Disaster-causing tectonic earthquake advanced detection device and method capable of stopping drilling along with hole

Abstract

The invention discloses a disaster-causing tectonic earthquake advanced detection device and method capable of stopping drilling along with a hole, a hollow rod body is of a double-layer structure formed by an inner pipe and an outer pipe, and an annular channel between the inner pipe and the outer pipe serves as a first water injection channel; the shock absorber is installed in the inner pipe, away from the drill bit and used for containing the node type seismograph, a second water injection channel is formed in the shock absorber, and the hydraulic pressurization system is used for injecting high-pressure water into the inner pipe. When water is injected through the first water injection channel, the strong spring, the metal impact block and the piston can be reset. According to the mode of conducting seismic detection while drilling, under the condition of adapting to the drilling seismic construction environment, drilling construction is achieved, meanwhile, the capability of detecting a front disaster-causing structure is achieved, and the advantages of being long in distance, large in range and high in precision are achieved.

Description

Technical Field

[0001] The present invention relates to a detection device and an advance prediction method, in particular to an advance detection device and method for disaster-causing tectonic earthquakes with drilling stopped as the hole is drilled, belonging to the technical field of tunnel advance detection. Background Art

[0002] In tunnel excavation, it is crucial to pre-evaluate the geological conditions ahead. If excavation is carried out without clear parameters such as the orientation of the disaster-causing structure, geological disasters such as landslides, falling blocks, and water inrush are likely to occur, threatening the safe excavation of the working face. The stress distribution of the rock mass around the disaster-causing structure is uneven, which may cause rock bursts or deformation of the surrounding rock (such as compression deformation). At present, the detection method for disaster-causing structures is generally drilling first and then geophysical exploration. The main geophysical exploration method is seismic advance detection. The disadvantages of the current method are: (1) Geophysical exploration and drilling are carried out at different times, which is time-consuming and labor-intensive, affecting the production progress. (2) The seismic method is affected by factors such as the exploration distance and external noise interference, and its accuracy is relatively poor. (3) In order to compensate for the shortcomings of poor geophysical accuracy, the drilling workload needs to be increased, affecting the production progress.

[0003] Therefore, how to provide a detection device and advanced detection method that can adapt to the drilling earthquake construction environment, have the ability to detect disaster-causing structures ahead of excavation, and have long distance, large range, and high precision is an urgent need of this industry. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention provides a device and method for advance detection of disaster-causing earthquakes in disaster-causing structures by stopping drilling while drilling. It adopts the method of earthquake detection while drilling, and can detect the disaster-causing structure ahead while drilling under the condition of adapting to the drilling earthquake construction environment, and has the advantages of long distance, large range and high precision.

[0005] In order to achieve the above-mentioned object, the technical solution adopted by the present invention is: a device for advanced detection of disaster-causing tectonic earthquakes with drilling stopped, comprising a hollow rod, a shock absorber, a strong spring, a metal impact block, a piston and a hydraulic pressurization system;

[0006] The hollow rod body is formed into a double-layer structure by an inner tube and an outer tube, and a drill bit is installed at one end of the hollow rod body; the annular channel between the inner tube and the outer tube serves as a first water injection channel; and the first water injection channel is connected to the inner tube near the drill bit; the strong spring, the metal impact block and the piston are all installed in the hollow rod body, and the two ends of the strong spring are respectively connected to one end of the metal impact block and one end of the piston. When the piston is subjected to force, the strong spring will deform and drive the metal impact block to move axially along the inner tube; the shock absorber is installed in the inner tube and away from the drill bit, and is used to place a node-type seismograph The node-type seismograph is used to receive earthquake signals; a second water injection channel is provided on the shock absorber, and the hydraulic pressurization system includes a pressurizing device, one end of the pressurizing device is connected to the water source, and the other end is connected to the inner tube through the first water injection channel or the second water injection channel, and is used to inject high-pressure water into the inner tube. When water is injected through the second water injection channel, it can push the piston to move and cause the strong spring to deform and increase the elastic force, thereby driving the metal impact block to move quickly and hit the drill bit to generate seismic waves. When water is injected through the first water injection channel, the strong spring, metal impact block and piston can be reset.

