A method and system for continuous detection of seismic waves in a tunnel constructed by a double-line TBM

Abstract

The present application relates to the fields of tunnel engineering and engineering geophysical prospecting technology, and discloses a method and system for continuous seismic wave detection of double-line TBM construction tunnels, which comprises the following steps: laying an observation system and collecting data with a fixed transmitting-receiving distance; continuously collecting data, collecting data when the first tunnel is excavated, continuously collecting data as the cutter head excavates, and continuously collecting no less than a set number of multi-source multi-wave field data in a single test; processing refraction wave data to obtain the continuous velocity profile of the area to be excavated in the second tunnel according to the obtained velocity distribution information; interpreting refraction wave data according to the obtained continuous transverse velocity profile of the area to be excavated in the second tunnel, combining the geological information and structural distribution of the excavated tunnel section of the first tunnel, and realizing geological interpretation of geophysical data; and comprehensively detecting the adverse geological distribution perpendicular to the line direction through seismic multi-wave field multi-view. Through the present application, comprehensive detection of seismic wave method multi-wave field, multi-mode and multi-view can be realized.

Description

Technical Field

[0001] This invention relates to the fields of tunnel engineering and engineering geophysical exploration, specifically a method and system for continuous seismic wave detection in twin-track TBM construction tunnels. Background Technology

[0002] During tunnel construction, accurate advance geological forecasting of the geological conditions and potential geological hazards ahead of the tunnel face plays a crucial role in the normal construction and successful breakthrough of the tunnel. Currently, the seismic wave reflection method is the main method for advance detection of tunnels in TBM construction. Based on physical property information such as density and velocity, it has achieved certain results in detecting structural and structural aspects. However, the seismic wave reflection method is limited by the high-mechanical construction environment of TBMs, and its detection efficiency and accuracy still have considerable room for improvement. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for continuous seismic wave detection in dual-track TBM construction tunnels, comprising the following steps:

[0004] Step 1: Deploy the observation system using an 8-channel seismic detection device, with 6 channels for data acquisition and 2 channels for acquiring the TBM's natural vibration signals; trigger detectors are fixed to the TBM cutterhead for recording the excitation natural vibration signals; receiving detectors are arranged in a straight line on the same side wall and coupled to the surrounding rock of the side wall through hydraulic struts; the offset distance is selected according to the distance between the preceding and following tunnels, and data acquisition is performed using a fixed transmit / receive distance.

[0005] Step 2, continuous data acquisition: Data acquisition is carried out during the initial tunnel excavation and continuous data acquisition is carried out as the cutterhead advances. A single test continuously acquires no less than a set number of multi-source multi-wave field data, including the fuselage self-vibration signal, direct wave signal, reflected wave signal and refracted wave signal.

[0006] Step 3: Refracted wave data processing. Refracted wave signals are extracted from the collected multi-source multi-wave field data. The multi-source multi-wave field data with a set number of sets are combined into single-shot multi-wave field data. Valid refracted wave signals are obtained from the single-shot multi-wave field data and inverted to obtain velocity distribution information within a set range for the preceding and subsequent tunnels. Based on the obtained velocity distribution information, a continuous velocity profile of the area to be excavated in the subsequent tunnel is obtained.

[0007] Step 4: Interpretation of refracted wave data. Based on the obtained continuous transverse velocity profile of the area to be excavated in the subsequent tunnel, combined with the geological information and structural distribution of the excavated sections of the preceding tunnel, the geological interpretation of the geophysical data is achieved.

[0008] Step 5: Comprehensive multi-wave field and multi-view seismic detection. Based on the detection results obtained from the preliminary tunnel sidewall detection, and using the velocity profile obtained from the lateral detection as the initial model, the distribution of adverse geological conditions perpendicular to the tunnel line is obtained through the forward seismic wave reflection method in front of the tunnel face.

[0009] Furthermore, the method for coupling the detector to the structure includes:

[0010] S11, the trigger detector is fixed near the cutterhead inside the shield body. A wideband, low-sensitivity detector is selected to reduce mechanical noise and false triggering. The trigger detector is mainly used for the acquisition and prediction of vibration signals during TBM tunneling and the triggering system of the equipment. In the later data processing, this part of the signal needs to be filtered out from the acquired signal.

