A process and device for detecting leakage of a mine chamber sealing layer

Abstract

This invention relates to the field of leakage detection technology, specifically to a process and apparatus for detecting leaks in the sealing layer of an artificial chamber. The process includes creating a sealed space through a gap; continuously evacuating the gap; and using an acoustic imaging device to perform full-area leakage detection on the inner side of the sealing layer while maintaining a preset negative pressure value within the gap. If a leak point exists in the sealing layer, the negative pressure within the gap on the outer side of the sealing layer causes airflow to flow from the inner side of the sealing layer to the outer side of the gap, generating characteristic sound waves for detection and identification by the acoustic imaging device, and visualizing the results as a cloud map. In this invention, by sealing the inherent through-type gap of the artificial chamber to create a sealed space, and then evacuating to construct a full-area negative pressure, full-area leakage detection of the sealing layer is achieved in conjunction with the acoustic imaging device. The leak point is accurately located through visualization of the characteristic sound wave cloud map, thus overcoming the limitations of traditional local detection, improving vacuuming efficiency, and simplifying operation.

Description

Technical Field

[0001] This invention relates to the field of leak detection technology, specifically to a process and device for leak detection of the sealing layer of artificial chambers. It is particularly applicable to acceptance testing and periodic maintenance testing during the construction of the main structure and sealing layer of artificial chambers in scenarios such as deep burial of nuclear waste, underground gas storage facilities, national defense engineering shelters, underground energy storage power stations, and storage of highly hazardous chemicals. Background Technology

[0002] As an underground enclosed space structure, the operational safety of an artificial cavern depends heavily on the sealing layer laid on its inner wall. This sealing layer must simultaneously achieve a two-way barrier function: on the one hand, it must prevent external groundwater, air, and corrosive media from seeping into the cavern interior; on the other hand, it must prevent hazardous substances such as radionuclides, combustible gases, and toxic chemicals from leaking out of the cavern interior.

[0003] Figure 1 The diagram illustrates an artificial chamber consisting of a lining 1 and a sealing layer 2. Specifically, after construction, the sealing layer 2 forms an integral structure, and the sealing layer 2 is fixed to the lining 1 using a dot-matrix fixing method. That is, after fixing, the gap 3 between the back side of the sealing layer 2 (i.e., the side that adheres to the lining 1, with its front side facing the interior of the chamber) and the lining 1 is completely open (resulting in a through gap). Furthermore, drainage pipes are installed around the artificial chamber, and these drainage pipes do not penetrate the sealing layer 2.

[0004] The basic structure of the artificial tunnel described in this application has been disclosed above. Regarding the leakage detection of this sealing layer, there are already relevant solutions in the prior art. For example, the utility model patent with publication number CN220649943U discloses a test device for the waterproof performance of railway tunnels. Its core detection principle is negative pressure combined with soap water tracer method. The specific operation process is as follows: start the water pump to pressurize the soap water in the water tank, and spray it from the spray gun to the wall to be tested through the hose. Then, press the transparent test cover with the sealing ring against the wall to form a closed space. Start the vacuum pump and open the solenoid valve to extract the air in the test cover to form a negative pressure. After the pressure gauge reaches the set threshold, close the vacuum pump and the solenoid valve. By observing the pressure relief of the pressure gauge and whether the soap water in the test cover produces bubbles, it is determined whether there are leakage defects in the tunnel wall.

[0005] It is evident that leak detection of the sealing layer in artificial chambers still largely relies on manual operation. This is because artificial chambers are relatively large, and there is a lack of directly adaptable, comprehensive testing equipment. This type of testing requirement differs significantly from the sealing testing of small, regularly sealed components such as glass bottles and sealed containers, which only require sealing a single opening to achieve comprehensive sealing of the entire cavity. Furthermore, existing testing equipment cannot perform comprehensive testing of large cavities. Therefore, operators must carry simple, portable testing tools and flexibly adjust the testing position and method according to the actual spatial structure of the chamber and the key areas to be tested, adapting to the complex spatial structure and testing requirements within the chamber.