[0007] Furthermore, the pressurizing device is equipped with two one-way valves, which are respectively connected to the first water injection channel and the second water injection channel, and are used to allow high-pressure water to be unidirectionally injected into the inner tube through any water injection channel as needed.

[0008] The working method of the above-mentioned device for detecting tectonic earthquakes in advance with drilling stopped is as follows:

[0009] Step 1: Drilling parameter collection: During drilling, a drilling rig is used. A downhole pressure sensor, torque and speed sensor, displacement sensor, and oil pressure sensor are installed on the rig. Each sensor is connected to the drilling rig's data monitoring system to collect speed, torque, displacement, and drilling pressure parameters during the drilling process. The wave velocity of different rock layers is determined by calculating the collected parameters to provide prior data for seismic inversion.

[0010] Step 2: Determine the initial inversion velocity model: Set a threshold value and divide the wave velocity of the rock layers at different positions in step 1 according to the threshold value. The wave velocity less than the threshold value is a low-velocity area, and the wave velocity greater than or equal to the threshold value is a high-velocity area, thereby obtaining the initial velocity model;

[0011] Step 3: Collecting seismic reflection waves: Before drilling, a node-type seismometer is installed on each drill rod, and one end of the disaster-causing earthquake advance detection device is equipped with a drill bit and the other end is connected to the drilling rig; when drilling begins, a drill rod is added every time a drill rod is drilled; in the interval between each drill rod addition, a seismic wave is excited using the disaster-causing earthquake advance detection device, and each node-type seismometer receives the seismic data of the excitation. After the excitation and drill rod addition are completed, drilling continues until the entire borehole is drilled, and seismic data corresponding to multiple seismic wave excitations are obtained;

[0012] Step 4: Data inversion for disaster-causing structure detection: Use the initial velocity model M0 to perform the first inversion on the seismic data collected when the first seismic wave was excited, and obtain the inversion result M1 of the first inversion; then use the inversion result M1 of the first inversion as the initial model for the second inversion, and use the initial model of the second inversion to perform the second inversion on the seismic data collected when the second seismic wave was excited, and obtain the inversion result of the second inversion; and so on, continuously update and iterate until the inversion of all excited seismic waves is completed. The final result is the inversion result that is closest to the real disaster-causing structure.

[0013] Furthermore, in step 1, the wave velocity of different rock layers is determined by collecting parameters and calculating, specifically:

[0014] Establish the energy index formula:

[0015] E=T·RPM / A b

[0016] Among them, E is energy index, T is torque, RPM is speed, A b is the cross-sectional area of ​​the drill bit;

[0017] The calculation formula of rock wave velocity is established based on energy index:

[0018] Vp=1500+0.5·E 0.6

[0019] Among them, Vp is the rock wave velocity.

[0020] Furthermore, the drilling rig is a mining crawler drilling rig.

[0021] Furthermore, the length of the drill rod is 2m.

[0022] Furthermore, the specific process of exciting seismic waves each time is as follows: the drill bit contacts the bottom of the borehole, the pressure device of the hydraulic pressure system is connected to the hollow rod body, and the hydraulic pressure system injects high-pressure water into the inner tube through the second water injection channel. At this time, the piston is forced to press the strong spring to deform it and increase the elastic force, while driving the metal impact block to move toward the drill bit with a continuously increasing speed until the metal impact block moves rapidly and hits the drill bit to generate seismic waves, which are transmitted to the surrounding coal rock through the drill bit; after completing one excitation, the water in the inner tube is discharged through the second water injection channel, and then water is injected into the first water injection channel. The water enters the inner tube from near the drill bit to push the metal impact block, the strong spring and the piston to reset. After completion, the water in the inner tube is discharged through the first water injection channel, completing one process of exciting seismic waves.

