Fiber grating array-based surrounding rock displacement monitoring device and method

Abstract

The application discloses a kind of surrounding rock displacement monitoring device and method based on fiber grating array, including micro fine diameter oil cylinder, micro coarse diameter oil cylinder, temperature self-compensation sensing element, fiber grating array, steel wire rope buckle, plastic sleeve, installation box, bearing, bearing seat, steel wire rope.The application is converted into fiber strain by the structure-fluid transmission of spring, oil cylinder, and the intelligent perception of the state of multiple points in surrounding rock is realized by temperature compensation of symmetrical structure.The application is suitable for surrounding rock displacement monitoring, and can also be used for roadway surrounding rock stability analysis, with simple structure and easy installation, to help the safe and efficient production of coal mine.

Description

Technical Field

[0001] This invention relates to a device and method for monitoring the displacement of surrounding rock based on a fiber optic grating array, belonging to the technical field of displacement monitoring and stability analysis inside the surrounding rock of roadways. Background Technology

[0002] During coal mine production operations, the redistribution of stress in the surrounding rock caused by mining and tunneling disturbances can easily alter the stability of the surrounding rock, leading to instability and seriously threatening the safety of personnel and equipment. Therefore, real-time monitoring and early warning of the deformation state of the surrounding rock in roadways using advanced sensing technology is an important technical means to ensure the safe and efficient production of modern intelligent coal mines.

[0003] Currently, numerous experts, scholars, and engineers have conducted research on the monitoring of deformation in roadway surrounding rock. Among these, optical frequency domain sensing methods, represented by fiber optic sensing, have received widespread attention due to their advantages such as resistance to electromagnetic interference, high sensitivity, and ease of fabrication. However, due to the significant deformation of roadway surrounding rock caused by the combined effects of multiple factors during mining, and the relatively low tensile strength of optical fibers, they are prone to breakage when used for large displacement monitoring. Therefore, there is an urgent need to develop sensing devices capable of monitoring large deformations. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a surrounding rock displacement monitoring device and method based on fiber optic grating array. The deformation of the surrounding rock is transmitted to a miniature small-diameter hydraulic cylinder through a steel wire rope. The piston movement drives the hydraulic oil to be transmitted to a miniature large-diameter hydraulic cylinder through a connecting pipe. Finally, the deformation is transmitted to a temperature self-compensating sensitive element and an equal-strength cantilever beam, thereby realizing the transformation of the large displacement of the surrounding rock in the roadway into the small displacement of the equal-strength cantilever beam.

[0005] Prior to this invention, a rock displacement monitoring device based on a fiber optic grating array is provided, comprising a miniature fine-diameter cylinder sleeve, an upper mounting box, a miniature fine-diameter cylinder, a steel wire rope, a V-bearing, an iron claw, and an earring. The miniature fine-diameter cylinder is installed inside the miniature fine-diameter cylinder sleeve, and an earring is installed at the end of the miniature fine-diameter cylinder. One end of the steel wire rope is fastened to the middle hole of the earring, and the middle part of the steel wire rope passes through the sleeve of the upper mounting box after being reversed by the V-bearing. The other end of the steel wire rope is connected to an iron claw.

[0006] Preferably, the system includes a miniature coarse-diameter hydraulic cylinder, wherein the oil outlet of the miniature fine-diameter hydraulic cylinder is connected to the oil inlet of the miniature coarse-diameter hydraulic cylinder.

[0007] Preferably, the device includes a lower layer of the mounting box, a miniature coarse-diameter cylinder box, and a spring. The miniature coarse-diameter cylinders are arranged in a straight array in the miniature coarse-diameter cylinder box. The bottom end of the miniature coarse-diameter cylinder box is fixed to the top of the lower layer of the mounting box by rectangular buckles, bolts, and nuts. A spring is placed on the top of the miniature coarse-diameter cylinders.

[0008] Preferably, the device includes a lower mounting box, a miniature large-diameter cylinder box, and a spring. The miniature large-diameter cylinder is placed in the miniature large-diameter cylinder box, the bottom of the miniature large-diameter cylinder box is fixed to the top of the lower mounting box, and a spring is placed on the top of the miniature large-diameter cylinder.

