A more accurate tunnel geological advance prediction method and detector coupling device

Abstract

The application discloses a more accurate tunnel geological advanced prediction method and a detector coupling device, and the geological prediction process comprises the following steps: step one, tunnel geological exploration is carried out to master the completeness of the tunnel face; step two, drilling holes are arranged according to the completeness of the tunnel face, and each drilling hole corresponds to an excitation point; step three, detector strings are arranged according to the number of drilling holes; step four, each detector string is connected with a TGS host; step five, an SGD-SHC hammer source synchronous system excitation device is installed; step six, the hammer head of the SGD-SHC hammer source synchronous system sequentially excites each excitation point; step seven, the detector string is moved along the drilling hole diameter; step eight, data is collected, and a time-depth curve is drawn; step nine, a wave velocity-depth curve is obtained through inversion; step ten, a longitudinal wave velocity curve is obtained through the wave velocity-depth curve; and step eleven, a corresponding atlas is formed, the atlas is interpreted, and the geological structure in a certain range in front of the tunnel face and the adverse geological features can be identified.

Description

Technical Field

[0001] This invention belongs to the field of tunnel geological advance prediction, and more specifically, it is a more accurate tunnel geological advance prediction method and detector coupling device. Background Technology

[0002] While current seismomagnetic methods can effectively detect unknown adverse geological bodies in tunnels, the data analysis based on a single method is inefficient and inaccurate, making it impossible to make accurate predictions before construction and thus effectively improve construction safety. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides a more accurate method for tunnel geological advance prediction and a detector coupling device. By combining the two detection methods, the accuracy of tunnel advance prediction can be effectively improved. Through the detector coupling device, the detector is fully coupled with the borehole, further improving the detection accuracy.

[0004] Technical Solution: To achieve the above objectives, the present invention provides a more accurate method for advance geological prediction of tunnels, characterized in that the geological prediction process includes the following steps:

[0005] Step 1: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to determine the integrity of the rock mass at the tunnel face;

[0006] Step 2: Arrange boreholes according to the integrity of the surrounding rock at the working face, and set a trigger point around the perimeter of each borehole;

[0007] Step 3: Arrange the detector strings according to the number of boreholes. Each detector string should include at least three detector units. After each detector string is installed in the borehole, the coupling structure of each detector unit will couple each detector unit to the borehole wall.

[0008] Step 4: Connect the end of each detector string closest to the borehole opening to the TGS host.

[0009] Step 5: Install the excitation device of the SGD-SHC hammer source synchronization system. The excitation trigger of the excitation device uses the SGD-SAH accelerometer and is connected to the TGS host via wired or wireless means.

[0010] Step 6: The excitation trigger mounted on the side of the hammer head of the SGD-SHC hammer source synchronization system is used to excite each excitation point in sequence, generating elastic wave signals on the surrounding rock of the working face. The detector string can collect the elastic wave signals.

[0011] Step 7: Move the geophone string multiple times at equal intervals from the inside to the outside along the borehole diameter, so that the geophone string can sequentially collect the time (t0) data of the elastic waves generated by the hammer head of the SGD-SHC hammer source synchronization system on the surrounding rock of the working face at each position.

[0012] Further, step eight: Based on the collected data, plot the time-depth curve;

[0013] Step 9: Calculate the elastic wave travel distance ΔL for each data point based on the coordinates of the excitation point and the detector string. Obtain the comprehensive rock mass wave velocity V1 at this distance using V1=2×ΔL / t0. After obtaining the wave velocities of all collected data, perform inversion to obtain the wave velocity-depth curve.

[0014] Step 10: Process the wave velocity-depth curve data using the processing software in the TGS host to obtain the P-wave velocity curve, and use this curve to continuously revise the initial wave velocity model. Finally, based on the empirical correction formula for wave velocity, calculate the comprehensive velocity of the surrounding rock in front of the tunnel face and generate a parameter map;

[0015] Step 11: Based on the comprehensive velocity of the surrounding rock in front of the tunnel face, the corresponding map is generated by the processing software in the TGS host. By interpreting the map, the geological structure within a certain range in front of the tunnel face can be identified, as well as adverse geological features can be detected.

