Tunneling advance geology forecasting method, device, medium and terminal

Abstract

The invention relates to a tunnel tunneling advanced geology forecasting method, which comprises the following steps of: randomly selecting a cross section behind a tunnel face, arranging a measuring point in each of four directions on a tunnel rock wall, performing differential measurement between a central measuring point of the tunnel face and any measuring point on the tunnel rock wall, and taking the direction of the maximum signal difference in four groups of obtained electromagnetic response signal differences as a background direction; respectively obtaining electromagnetic response signal differences of the other three azimuth measuring points of the tunnel rock wall and the central measuring point of the tunnel face relative to the background azimuth measuring point according to the measurement results, comparing the four electromagnetic response signal differences, and selecting the response signal difference with the maximum absolute amplitude and the slowest amplitude attenuation along with time; and interpreting the orientation and distribution characteristics of the water-containing or ore-containing abnormal geology. According to the method, a double-differential measurement mode is adopted, primary field interference generated by a transmitting-receiving coil can be overcome, response background interference generated by surrounding rock can be eliminated, obtained response signal difference data has the extremely high signal-to-noise ratio, the higher resolution ratio is achieved for geological hidden dangers, and the detection result is more accurate and reliable.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering measurement, and discloses a method, equipment, medium and terminal for advanced geological prediction of tunnel excavation. Background Art

[0002] In underground engineering construction or mining operations, there are often engineering geological hazards such as water storage structures and broken zones in the tunnel working face or stop / head and the surrounding areas. Compared with advance drilling methods, advance geological prediction is a fast and economical geophysical prospecting technology to identify engineering geological hazards. It is widely welcomed by production units, but to improve its detection accuracy, it is necessary to adapt to local conditions and adopt scientific technical methods. Compared with technical methods such as seismic advance geological prediction and electrical advance geological prediction, electromagnetic advance prediction uses electromagnetic induction. Electromagnetic induction coils or sensors do not require additional construction to be placed in the surrounding rock mass, and the detection operation efficiency is higher.

[0003] However, many practices have shown that the working environment of electromagnetic advanced geological prediction is quite complex. It not only faces the electromagnetic response interference of various metal components, but also faces the background electrical change interference caused by the complex and unknown geological conditions of the surrounding rock. The former can be overcome to a certain extent during construction, but the latter is difficult to predict and is a major problem to be solved in advanced geological exploration. The different types or existence states of the surrounding rock media often lead to large changes in their electrical parameters. If the normal surrounding rock electromagnetic response background cannot be accurately extracted and the surrounding rock response and hidden danger abnormal response cannot be distinguished, the reliability of the advanced geological exploration results or the resolution of hidden danger anomalies will be greatly reduced. Therefore, it is urgent to propose an advanced geological prediction method that can accurately identify abnormal geological hazards. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method, equipment, medium and terminal for advanced geological prediction of tunnel excavation to solve the problems of difficulty in distinguishing between normal surrounding rock response and abnormal response of hidden dangers, and insufficient accuracy of detection results.

[0005] To achieve the above object, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for advanced geological prediction of tunnel excavation, comprising the following steps: Arrange one measuring point at the center of the tunnel face; A cross section parallel to the tunnel face is selected behind the tunnel face, and one measuring point is arranged in each of the four directions, namely, the left side, the top, the right side, and the bottom of the tunnel rock wall on the cross section; The electromagnetic method is used to perform differential measurement between the measuring point at the center of the tunnel face and any measuring point on the tunnel rock wall, and the electromagnetic response signal difference between the measuring point at the center of the tunnel face and each measuring point on the tunnel rock wall is obtained. The tunnel rock wall orientation where the maximum electromagnetic response signal difference R0 is located is marked as the background orientation. Calculate the electromagnetic response signal difference Ri of the other three azimuth measuring points of the tunnel rock wall relative to the background azimuth measuring point, i=1, 2, 3; select the electromagnetic response signal difference with the largest absolute amplitude and the slowest amplitude decay over time from Ri and R0, and use the electromagnetic response interpretation algorithm to interpret the location and distribution characteristics of the abnormal geology. The larger the absolute amplitude or the slower the amplitude decays over time, the more serious the abnormal geology in the corresponding direction is predicted.

