More accurate tunnel geology advanced forecasting method and detector coupling device

Abstract

The invention discloses a more accurate tunnel geology advanced forecasting method and a detector coupling device, and the geological forecasting process comprises the following steps: 1, carrying out the exploration of tunnel geology, and mastering the completeness of a tunnel face; 2, drilling holes are formed according to the completeness degree of the tunnel face, and each drilling hole corresponds to one excitation point; 3, arranging geophone strings according to the number of drill holes; 4, connecting each geophone string with a TGS host; 5, an SGD-SHC hammer source synchronous system excitation device is installed; 6, the hammer head of the SGD-SHC hammer source synchronization system sequentially excites all the excitation points; 7, moving the geophone string along the hole diameter of the drill hole; 8, collecting data, and drawing a time-depth curve; step 9, performing inversion to obtain a wave velocity-depth curve; 10, obtaining a longitudinal wave velocity curve through the wave velocity-depth curve; and 11, forming a corresponding map, interpreting the map, identifying a degree geological structure in a certain range in front of the tunnel face, and detecting unfavorable geological features.

Description

Technical Field

[0001] The present invention belongs to the field of tunnel geology advance prediction, and more specifically, relates to a more accurate tunnel geology advance prediction method and a detector coupling device. Background Art

[0002] In recent years, my country has developed rapidly in underground engineering fields such as deep mining, tunnel excavation, and rail transit. Unfavorable geological problems such as large deformation of surrounding rock and landslides occur from time to time, bringing serious safety hazards to engineering construction. Although the current seismic electromagnetic method can effectively detect unknown unfavorable geological bodies in tunnels, the data analysis based on a single method is inefficient and inaccurate, and it is impossible to effectively make accurate predictions before construction, thereby effectively improving construction safety. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a more accurate tunnel geology advance prediction method and a detector coupling device. By combining the two detection methods, the accuracy of tunnel super-strong prediction can be effectively improved. Through the detector coupling device, the detector and the borehole are fully coupled to further improve the detection accuracy.

[0004] Technical solution: To achieve the above purpose, a more accurate tunnel geology advance prediction method of the present invention is characterized in that the geological prediction process includes the following steps:

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

[0006] Step 2: Arrange the boreholes according to the integrity of the surrounding rock of the face, and set an excitation point around each of the boreholes;

[0007] Step 3: Arrange the detector strings according to the number of boreholes, each detector includes at least three detector units, and after each detector string is installed in the borehole, each detector unit is coupled to the borehole wall through the coupling structure of each detector unit;

[0008] Step 4: Connect the end of each detector string close to the borehole 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 carried on the side of the hammer head of the SGD-SHC hammer source synchronization system excites each excitation point in turn, generating elastic wave signals on the surrounding rock of the tunnel face, and the detector string can collect the elastic wave signals;

[0011] Step 7: Move the detector string multiple times along the borehole from the inside to the outside at equal intervals, so that the detector string sequentially collects 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 tunnel face received at each position;

[0012] Further, step eight: based on the collected data, draw a time-depth curve;

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

[0014] Step 10: Process the velocity-depth curve data through the processing software in the TGS host to obtain the longitudinal wave velocity curve, and use this curve to continuously correct the initial velocity model. Finally, according to the empirical correction formula of the velocity, the comprehensive velocity of the surrounding rock in front of the tunnel face is calculated and a parameter map is formed;

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

[0016] Furthermore, the process of judging the adverse geological area includes the following steps:

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

[0018] Step B: Select the detection method according to the integrity of the rock mass at the tunnel face. If the tunnel face integrity is high, the continuous detection method is selected; if the tunnel face integrity is low, the point detection method is selected;

[0019] Step C: Arrange a survey line on the tunnel face according to the selected detection method, and set a trigger point at a distance A along the survey line;

[0020] Step D: Arrange the receiver and the radar instrument, and the receiver is wirelessly connected to the radar instrument;

[0021] Step E: Move the geological radar antenna from one end of the survey line to the other end of the survey line, and each time it passes a trigger point, fit the radar antenna on the arranged survey line, control the radar to generate high-frequency narrow pulse electromagnetic waves, and transmit the high-frequency narrow pulse electromagnetic waves to the unknown area of ​​the face through the radar antenna. The receiver can detect the reflection signal or direct transmission signal derived from the high-frequency narrow pulse electromagnetic waves in the rock layer, amplify and digitize them, and store them on a digital tape recorder for data processing and display;

[0022] Step F: performing data cleaning and screening, data interpolation and resampling on the reflected signal or direct transmission signal stored in the digital tape recorder of the receiver, so that the collected data can be presented in a graphical form through corresponding software;

[0023] Step G: Based on the atlas, it can be effectively determined whether the unfavorable geological area in front of the face is a hidden fracture zone or a water-related geology.