[0016] Furthermore, the process for identifying unfavorable geological areas includes the following steps:

[0017] Step A: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to obtain the integrity of the rock mass at the tunnel face;

[0018] Step B: Select the detection method based on the integrity of the rock mass at the working face. If the integrity of the working face is high, use the continuous detection method; if the integrity of the working face is low, use the point detection method.

[0019] Step C: Based on the selected detection method, lay out survey lines on the working face, and set a trigger point every A distance along the survey lines;

[0020] Step D: Deploy the receiver and radar instrument, and connect the receiver and radar instrument wirelessly;

[0021] Step E: Move the ground-penetrating radar antenna from one end of the survey line to the other end. At each trigger point, attach the radar antenna to the survey line and control the radar to generate high-frequency narrow-pulse electromagnetic waves. The high-frequency narrow-pulse electromagnetic waves are transmitted to the unknown area of ​​the working face through the radar antenna. The receiver can detect the reflected or directly transmitted signals generated by the high-frequency narrow-pulse electromagnetic waves in the rock layer, amplify and digitize them, and store them on a digital magnetic tape recorder for data processing and display.

[0022] Step F: Perform data cleaning, filtering, data interpolation, and resampling on the reflected or directly transmitted signals stored on the digital magnetic tape recorder by the receiver, so that the acquired data can be presented graphically by the corresponding software.

[0023] Step G: Based on the map, it is possible to effectively determine whether the unfavorable geological area in front of the tunnel face is a hidden fracture zone or a water-related geological area.

[0024] Furthermore, the forecasting process for the specific location and extent of water-related geological areas includes:

[0025] Step S1: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to understand the various geological conditions of the surrounding rock at the tunnel face;

[0026] Step S2: Power supply electrodes B1, B2, and B3 are arranged at certain intervals along the width direction of the working face behind the working face. Power supply electrodes B1, B2, and B3 supply power to the ground. A fixed electrode A is set on the side of power supply electrode B3 away from power supply electrode B3 along the width direction of the working face.

[0027] Step S3: Two movable measuring electrodes M and N are set between the fixed electrode A and the power supply electrode B3. The fixed electrode A, measuring electrodes M and N, and power supply electrodes B1, B2, and B3 are all located on the same straight line. The initial position of measuring electrodes M and N is located on the side of power supply electrode B3 closer to the fixed electrode A. The fixed electrode A is connected to the receiving device via wired or wireless means.

[0028] Step S4: Move the movable electrodes M and N along the line connecting the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 towards the fixed electrode A. Each time the electrodes move a distance B, the two measuring electrodes M and N are driven into the ground. At this time, the receiving device can measure the potential difference ΔV between the two electrodes M and N, and calculate the resistivity value ρs at the midpoint between the M and N electrodes according to the common formula ρs=KΔV / I. The calculated resistivity values ​​ρs are stored on the digital magnetic tape recorder for data processing and display.

[0029] Step S5: Plot a resistivity curve based on the measured resistivity value ρs;

[0030] Step S6: Based on the resistivity curve, a geological structure map is drawn using appropriate software to determine the location and extent of water-bearing structures within the rock strata.

[0031] Furthermore, when the geological forecast indicates unfavorable geological features in the geological structure within a certain range ahead of the tunnel face, it is necessary to determine the unfavorable geological area and its category. If the interpretation of the combined geological forecast results and the unfavorable geological area determination results indicates that the unfavorable geological structure ahead of the tunnel face is a hidden crack, it is necessary to improve the seismic resistance and load-bearing capacity of the tunnel structure in that area. If the interpretation of the combined geological forecast results and the unfavorable geological area determination results indicates that the unfavorable geological structure ahead of the tunnel face is a water-related area, it is necessary to predict the specific location and extent of the water-related geological area to obtain the distribution and extent of the water-related area. This will enable accurate grouting and sealing of the water-related area during construction, preventing the water-related area from affecting the construction progress.