[0006] However, in the current technology, there is no relevant solution to create full-area detection conditions by utilizing the basic structure of the artificial chamber itself, which means that the existing detection solutions can only achieve local small-scale leakage detection; and apart from a few detection methods that are complicated to operate and have high costs, which can achieve precise location of the leak point, most simple portable tools can only qualitatively determine whether there is a leak in the sealing layer, and cannot achieve the location of the leak point. Summary of the Invention

[0007] In view of this, in order to solve at least one technical problem in related technologies and other aspects, this disclosure proposes a process and device for detecting leakage in the sealing layer of an artificial chamber.

[0008] Firstly, a leakage detection process for the sealing layer of an artificial chamber is provided, including: The through gap on the outside of the sealing layer is sealed to form a closed space. The gap is continuously evacuated to form and maintain a preset negative pressure value. While maintaining the preset negative pressure value within the gap, if there is a leak in the sealing layer, the negative pressure in the gap outside the sealing layer causes the airflow to flow from the inside of the sealing layer to the outside of the gap and generate characteristic sound waves. The characteristic sound waves are used as input features for detection and identification, and the results are visualized in the form of a cloud map. Specifically, an audio-visual instrument is used to perform full-area leak detection on the inside of the sealing layer. When there is a leak in the sealing layer, the generated characteristic sound waves are used as input features for the audio-visual instrument to detect and identify, and the identification results are visualized in the form of a cloud map.

[0009] The aforementioned technical solution overcomes the barrier of existing technologies that require sealing the entire artificial chamber to achieve full-area detection. This solution replaces the sealing target with a gap that has fewer sealing points. This is because the gap is located between the lining and the sealing layer. Firstly, the sealing layer is designed for sealing, so the number of leaks on the sealing layer is relatively small, and even if there are leaks, they are only small areas that need to be sealed, making the operation relatively easy. Secondly, the sealing layer is closely fitted to the lining, so the space of the through gap between the two is not large, greatly improving the efficiency of vacuuming. In addition, in some technical solutions, air can be injected into the artificial chamber. This simultaneous injection and vacuuming creates negative pressure on the outside of the sealing layer and positive pressure on the inside. This not only facilitates airflow from the inside of the sealing layer to the outside gap, improving the recognizability of characteristic sound waves, but also allows the sealing layer to adhere more tightly to the lining, which is beneficial for the subsequent use of the artificial chamber.

[0010] In this way, a sealed space can be formed in the gap with a small amount of work. Then, the gap is evacuated, and the entire gap has the same negative pressure environment. So, as long as there is a leak point in the entire range of the sealing layer, air will leak. The leak will generate characteristic sound waves. At this time, only an audio-visual instrument is needed to quickly find the location of the characteristic sound waves, and then find the leak point, realizing full-area leak detection.

[0011] Preferably, sealing the through gap on the outside of the sealing layer includes sealing openings and / or channels connected to the gap, such as: equipment maintenance openings, emergency ventilation openings, and other orifices that directly communicate with the gap; and / or drainage channels, auxiliary ventilation channels, pre-buried cable channels, and other grooved channels that communicate with the gap.

[0012] Preferably, sealing the through gap on the outside of the sealing layer includes sealing the channel interface, joint, construction joint and / or expansion joint connected to the gap, such as: the connection interface between the manhole and the gap, the docking interface between the ventilation channel and the gap, the pouring joint between the embedded flange / embedded pipe and the lining, the horizontal construction joint of the segmented pouring of the bottom plate, the vertical construction joint of the layered pouring of the side wall, the expansion joint at the corner of the bottom plate, etc.

[0013] Preferably, the preset negative pressure value is 400-600 Pa.

[0014] Preferably, the preset negative pressure value is 500 Pa.

