A method and system for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction

Abstract

The present invention discloses a method and system for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction, which relates to the technical field of geological exploration such as geotechnical engineering and mining. The method includes the following steps: arranging a sound wave transmitting device and a sound wave receiving device at measuring points in the mining area; obtaining the positioning data of the sound wave transmitting device and each sound wave receiving device to obtain corresponding spatial coordinate information, the sound wave transmitting device emits a sound wave signal, and the sound wave receiving device receives the sound wave signal after propagating along the rock mass; drawing a cross-sectional energy distribution map between the measuring points where the sound wave transmitting device and each sound wave receiving device are located to obtain a cross-sectional energy distribution map containing spatial coordinate information, identifying the abnormal area to obtain the final boundary information of the hidden karst cave; drawing a three-dimensional spatial distribution map of the mining area; obtaining a three-dimensional stereogram of the hidden karst cave, and calculating the volume size of the hidden karst cave based on the three-dimensional stereogram of the hidden karst cave. The present invention can greatly improve the accuracy of geological exploration in the early stage of mineral resource exploitation.

Description

Technical Field

[0001] The present invention relates to the technical field of geological exploration such as geotechnical engineering and mining, and particularly relates to a method and system for identifying the location of hidden karst caves in mining areas and three-dimensional reconstruction. Background Art

[0002] With the rapid development of China's economy, the investment in infrastructure projects has increased, the demand for resources has expanded, and hidden karst caves in the fields of geotechnical engineering, geology, mining, etc. occur from time to time. Hidden karst caves greatly weaken the strength and bearing capacity of geological bodies, have strong concealment, and more and more safety problems are caused. They are major potential hazards in the fields of geotechnical engineering and mining, which have greatly restricted their development. Therefore, the accurate detection of hidden karst caves is an important link and basic work for the safe exploitation of mineral resources.

[0003] In the prior art, for the geological exploration of mines, geophysical exploration and drilling are mainly combined. For example, although geophysical exploration can detect the cross-sectional position of hidden karst cave bodies, its vibration wave receiving accuracy is not high, and it is greatly affected by the detection environment. It can only preliminarily infer the existence of hidden karst caves in the detection area and cannot form the spatial distribution information of hidden karst caves; drilling can accurately detect the spatial position of hidden karst caves, but it is affected by the control of the drilling grid density and it is difficult to accurately obtain the spatial distribution of the boundaries of hidden karst caves. Both methods have their own advantages, but neither of them can accurately obtain the spatial distribution of hidden karst caves, resulting in problems such as unreasonable exploitation of mineral resources and threats to the safe exploitation of mines.

[0004] Chinese invention patent CN114595497A discloses a method and system for intelligent detection of hidden karst caves. The method includes: obtaining the detection target area of hidden karst caves and its attribute information; pre-detecting hidden karst caves to obtain pre-detection results; detecting hidden karst caves to obtain detection results. However, this invention ignores the most essential characteristics of hidden karst caves, that is, according to the filling state of karst caves, they can be divided into fully filled karst caves, partially filled karst caves and unfilled karst caves. Its detection device, the laser rangefinder, is based on the characteristic that the propagation speed of light is constant, and calculates the distance between the target object and the measuring instrument through the time required for the laser beam to travel from emission to reception. It is mainly applicable to unfilled karst caves, is greatly affected by the light intensity of the measurement environment, and cannot be realized in the detection of fully filled karst caves and partially filled karst caves. The application range has limitations. At the same time, this invention improves the detection accuracy through machine learning and increasing detection points (drilling holes). In the case of a more complex internal structure of karst caves, more detection points (drilling holes) are required, which increases the drilling workload of the detection project, the collection data processing is cumbersome, and the economic pressure is relatively large. Summary of the Invention

[0005] To at least address one of the deficiencies of the prior art and achieve safe and efficient mining in mines, the present invention provides a system and method for identifying the location of hidden karsts in mining areas and three-dimensional reconstruction, which is used to solve the problem of accurately locating hidden karsts in mining areas, can achieve the goals of three-dimensional reconstruction and volume calculation of hidden karsts, can solve the technical problems of accurately detecting hidden karsts in mine safety mining projects, and improve the accuracy of geological exploration work.

[0006] To achieve the object of the present invention, a method for identifying the location of hidden karsts in mining areas and three-dimensional reconstruction provided by the present invention is characterized by including the following steps:

[0007] Step 1: A plurality of boreholes, i.e., a plurality of measurement points, are set in the mining area. An acoustic wave transmitting device is arranged in one of the boreholes, and acoustic wave receiving devices are arranged in the other boreholes.

[0008] Step 2: Obtain the positioning data of the acoustic wave transmitting device and each acoustic wave receiving device to obtain the corresponding spatial coordinate information. The acoustic wave transmitting device emits an acoustic wave signal, and the acoustic wave receiving device receives the acoustic wave signal propagated along the rock mass.