[0032] Furthermore, a detector coupling device for a more accurate tunnel geological advance prediction method includes a detector, an annular coupling wall coaxially sleeved on the outer side of the detector, and an expandable annular deformation layer coaxially arranged around the outer periphery of the coupling wall.

[0033] Furthermore, an annular injection groove is provided at the center of the circumference of the coupling wall, and several injection holes are provided at one end of the coupling wall. Each injection hole is connected to the injection groove. There is an annular gap between the coupling wall and the deformation layer, and the annular gap is connected to the injection groove.

[0034] Furthermore, annular sealing mounting grooves are provided at both ends of the annular coupling wall circumference, and the two ends of the deformable layer are sealed and fixed in the two mounting grooves along the contour.

[0035] Beneficial effects: The present invention provides a more accurate tunnel geological advance prediction method and a detector coupling device. By combining two detection methods, it can effectively improve the accuracy of tunnel advance prediction. Through the detector coupling device, the detector is fully coupled with the borehole, further improving the detection accuracy. Attached Figure Description

[0036] Figure 1 This is a flowchart of the geological prediction process of the present invention;

[0037] Figure 2 This is a schematic diagram of the layout of the geological radar survey lines according to the present invention;

[0038] Figure 3 This is a schematic diagram of the DC electrical measurement setup of the present invention.

[0039] Figure 4 This is a schematic diagram of the detector coupling device of the present invention;

[0040] Figure 5 This represents state A of the detector coupling device of the present invention in the borehole;

[0041] Figure 6This is state B of the detector coupling device of the present invention in the borehole;

[0042] Figure 7 This is an axial view of a common detector installed in a borehole. Detailed Implementation

[0043] The invention will now be further described with reference to the accompanying drawings.

[0044] As attached Figures 1-6 As shown, a more accurate method for tunnel geological advance prediction includes the following steps in the geological prediction process:

[0045] Step 1: Professional personnel will inspect the geological and geographical environment of different areas and locations in the tunnel, conduct investigations and sampling, examine the samples, conduct preliminary exploration of the unknown areas of the tunnel face ahead, and measure the integrity of the rock mass at the tunnel face.

[0046] Step 2: Arrange boreholes according to the integrity of the surrounding rock at the working face, and set a trigger point around each borehole.

[0047] Step 3: Arrange the detector strings according to the number of boreholes. Each detector string should include at least three detector units. After each detector string is installed in the borehole, the coupling structure of each detector unit will couple each detector unit to the borehole wall.

[0048] Step 4: Connect the end of each detector string near the borehole opening to the TGS host.

[0049] Step 5: Install the excitation device of the SGD-SHC hammer source synchronization system. The excitation trigger of the excitation device uses the SGD-SAH accelerometer and is connected to the TGS host via wired or wireless means.

[0050] Step Six: The excitation trigger mounted on the side of the hammer head of the SGD-SHC hammer source synchronization system is used to excite each excitation point in sequence, generating elastic wave signals on the surrounding rock of the working face. The detector string can collect the elastic wave signals.

[0051] Step 7: After one excitation, move the geophone string multiple times at equal intervals along the borehole diameter from the inside of the borehole to the outside of the borehole. After each movement of the geophone string, the excitation device of the SGD-SHC hammer source synchronization system needs to be repositioned to the excitation point for another strike. This allows the geophone string to sequentially collect the time (t0) data of the elastic wave generated by the SGD-SHC hammer source synchronization system hammer head on the surrounding rock at the working face at each location. The moving distance of the geophone string is n × L, where n is the number of geophones and L is the spacing between two adjacent geophones. Move the geophone string until the distance between the probe of the geophone closest to the TGS host and the borehole opening is less than L.

[0052] Step 8: Based on the collected data, plot the time-depth curve;

[0053] Step 9: Calculate the elastic wave travel distance ΔL for each data point based on the coordinates of the excitation point and the detector string. Obtain the comprehensive rock mass wave velocity V1 at this distance using V1=2×ΔL / t0. After obtaining the wave velocities of all collected data, perform inversion to obtain the wave velocity-depth curve.

