Active phased array digital seismic detection system for mining working plane of mine and tunnel

Abstract

The invention provides an active phased array digital seismic detection system for advanced detection of tunnels, mining roadways and working planes, and relates to the field of seismic exploration. Comprising a seismic wave transmitting end, a seismic wave receiving end and a data processing end. The seismic wave transmitting end controls a seismic source array to emit directional plane waves through a controller based on an array formed by a series of controlled seismic sources; a seismic wave receiving end receives a signal reflected by the directional plane wave when encountering a front abnormal geological structure by using a high-density arranged detector array or a distributed optical cable; and the data processing end operates a specific algorithm and performs advanced detection imaging on abnormal geological structures and coal seam roof and floor forms in front of the tunneling face and the stoping face, side walls and the like. Then, on the basis of an artificial intelligence system, a complex geological structure and an abnormal area are analyzed and recognized, a dynamic advanced detection and data interpretation system is provided for tunnel and roadway tunneling and stoping faces, and the system serves for a geological guarantee system and intelligent construction of tunnels, mine roadways and stoping projects.

Description

Technical Field

[0001] This application relates to the field of seismic exploration technology, and in particular to an active phased array digital seismic detection system for mining and tunnel excavation faces. Background Technology

[0002] With the deepening exploration and development of underground mineral resources, and the practical needs of energy, mining, transportation, water conservancy, and military projects, underground tunnel and mining engineering have developed on a large scale. The frequency of these projects crossing high-risk geological areas such as fault zones and water-rich regions is also increasing. Therefore, there is an urgent need for geological space exploration and real-time monitoring ahead of underground mining projects to support safe tunneling and intelligent tunneling with fewer or no personnel. Tunneling and mining processes often face unknown geological structures and hidden hazards. During tunneling and mining, the unloading effect of excavation can cause stress concentration in the surrounding rock, leading to its instability. Therefore, exploring the geological structure ahead of the working face and monitoring the stability of the surrounding rock in tunnels and mining roadways during tunneling and mining are crucial requirements for ensuring safe tunneling and mining operations, and have significant research and application value.

[0003] Traditional methods for advanced detection in tunnels, mining roadways, and mining operations mainly include seismic methods, electromagnetic methods, and drilling methods. Among these, drilling methods are the most accurate, but they require a period of downtime, are expensive, and have a long implementation cycle, making it impossible to complete detection within a single maintenance shift. Electromagnetic methods are often affected by numerous metal devices and supports underground, frequently creating blind spots that severely impact resolution and accuracy. Furthermore, tunnel excavation involves a full-space effect, with various strata response signals superimposed, making it difficult to identify the location of anomalies. Seismic methods, including channel wave, TSP, and TRT, utilize underground explosive (or hammer) sources for detection, which carries certain risks (or has relatively low energy), limiting detection distance and resolution.

[0004] In recent years, the development of seismic detection methods during excavation and mining has utilized the vibration signals generated by mining equipment cutting through rock or coal strata. Geophones are then deployed in tunnels or mining roadways to detect geological structures and wave velocity anomalies ahead of and along the working face. While this method eliminates the need for machine shutdown, blasting, and drilling, the seismic sources generated by mining machinery are complex and highly random. The limited space in the tunnels restricts observation, resulting in incomplete wavefield records and severely impacting the resolution of imaging results. Furthermore, it makes it difficult to accurately identify and locate geological anomalies in different orientations. In fact, the biggest common problem in traditional tunnel and mining engineering advanced detection, from the transmitting perspective, is the lack of effective, interference-resistant seismic sources; and from the receiving perspective, it is the limitation of the "one-dimensional space" of the tunnel or roadway, leading to a single observation orientation, small aperture, and difficulty in applying high-density array observations and the high-resolution imaging methods they provide. Summary of the Invention

[0005] In view of the above problems, this application proposes an active phased array digital seismic detection system for mining and tunnel excavation faces to overcome the shortcomings of the prior art.

[0006] In a first aspect, embodiments of this application provide an active phased array digital seismic detection system for mining and tunnel excavation faces, comprising: a seismic wave transmitting end, a seismic wave receiving end, and a data processing end; The seismic wave emitting end includes: multiple controlled seismic sources installed at multiple locations within the tunnel, the multiple controlled seismic sources forming a seismic source array, and the frequency, phase and time delay of the seismic source array controlled by a controller to emit directional plane waves to detect geological structures and anomalous areas; The seismic wave receiver includes multiple receiving devices installed at preset locations, used to receive seismic signals reflected back from the geological structures or geological anomalies in front of the working face when the directional plane waves emitted by the seismic wave transmitter encounter the geological structures or geological anomalies in front of the working face; The data processing end is used to process and analyze all wavefield information in the data storage end, to image the geological structures in front of the tunnel face and the tunnel sidewalls and the surrounding area, as well as the geological structures and abnormal areas inside the mining face, and to analyze and identify complex geological structures and events. All wavefield information includes: the directional plane wave and the reflected seismic signal.

