thereby improving the safety factor for workers during construction.

[0033] In some embodiments, such as Figures 1-3 As shown, the drilling parameters include at least one of the following: drilling rig thrust, feed rate, drill rod torque, drill rod rotation speed, drill rod feed distance, water pressure, and water flow rate. When the drill bit passes through the separation layer 3, the drilling rig thrust decreases sharply, the drill rod torque decreases sharply, the drill rod rotation speed increases sharply to its rotation speed in the air, the drill rod feed rate increases sharply, the water pressure drops sharply, and the water flow rate increases sharply. The detection device identifies the separation layer 3 accordingly.

[0034] In addition, the detection device can identify the location and opening of the separation layer 3 based on the thrust of the drilling rig 7, the torque of the drill rod, the rotation speed of the drill rod, the advance speed, the advance distance of the drill rod, as well as the sudden changes and magnitudes of water pressure and water flow. This further improves the reliability and accuracy of the detection results.

[0035] It should be noted that when the drill bit of the drilling rig 7 is drilling the first borehole 1 / second borehole 2, water needs to be added to the drill bit to cool it down, and the water pressure and water flow rate mentioned above are the water pressure and water flow rate of the water source used to cool the drill bit.

[0036] Specifically, the parameters while drilling include rig thrust, feed rate, drill pipe torque, drill pipe rotation speed, drill pipe feed distance, water pressure, and water flow rate.

[0037] Specifically, the detection device includes a thrust sensor 5, a speed sensor, a torque sensor 4, a rotational speed sensor, a displacement sensor 6, a water pressure sensor, and a water flow sensor. The thrust sensor 5 measures the thrust of the drilling rig 7, the speed sensor measures the advance speed of the drilling rig 7, the torque sensor 4 measures the drill rod torque, the rotational speed sensor measures the drill rod rotational speed, the displacement sensor 6 measures the drill rod advance distance, the water pressure sensor measures the water pressure, and the water flow sensor measures the water flow rate.

[0038] In some embodiments, such as Figure 1 , Figure 4 and Figure 5 As shown, the detection device includes a sensor assembly for measuring drilling parameters and a data intelligent analysis system, which are connected together. The sensor assembly detects the drilling parameters during drilling and transmits them to the data intelligent analysis system. The data intelligent analysis system analyzes and calculates the drilling parameters, comparing the calculated results with the separation threshold to determine the roof condition. Based on the calculated drilling parameters, the data intelligent analysis system also determines the separation 3 location and separation 3 opening of the unstable roof.

[0039] Therefore, the data intelligent analysis system, through the calculation of drilling parameters, achieved the measurement of the location and opening of the third separation layer in the unstable roof. This essentially realizes both qualitative and quantitative analysis of the third separation layer in the unstable roof, thereby further improving the accuracy and reliability of the detection results.

[0040] It should be noted that the data intelligent analysis system establishes a functional relationship between the calculation results of the drilling parameters, the critical value of the separation, and the separation 3 opening. This functional relationship allows the determination of the separation 3 opening value from the determined values ​​of the aforementioned calculation results.

[0041] Specifically, the data intelligent analysis system uses neural network algorithms, correction algorithms, and related weight matrices to improve the processing effect of drilling parameters.

[0042] In some embodiments, such as Figure 1 As shown, the rates of change of drill pipe advance distance, drill pipe torque, and drill pipe rotation speed constitute the first characteristic value. The rates of change of water pressure and water flow rate constitute the second characteristic value. The data intelligent analysis system determines the location and opening degree of separation layer 3 based on the calculation results of the first and second characteristic values ​​through comprehensive analysis and calculation of the first and second characteristic values.

[0043] In other words, the rates of change of drill pipe advance distance, drill pipe torque, and drill pipe rotation speed form a first matrix, from which the first eigenvalue is derived. The rates of change of water pressure and water flow rate form a second matrix, from which the second eigenvalue is derived. The data intelligent analysis system performs function calculations on the first and second eigenvalues, and determines the location and opening degree of separation layer 3 based on the calculation results.

[0044] Therefore, the location and opening of the detachment layer 3 were further quantitatively analyzed, which improved the accuracy of the detection.

[0045] It should be noted that the above rate of change is the change of the drilling parameters per unit time.

[0046] In some embodiments, such as Figure 1 and Figure 4 As shown, when drilling the first borehole 1 / second borehole 2, if the drilling parameters measured in at least two of the first borehole 1 / second borehole 2 are greater than the separation critical value, the top plate where the drilling area is located is determined to be an unstable top plate.

[0047] This avoids misjudging the roof and ensures the reliability of the test results.

[0048] In some embodiments, such as Figures 1-3 As shown, when drilling the first borehole 1 / second borehole 2, if the location of the separation layer 3 measured in at least two of the first borehole 1 / second borehole 2 is within the range of 0 to 1.2m at the tail of the anchor rod / anchor cable, then the anchor rod and anchor cable shall adopt any one of the following anchoring methods: extended anchoring, full-length anchoring, or pressurized anchoring.