[0015] It should be noted that most openings, passages, and gaps are sealed during construction. Therefore, in some technical solutions, the openings, passages, or gaps mentioned above are also part of the leak detection process.

[0016] In an improved technical solution, continuous vacuuming of the gap includes: Seal the connection between the vacuum pump and the drain pipe, so that the vacuum pump forms a closed connection with the gap through the drain pipe; Turn on the vacuum pump to perform the evacuation action and evacuate the gap to the preset negative pressure value.

[0017] In this way, when performing the vacuuming step, there is no need to pre-bury pipes (for sealing connection with the vacuum pump) to connect with the gap. Instead, the existing drainage pipe in the artificial chamber is used to specifically seal the connection between the vacuum pump and the drainage pipe, so that the vacuum pump forms a closed connection with the gap through the drainage pipe. In this way, the drainage pipe becomes a necessary structure for the vacuuming step, and there is no need to damage the basic structure of the artificial chamber, such as the sealing layer and lining.

[0018] Specifically, the drain pipe includes: A horizontal tube, arranged parallel to the artificial chamber, has one end exposed to the outside forming a vacuum port, and the vacuum pump is sealed to the vacuum port; and The longitudinal tube is connected to the transverse tube at one end and penetrates the inner surface of the lining at the other end, so that the transverse tube forms a closed connection with the gap through the longitudinal tube.

[0019] Preferably, a valve is provided on the horizontal tube near the vacuum port. This valve can be an intelligent valve or a manual valve.

[0020] Secondly, a device for detecting leakage in the sealing layer of an artificial chamber is provided, comprising: A vacuum pump, connected to the gap, is used to continuously evacuate the gap and maintain a preset negative pressure value within the gap; and A portable acoustic imaging device is used to perform full-area leakage detection on the inner side of the sealing layer while maintaining a preset negative pressure value in the gap, and to identify the characteristic sound waves generated by the outflow of air at the leakage point. The audio-visual device includes a main body and a display screen. The display screen is embedded in the front of the main body and is used to visualize the characteristic sound waves collected by the main body in the form of a cloud map.

[0021] This leak detection device is compatible with artificial chambers consisting of a lining, a sealing layer, and a through-gap between them. The chamber is equipped with a drain pipe connected to the through-gap. Specifically, a vacuum pump creates a vacuum in the gap to provide conditions for the acoustic imaging device to identify leaks across the entire area. That is, a preset negative pressure is formed and maintained within the gap. Once a leak point exists in the sealing layer, regardless of its location or the number of leaks, the negative pressure in the gap outside the sealing layer will cause airflow to flow from the inside of the sealing layer to the outside of the gap, generating characteristic sound waves. At this point, staff can use a portable acoustic imaging device to identify the characteristic sound waves and then quickly and accurately locate the leak point using the cloud map on the display screen.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: By sealing the inherent through gaps in the artificial chamber to create a sealed space, a vacuum is created to generate negative pressure throughout the entire area. This is combined with an acoustic imaging device to detect leaks throughout the sealing layer. The leak point is accurately located through visualization using characteristic acoustic cloud maps, thus breaking through the traditional limitations of local detection, improving vacuuming efficiency, and making operation simpler. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the first embodiment of the present invention, which uses a pre-embedded pipe to vacuum the through gap between the sealing layer and the lining. Figure 2 This is a schematic diagram of a structure for vacuuming the through gap between the sealing layer and the lining using an existing drainage pipe, as shown in the second embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of a portable acoustic imaging device for leak detection in the fourth embodiment of the present invention; Figure 4 This is a schematic diagram showing the arrangement of two leakage points of different properties on the sealing layer in the first experimental example of the present invention; Figure 5 This is a schematic diagram of the detection results in the first experimental example of the present invention, showing that the audio-visual instrument could not detect the leak at the corresponding leak point 1 under vacuum conditions; Figure 6 This is a schematic diagram of a test scenario in the first experimental example of the present invention, in which the audio-visual instrument occasionally captures a signal at a very close distance when the negative pressure is not obvious at the corresponding leakage point 2. Figure 7 This is a schematic diagram of the cloud image of the sound imager detection results when the negative pressure is not obvious at the corresponding leakage point 2 in the first experimental example of the present invention. Figure 8 This is a schematic diagram of a test scenario in the first experimental example of the present invention, in which the corresponding leak point 2 is detected under a continuous vacuum state; Figure 9 This is a schematic diagram of the detection results of the audio-visual instrument effectively locating the leak point at a distance when the corresponding leak point 2 is under continuous vacuum in the first experimental example of the present invention. Figure 10 This is a schematic diagram of the detection results of the audio-visual instrument effectively locating the leak point at a relatively close distance after the vacuuming is stopped in the first experimental example of the present invention.

