A device and method for determining grouting effect in a coal mine underground

Abstract

The application discloses a device and method for judging grouting effect in a coal mine, comprising a data acquisition device, a supporting mechanism and a data processing device; a three-dimensional hole wall graph is obtained by shooting the inside of a drill hole through a wide-angle camera, if the three-dimensional hole wall graph obtained in the shooting process exists an obstruction, it indicates that there is a pollutant on the surface of the anti-fouling cover, the remote control rotating shell is closed and is cleaned by flushing, so that the wide-angle camera can continuously shoot a clear three-dimensional hole wall graph, thereby the data can be accurately collected; in addition, the application first obtains the porosity from shallow to deep before grouting, then when the grouting area is detected, the hole wall planar graph of the current detection drill hole at different depth positions is obtained, after image segmentation processing, the residual porosity and the slurry filling rate at different depth positions can be obtained, finally the grouting effect at each depth position is determined through comparative analysis, and then the grouting effect evaluation at different depths can be obtained.

Description

Technical Field

[0001] This invention relates to a device and method for determining the effect of grouting in underground coal mines, belonging to the field of mine fire prevention and extinguishing grouting technology. Background Technology

[0002] Spontaneous combustion of coal in goaf areas is a key concern in mine fire prevention. Various fire prevention and extinguishing measures have been developed in the industry, among which grouting is the most commonly used. The effectiveness of grouting plays a crucial role in preventing spontaneous combustion of coal in goaf areas. However, due to the complex internal structure of goaf areas, it is difficult to accurately determine the effectiveness of grouting.

[0003] Currently, mining borehole inspection devices can be used to deeply observe the borehole walls in the grouting area, acquiring real-time morphology of the borehole inner wall and analyzing the grouting effect. Chinese invention patent CN102003191A discloses a method for judging the effect of curtain grouting in mines, which makes a real-time judgment on the overall grouting effect based on changes in grouting volume and pressure. However, it cannot judge the changes in grouting effect in different areas from shallow to deep (i.e., from the periphery to the interior of the grouting area). Chinese invention patent CN112813958A discloses a method and system for monitoring grouting effect on the ground, which evaluates the grouting effect by pre-deploying multiple microseismic detectors on the surface of the stratum requiring grouting and comparing microseismic events before and after grouting. However, its judgment is not accurate enough and cannot determine the grouting effect in real-time on-site.

[0004] In summary, existing methods for determining grouting effectiveness still have the following shortcomings: ① The data obtained for determining grouting effectiveness is not accurate enough; ② It is impossible to quickly and in real time analyze and process the grouting effectiveness; ③ When determining grouting effectiveness, it is impossible to achieve dynamic analysis of grouting effect changes in different areas from shallow to deep, and ultimately it is impossible to carry out targeted treatment measures for different areas. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a device and method for determining the grouting effect in underground coal mines. It can accurately collect data for determining the grouting effect, thereby quickly and in real time determining the grouting effect. It can also realize dynamic analysis of the grouting effect changes in different areas from shallow to deep, facilitating targeted treatment measures for different areas.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a device for determining the grouting effect in underground coal mines, comprising a data acquisition device, a support mechanism, and a data processing device;

[0007] The support mechanism includes a support rod, which has an inlet hole, a return hole and a cable channel inside. The inlet hole and the return hole are parallel to the axis of the support rod and pass through both ends of the support rod. The cable channel is arranged along the axis and passes through both ends of the support rod.