[0023] Furthermore, the calculation method of the travel time of the reflected wave of the disaster-causing structure in the inversion process of step 4 is:

[0024]

[0025] Among them, t is the total travel time of the reflected wave (seconds); d is the vertical distance from the tunnel face to the disaster-causing structure (m); L is the reference distance between the receiving point of the nodal seismograph and the tunnel face (meters); nL and mL are the distances of the seismic wave excitation point and the receiving point of the nodal seismograph from the tunnel face (m < n), a is the angle (dip angle) between the normal of the reflection point on the surface of the disaster-causing structure and the parallel line of the tunnel heading, Vp is the rock formation velocity (meters per second);

[0026] The core of seismic reflection wave travel time inversion is to infer the physical property parameters of the underground medium by combining the propagation time (travel time) of seismic waves in the underground medium with physical models and mathematical optimization methods; therefore, the travel time of seismic waves in the underground medium is calculated using the above formula, and the corresponding imaging result is inversely obtained.

[0027] Compared with the prior art, the present invention combines a hollow rod body, a shock absorber, a strong spring, a metal impact block, a piston and a hydraulic pressurization system, and has the following advantages:

[0028] 1. The observation system of the present invention is dynamically variable, that is, the seismic source excitation position and the receiving positions of each geophone change dynamically with drilling each time the seismic wave is excited, and the distances between the seismic source excitation position and the receiving positions of each geophone and the disaster-causing structure ahead will be closer and closer. In this way, each time the detection is updated, the seismic wave travel time will be smaller and the signal-to-noise ratio will be higher; thus effectively improving the positioning accuracy of the disaster-causing structure.

[0029] 2. Since the accuracy of seismic inversion is always limited by the initial velocity model, the detection device of the present invention can drill while drilling and collect seismic wave data at different positions, and continuously collect drilling parameters during the drilling process, and combine the existing geological data as prior data, so as to be able to more accurately determine the initial velocity model, and finally effectively ensure the accuracy of detecting and positioning the position and range of the disaster-causing structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the overall structural schematic diagram of the disaster-causing structure seismic advanced detection device of the present invention;

[0031] Figure 2 is the structural schematic diagram of the injector head in the present invention;

[0032] Figure 3 is the traditional inversion initial velocity model and the initial velocity model established during the first inversion of the present invention;

[0033] Among them, (a) is the initial velocity model of traditional inversion; (b) is the initial velocity model of the present invention;

[0034] Figure 4It is a schematic diagram of disaster-causing structure detection using data inversion according to the present invention.

[0035] In the figure: 1. drill bit, 2. metal impact block, 3. strong spring, 4. first water injection channel, 5. shock absorber, 6. second water injection channel, 7. pressurizing device. DETAILED DESCRIPTION

[0036] The present invention will be further described below.

[0037] like Figure 1 and 2 As shown, a device for detecting tectonic earthquakes that can be stopped while drilling is in progress includes a hollow rod, a shock absorber 5, a strong spring 3, a metal impact block 2, a piston, and a hydraulic pressure system.

