Coal rock mass three-dimensional stress monitoring sensor and method considering temperature and pore pressure

Abstract

The present invention discloses a coal rock mass three-dimensional stress monitoring sensor and method considering temperature and pore pressure, belonging to the field of stress measurement technology. The three-dimensional stress monitoring sensor includes a shell, a measuring mechanism is arranged in the shell through a synchronous installation mechanism, and the measuring mechanism includes an X-axis stress measurement unit, a Y-axis stress measurement unit and a Z-axis stress measurement unit. The measuring components of the X-axis stress measurement unit, the Y-axis stress measurement unit and the Z-axis stress measurement unit all include a temperature sensor, a pore pressure sensor, a pressure sensor and a stress sensor. At the same time, a method of a coal rock mass three-dimensional stress monitoring sensor based on considering temperature and pore pressure is disclosed, which is provided with a synchronous installation mechanism so that the measuring components located in three directions extend outward synchronously, improve installation efficiency, and are easy to operate. The stress data is corrected according to the temperature data and the pore pressure data to obtain the corrected three-dimensional stress data, thereby improving the monitoring precision and accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of stress measurement, and in particular to a coal rock mass three-dimensional stress monitoring sensor and method taking temperature and pore pressure into consideration. Background Art

[0002] The occurrence of mine dynamic disasters (such as rock burst, rock burst, roof collapse, collapse, water inrush, etc.) is closely related to many factors such as geological environment, surrounding rock structure, lithological characteristics, original rock stress, development layout, mining technology, etc. The source of mine dynamic disasters is the change of original rock stress field (stress redistribution) caused by the interaction of these factors. Therefore, the prerequisite for achieving source control of mine dynamic disasters is to be able to accurately monitor stress changes in coal and rock masses, so as to guide tunnel support, mining area hazard classification and dynamic disaster prediction and prevention.

[0003] At present, the on-site mining stress monitoring in mines is mainly based on the borehole stress monitoring method, which uses sensors installed in the borehole to monitor and obtain the relative stress changes in the coal rock. The stress sensors in the existing technology are complicated to install and do not consider the influence of the temperature and pore pressure of the coal rock mass, resulting in poor stress monitoring accuracy, low disaster source positioning accuracy, and difficulty in effectively identifying key force sources, making it difficult to effectively guide safe mining in mines and monitor, warn and prevent power disasters. Summary of the invention

[0004] The purpose of the present invention is to provide a coal rock mass three-dimensional stress monitoring sensor and method taking into account temperature and pore pressure to solve the above technical problems.

[0005] To achieve the above-mentioned purpose, the present invention provides a coal rock three-dimensional stress monitoring sensor taking temperature and pore pressure into consideration, comprising a shell, a measuring mechanism is arranged in the shell through a synchronous installation mechanism, the measuring mechanism comprises an X-axis stress measurement unit, a Y-axis stress measurement unit and a Z-axis stress measurement unit, the X-axis stress measurement unit, the Y-axis stress measurement unit and the Z-axis stress measurement unit are all installed on the synchronous installation mechanism, the measuring components of the X-axis stress measurement unit, the Y-axis stress measurement unit and the Z-axis stress measurement unit all comprise a temperature sensor, a pore pressure sensor, a pressure sensor and a stress sensor, the synchronous installation mechanism and the measuring components are both electrically connected to a monitor at one end of the shell, and at least two fixing plates are arranged on the circumferential side of one end of the shell.

[0006] Preferably, the synchronous installation mechanism includes a synchronous installation motor installed at one end of the shell, the output shaft of the synchronous installation motor is connected to one end of the driving shaft, the driving shaft is installed inside the shell through a bearing, a first bevel gear is installed at the other end of the driving shaft, the first bevel gear is meshed with the second bevel gear, the second bevel gear is installed at one end of the transmission shaft, the transmission shaft is installed in the shell and a transmission gear is installed at the other end of the transmission shaft, the transmission gear is meshed with a Z-axis driving rack slidably set in the shell, the Z-axis driving rack is connected to the Z-axis stress measurement unit through an L-shaped connecting plate, a driving gear is installed in the middle of the driving shaft, the driving gear is meshed with an X-axis driving rack slidably set in the shell through a reverse gear, the X-axis driving rack is connected to the X-axis stress measurement unit through an L-shaped connecting plate; the driving gear is meshed with a Y-axis driving rack slidably set in the shell, and the Y-axis driving rack is connected to the Y-axis stress measurement unit through a T-shaped connecting plate.