[0024] The meanings of the labels in the diagram are as follows: 1. Lining; 2. Sealing layer; 3. Gap; 4. Horizontal pipe; 5. Longitudinal pipe; 6. Manhole; 7. Sealing location; 8. Valve; 9. Vacuum interface. Detailed Implementation

[0025] 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.

[0026] First embodiment, Figure 1 The diagram shows the structure of a chamber for vacuuming via pre-embedded pipes. The chamber includes a lining 1, a sealing layer 2, and a manhole 6 (a small personnel passage opening on one side of the chamber), which are the basic structures of the chamber. Figure 1 In the process, the sealing layer 2 is connected to the lining 1 in a dot matrix manner. Specifically, on the surface of the lining 1 facing the inner side of the chamber, there are several fixed points arranged regularly or irregularly at a preset interval. The sealing layer 2 is only attached and fixed to the lining 1 at these fixed points. The back of the sealing layer 2 in the other non-fixed point areas is naturally separated from the surface of the lining 1, and the separated areas between each fixed point are interconnected without any separation. In the end, the sealing layer 2 and the lining 1 form an integral continuous, unblocked through gap 3.

[0027] Due to the need for leak detection, in this embodiment, a hole is made in the sealing layer 2. This hole is used to install the pre-embedded pipe, and the pre-embedded pipe is properly sealed after installation (especially the gap formed between the hole and the pre-embedded pipe). The specific steps for implementing this embodiment are as follows: S1.1. Use a sealing medium or sealing component to seal the sealing position 7 between the manhole 6 and the gap 3. Here, the sealing position 7 refers to the joint between the manhole 6 and the lining 1, and the circumferential joint between the sealing layer 2 and the manhole 6. For example, a water-swellable sealing strip can be used to fill the annular joint between the manhole 6 and the lining 1, and then polyurethane sealant can be used as the sealing medium to fully seal the joint. The joint between the sealing layer 2 and the manhole 6 should be edged and sealed with sealant to strengthen the seal. It should be noted that the sealing position 7 can be more than one type of joint. Figure 1 As shown, other locations that need to be sealed can also be sealed. The ultimate goal is to seal the through gap 3 on the outside of the sealing layer 2, so that the gap 3 forms a closed space.

