Tailings dam leakage monitoring positioning and leakage-preventing membrane and construction method thereof

Abstract

The application discloses a tailing dam leakage monitoring positioning and leakage repairing anti-seepage film and a construction method thereof, wherein the tailing dam leakage monitoring positioning and leakage repairing anti-seepage film comprises: an anti-seepage composite film which is composed of multiple layers of anti-seepage films combined together; a dense quasi-distributed armored optical fiber sensing cable which is arranged in the anti-seepage composite film, can monitor stress and temperature changes in the anti-seepage composite film in real time, can judge whether leakage occurs in the anti-seepage composite film according to the stress and temperature changes, and can position the leakage position when the leakage occurs; and a leakage repairing system which is arranged in the anti-seepage composite film and can repair the leakage position when the leakage occurs. When the construction is performed, the site is leveled, the blind drainage ditch is excavated and laid, the sand cushion layer and the cohesive soil cushion layer are laid, then the anti-seepage composite film in which the dense quasi-distributed armored optical fiber sensing cable and the leakage repairing system are combined is laid on the cohesive soil cushion layer, finally, the lead wire is laid and connected to the optical fiber demodulator. The tailing dam and the anti-seepage film leakage monitoring, the leakage position positioning and the leakage repairing are integrated.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering and relates to a tailings dam leakage monitoring, location, and repair membrane and its construction method. Background Technology

[0002] Tailings ponds are sites for storing tailings or industrial waste. Tailings dams, as a crucial component of tailings ponds, play a direct and decisive role in the safety of the pond. During the accumulation process, tailings water can seep into the dam, causing seepage damage and even dam failure. Once a tailings dam fails, the water and tailings within the pond will not only cause enormous damage to the lives and property of people downstream, but also result in severe environmental pollution.

[0003] Currently, tailings dam seepage prevention measures mainly consist of rockfill dams, geomembranes, or a combination of both. These measures can address the leakage and damage caused by the large porosity of rockfill dams. However, the geomembranes are relatively thin, and as the tailings dam accumulates, its own weight pressure increases. The thin geomembrane is prone to damage under the complex terrain and significant weight pressure of the tailings dam, leading to its failure. To address the seepage damage in tailings dams, engineers have developed many tailings seepage sealing structures. However, these structures and devices can only be manually sealed after significant seepage damage has occurred on the dam slope and is discovered during manual inspections. Furthermore, they can only seal the surface seepage on the dam slope. Tailings dam seepage damage often occurs deep within the dam, resulting in a much larger internal seepage area than the surface. This means that existing sealing structures and devices cannot seal the dam immediately upon leakage, nor can they repair the dam body. Meanwhile, the detection of tailings dam leakage is generally carried out through manual inspection and hydrological tracing tests. However, these methods are time-consuming and labor-intensive, cannot be carried out in severe weather, and have low safety assurance.

[0004] With the continuous development of fiber optic sensing technology in geotechnical engineering, distributed fiber optic temperature sensing technology has attracted attention in tailings dam leakage monitoring. However, distributed fiber optic temperature sensing technology has high demodulation costs and low accuracy, so it has not been widely applied to tailings dam leakage monitoring to date. Summary of the Invention

[0005] The purpose of this invention is to provide a tailings dam leakage monitoring, location, and repair membrane to solve the problems of tailings dam membranes easily failing due to tailings accumulation, existing tailings dam leakage detection methods being time-consuming and labor-intensive, unable to be carried out in severe weather, and having low safety assurance, existing sealing structures and devices being unable to promptly seal leaks inside tailings dams, and distributed fiber optic temperature measurement technology being unable to be widely applied to tailings dam leakage detection and monitoring due to high adjustment costs and low accuracy.

[0006] Another objective of this invention is to provide a method for monitoring, locating, and repairing leak-proof membranes in tailings dams.

[0007] The technical solution adopted in this embodiment of the invention is: a tailings dam leakage monitoring, location, and repair membrane, comprising:

[0008] A geomembrane is composed of multiple layers of geomembranes joined together.

[0009] The dense quasi-distributed armored fiber optic sensing cable is installed inside the geomembrane to monitor stress and temperature changes within the geomembrane in real time. Based on these stress and temperature changes, it determines whether leakage has occurred and locates the leakage point when leakage does occur.

[0010] The leak repair system is installed inside the geomembrane to repair leaks when they occur.

