Tunnel boring machine controlled source seismic wave advance detection device and method

Abstract

The present invention provides a device and method for advance detection of seismic waves using a controllable seismic source for a tunnel boring machine. The device comprises: electromagnetic controllable seismic source assemblies arranged on both sides of a working platform of the tunnel boring machine; the electromagnetic controllable seismic source assemblies comprise a telescopic mandrel, a counterweight housing, an airbag, a bracket, a first base and a second base, wherein the telescopic mandrel is fixed to the side of the counterweight housing facing the rock wall; the counterweight housing and the airbag are both fixed to the first base, and the airbag is located on the side of the counterweight housing away from the telescopic mandrel, and the first base is fixedly connected to the second base via the bracket; the present invention makes full use of the space on both sides of a main control room of the tunnel boring machine to arrange the electromagnetic controllable seismic source assemblies, realizes beam forming and reverse time migration imaging methods, improves the signal-to-noise ratio of seismic records and increases imaging accuracy by beam focusing, and makes up for the deficiency of high energy but unfocused controllable seismic source detection.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel advance detection, and in particular to a device and method for advance detection of seismic waves of a tunnel boring machine with a controlled source. Background Art

[0002] The statements in this section merely provide background art related to the present invention and do not necessarily constitute prior art.

[0003] Tunnel construction using roadheaders (TBMs) can easily lead to risks such as water and mud inrush when encountering unfavorable geology, seriously threatening construction safety. Seismic wave detection, a commonly used advance prediction method, plays a crucial role in TBM-constructed tunneling. However, as tunnel construction expands into complex terrain, construction faces increasingly severe and complex geological conditions, further increasing the difficulty of seismic wave exploration.

[0004] The inventors have discovered that under extremely complex geological conditions, the traditional seismic wave advance detection method has certain limitations when used in tunnels constructed by roadheaders, including:

[0005] (1) The traditional artificial hammer seismic excitation method has weak excitation energy and the signal propagation distance is short due to manpower limitations. While the excitation energy of the mounted hydraulic and pneumatic seismic sources has been improved, it is still difficult to meet the demand for long-distance early detection of adverse geological conditions under extremely complex geological conditions. Moreover, in the tunnel environment constructed by the tunnel boring machine with severe noise, the effective reflection at a long distance is easily submerged and difficult to distinguish in the seismic record.

[0006] (2) The traditional active source detection method uses a single strong energy to excite the signal, which may cause certain safety hazards when the surrounding rock is broken;

[0007] (3) Tunnel advance prediction often uses a fixed-position seismic source for excitation, which will cause each excitation signal to spread in the form of a spherical wave. The effective energy transmitted in front of the tunnel face accounts for a small proportion, and the detection and imaging effects are not ideal. Summary of the Invention

[0008] In order to address the shortcomings of the existing technology, the present invention provides a device and method for advance detection of seismic waves using a controlled source of a tunnel boring machine. The device makes full use of the space on both sides of the tunnel boring machine's main control room to arrange electromagnetic controlled source components, realizes high-precision beam forming and reverse time migration imaging, and improves the signal-to-noise ratio of seismic records and increases imaging accuracy through beam focusing, thereby compensating for the deficiency of controlled source detection that has strong energy but is not focused.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A first aspect of the present invention provides a device for advanced detection of seismic waves with a controllable source for a tunnel boring machine.

[0011] A tunnel boring machine vibroseis seismic wave advance detection device comprises: electromagnetic vibroseis assemblies arranged on both sides of a tunnel boring machine working platform;

[0012] The electromagnetic vibrator assembly includes a telescopic mandrel, a counterweight housing, an airbag, a bracket, a first base and a second base. The telescopic mandrel is fixed to the side of the counterweight housing facing the rock wall.

[0013] The counterweight shell and the airbag are both fixed to the first base, and the airbag is located on the side of the counterweight shell away from the telescopic top rod. The first base is fixedly connected to the second base through a bracket, and the second base is used to connect to the working platform of the tunnel boring machine.

[0014] As an optional implementation of the first aspect of the present invention, it further includes an inflation device fixed on the second base, and the inflation device is connected to the airbag.