[0007] Optionally, the controlled vibration source includes, but is not limited to, a controlled detonation explosive vibration source, an electric spark vibration source, an air gun vibration source, or a controllable vibration source device driven by a motor or hydraulic system. The plurality of receiving devices include, but are not limited to, detector arrays or distributed optical cables; The complex geological structures and events mentioned include, but are not limited to, the analysis and identification of various structures such as faults, folds, fracture zones, collapse columns, voids, igneous rocks, and undulations of the roof and floor of tunnels; the understanding and prediction of various events such as microseismic events, spatial and temporal anomalies of wave velocity, and temporal anomalies of geological structures; and the comprehensive analysis and simulation of various hidden geological disaster-causing factors, including but not limited to water-filled areas, water-conducting channels, stress anomaly areas, and gas-rich areas, as well as the stability of tunnel surrounding rock.

[0008] Optionally, multiple controlled seismic sources form a seismic source array through several controlled seismic wave excitation devices spaced at preset distances. The controller controls the frequency, phase, and time delay of the seismic waves excited by each controlled seismic wave excitation device, so that the emitted seismic signals are superimposed into plane waves that propagate in a direction according to a set emission angle. Each controlled seismic wave excitation device has frequency conversion, phase modulation, and precise time synchronization functions, and the response time to the excitation command issued by the controller is less than 1ms. The controller has programming capabilities. By controlling each controlled seismic source in the seismic source array, it can control the phase shift, time delay, amplitude, and frequency of the emitted seismic waves. By adjusting the emission parameters, the seismic source array can emit directional plane waves and continuously scan within a certain emission angle range. The controller is also used to adjust the waveform encoding of the transmitted signal according to the nature and distance of the detected target, the waveform encoding including amplitude and frequency encoding.

[0009] Optionally, the specific manner in which multiple controlled seismic sources are installed at multiple locations within the tunnel includes: Several controlled seismic sources are installed at fixed intervals within the tunnel, either on the tunnel floor or sidewalls, at the tunnel face, at the working face, or on both sides of the mining face. The controlled seismic sources are connected to each other by cable or wireless means and connected to the controller. The controller synchronizes the time between each controlled seismic source through precise time synchronization and timing methods and sends out seismic wave excitation control signals. The time synchronization and timing methods include, but are not limited to, PTP protocol, GPS, atomic clock, and temperature-controlled crystal oscillator. The controller's transmission parameters include: the excitation waveform, initial frequency, initial phase, and start-up time of each controlled vibration source.

[0010] Optionally, the distributed optical cable includes, but is not limited to, distributed fiber optic acoustic sensing devices; The detector array includes, but is not limited to, densely arranged single-component or three-component detector devices. The spatial sampling interval of the distributed optical cable or the detector array is less than or equal to half the wavelength of the emitted directional plane wave. It receives the seismic signals reflected back from the directional plane wave when it encounters geological structures or anomalous properties in the tunnel, mining roadway, or working face or sidewall, to ensure a complete record of the wave field.

[0011] Optionally, the specific manner in which the plurality of receiving devices are installed at the preset location includes: Multiple distributed fiber optic acoustic sensors are laid on the floor, roof, or sidewalls of tunnels or mining roadways, and tightly coupled to the tunnel or mining roadway walls using cement mortar, polymer materials, or gypsum; or, Multiple three-component or single-component geophones are tightly fixed to the anchor bolts supporting the tunnel or mining roadway to achieve close coupling with the tunnel or roadway wall; or, Simultaneously, multiple distributed fiber optic acoustic sensors and multiple three-component detectors are deployed to integrate high-density, multi-component observations from the distributed fiber optic acoustic sensors and the three-component detectors, thereby achieving complete observation of the seismic wavefield.

[0012] Optionally, the data processing terminal acquires the reflected seismic signal and the directional plane wave in real time and preprocesses them, including storage, filtering, time-frequency analysis, and noise reduction. The data processing terminal inputs pre-installed seismic detection and imaging software for advanced detection, seismic monitoring, and geological anomaly imaging; The data processing terminal identifies the characteristics of abnormal geological structures from the reflected seismic signals, detects and monitors their presence, locates them, performs inversion imaging, estimates the size, shape, orientation, type, and physical properties of abnormal geological bodies, and outputs the identification, location, and attribute feature inversion imaging results of abnormal geological bodies. As detection and monitoring continue, the detection results of abnormal geological bodies are dynamically corrected and updated, and the development of abnormal geological bodies is monitored as tunnel excavation or mining processes progress, as well as the stability of the surrounding rock during tunnel excavation or mining processes. The types of abnormal geological bodies include, but are not limited to, faults, fracture zones, karst caves, collapse columns, goaf areas, and water-rich areas; The physical properties of the anomalous geological bodies include, but are not limited to, longitudinal and transverse wave velocities, anisotropy, and attenuation coefficients.

[0013] Optionally, the methods for advanced detection at the data processing end include, but are not limited to: forward modeling and analysis of the reflection characteristics of anomalous geological bodies and automatic separation from clutter, identification of reflection power spectrum characteristics, analysis of interferometric characteristics of coherent superposition of multi-angle plane waves, waveform-based adaptive filtering optimization, reflection wave imaging, transmission wave imaging, scattered wave imaging, and full waveform inversion. In the process of conducting advance detection using any method, the directional plane wave and the reflected seismic signal are used for interferometric superposition, waveform recognition, wavelet transform, spectrum matching, energy analysis, phase analysis, travel time extraction, and target structure inversion. Artificial intelligence methods are used to identify and extract the amplitude, phase, and energy characteristics of the reflected seismic signal, as well as the interferometric pattern characteristics generated by two or more directional plane waves illuminating the geological structural anomaly area, in order to determine the size, shape, and multi-scale structure of the geological body.