[0008] The data acquisition device includes a wide-angle camera, a ring bulb, a support column, a dirt cover, a rotary motor, a protective housing, and a rotating shell. One end of the support column is fixedly connected to one end of the support rod. The wide-angle camera is connected to the other end of the support column via a universal joint and secured with locking bolts for adjusting the shooting direction of the wide-angle camera. The ring bulb is mounted on the outer surface of the wide-angle camera for supplemental lighting during shooting. The dirt cover is fixed to one end of the support rod and houses the wide-angle camera, ring bulb, and support column inside, preventing debris from affecting the wide-angle camera's shooting. The protective housing is located outside the dirt cover and is fixedly connected to one end of the support rod. Both the water inlet and outlet holes communicate with the interior of the protective housing. The protective housing has an opening to allow the wide-angle camera to... The head is exposed to the outside through an opening; there are two rotating shells and two rotating motors. The two rotating shells are symmetrically arranged inside the protective shells on both sides of the anti-fouling cover. The two rotating motors are symmetrically fixed to the protective shells. The connecting shafts of the rotating motors are provided with protrusions. One side of each rotating shell is fixed to the protrusion of one of the rotating motors' connecting shafts, and the other side is provided with a through hole. The other side of the rotating shell is fitted onto the connecting shaft of the other rotating motor through the through hole. When the rotating motor fixed to the protrusion rotates, it can drive the rotating shell to rotate synchronously. The two rotating shells are fixed to different rotating motors with different protrusions. When it is necessary to close the protective shell, one rotating motor rotates in the forward direction and the other rotating motor rotates in the reverse direction, driving the two rotating shells to rotate towards each other to achieve a closed seal.

[0009] The data processing device includes a shooting screen, a data processor, and an imaging display screen. The data processor connects to the wide-angle camera, the ring bulb, and the rotary motor through a cable channel to acquire image data captured by the wide-angle camera and control the ring bulb and the rotary motor. The data processor displays the acquired image data in real time through the shooting screen and displays the processing results through the imaging display screen after analyzing and processing the image data.

[0010] Furthermore, the diameter of both the water inlet and the return water outlet is 10mm.

[0011] Furthermore, the rotary motor is a waterproof motor.

[0012] Furthermore, the cleaning agent in the water inlet and outlet is glass cleaner.

[0013] Furthermore, the wide-angle camera has night vision capabilities, and the maximum wide-angle coverage during shooting is 120 degrees.

[0014] The working method of the above-mentioned device for determining the grouting effect in underground coal mines includes the following specific steps:

[0015] Step 1: Based on the depth of the grouting holes designed on site and the expected grouting volume, determine the approximate range of the grouting impact, and then determine the depth of the detection borehole; and assemble the device used to determine the grouting effect in underground coal mines.

[0016] Step Two: Before grouting, drill a probe borehole in the non-grouting section. Then, insert the data acquisition device and support device assembled in Step One into the probe borehole. Use the data processor to control the ring lamp for supplemental lighting. As the data acquisition device penetrates deeper into the probe borehole, a wide-angle camera captures a 3D borehole wall image at predetermined intervals, displaying it on a screen. This process continues until the data acquisition device reaches the deepest point of the probe borehole. All acquired 3D borehole wall images are stored in the data processor. The data processor then unfolds all the 3D borehole wall images into planar images and processes them using binarization to obtain a binary image. Based on an adaptive binarization algorithm, the porosity of the planar image at each depth of the probe borehole is calculated as A. i The porosity of the borehole was compared and analyzed from shallow to deep to obtain the porosity change curve. The data results of the comparison and analysis were displayed on the imaging screen in real time.

[0017] Step 3: During the data acquisition process, when the data acquisition device is inserted into the borehole, an obstruction is detected in a certain 3D borehole wall image on the camera screen, indicating the presence of contaminants on the surface of the anti-fouling cover. At this point, the data processor controls two rotary motors to rotate, causing the two rotating shells to rotate in opposite directions. This is observed on the camera screen until the two rotating shells close the opening of the protective shell. The rotary motors then stop operating. Next, a water pump pumps cleaning agent into the inlet hole. The cleaning agent enters the interior of the protective shell through the inlet hole and washes the surface of the anti-fouling cover, causing the contaminants to separate from the surface of the anti-fouling cover. The contaminants are then discharged from the borehole through the return hole along with the rinsed cleaning agent. After rinsing for a period of time, the water pump is turned off, and the two rotary motors are controlled to rotate independently, causing the two rotating shells to reset. The camera screen is then used to observe whether there are contaminants on the surface of the anti-fouling cover at this time. If there are, the above impact cleaning process is repeated; otherwise, the data acquisition process continues.