[0011] Furthermore, the impermeable composite membrane is internally fitted with a metal mesh, and the densely distributed armored optical fiber sensing cable and the leak repair system are fixed to the metal mesh.

[0012] Furthermore, the thickness of each layer of the geomembrane is 0.5 to 1 mm;

[0013] The impermeable composite membrane is composed of four layers of impermeable membranes joined together, from top to bottom: the first impermeable membrane, the second impermeable membrane, the third impermeable membrane, and the fourth impermeable membrane. A metal mesh is embedded between the second and third impermeable membranes.

[0014] Furthermore, the dense quasi-distributed armored fiber optic sensing cable is laid on top of the metal mesh, and the leak repair system is laid at the bottom of the metal mesh.

[0015] Furthermore, the first geomembrane is a polypropylene membrane, the second geomembrane is a polyvinyl chloride membrane, the third geomembrane is a high-density polyethylene membrane, and the fourth geomembrane is a polyethylene film.

[0016] Furthermore, the aforementioned dense quasi-distributed armored fiber optic sensing cable is a grid structure formed by armored fiber optic sensing cables laid along a metal mesh, which divides the tailings dam into several grids for leakage detection and monitoring.

[0017] The armored fiber optic sensing cable includes, from the inside out, a sensing fiber, a waterproof layer, an inner protective layer, and an outer protective layer. The sensing fiber is engraved with a weak reflection fiber Bragg grating. The reflectivity of a single weak reflection fiber Bragg grating is less than 0.1%, and the spacing between two adjacent weak reflection fiber Bragg gratings is less than 50 cm and the reflectivity is less than 0.5%.

[0018] Furthermore, the leak repair system includes a central processing unit and leak repair pipes. The central processing unit is located in the control room or control cabinet of the tailings dam. The leak repair pipes are laid out along the metal mesh to form a grid structure, dividing the tailings dam into several grids for leak repair. Dense quasi-distributed armored fiber optic sensing cables collect the tailings dam leakage situation and leakage location and feed them back to the central processing unit. The central processing unit controls the leak repair pipes at the leakage location to repair the leak through data lines.

[0019] Furthermore, the leak repair pipe includes:

[0020] The heating wire is positioned in the middle of the heat fusion tube.

[0021] Leak sealing fluid is used to fill the heat fusion tube;

[0022] in:

[0023] Each section of the heat fusion tube is equipped with a solenoid valve;

[0024] Each solenoid valve is connected to the circuit that connects the heating wire it controls to the heating power supply. The solenoid valves are connected in parallel and connected to the central processing unit via a data cable.

[0025] The heat fusion tube is wrapped with a signal shielding tube, and the heat fusion tube and the signal shielding tube are provided with a leak-proof hole for the leak-proof liquid to flow out after melting.

[0026] Another technical solution adopted in this embodiment of the invention is: a construction method for monitoring, locating, and repairing seepage-proof membranes for tailings dam leakage, comprising the following steps:

[0027] Step S1. Site leveling: Level the valley site where the tailings dam is located and compact the exposed gravel;

[0028] Step S2. Excavation and laying of drainage blind ditch: Determine the location of the drainage blind ditch, excavate the blind ditch, lay geotextile in the blind ditch, fill it with gravel, and level the site again after laying.

[0029] Step S3. Laying sand and clay cushion layer: Use medium-coarse sand to level the site, then sprinkle water and compact it with a road roller. After the sand cushion layer is laid, lay the clay cushion layer on top of the sand cushion layer.

[0030] Step S4. Process the impermeable composite membrane and install the dense quasi-distributed armored fiber optic sensing cable and leak repair system;

[0031] Step S5. Construct a waterproof composite membrane with dense quasi-distributed armored fiber optic sensing cables and a leak repair system;

[0032] Step S6. Lay the lead wire and connect it to the fiber optic demodulator: Connect the dense quasi-distributed armored fiber optic sensing cable to the fiber optic demodulator through the lead wire. The monitoring data is sent to the PC through the fiber optic demodulator. At the same time, connect the data line of the leak repair system to the central processing unit.

[0033] Furthermore, the specific implementation process of step S4 is as follows:

[0034] The first geomembrane is combined with the second geomembrane, the assembled dense quasi-distributed armored fiber optic sensing cable and leak repair system are fixed on the metal mesh, the metal mesh is then fixed between the second and third geomembrane, and a fourth geomembrane is combined under the third geomembrane.

