A deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device and method

Abstract

This invention relates to the field of stress monitoring technology, specifically to a multi-point, wall-mounted, three-dimensional mining stress monitoring device and method for deep boreholes. The device includes an outer tube and an inner column, the outer tube having an inner cavity; a side groove is formed along the axial direction of the outer tube's side wall; a stress monitoring element is pre-installed within the side groove; a power source is formed within the inner cavity, enabling the stress monitoring element to adhere tightly to the inner wall of the deep borehole; wherein the outer tube can be spliced ​​according to the depth of the deep borehole. In this invention, for the splicing of multiple outer tube sections, angle sensors are installed at the splicing points to determine the angle between each section of the outer tube and the bottommost section during monitoring. Trigonometric functions are then used to calculate the error value that the stress monitoring element on each section of the outer tube needs to compensate for, thereby improving the accuracy of the three-dimensional mining stress monitoring results through compensation.

Description

Technical Field

[0001] The present invention relates to the technical field of stress monitoring, and in particular to a device and method for monitoring the full-section multi-point wall-attached three-dimensional mining stress. Background Art

[0002] For deep drilling, three-dimensional mining stress monitoring can monitor the stress state of underground rock in real time, promptly discover potential safety hazards, prevent accidents, and ensure the safety of miners and equipment. In addition, through accurate measurement of stress distribution, mining plans can be optimized, resources can be rationally allocated, mining efficiency can be improved, and costs can be reduced.

[0003] Deep drilling technology is to use drilling equipment to drill deep holes underground so that the monitoring device can be installed at a specific depth and position. Strain gauges, fiber optic sensors or other sensor technologies are then used to measure the stress changes inside the rock mass. By analyzing the data from multiple monitoring points, the three-dimensional stress distribution can be reconstructed.

[0004] If you want to achieve full-section multi-point monitoring, you must use rigid parts to install the monitoring device at the specified position. For example, Chinese patent announcement No. CN105784206B discloses a deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device and method. Specifically, first complete the hole making, use a 54mm diameter diamond drill bit to drill the hole, drill to a certain depth in the elastic zone, and clean the hole; according to the drilling depth, select multiple sections of rigid connecting rods of appropriate length, and arrange them in a connection order, wherein a monitoring stress unit is pre-installed on the rigid connecting rod.

[0005] But the problem is:

[0006] In the case of using a single-section rigid connecting rod, the flexibility of the monitoring stress unit is poor.

[0007] In the case of multi-section rigid connecting rods, the rigid connecting rods are prone to tilt at the connection points. If the error caused by the tilt cannot be compensated, the accuracy of the three-dimensional mining stress monitoring results will be reduced. Summary of the invention

[0008] The purpose of the present invention is to provide a deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device and method to solve the problems raised in the above background.

[0009] One of the purposes of the present invention is to provide a deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device, which comprises an outer tube and an inner column, wherein the outer tube has an inner cavity;

[0010] The side wall of the outer tube is provided with a side groove along its axial direction;

[0011] A stress monitoring component is pre-installed in the side groove, and the stress monitoring component in the side groove is arranged corresponding to the monitoring position in the deep borehole;

[0012] The inner column forms a power source in the inner cavity, so that the stress monitoring element can be closely attached to the inner wall of the deep borehole;

[0013] Among them, when the number of sections of the outer tube is greater than or equal to 2, they are spliced ​​in pairs, and an angle sensor is installed at the splicing point to determine the angle between each section of the outer tube and the bottom outer tube during the monitoring process, and then use trigonometric functions to calculate the error value that needs to be compensated for the stress monitoring device on each section of the outer tube.

[0014] As a further improvement of the technical solution, the stress monitoring component includes a shell, and a receiving groove is provided on the front side of the shell;

[0015] The accommodating groove is provided with a strain gauge, a substrate and a flexible layer in sequence from the inside to the outside;

[0016] It also includes a tail plate, which is arranged on the back side of the shell, and the back side is the side facing away from the inner wall of the deep drilling hole;

[0017] The top of the tail plate is provided with an inclined surface;

[0018] The shell can be pre-positioned in the side groove according to the monitoring position of the deep drilling hole.