[0007] Preferably, the X-axis stress measurement unit comprises an X-axis arc-shaped mounting plate connected to the X-axis driving rack, and measurement components are linearly distributed on the X-axis arc-shaped mounting plate.

[0008] Preferably, the Y-axis stress measurement unit comprises a Y-axis arc-shaped mounting plate connected to the T-shaped connecting plate, and the Y-axis arc-shaped mounting plate is linearly distributed with measurement components.

[0009] Preferably, the Z-axis stress measuring unit comprises a Z-axis mounting plate mounted on the L-shaped connecting plate, and a plurality of evenly arranged measuring components are arranged on the Z-axis mounting plate.

[0010] Preferably, a Z-axis protection mechanism is arranged at the other end of the shell, and the Z-axis protection mechanism includes two connected fixing rings, and the fixing rings are provided with a plurality of circumferentially distributed guide parts, and the guide parts are provided with guide holes. A plurality of circumferentially distributed Z-axis protection plates are arranged between the two fixing rings, and a movable hinge point is arranged on the Z-axis protection plate, and a fixed hinge point is arranged on one of the fixing rings, and both ends of the protection electric push rod are respectively hinged to the movable hinge point and the fixed hinge point, and the protection electric push rod is electrically connected to the monitor.

[0011] Preferably, a first through hole and a second through hole are formed on the circumferential side of the shell, and the first through hole and the second through hole are respectively arranged opposite to the X-axis arc-shaped mounting plate and the Y-axis arc-shaped mounting plate.

[0012] Preferably, a circumferential side protection mechanism is provided on the inner side of the shell, and the circumferential side protection mechanism includes a protection drive gear ring slidably arranged on the inner side of the shell, and an X-axis protection plate and a Y-axis protection plate are arranged on the protection drive gear ring, and the protection drive gear ring is meshed with the half gear of the drive shaft.

[0013] Preferably, a support mechanism is arranged outside the shell, the support mechanism comprises at least three support units, the support unit comprises an inclined support spring sheet, and a roller is arranged at the free end of the support spring sheet.

[0014] A method for a coal rock mass three-dimensional stress monitoring sensor based on the above-mentioned consideration of temperature and pore pressure, the specific steps are as follows:

[0015] Step S1: drilling a hole at a monitoring location according to a preset depth and angle to obtain a measuring hole;

[0016] Step S2: install the coal rock three-dimensional stress monitoring sensor taking into account temperature and pore pressure into the measuring hole, insert the bottom of the shell into the measuring hole, and under the action of the roller of the supporting mechanism, the bottom of the shell enters the bottom of the measuring hole, and one end of the shell is fixed to the outside of the measuring hole by a fixing plate, and the synchronous installation motor and the protective electric push rod are started to rotate the rotating shaft, and at the same time drive the Z-axis driving rack, the X-axis driving rack and the Y-axis driving rack to move outward, and at the same time, multiple Z-axis protective plates move outward, so that the Z-axis protective mechanism forms an opening for the Z-axis mounting plate with the measuring component installed to pass through, the rotating shaft rotates to drive the half gear to rotate, so that the protective driving gear ring rotates, and the X-axis protective plate and the X-axis protective plate move from the relative position with the first through hole and the second through hole to the relative setting position with the inner wall of the shell, and are used for the X-axis arc mounting plate and the Y-axis arc mounting plate to pass through the first through hole and the second through hole respectively, until the pressure sensor in the measuring unit reaches the set value, and the synchronous installation motor stops;

