CN-120491156-B - High-density cross-hole elastic wave CT method and device

CN120491156BCN 120491156 BCN120491156 BCN 120491156BCN-120491156-B

Abstract

The invention discloses a high-density cross-hole elastic wave CT method and a device, which relate to the technical field of intelligent processing of engineering geological image results, and are used for measuring two drilling depths, determining a detection section depth range and detection precision, determining the number and positions of excitation probes and receiving probes required by cross-hole seismic wave CT based on the detection section depth range and the detection precision, and hanging the excitation probes on a plurality of excitation probe mounting positions of a first mooring rope. The invention can provide a high-density cross-hole elastic wave CT method and device, a plurality of excitation probes and receiving probes are designed, any number of probes can be connected with each other to form a string, a plurality of corresponding receiving probes are arranged, the probes can be connected with each other to form a string, a proper number of probes can be selected to cooperate according to the drilling depth or the target detection area position in actual work, high-efficiency data acquisition is realized, and meanwhile, the artificial interference factors are less.

Inventors

WANG MENG
HAN FEI
ZHANG XIAO
CHEN DI
NIU GUANGTIAN
LIU WEI
ZHANG CHAO
CHEN CHEN
ZHANG ZHENGXIN

Assignees

武汉中交工程勘察有限公司

Dates

Publication Date: 20260512
Application Date: 20250718

Claims (6)