[0019] As a further improvement of the technical solution, the strain gauge and the substrate are accommodated in the accommodating groove, and the front side of the substrate is exposed to the outside, and the flexible layer is arranged on the front side of the substrate;

[0020] Among them, the front side is the side facing the inner wall of the deep borehole during monitoring.

[0021] As a further improvement of the technical solution, positioning plates are provided on both side walls of the shell in the horizontal direction, a slider is provided on the side of the positioning plate facing the shell, and a sliding groove slidably connected to the slider is provided on the side wall of the shell;

[0022] The two inner walls of the side groove in the horizontal direction are provided with positioning grooves adapted to the width of the positioning plate, and the outer edge of the entry groove communicating with the inner cavity is bonded to the outer edge of the shell near the upper end of the positioning groove.

[0023] As a further improvement of the technical solution, the head of the inner column is chamfered.

[0024] As a further improvement of the technical solution, the inner wall of the outer tube is provided with support plates in an annular array, and the support plates form a space for the inner column to be inserted into the inner cavity;

[0025] The inner column and the support plate form a space whose radius is adapted;

[0026] A wire trough is formed between two adjacent support plates and the outer side wall of the inner column, and the cables used by the stress monitoring device are laid through the wire trough.

[0027] As a further improvement of the present technical solution, 3n side grooves are arranged in an annular array along the axial direction on the side wall of the outer tube, where n is an integer greater than or equal to 1, and each three side grooves form a group. The angle between two adjacent side grooves in the same group is 120°, and at least one group of side grooves at the same height is selected to carry a stress monitoring device.

[0028] As a further improvement of the technical solution, multiple sections of the outer tube are inserted into the deep drill hole, and angle sensors are provided above the outer tube at the bottom.

[0029] The second object of the present invention is to provide a three-dimensional mining stress monitoring method, using the deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device to monitor the mining stress of the deep borehole, and the specific steps are as follows:

[0030] S1, using a diamond drill bit to drill a hole to obtain a drill hole;

[0031] S2. Determine the number of sections of the outer pipe to be used and the order of installation of the outer pipe according to the depth of the borehole, and arrange stress monitoring components at the corresponding monitoring points in the borehole;

[0032] If the number of used sections of the outer tube is greater than or equal to 2, then S3 is performed; otherwise, S3 is skipped and S4 is performed;

[0033] S3, splicing the multiple sections of outer tubes together according to the installation sequence determined in S2, and after splicing, installing an angle sensor at the splicing position;

[0034] S4, inserting the outer tube into the borehole, and then inserting the inner column into the inner cavity, using the axial thrust generated during the insertion of the inner column to force the stress monitoring component to fit the inner wall of the borehole, after the outer tube is straightened, the stress monitoring component is reset to zero, and then the stress is monitored;

[0035] When the number of used sections of the outer tube is greater than or equal to 2, the error value compensation of the stress monitoring component on each section of the outer tube is completed in cooperation with the angle sensor during the monitoring process.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. In the deep borehole full-section multi-point wall-mounted three-dimensional mining stress monitoring device, on the one hand, the setting of the side groove makes the arrangement of the stress monitoring device more flexible, so that a single section of the outer pipe can also complete the stress monitoring of the borehole. On the other hand, for the splicing of multiple sections of the outer pipe, an angle sensor will be installed at the splicing to determine the angle between each section of the outer pipe and the bottom outer pipe during the monitoring process, and then the trigonometric function is used to calculate the error value that needs to be compensated for the stress monitoring device on each section of the outer pipe, so as to improve the accuracy of the three-dimensional mining stress monitoring results through compensation.