[0024] Furthermore, the specific location of the water-related geological area and the forecast process of the water-related scope include;

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

[0026] Step S2: power supply electrodes B1, B2, and B3 are arranged at a certain interval behind the tunnel face along the tunnel face width direction, the power supply electrodes B1, B2, and B3 supply power to the ground, and a fixed electrode A is arranged on a side of the power supply electrode B3 away from the power supply electrode B3 along the tunnel face width direction;

[0027] Step S3: two movable measuring electrodes M and N are arranged between the fixed electrode A and the power supply electrode B3, the fixed electrode A, the measuring electrodes M and N, and the power supply electrodes B1, B2, and B3 are all located on the same straight line, the initial position of the measuring electrodes M and N is located on the side of the power supply electrode B3 close to the fixed electrode A, and the fixed electrode A is connected to the receiving device by wire or wirelessly;

[0028] Step S4: Move the mobile electrodes M and N along the connecting line between the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 to the fixed electrode A, and drive the two measuring electrodes M and N into the ground every time they move a distance B. 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, and store the calculated resistivity values ​​ρs on a digital tape recorder for data processing and display;

[0029] Step S5: drawing a resistivity curve diagram according to the measured resistivity value ρs;

[0030] Step S6: Draw a geological structure map based on the resistivity curve using corresponding software to determine the location and range of the water-related structure in the rock layer.

[0031] Furthermore, when the geological forecast shows adverse geological features in the forecast of the tectonic structure within a certain range in front of the tunnel face, it is necessary to make an adverse geological area judgment and an adverse geological category judgment. If the interpretation of the combined geological forecast results and the adverse geological area judgment results indicates that the adverse geology of the 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 the area. If the interpretation of the combined geological forecast results and the adverse geological area judgment results indicates that the adverse geology of the 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, and obtain the distribution location and water-related range of the water-related area, so that the water-related area can be accurately grouted and plugged during construction to prevent the water-related area from affecting the construction progress.

[0032] Furthermore, a detector coupling device for a more accurate tunnel geology advance prediction method includes a detector, an outer coaxial sleeve of the detector is provided with an annular coupling wall, and an outer coaxial sleeve of the coupling wall is provided with an expandable annular deformation layer.

[0033] Furthermore, an annular injection groove is opened at the center of the circumference of the coupling wall, and a plurality of injection holes are opened on one end of the coupling wall, each injection hole is connected to the injection groove, and an annular gap is formed between the coupling wall and the deformation layer, and the annular gap is connected to the injection groove.

[0034] Furthermore, annular sealing installation grooves are provided at both ends of the circumferential surface of the annular coupling wall, and both ends of the deformation layer are sealed and fixed in the two installation grooves along the contour.

[0035] Beneficial effect: A more accurate tunnel geological advance prediction method and detector coupling device of the present invention can effectively improve the accuracy of tunnel super-strong prediction through the combination of two detection methods. Through the detector coupling device, the detector and the borehole are fully coupled to further improve the detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is the geological prediction flow chart of the present invention;

[0037] Figure 2 It is a schematic diagram of the geological radar survey line arrangement of the present invention;

[0038] Figure 3 The schematic diagram of the DC electrical measurement arrangement of the present invention is as follows

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

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

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

[0042] Figure 7 Axial view of a typical geophone installation in a borehole. DETAILED DESCRIPTION

[0043] The present invention will be further described below in conjunction with the accompanying drawings.

