Detection device and detection method for detecting depth of damaged zone of bottom plate

Abstract

The invention provides a detection device and method for detecting the depth of a damaged zone of a bottom plate, and the device comprises a temperature sensing optical cable which is used for measuring the temperature in a detection hole, and is provided with a plurality of temperature measurement points at equal intervals in the length direction; the liquid injection pipe and the temperature sensing optical cable are arranged side by side, and the liquid injection pipe is used for injecting liquid into the detection hole; and the processor is electrically connected with the temperature sensing optical cable and calculates the depth of the bottom plate damage zone according to detection data of the temperature sensing optical cable. According to the technical scheme, the problems that in the prior art, when the depth of the damaged zone of the bottom plate is detected, the detection work difficulty is large, and the detection efficiency is low can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel damage zone detection, and in particular to a detection device and a detection method for detecting the depth of a bottom plate damage zone. Background Art

[0002] During coal mining, the coal seam floor rock strata form a floor water-conducting destruction zone, an effective aquiclude protection zone (or complete rock strata zone) and a confined water conduction zone from top to bottom. The floor water-conducting destruction zone refers to a layer where the continuity of the floor rock strata is destroyed and the water conductivity is significantly changed due to the mining pressure; the effective aquiclude protection zone is a rock stratum that maintains the continuity of the rock strata before mining and its water resistance performance, also known as the complete rock stratum zone; the confined water conduction zone refers to the height to which the confined water in the aquifer rises along the cracks or fracture zones in the impermeable floor.

[0003] In the field of coal mining, with the gradual depletion of shallow coal resources, the mining of deep coal resources has become an inevitable trend. However, deep mining faces a more complex geological environment, especially the threat of pressurized water in the floor limestone, which greatly increases the risk of water inrush in the mine. In order to safely and efficiently utilize deep coal resources, accurately grasping the damage characteristics of the floor rock layer during coal seam mining, especially the depth of the damage zone, has become a key issue that needs to be solved urgently.

[0004] At present, existing testing technologies such as optical cable strain monitoring and electrical monitoring data require technicians to have high professional capabilities. The interpretation of the monitoring data increases the difficulty of work. The complexity of data processing and analysis algorithms makes it difficult for coal mine technicians to apply them, making the detection work difficult and the detection efficiency low when detecting the depth of the damage zone. Summary of the invention

[0005] The present invention provides a detection device and a detection method for detecting the depth of a bottom plate damage zone, so as to solve the problems of great difficulty in detecting the depth of a bottom plate damage zone and low detection efficiency in the prior art.

[0006] According to one aspect of the present invention, there is provided a detection device for detecting the depth of the bottom plate damage zone, the detection device comprising: a temperature-sensitive optical cable, for measuring the temperature in a detection hole, the temperature-sensitive optical cable having a plurality of temperature measuring points equally spaced along the length direction; a liquid injection tube, arranged side by side with the temperature-sensitive optical cable, the liquid injection tube being used to inject liquid into the detection hole; a processor, electrically connected to the temperature-sensitive optical cable, the processor calculating the depth of the bottom plate damage zone according to the detection data of the temperature-sensitive optical cable.

[0007] Furthermore, the detection device also includes a protective tube, which is sleeved on the outside of the temperature-sensitive optical cable. The protective tube is provided with a connecting hole, which is used to communicate with the detection hole so that the liquid in the injection tube can flow into the protective tube.

[0008] Furthermore, the protective tube and the injection tube are fixedly connected side by side, and the detection device also includes a guide head, which is jointly mounted on one end of the protective tube located at the detection hole and one end of the injection tube located at the detection hole, and the cross-sectional size of the guide head gradually decreases from the direction toward the bottom of the detection hole.

[0009] Furthermore, the protection tube has a plurality of connecting holes, which are evenly distributed on the side wall of the protection tube, and the injection tube has a plurality of injection holes, which are evenly distributed on the side wall of one end of the injection tube located in the detection hole.

[0010] Furthermore, a flow meter and a control valve are provided on one end of the injection pipe away from the detection hole. The control valve is located downstream of the flow meter. The flow meter is used to detect the water injection volume of the injection pipe. The flow meter is electrically connected to the processor. The processor calculates the depth of the bottom plate damage zone based on the data from the temperature sensing optical cable and the flow meter.