[0011] S12, the receiver detector needs to be fixed to the TBM body. The coupling with the surrounding rock is achieved by a hydraulic strut. The detector is installed on the top of the strut. The strut is remotely controlled by the host computer. When the test starts, the strut is automatically pushed onto the surrounding rock to collect data. After the data collection is completed, the strut is automatically retracted.

[0012] Furthermore, the selection of the offset distance based on the distance between the preceding and following tunnels includes:

[0013] The offset distance is determined by the distance between the preceding and following tunnels. Based on the principle of the refraction wave method, the detection depth h and the offset distance X1 satisfy the following equation:

[0014] X1=2htan(θ c )

[0015] Where θ c Critical angle V1 represents the upper wave velocity, V2 represents the lower medium wave velocity, and the detection depth h = h1 + h2, where h1 represents the distance between the two tunnels and h2 represents the width of the rear tunnel cross-section. The offset distance X1 and the maximum shot-receiver distance X are calculated based on this. max Take 5-7 times the detection depth h, that is, 5h =<X max <= 7h.

[0016] Furthermore, the specific steps for achieving coherent superposition of TBM multi-source multi-wavefield data in step (S3) are as follows:

[0017] S31, Signal Filtering: Through processing methods such as spectrum analysis and correlation analysis, the TBM multi-source seismic wavefield data is filtered. Spectrum analysis can obtain the frequency band range of effective signals and interference. For the TBM rock-breaking source refracted wave, the effective frequency band is the mid-low frequency band. Filtering can effectively remove interference waves from the original seismic record and highlight the effective signal.

[0018] S32, Cross-correlation processing: By introducing a cross-correlation function to measure the similarity between TBM seismic wave data, a set of data f(t) is placed relative to another set of data g(t) with different quantities. The cross-correlation value h(t) is obtained by multiplying the corresponding values ​​in the two sets and then taking the product.

[0019]

[0020] In the formula is the cross-correlation operator, and * is the convolution operator.

[0021] Furthermore, the aforementioned multi-wavefield, multi-view comprehensive seismic detection, based on the detection results obtained from the prior tunnel sidewall detection and using the velocity profile obtained from the lateral detection as the initial model, uses the forward seismic wave reflection method in front of the tunnel face for advanced detection to obtain the distribution of adverse geological conditions perpendicular to the tunnel line direction, including:

[0022] S51, the seismic refraction wave detection method of the tunnel sidewall was implemented on site, and the transverse refraction wave data of the tunnel to be excavated was collected. The seismic reflection wave detection method of the tunnel face was implemented on site, and the longitudinal reflection wave data of the tunnel to be excavated was collected.

[0023] S52, transverse detection refraction wave method data processing, to obtain the transverse velocity profile of the tunnel to be excavated, and to perform subsequent tunnel cross-section geometry extraction and digitization on the velocity profile.

[0024] Based on the transverse velocity profile, an initial velocity model was constructed in S53. Data processing and inversion were then performed on the longitudinal detection (seismic wave reflection method) data to obtain the comprehensive interpretation results for the subsequent tunnel.

[0025] A continuous seismic wave detection system for a dual-track TBM construction tunnel, employing the aforementioned method for continuous seismic wave detection in a dual-track TBM construction tunnel, includes an 8-channel seismic detection device, a trigger detector, a receiving detector, and a host computer module.

[0026] The 8-channel seismic detection equipment, trigger detector, and receiver detector are respectively connected to the host computer module.

[0027] The beneficial effects of the present invention are: (1) The present invention innovates the observation method of geological exploration of TBM construction tunnel. By using the working mode of receiving the sidewall of the excavation of the cutterhead of the first tunnel, it has the following advantages compared with the existing technology: continuous exploration with the excavation of the first tunnel, the exploration length is not limited by the excavation of the subsequent tunnel, and a continuous velocity profile of the subsequent tunnel to be excavated can be formed.

[0028] (2) This invention increases the breadth and latitude of tunnel advance detection. By introducing the seismic refraction wave method, it realizes the detection target of transverse structures. Compared with the existing technology, it has the advantages of rich detection information and easy extraction of effective information. It overcomes the problem that traditional seismic wave methods are difficult to detect hidden structures along the tunnel axis.