[0028] S1.2. Transport or lift the vacuum pump through manhole 6 to the location of the pre-embedded pipeline. Then, connect one end of the high-pressure negative pressure resistant connecting pipe of the vacuum pump to the vacuum pump's suction port using a quick-connect sealing joint. Embed a fluororubber sealing gasket in the joint and tighten it to lock it in place. Next, coaxially connect the other end of the connecting pipe to the interface of the pre-embedded pipeline mentioned above, and fix it by threading or clamping to ensure a seamless connection. After confirming that there is no leakage, open the control valve of the pre-embedded pipeline, allowing the vacuum pump to connect with the through-type gap 3 through the pre-embedded pipeline. Then, turn on the vacuum pump and continuously evacuate the gap 3 to form and maintain a preset negative pressure value within the gap 3. The preset negative pressure value is 400-600 Pa, preferably 500 Pa. Scenario 1: 400 Pa is the lower limit of the range, which can only create a weak negative pressure environment. Its advantage lies in the extremely low load on the vacuum pump for evacuation and maintaining negative pressure, resulting in minimal energy consumption. However, the airflow velocity is slow and the sound wave intensity is weak. For tiny leaks (such as pinholes), the signal strength of the airflow sound is below the effective recognition threshold of the audio-visual imaging device, easily leading to signal loss, blurry audio-visual imaging cloud images, and unclear outlines. In other words, it is impossible to accurately locate tiny leaks; only a qualitative judgment can be made that there is a leak in sealing layer 2.

[0029] In scenario two, 500 Pa is the median and preferred value within the range. The moderate negative pressure ensures uniform airflow at both minor and conventional leak points. The resulting characteristic sound wave intensity falls within the optimal recognition range of the audio-visual imaging device, resulting in clear and highly recognizable sound signals. The audio-visual imaging device can quickly capture signals and generate cloud maps with precise contours and clear boundaries, minimizing leak point location errors. Furthermore, the vacuum pump's evacuation load is moderate. Under normal circumstances, the leakage compensation rate of gap 3 at this negative pressure matches the vacuum pump's evacuation rate, easily maintaining pressure stability without frequent vacuum pump start-stop cycles, ensuring high reliability during continuous operation.

[0030] Scenario 3: 600pa is the upper limit of the range. The negative pressure is too high, the airflow speed is fast, and the sound wave intensity is high. It has the most obvious effect on enhancing the sound signal of extremely small leak points (such as micron-sized pinholes). However, the high negative pressure will cause the sound wave signals of some leak points to be easily superimposed and reflected, which will cause artifacts in the sound imager cloud map and increase the probability of misjudging the leak point.

[0031] S1.3. Maintaining a pressure of 500 Pa within gap 3 (maintaining 500 Pa does not mean keeping it constant at 500 Pa, but rather allowing fluctuations within a certain range, preferably ±10%), the operator can use a handheld audio-visual device to perform full-area leakage detection on the inner side of the sealing layer 2 while walking within the chamber from the inside out or from the outside in. If a leak point exists in the sealing layer 2, the negative pressure within the gap 3 on the outer side of the sealing layer 2 causes airflow to flow from the inside of the sealing layer 2 to the outside of the gap 3, generating characteristic sound waves. The audio-visual device uses these characteristic sound waves as input features for detection and identification, and visualizes the identification results as a cloud map. Specifically, the audio-visual device mainly uses an array of acoustic sensors to measure the location and radiation state of the sound emitted from the leak point, visually presenting the collected sound (i.e., characteristic sound waves) on the screen as a cloud map, effectively measuring the sound field distribution. The sound field map is superimposed with the visible light image to form an image similar to a satellite cloud map, displaying the location of the leak point and the sound intensity.

[0032] In some embodiments, although the walking path can be from the inside out or from the outside in, standardized scanning paths and posture specifications should be established and followed to ensure no blind spots in the detection. Specifically, the operator needs to move at a constant speed along the axis of the chamber in a zigzag or parallel path, ensuring that the scanning area between two parallel paths overlaps by about 30% to compensate for the sensitivity attenuation of the acoustic imager in the edge area. During the movement, the handheld acoustic imager should be kept with the lens axis approximately perpendicular to the surface of the sealing layer 2 under test, and the distance is generally recommended to be kept stable between 1 and 3 meters. At the same time, the superposition effect of the acoustic cloud map and the optical image should be observed in real time through the screen of the acoustic imager. In suspected areas, the operator can pause briefly, move back and forth slightly, or change the angle for re-examination.