[0018] Step 4: Grout the required grouting area using the grouting hole depth and expected grouting volume designed in Step 1. After the grouting work is completed and stabilized, divide the grouting area into multiple sections. Drill a probe borehole, identical to the one in Step 2, at the midpoint between two grouting holes near the center of each section. Repeat steps 2 and 3 for this probe borehole to obtain planar views of the borehole wall at different depths. Perform image segmentation on each planar view to obtain the remaining porosity B at different depths.i and grout filling rate C i The remaining porosity and grout filling rate of the borehole were compared and analyzed from shallow to deep images, and the variation curves of the remaining porosity and grout filling rate were obtained. The data results were then displayed in real time on the imaging screen. The grouting effect of this section from shallow to deep was evaluated using the two curves.

[0019] ① First, the porosity A of the non-grouting area is... i Residual porosity B at the same depth as this section i For comparison, if the porosity A at the same depth... i With residual porosity B i The difference L i If the porosity does not exceed 60%, proceed to step ②; otherwise, the grouting effect at this depth is considered poor, and proceed to step ③.

[0020] ② Calculate the remaining porosity B at this depth. i B i and grouting filling rate C i The ratio T of the sums i If the value is less than 0.3, it indicates that the grouting effect at that depth is good, and proceed to step ③; otherwise, it indicates that the grouting effect at that depth is poor, and proceed to step ③.

[0021] ③ Repeat steps ① and ② for different depths in the section from shallow to deep to obtain the grouting effect evaluation at different depths. If the proportion of good grouting effect in each different depth position exceeds 80%, it indicates that the overall grouting effect of the section is good; otherwise, it is judged that the overall grouting effect of the section is poor.

[0022] Step 5: Select another section within the grouting area and repeat Step 4. Then, obtain the grouting effect evaluation of the current section from shallow to deep. Repeat this process multiple times until the grouting effect evaluation of all sections from shallow to deep is completed. This achieves a comprehensive evaluation of the grouting effect at different locations within the grouting area. Based on the evaluation results, it is determined whether supplementary grouting measures should be taken for each section. For example, if the overall grouting effect evaluation of a certain section is poor, then the parts with poor grouting effect at each depth in that section are selected for targeted secondary grouting to ensure the grouting effect after supplementary grouting.

[0023] Furthermore, in step four, image segmentation processing is performed on each planar image to segment the image, specifically as follows:

[0024] S1: Preprocess one of the planar images to obtain a grayscale histogram image, divide the image into L grayscale levels, i.e., 1, 2, 3, ..., L, and let n be the number of pixels in the i-th grayscale level. iThen we obtain the total number of pixels N and the probability distribution p of each gray level. i :

[0025]

[0026] S2: Let k1 and k2 be the thresholds for dividing the three regions of slurry, residual pores, and coal wall, so that the probability w of the occurrence of the three regions can be obtained. i Average gray level u i And the average gray level u of the original plan view T :

[0027] w3 = 1 - w1 - w2;

[0028] u3 = 1 - u1 - u2;

[0029] Where w1 represents the probability of the slurry region appearing, w2 represents the probability of the remaining pore region appearing, and w3 represents the probability of the coal wall appearing; u1 represents the average gray level of the slurry region, u2 represents the average gray level of the remaining pore region, and u3 represents the average gray level of the coal wall.

[0030] S3: Calculate the inter-class difference σ according to the following formula. 2 B By iterating through k1 and k2, the maximum inter-class variance σ is found. 2 B (As long as the inter-class variance σ is guaranteed) 2 B (If maximized, it can achieve the division of three regions):

[0031]

[0032] S4: After iterative calculation, return outputs k1 and k2 such that σ 2 B Keeping the maximum value, the current planar image is segmented using thresholds k1 and k2 to obtain the slurry region, the remaining porosity region, and the coal wall region. These three regions are then displayed in white, gray, and black, respectively. Finally, w1 and w2 are returned on the imaging display screen as the remaining porosity B of the current planar image. i and grouting filling rate C i ;

[0033] S5: Repeat steps S1 to S4 sequentially for the remaining planar map to obtain the remaining porosity B at different depth locations. i and grout filling rate C i .

