Drilling stress monitoring method

Abstract

Disclosed is a drilling stress monitoring method. The method comprises the following steps: dividing an entire drill rod into a plurality of short sections to be tested, and mounting a stress measurement unit on each of said short sections; controlling, by means of a control unit, the stress measurement units to collect ground stresses applied to the surfaces of said short sections by a drilling surrounding rock in a drilling process of corresponding said short sections, so as to obtain several groups of stress measurement information, and uploading the several groups of stress measurement information to the control unit; the control unit separately importing the several groups of stress measurement information into a drilling stress monitoring model, so as to draw a plurality of groups of stress change amplitude curves; and monitoring stress change conditions of the drilling surrounding rock in a drilling construction process on the basis of the plurality of groups of stress change amplitude curves. Therefore, the change conditions of a ground stress of a drilling surrounding rock are observed in real time by means of the trends of stress change amplitude curves, and possible accidents caused by changes in the ground stress of the drilling surrounding rock are predicted and determined, thereby reducing potential safety hazards caused in the drilling construction process.

Description

A drilling stress monitoring method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 5, 2023, with application number 202311651660.1 and invention name “A Method for Monitoring Borehole Stress”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of mining safety detection technology, and in particular to a drilling stress monitoring method. Background Art

[0003] During routine coal mining operations, coal extraction inevitably causes a redistribution of the rock mass stress field. This new stress distribution has a significant impact on the stability of tunnels and stopes. Especially in deep mines, rock bursts, caused by the highly concentrated stress field in the surrounding rock, are common. Rock bursts are a dynamic phenomenon characterized by sudden, drastic, and violent destruction of the coal and rock mass surrounding mine tunnels and stopes due to the release of deformation energy. Essentially, it results from the sudden release of a large amount of elastic energy. Rock bursts are essentially stress issues within the coal and rock mass, and therefore, "stress" is the most reliable physical quantity for monitoring rock bursts. Borehole stress gauges are widely used in the art to monitor stress changes in the surrounding rock of mine tunnels. Existing borehole stress gauges typically utilize a hydraulic oil pillow structure, monitoring changes in surrounding rock stress by monitoring the pressure exerted by changes in ground pressure on the pillow. However, these gauges can only detect stress changes during monitoring, but cannot accurately monitor the source and direction of the stress, nor can they accurately determine potential accidents caused by stress changes.

[0004] Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a drilling stress monitoring method to solve the technical problems mentioned in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solutions:

[0007] A drilling stress monitoring method, comprising:

[0008] Step S1: Divide the drill pipe into multiple short sections to be tested, and install a stress detection unit on each of the short sections to be tested;

[0009] Step S2: connecting the stress detection units on multiple sections of the pup joints to be tested to a control unit respectively, wherein the control unit controls the stress detection units to collect the ground stress exerted on the surface of the pup joint by the surrounding rock of the borehole during the drilling process of the corresponding pup joint to be tested, obtains several sets of stress detection information, and uploads the several sets of stress detection information to the control unit;

[0010] Step S3: The control unit imports the plurality of sets of stress detection information into the drilling stress monitoring model, and draws a plurality of sets of stress change amplitude curves, wherein:

[0011] The drilling stress monitoring model is provided with a plurality of sub-models, each of which corresponds to each of the stress detection units, and is used to store the stress detection information uploaded by the corresponding stress detection unit, and to draw a stress change amplitude curve based on a plurality of continuous stress detection information within a certain time period;

[0012] Step S4: monitoring the stress changes of the surrounding rock of the borehole during the drilling construction process according to the multiple groups of stress change amplitude curves.

[0013] Optionally, in step S1, the stress detection unit includes four groups of stress acquisition modules evenly distributed along the circumference of the short section to be tested, and the four groups of stress acquisition modules are respectively used to collect the ground stress applied by the surrounding rock of the borehole on the surface of the short section to be tested along the four directions of east, west, south and north.