[0009] Step 3: Check each positioning data to the actual detection spatial position, extract the acoustic wave signal, convert the acoustic wave signal into readable energy data, preliminarily draw the cross-sectional energy distribution diagram between the measurement points where the acoustic wave transmitting device and each acoustic wave receiving device are located, and check the spatial coordinate information of the acoustic wave transmitting device and each acoustic wave receiving device to the cross-sectional energy distribution diagram to obtain a cross-sectional energy distribution diagram containing spatial coordinate information.

[0010] Step 4: If there is a situation of hidden karsts between the measurement points where the acoustic wave transmitting device and the acoustic wave receiving device are located, the acoustic wave signal received by the acoustic wave receiving device will be attenuated, forming an abnormal area. Based on the cross-sectional energy distribution diagram containing spatial coordinate information, identify the abnormal area, determine the spatial coordinate information data of the hidden karst near the side of the acoustic wave transmitting device, and label and extract the boundary information of the abnormal area. The boundary information includes point and line information.

[0011] Step 5: Swap the acoustic wave receiving devices that have received the attenuated acoustic wave signal with the acoustic wave transmitting device respectively, and perform detection again to obtain the cross-sectional energy distribution diagram containing spatial coordinate information between the corresponding swapped measurement points, and then determine the spatial coordinate information data of the hidden karst near the side of the original acoustic wave receiving device, and label and extract the boundary information of the abnormal area.

[0012] Step 6: Integrate and superimpose the boundary information of the abnormal areas labeled and extracted in Step 4 and Step 5, and obtain the final boundary information of the hidden karst by adjusting the depth positions of the acoustic wave transmitting device and the acoustic wave receiving device in the borehole.

[0013] Step 7: Based on all the sectional energy distribution diagrams, combined with the spatial coordinate information data of the measuring points, use the interpolation method to draw the three-dimensional spatial distribution diagram of the mining area;

[0014] Step 8: Based on the final boundary information of the concealed karst cave obtained in Step 6, extract the boundary information data of the concealed karst cave. Combine with the three-dimensional spatial distribution diagram of the mining area in Step 7, use the interpolation method to obtain the three-dimensional solid diagram of the concealed karst cave, and calculate the volume of the concealed karst cave based on the three-dimensional solid diagram of the concealed karst cave.

[0015] Preferably, the interpolation method is any one of the Kriging interpolation method and the inverse distance interpolation method.

[0016] The present invention also provides a system for identifying the location of concealed karst caves and three-dimensional reconstruction in a mining area, which is used to implement the foregoing method. The system includes:

[0017] An acoustic wave emission device, which is used to emit acoustic wave signals:

[0018] A plurality of acoustic wave receiving devices, which are used to receive the acoustic wave signals emitted by the acoustic wave emission device:

[0019] A ground control and data acquisition system, which is used to receive and store the acoustic wave signals emitted by the acoustic wave emission device and the acoustic wave signals received by the acoustic wave receiving devices;

[0020] A data processing and plotting system, which is used to preprocess and plot the acoustic wave signals received by the ground control and data acquisition system.

[0021] Preferably, a plurality of boreholes are drilled in the mining area. An acoustic wave emission device is arranged in one of the boreholes, and acoustic wave receiving devices are arranged in the other boreholes.

[0022] Preferably, both the acoustic wave emission device and the acoustic wave receiving device are internally provided with locators, which are used to obtain the positioning data of the acoustic wave emission device and each acoustic wave receiving device.

[0023] Preferably, both the acoustic wave emission device and the acoustic wave receiving device are provided with conical protection structures.

[0024] Preferably, the outer walls of the acoustic wave emission device and the acoustic wave receiving device are fixed to the borehole wall through retractable tripod supports.

[0025] Preferably, the fixing method of the acoustic wave emission device uses 4 retractable tripod supports for fixing, and is remotely controlled through an acoustic wave emission / reception control system. The acoustic wave is transmitted to the borehole wall through the retractable tripod support to reduce the acoustic wave attenuation rate and improve the detection accuracy.

[0026] Preferably, the acoustic wave receiving device is fixed by four retractable tripod supports and remotely controlled by an acoustic wave transmitting / receiving control system. The acoustic wave is transmitted to the acoustic wave receiving device through the retractable tripod supports to improve the acquisition and reception effect of the acoustic wave.

[0027] Preferably, the retractable tripod support includes a tube sleeve, a telescopic tube, a telescopic rod, a leg fixing ring, legs, a support rod, and rotating balls. The tube sleeve is placed inside the acoustic wave transmitting device and the acoustic wave receiving device. The telescopic tube is telescopically arranged in the tube sleeve, and the telescopic rod is telescopically arranged in the telescopic tube. The leg fixing ring is fixed to the telescopic tube, and the legs are fixed to the telescopic tube through the leg fixing ring. The legs are connected to the rotating balls arranged on the telescopic rod through the support rod. The legs can rotate along the extension direction of the telescopic rod, and the legs and the support rod contract and expand with the telescopic movement of the telescopic rod.