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] 1. This invention uses a wide-angle camera to capture images of the borehole to obtain a three-dimensional borehole wall image. Because the wide-angle camera is equipped with a dustproof cover, it prevents impurities inside the borehole from contaminating the camera itself, ensuring clear images are captured. If obstructions are present in the three-dimensional borehole wall image acquired during the capture process, it indicates the presence of contaminants on the surface of the dustproof cover. In this case, there is no need to remove the device from the borehole. The rotating shell can be closed remotely and rinsed to clean the dustproof cover. After cleaning, the borehole capture process can continue. This ensures that the wide-angle camera continuously captures clear three-dimensional borehole wall images, thereby accurately collecting data to determine the grouting effect.

[0036] 2. This invention obtains the porosity A at various locations from shallow to deep before grouting. i Then, during subsequent drilling to explore the grouting area, the borehole wall planar images at different depths of the current borehole are obtained. After image segmentation processing, the remaining porosity B at different depths can be obtained. i and grout filling rate C i Finally, by comparing and analyzing the residual porosity B of the ungrouted area and the grouted area at the same depth, i Grout filling rate C i and porosity A i By using multiple judgment criteria, the grouting effect at a certain depth can be determined, thereby obtaining an evaluation of the grouting effect at different depths. Based on the evaluation, supplementary grouting can be carried out on areas with poor overall grouting effect. Therefore, this invention can quickly and in real time determine the grouting effect and can realize a comprehensive dynamic analysis of the changes in grouting effect in different areas from shallow to deep, which facilitates targeted treatment measures for different areas. Attached Figure Description

[0037] Figure 1 This is an overall layout diagram when the present invention is used;

[0038] Figure 2 This is a diagram showing the layout of the detection boreholes in a certain section of this invention;

[0039] Figure 3 This is a schematic diagram of the structure of the rotating shell in the present invention when it is not closed;

[0040] Figure 4 This is a schematic diagram of the structure of the rotating shell after it is closed in this invention;

[0041] Figure 5 for Figure 4 Top sectional view;

[0042] Figure 6 This is a schematic diagram of the rotary motor in this invention.

[0043] In the diagram: 1-Wide-angle camera, 2-Ring bulb, 3-Anti-fouling cover, 4-Locking bolt, 5-Rotating shell, 6-Rotating motor, 7-Water inlet, 8-Return water hole, 9-Support rod, 10-Cable, 11-Water pump, 12-Shooting screen, 13-Data processor, 14-Imaging display screen, 15-Grouting hole, 16-Detection borehole. Detailed Implementation

[0044] The present invention will be further described below.

[0045] like Figure 1 As shown, a device for determining the grouting effect in underground coal mines includes a data acquisition device, a support mechanism, and a data processing device.

[0046] The support mechanism includes a support rod 9, which has a water inlet hole 7, a water return hole 8 and a cable channel inside. The water inlet hole 7 and the water return hole 8 are parallel to the axis of the support rod 9 and both the water inlet hole 7 and the water return hole 8 pass through both ends of the support rod 9. The cable channel is arranged along the axis and passes through both ends of the support rod 9. The diameter of the water inlet hole 7 and the water return hole 8 is 10mm.

[0047] like Figures 3 to 5 As shown, the data acquisition device includes a wide-angle camera 1, a ring light bulb 2, a support column, a dirt cover 3, a rotary motor 6, a protective shell, and a rotating shell 5. The wide-angle camera 1 has night vision capabilities and covers a maximum wide angle of 120 degrees when shooting. One end of the support column is fixedly connected to one end of the support rod 9. The wide-angle camera 1 is connected to the other end of the support column via a universal joint and is secured and positioned by locking bolts, used to adjust the shooting direction of the wide-angle camera 1. The ring bulb 2 is mounted on the outer surface of the wide-angle camera 1 for supplemental lighting during shooting. The anti-fouling cover 3 is fixed to one end of the support rod 9 and covers the wide-angle camera 1, the ring bulb 2, and the support column inside it, used to prevent debris from affecting the shooting of the wide-angle camera 1. The protective shell is located outside the anti-fouling cover 3 and is fixedly connected to one end of the support rod 9. The water inlet 7 and the water outlet 8 are both connected to the inside of the protective shell. The protective shell has an opening, allowing the wide-angle camera 1 to shoot to the outside through the opening. There are two rotating shells 5 and two rotating motors 6. The two rotating shells 5 are symmetrically arranged inside the protective shell on both sides of the anti-fouling cover 3, and the two rotating motors 6 are symmetrically fixed on the protective shell. Figure 6As shown, the connecting shaft of the rotary motor 6 has a protrusion. One side of each of the two rotating shells 5 is fixed to the protrusion of the connecting shaft of one of the rotary motors 6, and the other side has a through hole. The other side of the rotating shell 5 is fitted onto the connecting shaft of the other rotary motor 6 through the through hole. When the rotary motor 6 fixed to the protrusion rotates, it can drive the rotating shell 5 to rotate synchronously. The two rotating shells 5 are fixed to different rotary motors 6 with different protrusions. When it is necessary to seal the protective shell, one rotary motor 6 rotates in the forward direction and the other rotary motor 6 rotates in the reverse direction, driving the two rotating shells 5 to rotate towards each other to achieve a closed seal. The rotary motor 6 is a waterproof motor.