[0009] Preferably, the device includes a temperature self-compensating sensitive element array, wherein the top of the spring is in close contact with a through hole on the lower surface of the temperature self-compensating sensitive element array, and the temperature self-compensating sensitive element array is fixed above the miniature large-diameter cylinder box by bolts and nuts.

[0010] Preferably, the device includes a fiber grating array, an equal-strength cantilever beam, and elongated grooves on both the upper and lower surfaces of the temperature self-compensating sensing element array. The equal-strength cantilever beam is disposed within these grooves, and the fiber grating array is welded to it. The width of the equal-strength cantilever beam increases as the distance between its central axis and the root of the beam decreases. The width of the equal-strength cantilever beam's cross-section is a function of the width at its root.

[0011]

[0012] In the formula, F max x represents the maximum normal force acting on the free end of a cantilever beam of equal strength. bm The x-coordinate of the cross section of the cantilever beam of equal strength along its length is represented by l. bm σ represents the distance between the root of a cantilever beam of equal strength and the point of application of the normal force. bm h represents the maximum bending stress at each section of a cantilever beam of equal strength. bm This indicates the thickness of a cantilever beam with equal strength.

[0013] Preferably, a dust cover for the sensitive element is included, which is fixed above the temperature self-compensating sensitive element array.

[0014] Preferably, the mounting box includes an upper layer, a lower layer, a middle layer, a U-shaped clamp, a bearing, and a bearing seat. The bottom end of the bearing seat is fixed to the top end of the lower layer of the mounting box. The bearing seat is fixedly connected to the bearing via a connecting shaft. The lower layer of the mounting box is fixedly connected to the middle layer of the mounting box via the U-shaped clamp. The middle layer of the mounting box is fixedly connected to the upper layer of the mounting box via bolts and nuts.

[0015] A method for monitoring surrounding rock displacement based on fiber optic grating array, utilizing any one of the fiber optic grating array-based surrounding rock displacement monitoring devices described above, performs the following steps:

[0016] Drilling is carried out at the surrounding rock displacement monitoring location using an anchor drilling rig. After drilling is completed, multiple iron claws connected to the wire rope are inserted into the drill hole in sequence through the drill rod, and the upper sleeve of the installation box is inserted into the drill hole.

[0017] Inject oil into the oil inlet to tighten the wire rope;

[0018] The wavelength of the reflected wave from the fiber Bragg grating array is acquired using a demodulator, and the displacement value is calculated by subtracting the wavelengths of the reflected waves. In the formula, i represents the measurement point number. The maximum wavelength. K is the minimum wavelength. (i) The transfer coefficients for the displacement and wavelength conversion model;

[0019] The coal seam and rock strata include compressive strength σ j Cohesion c j , internal friction angle ψ j And the parameters of the roadway burial depth h are used as variables, and the mining distance s is used as a variable. i As input, a deep learning regression model was established to test the deformation of the surrounding rock in the roadway as a function of the mining distance.

[0020] Substitute the actual mining distance and the measured displacement value into the function. The predicted displacement values ​​of the surrounding rock in the roadway are calculated, where o i This represents the output displacement value of the surrounding rock in the tunnel, ω. ij x represents the weighting coefficient. j The compressive strength σ represents the strength of coal seams and rock strata. j Cohesion c j , internal friction angle ψ j and the tunnel depth h, θ i The threshold parameter is used to identify unknown parameters using a swarm intelligence optimization algorithm.

[0021] Substituting the unknown parameters into a deep learning regression model, the model is used to predict the displacement of the surrounding rock in the roadway at different mining distances; if the predicted displacement value of the surrounding rock in the roadway is o i Exceeding the threshold An alarm will be triggered.

[0022] The beneficial effects achieved by this invention are as follows:

[0023] The deformation of the surrounding rock is transmitted to a miniature small-diameter hydraulic cylinder via a steel wire rope. The piston movement drives the hydraulic oil through a connecting pipe to a miniature large-diameter hydraulic cylinder, which in turn transmits the deformation to a temperature self-compensating sensitive element and an equal-strength cantilever beam. This process transforms the large displacement of the surrounding rock in the tunnel into the small displacement of the equal-strength cantilever beam.