[0014] Optionally, the methods for seismic monitoring at the data processing end include, but are not limited to: time-delay imaging, coma cross-correlation, phase interferometry, spatiotemporal scanning using directionally transmitted and received seismic waves, or interferometric superposition of two or more directionally transmitted plane waves, and periodically or continuously detecting the location, morphology, wave velocity, and other attribute information of geological anomalies.

[0015] Optionally, the multiple controlled seismic sources constitute a seismic source array in the form of a one-dimensional or two-dimensional array; When the source array is constructed in the form of a one-dimensional array, multiple controlled sources are equally spaced along the tunnel extension direction inside the tunnel. The spacing is determined according to the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled sources and the total wiring length are determined by the beamwidth of the directional plane wave. Multiple receiving devices are deployed at equal intervals along the tunnel extension direction inside the tunnel, and are interspersed with multiple controlled seismic sources. The deployment interval and range are determined according to the spatial resolution of the detection and the range to be detected. During the detection process, coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , , by azimuth Take 0 to Mark the directions of the plane waves to be superimposed, where Indicates propagation in a vertically downward direction; The first one-dimensional controlled seismic source, namely Using the controlled source at the location as a reference source, the distance of each controlled source relative to the first one-dimensional controlled source along the undetermined propagation direction is... r i1 for:

[0016] The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation time of each controlled seismic source τ i1 for:

[0017] When the source array is constructed in the form of a two-dimensional array, multiple controlled sources are arranged at equal intervals in the tunnel along the tunnel extension direction in the form of regular quadrilateral or equilateral triangular nodes. The arrangement interval is determined according to the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled sources and the total wiring length are determined by the beamwidth of the directional plane wave. Multiple receiving devices are deployed at equal intervals along the tunnel extension direction inside the tunnel, and are interspersed with multiple controlled seismic sources. The deployment interval and range are determined according to the spatial resolution of the detection and the range to be detected. During the detection process, using horizontal coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , The horizontal azimuth angle between the x-axis and the spherical coordinate system. and vertical azimuth Mark the directions of the plane waves to be superimposed, where The value range is 0 to ; The value range is 0 to , Indicates propagation in a vertically downward direction; The first two-dimensional controlled seismic source, namely Using the controlled source at the location as a reference source, the distance of each controlled source relative to the first two-dimensional source along the undetermined propagation direction is... r i2 for:

[0018] The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation times of each controlled seismic source are:

[0019] In the above formula, τ i2 This indicates the relative advance excitation time of each controlled seismic source.

[0020] The active phased array digital seismic detection system proposed in this application for advanced detection of tunnels, mining roadways, and working faces comprises multiple controlled seismic sources installed at multiple locations within the tunnel, forming a source array. The frequency, phase, and time delay of the source array are controlled by a controller to emit directional plane waves to detect geological structures and anomalous areas. Multiple receiving devices installed at preset locations are used to receive seismic signals reflected back from the geological structures or anomalous areas in front of the working face by the directional plane waves emitted by the seismic wave transmitter. The data processing terminal is used to process and analyze all wavefield information in the data storage terminal, image the geological structures in front of the tunnel face and the tunnel sidewalls and surrounding areas, as well as the geological structures and anomalous areas inside the mining face, and analyze and identify complex geological structures and events.

[0021] Compared with the prior art, the positive effects of this application are: (1) An array consisting of a series of controlled seismic sources and a programmable controller is used to emit seismic plane waves with frequency coding and directional scanning, which overcomes the problems of point source excitation, lack of directionality, lack of frequency coding and inconvenience for subsequent identification and processing of traditional seismic source devices. These controlled seismic excitation devices can be integrated into mining machinery and equipment to realize exploration while mining and exploration while excavating.

[0022] (2) Based on the one-dimensional or two-dimensional layout of controlled seismic sources, a specific method for the relative advance excitation time of each controlled seismic source is creatively proposed, which is a technology that does not yet exist.

[0023] (3) Compared with explosive sources, it is easier to construct, lower in cost, and safer; compared with hammer sources, it has stronger energy and stronger anti-interference capabilities; compared with continuous sources of coal mining machines and tunneling machines, it has better determinism, higher repeatability, and higher signal-to-noise ratio. It completely solves the problem of lack of underground sources. During maintenance shifts, sources and detectors can be deployed for advanced detection. The detection distance can reach 100-300m depending on the lithology of the surrounding rock, effectively guiding the tunneling or mining work of the next production shift.

[0024] (4) By digitally controlling the excitation time, frequency and phase of each sub-source of the array, waveforms are superimposed to form a directional scanning signal. Seismic waves can be directionally emitted in all directions of the tunnel without mechanical adjustment of the array position, truly realizing the "active digital phased array radar" technology in seismological methods.

[0025] (5) By using plane waves for directional scanning to detect geological structures and anomalies in specific directions, distributed optical fibers or three-component geophones are laid at the same location as the seismic radar array to receive the reflected waves of geological structures or anomalies. This can distinguish geological structures or anomalies in different directions. Compared with traditional methods, this overcomes the "azimuth ambiguity" problem that is common in one-dimensional observation of tunnel excavation.