[0014] Optionally, in step S2, a monitoring period is set, and the control unit controls the four stress acquisition modules on each of the short subs to be tested to respectively collect the ground stresses exerted by the surrounding rock of the borehole on the surface of the short subs to be tested in the east, west, south, and north directions according to the monitoring period, to obtain four sets of stress detection information, and convert the four sets of stress detection information into digital signals and upload them to the control unit, wherein:

[0015] The stress acquisition module includes a stress acquisition sensor and a data processor. The stress acquisition sensor is used to collect the ground stress of the borehole surrounding rock, obtain the stress detection information, and send the stress detection information to the data processor to convert it into a digital signal and upload it to the control unit. The data processor is also used to receive the control instructions issued by the control unit and send the control instructions to the stress acquisition sensor to collect the ground stress of the borehole surrounding rock.

[0016] Optionally, in step S3, a stress monitoring coordinate system is provided in the sub-model, and the stress monitoring coordinate system is a plane coordinate axis arranged in a cross pattern, wherein:

[0017] The stress monitoring coordinate system uses a number of continuity test time nodes within a monitoring period as abscissas, and the values ​​of the several continuity test time nodes on the abscissas are symmetrically arranged with the origin of the stress monitoring coordinate system as the center;

[0018] The stress monitoring coordinate system uses a plurality of continuous borehole surrounding rock in-situ stress values ​​as ordinates, and the plurality of continuous borehole surrounding rock in-situ stress values ​​on the ordinates are symmetrically arranged with the origin of the stress monitoring coordinate system as the center;

[0019] The values ​​of several of the continuity test time nodes and the ground stress values ​​of several of the continuity borehole surrounding rocks are increased successively along the axis direction from the origin to form four sub-coordinate systems to draw stress change amplitude curves in four different monitoring directions.

[0020] Optionally, in step S3, the four sets of stress detection information collected on the same pup joint to be tested are respectively imported into the corresponding sub-models, and corresponding stress change amplitude curves are respectively drawn on the four sub-coordinate systems of the sub-model.

[0021] Optionally, in step S4, the in-situ stress values ​​of the surrounding rock of the borehole at the same test time node in the stress variation amplitude curve on the same sub-coordinate system in the multiple sub-models are used to monitor the in-situ stress values ​​of the surrounding rock of the borehole in the same monitoring direction for multiple sections of the short section to be tested; and the in-situ stress distribution of the surrounding rock of the borehole where the short section to be tested is located at different borehole depths is analyzed based on the in-situ stress values ​​of the surrounding rock of the borehole in the same monitoring direction for multiple sections of the short section to be tested;

[0022] According to the ground stress values ​​of the surrounding rock of the borehole at the same test time node in the stress change amplitude curves on the four sub-coordinate systems in each of the sub-models, the ground stress of the surrounding rock of the borehole along different monitoring directions of the corresponding short section to be tested is monitored, and according to the ground stress of the surrounding rock of the borehole along different monitoring directions of the short section to be tested, the ground stress distribution of the surrounding rock of the borehole around the short section to be tested is analyzed.

[0023] Optionally, an in-situ stress alarm threshold of the borehole surrounding rock is set, and the control unit controls the stress detection unit to obtain stress detection information on the corresponding short joint to be tested in real time. Then, based on the in-situ stress alarm threshold of the borehole surrounding rock and the current detection value of the in-situ stress in the stress detection information, it is determined whether the in-situ stress of the borehole surrounding rock on the corresponding short joint to be tested is close to the bearing range of the short joint to be tested, wherein:

[0024] If the in-situ stress alarm threshold of the borehole surrounding rock is greater than or equal to the current detected value of the in-situ stress in the stress detection information, then the in-situ stress of the borehole surrounding rock on the short joint to be tested is close to the pressure-bearing range of the short joint to be tested, and the control unit issues an alarm message to promptly remind the construction personnel. After the construction personnel eliminate the alarm message, the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short joint to be tested according to the monitoring period;

[0025] If the ground stress alarm threshold of the borehole surrounding rock is less than the current detection value of the ground stress in the stress detection information, the ground stress of the borehole surrounding rock on the short joint to be tested is lower than the bearing range of the short joint to be tested, and the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short joint to be tested according to the monitoring period.