[0038] The hollow rod body is formed into a double-layer structure by an inner tube and an outer tube, and a drill bit 1 is installed at one end of the hollow rod body; the annular channel between the inner tube and the outer tube serves as a first water injection channel 4; and the first water injection channel 4 is connected to the inner tube near the drill bit 1; the strong spring 3, the metal impact block 2 and the piston are all installed in the hollow rod body, and the two ends of the strong spring 3 are respectively connected to one end of the metal impact block 2 and one end of the piston. When the piston is subjected to force, the strong spring 3 will be deformed and then drive the metal impact block 2 to move axially along the inner tube; the shock absorber 5 is installed in the inner tube and away from the drill bit 1, and is used to place a node-type seismograph, which is used to receive earthquake signals; a second water injection channel 6 is provided on the shock absorber 5, and a hydraulic The pressurizing system includes a pressurizing device, one end of which is connected to the water source and the other end is connected to the inner tube through the first water injection channel 4 or the second water injection channel 6, and is used to inject high-pressure water into the inner tube. When water is injected through the second water injection channel 6, it can push the piston to move, causing the strong spring 3 to deform and increase the elastic force, thereby driving the metal impact block 2 to move quickly and impact the drill bit 1 to generate seismic waves. When water is injected through the first water injection channel 4, the strong spring 3, the metal impact block 2 and the piston can be reset; the pressurizing device 7 is equipped with two one-way valves, which are respectively connected to the first water injection channel 4 and the second water injection channel 6, and are used to allow high-pressure water to be injected into the inner tube in one direction through any water injection channel as needed. The above-mentioned shock absorber 5, node-type seismograph and hydraulic pressurizing system are all existing

[0039] like Figure 4 As shown, the working method of the above-mentioned device for detecting disaster-causing tectonic earthquakes in advance with drilling stopped is as follows:

[0040] Step 1: Drilling parameter collection: During drilling, a drilling rig is used. A downhole pressure sensor, torque and speed sensor, displacement sensor, and oil pressure sensor are installed on the drilling rig. Each sensor is connected to the drilling rig's data monitoring system to collect speed, torque, displacement, and drilling pressure parameters during the drilling process. The wave velocity of different rock layers is determined by calculating the collected parameters to provide prior data for seismic inversion. The wave velocity calculation is specifically as follows:

[0041] Establish the energy index formula:

[0042] E=T·RPM / Ab

[0043] Among them, E is energy index, T is torque, RPM is speed, A b is the cross-sectional area of ​​the drill bit;

[0044] The calculation formula of rock wave velocity is established based on energy index:

[0045] Vp=1500+0.5·E 0.6

[0046] Among them, Vp is the rock wave velocity.

[0047] Step 2: Determine the initial inversion velocity model: Set a threshold value, divide the wave velocity of the rock layer at different positions in step 1 according to the threshold value, the area less than the threshold value is the low-speed area, and the area greater than or equal to the threshold value is the high-speed area, and then obtain the initial velocity model; compared with the traditional inversion of a single initial velocity model for the entire region, such as Figure 3 As shown in a, a more accurate initial velocity model is Figure 3 As shown in b;

[0048] Step 3, collecting seismic reflection waves: before drilling, a shock-absorbing device is used to fix a node-type seismograph at the same position on each drill rod. The length of each drill rod is 2m, and the distance between the detection points of two adjacent node-type seismographs is 2m; one end of the disaster-causing structural earthquake advance detection device is equipped with a drill bit, and the other end is connected to the drilling rig; the drilling rig is a mining crawler drilling rig; when drilling starts, the drill rod is stopped every time a drill rod is drilled 2m in length; the disaster-causing structural earthquake advance detection device is used to excite a seismic wave in the gap between each drill rod. The specific process of exciting seismic waves each time is as follows: the drill bit 1 contacts the bottom of the borehole, and the pressure device 7 of the hydraulic pressure system is connected to the hollow rod body. The hydraulic pressure system injects high-pressure water into the inner tube through the second water injection channel 6. At this time, the piston is forced to press the strong spring 3 to make Its deformation increases the elastic force and at the same time drives the metal impact block 2 to move toward the drill bit with a continuously increasing speed until the metal impact block 2 moves rapidly and hits the drill bit 1 to generate seismic waves, which are transmitted to the surrounding coal rock through the drill bit 1; after completing one excitation, the pressure device 7 is removed to discharge the water in the inner tube through the second water injection channel 6, and then the pressure device 7 is installed to inject water into the first water injection channel 4. Water enters the inner tube from near the drill bit 1 to push the metal impact block 2, the strong spring 3 and the piston to reset. After completion, the pressure device 7 is removed to discharge the water in the inner tube through the first water injection channel 4, completing the process of exciting seismic waves; each node-type seismometer receives the seismic data of this excitation, and continues drilling after completing the excitation and the increase of the drill rod until the drilling of the entire borehole is completed, and a total of seismic data corresponding to multiple seismic wave excitations are obtained;