[0054] Step 10: Process the wave velocity-depth curve data using the processing software in the TGS host to obtain the P-wave velocity curve, and continuously revise the initial wave velocity model using this curve. Finally, based on the empirical correction formula for wave velocity, calculate the comprehensive velocity of the surrounding rock ahead of the tunnel face and generate a parameter map; the empirical correction formula for wave velocity is as follows: v is the overall velocity of the surrounding rock in front of the tunnel face, β is the correction factor for the corresponding geology, h is the approximate location of adverse geology obtained after combining excavation verification data, h0 is the location of adverse geological anomalies predicted by the TGS host, and v0 is the P-wave velocity in the predicted initial velocity model.

[0055] Step 11: Perform data parameter collaborative inversion on the collected data and survey parameters to conduct an overall geological assessment of the exploration area in front of the tunnel face. Based on the comprehensive velocity of the surrounding rock in front of the tunnel face, generate corresponding maps through the processing software in the TGS host. Interpreting the maps can identify geological structures within a certain range in front of the tunnel face and detect adverse geological features. In this embodiment, after setting the interpretation map, geological structures within a 100-meter range in front of the tunnel face can be identified.

[0056] When interpreting the geological structure within a certain range in front of the tunnel face, if adverse geological features are found in the forecast, it is necessary to determine the type of adverse geological features.

[0057] The process for determining adverse geological conditions includes the following steps:

[0058] Step A: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to obtain the integrity of the rock mass at the tunnel face;

[0059] Step B: Select the detection method based on the integrity of the rock mass at the working face. If the integrity of the working face is high, use the continuous detection method; if the integrity of the working face is low, use the point detection method.

[0060] Step C: Based on the selected detection method, lay out survey lines on the tunnel face, such as... Figure 2 As shown, a trigger point is set every A distance along the survey line;

[0061] Step D: Deploy the receiver and radar instrument, and connect the receiver and radar instrument wirelessly;

[0062] Step E: Move the ground-penetrating radar antenna along the survey line from one end to the other. At each trigger point, attach the radar antenna to that point and control the radar to generate high-frequency narrow-pulse electromagnetic waves. These waves are transmitted through the radar antenna to the unknown area of ​​the tunnel face. The receiver detects the reflected or directly transmitted signals generated by these waves within the rock layer, amplifies and digitizes them, and stores them on a digital magnetic tape recorder for data processing and display. Because ground-penetrating radar has sufficient penetration and resolution, detailed exploration is required to obtain more accurate geological information. Therefore, in this embodiment, distance A in step C is set to 0.2m.

[0063] Step F: Perform data cleaning, filtering, data interpolation, and resampling on the reflected or directly transmitted signals stored on the digital magnetic tape recorder by the receiver, so that the acquired data can be presented graphically by the corresponding software.

[0064] Step G: By interpreting TGS images in conjunction with ground-penetrating radar images, lithological interfaces can be accurately identified, and hidden fracture zones can be identified, thereby improving the accuracy of surrounding rock exploration. Based on the map, it is possible to effectively determine whether the unfavorable geological area in front of the tunnel face is a hidden fracture zone or a water-related geological area.

[0065] If the interpretation of the combined geological forecast results and the results of the judgment of unfavorable geological areas indicates that the unfavorable geological structure in front of the tunnel face is a hidden crack, it is necessary to improve the seismic resistance and load-bearing capacity of the tunnel structure in that area. If the interpretation of the combined geological forecast results and the results of the judgment of unfavorable geological areas indicates that the unfavorable geological structure in front of the tunnel face is a water-related area, it is necessary to predict the specific location and water-related range of the water-related geological area.

[0066] The process for forecasting the specific location and extent of water-related geological areas includes:

[0067] Step S1: Explore the geological environment of different tunnels in different regions, conduct preliminary geological exploration of the tunnels, and obtain data on the dip angle of the surrounding rock at the tunnel face;

[0068] Step S2: As Figure 3 As shown, power supply electrodes B1, B2, and B3 are arranged at certain intervals along the width of the working face behind the working face. Power supply electrodes B1, B2, and B3 supply power to the ground. A fixed electrode A is set on the side of power supply electrode B3 away from power supply electrode B1 along the width of the working face. Let the distance between electrode B1 and electrode B3 be L1, and the distance between electrode B3 and electrode A be L2, where L2 = 3L1~5L1.