[0026] Optionally, the control unit uses time as a reference axis and sequentially inputs the time determined by the recorded alarm information into the judgment module to obtain an alarm frequency with time as a reference, and determines whether the interval time between the alarm information tends to diverge or converge based on the interval value between the alarm frequencies, wherein:

[0027] If the intervals between alarm messages tend to diverge, it means that the current ground stress of the surrounding rock of the borehole triggers the alarm message due to temporary ground stress concentration caused by the vibration of the drill bit during the drilling process due to the hard stratum geology. The alarm message can be eliminated by the construction personnel to avoid misjudgment.

[0028] If the intervals between alarm messages tend to be concentrated, it means that the ground stress of the surrounding rock of the borehole continues to concentrate toward the inside of the borehole. It is necessary to suspend drilling construction and take corresponding support measures near the borehole.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] The borehole stress monitoring method provided in the present application, in order to accurately monitor the source direction of the ground stress of the borehole surrounding rock, collects the ground stress applied to the surface of the short section to be tested in the east, west, south and north directions of the borehole surrounding rock through four groups of stress acquisition modules evenly distributed along the circumference of the short section to be tested, and draws a stress change amplitude curve, so as to monitor the ground stress around the drill pipe through the stress change amplitude curve, and observe the ground stress change of the borehole surrounding rock in real time through the direction of the stress change amplitude curve, so as to predict and judge possible accidents caused by the change of ground stress of the borehole surrounding rock, and reduce the safety hazards caused by the drilling construction process.

[0031] Figures in the specification

[0032] The present application will be further described below with reference to the accompanying drawings:

[0033] FIG1 is a schematic flow chart of a drilling stress monitoring method of the present application;

[0034] FIG2 is a schematic diagram of a stress monitoring coordinate system in a drilling stress monitoring method of the present application. DETAILED DESCRIPTION

[0035] The following is a detailed description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments; based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work shall fall within the scope of protection of this application.

[0036] As shown in Figures 1 and 2, the present application provides a drilling stress monitoring method, comprising the following steps:

[0037] Step S1: Divide the drill pipe into multiple short sections to be tested, and install a stress detection unit on each short section to be tested.

[0038] In this embodiment, in order to accurately monitor the source direction of the ground stress of the borehole surrounding rock, the stress detection unit includes four groups of stress acquisition modules evenly distributed along the circumference of the short section to be tested. The four groups of stress acquisition modules are used to collect the ground stress applied to the surface of the short section to be tested in the east, west, south and north directions of the borehole surrounding rock. By monitoring the ground stress around the drill rod, the ground stress change of the borehole surrounding rock can be observed in real time, thereby predicting and judging possible accidents caused by the change of the ground stress of the borehole surrounding rock, and reducing the safety hazards caused by the drilling construction process.

[0039] Step S2: The stress detection units on the multiple sections of the short sections to be tested are connected to the control unit respectively. The control unit controls the stress detection units to collect the ground stress exerted on the surface of the short section to be tested by the surrounding rock of the borehole during the drilling process of the corresponding short section to be tested, obtains several sets of stress detection information, and uploads the several sets of stress detection information to the control unit.

[0040] Among them, the monitoring cycle is set, and the control unit controls the four stress acquisition modules on each short section to be tested to respectively collect the ground stress exerted on the surface of the short section to be tested by the surrounding rock of the borehole in the four directions of east, west, south and north according to the monitoring cycle, and obtain four sets of stress detection information. The four sets of stress detection information are converted into digital signals and uploaded to the control unit, wherein:

[0041] The stress acquisition module includes a stress acquisition sensor and a data processor. The stress acquisition sensor is used to collect the ground stress of the borehole surrounding rock, obtain stress detection information, and send the stress detection information to the data processor to convert it into a digital signal and upload it to the control unit. The data processor is also used to receive the control instructions issued by the control unit and send the control instructions to the stress acquisition sensor to collect the ground stress of the borehole surrounding rock.

[0042] Step S3: The control unit imports several sets of stress detection information into the drilling stress monitoring model, and draws multiple sets of stress change amplitude curves, where:

[0043] The drilling stress monitoring model is equipped with multiple sub-models, each of which corresponds to each stress detection unit. The sub-models are used to store the stress detection information uploaded by the corresponding stress detection unit and draw a stress change amplitude curve based on a number of continuous stress detection information within a certain time period.