[0006] Furthermore, the electromagnetic method is one of the transient electromagnetic method, the frequency depth sounding electromagnetic method with variable frequency or frequency combination, and the geological radar method.

[0007] Furthermore, when the electromagnetic method is used for differential measurement, a set of integrated transceiver electromagnetic coils are installed at each of the two measuring points; in the two sets of transceiver electromagnetic coils, the transmitting coil is connected to the transmitting end of the electromagnetic detector in series or in parallel, and the receiving coil is connected to the receiving end of the electromagnetic detector in series or in parallel.

[0008] Furthermore, the transceiver mode of the two sets of transceiver integrated electromagnetic coils is one of one transmit and one receive, one transmit and two receive, two transmit and one receive, and two transmit and two receive.

[0009] Furthermore, in the transceiver integrated electromagnetic coil, the transmitting coil or the receiving coil adopts a magnetic rod with a built-in soft magnetic core or a Hall sensor; or, the transmitting coil is a power supply electrode and the receiving coil is a receiving electrode.

[0010] Furthermore, the electromagnetic response interpretation algorithm adopts one of the following methods: one-dimensional electromagnetic inversion method, two-dimensional electromagnetic inversion method, three-dimensional electromagnetic inversion method, early apparent resistivity conversion algorithm, late apparent resistivity conversion algorithm, power spectrum anomaly analysis method, and entropy spectrum anomaly analysis method.

[0011] Furthermore, when it is predicted that there is abnormal geology ahead of the measuring point at the center of the tunnel face, the direction of the abnormal geology ahead of the measuring point at the center of the tunnel face is further predicted by the following method: Taking the measuring point at the center of the face as the reference, one measuring point is set up in each of the four directions of the top, bottom, left and right of the face. The electromagnetic method is used to perform differential measurement between any measuring point at any direction of the face and the measuring point at the background direction, and the electromagnetic response signal difference between each measuring point at any direction of the face and the measuring point at the background direction is obtained. The response signal difference with the largest absolute amplitude and the slowest amplitude decay over time is selected, and the electromagnetic response interpretation algorithm is used to interpret the location and distribution characteristics of the abnormal geology. The larger the absolute amplitude or the slower the amplitude decays over time, the more serious the abnormal geology in the corresponding direction is predicted.

[0012] In a second aspect, the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the method for advanced geological prediction of tunnel excavation.

[0013] In a third aspect, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the method for advanced geological prediction of tunnel excavation.

[0014] In a fourth aspect, the present invention provides an information data processing terminal, which is used to implement the method for advanced geological prediction of tunnel excavation.

[0015] The technical principle of the present invention is: relative to normal rock and soil media, engineering geological hazards including water storage structures, broken zones, etc. and metal mineral resources generally have lower resistivity, and will form electromagnetic induction (eddy current effect) in the alternating electromagnetic field, thereby hindering the change of the excitation electromagnetic field (primary field), that is, the existence of water-rich engineering geological hazards and metal mineral resources will reduce the speed of change of the excitation electromagnetic field that increases or decreases with time. Typically, during transient electromagnetic measurement, the existence of low-resistivity geological hazards or minerals will cause the secondary field to not decay to zero immediately after the primary field is turned off, and not only will there be a strong response amplitude, but also a slow signal time decay. The lower the resistivity of the geological hazard or mineral or the larger the volume, the greater the abnormal response amplitude, the slower the decay process or the longer the time it takes to decay to zero; When electromagnetic detection is actually used in underground tunnels, there is mutual inductance due to the proximity of the transceiver coils. Even if there is no good conductive geological body, there will be a strong mutual inductance electromagnetic signal in the receiving coil, which will seriously interfere with or even cover the response of the good conductive geological body, thereby reducing the resolution of the good conductive geological body. The present invention eliminates the mutual inductance interference of the transceiver coils at the analog signal level by reverse series connection or parallel subtraction of signals through a pair of transceiver coils with consistent specifications; in addition, hidden geological bodies exist inside the surrounding rock, and the background response interference caused by the surrounding rock geological conditions is another major problem to be solved in geological detection. Effectively eliminating the normal surrounding rock electromagnetic response background will greatly improve the reliability of the obtained abnormal detection results, and the present invention uses the response signal difference of the four directions of the tunnel face relative to the tunnel or the four directions including the tunnel face relative to the background direction to perform abnormal analysis, and also eliminates the response background interference caused by the surrounding rock geological conditions at the analog signal level; as mentioned above, double differential measurement improves the signal-to-noise ratio of the abnormal signal and the quality of the detection data, so that the accuracy and resolution of the detection results are improved.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: 1) A pair of integrated transceiver electromagnetic coils combined with electromagnetic detection instruments are used for differential detection. The primary field response signals of the two sets of receiving coils are directly offset, which first eliminates the interference of the mutual inductance of the transceiver coils. Secondly, the two sets of transceiver electromagnetic coils are attached to the surface of the surrounding rock. The differential measurement process further eliminates the response background interference generated by the surrounding rock itself. Double differential or differential measurement is achieved in one operation, and the signal-to-noise ratio of abnormal signals is higher. The combination of the two differential modes improves the quality of detection data and provides a guarantee for hidden danger judgment and analysis.