[0069] Step S3: Two movable measuring electrodes M and N are set between the fixed electrode A and the power supply electrode B3. The fixed electrode A, measuring electrodes M and N, and power supply electrodes B1, B2, and B3 are all located on the same straight line. The initial position of measuring electrodes M and N is located on the side of power supply electrode B3 closer to the fixed electrode A. The fixed electrode A is connected to the receiving device via wired or wireless means.

[0070] Step S4: Move the movable electrodes M and N along the line connecting the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 towards the fixed electrode A. Each time the electrodes move a distance B, the two measuring electrodes M and N are driven into the ground. At this time, the receiving device can measure the potential difference ΔV between the two electrodes M and N, and calculate the resistivity value ρs at the midpoint between the M and N electrodes according to the formula ρs=KΔV / I. The calculated resistivity values ​​ρs are stored on a digital magnetic tape recorder for data processing and display. The higher the water content and the higher the water mineralization, the lower the rock resistivity; the lower the water content and the lower the water mineralization, the higher the rock resistivity. However, since this resistivity change is relatively small within a small range, a detection range with a certain length is more convenient for detection. Therefore, in this embodiment, the distance B is set to 4m, and the length L1 is greater than 4m.

[0071] Step S5: Plot a resistivity curve based on the measured resistivity value ρs. Interpret the obtained resistivity distribution image. By analyzing the conductivity differences between different media, the accurate distribution location of the water body can be obtained.

[0072] Step S6: Based on the resistivity curve, a geological structure map is drawn using appropriate software. The image is then interpreted in conjunction with the ground-penetrating radar image to determine the location and extent of the water-bearing structure in the rock strata near the tunnel working face.

[0073] By combining the results of the assessment of adverse geological areas with the interpretation of the specific location and water-related range forecast of water-related geological areas, the distribution and range of water-related areas can be accurately determined. This allows for precise grouting and sealing of water-related areas during construction, preventing water-related areas from affecting the construction process.

[0074] like Figure 7 As shown, in step three of the geological prediction process, the geophone needs to be successfully installed into the borehole. The borehole diameter needs to be slightly larger than the geophone. Since the geophone is usually cylindrical, it makes point contact with the borehole when it is installed. Moreover, the common method of coupling between the geophone and the borehole is to evenly apply grease to the outer wall of the geophone. However, since the density of grease is much different from that of rock, and the geophone itself heats up during the detection process, the grease will melt, causing the geophone to detach from the borehole wall and increasing the error of the geophone detection results.

[0075] like Figure 4 As shown, the detector coupling device of the tunnel geological advance prediction method of this scheme includes a detector 1. An annular coupling wall 2 is coaxially sleeved on the outer side of the detector 1, and the coupling device is fixedly set relative to the detector 1. An expandable annular deformation layer 4 is provided on the periphery of the coupling wall 2. When the detector 1 is placed in a predetermined position in the borehole, a coupling fluid with a density similar to that of the rock is injected into the coupling wall 2, and the deformation layer 4 expands outward and presses against the borehole wall 8.

[0076] Both ends of the coupling wall 2 are provided with annular sealing installation grooves 3. The two ends of the deformation layer 4 are respectively sealed and fixed in the two sealing installation grooves 3. The sealing installation method of the deformation layer 4 can be to use a sealing adhesive to seal the two ends of the deformation layer 4 in the two sealing installation grooves 3 respectively. In this embodiment, the two ends of the deformation layer 4 near the coupling wall 2 are sealed and connected with sealing rings 9. The width of the sealing rings 9 is slightly larger than the width of the installation grooves 3. The two ends of the deformation layer 4 are sealed and fixed in the two installation grooves 3 along the contour. The deformation layer 4 is a flexible material with a density similar to that of rock.