[0044] In this embodiment, a stress monitoring coordinate system is set in the sub-model. The stress monitoring coordinate system is a plane coordinate axis arranged in a cross pattern, wherein:

[0045] The stress monitoring coordinate system uses a number of continuity test time nodes within the monitoring period as the horizontal coordinate, and the values ​​of the several continuity test time nodes on the horizontal coordinate are symmetrically arranged with the origin of the stress monitoring coordinate system as the center;

[0046] The stress monitoring coordinate system uses several continuous borehole surrounding rock stress values ​​as ordinates, and the several continuous borehole surrounding rock stress values ​​on the ordinates are symmetrically arranged with the origin of the stress monitoring coordinate system as the center;

[0047] The numerical values ​​of several continuous test time nodes and several continuous borehole surrounding rock stress values ​​are increased successively along the axis direction from the origin to form four sub-coordinate systems to draw stress change amplitude curves in four different monitoring directions.

[0048] Furthermore, the four sets of stress detection information collected on the same short joint to be tested are respectively imported into the corresponding sub-model, and the corresponding stress change amplitude curves are respectively drawn on the four sub-coordinate systems of the sub-model.

[0049] Step S4: monitoring stress changes of the surrounding rock during the drilling process according to multiple sets of stress change amplitude curves.

[0050] Specifically, under normal circumstances, the horizontal principal in-situ stress value of the borehole surrounding rock increases with the increase of drilling depth, but it is currently impossible to observe in real time the actual change of the in-situ stress of the borehole surrounding rock during the drilling process of the drill rod, which may easily cause local in-situ stress concentration inside the borehole, resulting in collapse of the part near the outside of the borehole, thereby causing a safety accident; for this reason, in this embodiment, the in-situ stress value of the borehole surrounding rock at the same test time node in the stress change amplitude curve on the same sub-coordinate system in multiple sub-models can be used to monitor the in-situ stress of the borehole surrounding rock in the same monitoring direction of multiple sections of the short section to be tested, and the in-situ stress of the borehole surrounding rock in the same monitoring direction of multiple sections of the short section to be tested can be monitored according to the in-situ stress value of the borehole surrounding rock at the same test time node in the stress change amplitude curve on the same sub-coordinate system in multiple sub-models, and the in-situ stress of the borehole surrounding rock in the same monitoring direction of multiple sections of the short section to be tested can be monitored according to the in-situ stress of the borehole surrounding rock in the same monitoring direction The ground stress of the surrounding rock of the short section to be tested is used to analyze the ground stress distribution of the surrounding rock of the borehole where the short section to be tested is located at different depths of the borehole; at the same time, the ground stress value of the surrounding rock of the borehole at the same test time node in the stress change amplitude curve of the four sub-coordinate systems in each sub-model is used to monitor the ground stress of the surrounding rock of the corresponding short section to be tested along different monitoring directions, and the ground stress distribution of the surrounding rock of the borehole around the short section to be tested is analyzed according to the ground stress of the surrounding rock of the short section to be tested along different monitoring directions, so as to accurately monitor the source direction of the ground stress of the surrounding rock of the borehole and make accurate judgments on possible accidents caused by the ground stress change of the surrounding rock of the borehole.

[0051] In this embodiment, in order for construction personnel to promptly detect changes in ground stress, an alarm threshold for ground stress of the surrounding rock of the borehole is set, and the control unit controls the stress detection unit to obtain stress detection information on the corresponding short section to be tested in real time. Then, based on the alarm threshold for ground stress of the surrounding rock of the borehole and the current detection value of ground stress in the stress detection information, it is determined whether the ground stress of the surrounding rock of the borehole on the corresponding short section to be tested is close to the bearing range of the short section to be tested, wherein:

[0052] If the in-situ stress alarm threshold of the borehole surrounding rock is greater than or equal to the current detection value of the in-situ stress in the stress detection information, the in-situ stress of the borehole surrounding rock on the short section to be tested is close to the pressure bearing range of the short section to be tested, and the control unit issues an alarm message to promptly remind the construction personnel. After the construction personnel eliminate the alarm message, the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short section to be tested according to the monitoring cycle;

[0053] If the ground stress alarm threshold of the borehole surrounding rock is less than the current detection value of the ground stress in the stress detection information, the ground stress of the borehole surrounding rock on the short joint to be tested is lower than the bearing range of the short joint to be tested, and the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short joint to be tested according to the monitoring period.