[0017] 2) The operating mode of confirming the background first and then the relative abnormality is adopted, which greatly improves the detection results and abnormality resolution capabilities.

[0018] 3) The construction operation is convenient and can adapt to various complex working conditions.

[0019] 4) A single detection operation can not only realize advanced geological prediction in front of the tunnel face, but also detect hidden dangers in the surrounding rock, killing two birds with one stone. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flowchart of the advanced geological prediction method for tunnel excavation.

[0021] Figure 2 The present invention is a schematic diagram of the operation of the advanced geological prediction method for tunnel excavation; in the figure, R palm represents the center measuring point of the tunnel face; R left, R right, R top and R bottom respectively represent the measuring points at the left, right, top and bottom positions of a certain cross section behind the tunnel face corresponding to the tunnel rock wall.

[0022] Figure 3 The figure is a schematic diagram of the detailed detection of hidden dangers on the tunnel face of the advanced geological prediction method of the present invention; in the figure, Rpalm up, Rpalm down, Rpalm left, and Rpalm right respectively represent the measuring points at the four directions of up, down, left, and right in the tunnel face; Rb represents the background direction measuring point.

[0023] Figure 4 It is the electromagnetic response signal difference data of the center measuring point of the tunnel face relative to the four azimuth measuring points on the tunnel rock wall in Example 1.

[0024] Figure 5 It is the electromagnetic response signal difference data of the three azimuth measuring points on the tunnel rock wall and the center measuring point of the tunnel face relative to the background azimuth measuring point in Example 1.

[0025] Figure 6 This is the apparent resistivity profile in Example 1. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0027] Example 1

[0028] This embodiment is an advance geological prediction of hidden floods ahead of a certain traffic tunnel excavation face.

[0029] See also Figure 1 to Figure 6 There may be hidden floods ahead of the tunnel face during construction, which requires advance forecasting. Transient electromagnetic method and transient electromagnetic measuring instrument are selected for advanced geological forecasting and detection.

[0030] The present invention provides a method for advanced geological prediction of tunnel excavation, comprising the following steps: Arrange one measuring point at the center of the tunnel face; A cross section parallel to the tunnel face is selected behind the tunnel face, and one measuring point is arranged in each of the four directions, namely, the left side, top, right side, and bottom side, of the tunnel rock wall on the cross section, to form four directions, namely, the upper, lower, left, and right directions, relative to the measuring point at the center of the tunnel face; The electromagnetic method is used to perform differential measurement between the measuring point at the center of the tunnel face and any measuring point on the tunnel rock wall, and the electromagnetic response signal difference between the measuring point at the center of the tunnel face and each measuring point on the tunnel rock wall is obtained. The direction where the maximum electromagnetic response signal difference R0 is located is marked as the tunnel rock wall background direction. The electromagnetic response signal differences Ri of the other three azimuth measuring points on the tunnel rock wall relative to the background azimuth measuring point are calculated respectively, where i=1, 2, and 3. The electromagnetic response signal difference with the largest absolute amplitude and the slowest amplitude decay over time is selected from Ri and R0, and the electromagnetic response interpretation algorithm is used to interpret the azimuth and distribution characteristics of the abnormal geology.