[0044] As attached Figures 1 to 6 As shown in the figure, a more accurate method for advanced prediction of tunnel geology is provided. The geological prediction process includes the following steps:

[0045] Step 1: Professional personnel will detect the geological and geographical surrounding environment in different areas and locations in the tunnel, conduct investigations and sampling, check the sampled samples, conduct preliminary detection of the unknown area in front of the tunnel face in this area, and measure the integrity of the rock mass on the tunnel face.

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

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

[0048] Step 4: Connect the end of each detector string close to the borehole 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 6: The excitation trigger carried on the side of the hammer head of the SGD-SHC hammer source synchronization system excites each excitation point in turn, generating elastic wave signals on the surrounding rock of the tunnel face, and the detector string can collect the elastic wave signals.

[0051] Step 7: After completing one excitation, move the detector string multiple times along the borehole diameter from the inside of the borehole to the outside of the rotary hole at equal distances. After each movement of the detector string, the excitation device of the SGD-SHC hammer source synchronization system needs to be repositioned to the excitation point for another strike, so that the detector 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 face received at each position. The moving distance of the detector string is n×L, where n is the number of detectors and L is the distance between two adjacent detectors. Move the detector string until the distance between the probe of the detector closest to the TGS host and the borehole opening is less than L.

[0052] Step 8: Draw a time-depth curve based on the collected data;

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

[0054] Step 10: Process the velocity-depth curve data through the processing software in the TGS host to obtain the longitudinal wave velocity curve, and use this curve to continuously correct the initial velocity model. Finally, according to the empirical correction formula of the velocity, the comprehensive velocity of the surrounding rock in front of the tunnel face is calculated and a parameter map is formed; the empirical correction formula of the velocity is: v is the comprehensive 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 the unfavorable geology obtained after combining the excavation verification data, h0 is the location of the unfavorable geology anomaly 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 multiple sets of collected data and survey parameters, conduct an overall geological assessment of the detection area in front of the tunnel face, and generate a corresponding map through the processing software in the TGS host according to the comprehensive velocity of the surrounding rock in front of the tunnel face. By interpreting the map, the geological structure within a certain range in front of the tunnel face can be identified, and adverse geological features can be detected. In this embodiment, after setting the interpretation map, the geological structure within 100 meters in front of the tunnel face can be identified.

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

[0057] The process of determining the adverse geological category includes the following steps:

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

[0059] Step B: Select the detection method according to the integrity of the rock mass at the tunnel face. If the tunnel face integrity is high, the continuous detection method is selected; if the tunnel face integrity is low, the point detection method is selected;

[0060] Step C: Arrange the survey lines on the tunnel face according to the selected detection method, such as Figure 2 As shown, a trigger point is set at a distance A along the survey line;

[0061] Step D: Arrange the receiver and the radar instrument, and the receiver is wirelessly connected to the radar instrument;

[0062] Step E: Move the geological radar antenna from one end of the survey line to the other end of the survey line, and each time it reaches above a trigger point, fit the radar antenna to the trigger point, control the radar to generate high-frequency narrow pulse electromagnetic waves, and transmit the high-frequency narrow pulse electromagnetic waves to the unknown area of ​​the face through the radar antenna. The receiver can detect the reflection signal or direct transmission signal derived from the high-frequency narrow pulse electromagnetic waves in the rock layer, amplify and digitize it, and store it on a digital tape recorder for data processing and display. Since the geological radar has sufficient penetration and resolution, it is necessary to conduct detailed detection during detection in order to obtain more accurate geological information. Therefore, in this embodiment, the A distance in step C is set to 0.2m

[0063] Step F: performing data cleaning and screening, data interpolation and resampling on the reflected signal or direct transmission signal stored in the digital tape recorder of the receiver, so that the collected data can be presented in a graphical form through corresponding software;

[0064] Step G: The TGS image interpretation is combined with the geological radar image interpretation to accurately determine the lithology interface and identify hidden fracture zones, thereby improving the accuracy of surrounding rock survey. According to the atlas, it is possible to effectively determine whether the unfavorable geological area in front of the face is a hidden fracture zone geology or a water-related geology.

[0065] If the interpretation of the combined geological prediction results and the results of the bad geological area judgment indicates that the bad geology of the 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 this area; if the interpretation of the combined geological prediction results and the results of the bad geological area judgment indicates that the bad geology of the geological structure in front of the tunnel face is a water-related area, it is necessary to forecast the specific location and water-related range of the water-related geological area.