[0049] This ensures the anchoring effect of the anchor bolts / cables and guarantees the support effect for unstable roofs.

[0050] Understandably, the end of the anchor bolt / cable that extends into the surrounding rock mass is the aforementioned tail section. If a delamination 3 exists in the roof, the large area of ​​the delamination 3 void zone is detrimental to the support effect of the anchor bolt / cable. Therefore, anchor bolts and cables should adopt extended anchoring / full-length anchoring / pressure anchoring to improve the anchoring force of the anchor bolts and the reliability of the support.

[0051] In some embodiments, once all anchor bolts and anchor cables are installed, the detection device automatically connects and generates a three-dimensional digital model of the roadway containing the fracture field based on the cracks detected within the distribution range of the anchor bolts and anchor cables.

[0052] Therefore, the establishment of the three-dimensional digital model of this tunnel facilitates subsequent systematic analysis of the fracture field distribution area and the anchor bolt support method. Furthermore, simulation experiments can be conducted based on this three-dimensional digital model to determine the optimal distribution and support method of the anchor bolts. This further refines the methods for determining and supporting the surrounding rock stability.

[0053] Furthermore, constructing a fracture field allows for a more intuitive assessment of surrounding rock stability. By establishing a fracture field, the location of delamination can be identified, an instability model can be constructed, the instability mode can be predicted, and the pressure intensity can be determined. The fracture field data obtained from two consecutive monitoring sessions can be used to determine the rate of roof fracture, providing a basis for dynamic support.

[0054] To facilitate understanding, the selection process of the three-dimensional digital model of the tunnel will be explained in detail:

[0055] First, select two sets of supports (rock bolts and / or anchor cables) distributed on both sides of the fracture field along the roadway direction.

[0056] Each support group consists of multiple anchor bolts and / or anchor cables spaced apart along the width of the roadway.

[0057] The top and bottom ends of the anchor bolts and / or anchor cables form connection points, and multiple connection points are connected sequentially. Thus, the connecting lines formed by the connection points and the line segments of the anchor bolts and / or anchor cables can form a model similar to a cuboid, which is the three-dimensional digital model of the tunnel.

[0058] In some embodiments, the excavation advance length ranges from 800 mm to 1500 mm. The distance between the anchor bolts adjacent to the excavation face and the excavation face includes several excavation advances, ranging from 0.3 m to 20 m. The selection of the distance between the anchor bolts adjacent to the excavation face and the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face.

[0059] Specifically, when there is no unstable roof within multiple excavation advances adjacent to the excavation face, the distance between the anchor bolts and the excavation face can be chosen to be relatively long. However, when there is an unstable roof within multiple excavation advances adjacent to the excavation face, the unstable roof must first be supported. Since the unstable roof reduces the stability of the surrounding rock, the distance between the anchor bolts and the excavation face should be chosen to be relatively short in this case, so that the anchor bolts can achieve a good support effect for the surrounding rock.

[0060] Furthermore, if the roof slab within the excavation advance is a stable roof slab, then the number of anchor bolts used within that excavation advance shall not be less than 4, and the length of the anchor bolts shall be 2m to 3m.

[0061] In some embodiments, the distance between the anchor cable and the excavation face adjacent to the excavation face includes several excavation advances, ranging from 2m to 20m. The selection of the distance between the anchor cable and the excavation face adjacent to the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face.

[0062] Specifically, when there is no unstable roof within multiple excavation advances adjacent to the excavation face, the distance between the anchor cables and the excavation face can be chosen to be relatively long. However, when an unstable roof exists within multiple excavation advances adjacent to the excavation face, the unstable roof must first be supported. Since the unstable roof reduces the stability of the surrounding rock, the distance between the anchor cables and the excavation face should be chosen to be relatively short in this case, so that the anchor cables can achieve a good support effect for the surrounding rock.

[0063] Furthermore, if the roof slab within the excavation advance is a stable roof slab, then the number of anchor cables used within that excavation advance is 2 to 3, and the length of the anchor cables is 4m to 7m.

[0064] According to the surrounding rock stability determination, early warning, and support method of this invention, when the drill bit enters and exits the separation layer 3, the torque and rotation speed of the drill bit are monitored and recorded, and the rate of change of the drill bit torque and rotation speed are calculated. The width of the separation layer 3 is measured and calibrated by combining a large number of first boreholes 1 and / or second boreholes 2 in the unstable plate. The rate of change and abrupt change points of the torque and rotation speed when the drill bit enters and exits the separation layer 3 are obtained. The detection device calculates the drill rod advance length and total advance length based on the abrupt change points and an intelligent algorithm, and determines the position of the separation layer 3 based on the drill rod advance length and total advance length.

[0065] When the drill bit enters and exits the separation layer 3, the water pressure and water volume are monitored and recorded. By comparing the normal water pressure and water volume at the same time, it is determined whether the separation layer 3 exists and its size.