[0048] The data processing device includes a shooting screen 12, a data processor 13, and an imaging display screen 14. The data processor 13 connects the cable 10 through the cable channel to the wide-angle camera 1, the ring bulb 2, and the rotary motor 6, and is used to acquire image data captured by the wide-angle camera 1 and control the ring bulb 2 and the rotary motor 6. The data processor 13 displays the acquired image data in real time through the shooting screen 12, and after analyzing and processing the image data, displays the processing results through the imaging display screen 14.

[0049] The working method of the above-mentioned device for determining the grouting effect in underground coal mines includes the following specific steps:

[0050] Step 1: Based on the depth of the grouting holes designed on site and the expected grouting volume, determine the approximate range of the grouting impact, and then determine the depth of the detection borehole 16; and assemble the device used to determine the grouting effect in underground coal mines.

[0051] Step Two: Before grouting, drill a 65mm diameter, 30m deep exploratory borehole in the non-grouting section. Then, insert the data acquisition device and support device assembled in Step One into the exploratory borehole 16. The data processor 13 controls the ring lamp 2 to provide supplemental lighting. As the data acquisition device penetrates deeper into the exploratory borehole 16, a 3D borehole wall image is acquired at set intervals using a wide-angle camera 1 and displayed on the imaging screen 12. This process continues until the data acquisition device reaches the deepest point of the exploratory borehole 16. All acquired 3D borehole wall images are stored in the data processor 13. The data processor 13 sequentially unfolds all 3D borehole wall images into planar images and then uses binarization to process the images, obtaining a binarized image. Based on the adaptive binarization algorithm, the porosity of the planar image at each depth position of the exploratory borehole 16 is calculated as A. i The porosity of the images of the borehole 16 from shallow to deep is compared and analyzed to obtain the porosity change curve. At the same time, the data results of the comparison and analysis are displayed on the imaging display screen 14 in real time.

[0052] Step 3: During the data acquisition process, when the data acquisition device is inserted into the probe borehole 16, an obstruction is detected in a certain three-dimensional hole wall image obtained through the imaging screen 12, indicating that there are contaminants on the surface of the anti-fouling cover 3. At this time, the data processor 13 controls the two rotary motors 6 to rotate, causing the two rotating shells 5 to rotate towards each other. The imaging screen 12 is used to observe until the two rotating shells 5 close the opening of the protective shell. The rotary motors 5 are then stopped. Then, a cleaning agent (glass cleaner) is pumped into the water inlet 7 through the water pump. The cleaning agent enters the interior of the protective shell through the water inlet 7 and washes the surface of the anti-fouling cover 3, causing the contaminants to separate from the surface of the anti-fouling cover 3. The contaminants are then discharged from the probe borehole 16 through the return water hole 8 along with the rinsed cleaning agent. After rinsing for a period of time, the water pump is turned off, and the two rotary motors 6 are controlled to rotate independently, causing the two rotating shells 5 to reset. The imaging screen 12 is used to observe whether there are contaminants on the surface of the anti-fouling cover 3 at this time. If there are, the above impact cleaning process is repeated. If there are no contaminants, the process of capturing and collecting data continues.