[0026] (6) The presence or absence of reflected waves can be used to determine the presence of a structure; the amplitude and phase characteristics of the reflected waves can be used to determine the size and geometry of the structure; by using the plane wave interferometry superposition method and combining artificial intelligence to identify the interferometric pattern, the strike, dip angle, drop, and water content of the fault fracture zone can be detected in a super-resolution manner. Compared with traditional tunneling detection methods, it has higher resolution and lower false alarm rate. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of an exemplary active phased array digital seismic detection system deployed in a tunnel or roadway excavation face, and a schematic diagram of the structure of an active phased array digital seismic detection system deployed in a tunnel or roadway mining face, as described in this application. Figure 2 This is a flowchart illustrating the workflow of an active phased array digital seismic detection system for mining and tunnel excavation faces, as exemplified in the embodiments of this application. Detailed Implementation

[0028] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0029] This application discloses an active phased array digital seismic detection system for mining and tunnel excavation faces, comprising: a seismic wave transmitting end, a seismic wave receiving end, and a data processing end, wherein: The seismic wave transmitter includes multiple controlled seismic sources installed at multiple locations within the tunnel. These multiple controlled seismic sources form a seismic source array. The frequency, phase, and time delay of the seismic source array are controlled by a controller to emit directional plane waves to detect geological structures and anomalous areas.

[0030] The seismic wave receiver includes multiple receiving devices installed at preset locations, used to receive seismic signals reflected back from the geological structures or geological anomalies in front of the working face when the directional plane waves emitted by the seismic wave transmitter encounter the seismic signals.

[0031] The data processing end is used to process and analyze all wavefield information in the data storage end, to image the geological structures in front of the tunnel face and the tunnel sidewalls and the surrounding area, as well as the geological structures and abnormal areas inside the mining face, and to analyze and identify complex geological structures and events. All wavefield information includes: directional plane waves and reflected seismic signals.

[0032] In one embodiment of this application, the controlled vibration source includes, but is not limited to, a controlled-detonation explosive vibration source, an electric spark vibration source, a gas gun vibration source, a motor- or hydraulically driven controllable vibration source device, etc. Multiple receiving devices include, but are not limited to, detector arrays or distributed optical cables, etc.

[0033] Complex geological structures and events include, but are not limited to, the analysis and identification of various structures such as faults, folds, fracture zones, collapse columns, voids, igneous rocks, and undulations of tunnel roof and floor; the understanding and prediction of various events such as microseismic events, spatial and temporal anomalies of wave velocity, and temporal anomalies of geological structures; and the comprehensive analysis and simulation of various hidden geological disaster-causing factors, including but not limited to water-filled areas, water-conducting channels, stress anomaly areas, and gas-rich areas, as well as the stability of tunnel surrounding rock.

[0034] In one embodiment of this application, multiple controlled seismic sources can preferably be configured into a seismic source array by a number of controlled seismic wave excitation devices spaced at preset distances. Therefore, the frequency, phase, and time delay of the seismic waves excited by each controlled seismic wave excitation device can be controlled by a controller, so that the emitted seismic signals are superimposed into plane waves that propagate in a direction according to a set emission angle.

[0035] Each controlled seismic wave excitation device possesses frequency conversion, phase modulation, and precise time synchronization functions, ensuring a response time of less than 1ms to the excitation command issued by the controller. The controller is programmable, controlling each controlled seismic source in the source array to manage the phase shift, time delay, amplitude, and frequency of the emitted seismic waves. By adjusting the emission parameters, the source array emits directional plane waves that continuously scan within a certain emission angle range. Furthermore, the controller adjusts the waveform encoding of the emitted signal based on the nature and distance of the target being detected; this waveform encoding includes amplitude and frequency encoding.

[0036] In one embodiment of this application, the specific method of installing multiple controlled seismic sources at multiple locations within a tunnel differs from ground-based installation methods due to the special nature of the installation locations, including: Several controlled seismic sources are installed at fixed intervals inside the tunnel, either on the tunnel floor or sidewalls, or at the tunnel face, the working face, or the two sides of the mining face. The controlled seismic sources are connected to each other by cables or wirelessly (e.g., WiFi / 5G / 4G) and connected to a controller.

[0037] The controller synchronizes the time between the controlled seismic sources precisely through accurate time synchronization and timing methods, and sends out seismic wave excitation control signals. These time synchronization and timing methods include, but are not limited to, PTP protocol, GPS, atomic clocks, and temperature-controlled crystal oscillators. The controller's transmission parameters include: the excitation waveform, initial frequency, initial phase, and start-up time of each controlled seismic source.

[0038] In one embodiment of this application, for the receiving end device, the distributed optical cable includes, but is not limited to, distributed fiber optic acoustic sensing devices; the detector array includes, but is not limited to, various devices such as densely arranged single-component or three-component detectors.

[0039] The spatial sampling interval of the distributed optical cable or detector array should be less than or equal to half the wavelength of the emitted directional plane wave. The receiver receives the seismic signals reflected back from the directional plane wave emitted by the seismic wave transmitter when it encounters geological structures or anomalous properties in the tunnel, mining roadway, or working face or sidewall, so as to ensure a complete record of the wave field.

[0040] In one embodiment of this application, the specific method by which multiple receiving devices are installed at preset locations includes: If only distributed fiber optic acoustic sensing devices are used, multiple distributed fiber optic acoustic sensing devices are laid on the floor, roof or sidewall of the tunnel or mining roadway, and tightly coupled to the tunnel or mining roadway wall using cement mortar, polymer materials or gypsum.