[0011] According to another aspect of the present invention, a detection method for detecting the depth of the bottom plate damage zone is provided. The detection method is applied to the above-mentioned detection device, and the detection method comprises: drilling a detection hole on the bottom plate of the goaf area of ​​the tunnel; passing one end of the temperature-sensitive optical cable and one end of the injection tube of the detection device into the bottom of the detection hole, continuously injecting liquid into the detection hole through the injection tube, and obtaining temperature data to be measured along the length direction through the temperature-sensitive optical cable; judging whether the liquid level in the detection hole is in the damage zone according to the temperature data to be measured, and if it is in the damage zone, the processor of the detection device calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length of two adjacent temperature measuring points.

[0012] Furthermore, the processor calculates the depth of the bottom plate damage zone based on the measured temperature data and the length of the interval between two adjacent temperature measuring points, specifically including: obtaining the measured temperature data during the water injection period and the measured flow rate of the flow meter; obtaining the measured water injection volume per unit height based on the measured temperature data, the length of the interval between two adjacent temperature measuring points and the measured flow rate; judging whether the liquid level in the detection hole is in the damage zone based on the measured temperature data and the measured flow rate, and if so, obtaining the flow data of the liquid level, and calculating the depth of the bottom plate damage zone based on the flow data and the measured water injection volume.

[0013] Furthermore, judging whether the liquid level in the detection hole is in the damage zone is performed based on the measured temperature data and the measured flow rate, specifically comprising: obtaining a length-flow curve based on the measured temperature data and the measured flow rate; wherein, if the growth rate of the injection volume per unit length corresponding to a certain length on the length-flow curve is greater than or equal to 30%, then the liquid level corresponding to this length is in the damage zone.

[0014] Furthermore, the tunnel also has a waiting area for mining. Before judging whether the liquid level in the detection hole is in the damage zone according to the temperature data, the detection method also includes: drilling a control hole on the bottom plate of the waiting area for mining; passing one end of the temperature-sensitive optical cable and one end of the injection tube of the detection device of the control group to the bottom of the control hole, continuously injecting liquid into the control hole through the injection tube, and obtaining control temperature data along the length direction through the temperature-sensitive optical cable; obtaining control temperature data during the water injection period and control flow of the flow meter; obtaining a control water injection volume per unit height according to the control temperature data, the interval length of two adjacent temperature measuring points and the control flow; judging whether the detection hole is completely in the damage zone according to the comparison of the control water injection volume per unit height and the water injection volume to be measured per unit height. If the detection hole is completely in the damage zone, it is necessary to drill the detection hole again; if the detection hole is partially in the damage zone, the depth of the damage zone continues to be calculated.

[0015] Furthermore, based on the comparison between the control water injection volume per unit height and the water injection volume to be tested per unit height, it is judged whether the detection hole is completely in the damage zone, specifically including: if the water injection volume to be tested per unit height is greater than or equal to 1.3 times the control water injection volume per unit height, then it is judged that the detection hole is completely in the damage zone.

[0016] By applying the technical solution of the present invention, liquid is injected into the detection hole through the injection pipe, and multiple temperature measuring points on the temperature-sensitive optical cable sense the ambient temperature or the temperature of the injected liquid. Since there is an obvious temperature difference between the ambient temperature and the temperature of the injected liquid, the processor can obtain the liquid level information of different temperature measuring points in the detection hole through the temperature data of the temperature-sensitive optical cable to calculate the depth of the bottom plate damage zone. Through the above setting, the depth of the damage zone is calculated using the temperature measured by the temperature measuring point on the temperature-sensitive optical cable and the liquid level height information in the detection hole obtained by the processor analysis. The detection method is simple and does not require complex calculations, so that the detection work difficulty is reduced when detecting the depth of the damage zone, and the detection efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A partial structural schematic diagram of a detection device provided according to an embodiment of the present invention is shown;

[0019] Figure 2 A schematic diagram showing a detection drilling arrangement provided according to an embodiment of the present invention is shown;

[0020] Figure 3 A cross-sectional schematic diagram of a detection device provided according to an embodiment of the present invention detecting a borehole is shown.