[0029] (3) This invention improves the accuracy of geological advance detection in TBM scenarios. By comprehensively interpreting the geological information revealed by the advance tunnel, the results of the advance tunnel refraction wave detection, and the results of the subsequent tunnel seismic reflection wave detection, it realizes a comprehensive detection technology with multiple wave fields, multiple modes, and multiple fields of view. At the same time, through the convenient deployment system mounted on the TBM body, it reduces the impact of the environment on the deployment of the observation system and reduces the interference and multiple solutions caused by different sources. On-site testing is quick, simple, and efficient, improving the accuracy of adverse geological detection in subsequent tunnels. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating a method for continuous seismic wave detection in a dual-track TBM construction tunnel.

[0031] Figure 2 This is a schematic diagram of the specific structure of the hydraulic strut system;

[0032] Figure 3 This is a schematic diagram illustrating the principle of earthquake source conversion.

[0033] Figure 4 This is a schematic diagram for the comprehensive interpretation of lateral detection. Detailed Implementation

[0034] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0035] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0036] like Figure 1 As shown, a method for continuous seismic wave detection in a dual-track TBM construction tunnel includes the following steps:

[0037] Step 1: Deploy the observation system using an 8-channel seismic detection device, with 6 channels for data acquisition and 2 channels for acquiring the TBM's natural vibration signals; trigger detectors are fixed to the TBM cutterhead for recording the excitation natural vibration signals; receiving detectors are arranged in a straight line on the same side wall and coupled to the surrounding rock of the side wall through hydraulic struts; the offset distance is selected according to the distance between the preceding and following tunnels, and data acquisition is performed using a fixed transmit / receive distance.

[0038] Step 2, continuous data acquisition: Data acquisition is carried out during the initial tunnel excavation and continuous data acquisition is carried out as the cutterhead advances. A single test continuously acquires no less than a set number of multi-source multi-wave field data, including the fuselage self-vibration signal, direct wave signal, reflected wave signal and refracted wave signal.

[0039] Step 3: Refracted wave data processing. Refracted wave signals are extracted from the collected multi-source multi-wave field data. The multi-source multi-wave field data with a set number of sets are combined into single-shot multi-wave field data. Valid refracted wave signals are obtained from the single-shot multi-wave field data and inverted to obtain velocity distribution information within a set range for the preceding and subsequent tunnels. Based on the obtained velocity distribution information, a continuous velocity profile of the area to be excavated in the subsequent tunnel is obtained.

[0040] Step 4: Interpretation of refracted wave data. Based on the obtained continuous transverse velocity profile of the area to be excavated in the subsequent tunnel, combined with the geological information and structural distribution of the excavated sections of the preceding tunnel, the geological interpretation of the geophysical data is achieved.

[0041] Step 5: Comprehensive multi-wave field and multi-view seismic detection. Based on the detection results obtained from the preliminary tunnel sidewall detection, and using the velocity profile obtained from the lateral detection as the initial model, the distribution of adverse geological conditions perpendicular to the tunnel line is obtained through the forward seismic wave reflection method in front of the tunnel face.

[0042] The method for coupling the detector to the structure includes:

[0043] S11, the trigger detector is fixed near the cutterhead inside the shield body. A wideband, low-sensitivity detector is selected to reduce mechanical noise and false triggering. The trigger detector is mainly used for the acquisition and prediction of vibration signals during TBM tunneling and the triggering system of the equipment. In the later data processing, this part of the signal needs to be filtered out from the acquired signal.

[0044] S12, the receiver detector needs to be fixed to the TBM body. The coupling with the surrounding rock is achieved by a hydraulic strut. The detector is installed on the top of the strut. The strut is remotely controlled by the host computer. When the test starts, the strut is automatically pushed onto the surrounding rock to collect data. After the data collection is completed, the strut is automatically retracted.

[0045] The method of selecting the offset distance based on the distance between the preceding and following tunnels includes:

[0046] The offset distance is determined by the distance between the preceding and following tunnels. Based on the principle of the refraction wave method, the detection depth h and the offset distance X1 satisfy the following equation:

[0047] X1=2htan(θ c )

[0048] Where θ c Critical angle V1 represents the upper wave velocity, V2 represents the lower medium wave velocity, and the detection depth h = h1 + h2, where h1 represents the distance between the two tunnels and h2 represents the width of the rear tunnel cross-section. The offset distance X1 and the maximum shot-receiver distance X are calculated based on this. max Take 5-7 times the detection depth h, that is, 5h =<X max <= 7h.