[0035] The specific implementation process of step S5 is as follows:

[0036] The processed impermeable composite membrane, which incorporates dense quasi-distributed armored optical fiber sensing cables and a leak repair system, is laid on the cohesive soil cushion layer and fixed in place.

[0037] The beneficial effects of the embodiments of the present invention are:

[0038] 1. A tailings dam leakage monitoring, location, and repair geomembrane is proposed. This geomembrane structure integrates automatic monitoring of tailings dam and geomembrane leakage, automatic location of leakage, and repair functions. While preventing leakage of tailings and tailings water in the tailings dam, it can monitor the temperature and pressure changes of the bottom geomembrane of the tailings dam online through dense quasi-distributed armored fiber optic sensing cables, reflecting the leakage location and situation of the tailings dam in real time, accurately locating the leakage location. At the same time, it can also repair the leakage by expanding upon contact with water using a built-in water-absorbing expansion agent. It can be pre-buried at the bottom of the tailings dam, requiring no manual intervention during detection and monitoring, and is not affected by severe weather. It has a fast response speed and solves the problems that existing sealing structures and devices cannot seal the leakage inside the tailings dam, as well as the problems that existing tailings dam leakage detection methods are time-consuming and labor-intensive, cannot be carried out in severe weather, and have low safety assurance.

[0039] 2. A seepage-proof composite membrane is proposed, which combines a metal mesh, a leak repair system, and a dense quasi-distributed armored fiber optic sensing cable to achieve seepage monitoring, seepage location, and leak repair, while effectively improving the strength of the seepage-proof composite membrane. This avoids the composite seepage-proof membrane from undergoing large deformation and failure under upper loads, and solves the problem that the existing seepage-proof membranes of tailings dams are prone to failure as tailings accumulate.

[0040] 3. The dense quasi-distributed armored fiber optic sensing cable uses WFBG, which has the advantages of large grating capacity, high precision and low demodulation cost. The dense quasi-distributed armored fiber optic sensing cable is arranged in a three-dimensional mesh at the bottom of the dam body, which can grid the dam body and accurately locate the leakage location. This solves the problem that distributed fiber optic temperature measurement technology cannot be widely applied to tailings dam leakage detection and monitoring due to high demodulation cost and low precision. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a three-dimensional structural schematic diagram of the impermeable composite membrane according to an embodiment of the present invention.

[0043] Figure 2 This is a schematic diagram of the vertical cross-sectional structure of the impermeable composite membrane according to an embodiment of the present invention.

[0044] Figure 3 This is a schematic diagram showing the positional relationship between the metal mesh, the dense quasi-distributed armored optical fiber sensing cable, and the leak repair system in an embodiment of the present invention.

[0045] Figure 4 This is a schematic diagram of the structure of the armored optical fiber sensing cable according to an embodiment of the present invention.

[0046] Figure 5 This is a schematic diagram of the leak repair system according to an embodiment of the present invention.

[0047] Figure 6 This is the spectrum of a weakly reflective fiber Bragg grating (WFBG).

[0048] In the diagram, 1. geomembrane, 2. dense quasi-distributed armored fiber optic sensing cable, 3. first geomembrane layer, 4. second geomembrane layer, 5. metal mesh, 6. third geomembrane layer, 7. leak repair system, 8. fourth geomembrane layer, 9. clay cushion layer, 10. weakly reflective fiber Bragg grating, 11. waterproof layer, 12. inner protective layer, 13. outer protective layer, 14. heating wire, 15. leak repair fluid, 16. heat fusion tube, 17. signal shielding tube. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Example 1

[0051] This embodiment proposes a tailings dam leakage monitoring, location, and repair membrane, such as... Figures 1-2 As shown, it includes:

[0052] Geomembrane 1, which is composed of multiple layers of geomembrane joined together.

[0053] The dense quasi-distributed armored fiber optic sensing cable 2 is installed inside the impermeable composite membrane 1 to monitor the stress and temperature changes inside the impermeable composite membrane 1 in real time. Based on the stress and temperature changes inside the impermeable composite membrane 1, it can determine whether leakage has occurred and locate the leakage location when leakage occurs.

[0054] Leak repair system 7 is installed inside the impermeable composite membrane 1 to repair leaks when they occur.