[0021] The above drawings include the following reference numerals:

[0022] 10. Temperature sensing optical cable;

[0023] 20. Liquid injection tube;

[0024] 30. Processor;

[0025] 40. Protective tube;

[0026] 50. Guide head;

[0027] 60. Flow meter;

[0028] 70. Control valve;

[0029] 80. Goaf;

[0030] 90. Area to be mined;

[0031] 100. Stop mining line;

[0032] 110. Upper chute;

[0033] 120. Down the chute. DETAILED DESCRIPTION

[0034] 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, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. 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.

[0035] like Figures 1 to 3 As shown, an embodiment of the present invention provides a detection device for detecting the depth of the bottom plate damage zone, the detection device comprising: a temperature-sensitive optical cable 10, an injection tube 20 and a processor 30, wherein the temperature-sensitive optical cable 10 is used to measure the temperature in the detection hole, and the temperature-sensitive optical cable 10 has a plurality of temperature measuring points evenly spaced along the length direction; the injection tube 20 is arranged side by side with the temperature-sensitive optical cable 10, and the injection tube 20 is used to inject liquid into the detection hole; the processor 30 is electrically connected to the temperature-sensitive optical cable 10, and the processor 30 calculates the depth of the bottom plate damage zone according to the detection data of the temperature-sensitive optical cable 10.

[0036] By applying the technical solution of the present invention, liquid is injected into the detection hole through the injection pipe 20, and multiple temperature measuring points on the temperature-sensitive optical cable 10 sense the ambient temperature or the temperature of the injected liquid. Since there is an obvious temperature difference between the ambient temperature and the temperature of the injected liquid, the processor 30 can obtain the liquid level information of different temperature measuring points in the detection hole through the temperature data of the temperature-sensitive optical cable 10 to calculate the depth of the bottom plate damage zone. Through the above-mentioned setting, the depth of the damage zone is calculated using the temperature measured by the temperature measuring point on the temperature-sensitive optical cable 10 and the liquid level height information in the detection hole analyzed by the processor 30. The detection method is simple and does not require complex calculations, so that the detection work difficulty is reduced when detecting the depth of the damage zone, and the detection efficiency is improved.

[0037] Furthermore, the detection device also includes a protective tube 40, which is sleeved on the outside of the temperature-sensitive optical cable 10, and a connecting hole is provided on the protective tube 40, and the connecting hole is used to communicate with the detection hole so that the liquid in the injection tube 20 can flow into the protective tube 40. Through the above-mentioned arrangement, the protective tube 40 is sleeved on the outside of the temperature-sensitive optical cable 10, which can provide mechanical protection for the temperature-sensitive optical cable 10, prevent the optical cable from being physically damaged when entering the detection hole, and also make the installation and maintenance of the temperature-sensitive optical cable 10 more convenient. In addition, a connecting hole is provided on the protective tube 40, and the connecting hole is connected with the detection hole so that the liquid in the injection tube 20 can flow into the protective tube 40, so that the temperature-sensitive optical cable 10 in the protective tube 40 can detect the temperature change in the detection hole, so that the processor 30 can obtain the liquid level information in the detection hole.

[0038] In other embodiments of the present application, a temperature-sensitive optical cable gravity guide sinker is provided near the bottom of the detection hole of the temperature-sensitive optical cable 10, which can ensure that the temperature-sensitive optical cable 10 remains straight during the process of entering the detection hole, avoid bending of the temperature-sensitive optical cable 10, and ensure stable and reliable performance of the temperature-sensitive optical cable 10. In addition, the gravity guide sinker can also simplify the installation process of the temperature-sensitive optical cable 10, making it easier to guide and fix the temperature-sensitive optical cable 10 at a predetermined position, and also facilitate subsequent maintenance work.