[0049] The specific steps for achieving coherent superposition of TBM multi-source multi-wavefield data in step (S3) are as follows:

[0050] S31, Signal Filtering: Through processing methods such as spectrum analysis and correlation analysis, the TBM multi-source seismic wavefield data is filtered. Spectrum analysis can obtain the frequency band range of effective signals and interference. For the TBM rock-breaking source refracted wave, the effective frequency band is the mid-low frequency band. Filtering can effectively remove interference waves from the original seismic record and highlight the effective signal.

[0051] S32, Cross-correlation processing: By introducing a cross-correlation function to measure the similarity between TBM seismic wave data, a set of data f(t) is placed relative to another set of data g(t) with different quantities. The cross-correlation value h(t) is obtained by multiplying the corresponding values ​​in the two sets and then taking the product.

[0052]

[0053] In the formula is the cross-correlation operator, and * is the convolution operator.

[0054] The aforementioned multi-wavelength, multi-view comprehensive seismic detection, based on the detection results obtained from the prior tunnel sidewall detection and using the velocity profile obtained from the lateral detection as the initial model, employs the forward seismic wave reflection method in front of the tunnel face for advanced detection to obtain the distribution of adverse geological conditions perpendicular to the tunnel route, including:

[0055] S51, the seismic refraction wave detection method of the tunnel sidewall was implemented on site, and the transverse refraction wave data of the tunnel to be excavated was collected. The seismic reflection wave detection method of the tunnel face was implemented on site, and the longitudinal reflection wave data of the tunnel to be excavated was collected.

[0056] S52, transverse detection refraction wave method data processing, to obtain the transverse velocity profile of the tunnel to be excavated, and to perform subsequent tunnel cross-section geometry extraction and digitization on the velocity profile.

[0057] Based on the transverse velocity profile, an initial velocity model was constructed, and longitudinal detection (seismic wave reflection method) data processing and inversion were performed to obtain the comprehensive interpretation results of the subsequent tunnel.

[0058] A continuous seismic wave detection system for a dual-track TBM construction tunnel, employing the aforementioned method for continuous seismic wave detection in a dual-track TBM construction tunnel, includes an 8-channel seismic detection device, a trigger detector, a receiving detector, and a host computer module.

[0059] The 8-channel seismic detection equipment, trigger detector, and receiver detector are respectively connected to the host computer module.

[0060] Specifically, a method and system for continuous seismic wave detection in dual-track TBM construction tunnels includes the following steps:

[0061] (S1) Observation system deployment: The observation system deployment adopts the method of receiving the seismic signals from the cutterhead of the preceding tunnel and the sidewall. The entire prediction system is mounted on the TBM and uses an 8-channel seismic detection device. Six channels are used for receiving and acquiring data, and two channels are used for triggering and acquiring the natural vibration signals of the TBM body. The trigger detector is fixed to the cutterhead and is used for signal triggering and recording the natural vibration signals. The receiving detector is arranged in a straight line on the sidewall of the same side (adjacent to the side of the following tunnel). It is coupled with the surrounding rock of the sidewall through hydraulic struts. The appropriate offset distance is selected according to the distance between the preceding tunnel and the following tunnel. The observation system parameters remain unchanged during the test. A fixed transmit and receive distance is used to detect the geological information of a fixed mileage section of the following tunnel.

[0062] (S2) Continuous Data Acquisition: The hardware and software system is controlled in real time by a host computer. On-site testing is conducted during the normal excavation of the preceding tunnel, using fixed observation system parameters. Continuous data acquisition is performed as the cutterhead of the preceding tunnel advances, aiming to achieve continuous detection of the subsequent tunnel. Since the seismic wavefield generated by the TBM rock breaking is a multi-source, multi-wavefield seismic signal, multiple sets of data need to be continuously acquired during on-site data acquisition. Each test requires the continuous acquisition of no less than 50 sets of data, including wavefield signals such as the fuselage's natural vibration signal, direct wave signal, reflected wave signal, and refracted wave signal.

[0063] (S3) Refraction wave data processing: It is necessary to extract the refraction wave signal from the acquired multi-source multi-wave field data. In view of the problem of multi-source seismic wave field, the processing method of multi-source data coherent superposition and refraction wave field picking technology is adopted. The 50 sets of raw data are synthesized into single-shot multi-channel data, and the effective refraction wave signal is picked from the single-shot record. The picked refraction wave signal is inverted and calculated to obtain the velocity distribution information of the preceding tunnel and the subsequent tunnel within a certain range. Through the continuous testing method of excavation and exploration, the continuous velocity profile of the area to be excavated in the subsequent tunnel is obtained.