[0033] Simple walking detection only allows for immediate observation. In some embodiments, spatial positioning and automatic data labeling are integrated. Operators can be equipped with vests or devices integrating ultra-wideband (UWB) or laser SLAM positioning modules, which are connected to the audio-visual system via Bluetooth or Wi-Fi. In this way, while generating an acoustic cloud map, the audio-visual system automatically labels each frame of the image and each high sound pressure level signal point with precise spatial coordinates (X, Y, Z). All detection data (including video stream, sound pressure level data, location information, and timestamps) is recorded and stored synchronously. Afterwards, the entire detection process can be replayed in the software, and the location of each leak point can be accurately reconstructed in the 3D model of the chamber, generating a leak point distribution map with coordinates, providing precise navigation for subsequent maintenance and construction.

[0034] In some embodiments, augmented reality (AR) intelligent assistance and automated report generation can be introduced to improve detection efficiency and consistency. Using AR glasses upgraded with an audio-visual system, operators can observe the real-world scene while simultaneously seeing virtual guidance information overlaid by the system in real time: for example, preset scanning path arrows, color distinctions between detected and undetected areas, and highlighted boxes for suspicious areas initially identified by the system based on acoustic signal characteristics. This significantly reduces reliance on operator memory and experience. After detection, the software can automatically analyze the entire data, filter out effective leakage points, and fill in their location, maximum sound pressure level, spectral characteristics, optical images, and other information into a standardized report template, generating a preliminary draft detection report with one click. Human review and confirmation are then required, greatly reducing subsequent data processing time.

[0035] Second embodiment, Figure 2 The diagram shows the structure of a chamber for achieving vacuuming through a drainage pipe. The chamber includes a lining 1, a sealing layer 2, and a manhole 6 (a small personnel passage opening on one side of the chamber), which are the basic structures of the chamber. Figure 2 In the middle, the sealing layer 2 is connected to the lining 1 in a dot matrix manner, so that the sealing layer 2 and the lining 1 form an integral continuous, unblocked through gap 3.

[0036] In this embodiment, to avoid damaging the sealing layer 2, a drain pipe is utilized. Specifically, the drain pipe includes: Horizontal pipe 4, arranged parallel to the artificial chamber, with the exposed end of horizontal pipe 4 forming a vacuum port 9, and the vacuum pump sealed to the vacuum port 9; and The longitudinal pipe 5 is connected to the horizontal pipe 4 at one end and to the inner surface of the lining 1 at the other end, so that the horizontal pipe 4 and the gap 3 are connected in a closed manner through the longitudinal pipe 5.

[0037] Specifically, continuous vacuuming of gap 3 includes: Seal the vacuum pump to the drain pipe (vacuum port 9) so that the vacuum pump forms a closed connection with the gap 3 through the drain pipe (horizontal pipe 4 and vertical pipe 5); Turn on the vacuum pump to perform the evacuation action, and evacuate gap 3 to the preset negative pressure value. The specific operation process has been disclosed in the first embodiment, so it will not be repeated here.

[0038] In some embodiments, a valve 8 is installed on the horizontal pipe 4 near the vacuum port 9. This valve 8 can be an intelligent valve, with a built-in high-precision sensor that monitors the pressure in the gap 3 in real time and compares it with a preset negative pressure value (e.g., 500 Pa) via an embedded microcontroller. The system employs a PID control algorithm to dynamically adjust the opening of the valve 8, thereby precisely controlling the airflow resistance and intelligently compensating for pressure fluctuations caused by changes in leakage, automatically maintaining the negative pressure in the gap 3 within the optimal range. This ensures the absolute stability and consistency of the acoustic excitation conditions for leakage, significantly improves the quality of the detection signal and the reliability of the results, while also achieving energy-saving operation of the vacuum pump and system protection.