[0028] Preferably, the ground control and data acquisition system includes an acoustic wave transmitting / receiving control system. The retractable tripod support is controlled by the acoustic wave transmitting / receiving control system. The acoustic wave transmitting / receiving control system is internally provided with a start 1 button and a reset 1 button for controlling the telescopic movement of the telescopic tube. The start 1 button is for the telescopic tube to extend, and the reset 1 button is for the telescopic tube to contract. It is also internally provided with a start 2 button and a reset 2 button for controlling the telescopic movement of the telescopic rod. The start 2 button is for the telescopic rod to contract and the legs to expand, and the reset 2 button is for the telescopic rod to extend and the legs to fold up. When lowering and lifting the acoustic wave transmitting device and the acoustic wave receiving device, the retractable tripod support is retracted through the control of the acoustic wave transmitting / receiving control system in the ground control and data acquisition system. When determining the installation positions of the acoustic wave transmitting device and the acoustic wave receiving device, the retractable tripod support is extended and unfolded through the control of the acoustic wave transmitting / receiving control system.

[0029] Preferably, the acoustic wave transmitting device is controlled by the ground control and data acquisition system to generate an acoustic wave frequency band; the acoustic wave receiving device is controlled by the ground control and data acquisition system to receive the acoustic wave.

[0030] Preferably, the acoustic wave transmitting device is controlled by the ground control and data acquisition system and can generate acoustic waves in the frequency band of 20 - 20000 Hz; the acoustic wave receiving device is controlled by the ground control and data acquisition system and can receive acoustic waves in the frequency band of 20 - 20000 Hz; the ground control and data acquisition system can control the acoustic wave transmitting device to emit acoustic waves in the frequency band of 20 - 20000 Hz according to the geological rock mass characteristics, adjust the receiving frequency band of the acoustic wave receiving device, and transmit the data collected from the transmitting frequency band and the receiving frequency band to the ground data acquisition system.

[0031] Preferably, after the acoustic wave transmitting device emits an acoustic wave, the acoustic wave propagates along the borehole wall. The acoustic wave receiving device receives the acoustic wave of the borehole, converts the acoustic wave signal into an electrical signal, and transmits it to the ground control system through an optical fiber or a cable for data storage.

[0032] A method and system for identifying the location and three-dimensional reconstruction of hidden karsts in mining areas provided by the present invention have at least the following beneficial effects:

[0033] 1. The present invention emits sound waves in a borehole through a sound wave emitting device, and installs a sound wave receiving device in the borehole. When the sound wave emitting device emits sound waves, the sound wave receiving device can receive the sound waves emitted by the sound wave emitting device. When there is a hidden karst between the sound wave emitting device and the sound wave receiving device, an abnormal attenuation area of the received sound waves will occur in this direction, so as to realize the preliminary detection of the exploration area.

[0034] 2. In the present invention, if an abnormal sound wave area is found in the preliminary exploration, by adjusting the positions of the sound wave emitting device and the receiving device in the borehole, sound wave signal data at different depth levels can be obtained, realizing the collection of sound wave signal data for the entire cross-section, and further accurately detecting the spatial distribution of the hidden karst in this cross-section.

[0035] 3. The present invention can arrange sound wave receiving devices in multiple directions, collect sound wave signal data in multiple directions, obtain a distribution map of karst information for multiple cross-sections, and can systematically process the hidden karst information of multiple cross-sections by using interpolation methods such as Kriging / inverse distance interpolation method, and can obtain the three-dimensional spatial distribution of hidden karsts in the entire detection area.

[0036] 4. The present invention can digitally process the spatial distribution of hidden karsts in the obtained detection area, capture the boundary point, line, and surface information of the hidden karst distribution, accurately identify the spatial form and location of the hidden karst, and through secondary processing to extract boundary information, the volume of the hidden karst can be accurately calculated.

[0037] 5. Through the characteristics of sound wave signal data, the present invention can not only realize the detection of the development of hidden karsts, accurately identify the spatial form and distribution of hidden karsts, but also calculate the volume of hidden karsts, greatly improving the detection accuracy of hidden karsts, preliminarily judging the connectivity between hidden karsts and underground water-bearing bodies and aquifers, and greatly reducing the workload and construction cost of advance exploration during the resource mining process in mines.