[0017] Step S3: The monitor collects stress data, temperature data and pore pressure data collected by the measuring component in real time, and corrects the stress data according to the temperature data and pore pressure data to obtain corrected three-dimensional stress data. The correction formula is:

[0018] (1)

[0019] (2)

[0020] (3)

[0021] in, , is a fixed coefficient, , , as well as are respectively a first fixed constant, a second fixed constant, a third fixed constant and a fourth fixed constant; , is the first volume thermal expansion coefficient, , is the second volume thermal expansion coefficient, is the Laplace transform of radial displacement, b is the Biot coefficient, is a field variable, is the latent heat associated with the change in fluid mass, , is the radial distance, and All about , The function of , is the pore pressure change, is the temperature change, is the far-field mean stress, is Poisson's ratio, is the initial pore pressure, is the drilling pressure, is the initial temperature, is the hole wall temperature;

[0022] The calculation formula for three-dimensional stress monitoring is:

[0023] (4)

[0024] (5)

[0025] (6)

[0026] Where: E is the elastic modulus, , , are the strains in the x, y, and z directions, respectively, is the hoop strain, R is the core radius, is the drilling radius, is the conversion factor.

[0027] Therefore, the present invention adopts the above-mentioned coal rock triaxial stress monitoring sensor and method considering temperature and pore pressure, which has the following beneficial effects:

[0028] (1) A synchronous installation mechanism is provided, so that the measuring components located in three directions extend outward synchronously, which improves the installation efficiency and is simple and convenient to operate.

[0029] (2) The measurement components include temperature sensor, pore pressure sensor, pressure sensor and stress sensor. The stress data is corrected according to the temperature data and pore pressure data to obtain the corrected three-dimensional stress data, thereby improving the monitoring precision and accuracy.

[0030] (3) The three-dimensional stress monitoring sensor of the present invention is applicable to both coal and rock masses and can be used for stress monitoring in coal mines, metal mines and other rock mass projects, thereby improving its applicability and having broad application prospects.

[0031] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A three-dimensional diagram of a coal rock mass three-dimensional stress monitoring sensor taking temperature and pore pressure into consideration according to the present invention;

[0033] Figure 2 It is a structural schematic diagram of the synchronous installation mechanism and the measuring mechanism of the present invention;

[0034] Figure 3 It is a schematic diagram of the structure of the Z-axis protection mechanism of the present invention.

[0035] Reference numerals

[0036] 1. Housing; 11. Fixing plate; 12. First through hole; 13. Second through hole; 2. Synchronous mounting mechanism; 21. Synchronous mounting motor; 22. Driving shaft; 23. First bevel gear; 24. Second bevel gear; 25. Transmission shaft; 26. Transmission gear; 27. Z-axis driving rack; 28. L-shaped connecting plate; 29. ​​Driving gear; 210. Reverse gear; 211. X-axis driving rack; 212. Y-axis driving rack; 213. T-shaped connecting plate; 3. X-axis arc mounting Mounting plate; 4. Y-axis arc mounting plate; 5. Z-axis mounting plate; 6. Measuring assembly; 7. Monitor; 8. Z-axis protection mechanism; 81. Fixed ring; 82. Guide part; 83. Guide hole; 84. Z-axis protection plate; 85. Moving hinge point; 86. Fixed hinge point; 87. Protective electric push rod; 9. Circumferential side protection mechanism; 91. Protective drive gear ring; 92. X-axis protection plate; 93. Y-axis protection plate; 94. Half gear; 10. Support spring sheet; 101. Roller. DETAILED DESCRIPTION