[0039] Specifically, the protection tube 40 is fixedly connected side by side with the injection tube 20, and the detection device further includes a guide head 50, which is sleeved on one end of the protection tube 40 located at the detection hole and one end of the injection tube 20 located at the detection hole, and the cross-sectional size of the guide head 50 gradually decreases from the direction toward the bottom of the detection hole. In the embodiment of the present application, the protection tube 40 and the injection tube 20 are fixedly connected side by side through a plurality of double-tube fixing clips, and the installation operation of the double-tube fixing clips is simple, convenient and quick.

[0040] In addition, the guide head 50 is sleeved on one end of the protective tube 40 and the injection tube 20 located in the detection hole. In the process of the protective tube 40 and the injection tube 20 passing through the detection hole, the guide head 50 can reduce the friction between part of the pipe and the hole wall, thereby reducing the risk of damage to the pipe. The hardness of the guide head 50 is higher than that of the protective tube 40 and the injection tube 20, and the cross-sectional size of the guide head 50 gradually decreases from the direction toward the bottom of the detection hole, which can help the protective tube 40 and the injection tube 20 to enter the detection hole smoothly. In particular, when there is a crack in the detection hole, the protective tube 40 and the injection tube 20 may be stuck. The guide head 50 can enable the double tubes to reach the bottom of the detection hole smoothly.

[0041] Among them, the protection tube 40 has a plurality of connecting holes, and the plurality of connecting holes are evenly distributed on the side wall of the protection tube 40, and the injection tube 20 has a plurality of injection holes, and the plurality of injection holes are evenly distributed on the side wall of one end of the injection tube 20 located in the detection hole. Through the above arrangement, the plurality of injection holes evenly distributed on the side wall of the one end of the injection tube 20 located in the detection hole allow the liquid in the injection tube 20 to flow into the detection hole through the plurality of injection holes, and part of the liquid in the detection hole then flows into the protection tube 40 through the plurality of connecting holes of the protection tube 40, so that the temperature measuring point on the temperature-sensing optical cable 10 can sense the liquid temperature of this liquid level, so that it forms an obvious temperature change with the ambient temperature in the detection hole originally sensed, thereby allowing the processor 30 to record and obtain the liquid level information of the temperature measuring point.

[0042] In the embodiment of the present application, the liquid introduced into the injection tube 20 is water. In other implementations of the present application, other liquids that have a significant temperature change with the ambient temperature may also be used.

[0043] like Figure 3 As shown, a flow meter 60 and a control valve 70 are provided on the end of the injection pipe 20 away from the detection hole. The control valve 70 is located downstream of the flow meter 60. The flow meter 60 is used to detect the amount of water injected into the injection pipe 20. The flow meter 60 is electrically connected to the processor 30. The processor 30 calculates the depth of the bottom plate damage zone based on the data of the temperature-sensitive optical cable 10 and the flow meter 60. Through the above-mentioned arrangement, the control valve 70 on the end of the injection pipe 20 away from the detection hole can control the on-off of the liquid in the injection pipe 20. The flow meter 60 located upstream of the control valve 70 is used to detect the flow rate injected into the detection hole. In the present application, the flow meter 60 is used to detect the amount of water injected when the liquid level reaches each temperature measuring point of the temperature-sensitive optical cable 10.

[0044] like Figure 2 and Figure 3 As shown, according to another embodiment of the present invention, a detection method for detecting the depth of the bottom plate damage zone is provided. The detection method is applied to the detection device of the above embodiment, and the detection method includes:

[0045] Drilling a test hole on the floor of the goaf 80 of the tunnel;

[0046] Insert one end of the temperature-sensitive optical cable 10 and one end of the injection tube 20 of the detection device into the bottom of the detection hole, continuously inject liquid into the detection hole through the injection tube 20, and obtain the temperature data to be measured along the length direction through the temperature-sensitive optical cable 10;

[0047] Whether the liquid level in the detection hole is in the damage zone is determined according to the temperature data to be measured. If it is in the damage zone, the processor 30 of the detection device calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length between two adjacent temperature measurement points.