[0066] The specific location of the water-related geological area and the forecast process of the water-related scope include;

[0067] Step S1: Detect the geological environment of different tunnels in different regions, conduct preliminary exploration of the tunnel geology, and obtain the inclination data of the surrounding rock of the tunnel face;

[0068] Step S2: Figure 3 As shown, power supply electrodes B1, B2, and B3 are arranged at a certain interval behind the tunnel face along the tunnel face width direction, and the power supply electrodes B1, B2, and B3 supply power to the ground. A fixed electrode A is arranged along the tunnel face width direction on the side of the power supply electrode B3 away from the power supply electrode B1. It is assumed that the interval between electrode B1 and electrode B3 is L1, and the interval between electrode B3 and electrode A is L2, and L2=3L1~5L1.

[0069] Step S3: two movable measuring electrodes M and N are arranged between the fixed electrode A and the power supply electrode B3, the fixed electrode A, the measuring electrodes M and N, and the power supply electrodes B1, B2, and B3 are all located on the same straight line, the initial position of the measuring electrodes M and N is located on the side of the power supply electrode B3 close to the fixed electrode A, and the fixed electrode A is connected to the receiving device by wire or wirelessly;

[0070] Step S4: Move the mobile electrodes M and N along the line connecting the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 to the fixed electrode A, and drive the two measuring electrodes M and N into the ground every time they move a distance B. 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, and store the calculated resistivity values ​​ρs on a digital tape recorder for data processing and display. The more water content and the higher the mineralization of water, the lower the resistivity of the rock; the less water content and the lower the mineralization of water, the higher the resistivity of the rock. However, since the change of this resistivity is relatively small in a small range, it is more convenient to detect with a detection range of a certain length during monitoring. Therefore, in this embodiment, the B distance is set to 4m, and the length of L1 is greater than 4m.

[0071] Step S5: Draw a resistivity curve according to the measured resistivity value ρs, interpret the obtained resistivity distribution image, and obtain the accurate distribution position of the water body by analyzing the conductivity difference between different media. ;

[0072] Step S6: Draw a geological structure map based on the resistivity curve through corresponding software, and interpret the image together with the geological radar image to determine the location and range of the water-wading structure in the rock layer near the tunnel working face.

[0073] By combining the judgment results of adverse geological areas with the specific location of water-related geological areas and the interpretation of the forecast of water-related range, the distribution location and range of water-related areas can be accurately determined, so that grouting can be accurately carried out in water-related areas during construction to prevent water-related areas from affecting the construction progress.

[0074] like Figure 7 As shown in the figure, in step three of the geological prediction process, since the detector needs to be successfully installed in the borehole, the aperture of the borehole should be slightly larger than the detector. Since the appearance of the detector is usually cylindrical, when the detector is installed in the borehole, the detector and the borehole are in point contact; and the common coupling between the detector and the borehole adopts the method of evenly applying butter on the outer wall of the detector. However, the density of butter is far different from that of rock, and as the detection process proceeds, the heat of the detector itself will cause the butter to melt, thereby causing the detector to separate from the borehole wall, increasing the error of the detector detection result.

[0075] like Figure 4 As shown, a detector coupling device of a tunnel geological advance prediction method of the present 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 and the detector 1 are relatively fixedly arranged, and an expandable annular deformation layer 4 is arranged on the periphery of the coupling wall 2. When the detector 1 is placed in a predetermined position in the borehole, a coupling liquid with a density close to that of the rock is injected into the coupling wall 2, and the deformation layer 4 expands outward and presses against the hole wall 8.