[0024] The displacement of multiple measuring points is transmitted from a miniature small-diameter hydraulic cylinder to a miniature large-diameter hydraulic cylinder through a connecting pipe, and finally to multiple temperature self-compensating sensitive elements and an equal-strength cantilever beam structure located on the same straight line. All displacements can then be measured through two symmetrically placed optical fibers, greatly reducing the complexity of data acquisition. Attached Figure Description

[0025] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is an exploded view of the entire invention.

[0027] Figure 2 For the present invention Figure 1 Enlarged view of point A in the middle.

[0028] Figure 3 For the present invention Figure 1 Enlarged view of point B in the middle.

[0029] Figure 4 For the present invention Figure 1 A magnified view of point C in the middle.

[0030] Figure 5 For the present invention Figure 4 Enlarged view of point D in the middle.

[0031] Figure 6 For the present invention Figure 4 Enlarged view of point E in the middle.

[0032] Figure 7 This is a structural diagram of the upper layer of the mounting box in this invention.

[0033] Figure 8 This is a structural diagram of the lower layer of the mounting box in this invention.

[0034] Figure 9 This is a structural diagram of the middle layer of the mounting box in this invention.

[0035] Figure 10 This is a structural diagram of the dust cover for the sensitive element in this invention.

[0036] Figure 11 This is a structural diagram of the miniature large-diameter hydraulic cylinder box in this invention.

[0037] Figure 12 This is a structural diagram of the medium-strength cantilever beam of the present invention.

[0038] The following are the meanings of the reference numerals in the attached diagram: 1-Miniature small-diameter hydraulic cylinder sleeve, 2-Connecting pipe, 3-Upper layer of mounting box, 4-Lower layer of mounting box, 5-Middle layer of mounting box, 6-Fiber optic grating array, 7-Dust cover for sensitive element, 8-Miniature large-diameter hydraulic cylinder box, 9-U-shaped clamp, 10-Miniature small-diameter hydraulic cylinder, 11-Wire rope buckle lock, 12-Wire rope, 13-Bearing, 14-Bearing seat, 15-Spring, 16-Miniature large-diameter hydraulic cylinder, 17-Iron claw, 18-Rectangular buckle, 19-Earring, 20-Temperature self-compensating sensitive element array, 21-Long strip groove, 22-Equal strength cantilever beam, 23-Oil inlet. Detailed Implementation

[0039] In this invention, the terms "first" and "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" and "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention. See also Figure 1 and Figure 2 This application provides a surrounding rock displacement monitoring device based on a fiber optic grating array, including a miniature fine-diameter cylinder sleeve 1, an upper layer of a mounting box 3, a miniature fine-diameter cylinder 10, a steel wire rope 12, a V-bearing 13, an iron claw 17, and an ear ring 19. The miniature fine-diameter cylinder 10 is installed inside the miniature fine-diameter cylinder sleeve 1. The end of the miniature fine-diameter cylinder 10 is threaded with an ear ring 19. One end of the steel wire rope 12 is fastened to the middle hole of the ear ring 19 through a screw and a washer in a steel wire rope buckle lock 11. The middle part of the steel wire rope 12 passes through the sleeve of the upper layer of the mounting box 3 after being reversed by the V-bearing 13. The other end of the steel wire rope 12 is connected to an iron claw 17.

[0040] In this embodiment of the application, a connecting pipe 2 and a miniature coarse-diameter hydraulic cylinder 16 are included. The oil outlet of the miniature fine-diameter hydraulic cylinder 10 is connected to the oil inlet of the miniature coarse-diameter hydraulic cylinder 16 through the connecting pipe 2.