[0048] The detection method for detecting the depth of the bottom plate damage zone of the present invention is applied, and the temperature data to be measured along the length direction in the detection hole is obtained through the temperature-sensitive optical cable 10. The processor 30 of the detection device calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length between two adjacent temperature measurement points on the temperature-sensitive optical cable 10. With such a configuration, the detection method is simple, and the operator does not need to perform complex calculations. The processor 30 can accurately analyze the depth of the bottom plate damage zone, which reduces the technical requirements for the operator and does not require complex operations, thereby reducing the difficulty of detection work when detecting the depth of the damage zone. In addition, since the processor 30 can receive the temperature signal from the temperature-sensitive optical cable 10 in real time, and immediately perform analysis and calculation, the temperature data at different positions in the detection hole can be quickly obtained, and analyzed by the processor 30, this rapid analysis and calculation mechanism also improves the detection efficiency.

[0049] In this case, a detection hole is drilled on the bottom plate of the goaf 80 of the tunnel outside the stop mining line 100 to avoid the uncertainty or contingency of the single hole test result. Figure 2 As shown, a group of boreholes are designed on the upper drift 110 and the lower drift 120 outside the stop line 100 of the mining face, and each group includes 3 boreholes. Figure 3 As shown, each borehole is designed with a different inclination angle α, and each group of multiple boreholes is fan-shaped in horizontal projection, and the horizontal projection distance between the final hole positions is 5m to 10m. This arrangement can more comprehensively obtain the data of the bottom plate damage zone, which helps the processor 30 to more accurately calculate the depth of the bottom plate damage zone.

[0050] Specifically, Figure 3As shown, before drilling a detection hole on the bottom plate of the goaf 80 of the tunnel, the depth h1 of the bottom plate mining water-conducting damage zone can be theoretically calculated according to Appendix B2.2 of the "Design Code for Water Control in Coal Mines (GB51070-2014)", and the drilling length is designed according to 1.2 times the calculated and expected depth h1 of the water-conducting damage zone. The relationship between the drilling length L and the drilling inclination angle α is L=1.2h1 / sinα. In this way, the drilling hole is designed according to 1.2 times the calculated and expected depth h1 of the water-conducting damage zone to ensure that a part of the detection hole is in the non-damage zone, that is, a section of the bottom of the detection hole is in the complete rock formation zone, so that the processor 30 can more accurately calculate the depth of the bottom plate damage zone. If the bottom of the detection hole is in the bottom plate damage zone, the flow data of the flow meter 60 at the temperature measuring point of the temperature sensing optical cable 10 remains generally stable, then the processor 30 cannot determine that a certain liquid level is in the bottom plate damage zone, and cannot analyze and calculate the depth of the damage zone. In addition, secondary punching can be avoided, which wastes time and human resources.

[0051] In the embodiment of the present application, the interval length between two adjacent temperature measuring points on the temperature-sensitive optical cable 10 is 0.5 m. In this way, the accuracy of the damage zone depth calculated by the processor 30 is guaranteed to be 0.5 m, thereby improving the calculation accuracy of the damage zone depth.

[0052] Furthermore, the processor 30 calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length between two adjacent temperature measurement points, specifically including:

[0053] Acquire the temperature data to be measured during the water injection period and the flow rate to be measured of the flow meter 60;

[0054] According to the temperature data to be measured, the interval length between two adjacent temperature measuring points and the flow rate to be measured, the water injection volume to be measured per unit height is obtained;

[0055] According to the temperature data to be measured and the flow rate to be measured, it is determined whether the liquid level in the detection hole is in the damage zone. If it is in the damage zone, the flow data of the liquid level is obtained, and the depth of the bottom plate damage zone is calculated according to the flow data and the water injection volume to be measured.

[0056] Specifically, the processor 30 determines whether the liquid level in the detection hole is in the damage zone according to the temperature data to be measured and the flow rate to be measured, which specifically includes: obtaining a length flow curve according to the temperature data to be measured and the flow rate to be measured; wherein, if the increase of the water injection volume per unit length corresponding to a certain length on the length flow curve is greater than or equal to 30%, then the liquid level corresponding to this length is in the damage zone. In this way, the processor 30 records the flow data of each temperature measuring point of multiple detection holes in the length flow curve according to the temperature data of each temperature measuring point measured by the temperature-sensitive optical cable 10 and the flow data measured by the flow meter 60, and then determines that the liquid level corresponding to this length is in the damage zone according to the increase of the water injection volume per unit length corresponding to a certain length on the drawn length flow curve being greater than or equal to 30%.