[0049] Step 4. Data inversion for detecting disaster-causing structures: Use the initial velocity model M0 to perform the first inversion on the seismic data collected when the seismic wave is first excited, and obtain the inversion result M1 of the first inversion. Then, take the inversion result M1 of the first inversion as the initial model of the second inversion, and use the initial model of the second inversion to perform the second inversion on the seismic data collected when the seismic wave is second excited, and obtain the inversion result of the second inversion. And so on, continuously update and iterate until the inversion of all excited seismic waves is completed. The finally obtained result is the inversion result closest to the real disaster-causing structure.

[0050] The calculation method of the travel time of the disaster-causing structure reflection wave during the inversion process in Step 4 is as follows:

[0051]

[0052] where t is the total travel time of the reflection wave (seconds); d is the vertical distance from the tunnel face to the disaster-causing structure (m); L is the reference distance between the receiving point of the nodal seismograph and the tunnel face (meters); nL and mL are the distances of the seismic wave excitation point and the receiving point of the nodal seismograph from the tunnel face (m < n), a is the angle (dip angle) between the normal of the reflection point on the surface of the disaster-causing structure and the parallel line of the tunnel heading, and Vp is the rock formation velocity (meters per second);

[0053] The core of the seismic reflection wave travel time inversion is to inversely infer the physical property parameters of the underground medium through the propagation time (travel time) of the seismic wave in the underground medium, combined with the physical model and the mathematical optimization method. Therefore, the travel time of the seismic wave in the underground medium is calculated using the above formula, and the corresponding imaging result is inversely obtained.

[0054] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A device for detecting disaster-causing tectonic earthquakes in advance with drilling stopped, characterized in that: It includes a hollow rod body, a shock absorber, a strong spring, a metal impact block, a piston and a hydraulic pressurization system; The hollow rod body is formed into a double-layer structure by an inner tube and an outer tube, and a drill bit is installed at one end of the hollow rod body; the annular channel between the inner tube and the outer tube serves as a first water injection channel; and the first water injection channel is connected to the inner tube near the drill bit; the strong spring, the metal impact block and the piston are all installed in the hollow rod body, and the two ends of the strong spring are respectively connected to one end of the metal impact block and one end of the piston. When the piston is subjected to force, the strong spring will deform and drive the metal impact block to move axially along the inner tube; the shock absorber is installed in the inner tube and away from the drill bit, and is used to place a node-type seismograph The node-type seismograph is used to receive earthquake signals; a second water injection channel is provided on the shock absorber, and the hydraulic pressurization system includes a pressurizing device, one end of the pressurizing device is connected to the water source, and the other end is connected to the inner tube through the first water injection channel or the second water injection channel, and is used to inject high-pressure water into the inner tube. When water is injected through the second water injection channel, it can push the piston to move and cause the strong spring to deform and increase the elastic force, thereby driving the metal impact block to move quickly and hit the drill bit to generate seismic waves. When water is injected through the first water injection channel, the strong spring, metal impact block and piston can be reset.

2. The device for advanced detection of disaster-causing tectonic earthquakes with drilling stopped as claimed in claim 1, characterized in that: The pressurizing device is equipped with two one-way valves, which are respectively connected to the first water injection channel and the second water injection channel, and are used to allow high-pressure water to be unidirectionally injected into the inner tube through any water injection channel as needed.