[0041] In the embodiments of this application, such as Figure 4 As shown, the system includes a lower mounting box 4, a miniature large-diameter cylinder box 8, and springs 15. The miniature large-diameter cylinders 16 are arranged in a straight array within the miniature large-diameter cylinder box 8. The bottom of the miniature large-diameter cylinder box 8 is fixed to the top of the lower mounting box 4 by rectangular clips 18, bolts, and nuts. Figure 5 As shown, a spring 15 is placed at the top of the miniature coarse-diameter hydraulic cylinder 16.

[0042] In the embodiments of this application, such as Figure 6As shown, it includes a temperature self-compensating sensitive element array 20. The top of the spring 15 is in close contact with a through hole opened on the lower surface of the temperature self-compensating sensitive element array 20. The temperature self-compensating sensitive element array 20 is fixed above the miniature coarse-diameter hydraulic cylinder box 8 by bolts and nuts.

[0043] In this embodiment, the system includes a fiber grating array 6, an equal-strength cantilever beam 22, and elongated grooves 21 formed on both the upper and lower surfaces of a temperature self-compensating sensing element array 20. The equal-strength cantilever beam 22 is disposed within the elongated grooves 21. The fiber grating array 6 is welded to the equal-strength cantilever beam 22. The width of the equal-strength cantilever beam 22 increases as the distance between the central axis of the equal-strength cantilever beam 22 and its root decreases. The width of the cross-section of the equal-strength cantilever beam 22 and its root are functions of:

[0044]

[0045] In the formula, F max x represents the maximum normal force acting on the free end of the cantilever beam 22 of equal strength. bm The x-coordinate of the section of the equal-strength cantilever beam 22 along its length is represented by l. bm σ represents the distance between the root of the cantilever beam 22 of equal strength and the point of application of the normal force. bm h represents the maximum bending stress at each section of the equal-strength cantilever beam 22. bm The thickness of the cantilever beam 22 of equal strength is indicated. In this embodiment, a dust cover 7 for the sensitive element is included, which is fixed above the temperature self-compensating sensitive element array 20 by bolts and nuts.

[0046] In the embodiments of this application, such as Figure 3 As shown, the device includes a bearing 13 and a bearing housing 14. The bottom end of the bearing housing 14 is fixed to the top end of the lower layer 4 of the mounting box by a rectangular buckle 18, bolts and nuts. The bearing housing 14 is fixedly connected to the bearing 13 by a connecting shaft. The lower layer 4 of the mounting box is fixedly connected to the middle layer 5 of the mounting box by a U-shaped clip 9. The middle layer 5 of the mounting box is fixedly connected to the upper layer 3 of the mounting box by bolts and nuts.

[0047] A method for monitoring surrounding rock displacement based on fiber Bragg grating array, comprising:

[0048] S1: Drill holes at the surrounding rock displacement monitoring location using an anchor drilling rig. After drilling is completed, insert multiple iron claws 17 connected to the wire rope into the drill hole in sequence through the drill rod, and insert the sleeve of the upper layer 3 of the installation box into the drill hole.

[0049] S2: Inject oil into the oil inlet 23 to tighten the wire rope 12;

[0050] S3: Use a demodulator to acquire the reflected wavelengths of the two fiber Bragg grating arrays 6, and use a host computer to perform subtraction on the reflected wavelengths to calculate the displacement value. In the formula, i represents the measurement point number. The maximum wavelength. K is the minimum wavelength. (i) represents the transfer coefficients of the displacement and wavelength conversion model.

[0051] S4: The compressive strength σ of coal seams and rock strata. j Cohesion c j , internal friction angle ψ j And the parameters of the roadway burial depth h are used as variables, and the mining distance s is used as a variable. i As input, a deep learning regression model was established to test the deformation of the surrounding rock in the roadway as a function of the mining distance.

[0052] Substitute the actual mining distance and the measured displacement value into the function. The predicted displacement values ​​of the surrounding rock in the roadway are calculated, where o i This represents the output displacement value of the surrounding rock in the tunnel, ω. ij x represents the weighting coefficient. j The compressive strength σ represents the strength of coal seams and rock strata. j Cohesion c j , internal friction angle ψ j and the tunnel depth h, θ i The threshold parameter is used to identify unknown parameters using a swarm intelligence optimization algorithm.