[0041] Alternatively, if only a detector array is used, multiple three-component or single-component detectors are densely fixed to the anchor bolts supporting the tunnel or mining roadway to achieve tight coupling with the tunnel or roadway wall.

[0042] Alternatively, if distributed fiber optic acoustic sensing devices and detector arrays are used simultaneously, multiple distributed fiber optic acoustic sensing devices and multiple three-component detectors are deployed at the same time, and the high-density, multi-component observations of the distributed fiber optic acoustic sensing devices and three-component detectors are integrated to achieve complete observation of the seismic wavefield.

[0043] In one embodiment of this application, during data processing, the data processing terminal acquires reflected seismic signals and emitted directional plane waves in real time and performs preprocessing, including storage, filtering, time-frequency analysis, and noise reduction. The data processing terminal then inputs pre-installed seismic detection and imaging software for advanced detection, seismic monitoring, and geological anomaly imaging.

[0044] The data processing unit identifies the characteristics of abnormal geological structures from the reflected seismic signals, detects and monitors their presence, locates them, performs inversion imaging, estimates the size, shape, orientation, type, and physical properties of abnormal geological bodies, and outputs the identification, location, and attribute feature inversion imaging results of abnormal geological bodies. As detection and monitoring continue, the detection results of abnormal geological bodies are dynamically corrected and updated, and the development of abnormal geological bodies is monitored as tunnel excavation or mining processes progress, as well as the stability of the surrounding rock during tunnel excavation or mining processes.

[0045] Among these, the types of so-called anomalous geological bodies include, but are not limited to, faults, fracture zones, karst caves, collapse columns, goaf areas, water-rich areas, etc.; the physical properties of anomalous geological bodies include, but are not limited to, longitudinal and transverse wave velocities, anisotropy, attenuation coefficients, etc.

[0046] In one embodiment of this application, the method for advanced detection at the data processing end includes, but is not limited to: forward modeling and analysis of the reflection characteristics of anomalous geological bodies and automatic separation from clutter, identification of reflection power spectrum characteristics, analysis of interferometric characteristics of coherent superposition of multi-angle plane waves, waveform-based adaptive filtering optimization, reflection wave imaging, transmission wave imaging, scattering wave imaging, full waveform inversion, etc.

[0047] In the aforementioned methods of advanced detection, during the advanced detection process using any of the methods, the emitted directional plane waves and the reflected seismic signals are used for interferometric superposition, waveform recognition, wavelet transform, spectrum matching, energy analysis, phase analysis, travel time extraction, and target structure inversion. Artificial intelligence methods are used to identify and extract the amplitude, phase, and energy characteristics of the reflected seismic signals, as well as the interferometric pattern characteristics generated by two or more directional plane waves illuminating the geological structural anomaly area, in order to determine the size, shape, and multi-scale structure of the geological body.

[0048] In one embodiment of this application, the method for seismic monitoring at the data processing end includes, but is not limited to: time-delay imaging, coma cross-correlation, phase interferometry, spatiotemporal scanning using directionally transmitted and received seismic waves, or interferometric superposition of two or more directionally transmitted plane waves, periodically or continuously detecting the location, morphology, wave velocity, and other attribute information of geological anomalies. This seismic monitoring method differs slightly from the previously mentioned seismic detection method, which images static geological structures; while this seismic monitoring method performs real-time, continuous dynamic monitoring of geological structures. Therefore, the specific methods used differ.

[0049] In one embodiment of this application, multiple controlled seismic sources can be arranged in the form of a one-dimensional or two-dimensional array to form a seismic source array. The choice between a one-dimensional array and a two-dimensional array depends on the distance of the area to be detected and whether the tunnel space conditions allow it.

[0050] In this configuration, when the seismic source array is constructed in the form of a one-dimensional array, multiple controlled seismic sources are deployed at equal intervals along the tunnel's extension direction. The spacing between these sources is determined based on the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled seismic sources and the total length of the wiring are determined by the beamwidth of the directional plane wave. Preferably, the position of each controlled seismic source can also be recorded using high-precision positioning equipment (such as RTK).

[0051] Multiple receiving devices are deployed at equal intervals along the tunnel's extension direction, interspersed with multiple controlled seismic sources. They should not be placed too close to the controlled seismic sources to avoid amplitude limiting issues. The spacing and range of the receiving devices are determined based on the spatial resolution of the detection and the area to be detected. Generally, the distribution range of the detectors should be much larger than the distribution range of the controlled seismic sources. Alternatively, high-precision positioning equipment (such as RTK) can be used to record the positions of each receiving device.

[0052] The controlled seismic source and controller are connected by a cable and powered by a high-power mobile power supply or downhole power source. The detector operates independently or is connected to the controller wirelessly.

[0053] During the detection process, coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , , by azimuth Take 0 to Mark the directions of the plane waves to be superimposed, where It indicates propagation in a vertically downward direction.

[0054] The first one-dimensional controlled seismic source, namely Using the controlled source at the location as the reference source, the distance of each controlled source relative to the first one-dimensional controlled source along the undetermined propagation direction is... r i1 for:

[0055] The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation time of each controlled seismic source τ i1 for:

[0056] When a seismic source array is constructed in the form of a two-dimensional array, multiple controlled seismic sources are arranged at equal intervals in a quadrilateral or equilateral triangular pattern along the tunnel's extension direction. The spacing is determined based on the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled seismic sources and the total length of the wiring are determined by the beamwidth of the directional plane wave. Alternatively, a high-precision positioning device (such as RTK) can be used to record the position of each controlled seismic source.