[0039] In the third embodiment, compared to the first and second embodiments, an air pump connected to the manhole 6 of the artificial chamber is introduced, and it operates synchronously with the vacuum pump that extracts air from the gap 3. Specifically, the air pump fills the sealed chamber with air, making its pressure slightly higher than atmospheric pressure (creating positive pressure); at the same time, the vacuum pump continuously extracts air from the gap 3 between the sealing layer 2 and the lining 1, making its pressure lower than atmospheric pressure (maintaining negative pressure). The primary direct effect of this operation is to create a stable pressure differential environment with a defined direction, significant gradient, and precise controllability on both sides of the sealing layer 2 to be tested.

[0040] Based on the aforementioned stable pressure difference, the physical process of leakage is actively enhanced. Specifically, driven by the combined positive pressure inside the sealing layer 2 and the negative pressure outside, air is forced and continuously flows unidirectionally from inside the chamber through any tiny cracks or defects that may exist on the sealing layer 2 to the gap 3 on the outside of the sealing layer 2. This pressure difference directly amplifies the intensity of the original pressure pulsation generated by the airflow at the leakage point, thereby radiating a stronger and more distinctive acoustic signal. In addition, the positive and negative pressures applied to both sides of the sealing layer 2 are essentially equivalent to applying a uniform, perpendicular force to the surface of the entire structure. This mechanical action causes the flexible sealing layer 2 to deform globally and conform to the wall of the lining 1 under this pressure difference, effectively eliminating any possible installation wrinkles or local voids, thus providing additional assurance for the reliability of the waterproof seal for the long-term use of the artificial chamber.

[0041] Fourth embodiment, Figure 3 An acoustic imaging device for detecting leaks in the sealing layer 2 of an artificial chamber is shown. This leak detection device is adapted to an artificial chamber consisting of a lining 1, a sealing layer 2, and a through gap 3 between them, and includes: A vacuum pump, connected to gap 3, is used to continuously evacuate gap 3 and maintain a preset negative pressure value within gap 3; and A portable acoustic imaging device is used to perform full-area leakage detection on the inner side of the sealing layer 2 while maintaining a preset negative pressure value in the gap 3, and to identify the characteristic sound waves generated by the outflow of air at the leakage point. in, Figure 3 The audio-visual device includes a main body and a display screen. The display screen is embedded in the front of the main body and is used to visualize the characteristic sound waves collected by the main body in the form of a cloud map.

[0042] First experimental example, Figure 4 Two leak points are shown, specifically: Leak point 1 was caused by a tool falling during construction. There is hot melt adhesive behind this leak point, which is tightly attached to the steel plate. Leak point 2 is a deliberately created leak point; there is no hot melt adhesive at the bottom, and it is slightly bulging.

[0043] Figure 5 The results of the acoustic imaging test for leak point 1 are shown. When a vacuum pump was used to evacuate gap 3 for an extended period of time, there was no suction sound at leak point 1 regardless of whether the vacuum pump was running (it could not be heard or felt by touch). Leak point 1 could not be detected by the acoustic imaging device. (There was no leak point 2 at this time.) Figure 6 and Figure 7 The results of the acoustic imaging test for leak point 2 are shown. When the negative pressure is not significant (vacuum pump is off for a long time), there is no obvious sound of air leakage at leak point 2, but you can clearly feel gas being drawn in when you touch it with your finger. Using an acoustic imaging device, at a high sensitivity setting, leak point 2 can be occasionally detected (within 0.5 meters).

[0044] Figure 8 , Figure 9 and Figure 10 The results of the acoustic imaging test for leak point 2 are shown in both cases. A) During continuous vacuuming, a clear leaking sound was heard at leak point 2, but the vacuum pump being on caused auditory interference. An acoustic imaging device was used. (See attached image). Figure 9 It can effectively locate within a 5-meter range, and the signal is very clear. B. After the vacuuming stops, the sound of leakage is barely noticeable to the human ear. An audio-visual recorder is used; see [link / reference]. Figure 10 It can effectively locate within a 2-meter range, and the signal is very clear.