[0015] As an optional implementation of the first aspect of the present invention, the present invention further includes a three-component sensor arranged on the tunnel rock wall between the cutterhead and the electromagnetic controllable vibrator assembly.

[0016] As a further limitation of the first aspect of the present invention, the three-component sensors on both sides of the roadheader body are symmetrically arranged along the central axis of the roadheader.

[0017] As an optional implementation of the first aspect of the present invention, at least one electromagnetic controllable vibrator assembly is arranged on each side of the tunnel boring machine working platform, and the electromagnetic controllable vibrator assemblies on both sides are symmetrically arranged along the central axis of the counterweight shell.

[0018] As an optional implementation of the first aspect of the present invention, the main control room is fixed on the working platform of the tunnel boring machine, and the electromagnetic controllable vibrator components are located on both sides of the main control room.

[0019] A second aspect of the present invention provides an operating method of a vibroseis seismic wave advance detection device for a tunnel boring machine.

[0020] An operating method of a tunnel boring machine vibroseis seismic wave advance detection device, using the tunnel boring machine vibroseis seismic wave advance detection device according to the first aspect of the present invention, comprises the following steps:

[0021] When detection begins, the electromagnetic vibrator assemblies on both sides of the roadheader's working platform are activated, the telescopic push rods of the electromagnetic vibrator assemblies extend and contact the rock wall, and at the same time, the airbags of the electromagnetic vibrator assemblies are inflated through the inflation device, so that the electromagnetic vibrator assemblies can press against the rock wall;

[0022] The time-frequency information and output information of the electromagnetic controllable vibrator assembly are configured. After the electromagnetic controllable vibrator assembly is started, the dynamic coil inside the vibrator controls the counterweight shell to vibrate, thereby stimulating seismic signals.

[0023] A third aspect of the present invention provides a method for advance detection of seismic waves using a controlled source of a tunnel boring machine, using the device for advance detection of seismic waves using a controlled source of a tunnel boring machine described in the first aspect, comprising the following steps:

[0024] Through the delayed excitation of each electromagnetic vibrator assembly, the wavefront excited by each source in the form of a spherical wave is synthesized into a wave number surface, and the propagation angle of the wavefront is adjusted by different delay lengths;

[0025] The three-component geophone receives the seismic records, and the vibroseis seismic data is interferometrically processed by cross-correlation to obtain the velocity of the direct wave. A homogeneous initial velocity model is then created based on the velocity results.

[0026] Cut off the direct wave of the interferometric seismic record;

[0027] Seismic records are excited at the source position of the obtained initial velocity model to obtain the forward wave field; interferometric seismic records with the direct wave actually obtained and cut off are applied in reverse time at the three-component geophone position to obtain the reverse wave field;

[0028] The two wave fields are correlated and superimposed to obtain the reverse time migration imaging result based on beamforming.

[0029] As an optional implementation method of the third aspect of the present invention, when the forward propagation angle is θ, the excitation delay between each electromagnetic controllable vibrator assembly includes: t = xsinθ / v, wherein t is the delayed excitation time of the current electromagnetic controllable vibrator phase assembly with respect to the previous electromagnetic controllable vibrator phase assembly, x is the source spacing, v is the surrounding rock wave velocity, θ is the wavefront propagation angle, the delayed excitation time t0 of the first controllable vibrator is 0s, the delayed excitation time of the nth controllable vibrator is

[0030] A fourth aspect of the present invention provides a tunnel boring machine, comprising the tunnel boring machine vibroseis seismic wave advance detection device according to the first aspect of the present invention.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention innovatively proposes a tunnel boring machine controllable source seismic wave advance detection device. The electromagnetic controllable source stimulates seismic signals by pressing against the rock wall. By utilizing the characteristics of continuous excitation energy accumulation and controllable seismic signals, the device improves the ability to identify weak long-distance reflection signals while ensuring that the detection process does not damage the rock wall.

[0033] 2. The present invention innovatively proposes a method for mounting an electromagnetic controllable vibrator detection device, which fully utilizes the larger space on both sides of the tunnel boring machine's main control room and arranges multiple electromagnetic controllable vibrator components along the tunnel axis near the rock wall on both sides of the tunnel boring machine, further enriching the arrangement of vibrator sources in tunnels constructed by tunnel boring machines.