3. A method for operating the device for detecting tectonic earthquakes in advance with drilling stopped according to claim 1 or 2, characterized in that: The specific steps are: Step 1: Drilling parameter collection: During drilling, a drilling rig is used. A downhole pressure sensor, torque and speed sensor, displacement sensor, and oil pressure sensor are installed on the rig. Each sensor is connected to the drilling rig's data monitoring system to collect speed, torque, displacement, and drilling pressure parameters during the drilling process. The wave velocity of different rock layers is determined by calculating the collected parameters to provide prior data for seismic inversion. Step 2: Determine the initial inversion velocity model: Set a threshold value and divide the wave velocity of the rock layers at different positions in step 1 according to the threshold value. The wave velocity less than the threshold value is a low-velocity area, and the wave velocity greater than or equal to the threshold value is a high-velocity area, thereby obtaining the initial velocity model; Step 3: Collecting seismic reflection waves: Before drilling, a node-type seismometer is installed on each drill rod, and one end of the disaster-causing earthquake advance detection device is equipped with a drill bit and the other end is connected to the drilling rig; when drilling begins, a drill rod is added every time a drill rod is drilled; in the interval between each drill rod addition, a seismic wave is excited using the disaster-causing earthquake advance detection device, and each node-type seismometer receives the seismic data of the excitation. After the excitation and drill rod addition are completed, drilling continues until the entire borehole is drilled, and seismic data corresponding to multiple seismic wave excitations are obtained; Step 4: Data inversion for disaster-causing structure detection: Use the initial velocity model to perform the first inversion on the seismic data collected when the first seismic wave was excited, and obtain the inversion result of the first inversion; then use the inversion result of the first inversion as the initial model for the second inversion, and use the initial model of the second inversion to perform the second inversion on the seismic data collected when the second seismic wave was excited, and obtain the inversion result of the second inversion; and so on, continuously update and iterate until the inversion of all excited seismic waves is completed, and the final result is the inversion result closest to the true one.

4. The working method according to claim 3, characterized in that: In step 1, the wave velocity of different rock layers is determined by collecting parameters and calculating, specifically: Establish the energy index formula: E=T·RPM / A b Among them, E is energy index, T is torque, RPM is speed, A b is the cross-sectional area of ​​the drill bit; The calculation formula of rock wave velocity is established based on energy index: Vp=1500+0.5·E 0.6 Among them, Vp is the rock wave velocity.

5. The working method according to claim 3, characterized in that: The drilling rig is a mining crawler drilling rig.

6. The working method according to claim 3, characterized in that: The length of the drill rod is 2m.

7. The working method according to claim 3, characterized in that: The specific process of exciting seismic waves each time is as follows: the drill bit contacts the bottom of the borehole, the pressure device of the hydraulic pressure system is connected to the hollow rod body, and the hydraulic pressure system injects high-pressure water into the inner tube through the second water injection channel. At this time, the piston is forced to press the strong spring to deform it and increase the elastic force. At the same time, it drives the metal impact block to move toward the drill bit and the speed continues to increase until the metal impact block moves rapidly and hits the drill bit to generate seismic waves. The seismic waves are transmitted to the surrounding coal rock through the drill bit; after completing one excitation, the water in the inner tube is discharged through the second water injection channel, and then water is injected into the first water injection channel. The water enters the inner tube from near the drill bit to push the metal impact block, the strong spring and the piston to reset. After completion, the water in the inner tube is discharged through the first water injection channel, completing the process of exciting seismic waves.

8. The working method according to claim 3, characterized in that: The calculation method of the travel time of the reflected wave of the disaster-causing structure in the inversion process of step 4 is: Where t is the total travel time of the reflected wave; d is the vertical distance from the tunnel face to the disaster-causing structure; L is the reference distance between the receiving point of the node seismometer and the tunnel face; nL and mL are the distances from the seismic wave excitation point and the receiving point of the node seismometer to the tunnel face, respectively; a is the angle between the normal line of the reflection point on the surface of the disaster-causing structure and the parallel line of the tunnel head; Vp is the rock velocity; The travel time of seismic waves in the underground medium is calculated using the above formula, and the corresponding imaging results are obtained by inversion.

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