[0038] 6. The present invention is applicable to the detection of any type of hidden karst, can improve the accuracy of the detailed geological exploration results in mines, and can also indicate the exploration of bad geological bodies such as fracture zones and faults, providing accurate and reliable preliminary basic data for the safe, efficient, and rational mining of mine resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the structural composition system of each part in the embodiment of the present invention;

[0040] Figure 2(a) is a schematic diagram of the structures of the sound wave emitting device and the sound wave receiving device in the embodiment of the present invention;

[0041] Figure 2(b) is a schematic structural diagram of the retractable tripod in the embodiment of the present invention;

[0042] Figure 3 It is a schematic diagram of the distribution of detection points of the acoustic wave transmitting device and the acoustic wave receiving device in the embodiment of the present invention;

[0043] Figure 4 It is a schematic diagram of detecting concealed karst caves in the embodiment of the present invention;

[0044] Figure 5 It is a flowchart of the data processing and drawing method in the embodiment of the present invention;

[0045] In the figure: 1. Signal and power supply wire; 2. Cone protection structure; 3. Retractable tripod; 3-1. Pipe sleeve; 3-2. Telescopic pipe; 3-3. Telescopic rod; 3-4. Leg fixing ring; 3-5. Leg; 3-6. Support rod; 3-7. Rotating ball; 4. Positioner; 5. Acoustic wave transmitter or receiver; 6. Acoustic wave emission drilling hole; 7. Acoustic wave reception drilling hole; 8. Main control machine; 9. Signal and power supply wire; 10. Drilling hole; 11. Acoustic wave receiving device; 12. Acoustic wave transmitting device; 13. Concealed karst cave. Specific implementation manners

[0046] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] As Figure 1 shown, a system for identifying the position and three-dimensional reconstruction of concealed karst caves in a mining area provided by the present invention includes an acoustic wave transmitting device 12, an acoustic wave receiving device 11, a ground control and data acquisition system, and a data processing and drawing system. The ground control and data acquisition system includes an acoustic wave transmitting / receiving control system, a GPS positioning system, and a data acquisition system. The acoustic wave transmitting / receiving control system, the GPS positioning system, and the data acquisition system are integrated in a main control machine (control platform). The data acquisition system receives and stores the acoustic wave signals transmitted by the acoustic wave transmitting device 12 and the acoustic wave signals received by the acoustic wave receiving device 11.

[0048] A plurality of drilling holes are opened in the mining area. An acoustic wave transmitting device 12 is arranged in one of the drilling holes, and acoustic wave receiving devices 11 are arranged in other drilling holes surrounding the drilling hole.

[0049] The acoustic wave emission device 12 is controlled by the acoustic wave emission / reception control system in the ground control and data acquisition system, and can generate acoustic waves of different frequency bands, such as acoustic waves in the range of 20 to 20000 Hz. After the acoustic wave emission device 11 emits acoustic waves, the acoustic waves propagate along the borehole wall. The acoustic wave reception device 11 receives the acoustic wave information, converts the acoustic wave signal into an electrical signal, and transmits it to the ground control and data acquisition system through an optical fiber or a cable for data storage. The acoustic wave reception device 11 can receive the acoustic wave frequency band and is controlled by the acoustic wave emission / reception control system in the ground control and data acquisition system.

[0050] The acoustic wave emission device 12 is activated by the acoustic wave emission / reception control system to generate a signal. The acoustic wave signal is transmitted to the geological rock mass. After the acoustic wave reception device 11 receives the acoustic wave signal, it is transmitted to the ground control and data acquisition system. When there is a development of a hidden karst cave in the transmission path of the acoustic wave signal, the acoustic wave signal received in the direction of this path will be significantly attenuated, and a signal abnormal area will appear, thus enabling the preliminary detection of the hidden karst cave in the detection area. By adjusting the different orientations and depths of the acoustic wave emission device 12 and the acoustic wave reception device 11, the precise detection of the spatial distribution of the hidden karst cave can be achieved.

[0051] The ground control and data acquisition system is used to control the acoustic wave emission device 12 to emit different frequency bands according to the characteristics of the geological rock mass through the acoustic wave emission / reception control system, adjust the reception frequency band of the acoustic wave reception device 11, and transmit the collected data of the emission frequency band and the reception frequency band to the data acquisition system in the ground control and data acquisition system. Through the data acquisition system, the collected acoustic wave data is stored and converted into an electrical signal.

[0052] Both the acoustic wave transmitting device 12 and the acoustic wave receiving device 11 are fixed on the borehole wall through the retractable tripod 3. The ground control and data acquisition system can control the retractable tripod to fix the acoustic wave transmitting device / the acoustic wave receiving device. In some embodiments of the present invention, the acoustic wave transmitting device 12 and the acoustic wave receiving device 11 are fixed to the sidewall of the borehole by using 4 retractable tripods 3 according to the detection requirements. The acoustic wave transmitting device 12 is activated to generate a signal through the acoustic wave transmitting / receiving control system, and the acoustic wave signal can be transmitted to the geological rock mass through the retractable tripod to reduce the energy attenuation caused by air propagation. Referring to Fig. 2(b), the retractable tripod 3 includes a sleeve 3-1, a telescopic tube 3-2, a telescopic rod 3-3, a foot fixing ring 3-4, a foot 3-5, a support rod 3-6 and a rotating ball 3-7. The sleeve 3-1 is built into the acoustic wave transmitting device 12 and the acoustic wave receiving device 11. The telescopic tube 3-2 is telescopically arranged in the sleeve 3-1. The telescopic rod 3-3 is telescopically arranged in the telescopic tube 3-2. The foot fixing ring 3-4 is fixed on the telescopic tube 3-2. The foot 3-5 is fixed on the telescopic tube 3-2 through the foot fixing ring 3-4, and the foot 3-5 is connected to the rotating ball 3-7 arranged on the telescopic rod 3-3 through the support rod 3-6. The foot 3-5 can rotate along the extending direction of the telescopic rod 3-3. The foot 3-5 and the support rod 3-6 contract and expand due to the telescopic movement of the telescopic rod 3-3.