[0038] 2. In the deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device, the flexible layer is attached to the inner wall of the borehole, and after attaching, it will undergo a radial displacement to squeeze the flexible layer and fit closely to the inner wall of the borehole. Based on the flexible nature of the flexible layer, it can adapt to the slight unevenness and shape changes on the inner wall surface of the borehole to ensure close contact with the surface. This fit can reduce bubbles and gaps and improve the accuracy of the signal. In addition, the flexible layer can effectively absorb and disperse stress, so that the substrate can feel the stress state of the surrounding environment more evenly, reducing measurement errors caused by local stress concentration.

[0039] 3. In the three-dimensional mining stress monitoring method, the spliced ​​outer tube is inserted into the borehole, and then the inner column is inserted into the inner cavity. The axial thrust generated during the insertion of the inner column is used to force the flexible layer of the stress monitoring component to fit the inner wall of the borehole. After straightening, the stress monitoring component is reset to zero, and then stress is monitored. During the monitoring process, the angle sensor is used to compensate for the error value of the stress monitoring component on each section of the outer tube, and the accuracy of the three-dimensional mining stress monitoring results is improved through compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the outer tube and inner column structure of the present invention.

[0041] Figure 2 For the present invention Figure 1 A magnified view of the structure at A.

[0042] Figure 3 It is a schematic diagram of the structure of the stress monitoring component of the present invention.

[0043] Figure 4 It is a schematic diagram of the outer tube and inner column top structure of the present invention.

[0044] Figure 5 It is a schematic diagram of the connection structure between the shell and the side groove of the present invention.

[0045] Figure 6 It is a cross-sectional view of the outer tube and inner cavity side structure of the present invention.

[0046] Figure 7 For the present invention Figure 6Enlarged view of the structure at B.

[0047] Figure 8 This is a schematic diagram of the distribution of stress monitoring components of the present invention.

[0048] Fig. 9 This is the second schematic diagram of the distribution of the stress monitoring components of the present invention.

[0049] Fig.10 It is a schematic diagram of the error value calculation principle of the present invention.

[0050] The meaning of each number in the figure is:

[0051] 100, outer tube; 110, inner cavity; 111, support plate; 112, wire slot; 120, side slot; 121, entry slot; 122, positioning slot; 200, inner column;

[0052] 300, stress monitoring component; 310, housing; 311, receiving groove; 312, positioning plate; 3121, slider; 313, slide groove; 320, strain gauge; 330, base; 340, flexible layer; 350, tail plate; 351, inclined surface;

[0053] 400, hole outer layer structure; 410, drilling. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] At present, for the three-dimensional mining stress monitoring of deep boreholes, multiple sections of rigid connecting rods of appropriate lengths are usually connected in sequence, so as to form multiple locations for setting monitoring stress units in the deep borehole. For example, Chinese Patent Publication No. CN105784206B discloses a deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device and method. Specifically, the hole is first made, and a diamond drill bit with a diameter of 54 mm is used to open the hole, drill to a certain depth in the elastic zone, and clean the hole; according to the drilling depth, multiple sections of rigid connecting rods of appropriate lengths are selected and arranged in a connection order, wherein the rigid connecting rods are pre-installed with monitoring stress units.

[0056] The more times the connection is made, the more difficult it is for the whole to maintain verticality with the deep borehole after the rigid connecting rod is connected, which leads to an increase in monitoring error. To address this problem, the present invention proposes a deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device, see Figure 1 and Figure 2As shown, it includes an outer tube 100 constituting a rigid part and an inner column 200 constituting a power part. The outer tube 100 is a rigid hollow tube, so it has an inner cavity 110 inside. A side groove 120 is opened on the side wall of the outer tube 100 along its axial direction. The side groove 120 carries a stress monitoring component 300 (i.e., a monitoring stress unit) according to its own monitoring position within the deep borehole monitoring range. The inner column 200 forms a power source in the inner cavity 110, so that the stress monitoring component 300 can be close to the inner wall of the deep borehole.