[0057] Multiple receiving devices are deployed at equal intervals along the tunnel's extension direction, interspersed with multiple controlled seismic sources. The spacing and range of these devices are determined based on the spatial resolution of the detection and the area to be detected. The receiving devices should not be placed too close to the controlled seismic sources to avoid amplitude limiting issues. Generally, the distribution range of the receiving devices should be much larger than the distribution range of the controlled seismic sources. Preferably, high-precision positioning equipment (such as RTK) can also be used to record the positions of each receiving device.

[0058] During the detection process, using horizontal coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , The horizontal azimuth angle between the x-axis and the spherical coordinate system. and vertical azimuth (Vertical azimuth angle consistent with the one-dimensional case) Mark the directions of the plane waves to be superimposed, where The value range is 0 to ; The value range is 0 to , It indicates propagation in a vertically downward direction.

[0059] The first two-dimensional controlled seismic source, namely Using the controlled source at the location as a reference source, the distance of each controlled source relative to the first two-dimensional source along the undetermined propagation direction is... r i2 for:

[0060] The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation times of each controlled seismic source are:

[0061] In the above formula, τ i2 This indicates the relative advance excitation time of each controlled seismic source. It is understandable that the parameters that need to be recorded during the deployment of the controlled seismic sources and receiving equipment mainly include: (1) The precise spatial location (accuracy, latitude, altitude, etc.) of each controlled seismic source.

[0062] (2) The precise spatial location (accuracy, latitude, altitude, etc.) of each receiving device.

[0063] (3) The layout of each receiving device (tilt angle, azimuth angle, etc.).

[0064] In one embodiment of this application, to better understand the active phased array digital seismic detection system of this application, refer to... Figure 1 The diagram shows an exemplary active phased array digital seismic detection system deployed at a tunnel or roadway excavation face, and an exemplary active phased array digital seismic detection system deployed at a tunnel or roadway mining face. Figure 1 In the example, distributed optical fiber and a three-component seismograph are used as the seismic wave receivers. The source array in the seismic wave transmitter is controlled by a control unit (i.e., a controller) to emit directional plane waves, and the reflection area can reflect the seismic signal back.

[0065] In one embodiment of this application, the workflow of the active phased array digital seismic detection system for the entire mine and tunnel excavation face can be referred to Figure 2 The flowchart shown illustrates that the data processing end controls the time delay, phase, and amplitude of the seismic wave transmitter through a controller, thereby emitting a directional plane wave.

[0066] The seismic wave receiver receives the reflected seismic signals and transmits them to the data processing unit in real time using the controller. The data processing unit preprocesses the received signals (filtering, noise reduction, time-frequency analysis, etc.), performs reflected wave identification and extraction, amplitude and phase feature identification, and cluster interferometry pattern processing, and realizes the identification of the presence or absence of abnormal geological structures, the orientation and location of abnormal geological structures, the estimation of the size and shape of abnormal geological structures, and the inversion of the attributes of abnormal geological structures.

[0067] In summary, the active phased array digital seismic detection system for mining and tunnel excavation faces proposed in this application comprises multiple controlled seismic sources installed at multiple locations within the tunnel, forming a source array. A controller controls the frequency, phase, and time delay of the source array to emit directional plane waves to detect geological structures and anomalous areas. Multiple receiving devices installed at preset locations receive seismic signals reflected back from the geological structures or anomalous areas ahead of the working face by the directional plane waves emitted from the seismic wave transmitter. The data processing unit processes and analyzes all wavefield information stored in the data storage unit, imaging the geological structures ahead of the tunnel face and the tunnel sidewalls and surrounding areas, as well as the geological structures and anomalous areas inside the mining face, and analyzing and identifying complex geological structures and events.

[0068] Compared with the prior art, the positive effects of this application are: (1) An array consisting of a series of controlled seismic sources and a programmable controller is used to emit seismic plane waves with frequency coding and directional scanning, which overcomes the problems of point source excitation, lack of directionality, lack of frequency coding and inconvenience for subsequent identification and processing of traditional seismic source devices. These controlled seismic excitation devices can be integrated into mining machinery and equipment to realize exploration while mining and exploration while excavating.

[0069] (2) Based on the one-dimensional or two-dimensional layout of controlled seismic sources, a specific method for the relative advance excitation time of each controlled seismic source is creatively proposed, which is a technology that does not yet exist.

[0070] (3) Compared with explosive sources, it is easier to construct, lower in cost, and safer; compared with hammer sources, it has stronger energy and stronger anti-interference capabilities; compared with continuous sources of coal mining machines and tunneling machines, it has better determinism, higher repeatability, and higher signal-to-noise ratio. It completely solves the problem of lack of underground sources. During maintenance shifts, sources and detectors can be deployed for advanced detection. The detection distance can reach 100-300m depending on the lithology of the surrounding rock, effectively guiding the tunneling or mining work of the next production shift.

[0071] (4) By digitally controlling the excitation time, frequency and phase of each sub-source of the array, waveforms are superimposed to form a directional scanning signal. Seismic waves can be directionally emitted in all directions of the tunnel without mechanical adjustment of the array position, truly realizing the "active digital phased array radar" technology in seismological methods.