[0077] An annular injection groove 7 is formed at the center of the circumference of the coupling wall 2. Several injection holes 6 are formed at one end of the coupling wall 2, evenly distributed in a circular array. Each injection hole 6 is connected to the injection groove 7. A coupling fluid pipe 10 is sealed and connected to the end of each injection hole 6 away from the injection groove 7. The other end of the coupling fluid pipe 10 is connected to a pressurizing device. The pressurizing device can inject coupling fluid into the injection groove 7 through the injection holes 6 and the coupling fluid pipe 10. An annular gap 5 exists between the coupling wall 2 and the deformation layer 4, and the annular gap 5 is connected to the injection groove 7. Figure 5 As shown, during the installation of the detector 1 and the coupling device into the borehole, the deformed layer 4 comes into contact with the borehole wall at point 8.

[0078] like Figure 6 As shown, after the coupling device and the detector are installed in the borehole, the pressurizing device injects a coupling fluid with a density similar to that of the rock into the injection tank 7 and the annular gap 19 through the coupling fluid pipe 10. As the amount of injected coupling fluid increases, the deformation layer 4 will expand and deform in a direction away from its own axis until the outer circumferential surface of the deformation layer 4 is tightly pressed against the borehole wall 8, so that the detector 1 is fully coupled with the borehole wall 8 as much as possible, ensuring the accuracy of the detection results of the detector 1.

[0079] Common rock densities range from 2.5 g / cm³ to 3 g / cm³. Therefore, in this embodiment, polytetrafluoroethylene (PTFE), with a similar density, is selected as the material for the deformation layer 4. The injected liquid is potassium nitrate solution with a similar density. The coupling wall 2 is integrally cast from an alloy material with a similar density and stable chemical properties. This ensures that the transmission effect of vibration waves by the deformation layer 4, coupling liquid, and coupling wall 2 is as close as possible to the transmission effect of vibration waves by the rock, thereby further reducing the error in the detection process of the detector 1 and ensuring the accuracy of the detection results of the detector 1.

[0080] The above are the preferred embodiments described in this invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. A method for advanced geological prediction of tunnels, characterized in that: The geological forecasting process includes the following steps: Step 1: Conduct preliminary geological exploration of the tunnel to determine the integrity of the rock mass at the tunnel face; Step 2: Arrange boreholes according to the integrity of the surrounding rock at the working face, and set a trigger point around the perimeter of each borehole; Step 3: Arrange the detector strings according to the number of boreholes. Each detector string should include at least three detector units. After each detector string is installed in the borehole, the coupling structure of each detector unit will couple each detector unit to the borehole wall. Step 4: Connect each detector in series to the TGS main unit at the end closest to the borehole opening; Step 5: Install the excitation device of the SGD-SHC hammer source synchronization system. The excitation trigger of the excitation device uses the SGD-SAH accelerometer and is connected to the TGS host via wired or wireless means. Step 6: The excitation trigger mounted on the side of the hammer head of the SGD-SHC hammer source synchronization system is used to excite each excitation point in sequence, generating elastic wave signals on the surrounding rock of the working face. The detector string can collect the elastic wave signals. Step 7: Move the geophone string multiple times at equal intervals from the inside to the outside along the borehole diameter, so that the geophone string can sequentially collect the time t0 data of the elastic wave generated by the hammer head of the SGD-SHC hammer source synchronization system on the surrounding rock of the working face at each position. The process for determining adverse geological conditions includes the following steps: Step A: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to obtain the integrity of the rock mass at the tunnel face; Step B: Select the detection method based on the integrity of the rock mass at the working face. If the integrity of the working face is high, use the continuous detection method; if the integrity of the working face is low, use the point detection method. Step C: Based on the selected detection method, lay out survey lines on the working face, and set a trigger point every A distance along the survey lines; Step D: Deploy the receiver and radar instrument, and connect the receiver and radar instrument wirelessly; Step E: Move the ground-penetrating radar antenna from one end of the survey line to the other end. At each trigger point, attach the radar antenna to the survey line and control the radar to generate high-frequency narrow-pulse electromagnetic waves. The high-frequency narrow-pulse electromagnetic waves are transmitted to the unknown area of ​​the working face through the radar antenna. The receiver can detect the reflected or directly transmitted signals generated by the high-frequency narrow-pulse electromagnetic waves in the rock layer, amplify and digitize them, and store them on a digital magnetic tape recorder for data processing and display. Step F: Perform data cleaning, filtering, interpolation, and resampling on the reflected or directly transmitted signals stored on the digital magnetic tape recorder by the receiver, so that the acquired data can be presented graphically by the corresponding software. Step G: Based on the map, it is possible to effectively determine whether the unfavorable geological conditions in front of the tunnel face are hidden fracture zones or water-related geological conditions; The process for forecasting the specific location and extent of water-related geological areas includes: Step S1: Explore the geological environment of different tunnels in different regions, and conduct preliminary geological exploration of the tunnels to understand the various geological conditions of the surrounding rock at the tunnel face; Step S2: Power supply electrodes B1, B2, and B3 are arranged at certain intervals along the width direction of the working face behind the working face. Power supply electrodes B1, B2, and B3 supply power to the ground. A fixed electrode A is set on the side of power supply electrode B3 away from power supply electrode B3 along the width direction of the working face. Step S3: Two movable measuring electrodes M and N are set between the fixed electrode A and the power supply electrode B3. The fixed electrode A, measuring electrodes M and N, and power supply electrodes B1, B2, and B3 are all located on the same straight line. The initial position of measuring electrodes M and N is located on the side of power supply electrode B3 closer to the fixed electrode A. The fixed electrode A is connected to the receiving device via wired or wireless means. Step S4: Move the movable electrodes M and N along the line connecting the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 towards the fixed electrode A. Each time the electrodes move a distance B, the two measuring electrodes M and N are driven into the ground. At this time, the receiving device can measure the potential difference ΔV between the two electrodes M and N, and calculate the resistivity value ρs at the midpoint between the M and N electrodes according to the common ρs=KΔV / I. The calculated resistivity values ​​ρs are stored on the digital magnetic tape recorder for data processing and display. Step S5: Plot a resistivity curve based on the measured resistivity value ρs; Step S6: Based on the resistivity curve, a geological structure map is drawn using appropriate software to determine the location and extent of water-bearing structures within the rock strata.