[0054] In the above, the control unit uses time as a reference axis and sequentially inputs the time determined by the recorded alarm information into the judgment module to obtain an alarm frequency with time as a reference. The interval value between the alarm frequencies is used to determine whether the interval time between the alarm information tends to diverge or tends to be concentrated;

[0055] If the intervals between alarm messages tend to diverge, it means that the current ground stress of the surrounding rock of the borehole triggers the alarm message due to temporary ground stress concentration caused by the vibration of the drill bit during the drilling process due to the hard stratum geology. The alarm message can be eliminated by the construction personnel to avoid misjudgment and affect normal construction.

[0056] If the interval time between the alarm messages tends to be concentrated, it means that the ground stress of the surrounding rock of the borehole continues to concentrate toward the inside of the borehole. It is necessary to suspend the drilling construction and take corresponding support measures near the borehole. If drilling continues, it is easy to cause local ground stress concentration inside the borehole, resulting in collapse of the area near the outside of the borehole, thereby causing a safety accident.

[0057] The above describes the implementation methods of the present application in detail in conjunction with the accompanying drawings, but the present application is not limited to the above implementation methods. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present application.

Claims

1. A drilling stress monitoring method, characterized in that: include: Step S1: Divide the drill pipe into multiple short sections to be tested, and install a stress detection unit on each of the short sections to be tested; Step S2: connecting the stress detection units on the multiple sections of the short sections to be tested to a control unit respectively, the control unit controlling the stress detection units to collect the ground stress exerted on the surface of the short section to be tested by the surrounding rock of the borehole during the drilling process of the corresponding short section to be tested, obtaining several groups of stress detection information, and uploading the several groups of stress detection information to the control unit; Step S3: The control unit imports several groups of stress detection information into the drilling stress monitoring model, and draws multiple groups of stress change amplitude curves, wherein: The drilling stress monitoring model is provided with a plurality of sub-models, each of which corresponds to each of the stress detection units, and is used to store the stress detection information uploaded by the corresponding stress detection unit, and to draw a stress change amplitude curve according to a plurality of continuous stress detection information within a certain time period; Step S4: monitoring the stress change of the surrounding rock of the borehole during the drilling construction process according to the multiple groups of stress change amplitude curves.

2. The drilling stress monitoring method according to claim 1, characterized in that: In step S1, the stress detection unit includes four groups of stress acquisition modules evenly distributed along the circumference of the short section to be tested, and the four groups of stress acquisition modules are respectively used to collect the ground stress applied by the surrounding rock of the borehole on the surface of the short section to be tested along the four directions of east, west, south and north.

3. The drilling stress monitoring method according to claim 2, characterized in that: In step S2, a monitoring cycle is set, and the control unit controls the four stress acquisition modules on each of the short sections to be tested to respectively collect the ground stresses applied by the surrounding rock of the borehole along the four directions of east, west, south and north on the surface of the short section to be tested according to the monitoring cycle, to obtain four sets of stress detection information, and convert the four sets of stress detection information into digital signals and upload them to the control unit, wherein: The stress acquisition module includes a stress acquisition sensor and a data processor. The stress acquisition sensor is used to collect the ground stress of the borehole surrounding rock, obtain the stress detection information, and send the stress detection information to the data processor to convert it into a digital signal and upload it to the control unit. The data processor is also used to receive the control instructions issued by the control unit, and send the control instructions to the stress acquisition sensor to collect the ground stress of the borehole surrounding rock.