[0034] 3. The present invention innovatively proposes a tunnel beamforming method for a roadheader and its reverse time migration imaging. By utilizing multiple controllable seismic sources arranged on both sides of the main control room and the high precision of the controllable seismic sources in controlling signals, it is possible to achieve enhanced focusing of the forward propagation of seismic waves, and utilize reverse time migration imaging to obtain more accurate geological structure imaging results.

[0035] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0037] Figure 1 A top view of the device for advanced detection of seismic waves using a vibrator for a tunnel boring machine provided in Example 1 of the present invention;

[0038] Figure 2 A side view of the device for advanced detection of seismic waves using a vibrator for a tunnel boring machine provided in Example 1 of the present invention;

[0039] Figure 3 A front view of the device for advanced detection of seismic waves using a vibrator for a tunnel boring machine provided in Example 1 of the present invention;

[0040] Figure 4 A schematic diagram of the components of a vibroseis seismic wave advance detection device for a tunnel boring machine provided in Example 1 of the present invention;

[0041] Figure 5 Schematic diagram of the beamforming method provided in Example 3 of the present invention;

[0042] Figure 6 A schematic diagram of obtaining the wave velocity of a direct wave provided in Example 3 of the present invention;

[0043] Among them, 1. Three-component sensor; 2. Tunnel boring machine working platform; 3. Electromagnetic controllable seismic source assembly; 4. Main control room; 5. Telescopic jack; 6. Counterweight shell; 7. Airbag; 8. Bracket; 9. Second base; 10. Inflatable device; 11. Rock wall; 12. Wavefront; 13. Beam surface; 14. First base. DETAILED DESCRIPTION

[0044] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0045] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0046] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0047] Example 1:

[0048] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, embodiment 1 of the present invention provides a tunnel boring machine vibroseis seismic wave advance detection device, comprising: electromagnetic vibroseis assemblies 3 arranged on both sides of a tunnel boring machine working platform 2 (one is arranged on each side as an example);

[0049] The electromagnetic vibrator assembly 3 includes a telescopic mandrel 5, a counterweight housing 6, an airbag 7, a bracket 8, a first base 14, and a second base 9. The telescopic mandrel 5 is fixed to the side of the counterweight housing 6 facing the rock wall 11.

[0050] The counterweight shell 6 and the airbag 7 are both fixed to the first base 14, and the airbag 7 is located on the side of the counterweight shell 6 away from the telescopic top rod 5. The first base 14 is fixedly connected to the second base 9 through the bracket 8, and the second base 9 is used to connect to the tunnel boring machine working platform 2.

[0051] The telescopic top rod 5 in this embodiment can be an electric telescopic rod, or a hydraulic or pneumatic pressure controlled telescopic rod. Those skilled in the art can choose according to specific working conditions, which will not be described here.

[0052] In this embodiment, the bracket 8 can be a hollow support frame (which can save costs) or a support plate (with higher stability). Those skilled in the art can choose according to specific working conditions, which will not be described here.

[0053] In this embodiment, an inflation device 10 is further included that is fixed on the second base 9. The inflation device 10 is connected to the airbag 7. In this embodiment, an air pump is preferably used as the inflation device 10. It can be understood that in some other implementations, the gas storage device can also be used to deflate the gas, such as using a gas cylinder, etc. Those skilled in the art can make a choice based on the specific working conditions, which will not be elaborated here.

[0054] In this embodiment, a three-component sensor 1 is further included, which is arranged on the tunnel rock wall between the cutterhead and the electromagnetic vibrator assembly 3 .

[0055] In this embodiment, the three-component sensors 1 on both sides of the tunnel boring machine body are symmetrically arranged along the central axis of the tunnel boring machine.

[0056] It can be understood that in some other implementations, multiple electromagnetic controllable vibrator assemblies 3 are arranged on each side of the tunnel boring machine working platform 2, and the electromagnetic controllable vibrator assemblies 3 on both sides are symmetrically arranged along the central axis of the counterweight shell 6.