[0055] In some embodiments, a metal mesh 5 is disposed inside the impermeable composite membrane 1, and a densely quasi-distributed armored fiber optic sensing cable 2 and a leak repair system 7 are fixed on the metal mesh 5. Figure 3 As shown, while fixing the dense quasi-distributed armored fiber optic sensing cable 2 and the leak repair system 7, it also improves the strength of the seepage-proof composite membrane 1 to ensure that the seepage-proof composite membrane 1 does not break down as the dam slope deforms during the tailings dam accumulation process.

[0056] In some embodiments, the geomembrane 1 is composed of four geomembranes joined together, from top to bottom: a first geomembrane 3, a second geomembrane 4, a third geomembrane 6, and a fourth geomembrane 8. A metal mesh 5 is embedded between the second geomembrane 4 and the third geomembrane 6. The mesh size of the metal mesh 5 is less than 50cm × 50cm, preferably 10cm × 10cm, in order to more accurately locate the leakage point.

[0057] In some embodiments, the dense quasi-distributed armored fiber optic sensing cable 2 is laid on top of the metal mesh 5, and the leak repair system 7 is laid on the bottom of the metal mesh 5.

[0058] In some embodiments, the first geomembrane 3 is a polypropylene (PP) membrane, the second geomembrane 4 is a polyvinyl chloride (PVC) membrane, the third geomembrane 6 is a high-density polyethylene (HDPE) membrane, and the fourth geomembrane 8 is a polyethylene film, thereby achieving environmentally friendly unidirectional seepage prevention.

[0059] In some embodiments, the thickness of each layer of the geomembrane 1 is 0.5 to 1 mm, which ensures the sensing accuracy of the dense quasi-distributed armored fiber optic sensing cable 2, while combining with the metal mesh 5, the dense quasi-distributed armored fiber optic sensing cable 2 and the leak repair system 7 to improve the strength of the geomembrane 1.

[0060] In some embodiments, two adjacent geomembranes of the geomembrane 1 are bonded together.

[0061] In some embodiments, the dense quasi-distributed armored fiber optic sensing cable 2 is a grid structure formed by armored fiber optic sensing cables laid along the metal mesh 5, dividing the tailings dam into several grids for leakage detection and monitoring. For example... Figure 4 As shown, the armored fiber optic sensing cable includes, from the inside out, a sensing fiber, a waterproof layer 11, an inner protective layer 12, and an outer protective layer 13. Weakly reflective fiber Bragg gratings (WFBGs) 10 are inscribed on the sensing fiber. The reflectivity of a single WFBG 10 is less than 0.1%, and the spacing between two adjacent WFBGs 10 is less than 50 cm with a reflectivity less than 0.5%. WFBGs have the advantages of large capacity, high precision, and low demodulation cost. Arranged in a three-dimensional mesh at the bottom of the dam, they can grid the dam body and accurately locate the seepage point. When the external temperature changes or stress acts on the WFBG at a certain grid point of the densely distributed armored fiber optic sensing cable 2, it will cause a change in its period, resulting in a drift in the center wavelength of the measured weakly reflective fiber Bragg grating 10. Figure 6 As shown, based on this principle, the demodulator can be used to detect and monitor changes in the external environment such as temperature and pressure in real time. By comparing the temperature and pressure differences detected by all armored fiber optic sensing cables, the leakage location and leakage situation of the anti-seepage composite membrane 1 can be reflected in real time, thus realizing the location of the leakage point.

[0062] In some embodiments, the leak repair system 7 includes a central processing unit (CPU) and leak repair pipes. The CPU is located in the control room / control cabinet of the tailings dam, and the leak repair pipes are arranged in a grid structure along the metal mesh 5. Figure 3 As shown, the tailings dam is divided into several grids for leak repair. The dense quasi-distributed armored fiber optic sensing cable 2 collects the tailings dam leakage situation and leakage location and feeds it back to the central processing unit. The central processing unit controls the leak repair pipe at the leakage location to repair the leak through the data line.

[0063] In some embodiments, such as Figure 5As shown, the leak repair pipe includes:

[0064] Heating wire 14 is disposed in the middle of heat fusion tube 16;

[0065] Solid sealant 15 is filled into heat fusion tube 16;

[0066] in:

[0067] Each section of the heat-melting tube 16 is fixed with a solenoid valve. Each solenoid valve is connected to the line connecting the heating wire 14 it controls to the heating power supply. The solenoid valves are connected in parallel and connected to the central processing unit via a data cable.

[0068] The heat fusion tube 16 is wrapped with a signal shielding tube 17. Both the heat fusion tube 16 and the signal shielding tube 17 have leak-proof holes for the leak-proof liquid 15 to flow out after melting.