[0045] Conclusion: When there is an adhesive layer behind the leak point or it is blocked, vacuuming cannot produce the sound of gas flow, making it impossible to detect with an acoustic imaging device; when the outer side of the sealing layer 2 cannot maintain a certain degree of vacuum, even if there is a clear gas flow (without sound) when touching the leak point, the acoustic imaging device can occasionally capture the leak point under high sensitivity, but there is signal interference; when the outer side of the sealing layer 2 can maintain a certain degree of vacuum, and there is a clear sound of gas flow at the leak point, even if the sound is very weak, and there is other interference in the detection environment, the acoustic imaging device can accurately capture the location of the leak point, and the signal is stable.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for detecting leaks in a mine seal, comprising: include: The through gap on the outside of the sealing layer is sealed to form a closed space. The gap is continuously evacuated to form and maintain a preset negative pressure value. Full-area leakage detection is performed while maintaining the preset negative pressure value within the gap. If there is a leakage point in the sealing layer, the negative pressure in the gap outside the sealing layer causes the airflow to flow from the inside of the sealing layer to the outside gap and generate characteristic sound waves. The characteristic sound waves are used as input features for detection and identification, and the results are visualized in the form of a cloud map.

2. The artificial chamber sealing layer leakage detection process according to claim 1, characterized in that, Sealing through gaps on the outside of the sealing layer includes closing openings and / or channels connected to the gaps.

3. The artificial chamber sealing layer leakage detection process according to claim 1, characterized in that, Sealing through gaps on the outside of the sealing layer includes sealing off channels, joints, construction joints, and / or expansion joints connected to the gaps.

4. The artificial chamber sealing layer leakage detection process according to claim 1, characterized in that, Continuous vacuuming of the gap includes: The vacuum pump is sealed to the pre-embedded pipe, so that the vacuum pump forms a closed connection with the gap through the pre-embedded pipe; Turn on the vacuum pump to perform the evacuation action and evacuate the gap to the preset negative pressure value.

5. The artificial chamber sealing layer leakage detection process according to claim 1, characterized in that, Continuous vacuuming of the gap includes: Seal the connection between the vacuum pump and the drain pipe, so that the vacuum pump forms a closed connection with the gap through the drain pipe; Turn on the vacuum pump to perform the evacuation action and evacuate the gap to the preset negative pressure value.

6. The artificial chamber sealing layer leakage detection process according to any one of claims 1, 4, and 5, characterized in that, The preset negative pressure value is 400-600 Pa.

7. The artificial chamber sealing layer leakage detection process according to claim 4, characterized in that, The drain pipe includes: Horizontal tubes are installed parallel to the artificial chambers; and The longitudinal tube is connected to the transverse tube at one end and penetrates the inner surface of the lining at the other end, so that the transverse tube forms a closed connection with the gap through the longitudinal tube.

8. The artificial chamber sealing layer leakage detection process according to claim 1, characterized in that, The end of the horizontal tube exposed to the outside forms a vacuum port, and the vacuum pump is sealed to the vacuum port.

9. The artificial chamber sealing layer leakage detection process according to claim 8, characterized in that, A valve is installed on the horizontal tube near the vacuum port.

10. A leakage detection device for the sealing layer of an artificial chamber, adapted to an artificial chamber consisting of a lining, a sealing layer, and a through gap between the two, characterized in that, include: A vacuum pump, connected to the gap, is used to continuously evacuate the gap and maintain a preset negative pressure value within the gap. and A portable acoustic imaging device is used to perform full-area leakage detection on the inner side of the sealing layer while maintaining a preset negative pressure value in the gap, and to identify the characteristic sound waves generated by the outflow of air at the leakage point. The audio-visual device includes a main body and a display screen. The display screen is embedded in the front of the main body and is used to visualize the characteristic sound waves collected by the main body in the form of a cloud map.

Images