1. The high-density cross-hole elastic wave CT method is characterized by comprising the following steps of: Step 1, measuring two drilling depths, determining a detection profile depth range and detection precision, and determining the number and positions of excitation probes (1) and receiving probes (2) required by cross-hole seismic wave CT to be determined based on the detection profile depth range and the detection precision; Step 2, the excitation probes (1) obtained in the step 1 are respectively hung on a plurality of excitation probe mounting positions of the first mooring rope (3), and the receiving probes (2) obtained in the step 2 are respectively hung on a plurality of receiving probe mounting positions of the second mooring rope (4); Step 3, the first mooring rope (3) is wound on a first fixed pulley (5), the first mooring rope (3) for mounting a plurality of excitation probes (1) is put into a first drilling hole (100), the plurality of excitation probes (1) are positioned at the excitation probe positions obtained in the step 1, then the first mooring rope (3) is fixed, the second mooring rope (4) is wound on a second fixed pulley (6), and the second mooring rope (4) for mounting a plurality of receiving probes (2) is put into a second drilling hole (101), so that the plurality of receiving probes (2) are positioned at the receiving probe positions obtained in the step 1, and then the second mooring rope (4) is fixed; Step 4, setting working parameters of a plurality of excitation probes (1) through a computer (102), wherein the working parameters comprise initializing serial numbers of the plurality of excitation probes (1), setting excitation sequence, excitation energy and interruption time; Step 5, starting to collect data, transmitting working parameters of a plurality of excitation probes (1) and a plurality of receiving probes (2) to an acquisition controller (103) by a computer (102), controlling the plurality of excitation probes (1) and the plurality of receiving probes (2) to perform data collection work by the acquisition controller (103) parameters, activating one excitation probe (1) and the corresponding plurality of receiving probes (2) each time to collect data, transmitting the collected data to the computer (102) for storage in turn, and exciting all the excitation probes (1) and the corresponding receiving probes (2) in turn until all ray pair data of a section to be detected are collected; in the step 1, the formula for determining the number of the excitation probes (1) and the receiving probes (2) is as follows: ; Wherein the method comprises the steps of Is the number of excitation probes (1), Is the number of receiving probes (2), Is the depth of the first borehole (100) and the second borehole (101), The detection precision is determined based on the probe spacing; The method for determining the positions of the excitation probe (1) and the receiving probe (2) comprises the steps that the distance between the excitation probe (1) positioned at the bottommost part and the bottom of a first drilling hole (100) is the detection precision, and the excitation probe (1) is arranged upwards at intervals of detection precision based on the sequence of the excitation probes (1); In the step 3, the method for determining the distance between the bottommost excitation probe (1) and the bottom of the first drilling hole (100) comprises the steps of installing a wireless laser ranging sensor (71) at the bottom of the bottommost excitation probe (1), enabling the sensor head of the wireless laser ranging sensor (71) to be vertically downward, and judging the distance between the bottommost excitation probe (1) and the bottom of the first drilling hole (100) by receiving a ranging result emitted by the wireless laser ranging sensor (71) when the first mooring rope (3) is placed into the first drilling hole (100); The high-density cross-hole elastic wave CT device is adopted to realize the high-density cross-hole elastic wave CT method, the device comprises a plurality of excitation probes (1), a plurality of receiving probes (2), a first mooring rope (3), a second mooring rope (4), a first fixed pulley (5), a second fixed pulley (6), a computer (102) and a chip-based acquisition controller (103), the first mooring rope (3) is provided with a plurality of excitation probe mounting positions, the second mooring rope (4) is provided with a plurality of receiving probe mounting positions, the plurality of excitation probes (1) are respectively arranged at the plurality of excitation probe mounting positions, the plurality of receiving probes (2) are respectively arranged at the plurality of receiving probe mounting positions, the first fixed pulley (5) is arranged at one side of an orifice of a first drilling hole (100), the second fixed pulley (6) is arranged at one side of the orifice of a second drilling hole (101), the first mooring rope (3) is wound on the first fixed pulley (5), the plurality of excitation probes (1) are mounted on the first mooring rope (3), the plurality of excitation probes (1) are respectively arranged in the plurality of excitation probes mounting positions, the second mooring rope (1) are respectively arranged in the plurality of receiving probes (4), and the receiving probes (2) are respectively arranged in the second mooring rope (1) at the receiving hole (2), the first mooring rope (1) and the receiving rope (2) is fixed at the second mooring rope (1) and the receiving positions, the first mooring rope (1) and the second mooring rope is positioned on the hole, the plurality of receiving probes (2) are respectively connected with a computer (102) in a communication way, the computer (102) is connected with an acquisition controller (103) in a communication way, and the acquisition controller (103) respectively controls the execution actions of the plurality of excitation probes (1) and the plurality of receiving probes (2).
2. A high density cross-hole elastic wave CT method according to claim 1, further comprising a pair of bottom probe position determining means, one bottom probe position determining means for determining a bottom distance of the bottommost excitation probe (1) of the first tethered rope (3) from the bottom of the first borehole (100) and the other bottom probe position determining means for determining a bottom distance of the bottommost receiving probe (2) of the second tethered rope (4) from the bottom of the second borehole (101).
3. The method of high-density cross-hole elastic wave CT as set forth in claim 2, wherein the bottom probe position determining device comprises a wireless laser ranging sensor (71), a wireless transceiver module (72) and a display (73), wherein the wireless laser ranging sensor (71) is installed on a shell of a bottommost excitation probe (1) or a receiving probe (2), a sensor head of the wireless laser ranging sensor (71) is vertically downward, and the display (73) is installed on the side surfaces of the openings of the first drilling hole (100) and the second drilling hole (101), and the display (73) is in communication connection with the wireless laser ranging sensor (71) through the wireless transceiver module (72).
4. A high-density cross-hole elastic wave CT method as set forth in claim 3, wherein the plurality of excitation probes (1) and the plurality of receiving probes (2) are respectively in communication connection with the computer (102) through communication cables or wireless communication modes.
5. The method of high-density cross-hole elastic wave CT as set forth in claim 4, wherein the acquisition controller (103) comprises a buffer (1031) and a control chip (1032), the buffer (1031) is in communication with the computer (102), and the control chip (1032) is in communication with the buffer (1031) and controls the execution actions of the plurality of excitation probes (1) and the plurality of receiving probes (2) respectively.
6. The method of high-density cross-hole elastic wave CT as set forth in claim 5, wherein said control chip (1032) is communicatively connected to said plurality of excitation probes (1) and said plurality of reception probes (2) by means of communication cables or wireless communication, respectively.