[0031] Based on the difference between the electromagnetic response signals with the largest absolute amplitude and the amplitude with the slowest decay over time, one or two directions can be obtained, which corresponds to a certain tunnel rock wall measuring point or face measuring point. The direction of the abnormal geology refers to the direction (one or two) of the abnormal geology finally determined based on the difference between the one or two electromagnetic response signals obtained. The distribution characteristics refer to the depth range and low-resistance hidden danger characteristics of the abnormal geology at this direction.

[0032] Specifically, first, stand facing the tunnel face and select a cross section parallel to the tunnel face. The distance between the measuring point section and the tunnel face is 0-10m. Taking the center of the measuring point section as the reference, construct four directions on the rock wall around the tunnel: left, top, right, and bottom. Set one measuring point in each direction to form four directions relative to the tunnel face: top, bottom, left, and right. Figure 2 It should be noted that Figure 2 The middle tunnel face has a rectangular cross section, but the rectangular cross section is only for reference, to show the four directions, and does not represent the actual tunnel cross section.

[0033] Then, take a pair of transceiver-integrated electromagnetic induction coils with consistent electromagnetic response physical properties. One set of transceiver electromagnetic coils is placed at the center measurement point of the heading face, and the other set of transceiver-integrated electromagnetic coils is prepared to move and measure successively along the surrounding rock walls of the tunnel at the measurement points in the left, top, right, and bottom directions. In the two sets of transceiver-integrated electromagnetic coils, the transmitting coil and the receiving coil are connected in series in one forward direction and in series in the opposite direction at the same time, and then are respectively connected to the corresponding receiving end and transmitting end of the electromagnetic method detector to form a differential measurement mode; the transceiver-integrated electromagnetic coil adopts an overlapping loop; move and measure successively to obtain the electromagnetic response signal difference between the center measurement point of the heading face and the measurement points in the left, top, right, and bottom directions of the tunnel roadway rock wall.

[0034] Let the received electromagnetic response of a set of transceiver-integrated electromagnetic coils at the center measurement point of the heading face be R掌中, and the received electromagnetic response signals of the receiving coils corresponding to the measurement points in each direction be R左, R顶, R右, and R底. Take the response of the set of transceiver coils at the heading face as positive "+"; The data of the electromagnetic response signal differences between the heading face and the measurement points in each direction of the tunnel roadway rock wall measured by the electromagnetic method detector are respectively: R掌中 - R左, R掌中 - R顶, R掌中 - R右, R掌中 - R底; Compare the magnitudes of the response difference data corresponding to the above-mentioned measurement points in each direction, and take the data of the direction where the maximum value of "+" is located, marked as: R0 = R掌中 - Rb; R0 is the direction where the maximum response difference is located, and the direction where the measurement point Rb is located is the direction with the smallest abnormal electromagnetic response of itself. This direction is set as the direction where there is no potential hazard and is selected as the background direction; The measurement results of this embodiment are as Figure 4 , Figure 4 is the electromagnetic response signal difference between the center measurement point of the heading face and the four measurement points in the directions of the tunnel roadway rock wall; Figure 4 In, "left side" represents the electromagnetic response signal difference "R掌中 - R左", "right side" represents the electromagnetic response signal difference "R掌中 - R右", "top" represents the electromagnetic response signal difference "R掌中 - R顶", and "bottom" represents the electromagnetic response signal difference "R掌中 - R底"; it should be noted that Figure 4 In, it contains four groups of signal differences. The starting points of the vertical axes of each group of signal difference curves (i.e., V( t ) / I = 0) are different. On the vertical axis, from top to bottom, the starting points of "R掌中 - R底", "R掌中 - R右", "R掌中 - R顶", and "R掌中 - R左" are in turn; it can be seen from the figure that the signal difference curves V( t ) / I corresponding to the "left side" and "top" are mostly less than 0, and the signal difference curves V( t ) / I corresponding to the "bottom" and "right side" are greater than 0, and the peak value of the signal difference curve of the "bottom" is greater than that of the "right side". Therefore, the response signal difference of the measurement point at the "bottom" of the tunnel rock wall is the largest. Therefore, the measurement point at the bottom is used as the measurement point Rb, and the bottom direction is the background direction.