[0064] (S4) Interpretation of refracted wave data: The results obtained by the continuous detection method of receiving the sidewall of the cutterhead in the first tunnel are continuous transverse velocity profiles of the area to be excavated in the subsequent tunnel. The main reflection is the structural distribution of the subsequent tunnel along the line direction (longitudinal). Combined with the geological information and structural distribution of the excavated section of the first tunnel, the geological interpretation of the geophysical data is realized.

[0065] (S5) Comprehensive multi-wave field and multi-view seismic detection: Based on the detection results obtained from the preliminary tunnel sidewall detection (lateral detection), and using the velocity profile obtained from the lateral detection as the initial model, the distribution of adverse geological conditions perpendicular to the tunnel face (lateral detection) is obtained through the forward seismic wave reflection method at the tunnel face. By using the technical means of comprehensive detection of seismic refracted waves and seismic reflected waves, sidewalls and tunnel face, the comprehensive detection technology of multi-wave field, multi-mode and multi-view seismic detection is realized, thereby improving the accuracy of adverse geological detection.

[0066] The specific method for coupling the detector to the structure in step S1 is as follows:

[0067] (S11) The trigger detector is fixed near the cutterhead inside the shield body. A wideband, low-sensitivity detector is selected to reduce mechanical noise and false triggering. The trigger detector is mainly used for the acquisition and prediction of vibration signals during TBM tunneling and the triggering system of the equipment. In the later data processing, this part of the signal needs to be filtered out from the acquired signal.

[0068] (S12) The receiver detector needs to be fixed to the TBM body. Coupling with the surrounding rock is achieved using a hydraulic strut. The detector is mounted on the top of the strut, which is remotely controlled by a host computer. At the start of the test, the strut is automatically pushed onto the surrounding rock for data acquisition. After data acquisition is complete, the strut is automatically retracted. The specific structure of the hydraulic strut system is as follows: Figure 2 As shown:

[0069] In implementation, the hydraulic strut system includes a base device 1, which is fixed to the TBM body. The top of the base device 1 is connected to a hydraulic strut 2. The segments of the hydraulic strut 2 are connected by an interconnecting device 3. The tail section hydraulic strut 3 is connected to the transverse strut 5 by an angle device 3. The transverse strut 5 is externally connected to a rotary motor 6, which is externally connected to a rotating disc 7. The rotary motor 6 provides power, which drives the disc 7 to rotate through a bearing 8. The rotating disc 7 is externally connected to two sets of miniature hydraulic struts 9 and 10, which include a coupled drilling operation system and a detector placement system. The drilling operation system includes a hydraulic strut mother rod 9 and a daughter rod 11. The daughter rod 11 is externally connected to a drilling rig 13 and a drill bit 14. The detector placement system includes a hydraulic strut mother rod 10 and a daughter rod 12. The daughter rod 12 is externally connected to a mechanical claw drive system 15, which is externally connected to a mechanical claw 16. The mechanical claw 16 is used to automatically install and remove the detector 17.

[0070] The specific method for selecting the receiver offset in step S1 is as follows: the offset is determined by combining the distance between the preceding and following tunnels. Based on the principle of the refraction wave method of exploration, the detection depth h and the offset X1 satisfy the equation: X1=2htan(θ) c ), where θ c Critical angle V1 represents the upper wave velocity, V2 represents the lower medium wave velocity, and the detection depth h = h1 + h2, where h1 represents the distance between the two tunnels and h2 represents the width of the rear tunnel cross-section. The offset distance X1 and the maximum shot-receiver distance X are calculated based on this. max Take 5-7 times the detection depth h, that is, 5h =<X max <= 7h. The distance between receivers is not less than 5.0 meters. During the test, the observation system parameters are fixed, a fixed transmit / receive distance is used, and the detection depth is also fixed. The prediction system can detect the geological information of a fixed mileage section of the subsequent tunnel.

[0071] The specific steps for achieving coherent superposition of TBM multi-source multi-wavefield data in step S3 are as follows:

[0072] (S31) Signal filtering: The TBM multi-source seismic wave field data is filtered through spectral analysis, correlation analysis and other processing methods. The frequency band range of effective signals and interference can be obtained through spectral analysis. The effective frequency band range of the TBM rock-breaking source refracted wave is the mid-low frequency band. The filtering process can effectively remove the interference waves of the original seismic record and highlight the effective signal.