[0053] The retractable tripod 3 is controlled by the acoustic wave transmitting / receiving control system. In the acoustic wave transmitting / receiving control system, there are a start 1 button and a reset 1 button for controlling the telescopic movement of the telescopic tube 3-2. The start 1 button is for the telescopic tube 3-2 to extend, and the reset 1 button is for the telescopic tube 3-2 to contract. And there are a start 2 button and a reset 2 button for controlling the telescopic movement of the telescopic rod 3-3. The start 2 button is for the telescopic rod 3-3 to contract and the feet to expand, and the reset 2 button is for the telescopic rod 3-3 to extend and the feet to fold up. The acoustic wave receiving device 11 is controlled by the acoustic wave transmitting / receiving control system in the ground control and data acquisition system. Through the acoustic wave transmitting / receiving control system, the retractable tripod 3 can be controlled so that the acoustic wave transmitting device 12 is fixed on the borehole wall through the retractable tripod 3, preventing the swinging of the acoustic wave transmitting device 2 from affecting the instability of receiving acoustic wave signals.

[0054] When the acoustic wave transmitting device 12 and the acoustic wave receiving device 11 are lowered and lifted, the retractable tripod 3 is retracted through the reset buttons (first the reset 2 button and then the reset 1 button) built into the acoustic wave transmitting / receiving control system. When determining the installation positions of the acoustic wave transmitting device 12 and the acoustic wave receiving device 11, the retractable tripod 3 is extended through the start buttons (first the start 1 button and then the start 2 button) built into the acoustic wave transmitting / receiving control system. After the retractable tripod 3 is extended, the acoustic wave transmitting device 12 and the acoustic wave receiving device 11 can be fixed on the borehole wall by supporting on the borehole wall through the feet 3-5.

[0055] The extension of the retractable tripod 3 controlled by the acoustic wave transmitting / receiving control system can fix the acoustic wave transmitting device 12 and the acoustic wave transmitting device 12 to the borehole wall, preventing the instability of the excitation signal caused by the swing of the acoustic wave transmitting device 12.

[0056] Existing products are used for the ground control and data acquisition system, data processing and plotting system, main control system, etc., and will not be elaborated here.

[0057] In some embodiments of the present invention, the acoustic wave transmitting device 12 includes a transmitting body and an acoustic wave transmitter disposed in the transmitting body, the acoustic wave receiving device 11 includes a receiving body and an acoustic wave receiver disposed in the receiving body, and positioners are provided in both the transmitting body and the receiving body. The spatial coordinates of the acoustic wave transmitting device and the acoustic wave receiving device are collected by the built-in positioners and transmitted to the ground control and data acquisition system. Cone protection structures 2 are provided at both ends of the transmitting body and the transmitting body.

[0058] The cone protection structure 2 can, on the one hand, facilitate the lowering and lifting of the device along the borehole, and on the other hand, prevent the falling of borehole debris and damage the internal transmitter and receiver.

[0059] The data processing and plotting system converts, processes the data collected by the ground control and data acquisition system, and performs visual plotting. Specifically, the data processing and plotting system can convert the data format of the electrical signals in the ground control and data acquisition system, and combine with the spatial coordinate information collected by the positioners of the acoustic wave transmitting device and the acoustic wave receiving device to draw an energy distribution map.

[0060] In some embodiments of the present invention, a method for identifying the position of hidden karst caves in a mining area and three-dimensional reconstruction is also provided, which is implemented by using the system provided in the foregoing embodiments. The method includes the following steps:

[0061] Step 1: A plurality of boreholes, i.e., a plurality of measuring points, are arranged in the mining area. An acoustic wave transmitting device 12 is arranged in one borehole, and acoustic wave receiving devices 11 are arranged in other boreholes.