[0035] Further obtain the response data of other orientations relative to the background orientation of the tunnel rock wall measuring point Rb: Subtract the electromagnetic response signal difference data corresponding to other azimuth measuring points from R0, that is, subtract R palm - R left, R palm - R top, and R palm - R right from R0 = R palm - Rb. Since the set of transceiver electromagnetic coils arranged at the measuring point in the center of the face remains stationary during the differential measurement process, the receiving response of the measuring point in the center of the face represented by R palm is the same, so the electromagnetic response signal difference data of R1 = R left - Rb, R2 = R top - Rb, and R3 = R right - Rb are obtained. The electromagnetic response signal difference data of the measuring point in the center of the face relative to the background azimuth measuring point Rb is R0 = R palm - Rb. The electromagnetic response signal difference data of the three azimuth measuring points on the tunnel rock wall and the measuring point in the center of the face relative to the background azimuth measuring point are as follows: Figure 5 In the figure, "left side" represents the signal difference R1=Rleft-Rb, "top" represents the signal difference R2=Rtop-Rb, "right side" represents the signal difference R3=Rright-Rb, and "palm" represents the signal difference R0=Rpalm-Rb. The vertical axis starting point of each group of signal difference curves (i.e., V( t ) / I=0) are all different. On the vertical axis, from top to bottom they are R0, R3, R2, and R1.

[0036] Compare the amplitude changes of R0, R1, R2, and R3. The more prominent the amplitude change, the greater the possibility and scale of the hidden danger. The comparison of amplitude changes includes two aspects, one is the absolute amplitude, and the other is the speed at which the amplitude decays over time. The larger the absolute amplitude, that is, the larger the abnormal response amplitude (the stronger the energy that hinders the decay of the primary field or the slower the decay of the time-varying abnormal field), the greater the abnormal degree or scale of the low-resistance hidden danger (possibly the better the conductivity, the larger the volume, or the closer to the detection working surface); the smaller the speed at which the amplitude decays over time (or the slower the decay), the greater the abnormal degree or scale.

[0037] In this embodiment, from Figure 5 It can be seen that the absolute amplitude of the electromagnetic response signal difference R3=Rright-Rb is the smallest and the amplitude decays faster over time, followed by the electromagnetic response signal difference R0=Rpalm-Rb, the electromagnetic response signal difference R1=Rleft-Rb has the slowest amplitude decay over time, the electromagnetic response signal difference R2=Rtop-Rb has the largest absolute amplitude, and the amplitude changes of R1 and R2 are the most prominent. Then, according to the electromagnetic response signal differences R1 and R2, the abnormal geological position and distribution range around the corresponding azimuth measurement points are interpreted.

[0038] This embodiment uses the late apparent resistivity conversion algorithm for interpretation, and the late apparent resistivity calculation formula of the overlapping loop is: ρ = 6.32 × 10-3 ×L 4 / 3 S 2 / 3 ×[V(t) / I] -2 / 3 × t -5 / 3 in: ρ is the apparent resistivity, in Ω·m; L is the coil side length, in m; S is the receiving area, in m 2 ; V( t ) / I is the data value of the normalized electromagnetic response signal difference, in units of uV / A; t It is the measurement time (i.e. the time required for the electromagnetic response signal to reach the corresponding depth), in ms.