[0053] Step 4: Grout the required grouting area using the grouting hole depth and expected grouting volume designed in Step 1. After the grouting work is completed and stabilized, divide the grouting area into multiple sections, such as... Figure 2 As shown, a probe borehole 16, identical to that in step two, is drilled at the midpoint between two grouting holes 15 near the center of each section. After completion, steps two and three are repeated for this probe borehole 16 to obtain planar views of the borehole wall at different depths. Image segmentation is then performed on each planar view, specifically as follows:

[0054] S1: Preprocess one of the planar images to obtain a grayscale histogram image, divide the image into L grayscale levels, i.e., 1, 2, 3, ..., L, and let n be the number of pixels in the i-th grayscale level. i Then we obtain the total number of pixels N and the probability distribution p of each gray level. i :

[0055]

[0056] S2: Let k1 and k2 be the thresholds for dividing the three regions of slurry, residual pores, and coal wall, so that the probability w of the occurrence of the three regions can be obtained. i Average gray level u i And the average gray level u of the original plan view T :

[0057] w3 = 1 - w1 - w2;

[0058] u3 = 1 - u1 - u2;

[0059] Where w1 represents the probability of the slurry region appearing, w2 represents the probability of the remaining pore region appearing, and w3 represents the probability of the coal wall appearing; u1 represents the average gray level of the slurry region, u2 represents the average gray level of the remaining pore region, and u3 represents the average gray level of the coal wall.

[0060] S3: Calculate the inter-class difference σ according to the following formula. 2 B By iterating through k1 and k2, the maximum inter-class variance σ is found. 2 B (As long as the inter-class variance σ is guaranteed) 2 B (If maximized, it can achieve the division of three regions):

[0061]

[0062] S4: After iterative calculation, return outputs k1 and k2 such that σ 2 B Keeping the maximum value, the current planar image is segmented using thresholds k1 and k2 to obtain the slurry region, the remaining porosity region, and the coal wall region. These three regions are then displayed in white, gray, and black, respectively. Finally, w1 and w2 are returned on the imaging display screen as the remaining porosity B of the current planar image. i and grouting filling rate C i ;

[0063] S5: Repeat steps S1 to S4 sequentially for the remaining planar map to obtain the remaining porosity B at different depth locations. i and grout filling rate C i .

[0064] By comparing and analyzing the residual porosity and grout filling rate of images from shallow to deep borehole 16, the variation curves of residual porosity and grout filling rate are obtained. Simultaneously, the data results are displayed in real-time on the imaging display screen 14. The grouting effect of this section from shallow to deep is evaluated using these two curves.

[0065] ① First, the porosity A of the non-grouting area is... i Residual porosity B at the same depth as this section i For comparison, if the porosity A at the same depth... i With residual porosity B i The difference L i If the porosity does not exceed 60%, proceed to step ②; otherwise, the grouting effect at this depth is considered poor, and proceed to step ③.

[0066] ② Calculate the remaining porosity B at this depth. i B i and grouting filling rate Ci The ratio T of the sums i If the value is less than 0.3, it indicates that the grouting effect at that depth is good, and proceed to step ③; otherwise, it indicates that the grouting effect at that depth is poor, and proceed to step ③.

[0067] ③ Repeat steps ① and ② for different depths in the section from shallow to deep to obtain the grouting effect evaluation at different depths. If the proportion of good grouting effect in each different depth position exceeds 80%, it indicates that the overall grouting effect of the section is good; otherwise, it is judged that the overall grouting effect of the section is poor.

[0068] Step 5: Select another section in the grouting area and repeat Step 4 to obtain the grouting effect evaluation of the current section from shallow to deep. Repeat this process multiple times until the grouting effect evaluation of all sections from shallow to deep is completed. This will enable a comprehensive evaluation of the grouting effect at different locations in the grouting area and determine whether to implement supplementary grouting measures for each section based on the evaluation results.