[0062] In this step, according to different refinement degrees, the measuring point arrangement can be selected as 5-point type, 7-point type, 9-point type, etc. One borehole is one measuring point, and the measuring point arrangement reference Figure 3 , can be arranged in a 5-point type, that is, 4 acoustic wave receiving devices 11 are arranged around the acoustic wave transmitting device 12, can be arranged in a 7-point type, that is, 6 acoustic wave receiving devices 11 are arranged around the acoustic wave transmitting device 12, can be arranged in a 9-point type, that is, 8 acoustic wave receiving devices 11 are arranged around the acoustic wave transmitting device 12. In other embodiments, it can also be set in other arrangement ways according to needs.

[0063] Step 2: Obtain the positioning data of the acoustic wave emission device 12 and each acoustic wave receiving device 11 to obtain the corresponding spatial coordinate information. The acoustic wave emission device 12 emits an acoustic wave signal, and the acoustic wave receiving device 11 receives the acoustic wave signal after propagation along the rock mass. The data acquisition system receives and stores the acoustic wave signal emitted by the acoustic wave emission device 12 and also receives and stores the acoustic wave signal received by the acoustic wave receiving device 11.

[0064] Step 3: The data processing and plotting system checks the positioning data to the actual detection spatial position, extracts the acoustic wave signals, converts the acoustic wave signals into readable energy data, preliminarily plots the cross-sectional energy distribution map between the measuring points where the acoustic wave emission device and each acoustic wave receiving device are located, and checks the spatial coordinate information (obtained by the GPS satellite positioning system) of the acoustic wave emission device 12 and each acoustic wave receiving device 11 to the cross-sectional energy distribution map, and plots the cross-sectional energy distribution map containing the spatial coordinate information.

[0065] In this step, data processing is performed on the acoustic wave signals collected between all measuring points. The data processing includes filtering, noise reduction, gain, and data format conversion to obtain the cross-sectional energy distribution map between the measuring points.

[0066] Step 4: Identify the abnormal area based on the cross-sectional energy distribution map containing the spatial coordinate information, determine the spatial coordinate information data of the concealed karst cave on the side close to the acoustic wave emission device 12, and label and extract the boundary information of the abnormal area. The boundary information includes point and line information.

[0067] Step 5: Swap the acoustic wave receiving devices 11 corresponding to the abnormal area, that is, the acoustic wave receiving devices 11 where the received acoustic wave signals have attenuated, with the acoustic wave emission device 12 respectively, and perform detection again to obtain the cross-sectional energy distribution map containing the spatial coordinate information after the corresponding measuring points are swapped, and then determine the spatial coordinate information data of the concealed karst cave on the side close to the original acoustic wave receiving device 11, and label and extract the boundary information of the abnormal area.

[0068] In this step, by swapping the measuring points, the measuring points of the original acoustic wave emission device 12 are replaced with the measuring points of the acoustic wave receiving device 11, and the measuring points of the original acoustic wave receiving device 11 are replaced with the measuring points of the acoustic wave emission device 12, and detection is performed again, so as to obtain the accurate boundary information of the concealed karst cave and improve the accuracy of identification.

[0069] Step 6: Integrate and superimpose the boundary information of the abnormal area labeled and extracted in Step 4 and Step 5, and obtain the final boundary information of the concealed karst cave by adjusting the depth positions of the acoustic wave emission device 12 and the acoustic wave receiving device 11 in the borehole.

[0070] Step 7: Based on all the sectional energy distribution maps, combined with the GPS spatial coordinate information data of the measuring points, use Kriging and inverse distance interpolation methods to draw a three-dimensional spatial distribution map of the mining area.

[0071] Step 8: Based on the final boundary information of the concealed karst cave obtained in Step 6, extract the boundary information data of the concealed karst cave, use Kriging and inverse distance interpolation methods, combined with the three-dimensional spatial distribution map of the mining area in Step 7, to obtain a three-dimensional map of the concealed karst cave, and calculate the volume of the concealed karst cave based on the three-dimensional map of the concealed karst cave.

[0072] The data processing and mapping system is configured to perform the following operations:

[0073] Data preprocessing: Through the positioning data measured by the locators built in the acoustic emission device 12 and the acoustic receiving device 11, the measurement results (i.e., spatial coordinate information) of the measuring points of each acoustic emission device 12 and acoustic receiving device 11 are calibrated to the actual detection spatial position.

[0074] Attribute setting: According to the positioning results of each measuring point, the geological conditions of the detection area (mining area) and the propagation law of sound waves, perform attribute settings (including geological attribute parameters, filtering parameters, noise reduction parameters, etc.) in the data processing and mapping system, and perform data preprocessing to achieve the effects of filtering, noise reduction, and gain of the positioning results.

[0075] Data format conversion and mapping: After attribute setting, extract the acoustic signals collected by the data acquisition system, convert the acoustic signals into readable energy data, preliminarily draw the sectional energy distribution map between the measuring points where the wave emission device and each acoustic receiving device are located, integrate and process with the GPS satellite positioning data, and calibrate the spatial coordinate information (obtained by the GPS satellite positioning system) of each acoustic emission device 12 and acoustic receiving device 11 to the sectional energy distribution map, and draw the sectional energy distribution map including spatial coordinates.