[0057] First embodiment, see Figure 1 As shown, the above-mentioned deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device is composed of an inner column 200 and an outer tube 100, combined with Figure 2 , 3n side grooves 120 are arranged in a circular array along the axial direction on the side wall of the outer tube 100, n is an integer greater than or equal to 1, every three side grooves 120 form a group, and the angle between two adjacent side grooves 120 in the same group is 120°. At least one group of side grooves 120 is selected at the same height to carry the stress monitoring device 300. It should be noted that the 120° layout can evenly distribute the monitoring points in different directions at the same height position, so as to effectively capture the stress changes around the deep borehole and avoid the deviation caused by monitoring in a single direction. In comparison, the selection of 30° and 60° settings may lead to a higher data correlation between adjacent monitoring points, reducing the independence of the data. Therefore, it is more preferred that the angle between two adjacent side grooves 120 in the same group is 120°.

[0058] It should be noted that the stress analysis is also performed on the stress monitoring components 300 of the same group, thereby ensuring the effectiveness of the 120° setting.

[0059] See also Figure 3 As shown, the stress monitoring component 300 completes the monitoring of three-dimensional mining stress through the strain gauge 320, the base 330 and the flexible layer 340. The stress monitoring component 300 is connected to the side groove 120 through the housing 310. Specifically:

[0060] The front side of the strain gauge 320 is bonded with a substrate 330. The strain gauge 320 and the substrate 330 are packaged by the housing 310. Therefore, the housing 310 has a receiving groove 311 on the front side. The strain gauge 320 and the substrate 330 are received in the receiving groove 311, and the front side of the substrate 330 is exposed to the outside. Then, a flexible layer 340 is bonded to the front side of the substrate 330 (preferably, the flexible layer 340 is a rubber pad). The working principle of the strain gauge 320 and the substrate 330 is that when the deep drilling hole wall is subjected to external stress, the substrate 330 will deform, thereby causing the strain gauge 320 to also deform. The resistance of the strain gauge 320 (such as a metal foil) will change due to the deformation, so that the strain can be calculated by the resistance change.

[0061] The housing 310 has two horizontal side walls provided with positioning plates 312. The positioning plates 312 have a slider 3121 on one side facing the housing 310. The housing 310 has a sliding groove 313 corresponding to the slider 3121 on the side wall thereof. Figure 5 As shown, the two inner walls of the side groove 120 in the horizontal direction are provided with positioning grooves 122 adapted to the width of the positioning plate 312 (the function of the positioning groove 122 is to cooperate with the positioning plate 312 to constrain the shell 310 so that the shell 310 can move in the side groove 120 along the vertical direction), and the positioning groove 122 is provided with an entry groove 121 connected to the inner cavity 110 near the upper end. The positioning plate 312 is driven by the shell 310 to move along the Figure 5 Enter the entry groove 121 in the direction indicated by the middle arrow. After the positioning plate 312 is completely placed in the positioning groove 122, the shell 310 can be moved vertically along the positioning groove 122 to adjust the position of the stress monitoring component 300 in the side groove 120, and then the positioning plate 312 is fixed in the positioning groove 122 by bolts or magnetic attraction.

[0062] Back to Figure 3 As shown, a tail plate 350 is disposed on the back of the housing 310 , and a slope 351 is disposed on the top of the tail plate 350 .

[0063] It should be emphasized that the front side mentioned above is the side facing the inner wall of the deep borehole during monitoring, and the back side is the opposite side.