[0057] Specifically, because there are cracks in the borehole wall of the detection hole in the damaged zone rock formation, the water injection amount will be lost, which greatly increases the water injection amount. If the increase in the water injection amount per unit length is greater than or equal to 30%, it can be judged that the liquid level corresponding to the length is in the damaged zone. However, since there may be cracks on the rock wall of the intact rock formation zone, the water injection amount may be lost even in the intact rock formation zone. There may also be errors in data, operations, etc. If the increase in the water injection amount per unit length is less than 30%, it is judged that the liquid level corresponding to this length is in the damaged zone, which will lead to inaccurate detection of the depth of the damaged zone, which may cause waste of resources or unreasonable allocation of resources.

[0058] In addition, during the water injection process, if the processor 30 can detect the liquid level data of the temperature measuring point on the temperature sensing optical cable 10 at the beginning, but cannot detect the liquid level data of a certain temperature measuring point on the temperature sensing optical cable 10 afterwards, it is because the crack in the damage zone is too large, resulting in the water injection continuing, but the liquid level cannot reach the next temperature measuring point. In this case, the processor 30 compares the water injection amount at the liquid level with the water injection amount measured in the stable layer of the coal seam in the early stage. If the increase is greater than or equal to 30%, it is directly judged that the liquid level corresponding to this length is in the damage zone.

[0059] The tunnel also has a waiting mining area 90. Before judging whether the liquid level in the detection hole is in the damage zone according to the temperature data, the detection method further includes:

[0060] Drilling a control hole on the bottom plate of the area to be mined 90;

[0061] One end of the temperature-sensitive optical cable 10 and one end of the injection tube 20 of the detection device of the control group are passed to the bottom of the control hole, and liquid is continuously injected into the control hole through the injection tube 20, and the control temperature data along the length direction is obtained through the temperature-sensitive optical cable 10; the control temperature data during the water injection period and the control flow rate of the flow meter are obtained; according to the control temperature data, the interval length of two adjacent temperature measuring points and the control flow rate, the control water injection volume per unit height is obtained;

[0062] By comparing the control water injection volume per unit height with the water injection volume to be tested per unit height, it is determined whether the test hole is completely in the damage zone. If the test hole is completely in the damage zone, it is necessary to drill the test hole again; if the test hole is partially in the damage zone, the depth of the damage zone continues to be calculated.

[0063] By setting up a control group, the potential influence of other uncontrolled variables on the detection results can be eliminated, ensuring the accuracy of the detection results. It also provides a comparative benchmark, which helps to reduce selection bias and experimenter bias. In addition, the control water injection volume per unit height is compared with the water injection volume per unit height of a certain section of rock formation. If the two data are basically similar, it can be judged that this section of rock formation is in the stable layer of the coal seam, ensuring that the detection hole is partially in the damage zone.

[0064] According to the comparison between the control water injection volume per unit height and the water injection volume to be tested per unit height, it is judged whether the detection hole is completely in the damage zone, specifically including: if the water injection volume to be tested per unit height is greater than or equal to 1.3 times the control water injection volume per unit height, then the detection hole is judged to be completely in the damage zone. Such a setting can assist in judging whether the detection holes are all in the damage zone. If the water injection volume to be tested per unit height is greater than or equal to 1.3 times the control water injection volume per unit height, then the detection hole is judged to be completely in the damage zone. If the detection hole is completely in the damage zone, it is necessary to return to the design drilling to prevent the phenomenon of inaccurate calculated depth of the damage zone.

[0065] Through the above settings, a control hole is drilled on the bottom plate of the area to be mined 90, and the processor 30 can obtain the control water injection volume per unit height of the control hole, and compare it with the test water injection volume per unit height of the hole to be tested. If the test water injection volume per unit height is greater than or equal to 1.3 times the control water injection volume per unit height, it is judged that the test hole is completely in the damage zone, and it is necessary to return to the designed drilling hole, which helps the processor 30 to calculate the depth of the bottom plate damage zone more accurately.