[0037] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0039] like Figure 1 As shown, a coal rock three-dimensional stress monitoring sensor considering temperature and pore pressure includes a shell 1, a measuring mechanism is arranged in the shell 1 through a synchronous installation mechanism 2, the measuring mechanism includes an X-axis stress measuring unit, a Y-axis stress measuring unit and a Z-axis stress measuring unit, the X-axis stress measuring unit, the Y-axis stress measuring unit and the Z-axis stress measuring unit are all installed on the synchronous installation mechanism 2, and the measuring components 6 of the X-axis stress measuring unit, the Y-axis stress measuring unit and the Z-axis stress measuring unit all include temperature sensors, pore pressure, pressure sensors and stress sensors. The types and quantities of sensors can also be increased according to actual conditions. The temperature sensor, pore pressure, pressure sensor and stress sensor are all conventional measuring components in the field, and their specific models are no longer limited here. The synchronous installation mechanism 2 and the measuring component 6 are both electrically connected to the monitor 7 at one end of the shell 1, and four fixing plates 11 are arranged on the circumferential side of one end of the shell 1 for fixing the shell 1.

[0040] like Figure 2 As shown, in order to realize the synchronous action of the measuring assembly 6 in three directions, a synchronous installation mechanism 2 is provided, and the synchronous installation mechanism 2 includes a synchronous installation motor 21 installed at one end of the housing 1, and the output shaft of the synchronous installation motor 21 is connected to one end of the driving shaft 22, and the driving shaft 22 is installed inside the housing 1 through a bearing, and a first bevel gear 23 is installed at the other end of the driving shaft 22, and the first bevel gear 23 is meshed with the second bevel gear 24, and the second bevel gear 24 is installed at one end of the transmission shaft 25, and the transmission shaft 25 is installed in the housing 1 and the other end of the transmission shaft 25 is installed with a transmission gear 26, and the transmission gear 26 is meshed with the second bevel gear 24. A Z-axis driving rack 27 slidably disposed in the housing 1 is meshed with each other, and the Z-axis driving rack 27 is connected to a Z-axis stress measuring unit via an L-shaped connecting plate 28. A driving gear 29 is installed in the middle of the driving shaft 22, and the driving gear 29 is meshed with an X-axis driving rack 211 slidably disposed in the housing 1 via a reverse gear 210, and the X-axis driving rack 211 is connected to the X-axis stress measuring unit via an L-shaped connecting plate 28; the driving gear 29 is meshed with a Y-axis driving rack 212 slidably disposed in the housing 1, and the Y-axis driving rack 212 is connected to the Y-axis stress measuring unit via a T-shaped connecting plate 213.

[0041] The X-axis stress measuring unit comprises an X-axis arc-shaped mounting plate 3 connected to the X-axis driving rack 211, and a measuring assembly 6 is linearly distributed on the X-axis arc-shaped mounting plate 3, which is used to measure the stress in the X-axis direction, as well as the temperature and pore pressure of the corresponding measuring point.

[0042] The Y-axis stress measurement unit comprises a Y-axis arc-shaped mounting plate 4 connected to the T-shaped connecting plate 213, and measurement components 6 are linearly distributed on the Y-axis arc-shaped mounting plate 4, which are used to measure the stress in the Y-axis direction, as well as the temperature and pore pressure of the corresponding measurement points.

[0043] The Z-axis stress measuring unit comprises a Z-axis mounting plate 5 mounted on an L-shaped connecting plate 28, on which a plurality of evenly arranged measuring components 6 are arranged, for measuring stress in the Z-axis direction, and the temperature and pore pressure at the corresponding measuring points.

[0044] The other end of the housing 1 is provided with a Z-axis protection mechanism 8, such as Figure 3 As shown, the Z-axis protection mechanism 8 includes two connected fixed rings 81, the fixed rings 81 are provided with a plurality of circumferentially distributed guide portions 82, the guide portions 82 are provided with guide holes 83, a plurality of circumferentially distributed Z-axis protection plates 84 are provided between the two fixed rings 81, a movable hinge point 85 is provided on the Z-axis protection plate 84, one of the fixed rings 81 is provided with a fixed hinge point 86, two ends of a protection electric push rod 87 are respectively hinged to the movable hinge point 85 and the fixed hinge point 86, the protection electric push rod 87 is electrically connected to the monitor 7 to realize the opening and closing of the other end of the shell 1, and when the shell 1 is installed, the Z-axis stress measurement unit is protected.