4. The drilling stress monitoring method according to claim 1, characterized in that: In the step S3, a stress monitoring coordinate system is set in the sub-model, and the stress monitoring coordinate system is a plane coordinate axis set in a cross, wherein: The stress monitoring coordinate system uses a number of continuity test time nodes within a monitoring period as abscissas, and the values ​​of the number of continuity test time nodes on the abscissas are symmetrically arranged with the origin of the stress monitoring coordinate system as the center; The stress monitoring coordinate system uses a number of continuous borehole surrounding rock in-situ stress values ​​as ordinates, and the number of continuous borehole surrounding rock in-situ stress values ​​on the ordinates are symmetrically arranged with the origin of the stress monitoring coordinate system as the center; The values ​​of several of the continuity test time nodes and several of the continuity borehole surrounding rock stress values ​​are respectively increased successively from the origin along the axis direction to form four sub-coordinate systems for drawing stress change amplitude curves in four different monitoring directions.

5. The drilling stress monitoring method according to claim 4, characterized in that: In the step S3, the four groups of stress detection information collected on the same short joint to be tested are respectively imported into the corresponding sub-models, and corresponding stress change amplitude curves are respectively drawn on the four sub-coordinate systems of the sub-model.

6. The drilling stress monitoring method according to claim 5, characterized in that: In the step S4, the in-situ stress values ​​of the surrounding rocks of the borehole at the same test time node in the stress variation amplitude curve on the same sub-coordinate system in the multiple sub-models are used to monitor the in-situ stress magnitudes of the surrounding rocks of the boreholes in the same monitoring direction of the multiple sections of the short sections to be tested, and the in-situ stress distribution of the surrounding rocks of the boreholes where the short sections to be tested are located at different depths of the boreholes is analyzed according to the in-situ stress magnitudes of the surrounding rocks of the multiple sections of the short sections to be tested along the same monitoring direction; According to the ground stress values ​​of the borehole surrounding rock at the same test time node in the stress change amplitude curves on the four sub-coordinate systems in each of the sub-models, the ground stress magnitudes of the borehole surrounding rock of the corresponding short section to be tested along different monitoring directions are monitored, and according to the ground stress magnitudes of the borehole surrounding rock of the short section to be tested along different monitoring directions, the ground stress distribution of the borehole surrounding rock around the short section to be tested is analyzed.

7. The drilling stress monitoring method according to claim 1, characterized in that: The in-situ stress alarm threshold of the borehole surrounding rock is set, and the stress detection unit is controlled by the control unit to obtain the stress detection information on the corresponding short section to be tested in real time, and then according to the in-situ stress alarm threshold of the borehole surrounding rock and the current detection value of the in-situ stress in the stress detection information, it is judged whether the in-situ stress of the borehole surrounding rock on the corresponding short section to be tested is close to the pressure range of the short section to be tested, wherein: If the in-situ stress alarm threshold of the borehole surrounding rock is greater than or equal to the current detection value of the in-situ stress in the stress detection information, the in-situ stress of the borehole surrounding rock on the short section to be tested is close to the pressure-bearing range of the short section to be tested, and the control unit sends out an alarm message to promptly remind the construction personnel until the construction personnel eliminate the alarm message, and the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short section to be tested according to the monitoring period; If the ground stress alarm threshold of the borehole surrounding rock is less than the current detection value of the ground stress in the stress detection information, the ground stress of the borehole surrounding rock on the short section to be tested is lower than the bearing range of the short section to be tested, and the control unit controls the stress detection unit to continuously obtain the stress detection information on the corresponding short section to be tested according to the monitoring period.

8. The drilling stress monitoring method according to claim 7, characterized in that: The control unit uses time as a reference axis, and sequentially inputs the time determined by the recorded alarm information into the judgment module to obtain an alarm frequency with time as a reference, and determines whether the interval time between the alarm information tends to diverge or tends to concentrate through the interval value between the alarm frequencies, wherein: If the intervals between alarm messages tend to diverge, it means that the current ground stress of the surrounding rock of the borehole triggers the alarm message because the drill bit vibrates due to the hard stratum during the drilling process. The alarm message can be eliminated by the construction personnel to avoid misjudgment. If the intervals between alarm messages tend to be concentrated, it means that the ground stress of the surrounding rock of the borehole continues to concentrate inside the borehole, and it is necessary to suspend the drilling construction and take corresponding support measures near the borehole.

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