[0072] (5) By using plane waves for directional scanning to detect geological structures and anomalies in specific directions, distributed optical fibers or three-component geophones are laid at the same location as the seismic radar array to receive the reflected waves of geological structures or anomalies. This can distinguish geological structures or anomalies in different directions. Compared with traditional methods, this overcomes the "azimuth ambiguity" problem that is common in one-dimensional observation of tunnel excavation.

[0073] (6) The presence or absence of reflected waves can be used to determine the presence of a structure; the amplitude and phase characteristics of the reflected waves can be used to determine the size and geometry of the structure; by using the plane wave interferometry superposition method and combining artificial intelligence to identify the interferometric pattern, the strike, dip angle, drop, and water content of the fault fracture zone can be detected in a super-resolution manner. Compared with traditional tunneling detection methods, it has higher resolution and lower false alarm rate.

[0074] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0075] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0076] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims. All of these forms are within the protection scope of this application.

Claims

1. An active phased array digital seismic detection system for mining and tunnel excavation faces, characterized in that, include: Seismic wave transmitter, seismic wave receiver, and data processing unit; The seismic wave emitting end includes: multiple controlled seismic sources installed at multiple locations within the tunnel, the multiple controlled seismic sources forming a seismic source array, and the frequency, phase and time delay of the seismic source array controlled by a controller to emit directional plane waves to detect geological structures and anomalous areas; The seismic wave receiver includes multiple receiving devices installed at preset locations, used to receive seismic signals reflected back from the geological structures or geological anomalies in front of the working face when the directional plane waves emitted by the seismic wave transmitter encounter the geological structures or geological anomalies in front of the working face; The data processing end is used to process and analyze all wavefield information in the data storage end, to image the geological structures in front of the tunnel face and the tunnel sidewalls and the surrounding area, as well as the geological structures and abnormal areas inside the mining face, and to analyze and identify complex geological structures and events. All wavefield information includes: the directional plane wave and the reflected seismic signal.

2. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 1, characterized in that, The controlled vibration source includes, but is not limited to, controlled detonation explosive vibration source, electric spark vibration source, air gun vibration source, and motor- or hydraulically driven controllable vibration source device. The plurality of receiving devices include, but are not limited to, detector arrays or distributed optical cables; The complex geological structures and events mentioned include, but are not limited to, the analysis and identification of various structures such as faults, folds, fracture zones, collapse columns, voids, igneous rocks, and undulations of the roof and floor of tunnels; the understanding and prediction of various events such as microseismic events, spatial and temporal anomalies of wave velocity, and temporal anomalies of geological structures; and the comprehensive analysis and simulation of various hidden geological disaster-causing factors, including but not limited to water-filled areas, water-conducting channels, stress anomaly areas, and gas-rich areas, as well as the stability of tunnel surrounding rock.

3. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 1, characterized in that, Multiple controlled seismic sources form a seismic source array through several controlled seismic wave excitation devices spaced at preset distances. The controller controls the frequency, phase, and time delay of the seismic waves excited by each controlled seismic wave excitation device, so that the emitted seismic signals are superimposed into plane waves that propagate in a direction according to a set emission angle. Each controlled seismic wave excitation device has frequency conversion, phase modulation, and precise time synchronization functions, and the response time to the excitation command issued by the controller is less than 1ms. The controller has programming capabilities. By controlling each controlled seismic source in the seismic source array, it can control the phase shift, time delay, amplitude, and frequency of the emitted seismic waves. By adjusting the emission parameters, the seismic source array can emit directional plane waves and continuously scan within a certain emission angle range. The controller is also used to adjust the waveform encoding of the transmitted signal according to the nature and distance of the detected target, the waveform encoding including amplitude and frequency encoding.

4. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 1, characterized in that, The specific manner in which multiple controlled seismic sources are installed at multiple locations within the tunnel includes: Several controlled seismic sources are installed at fixed intervals within the tunnel, either on the tunnel floor or sidewalls, at the tunnel face, at the working face, or on both sides of the mining face. The controlled seismic sources are connected to each other by cable or wireless means and connected to the controller. The controller synchronizes the time between each controlled seismic source through precise time synchronization and timing methods and sends out seismic wave excitation control signals. The time synchronization and timing methods include, but are not limited to, PTP protocol, GPS, atomic clock, and temperature-controlled crystal oscillator. The controller's transmission parameters include: the excitation waveform, initial frequency, initial phase, and start-up time of each controlled vibration source.

5. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 2, characterized in that, The distributed optical cable includes, but is not limited to, distributed fiber optic acoustic sensing devices. The detector array includes, but is not limited to, densely arranged single-component or three-component detector devices. The spatial sampling interval of the distributed optical cable or the detector array is less than or equal to half the wavelength of the emitted directional plane wave. It receives the seismic signals reflected back from the directional plane wave when it encounters geological structures or anomalous properties in the tunnel, mining roadway, or working face or sidewall, to ensure a complete record of the wave field.

6. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 5, characterized in that, The specific manner in which the plurality of receiving devices are installed at the preset location includes: Multiple distributed fiber optic acoustic sensors are laid on the floor, roof, or sidewalls of tunnels or mining roadways, and tightly coupled to the tunnel or mining roadway walls using cement mortar, polymer materials, or gypsum; or, Multiple three-component or single-component geophones are densely fixed to the anchor bolts supporting the tunnel or mining roadway to achieve tight coupling with the tunnel or roadway wall; or, Simultaneously, multiple distributed fiber optic acoustic sensors and multiple three-component detectors are deployed to integrate high-density, multi-component observations from the distributed fiber optic acoustic sensors and the three-component detectors, thereby achieving complete observation of the seismic wavefield.

7. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 1, characterized in that, The data processing terminal acquires the reflected seismic signals and the directional plane waves in real time, and performs preprocessing, including storage, filtering, time-frequency analysis, and noise reduction. The data processing terminal inputs pre-installed seismic detection and imaging software for advanced detection, seismic monitoring, and geological anomaly imaging; The data processing terminal identifies the characteristics of abnormal geological structures from the reflected seismic signals, detects and monitors their presence, locates them, performs inversion imaging, estimates the size, shape, orientation, type, and physical properties of abnormal geological bodies, and outputs the identification, location, and attribute feature inversion imaging results of abnormal geological bodies. As detection and monitoring continue, the detection results of abnormal geological bodies are dynamically corrected and updated, and the development of abnormal geological bodies is monitored as tunnel excavation or mining processes progress, as well as the stability of the surrounding rock during tunnel excavation or mining processes. The types of abnormal geological bodies include, but are not limited to, faults, fracture zones, karst caves, collapse columns, goaf areas, and water-rich areas; The physical properties of the anomalous geological bodies include, but are not limited to, longitudinal and transverse wave velocities, anisotropy, and attenuation coefficients.

8. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 7, characterized in that, The methods for advanced detection at the data processing end include, but are not limited to: forward modeling and analysis of the reflection characteristics of anomalous geological bodies and automatic separation from clutter, identification of reflection power spectrum characteristics, analysis of interferometric characteristics of coherent superposition of multi-angle plane waves, waveform-based adaptive filtering optimization, reflection wave imaging, transmission wave imaging, scattering wave imaging, and full waveform inversion. In the process of conducting advance detection using any method, the directional plane wave and the reflected seismic signal are used for interferometric superposition, waveform recognition, wavelet transform, spectrum matching, energy analysis, phase analysis, travel time extraction, and target structure inversion. Artificial intelligence methods are used to identify and extract the amplitude, phase, and energy characteristics of the reflected seismic signal, as well as the interferometric pattern characteristics generated by two or more directional plane waves illuminating the geological structural anomaly area, in order to determine the size, shape, and multi-scale structure of the geological body.

9. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 7, characterized in that, The methods for seismic monitoring at the data processing end include, but are not limited to: time-delay imaging, coma cross-correlation, phase interferometry, spatiotemporal scanning using directionally transmitted and received seismic waves, or interferometric superposition of two or more directionally transmitted plane waves, and periodically or continuously detecting the location, morphology, wave velocity, and other attribute information of geological anomalies.

10. The active phased array digital seismic detection system for mining and tunnel excavation faces according to claim 1, characterized in that, Multiple controlled seismic sources constitute a seismic source array in the form of a one-dimensional or two-dimensional array. When the source array is constructed in the form of a one-dimensional array, multiple controlled sources are equally spaced along the tunnel extension direction inside the tunnel. The spacing is determined according to the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled sources and the total wiring length are determined by the beamwidth of the directional plane wave. Multiple receiving devices are deployed at equal intervals along the tunnel extension direction inside the tunnel, and are interspersed with multiple controlled seismic sources. The deployment interval and range are determined according to the spatial resolution of the detection and the range to be detected. During the detection process, coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , , by azimuth Take 0 to Mark the directions of the plane waves to be superimposed, where Indicates propagation in a vertically downward direction; The first one-dimensional controlled seismic source, namely Using the controlled source at the location as a reference source, the distance of each controlled source relative to the first one-dimensional controlled source along the undetermined propagation direction is... r i1 for: The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation time of each controlled seismic source τ i1 for: When the source array is constructed in the form of a two-dimensional array, multiple controlled sources are arranged at equal intervals in the tunnel along the tunnel extension direction in the form of regular quadrilateral or equilateral triangular nodes. The arrangement interval is determined according to the local wave velocity, the depth of the anomaly to be detected, and the source frequency. The number of controlled sources and the total wiring length are determined by the beamwidth of the directional plane wave. Multiple receiving devices are deployed at equal intervals along the tunnel extension direction inside the tunnel, and are interspersed with multiple controlled seismic sources. The deployment interval and range are determined according to the spatial resolution of the detection and the range to be detected. During the detection process, using horizontal coordinates Mark the location of each controlled seismic source and receiving device on the survey line, and record the spatial location of each controlled seismic source as... , The horizontal azimuth angle between the x-axis and the spherical coordinate system. and vertical azimuth Mark the directions of the plane waves to be superimposed, where The value range is 0 to ; The value range is 0 to , Indicates propagation in a vertically downward direction; The first two-dimensional controlled seismic source, namely Using the controlled source at the location as a reference source, the distance of each controlled source relative to the first two-dimensional source along the undetermined propagation direction is... r i2 for: The P-wave velocity that needs to be superimposed and propagates near the tunnel wall is denoted as... Then the relative advance excitation times of each controlled seismic source are: In the above formula, τ i2 This indicates the relative advance excitation time of each controlled seismic source.

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