[0069] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A device for determining the grouting effect in underground coal mines, characterized in that, Includes data acquisition devices, support structures, and data processing devices; The support mechanism includes a support rod, which has an inlet hole, a return hole and a cable channel inside. The inlet hole and the return hole are parallel to the axis of the support rod and pass through both ends of the support rod. The cable channel is arranged along the axis and passes through both ends of the support rod. The data acquisition device includes a wide-angle camera, a ring bulb, a support column, a dirt cover, a rotary motor, a protective housing, and a rotating shell. One end of the support column is fixedly connected to one end of the support rod. The wide-angle camera is connected to the other end of the support column via a universal joint and secured with locking bolts for adjusting the shooting direction of the wide-angle camera. The ring bulb is mounted on the outer surface of the wide-angle camera for supplemental lighting during shooting. The dirt cover is fixed to one end of the support rod and houses the wide-angle camera, ring bulb, and support column inside, preventing debris from affecting the wide-angle camera's shooting. The protective housing is located outside the dirt cover and is fixedly connected to one end of the support rod. Both the water inlet and outlet holes communicate with the interior of the protective housing. The protective housing has an opening to allow the wide-angle camera to... The head is exposed to the outside through an opening; there are two rotating shells and two rotating motors. The two rotating shells are symmetrically arranged inside the protective shells on both sides of the anti-fouling cover. The two rotating motors are symmetrically fixed to the protective shells. The connecting shafts of the rotating motors are provided with protrusions. One side of each rotating shell is fixed to the protrusion of one of the rotating motors' connecting shafts, and the other side is provided with a through hole. The other side of the rotating shell is fitted onto the connecting shaft of the other rotating motor through the through hole. When the rotating motor fixed to the protrusion rotates, it can drive the rotating shell to rotate synchronously. The two rotating shells are fixed to different rotating motors with different protrusions. When it is necessary to close the protective shell, one rotating motor rotates in the forward direction and the other rotating motor rotates in the reverse direction, driving the two rotating shells to rotate towards each other to achieve a closed seal. The data processing device includes a shooting screen, a data processor, and an imaging display screen. The data processor connects to the wide-angle camera, the ring bulb, and the rotary motor through a cable channel to acquire image data captured by the wide-angle camera and control the ring bulb and the rotary motor. The data processor displays the acquired image data in real time through the capture screen, and after analyzing and processing the image data, displays the processing results through the imaging display screen.

2. The device for determining the grouting effect in underground coal mines according to claim 1, characterized in that, The diameter of both the water inlet and the return water outlet is 10mm.

3. The device for determining the grouting effect in underground coal mines according to claim 1, characterized in that, The rotary motor is a waterproof motor.

4. The device for determining the grouting effect in underground coal mines according to claim 1, characterized in that, The cleaning agent in the water inlet and outlet is glass cleaner.

5. The device for determining the grouting effect in underground coal mines according to claim 1, characterized in that, The wide-angle camera has night vision capabilities and covers a maximum angle of 120 degrees when shooting.