[0064] When implementing, see Figure 6 As shown, a diamond drill bit is used to drill a hole, drill to a certain depth, and clean the hole to obtain a borehole 410. The outer layer structure 400 (for example, rock, concrete, coal seam or ore, etc.) outside the borehole 410 constitutes the hole wall, and then the stress monitoring component 300 is installed at different height positions (the specific installation position has been determined in advance), and one or more groups of side grooves 120 are selected at the same height to install the stress monitoring component 300, and then the outer tube 100 is inserted into the borehole 410. In order to facilitate the insertion of the outer tube 100 into the borehole 410, the radius of the outer tube 100 is set to be smaller than the radius of the borehole 410. See Figure 1 As shown, the head of the inner column 200 is inserted into the outer tube 100 from the top thereof; during the insertion process, the inner column 200 generates a downward axial thrust, see Figure 3 and Figure 4 As shown, when the thrust acts on the inclined surface 351, the tail plate 350 (indicated by the dotted line) in the initial position is forced to move radially along the arrow a; Figure 3 and Figure 5As shown, the positioning plate 312 is fixed in the positioning groove 122 by bolts or magnetic attraction. Once the axial thrust generated by the inner column 200 acts on the inclined surface 351, the housing 310 will drive the strain gauge 320, the base 330 and the flexible layer 340 to move radially. When the strain gauge 320, the base 330 and the flexible layer 340 move radially outward, on the one hand, the three directions extend simultaneously, and the position of the outer tube 100 in the borehole 410 can be finely adjusted, so that the outer tube 100 can be coaxial with the borehole 410. On the other hand, see Figure 7 As shown, the flexible layer 340 is attached to the inner wall of the bore 410, and after the attachment, it will undergo a radial displacement ( Figure 7 As shown by arrow b in the figure, the flexible layer 340 is squeezed and closely fits with the inner wall of the borehole 410. Based on the flexible nature of the flexible layer 340, it can adapt to the slight unevenness and shape changes on the inner wall surface of the borehole 410 to ensure close contact with the surface. This fit can reduce bubbles and gaps and improve the accuracy of the signal. In addition, the flexible layer 340 can effectively absorb and disperse stress, so that the substrate 330 can feel the stress state of the surrounding environment more evenly, reducing the measurement error caused by local stress concentration.

[0065] In addition, see Figure 3 As shown, the outer edge of the flexible layer 340 is bonded to the outer edge of the housing 310 , so that the flexible layer 340 can also protect the housing 310 , the strain gauge 320 and the substrate 330 through buffering.

[0066] Preferably, see Figure 1 and Figure 3 As shown, the head of the inner column 200 is chamfered so that it can effectively contact the inclined surface 351.

[0067] In addition, see Figure 2 and Figure 4 As shown, the inner wall of the outer tube 100 is provided with support plates 111 in a circular array. The support plates 111 reduce the space for the inner column 200 to be inserted into the inner cavity 110, so the inner column 200 needs to adapt to the radius of the space. When the inner column 200 is inserted into the inner cavity 110, a wire groove 112 is formed between two adjacent support plates 111 and the outer wall of the inner column 200. The cables used by the stress monitoring device 300 on the same axis are all laid through the wire groove 112 corresponding to the axis to avoid affecting the insertion of the inner column 200. It should be noted here that because the stress monitoring device 300 will be laid in advance, the cables should be straightened as much as possible during the laying, and wire clips should be set to limit the cables when necessary. On the one hand, this can avoid cable entanglement, and on the other hand, considering that there will be more cables on the same axis, reasonable layout can make full use of the space in the wire groove 112.

[0068] Preferably, the number of the support plates 111 is 3n, and the support plates 111 and the side grooves 120 are staggered in a top view.

[0069] Second embodiment, in this embodiment, n=3, see Figure 8 As shown, at the same height, taking one stress monitoring component 300 as the reference, from top to bottom, the angle difference between the stress monitoring components 300 of the first group and the second group as the reference is 40°, and the angle difference between the stress monitoring components 300 of the second group and the third group as the reference is also 40°. It can be seen that stress monitoring components 300 of different heights can be arranged in different groups of side grooves 120, thereby realizing three-dimensional mining stress monitoring at different heights and different monitoring angles within the same range (it needs to be explained here that if the stress monitoring components 300 are only at different heights, but are still located in the same group of side grooves 120, then they are deemed to be at the same monitoring angle).