[0076] Annular sealing installation grooves 3 are provided at both ends of the circumferential surface of the coupling wall 2, and the two ends of the deformation layer 4 are respectively sealed and fixedly installed in the two sealing installation grooves 3. The sealing installation method of the deformation layer 4 can be selected to use a sealing adhesive to seal the contours of 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 close to the coupling wall 2 are sealed and connected with sealing rings 9, and the width of the sealing ring 9 is slightly larger than the width of the installation groove 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 provided at the center of the circumference of the coupling wall 2, and a plurality of injection holes 6 are provided on one end of the coupling wall 2. The plurality of injection holes 6 are evenly distributed in a circular array at one end of the coupling wall 2, and each injection hole 6 is connected to the injection groove 7. One end of each injection hole 6 away from the injection groove 7 is sealed and connected to a coupling liquid pipeline 10, and the other end of the coupling liquid pipeline 10 is connected to a pressurizing device, and the pressurizing device can inject coupling liquid into the injection groove 7 through the injection hole 6 and the coupling liquid pipeline 10. An annular gap 5 is provided 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 process of installing the detector 1 and the coupling device into the borehole, the deformable layer 4 is in point contact with the borehole wall 8 .

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

[0079] Common rock density ranges from 2.5 g / cm3 to 3 g / cm3. Therefore, in this embodiment, polytetrafluoroethylene with similar density is selected as the material of the deformation layer 4, and the injected liquid is a potassium nitrate solution with similar density. The coupling wall 2 is made of an alloy material with similar density and stable chemical properties and is cast in one piece, so that the conduction effect of the deformation layer 4, the coupling liquid, and the coupling wall 2 on the vibration wave is as close as possible to the conduction effect of the rock on the vibration wave, thereby further reducing the error of the detection process of the detector 1 and ensuring the accuracy of the detection result of the detector 1.

[0080] The above are preferred embodiments of the present invention. It should be pointed out that a person skilled in the art may make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the protection scope of the present invention.

Claims

1. A more accurate tunnel geological advance prediction method, characterized by: The geological prediction process includes the following steps: Step 1: Conduct preliminary exploration of the tunnel geology to understand the integrity of the rock mass at the tunnel face; Step 2: Arrange the boreholes according to the integrity of the surrounding rock of the face, and set an excitation point around each of the boreholes; Step 3: Arrange the detector strings according to the number of boreholes, each detector includes at least three detector units, and after each detector string is installed in the borehole, each detector unit is coupled to the borehole wall through the coupling structure of each detector unit; Step 4: Connect each detector to the TGS host at one end close to the borehole; 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 carried on the side of the hammer head of the SGD-SHC hammer source synchronization system excites each excitation point in turn, generating elastic wave signals on the surrounding rock of the tunnel face, and the detector string can collect the elastic wave signals; Step 7: Move the detector string multiple times along the borehole diameter from the inside to the outside at equal intervals, so that the detector string sequentially collects 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 tunnel face received at each position.

2. A more accurate tunnel geology advance prediction method according to claim 1, characterized in that: Step 8: Draw a time-depth curve based on the collected data; Step 9: Calculate the elastic wave travel distance ΔL of each data according to the position coordinates of the excitation point and the position coordinates of the detector string, and obtain the comprehensive wave velocity V1 of the rock mass at this distance according to V1=2×ΔL / t0. After obtaining the wave velocity of all collected data, perform inversion to obtain the wave velocity-depth curve; Step 10: Process the velocity-depth curve data through the processing software in the TGS host to obtain the longitudinal wave velocity curve, and use this curve to continuously correct the initial velocity model. Finally, according to the empirical correction formula of the velocity, the comprehensive velocity of the surrounding rock in front of the tunnel face is calculated and a parameter map is formed; Step 11: Based on the comprehensive velocity of the surrounding rock in front of the tunnel face, the processing software in the TGS host generates a corresponding map, interprets the map, identifies the geological structure within a certain range in front of the tunnel face, and detects adverse geological features.