6. A method for operating the device for determining the grouting effect in underground coal mines according to any one of claims 1 to 5, characterized in that, The specific steps are as follows: Step 1: Based on the depth of the grouting holes designed on site and the expected grouting volume, determine the approximate range of the grouting impact, and then determine the depth of the detection borehole; and assemble the device used to determine the grouting effect in underground coal mines. Step Two: Before grouting, drill a probe borehole in the non-grouting section. Then, insert the data acquisition device and support device assembled in Step One into the probe borehole. Use the data processor to control the ring lamp for supplemental lighting. As the data acquisition device penetrates deeper into the probe borehole, a wide-angle camera captures a 3D borehole wall image at predetermined intervals, displaying it on a screen. This process continues until the data acquisition device reaches the deepest point of the probe borehole. All acquired 3D borehole wall images are stored in the data processor. The data processor then unfolds all the 3D borehole wall images into planar images and processes them using binarization to obtain a binary image. Based on an adaptive binarization algorithm, the porosity of the planar image at each depth of the probe borehole is calculated as A. i The porosity of the borehole was compared and analyzed from shallow to deep to obtain the porosity change curve. The data results of the comparison and analysis were displayed on the imaging screen in real time. Step 3: During the data acquisition process, when the data acquisition device is inserted into the borehole, an obstruction is detected in a certain 3D borehole wall image on the camera screen, indicating the presence of contaminants on the surface of the anti-fouling cover. At this point, the data processor controls two rotary motors to rotate, causing the two rotating shells to rotate in opposite directions. This is observed on the camera screen until the two rotating shells close the opening of the protective shell. The rotary motors then stop operating. Next, a water pump pumps cleaning agent into the inlet hole. The cleaning agent enters the interior of the protective shell through the inlet hole and washes the surface of the anti-fouling cover, causing the contaminants to separate from the surface of the anti-fouling cover. The contaminants are then discharged from the borehole through the return hole along with the rinsed cleaning agent. After rinsing for a period of time, the water pump is turned off, and the two rotary motors are controlled to rotate independently, causing the two rotating shells to reset. The camera screen is then used to observe whether there are contaminants on the surface of the anti-fouling cover at this time. If there are, the above impact cleaning process is repeated; otherwise, the data acquisition process continues. Step 4: Grout the required grouting area using the grouting hole depth and expected grouting volume designed in Step 1. After the grouting work is completed and stabilized, divide the grouting area into multiple sections. Drill a probe borehole, identical to the one in Step 2, at the midpoint between two grouting holes near the center of each section. Repeat steps 2 and 3 for this probe borehole to obtain planar views of the borehole wall at different depths. Perform image segmentation on each planar view to obtain the remaining porosity B at different depths. i and grout filling rate C i And compare and analyze the probe The residual porosity and grout filling rate were measured in images from shallow to deep boreholes, and curves showing the variation of each were obtained. The comparative analysis data was then displayed in real-time on an imaging screen. The grouting effect in this section from shallow to deep was evaluated using these two curves. ① First, the porosity A of the non-grouting area is... i Residual porosity B at the same depth as this section i For comparison, if the porosity A at the same depth... i With residual porosity B i The difference L i If the porosity does not exceed 60%, proceed to step ②; otherwise, the grouting effect at this depth is considered poor, and proceed to step ③. ② Calculate the remaining porosity B at this depth. i B i and grouting filling rate C i The ratio T of the sums i If the value is less than 0.3, it indicates that the grouting effect at that depth is good, and proceed to step ③; otherwise, it indicates that the grouting effect at that depth is poor, and proceed to step ③. ③ Repeat steps ① and ② for different depths in the section from shallow to deep to obtain the grouting effect evaluation at different depths. If the proportion of good grouting effect in each different depth position exceeds 80%, it indicates that the overall grouting effect of the section is good; otherwise, it is judged that the overall grouting effect of the section is poor. Step 5: Select another section in the grouting area and repeat Step 4 to obtain the grouting effect evaluation of the current section from shallow to deep. Repeat this process multiple times until the grouting effect evaluation of all sections from shallow to deep is completed. This will enable a comprehensive evaluation of the grouting effect at different locations in the grouting area and determine whether to implement supplementary grouting measures for each section based on the evaluation results.

7. The working method of the device for determining the grouting effect in underground coal mines according to claim 6, characterized in that, In step four, image segmentation is performed on each planar image; specifically: S1: Preprocess one of the planar images to obtain a grayscale histogram image, divide the image into L grayscale levels, i.e., 1, 2, 3, ..., L, and let n be the number of pixels in the i-th grayscale level. i Then we obtain the total number of pixels N and the probability distribution p of each gray level. i : S2: Let k1 and k2 be the thresholds for dividing the three regions of slurry, residual pores, and coal wall, so that the probability w of the occurrence of the three regions can be obtained. i Average gray level u i And the average gray level u of the original plan view T : w3=1-w1-w2; u3 = 1 - u1 - u2; Where w1 represents the probability of the slurry region appearing, w2 represents the probability of the remaining pore region appearing, and w3 represents the probability of the coal wall appearing; u1 represents the average gray level of the slurry region, u2 represents the average gray level of the remaining pore region, and u3 represents the average gray level of the coal wall. S3: Calculate the inter-class difference σ according to the following formula. 2 B By iterating through k1 and k2, the maximum inter-class variance σ is found. 2 B : S4: After iterative calculation, return outputs k1 and k2 such that σ 2 B Keeping the maximum value, the current planar image is segmented using thresholds k1 and k2 to obtain the slurry region, the remaining porosity region, and the coal wall region. These three regions are then displayed in white, gray, and black, respectively. Finally, w1 and w2 are returned on the imaging display screen as the remaining porosity B of the current planar image. i and grouting filling rate C i ; S5: Repeat steps S1 to S4 sequentially for the remaining planar map to obtain the remaining porosity B at different depth locations. i and grout filling rate C i .

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