Description

High-density cross-hole elastic wave CT method and device Technical Field The invention relates to the technical field of intelligent processing of engineering geological image achievements, in particular to a high-density cross-hole elastic wave CT method and device. Background The cross-hole seismic wave CT technology utilizes the physical difference characteristic of seismic waves propagating in different media to perform imaging analysis on the underground media. A signal source is activated between two or more boreholes and seismic signals are then received through the subsurface medium in other boreholes. Because the influence of different geologic bodies (such as rock, soil, holes, broken bands and the like) on the propagation speed, amplitude attenuation and the like of the seismic waves is different, the two-dimensional or three-dimensional image of the underground medium between the boreholes can be reconstructed by applying a special inversion algorithm through analyzing the travel time (the time spent by the seismic waves to propagate from the excitation point to the receiving point), the amplitude and other parameters of the received signals, and the condition that the underground geologic structure is presented like the internal structure of a human body is presented by medical CT scanning. The data acquisition process of the cross-hole seismic wave CT method is implemented by utilizing two drilling holes which are not far apart, exciting a signal source at a certain depth in one drilling hole, receiving a signal transmitted by Kong Jianyan soil medium at a certain depth in the other drilling hole, obtaining a pair of ray pairs penetrating through rock-soil bodies among the drilling holes, and combining different depths by moving the depths of an excitation probe and a receiving probe, so that the cross section among the drilling holes is completely covered by the ray pairs. The existing cross-hole elastic wave CT method is mostly in a 'one-shot' mode or a 'one-shot multiple-shot' mode, the heights of the excitation probes or the receiving probes are required to be manually adjusted, more artificial interference can be caused, and the data acquisition efficiency can be influenced. The disadvantage of the prior art is that there is only one excitation source, and the height of the excitation source is manually adjusted for each ray pair acquisition at that depth, which can cause inaccuracy in depth (affecting the quality of subsequent data processing) and greatly reduce the working efficiency. Disclosure of Invention In order to solve the technical problems, the invention provides a high-density cross-hole elastic wave CT method and a device. The following technical scheme is adopted: A high-density cross-hole elastic wave CT method comprises the following steps: step 1, measuring two drilling depths, determining a detection section depth range and detection precision, and determining the number and positions of excitation probes and receiving probes required by cross-hole seismic wave CT based on the detection section depth range and the detection precision; Step 2, respectively hanging the excitation probes obtained in the step 1 on a plurality of excitation probe mounting positions of the first mooring rope, and respectively hanging the receiving probes obtained in the step 2 on a plurality of receiving probe mounting positions of the second mooring rope; Step 3, winding a first mooring rope on a first fixed pulley, putting the first mooring rope carrying a plurality of excitation probes into a first drilling hole, and fixing the first mooring rope after the plurality of excitation probes are positioned at the excitation probe position obtained in the step 1; Step 4, setting working parameters of a plurality of excitation probes through a computer, wherein the working parameters comprise initializing serial numbers of the plurality of excitation probes, setting excitation sequence, excitation energy and interruption time; And 5, starting to collect data, transmitting working parameters of a plurality of excitation probes and a plurality of receiving probes to an acquisition controller by a computer, controlling the plurality of excitation probes and the plurality of receiving probes to perform data acquisition by the parameters of the acquisition controller, activating one excitation probe and the corresponding plurality of receiving probes each time to collect the data, transmitting the collected data to the computer for storage in turn, and exciting all the excitation probes and the corresponding receiving probes until all the ray pair data of the section to be detected are acquired. By adopting the technical scheme, the excitation probes can generate earthquake waves, are connected with each other through the first mooring ropes, are communicated with the acquisition controller and the computer in a communication cable or wireless mode, and the receiving probes can receive the earthquake