[0066] 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 are not intended to 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for determining, warning, and supporting the stability of surrounding rock, characterized in that, The process of installing anchor bolts includes the following steps: The tunnel boring machine excavates the tunnel and completes each excavation advance; The drilling rig drills the first hole in the top plate, and the detection device monitors the drilling parameters of the drilling rig in real time during the drilling process and performs intelligent analysis. When the detection device analyzes that the drilling parameters have not reached the critical value of separation, the anchor bolts are installed according to the set distance between the anchor bolt support and the excavation face. When the detection device analyzes the drilling parameters and they reach the critical value of separation, it determines that the top plate where the drilling area is located is an unstable top plate, issues an early warning, and installs anchor bolts in the first borehole. During at least two subsequent excavations and support operations of the unstable roof, the distance between the roof sections should be reduced, and a second borehole should be drilled for measurement. If the drilling parameters are found to still exceed the critical value for separation, additional anchor cables should be installed. When the drilling parameters of the second borehole remain below the critical value for separation, anchor cables are not installed. When the drilling parameters of the first borehole remain below the critical value for separation, the unsupported roof distance is extended. The process of installing additional anchor cables includes: The drilling rig drilled a second hole in the top slab; When the detection device analyzes that the drilling parameters have not reached the critical value of separation, the anchor cable is installed according to the set distance between the reinforcement anchor cable support and the excavation face. When the detection device analyzes the drilling parameters and they reach the critical value of separation, it determines that the roof is unstable and issues an early warning. It then reduces the distance between the second borehole for reinforcement support and the excavation face, and installs anchor cables in the second borehole until the drilling parameters are continuously less than the critical value of separation for at least two consecutive times. At this point, it restores the set distance between the reinforcement anchor cable support and the excavation face.

2. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, The drilling parameters include at least one of the following: rig thrust, feed rate, drill rod torque, drill rod rotation speed, drill rod feed distance, water pressure, and water flow rate. When the drill bit passes through the delamination zone, the rig thrust decreases sharply, the drill rod torque decreases sharply, the drill rod rotation speed increases sharply to its rotation speed in air, the drill rod feed rate increases sharply, the water pressure drops sharply, and the water flow rate increases sharply. The detection device identifies the delamination zone based on these parameters.

3. The method for determining, warning, and supporting surrounding rock stability according to claim 2, characterized in that, The detection device includes a sensor assembly for measuring the drilling parameters and a data intelligent analysis system, wherein the sensor assembly and the data intelligent analysis system are connected. After the sensor assembly detects the drilling parameters during drilling, it transmits the drilling parameters to the data intelligent analysis system. The data intelligent analysis system analyzes and calculates the drilling parameters, and compares the calculation results of the drilling parameters with the separation critical value to determine the state of the roof. The data intelligent analysis system also determines the delamination location and delamination opening of the unstable roof based on the calculation results of the drilling parameters.

4. The method for determining, warning, and supporting surrounding rock stability according to claim 3, characterized in that, The rate of change of drill pipe advance distance, drill pipe torque, and drill pipe rotation speed constitutes the first characteristic value; The rates of change of water pressure and water flow constitute the second characteristic value; The data intelligent analysis system determines the delamination location and delamination opening based on the comprehensive analysis and calculation of the first and second characteristic values.

5. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, When the drilling rig drills the first hole / second hole, if the drilling parameters measured in at least two of the first hole / second hole are greater than the separation critical value, the top plate where the drilling area is located is determined to be an unstable top plate.

6. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, When the drilling rig drills the first borehole / second borehole, if the delamination position measured in at least two of the first boreholes / second boreholes is within 0 to 1.2m of the tail of the anchor rod / anchor cable, then the anchor rod and anchor cable shall adopt any one of the following anchoring methods: extended anchoring, full-length anchoring, or pressurized anchoring.

7. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, Once all anchor bolts and cables are installed, the detection device automatically connects and generates a three-dimensional digital model of the tunnel containing the fracture field based on the cracks detected within the distribution range of the anchor bolts and cables.

8. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, The excavation advance length ranges from 800mm to 1500mm; The distance between the anchor bolts adjacent to the excavation face and the excavation face includes several excavation advances, ranging from 0.3m to 20m; The distance between the anchor bolts and the excavation face adjacent to the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face.

9. The method for determining, warning, and supporting surrounding rock stability according to claim 1, characterized in that, The distance between the anchor cable adjacent to the excavation face and the excavation face includes several excavation advances, ranging from 2m to 20m; The distance between the anchor bolts and the excavation face adjacent to the excavation face needs to be determined based on the presence or absence of an unstable roof and the distance between the unstable roof and the excavation face adjacent to the excavation face.

10. The method for determining, warning, and supporting surrounding rock stability according to claim 9, characterized in that, If the roof slab within the excavation advance is a stable roof slab, then the number of anchor cables used within that excavation advance is 2 to 3, and the length of the anchor cables is 4m to 7m.

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