[0069] The dense quasi-distributed armored fiber optic sensing cable 2 collects the tailings dam leakage information and location and feeds it back to the central processing unit. The central processing unit transmits the heating signal to the solenoid valve at the leakage location via the data line, controls the solenoid valve to open, and heats the heating wire 14 at the leakage location. After the heating wire 14 is heated, it melts the sealing liquid 15. The sealing liquid 15 flows out from the sealing hole and expands when it comes into contact with water, thereby sealing the leakage location.

[0070] In some embodiments, the sealant is a water-absorbing and swelling agent.

[0071] In some embodiments, a cohesive soil cushion layer 9 is laid between the bottom of the impermeable composite membrane 1 and the tailings dam, and the three-dimensional thickness of the cohesive soil cushion layer 9 is 5-10 cm.

[0072] Example 2

[0073] This embodiment proposes a method for monitoring, locating, and repairing seepage in tailings dams using a waterproof membrane, comprising the following steps:

[0074] Step S1. Site leveling: Level the valley site where the tailings dam is located and compact the exposed gravel;

[0075] Step S2. Excavation and laying of drainage blind ditch: Determine the location of the drainage blind ditch, excavate the blind ditch, lay geotextile in the blind ditch, fill it with gravel, and level the site again after laying.

[0076] Step S3. Laying sand cushion layer and cohesive soil cushion layer: Use medium and coarse sand to level the site, sprinkle water after leveling and compact it with a road roller. After the sand cushion layer is laid, lay cohesive soil cushion layer 9 on the sand cushion layer. The thickness of cohesive soil cushion layer 9 is not less than 5cm.

[0077] Step S4. Processing the geomembrane 1 and installing the dense quasi-distributed armored fiber optic sensing cable 2 and the leak repair system 7: Composite the polypropylene (PP) membrane, i.e. the first geomembrane 3, with the polyvinyl chloride (PVC) membrane, i.e. the second geomembrane 4; fix the assembled dense quasi-distributed armored fiber optic sensing cable 2 and leak repair system 7 onto the metal mesh 5; then fix the metal mesh 5 between the polyvinyl chloride (PVC) membrane, i.e. the second geomembrane 4, and the HDPE membrane, i.e. the third geomembrane 6; composite the polyethylene film, i.e. the fourth geomembrane 8, under the HDPE membrane;

[0078] Step S5. Construction of the seepage-proof composite membrane 1 with dense quasi-distributed armored fiber optic sensing cable 2 and leak repair system 7: The processed leak repair and seepage-proof membrane is laid on the cohesive soil cushion layer 9 and fixed.

[0079] Step S6. Lay the lead wire and connect it to the fiber optic demodulator: Connect the dense quasi-distributed armored fiber optic sensing cable 2 to the fiber optic demodulator through the lead wire. The monitoring data is sent to the PC through the fiber optic demodulator. At the same time, connect the data line of the leak repair system 7 to the central processing unit.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A tailings dam leakage monitoring, location, and repair membrane, characterized in that, include: The geomembrane (1) is composed of multiple geomembranes joined together. Dense quasi-distributed armored fiber optic sensing cable (2) is installed inside the impermeable composite membrane (1) to monitor the stress and temperature changes inside the impermeable composite membrane (1) in real time, and to determine whether leakage has occurred based on the stress and temperature changes inside the impermeable composite membrane (1), and to locate the leakage location when leakage occurs. The leak repair system (7) is installed inside the impermeable composite membrane (1) to repair the leak when leakage occurs; The impermeable composite membrane (1) is provided with a metal mesh (5) inside, and a dense quasi-distributed armored optical fiber sensing cable (2) and a leak repair system (7) are fixed on the metal mesh (5); The leak repair system (7) includes a central processing unit and a leak repair pipe. The central processing unit is located in the control room or control cabinet of the tailings dam. The leak repair pipe is laid out along the metal mesh (5) in a grid structure to divide the tailings dam into several grids for leak repair. The dense quasi-distributed armored fiber optic sensing cable (2) collects the tailings dam leakage situation and leakage location and feeds it back to the central processing unit. The central processing unit controls the leak repair pipe at the leakage location to repair the leak through the data line. The leak repair pipe includes: Heating wire (14) is placed in the middle of heat fusion tube (16); Leakage sealant (15) is filled into the heat fusion tube (16); in: Each section of the heat fusion tube (16) is equipped with a solenoid valve; Each solenoid valve is connected to the line connecting the heating wire (14) it controls to the heating power supply. The solenoid valves are set in parallel and connected to the central processing unit via a data cable. The heat fusion tube (16) is wrapped with a signal shielding tube (17) on the outside. The heat fusion tube (16) and the signal shielding tube (17) are provided with a leak-proof hole for the leak-proof liquid (15) to flow out after melting.