[0053] Substituting the unknown parameters into a deep learning regression model, the model is used to predict the displacement of the surrounding rock in the roadway at different mining distances; if the predicted displacement value of the surrounding rock in the roadway is o i Exceeding the threshold An alarm will be issued and suggestions to strengthen support measures will be made.

[0054] The connecting tube 2, fiber optic grating array 6, U-shaped clamp 9, miniature fine-diameter hydraulic cylinder 10, wire rope buckle lock 11, wire rope 12, bearing 13, bearing seat 14, spring 15, miniature large-diameter hydraulic cylinder 16, iron claw 17, rectangular buckle 18, earring 19, temperature self-compensating sensitive element array 20, long strip groove 21, equal strength cantilever beam 22, and oil inlet 23 are all available in the prior art. Those skilled in the art can select according to actual needs. No examples will be given in this embodiment.

[0055] like Figure 7-12As shown, the miniature small-diameter cylinder sleeve 1 is a cylindrical rod, the upper layer 3 of the mounting box is a cylindrical rod, and several rectangular plates with through holes are fixedly installed on the upper layer 3 of the mounting box. The lower layer 4 of the mounting box is a flat-bottomed cylindrical shape with a hollow interior and cylindrical hollow connecting pipes evenly arranged around the cylinder. Six U-shaped rods are fixedly installed at the bottom of the lower layer 4 of the mounting box. The middle layer 5 of the mounting box has the same structure as the lower layer 4 of the mounting box. The dust cover 7 of the sensitive element is a cuboid shape with hollow interior and lower surface and rectangular screw holes symmetrically distributed along the long side of the cuboid. The miniature large-diameter cylinder box 8 is a cuboid shape with a hollow interior and evenly distributed partitions and rectangular screw holes symmetrically distributed along the long side of the cuboid. The equal-strength cantilever beam 22 is an inverted trapezoid shape with a rectangular groove along the center line of the trapezoid.

[0056] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0057] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention described herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not invented herein. The specification and embodiments are to be considered exemplary only.

[0058] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", "joining", and "fitting" should be interpreted broadly, and can refer to mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0059] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. The above specific embodiments have further described the purpose, technical solution and beneficial effects of this application in detail. It should be understood that the above are only specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solution of this application should be included within the scope of protection of this application.

Claims

1. A surrounding rock displacement monitoring device based on a fiber optic grating array, characterized in that, Includes a miniature fine-diameter cylinder sleeve (1), an upper layer of the mounting box (3), a miniature fine-diameter cylinder (10), a wire rope (12), a V-bearing (13), an iron claw (17), and an earring (19); the miniature fine-diameter cylinder sleeve (1) is equipped with a miniature fine-diameter cylinder (10), and an earring (19) is installed at the end of the miniature fine-diameter cylinder (10). One end of the wire rope (12) is fastened to the middle hole of the earring (19), and the middle part of the wire rope (12) passes through the sleeve of the upper layer of the mounting box (3) after being reversed by the V-bearing (13). The other end of the wire rope (12) is connected to an iron claw (17). Includes a miniature coarse-diameter hydraulic cylinder (16), wherein the oil outlet of the miniature fine-diameter hydraulic cylinder (10) is connected to the oil inlet of the miniature coarse-diameter hydraulic cylinder (16) via a connecting pipe (2); Includes a lower layer of mounting box (4), a miniature coarse-diameter cylinder box (8), and a spring (15); the miniature coarse-diameter cylinder (16) is placed in the miniature coarse-diameter cylinder box (8), the bottom end of the miniature coarse-diameter cylinder box (8) is fixed to the top end of the lower layer of mounting box (4), and the spring (15) is placed on the top end of the miniature coarse-diameter cylinder (16). Includes a temperature self-compensating sensitive element array (20), the top of the spring (15) is in close contact with the through hole opened on the lower surface of the temperature self-compensating sensitive element array (20), and the temperature self-compensating sensitive element array (20) is fixed above the miniature coarse diameter cylinder box (8) by bolts and nuts; The system includes a fiber grating array (6), an equal-strength cantilever beam (22), and elongated grooves (21) on both the upper and lower surfaces of the temperature self-compensating sensing element array (20). The equal-strength cantilever beam (22) is disposed in the elongated grooves (21). The fiber grating array (6) is welded to the equal-strength cantilever beam (22). The width of the equal-strength cantilever beam (22) increases as the distance between the central axis of the equal-strength cantilever beam (22) and the root of the equal-strength cantilever beam (22) decreases. The function of the width of the cross section of the equal-strength cantilever beam (22) and the root of the equal-strength cantilever beam (22) is: ， In the formula, This represents the maximum normal force acting on the free end of the cantilever beam (22) of equal strength. The x-coordinate of the section of the equal-strength cantilever beam (22) along the length of the equal-strength cantilever beam (22) is represented. This represents the distance between the root of the cantilever beam (22) of equal strength and the point of application of the normal force. This represents the maximum bending stress at each section of the equal-strength cantilever beam (22). The thickness of the equal-strength cantilever beam (22) is indicated.