[0076] Spatial distribution: If there is a hidden karst cave between the acoustic wave emission device 12 and the acoustic wave reception device 11, the acoustic wave signals received by the acoustic wave reception device 11 will be significantly attenuated, forming an abnormal area. Then, based on the cross-sectional energy distribution map containing spatial coordinates drawn, the abnormal area (hidden karst cave) can be identified, and the spatial coordinate information data of the hidden karst cave on the side close to the acoustic wave emission device 12 can be determined. The boundary information of the abnormal area is marked and extracted, and the boundary information includes point and line information. To avoid the influence of the hidden karst cave on the signals collected by the acoustic wave reception device 11, when there is an abnormal area in the cross-sectional energy distribution map drawn from the data collected by the acoustic wave reception device 11, the measuring point of the original acoustic wave emission device 12 is replaced with the measuring point of the acoustic wave reception device 11, and the measuring point of the original acoustic wave reception device 11 is replaced with the measuring point of the acoustic wave emission device 12, and then the detection is carried out again to determine the spatial coordinate information data of the hidden karst cave on the side close to the original acoustic wave reception device 11, and the boundary information (point and line information) of the abnormal area is marked and extracted. Further, the boundary information of the abnormal area marked and extracted before and after the swapping is subjected to superposition processing. The cross-sectional energy distribution maps between all measuring points are obtained, and combined with the GPS spatial coordinate information data of all measuring points, any interpolation method such as Kriging and inverse distance interpolation method is used to draw the three-dimensional spatial stereo distribution map of the hidden karst caves in the detection area. According to the marking situation of the boundary information of the hidden karst cave, the precise spatial stereo distribution situation of the hidden karst cave is obtained, the extracted boundary information of the abnormal area is processed, and any interpolation method such as Kriging and inverse distance interpolation method is used to calculate the volume size of the hidden karst cave.

[0077] The present invention can collect the acoustic wave frequency bands of karst caves and rock masses, set up acoustic wave emission and reception equipment at fixed points in the area to be surveyed, set the acoustic wave emission frequency, and identify whether there is a karst cave through the received frequency of the acoustic wave. If there is, then adjust the positions of the acoustic wave emission / reception devices in the drilling depth direction, swap the distribution of the acoustic wave emission device and the acoustic wave reception device, and the acoustic wave frequency band. Combining the positioners of the acoustic wave emission device and the acoustic wave reception device, the spatial form and distribution situation of the hidden karst cave can be accurately identified. By summarizing the emission / reception frequency band distribution maps of the frequency bands, the spatial distribution situation of the karst caves in the mining area can be drawn, and further the volume size of the hidden karst cave can be calculated. The present invention can greatly improve the accuracy of geological exploration in the early stage of mineral resource exploitation, effectively avoid safety disaster accidents caused by hidden karst caves during the mineral resource exploitation process, reduce the frequency of safety accidents in resource exploitation, and effectively optimize the reasonable exploitation of resources.

[0078] In the description of the present invention, it should be noted that the terms involved are only for facilitating the description of the present invention and simplifying the description. The hidden karst cave belongs to a kind of bad geological body, so it cannot be understood as a limitation to the present invention.

[0079] Although embodiments of the present invention have been shown and described, the embodiments of the present invention are not limited by the above examples. Any changes, modifications, substitutions, simplifications, and variations made without departing from the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction, characterized in that, It includes the following steps: Step 1: A plurality of boreholes, i.e., a plurality of measuring points, are arranged in the mining area. An acoustic wave transmitting device is arranged in one borehole, and acoustic wave receiving devices are arranged in other boreholes. Step 2: Obtain the positioning data of the acoustic wave transmitting device and each acoustic wave receiving device to obtain the corresponding spatial coordinate information. The acoustic wave transmitting device emits an acoustic wave signal, and the acoustic wave receiving device receives the acoustic wave signal after propagation along the rock mass. Step 3: Check each positioning data to the actual detection spatial position, extract the acoustic wave signal, convert the acoustic wave signal into readable energy data, preliminarily draw the sectional energy distribution diagram between the measuring points where the acoustic wave transmitting device and each acoustic wave receiving device are located, and check the spatial coordinate information of the acoustic wave transmitting device and each acoustic wave receiving device to the sectional energy distribution diagram to obtain the sectional energy distribution diagram containing spatial coordinate information. Step 4: If there is a concealed karst cave between the measuring points where the acoustic wave transmitting device and the acoustic wave receiving device are located, the acoustic wave signal received by the acoustic wave receiving device will be attenuated, forming an abnormal area. Based on the sectional energy distribution diagram containing spatial coordinate information, identify the abnormal area, determine the spatial coordinate information data of the concealed karst cave on the side close to the acoustic wave transmitting device, and mark and extract the boundary information of the abnormal area. The boundary information includes point and line information. Step 5: Swap the acoustic wave receiving devices whose received acoustic wave signals have been attenuated with the acoustic wave transmitting device respectively, and perform detection again to obtain the sectional energy distribution diagram containing spatial coordinate information between the swapped measuring points, and then determine the spatial coordinate information data of the concealed karst cave on the side close to the original acoustic wave receiving device, and mark and extract the boundary information of the abnormal area. Step 6: Integrate and superimpose the boundary information of the abnormal areas marked and extracted in Step 4 and Step 5, and obtain the final boundary information of the concealed karst cave by adjusting the depth positions of the acoustic wave transmitting device and the acoustic wave receiving device in the borehole. Step 7: Based on all the sectional energy distribution diagrams, combined with the spatial coordinate information data of the measuring points, use the interpolation method to draw the three-dimensional spatial stereo distribution diagram of the mining area. Step 8: Based on the final boundary information of the concealed karst cave obtained in Step 6, extract the boundary information data of the concealed karst cave, combined with the three-dimensional spatial stereo distribution diagram of the mining area in Step 7, use the interpolation method to obtain the three-dimensional stereo diagram of the concealed karst cave, and calculate the volume size of the concealed karst cave based on the three-dimensional stereo diagram of the concealed karst cave.