[0073] (S32) Cross-correlation processing: A cross-correlation function is introduced to measure the similarity between TBM seismic wave data. One set of data f(t) is placed relative to another set of data g(t) with different quantities. The cross-correlation value h(t) is obtained by multiplying the corresponding values ​​in the two sets and then taking the product.

[0074]

[0075] In the formula `*` represents the cross-correlation operator, and `*` represents the convolution operator. An important property of cross-correlation is that it can shorten propagation time or propagation path, as shown in the figure; from... Figure 3 This example shows that after cross-correlation calculation, the location of the seismic source has been repositioned to the location of the detector on the side closest to the seismic source.

[0076] (S33) Coherent superposition of multi-channel data: For multi-channel seismic data after cross-correlation processing, the coherent superposition of multi-source data is adopted to perform coherent superposition calculation on the 50 original data collected, so as to further remove random interference factors, strengthen the effective wavefield signal, and synthesize the 50 multi-source multi-wavefield data into single-shot multi-wavefield data.

[0077] The specific method for vertical geological interpretation in step S4 is as follows: Due to the use of a pre-excavation tunnel sidewall receiving method, the structural surfaces of the detection results are mainly distributed along the tunnel axis: a velocity profile of the entire section from the pre-excavation tunnel sidewall to the subsequent tunnel body, achieving vertical detection of adverse geological conditions in the tunnel to be excavated; during result interpretation, combined with prior geological information from the pre-excavation tunnel—including sidewall outcrops, lithology, occurrence, and existing structures—and geophysical vertical detection results, a comprehensive interpretation is performed to improve the reliability of the interpretation results, such as... Figure 4 As shown.

[0078] The specific steps for implementing the multi-wavefield, multi-view integrated seismic detection technology in step S5 are as follows:

[0079] (S51) The seismic refraction wave method of the tunnel sidewall was implemented on-site, and the transverse refraction wave data of the tunnel to be excavated was collected. The seismic reflection wave method of the tunnel face was implemented on-site, and the longitudinal reflection wave data of the tunnel to be excavated was collected.

[0080] (S52) Transverse detection refraction wave method data processing to obtain the transverse velocity profile of the tunnel to be excavated, and then perform subsequent tunnel cross-section geometry extraction and digitization on the velocity profile.

[0081] (S53) Based on the transverse velocity profile, an initial velocity model is constructed, and longitudinal detection (seismic wave reflection method) data processing and inversion are carried out to obtain the comprehensive interpretation results of the subsequent tunnel. The comprehensive results integrate the information of the seismic wave reflection method and the refraction wave method. Through the comprehensive detection technology of multi-wave field (reflected waves and refraction waves), multi-mode (a priori geological information, a priori structures, geophysical results), and multi-view (pre-tunnel sidewalls and subsequent tunnel face), the accuracy of adverse geological detection of the subsequent tunnel is improved.

[0082] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A method for continuous seismic wave detection in dual-track TBM construction tunnels, characterized in that, Includes the following steps: Step 1: Deploy the observation system using an 8-channel seismic detection device, with 6 channels for data acquisition and 2 channels for acquiring the TBM's natural vibration signals; trigger detectors are fixed to the TBM cutterhead for recording the excitation natural vibration signals; receiving detectors are arranged in a straight line on the same side wall and coupled to the surrounding rock of the side wall through hydraulic struts; the offset distance is selected according to the distance between the preceding and following tunnels, and data acquisition is performed using a fixed transmit / receive distance. Step 2, continuous data acquisition: Data acquisition is carried out during the initial tunnel excavation and continuous data acquisition is carried out as the cutterhead advances. A single test continuously acquires no less than a set number of multi-source multi-wave field data, including the fuselage self-vibration signal, direct wave signal, reflected wave signal and refracted wave signal. Step 3: Refracted wave data processing. Refracted wave signals are extracted from the collected multi-source multi-wave field data. The multi-source multi-wave field data with a set number of sets are combined into single-shot multi-wave field data. Valid refracted wave signals are obtained from the single-shot multi-wave field data and inverted to obtain velocity distribution information within a set range for the preceding and subsequent tunnels. Based on the obtained velocity distribution information, a continuous velocity profile of the area to be excavated in the subsequent tunnel is obtained. Step 4: Interpretation of refracted wave data. Based on the obtained continuous transverse velocity profile of the area to be excavated in the subsequent tunnel, combined with the geological information and structural distribution of the excavated sections of the preceding tunnel, the geological interpretation of the geophysical data is achieved. Step 5: Comprehensive multi-wave field and multi-view seismic detection. Based on the detection results obtained from the preliminary tunnel sidewall detection, and using the velocity profile obtained from the lateral detection as the initial model, the distribution of adverse geological conditions perpendicular to the tunnel line is obtained through the forward seismic wave reflection method in front of the tunnel face.