[0057] In this embodiment, the main control room 4 is fixed on the working platform 2 of the roadheader, and the electromagnetic controllable vibrator components 3 are located on both sides of the main control room 4 .

[0058] Example 2:

[0059] Embodiment 2 of the present invention provides an operating method of the vibroseis seismic wave advance detection device for a tunnel boring machine according to embodiment 1, comprising the following steps:

[0060] S1: When detection begins, the electromagnetic vibrator assemblies 3 on both sides of the roadheader working platform 2 are activated. The telescopic push rods 5 of the electromagnetic vibrator assemblies 3 extend and contact the rock wall 11. At the same time, the airbags 7 of the vibrator 3 are inflated by the inflation device 10, so that the front section of the vibrator can press against the rock wall 11 and act as a buffer when the vibrator is working.

[0061] S2: In the main control room 4, the time-frequency information and output information of the electromagnetic controllable vibrator 3 are set to achieve the purpose of knowing the time-frequency information of the earthquake record and accurately controlling the delayed emission of multiple electromagnetic controllable vibrators; after the electromagnetic controllable vibrator assembly 3 is started, the dynamic coil control counterweight shell 6 inside the electromagnetic controllable vibrator assembly 3 vibrates to stimulate the earthquake signal.

[0062] Example 3:

[0063] Since the space on both sides of the main control room 4 on the working platform 2 of the tunnel boring machine in the axial direction of the tunnel is relatively large, the number of electromagnetic controllable source components 3 that can be placed and operated is sufficient, so that the beam forming method can be implemented. In view of this, this embodiment provides a tunnel boring machine controllable source seismic wave advance detection method, such as Figure 5 As shown, the following process is included:

[0064] S1: Through the delayed excitation of each electromagnetic vibrator assembly 3, the wavefront 12 excited by each source in the form of a spherical wave can be synthesized into a wave number plane 13. By varying the delay length, the propagation angle θ of the wavefront 13 can be adjusted. The propagation angle θ of the beam plane 13 is determined by the detection requirements. When the forward propagation angle is θ, the excitation delay between each electromagnetic vibrator assembly 3 is calculated as follows:

[0065]

[0066] Wherein, t is the delayed excitation time of the current electromagnetic vibrator assembly 3 relative to the previous electromagnetic vibrator assembly 3, x is the focal distance, v is the surrounding rock wave velocity, and θ is the wavefront propagation angle; the delayed excitation time of the first electromagnetic vibrator assembly 3 is t0=0s, and the delayed excitation time of the nth electromagnetic vibrator assembly 3 is

[0067] S2: The three-component geophone 1 located in front of the electromagnetic vibrator assembly 3 receives the seismic record (the three-component geophone 1 is located between the cutterhead and the vibrator 3. The specific location does not need to be fixed, as long as it is arranged in groups along the axial direction of the tunnel). The vibrator seismic data is subjected to interference processing by cross-correlation to analyze and obtain the direct wave velocity (the direct wave velocity v = x / t is calculated by the slope of the direct wave component in the seismic record, where v is the wave velocity, x is the geophone array length, and t is the delayed excitation time of the current electromagnetic vibrator assembly 3 relative to the previous electromagnetic vibrator assembly 3). Figure 6 shown);

[0068]

[0069] Where f(t0) is the seismic record, g(t0) is the leader sensor record, t0 is the integral quantity used for full-time integration, and R(t) is the interferometric seismic record generated by cross-correlation.

[0070] In this embodiment, a homogeneous initial velocity model is created based on the wave velocity results (after obtaining the wave velocity v of the direct wave, this value is assigned to the formation. This is achieved by creating a matrix whose length, width, and height dimensions ("number of grids * set grid size") are consistent with the actual formation. The values ​​in the matrix represent the formation wave velocity, which is the direct wave velocity).

[0071] S3: remove the direct wave of the interferometric seismic record;

[0072] S4: Seismic records are excited at the source location of the obtained initial velocity model (here, autocorrelation wavelet records are excited) to obtain the forward wavefield; interferometric seismic records that actually obtain and cut off the direct wave are applied in reverse time at the detector location to obtain the reverse wavefield. The two wavefields are correlated and superimposed to obtain the reverse time migration imaging result based on beamforming.