[0045] The circumferential side of the shell 1 is provided with a first through hole 12 and a second through hole 13, which are respectively arranged opposite to the X-axis arc mounting plate 3 and the Y-axis arc mounting plate 4, so that the X-axis arc mounting plate 3 and the Y-axis arc mounting plate 4 can carry the measuring assembly 6 through the through holes and fit with the measuring hole wall. A circumferential side protection mechanism 9 is arranged on the inner side of the shell 1, and the circumferential side protection mechanism 9 includes a protection drive gear ring 91 slidably arranged on the inner side of the shell 1, and an X-axis protection plate 92 and a Y-axis protection plate 93 are arranged on the protection drive gear ring 91, and the protection drive gear ring 91 is meshed with a half gear 94 of the drive shaft 22. When the shell 1 is installed, the X-axis stress measurement unit and the Y-axis stress measurement unit are protected.

[0046] A support mechanism is arranged outside the shell 1, and the support mechanism includes at least three support units. The support unit includes an inclined support spring sheet 10, and a roller 101 is arranged at the free end of the support spring sheet 10, so that the shell 1 can enter the measuring hole more smoothly and be in the middle position.

[0047] A method for a coal rock mass three-dimensional stress monitoring sensor based on the above-mentioned temperature and pore pressure considerations, the specific steps are as follows:

[0048] Step S1: drilling a hole at a monitoring location according to a preset depth and angle to obtain a measuring hole.

[0049] Step S2: Install the coal rock triaxial stress monitoring sensor considering temperature and pore pressure into the measuring hole, insert the bottom of the shell 1 into the measuring hole, and under the action of the roller 101 of the supporting mechanism, the bottom of the shell 1 enters the bottom of the measuring hole, and fixes one end of the shell 1 outside the measuring hole through the fixing plate 11, and starts the synchronous installation motor 21 and the protective electric push rod 87 to rotate the rotating shaft, and at the same time drive the Z-axis driving rack 27, the X-axis driving rack 211 and the Y-axis driving rack 212 to move outward, and at the same time, multiple Z-axis protective plates 84 move outward. The Z-axis protection mechanism 8 forms an opening for the Z-axis mounting plate 5 on which the measuring assembly 6 is installed to pass through, and the rotating shaft rotates to drive the half gear 94 to rotate, so that the protection driving gear ring 91 rotates, and the X-axis protection plate 92 and the X-axis protection plate 92 move from the relative position with respect to the first through hole 12 and the second through hole 13 to the relative position with respect to the inner wall of the shell 1, so that the X-axis arc mounting plate 3 and the Y-axis arc mounting plate 4 pass through the first through hole 12 and the second through hole 13 respectively, until the pressure sensor in the measuring unit reaches the set value, and the synchronous installation motor 21 stops.

[0050] Step S3: The monitor 7 collects the stress data, temperature data and pore pressure data collected by the measuring component 6 in real time, and corrects the stress data according to the temperature data and pore pressure data to obtain the corrected three-dimensional stress data. The correction formula is:

[0051] (1)

[0052] (2)

[0053] (3)

[0054] in, , is a fixed coefficient, , , as well as are respectively a first fixed constant, a second fixed constant, a third fixed constant and a fourth fixed constant; , is the first volume thermal expansion coefficient, , is the second volume thermal expansion coefficient, is the Laplace transform of radial displacement, b is the Biot coefficient, is a field variable, is the latent heat associated with the change in fluid mass, , is the radial distance, and All about , The function of , is the pore pressure change, is the temperature change, is the far-field mean stress, is Poisson's ratio, is the initial pore pressure, is the drilling pressure, is the initial temperature, is the hole wall temperature;

[0055] The calculation formula for three-dimensional stress monitoring is:

[0056] (4)

[0057] (5)

[0058] (6)