3. A more accurate tunnel geology advance prediction method according to claim 1, characterized in that: The process of judging adverse geological areas includes the following steps: Step A: Detect the geological environment of different tunnels in different regions and conduct preliminary exploration of the tunnel geology to obtain the integrity of the rock mass at the tunnel face; Step B: Select the detection method according to the integrity of the rock mass at the tunnel face. If the tunnel face integrity is high, the continuous detection method is used; if the tunnel face integrity is low, the point detection method is used; Step C: Arrange a survey line on the tunnel face according to the selected detection method, and set a trigger point at a distance A along the survey line; Step D: Arrange the receiver and the radar instrument, and connect the receiver and the radar instrument wirelessly; Step E: Move the geological radar antenna from one end of the survey line to the other end of the survey line, and each time it passes a trigger point, fit the radar antenna on the arranged survey line, control the radar to generate high-frequency narrow pulse electromagnetic waves, and transmit the high-frequency narrow pulse electromagnetic waves to the unknown area of ​​the face through the radar antenna. The receiver can detect the reflection signal or direct transmission signal derived from the high-frequency narrow pulse electromagnetic waves in the rock layer, amplify and digitize them, and store them on a digital tape recorder for data processing and display; Step F: performing data cleaning and screening, data interpolation and resampling on the reflected signal or direct transmission signal stored in the digital tape recorder of the receiver, so that the collected data can be presented in a graphical form through corresponding software; Step G: Based on the atlas, it can be effectively determined whether the unfavorable geological area in front of the face is a hidden fracture zone or a water-related geology.

4. A more accurate tunnel geology advance prediction method according to claim 1, characterized in that: The specific location of the water-related geological area and the forecast process of the water-related scope include; Step S1: Detect the geological environment of different tunnels in different regions, and conduct preliminary exploration of the tunnel geology to understand the various geological conditions of the surrounding rock of the tunnel face; Step S2: power supply electrodes B1, B2, and B3 are arranged at a certain interval behind the tunnel face along the tunnel face width direction, the power supply electrodes B1, B2, and B3 supply power to the ground, and a fixed electrode A is arranged on a side of the power supply electrode B3 away from the power supply electrode B3 along the tunnel face width direction; Step S3: two movable measuring electrodes M and N are arranged between the fixed electrode A and the power supply electrode B3, the fixed electrode A, the measuring electrodes M and N, and the power supply electrodes B1, B2, and B3 are all located on the same straight line, the initial position of the measuring electrodes M and N is located on the side of the power supply electrode B3 close to the fixed electrode A, and the fixed electrode A is connected to the receiving device by wire or wirelessly; Step S4: Move the mobile electrodes M and N along the connecting line between the fixed electrode A and the power supply electrode B3 from the power supply electrode B3 to the fixed electrode A, and drive the two measuring electrodes M and N into the ground every time they move a distance B. 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, and store the calculated resistivity values ​​ρs on a digital tape recorder for data processing and display; Step S5: drawing a resistivity curve diagram according to the measured resistivity value ρs; Step S6: Draw a geological structure map based on the resistivity curve using corresponding software to determine the location and range of the water-related structure in the rock layer.

5. A more accurate tunnel geology advance prediction method according to claim 1, characterized in that: When the geological forecast shows adverse geological features in the forecast of the tectonic structure within a certain range in front of the tunnel face, it is necessary to make an adverse geological area judgment and an adverse geological category judgment. If the interpretation of the combined geological forecast results and the adverse geological area judgment results indicates that the adverse geology of the 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 the area. If the interpretation of the combined geological forecast results and the adverse geological area judgment results indicates that the adverse geology of the geological structure in front of the tunnel face is a water-related area, it is necessary to forecast the specific location and water-related range of the water-related geological area to obtain the distribution location and water-related range of the water-related area.

6. The detector coupling device of a more accurate tunnel geology advance prediction method according to claim 1 is characterized in that: The invention comprises a detector (1), wherein the outer coaxial sleeve of the detector (1) is provided with an annular coupling wall (2), and the outer coaxial sleeve of the coupling wall (2) is provided with an expandable annular deformation layer (4).

7. The detector coupling device of the method for improving the accuracy of tunnel geological advance prediction according to claim 6 is characterized in that: An annular injection groove (7) is provided at the center of the peripheral surface of the coupling wall (2), a plurality of injection holes (6) are provided on one end of the coupling wall (2), each of the injection holes (6) is connected to the injection groove (7), an annular gap (5) is provided between the coupling wall (2) and the deformation layer (4), and the annular gap (5) is connected to the injection groove (7).

8. The detector coupling device of the method for improving the accuracy of tunnel geological advance prediction according to claim 6 is characterized in that: Annular sealing installation grooves (3) are provided at both ends of the circumferential surface of the annular coupling wall (2), and the two ends of the deformation layer (4) are sealed and fixed in the two installation grooves (3) along the contour.

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