[0066] In this way, the processor 30 obtains the temperature data to be measured along the length direction through the temperature-sensing optical cable 10, and first determines whether the liquid level in the detection hole is in the damage zone based on the measured temperature data. If the temperature data of the temperature-sensing optical cable at the temperature measuring point along the length direction has obvious changes, it means that the liquid level has reached the temperature measuring point. At this time, it is also necessary to determine whether the liquid level in the detection hole is in the damage zone based on the unit height of water injection required for the liquid level to reach the liquid level. If the unit height of water injection consumed is significantly increased, it can be determined that the liquid level is in the damage zone. The processor 30 can quickly calculate the depth of the bottom plate damage zone, which greatly reduces the difficulty of detecting the depth of the bottom plate damage zone and greatly improves the detection efficiency.

[0067] The detection device and method for detecting the depth of the bottom plate damage zone provided by the present application have the following advantages:

[0068] 1. The detection device and method for detecting the depth of the floor damage zone proposed in the present invention utilize the temperature sensitivity of the temperature-sensitive optical cable and combine it with the precise analysis of the processor to achieve real-time monitoring and recording of the temperature at different positions in the borehole, thereby indirectly probing the depth of the floor damage caused by mining. Compared with traditional methods, this method can more accurately reflect the development of cracks in the mining rock formation and improve the reliability of the detection results.

[0069] 2. The detection device and method for detecting the depth of the bottom plate damage zone of the present invention adopt high-quality materials and structural design, and have high durability and reusability. The optical cable and other key components can be reused, which reduces the detection cost and improves the economic benefit.

[0070] 3. The temperature sensing optical cable has excellent transmission performance, can realize long-distance temperature signal transmission, and is not affected by electromagnetic interference. This enables this technology to work stably in the complex and high electromagnetic interference coal mine environment, improving the reliability and stability of detection.

[0071] 4. The present invention utilizes the temperature testing capability of the relatively mature temperature-sensing optical cable. With the help of the processor, the temperature signal from the temperature-sensing optical cable can be received in real time, and the temperature data at different positions in the borehole can be analyzed and calculated immediately to quickly obtain the temperature data, which can be displayed through the processor. This instant feedback mechanism enables the operator to quickly grasp the dynamic changes of the water level in the test hole, reduces the technical requirements for the operator, and has general applicability.

[0072] 5. The detection device and method for detecting the depth of the bottom plate damage zone of the present invention have shown great advantages in detection efficiency, which is specifically reflected in the fact that its single detection range is not limited. The device can detect the entire hole section each time. Compared with the traditional double-end water pressure leak detection method, this data has achieved a qualitative leap, greatly improved detection efficiency, and greatly reduced the number and time of detection.

[0073] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0074] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0075] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0076] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0077] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A detection device for detecting the depth of the bottom plate damage zone, characterized in that: The detection device comprises: A temperature-sensitive optical cable (10) is used to measure the temperature in the detection hole, wherein the temperature-sensitive optical cable (10) has a plurality of temperature measurement points distributed at equal intervals along the length direction; A liquid injection pipe (20) is arranged side by side with the temperature-sensitive optical cable (10), and the liquid injection pipe (20) is used to inject liquid into the detection hole; A processor (30) is electrically connected to the temperature-sensitive optical cable (10), and the processor (30) calculates the depth of the bottom plate damage zone according to detection data of the temperature-sensitive optical cable (10).

2. The detection device according to claim 1, characterized in that: The detection device also includes: A protective tube (40) is sleeved on the outside of the temperature-sensitive optical cable (10), and a connecting hole is provided on the protective tube (40), wherein the connecting hole is used to communicate with the detection hole so that the liquid in the injection tube (20) can flow into the protective tube (40).

3. The detection device according to claim 2, characterized in that: The protection tube (40) is fixedly connected to the liquid injection tube (20) in parallel, and the detection device further comprises: A guide head (50) is mounted on one end of the protection tube (40) located at the detection hole and one end of the injection tube (20) located at the detection hole, and the cross-sectional size of the guide head (50) gradually decreases from the direction toward the bottom of the detection hole.