2. The fiber grating array based surrounding rock displacement monitoring device according to claim 1, characterized in that, The miniature coarse-diameter cylinders (16) are arranged in a straight line in the miniature coarse-diameter cylinder box (8). The bottom of the miniature coarse-diameter cylinder box (8) is fixed to the top of the lower layer (4) of the mounting box by rectangular buckles (18), bolts and nuts.

3. The fiber grating array based surrounding rock displacement monitoring device according to claim 2, characterized in that, It also includes a sensitive element dust cover (7), which is fixed above the temperature self-compensating sensitive element array (20).

4. The fiber grating array based surrounding rock displacement monitoring device according to claim 3, characterized in that, It also includes a middle layer (5) of the mounting box, a U-shaped clamp (9), a bearing (13) and a bearing seat (14). The bottom end of the bearing seat (14) is fixed to the top end of the lower layer (4) of the mounting box. The bearing seat (14) is fixedly connected to the bearing (13) through a connecting shaft. The lower layer (4) of the mounting box is fixedly connected to the middle layer (5) of the mounting box through the U-shaped clamp (9). The middle layer (5) of the mounting box is fixedly connected to the upper layer (3) of the mounting box through bolts and nuts.

5. A method for monitoring displacement of surrounding rock based on fiber grating array, characterized in that, Using the surrounding rock displacement monitoring device based on fiber optic grating array as described in claim 4, the following steps are performed: Drilling is performed at the location of the surrounding rock displacement monitoring by the anchor drilling machine. After the drilling is completed, multiple iron claws (17) that connect the steel wire rope are inserted into the drilling hole in sequence through the drill rod, and the sleeve of the upper layer (3) of the installation box is inserted into the drilling hole. Inject oil into the oil inlet (23) to tighten the wire rope (12); The wavelength of the reflected wave from the fiber grating array (6) was acquired using a demodulator, and the displacement value was calculated by subtracting the wavelengths of the reflected waves. In the formula, i represents the measurement point number. The maximum wavelength. This is the minimum wavelength. The transfer coefficients for the displacement and wavelength conversion model; The compressive strength of coal seams and rock strata Cohesion internal friction angle And the parameters of the roadway burial depth h are used as variables, and the mining distance is... As input, a deep learning regression model was established to test the deformation of the surrounding rock in the roadway as a function of the mining distance. Substitute the actual mining distance and the measured displacement value into the function. The predicted displacement values ​​of the surrounding rock in the roadway are calculated, where This indicates the output value of the surrounding rock displacement in the roadway. Indicates the weighting coefficient. Indicators of coal seams and rock strata include compressive strength. Cohesion internal friction angle and the tunnel depth h, The threshold parameter is used to identify unknown parameters using a swarm intelligence optimization algorithm. By substituting the unknown parameters into a deep learning regression model, the model is used to predict the displacement of the surrounding rock in roadways at different mining distances. If the predicted displacement values ​​of the surrounding rock in the roadways are... Exceeding the threshold If so, an alarm will be triggered.

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