[0059] Where: E is the elastic modulus, , , are the strains in the x, y, and z directions, respectively, is the hoop strain, R is the core radius, is the drilling radius, is the conversion factor.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure, comprising a housing, characterized in that: A measuring mechanism is arranged in the shell through a synchronous mounting mechanism, and the measuring mechanism includes an X-axis stress measuring unit, a Y-axis stress measuring unit and a Z-axis stress measuring unit, and the X-axis stress measuring unit, the Y-axis stress measuring unit and the Z-axis stress measuring unit are all mounted on the synchronous mounting mechanism, and the measuring components of the X-axis stress measuring unit, the Y-axis stress measuring unit and the Z-axis stress measuring unit all include a temperature sensor, a pore pressure sensor, a pressure sensor and a stress sensor, and the synchronous mounting mechanism and the measuring components are electrically connected to a monitor at one end of the shell, and at least two fixing plates are arranged on the circumferential side of one end of the shell; The synchronous installation mechanism includes a synchronous installation motor installed at one end of a shell, the output shaft of the synchronous installation motor is connected to one end of a driving shaft, the driving shaft is installed inside the shell through a bearing, a first bevel gear is installed at the other end of the driving shaft, the first bevel gear is meshed with a second bevel gear, the second bevel gear is installed at one end of a transmission shaft, the transmission shaft is installed in the shell and a transmission gear is installed at the other end of the transmission shaft, the transmission gear is meshed with a Z-axis driving rack slidably arranged in the shell, the Z-axis driving rack is connected to a Z-axis stress measuring unit through an L-shaped connecting plate, a driving gear is installed in the middle of the driving shaft, the driving gear is meshed with an X-axis driving rack slidably arranged in the shell through a reverse gear, the X-axis driving rack is connected to the X-axis stress measuring unit through an L-shaped connecting plate; the driving gear is meshed with a Y-axis driving rack slidably arranged in the shell, and the Y-axis driving rack is connected to the Y-axis stress measuring unit through a T-shaped connecting plate.

2. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 1 is characterized by: The X-axis stress measuring unit comprises an X-axis arc-shaped mounting plate connected to an X-axis driving rack, and measuring components are linearly distributed on the X-axis arc-shaped mounting plate.

3. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 2 is characterized by: The Y-axis stress measuring unit comprises a Y-axis arc-shaped mounting plate connected to a T-shaped connecting plate, and measuring components are linearly distributed on the Y-axis arc-shaped mounting plate.

4. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 3 is characterized by: The Z-axis stress measuring unit comprises a Z-axis mounting plate mounted on an L-shaped connecting plate, and a plurality of evenly arranged measuring components are arranged on the Z-axis mounting plate.

5. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 4 is characterized in that: A Z-axis protection mechanism is arranged at the other end of the shell, and the Z-axis protection mechanism includes two connected fixing rings, the fixing rings are provided with a plurality of circumferentially distributed guide parts, the guide parts are provided with guide holes, a plurality of circumferentially distributed Z-axis protection plates are arranged between the two fixing rings, a movable hinge point is arranged on the Z-axis protection plate, a fixed hinge point is arranged on one of the fixing rings, two ends of the protection electric push rod are respectively hinged to the movable hinge point and the fixed hinge point, and the protection electric push rod is electrically connected to the monitor.

6. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 5 is characterized by: A first through hole and a second through hole are opened on the circumferential side of the shell, and the first through hole and the second through hole are respectively arranged opposite to the X-axis arc-shaped mounting plate and the Y-axis arc-shaped mounting plate.

7. The coal rock mass three-dimensional stress monitoring sensor considering temperature and pore pressure according to claim 6 is characterized by: A circumferential side protection mechanism is arranged on the inner side of the shell, and the circumferential side protection mechanism includes a protection drive gear ring slidably arranged on the inner side of the shell, an X-axis protection plate and a Y-axis protection plate are arranged on the protection drive gear ring, and the protection drive gear ring is meshed with the half gear of the drive shaft.

8. The coal-rock triaxial stress monitoring sensor considering temperature and pore pressure according to claim 7 is characterized by: A supporting mechanism is arranged outside the shell, and the supporting mechanism comprises at least three supporting units. The supporting unit comprises a supporting spring sheet arranged obliquely, and a roller is arranged at the free end of the supporting spring sheet.

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