2. The method for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction according to claim 1, wherein The interpolation method is any one of the Kriging interpolation method and the inverse distance interpolation method.

3. A system for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction, characterized in that, For implementing the method according to any one of claims 1-2, the system includes: An acoustic wave transmitting device for emitting an acoustic wave signal: A plurality of acoustic wave receiving devices for receiving the acoustic wave signal emitted by the acoustic wave transmitting device: A ground control and data acquisition system for receiving and storing the acoustic wave signal emitted by the acoustic wave transmitting device and the acoustic wave signal received by the acoustic wave receiving device; A data processing and drawing system for preprocessing and drawing the acoustic wave signal received by the ground control and data acquisition system.

4. The position identification and three-dimensional reconstruction system for concealed karst caves in a mining area according to claim 3, characterized in that, A plurality of boreholes are drilled in the mining area. An acoustic wave transmitting device is arranged in one borehole, and acoustic wave receiving devices are arranged in other boreholes.

5. The location recognition and three-dimensional reconstruction system for concealed karst caves in a mining area according to claim 3, characterized in that, Both the acoustic wave transmitting device and the acoustic wave receiving device are internally equipped with locators for obtaining the positioning data of the acoustic wave transmitting device and each acoustic wave receiving device.

6. The system for identifying the position of hidden karst caves in a mining area and three-dimensional reconstruction according to claim 3, characterized in that, Both the acoustic wave transmitting device and the acoustic wave receiving device are provided with conical protective structures.

7. The location recognition and three-dimensional reconstruction system for concealed karst caves in a mining area according to claim 4, characterized in that The outer walls of the acoustic wave transmitting device and the acoustic wave receiving device are fixed to the drilling wall through retractable tripod supports.

8. A system for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction according to claim 7, characterized in that, The retractable tripod support includes a pipe sleeve, a telescopic pipe, a telescopic rod, a leg fixing ring, legs, a support rod, and rotating balls. The pipe sleeve is built into the acoustic wave transmitting device and the acoustic wave receiving device. The telescopic pipe is telescopically arranged in the pipe sleeve. The telescopic rod is telescopically arranged in the telescopic pipe. The leg fixing ring is fixed to the telescopic pipe. The legs are fixed to the telescopic pipe through the leg fixing ring. And the legs are connected to the rotating balls arranged on the telescopic rod through the support rod. The legs can rotate along the extending direction of the telescopic rod. The legs and the support rod contract and expand with the telescopic movement of the telescopic rod.

9. The system for identifying the position of hidden karst caves in a mining area and three-dimensional reconstruction according to claim 8, characterized in that, The ground control and data acquisition system includes an acoustic wave transmitting / receiving control system. The retractable tripod support is controlled by the acoustic wave transmitting / receiving control system. The acoustic wave transmitting / receiving control system is internally equipped with a start 1 button and a reset 1 button for controlling the telescopic movement of the telescopic pipe. The start 1 button is for the telescopic pipe to extend, and the reset 1 button is for the telescopic pipe to contract. And it is internally equipped with a start 2 button and a reset 2 button for controlling the telescopic movement of the telescopic rod. The start 2 button is for the telescopic rod to contract and the legs to expand, and the reset 2 button is for the telescopic rod to extend and the legs to fold up.

10. A system for identifying the location of hidden karst caves in a mining area and three-dimensional reconstruction according to any one of claims 3-9, characterized in that, The acoustic wave transmitting device is controlled by the ground control and data acquisition system to generate acoustic wave frequencies. The acoustic wave receiving device is controlled by the ground control and data acquisition system to receive acoustic waves.

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