2. The tunnel geological advance prediction method according to claim 1, characterized in that: Step 8: Based on the collected data, plot the time-depth curve; Step 9: Calculate the elastic wave travel distance ΔL for each data point based on the coordinates of the excitation point and the detector string. Obtain the comprehensive rock mass wave velocity V1 at this distance using V1=2×ΔL / t0. After obtaining the wave velocities of all collected data, perform inversion to obtain the wave velocity-depth curve. Step 10: Process the wave velocity-depth curve data using the processing software in the TGS host to obtain the P-wave velocity curve, and use this curve to continuously correct the initial wave velocity model. Finally, based on the empirical correction formula for wave velocity, calculate the comprehensive velocity of the surrounding rock in front of the tunnel face and form a parameter map. Step 11: Based on the comprehensive velocity of the surrounding rock in front of the tunnel face, the corresponding map is generated by the processing software in the TGS host, the map is interpreted, the geological structure within a certain range in front of the tunnel face is identified, and adverse geological features are detected.

3. The tunnel geological advance prediction method according to claim 1, characterized in that: The device includes a detector (1), on the outer side of which an annular coupling wall (2) is coaxially fitted, and on the outer periphery of the coupling wall (2) is an expandable annular deformation layer (4).

4. The tunnel geological advance prediction method according to claim 3, characterized in that: An annular injection groove (7) is provided at the center of the circumference of the coupling wall (2). A plurality of injection holes (6) are provided on one end of the coupling wall (2). Each injection hole (6) is connected to the injection groove (7). An annular gap (5) is formed between the coupling wall (2) and the deformation layer (4). The annular gap (5) is connected to the injection groove (7).

5. The tunnel geological advance prediction method according to claim 4, characterized in that: Both ends of the annular coupling wall (2) are provided with annular sealing mounting grooves (3), and both ends of the deformable layer (4) are sealed and fixed in the two mounting grooves (3) along the contour.

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