[0039] like Figure 6 , Figure 6 This is a pseudo-section diagram of apparent resistivity obtained by conversion using the late apparent resistivity calculation formula (the transceiver coil is an overlapping loop). White represents the location with low resistivity, black represents the location with high resistivity, and gray represents the transition from black to white. Figure 6 It can be seen that the apparent resistivity is the highest at the bottom and right side of the tunnel, and it is judged that there is no hidden danger of water storage (the diagrams at the bottom and right side of the tunnel are used for comparison and verification, and no interpretation is required during specific implementation); the apparent resistivity is low on the left and top of the tunnel, and it is preliminarily judged that there is a hidden danger of water storage. The apparent resistivity of the left side (the left measuring point is relative to the measuring point at the center of the face) is even lower, indicating that the possibility and scale of the hidden danger are greater. Specifically, the low-resistance hidden danger mainly exists on the left side, which can be roughly divided into two sections. The most serious low-resistance hidden danger exists at a depth of 80-90m, especially in the depth range of 85-95m. There are also low-resistance hidden dangers at 100m to deeper positions, but their low-resistance values ​​are lower than those at a depth of 80-90m.

[0040] Traffic tunnels generally refer to construction tunnels for subways, high-speed railways, and highways. The low-resistance hidden dangers they face are generally concealed water storage structures. These water disasters may exist in karst caves and fault fracture zones.

[0041] When measuring with the transient electromagnetic method, the response of the secondary electromagnetic field (including the response of low-resistivity hidden dangers that may exist inside the detected area) is measured at the moment the primary electromagnetic field is turned off. If there are no low-resistance hidden dangers around, the secondary electromagnetic field will quickly decay to zero. When the secondary electromagnetic field slowly decays to zero, it means that there are low-resistance hidden dangers (such as water-rich water bodies) around. The slower the decay, the larger the scale of the hidden danger, the better the water-richness, or the closer the distance. In the present invention, differential measurement is firstly performed between the measuring point at the center of the face and each measuring point on the rock wall of the tunnel to obtain electromagnetic response signal difference data (such as Rpalm-Rleft) to eliminate the interference of the primary electromagnetic field signal; then, according to the attenuation law of the secondary electromagnetic field, the orientation where the maximum response difference is located is determined as the background orientation (R0=Rpalm-Rb), the surrounding rock mass revealed by the background orientation is the most normal, and the probability of the existence of low-resistance hidden dangers around the measuring point Rb is the smallest, based on the background orientation, R1, R2, R3, and R0 are compared, and the electromagnetic response signal difference with the largest absolute amplitude and the slowest amplitude decay over time is selected from Ri and R0, so as to determine that the corresponding orientation has a low-resistance hidden danger, that is, abnormal geology or mineral resources.

[0042] In other embodiments, it may be predicted that there is a hidden danger of water storage at the center measuring point (in front) of the face. In this way, the location of abnormal geology in front of the face can be further predicted by the following method: using the aforementioned background orientation (such as the bottom) measuring point as a reference and the center measuring point of the face as a benchmark, one measuring point is arranged in each of the four orientations of the face, namely, up, down, left, and right (close to the face contour), and the electromagnetic method is used to perform differential measurement between any orientation measuring point of the face and the background orientation measuring point. The measurement can be performed in the up, down, left, and right orientations to obtain the electromagnetic response signal difference between each orientation measuring point of the face and the background orientation measuring point. According to the electromagnetic response signal difference with the largest difference, the electromagnetic response interpretation algorithm is used to interpret the location of the abnormal geology. The larger the difference, the more accurate the location of the abnormal geology obtained by interpreting the corresponding electromagnetic response signal difference.

[0043] It should be noted that the above-mentioned advanced geological prediction method can be used in the excavation projects of underground mining tunnels including metal, non-metallic mines and coal mines, to predict the water storage structure in front of the tunnel face and implement advanced geological exploration; it can also be used in the excavation projects of underground mining tunnels to predict the detection of hidden mineral resources around the tunnels including the face, especially the detection of metal ore bodies.

[0044] It should be noted that the method of the present invention can be implemented by hardware, software or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. A person of ordinary skill in the art will understand that the above-mentioned device and method can be implemented using computer executable instructions and / or contained in a processor control code, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. Such code is provided on the carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The device of the present invention and its modules can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0045] The instruments, equipment, electromagnetic method and interpretation method used in the present invention are all based on the existing technology. The improvement lies in the ingenious application of the existing technology to advanced geological exploration according to the method described in the present invention to improve the accuracy of the exploration results. The improvement of its implementation method is based on the above-mentioned improvement, and the supporting hardware and software can refer to the existing technology.