2. The method for continuous seismic wave detection in a dual-track TBM construction tunnel according to claim 1, characterized in that... The method for coupling the detector to the structure includes: S11, the trigger detector is fixed near the cutterhead inside the shield body. A wideband low-sensitivity detector is selected to reduce mechanical noise and false triggering. The trigger detector is used to collect and predict the excitation and self-vibration signal during TBM tunneling and to trigger the system. This part of the signal needs to be filtered out from the collected signal during data processing. S12, the receiver detector needs to be fixed to the TBM body. The coupling with the surrounding rock is achieved by a hydraulic strut. The detector is installed on the top of the strut. The strut is remotely controlled by the host computer. When the test starts, the strut is automatically pushed onto the surrounding rock to collect data. After the data collection is completed, the strut is automatically retracted.

3. The method for continuous seismic wave detection in a dual-track TBM construction tunnel according to claim 1, characterized in that... The method of selecting the offset distance based on the distance between the preceding and following tunnels includes: The offset is determined by the distance between the preceding and following tunnels, based on the principle of the refraction wave method for exploration, to determine the depth. and offset distance Satisfaction: in Critical angle , For upper-layer wave velocity, For the wave velocity of the lower medium, the detection depth ,in Indicates the distance between two tunnels. This represents the width of the subsequent tunnel section, which is used to calculate the offset distance. Maximum shot-receiver distance Take 5-7 times the detection depth ,Right now .

4. The method for continuous seismic wave detection in a dual-track TBM construction tunnel according to claim 1, characterized in that... The specific steps for achieving coherent superposition of multi-source, multi-wavefield data are as follows: S31, Signal Filtering: Through spectrum analysis and correlation analysis, the TBM multi-source seismic wavefield data is filtered. The effective signal and interference frequency band range can be obtained through spectrum analysis. For the TBM rock-breaking source refracted wave, the effective frequency band is in the mid-low frequency band. Filtering can effectively remove the interference waves of the original seismic record and highlight the effective signal. S32, Cross-correlation processing: By introducing a cross-correlation function, the similarity between TBM seismic wave data is measured. A set of data... Using different quantities relative to another set of data By placing the corresponding values ​​in the two groups, multiplying them, and then taking the product, we obtain the cross-correlation value. : In the formula is the cross-correlation operator, and * is the convolution operator.

5. A method for continuous seismic wave detection in a dual-track TBM construction tunnel according to claim 1, characterized in that... The aforementioned multi-wavelength, multi-view comprehensive seismic detection, based on the detection results obtained from the prior tunnel sidewall detection and using the velocity profile obtained from the lateral detection as the initial model, uses the forward seismic wave reflection method in front of the tunnel face for advanced detection to obtain the distribution of adverse geological conditions perpendicular to the tunnel line, including: S51, the seismic refraction wave detection method of the tunnel sidewall was implemented on site, and the transverse refraction wave data of the tunnel to be excavated was collected. The seismic reflection wave detection method of the tunnel face was implemented on site, and the longitudinal reflection wave data of the tunnel to be excavated was collected. S52, transverse detection refraction wave method data processing, to obtain the transverse velocity profile of the tunnel to be excavated, and to perform subsequent tunnel cross-section geometry extraction and digitization on the velocity profile. Based on the transverse velocity profile, an initial velocity model was constructed, and longitudinal detection data was processed and inverted to obtain the comprehensive interpretation results of the subsequent tunnel.

6. A continuous seismic wave detection system for dual-track TBM construction tunnels, characterized in that, The method for continuous seismic wave detection in a dual-track TBM construction tunnel according to any one of claims 1-5 includes an 8-channel seismic detection device, a trigger detector, a receiving detector, and a host computer module. The 8-channel seismic detection equipment, trigger detector, and receiver detector are respectively connected to the host computer module.

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