[0070] The third embodiment, in this embodiment, n=3, see Fig. 9 As shown, from top to bottom, the second group of stress monitoring components 300 are disposed in the three groups of side grooves 120, thereby increasing the monitoring range at the same height.

[0071] Fourth embodiment, see Fig.10 As shown, multiple sections of outer pipes 100 are inserted into the deep borehole, so as to realize multi-monitoring range monitoring of the whole section of the deep borehole, and then compensate for the errors of different monitoring ranges. Assume that: the first section of the outer pipe 100 is perpendicular to the bottom surface of the deep borehole, so the three-dimensional mining stress F1 is accurate, but the second section of the outer pipe 100 is tilted by 15° due to the aging of the bolts ( Fig.10 This is just an example. In reality, such a large angle deviation will not occur). This causes the three-dimensional mining stress F2, which should be in the same direction as F1, to shift by 15°, forming a shift angle θ. Then, using trigonometric functions, the three-dimensional mining stress Fx in the same direction as F1 = F2*cos(θ). The result of F2-Fx is the error value η that needs to be compensated.

[0072] Assuming F2 is 100N, according to the above calculation formula: Fx=F2*cos(θ), where:

[0073] F2=100N;

[0074] cos(θ)≈0.9659;

[0075] So Fx=F2*cos(θ)≈96.59N.

[0076] We can then obtain η=F2-Fx≈100-96.59≈3.41N.

[0077] The fifth embodiment discloses a three-dimensional mining stress monitoring method, which uses the deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device in the above embodiment to monitor the mining stress of the deep borehole, and the specific steps are as follows:

[0078] S1, using a diamond drill bit to drill a hole, drilling to a certain depth, and cleaning the hole to obtain a hole 410;

[0079] S2. Determine the number of sections of the outer tube 100 to be used according to the depth of the borehole 410, determine the installation sequence of the outer tube 100, and install the stress monitoring component 300 in one or more groups of side grooves 120 on the outer tube 100. Here, the specific installation position needs to be determined according to the height requirement of the monitoring;

[0080] If the number of used segments is greater than or equal to 2, proceed to S3, otherwise skip S3 and proceed to S4;

[0081] S3, splicing the multiple sections of the outer tube 100 together according to the installation order determined in S2, and after splicing, installing an angle sensor at the splicing position to determine the angle α between each section of the outer tube 100 and the first section of the outer tube 100 (i.e., the bottom outer tube 100) during the monitoring process, so as to obtain θ=180°-α;

[0082] S4, insert the outer tube 100 into the borehole 410, and then insert the inner column 200 into the inner cavity 110, and use the axial thrust generated during the insertion of the inner column 200 to force the flexible layer 340 of the stress monitoring component 300 to fit the inner wall of the borehole 410, and after the outer tube 100 is straightened, the stress monitoring component 300 is reset to zero, and then the stress is monitored;

[0083] If the number of used sections of the outer tube 100 is greater than or equal to 2, the error value compensation of the stress monitoring component 300 on each section of the outer tube 100 needs to be completed in cooperation with the angle sensor during the monitoring process.