[0046] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit it. Any modification or replacement of the technical solution made by other technicians in this professional field should be included in the scope of the claims of the present invention as long as it does not deviate from the connotation of the technical solution of the present invention.

Claims

1. A method for advanced geological prediction of tunnel excavation, characterized in that: The steps include: Arrange one measuring point at the center of the tunnel face; A cross section parallel to the tunnel face is selected behind the tunnel face, and one measuring point is arranged at each of the four positions on the left side, top, right side and bottom of the tunnel rock wall corresponding to the cross section; The electromagnetic method is used to perform differential measurement between the measuring point at the center of the tunnel face and any measuring point on the tunnel rock wall, and the electromagnetic response signal difference between the measuring point at the center of the tunnel face and each measuring point on the tunnel rock wall is obtained. The tunnel rock wall orientation where the maximum electromagnetic response signal difference R0 is located is marked as the background orientation. The electromagnetic response signal differences Ri of the other three azimuth measuring points on the tunnel rock wall relative to the background azimuth measuring point are calculated respectively, where i=1, 2, and 3. The electromagnetic response signal difference with the largest absolute amplitude and the slowest amplitude decay over time is selected from Ri and R0, and the electromagnetic response interpretation algorithm is used to interpret the azimuth and distribution characteristics of the abnormal geology.

2. The method according to claim 1, characterized in that: The electromagnetic method is one of the transient electromagnetic method, the frequency depth sounding electromagnetic method with variable frequency or frequency combination, and the geological radar method.

3. The method according to claim 1, characterized in that: When the electromagnetic method is used for differential measurement, a set of transceiver electromagnetic coils are installed at each of the two measuring points; in the two sets of transceiver electromagnetic coils, the transmitting coil is connected to the transmitting end of the electromagnetic detector in series or in parallel, and the receiving coil is connected to the receiving end of the electromagnetic detector in series or in parallel.

4. The method according to claim 3, characterized in that: The two sets of electromagnetic coils for transmitting and receiving are used in one mode: one transmitting and one receiving, one transmitting and two receiving, two transmitting and one receiving, or two transmitting and two receiving.

5. The method according to claim 3, characterized in that: In the transceiver integrated electromagnetic coil, the transmitting coil or the receiving coil both adopts a magnetic rod with a built-in soft magnetic core or a Hall sensor; or, the transmitting coil is a power supply electrode, and the receiving coil is a receiving electrode.

6. The method according to claim 1, characterized in that: The electromagnetic response interpretation algorithm adopts one of a one-dimensional electromagnetic inversion method, a two-dimensional electromagnetic inversion method, a three-dimensional electromagnetic inversion method, an early apparent resistivity conversion algorithm, a late apparent resistivity conversion algorithm, a power spectrum anomaly analysis method, and an entropy spectrum anomaly analysis method.

7. The method according to claim 1, characterized in that: When abnormal geology is predicted ahead of the measuring point at the center of the tunnel face, the location of the abnormal geology ahead of the measuring point at the center of the tunnel face is further predicted by the following method: Taking the measuring point at the center of the tunnel face as the reference, one measuring point is arranged in each of the four directions of the top, bottom, left and right of the tunnel face. The electromagnetic method is used to perform differential measurement between any measuring point in any direction of the tunnel face and the measuring point in the background direction, and the electromagnetic response signal difference between each measuring point in the direction of the tunnel face and the measuring point in the background direction is obtained. The response signal difference with the largest absolute amplitude and the slowest amplitude decay over time is selected, and the electromagnetic response interpretation algorithm is used to interpret the location and distribution characteristics of the abnormal geology.

8. A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the method according to any one of claims 1 to 7.

9. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the method according to any one of claims 1 to 7.

10. An information data processing terminal, wherein the information data processing terminal is used to implement the method according to any one of claims 1 to 7.

Images