2. The tailings dam leakage monitoring, location, and repair membrane according to claim 1, characterized in that, The thickness of each layer of the geomembrane (1) is 0.5~1mm; The impermeable composite membrane (1) is composed of four layers of impermeable membranes joined together, from top to bottom as the first layer of impermeable membrane (3), the second layer of impermeable membrane (4), the third layer of impermeable membrane (6) and the fourth layer of impermeable membrane (8), with a metal mesh (5) embedded between the second layer of impermeable membrane (4) and the third layer of impermeable membrane (6).

3. The tailings dam leakage monitoring, location, and repair membrane according to claim 2, characterized in that, The dense quasi-distributed armored fiber optic sensing cable (2) is laid on top of the metal mesh (5), and the leak repair system (7) is laid on the bottom of the metal mesh (5).

4. The tailings dam leakage monitoring, location, and repair membrane according to claim 2, characterized in that, The first geomembrane (3) is a polypropylene membrane, the second geomembrane (4) is a polyvinyl chloride membrane, the third geomembrane (6) is a high-density polyethylene membrane, and the fourth geomembrane (8) is a polyethylene film.

5. The tailings dam leakage monitoring, location, and repair membrane according to claim 4, characterized in that, The dense quasi-distributed armored fiber optic sensing cable (2) is a grid structure formed by the armored fiber optic sensing cable along the metal mesh (5), which divides the tailings dam into several grids for leakage detection and monitoring. The armored fiber optic sensing cable includes a sensing fiber, a waterproof layer (11), an inner protective layer (12), and an outer protective layer (13) arranged sequentially from the inside to the outside. The sensing fiber is engraved with a weak reflection fiber Bragg grating (10). The reflectivity of a single weak reflection fiber Bragg grating (10) is less than 0.1%, and the interval between two adjacent weak reflection fiber Bragg gratings (10) is less than 50 cm.

6. A construction method for monitoring, locating, and repairing seepage-proof membranes for tailings dam leakage as described in any one of claims 2 to 5, characterized in that, Includes the following steps: Step S1. Site leveling: Level the valley site where the tailings dam is located and compact the exposed gravel; Step S2. Excavation and laying of drainage blind ditch: Determine the location of the drainage blind ditch, excavate the blind ditch, lay geotextile in the blind ditch, fill it with gravel, and level the site again after laying. Step S3. Laying sand cushion and cohesive soil cushion: Use medium-coarse sand to level the site, sprinkle water after leveling and compact it with a road roller. After the sand cushion is laid, lay the cohesive soil cushion on the sand cushion (9). Step S4. Process the impermeable composite membrane (1) and install the dense quasi-distributed armored fiber optic sensing cable (2) and the leak repair system (7). Step S5. Construct a seepage-proof composite membrane (1) with a dense quasi-distributed armored optical fiber sensing cable (2) and a leak repair system (7). Step S6. Lay the lead wire and connect it to the fiber optic demodulator: Connect the dense quasi-distributed armored fiber optic sensing cable (2) to the fiber optic demodulator through the lead wire. The monitoring data is sent to the PC through the fiber optic demodulator. At the same time, connect the data line of the leak repair system (7) to the central processing unit.

7. The construction method for monitoring, locating, and repairing seepage prevention membranes in tailings dams according to claim 6, characterized in that, The specific implementation process of step S4 is as follows: The first geomembrane (3) is combined with the second geomembrane (4), the assembled dense quasi-distributed armored fiber optic sensing cable (2) and the leak repair system (7) are fixed on the metal mesh (5), the metal mesh (5) is fixed between the second geomembrane (4) and the third geomembrane (6), and the fourth geomembrane (8) is combined under the third geomembrane (6). The specific implementation process of step S5 is as follows: The processed impermeable composite membrane (1), which is combined with dense quasi-distributed armored optical fiber sensing cable (2) and leak repair system (7), is laid on the cohesive soil cushion layer (9) and fixed.

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