[0073] Example 4:

[0074] Embodiment 4 of the present invention provides a tunnel boring machine, comprising the tunnel boring machine vibroseis seismic wave advance detection device described in Embodiment 1 of the present invention.

[0075] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for advanced detection of seismic waves using a controlled source of a tunnel boring machine, characterized in that: The following processes are included: Through the delayed excitation of each electromagnetic vibrator assembly, the wavefront excited by each source in the form of a spherical wave is synthesized into a wave number surface, and the propagation angle of the wavefront is adjusted by different delay lengths; When the forward propagation angle is When , the excitation delay between each electromagnetic vibrator assembly is calculated as follows: in, is the delayed excitation time of the current electromagnetic vibrator assembly relative to the previous electromagnetic vibrator assembly, is the focal distance, is the surrounding rock wave velocity, is the wavefront propagation angle, the delayed excitation time of the first vibrator , No. Delayed excitation time of a vibrator ; The three-component geophone receives the seismic records, and the vibroseis seismic data is interferometrically processed by cross-correlation to obtain the velocity of the direct wave. A homogeneous initial velocity model is then created based on the velocity results. Cut off the direct wave of the interferometric seismic record; Seismic records are excited at the source position of the obtained initial velocity model to obtain the forward wave field; interferometric seismic records with the direct wave actually obtained and cut off are applied in reverse time at the three-component geophone position to obtain the reverse wave field; The two wave fields are correlated and superimposed to obtain the reverse time migration imaging result based on beamforming; A tunnel boring machine vibroseis seismic wave advance detection device includes: electromagnetic vibroseis assemblies arranged on both sides of the tunnel boring machine working platform, the electromagnetic vibroseis assemblies including a telescopic mandrel, a counterweight housing, an airbag, a bracket, a first base, and a second base, the telescopic mandrel being fixed to the side of the counterweight housing facing the rock wall; The counterweight shell and the airbag are both fixed to the first base, and the airbag is located on the side of the counterweight shell away from the telescopic top rod. The first base is fixedly connected to the second base through a bracket.

2. The method for advanced detection of seismic waves using a controlled source of a tunnel boring machine according to claim 1, wherein: It also includes an inflation device fixed on the second base, and the inflation device is communicated with the airbag.

3. The method for advanced detection of seismic waves using a controlled source of a tunnel boring machine according to claim 1, wherein: The invention also includes a three-component sensor arranged on the tunnel rock wall between the cutter head and the electromagnetic vibrator assembly.

4. The method for advanced detection of seismic waves using a controlled source of a tunnel boring machine according to claim 3, wherein: The three-component sensors on both sides of the tunnel boring machine body are arranged symmetrically along the central axis of the tunnel boring machine.

5. The method for advanced detection of seismic waves using a controlled source of a tunnel boring machine according to claim 1, wherein: At least one electromagnetic vibrator assembly is arranged on each side of the tunnel boring machine working platform, and the electromagnetic vibrator assemblies on both sides are symmetrically arranged along the central axis of the counterweight shell.

6. The method for advanced detection of seismic waves using a controlled source of a tunnel boring machine according to claim 1, wherein: The main control room is fixed on the working platform of the tunnel boring machine, and the electromagnetic controllable vibrator components are located on both sides of the main control room.

7. An operating method for a detection device used in the method for advanced detection of seismic waves using a vibrator for a tunnel boring machine according to any one of claims 1 to 6, characterized in that: The following processes are included: When detection begins, the electromagnetic vibrator assemblies on both sides of the roadheader's working platform are activated, the telescopic push rods of the electromagnetic vibrator assemblies extend and contact the rock wall, and at the same time, the airbags of the electromagnetic vibrator assemblies are inflated through the inflation device, so that the electromagnetic vibrator assemblies can press against the rock wall; The time-frequency information and output information of the electromagnetic controllable vibrator assembly are configured. After the electromagnetic controllable vibrator assembly is started, the dynamic coil inside the vibrator controls the counterweight shell to vibrate, thereby stimulating seismic signals.

8. A tunnel boring machine, characterized in that: Used to implement the tunnel boring machine controlled source seismic wave advance detection method as described in any one of claims 1-6.

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