[0084] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A three-dimensional mining stress monitoring device for the entire section of a deep borehole with multiple points attached to the wall, characterized in that: It comprises an outer tube (100) and an inner column (200), wherein the outer tube (100) has an inner cavity (110); A side groove (120) is provided on the side wall of the outer tube (100) along its axial direction; A stress monitoring component (300) is pre-arranged in the side groove (120), and the stress monitoring component (300) in the side groove (120) is arranged corresponding to a monitoring point in the deep borehole; The inner column (200) forms a power source in the inner cavity (110), so that the stress monitoring component (300) can be closely attached to the inner wall of the deep borehole; The outer tube (100) has a number of sections greater than or equal to 2, which are spliced ​​in pairs, and an angle sensor is installed at the splicing point to determine the angle between each section of the outer tube (100) and the bottom outer tube (100) during the monitoring process, and then use trigonometric functions to calculate the error value that needs to be compensated for the stress monitoring component (300) on each section of the outer tube (100); The stress monitoring component (300) comprises a housing (310), and a receiving groove (311) is provided on the front side of the housing (310); The accommodating groove (311) is provided with a strain gauge (320), a base (330) and a flexible layer (340) in sequence from the inside to the outside; It also includes a tail plate (350), wherein the tail plate (350) is arranged on the back side of the housing (310), the back side being the side facing away from the inner wall of the deep drill hole; The top of the tail plate (350) is provided with an inclined surface (351); The housing (310) can be pre-positioned in the side groove (120) according to the monitoring position of the deep drilling hole; The strain gauge (320) and the substrate (330) are accommodated in the accommodation groove (311), and the front side of the substrate (330) is exposed to the outside, and the flexible layer (340) is arranged on the front side of the substrate (330); Among them, the front side is the side facing the inner wall of the deep borehole during monitoring; Positioning plates (312) are provided on both side walls of the shell (310) in the horizontal direction, a sliding block (3121) is provided on the side of the positioning plate (312) facing the shell (310), and a sliding groove (313) slidably connected to the sliding block (3121) is provided on the side wall of the shell (310); Positioning grooves (122) adapted to the width of the positioning plate (312) are provided on two inner walls in the horizontal direction of the side groove (120), and an entry groove (121) communicating with the inner cavity (110) is provided near the upper end of the positioning groove (122).

2. The deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device according to claim 1 is characterized in that: The outer edge of the flexible layer (340) is bonded to the outer edge of the shell (310).

3. The deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device according to claim 1 is characterized in that: The head of the inner column (200) is chamfered.

4. The deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device according to claim 1 is characterized in that: The inner wall of the outer tube (100) is provided with support plates (111) in a circular array, and the support plates (111) form a space for the inner column (200) to be inserted into the inner cavity (110); The inner column (200) and the support plate (111) form a space whose radius is adapted; A wire trough (112) is formed between two adjacent support plates (111) and the outer side wall of the inner column (200), and cables used by the stress monitoring component (300) are all laid through the wire trough (112).

5. The deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device according to claim 1 is characterized in that: 3n side grooves (120) are arranged in an annular array along the axial direction on the side wall of the outer tube (100), where n is an integer greater than or equal to 1, and every three side grooves (120) form a group, and the angle between two adjacent side grooves (120) in the same group is 120 degrees. At least one group of side grooves (120) is selected at the same height to carry a stress monitoring component (300).

6. A three-dimensional mining stress monitoring method, characterized in that: The mining stress of a deep borehole is monitored by using the deep borehole full-section multi-point wall-attached three-dimensional mining stress monitoring device as described in any one of claims 1 to 5, and the specific steps are as follows: S1, using a diamond drill bit to drill a hole to obtain a drill hole (410); S2, determining the number of sections of the outer tube (100) to be used and the installation sequence of the outer tube (100) according to the depth of the borehole (410), and arranging stress monitoring components (300) corresponding to monitoring points in the borehole (410); Wherein, the number of use sections of the outer tube (100) is greater than or equal to 2; S3, splicing the multiple sections of outer tube (100) together according to the installation sequence determined in S2, and after splicing, installing an angle sensor at the splicing point; S4, inserting the outer tube (100) into the borehole (410), and then inserting the inner column (200) into the inner cavity (110), using the axial thrust generated during the insertion of the inner column (200) to force the stress monitoring component (300) to fit the inner wall of the borehole (410), and after the outer tube (100) is straightened, the stress monitoring component (300) is reset to zero, and then stress monitoring is performed; During the monitoring process, the angle sensor is used to complete error compensation of the stress monitoring component (300) on each section of the outer tube (100).

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