4. The detection device according to claim 2, characterized in that: The protection tube (40) has a plurality of communicating holes, and the plurality of communicating holes are evenly distributed on the side wall of the protection tube (40); the injection tube (20) has a plurality of injection holes, and the plurality of injection holes are evenly distributed on the side wall of one end of the injection tube (20) located in the detection hole.

5. The detection device according to claim 1, characterized in that: A flow meter (60) and a control valve (70) are provided on one end of the injection pipe (20) away from the detection hole. The control valve (70) is located downstream of the flow meter (60). The flow meter (60) is used to detect the amount of water injected into the injection pipe (20). The flow meter (60) is electrically connected to the processor (30). The processor (30) calculates the depth of the bottom plate damage zone based on data from the temperature-sensitive optical cable (10) and the flow meter (60).

6. A detection method for detecting the depth of the bottom plate damage zone, characterized in that: The detection method is applied to the detection device according to any one of claims 1 to 5, and the detection method comprises: Drilling a detection hole on the floor of the goaf (80) of the tunnel; Inserting one end of the temperature-sensitive optical cable (10) and one end of the liquid injection tube (20) of the detection device into the bottom of the detection hole, continuously injecting liquid into the detection hole through the liquid injection tube (20), and obtaining temperature data to be measured along the length direction through the temperature-sensitive optical cable (10); It is determined whether the liquid level in the detection hole is in the damage zone according to the temperature data to be measured. If it is in the damage zone, the processor (30) of the detection device calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length between two adjacent temperature measurement points.

7. The detection method according to claim 6, characterized in that: The detection device is the detection device according to claim 5, and the processor (30) calculates the depth of the bottom plate damage zone according to the temperature data to be measured and the interval length between two adjacent temperature measurement points, specifically comprising: Acquiring the temperature data to be measured and the flow rate to be measured of the flow meter (60) during the water injection period; According to the temperature data to be measured, the interval length between two adjacent temperature measuring points and the flow rate to be measured, obtaining the water injection volume to be measured per unit height; According to the temperature data to be measured and the flow rate to be measured, it is determined whether the liquid level in the detection hole is in the damage zone. If it is in the damage zone, the flow data of the liquid level is obtained, and the depth of the bottom plate damage zone is calculated according to the flow data and the water injection volume to be measured.

8. The detection method according to claim 7, characterized in that: Judging whether the liquid level in the detection hole is in a damage zone according to the temperature data to be measured and the flow rate to be measured specifically includes: Obtaining a length-flow curve according to the temperature data to be measured and the flow rate to be measured; If the increase in the water injection volume per unit length corresponding to a certain length on the length-flow curve is greater than or equal to 30%, the liquid level corresponding to this length is in the damage zone.

9. The detection method according to claim 7, characterized in that: The tunnel also has a waiting mining area (90). Before judging whether the liquid level in the detection hole is in a damage zone according to the temperature data, the detection method further comprises: Drilling a control hole on the bottom plate of the area to be mined (90); Inserting one end of the temperature-sensitive optical cable (10) and one end of the liquid injection tube (20) of the detection device of the control group into the bottom of the control well, continuously injecting liquid into the control well through the liquid injection tube (20), and obtaining control temperature data along the length direction through the temperature-sensitive optical cable (10); Obtain reference temperature data during water injection and reference flow rate from flow meter; According to the control temperature data, the interval length between two adjacent temperature measuring points and the control flow rate, a control water injection volume per unit height is obtained; Based on the comparison between the control water injection volume per unit height and the water injection volume to be tested per unit height, it is determined whether the detection hole is completely in the damage zone. If the detection hole is completely in the damage zone, it is necessary to re-drill the detection hole; if the detection hole is partially in the damage zone, the depth of the damage zone continues to be calculated.

10. The detection method according to claim 9, characterized in that: According to the comparison between the control water injection volume per unit height and the water injection volume to be tested per unit height, judging whether the detection hole is completely in the damage zone specifically includes: If the water injection volume to be tested per unit height is greater than or equal to 1.3 times the control water injection volume per unit height, it is determined that the detection hole is completely in the damage zone.

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