CN108121010B - Based on the united underground dead face slot wave forward probe method and system in hole lane - Google Patents
Based on the united underground dead face slot wave forward probe method and system in hole lane Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 16
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- 238000001514 detection method Methods 0.000 claims abstract description 38
- 238000003384 imaging method Methods 0.000 claims description 39
- 230000010287 polarization Effects 0.000 claims description 35
- 239000006185 dispersion Substances 0.000 claims description 18
- 230000002159 abnormal effect Effects 0.000 claims description 13
- 230000005284 excitation Effects 0.000 claims description 10
- 238000005516 engineering process Methods 0.000 claims description 9
- 238000001914 filtration Methods 0.000 claims description 8
- 238000001228 spectrum Methods 0.000 claims description 6
- 238000005422 blasting Methods 0.000 claims description 5
- 230000006835 compression Effects 0.000 claims description 4
- 238000007906 compression Methods 0.000 claims description 4
- 239000011159 matrix material Substances 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 238000007781 pre-processing Methods 0.000 claims description 3
- 230000002547 anomalous effect Effects 0.000 abstract 2
- 238000009412 basement excavation Methods 0.000 description 4
- 238000005553 drilling Methods 0.000 description 3
- 230000005641 tunneling Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
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- 239000003245 coal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/40—Seismology; Seismic or acoustic prospecting or detecting specially adapted for well-logging
- G01V1/44—Seismology; Seismic or acoustic prospecting or detecting specially adapted for well-logging using generators and receivers in the same well
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/40—Seismology; Seismic or acoustic prospecting or detecting specially adapted for well-logging
- G01V1/44—Seismology; Seismic or acoustic prospecting or detecting specially adapted for well-logging using generators and receivers in the same well
- G01V1/48—Processing data
- G01V1/50—Analysing data
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Abstract
The present invention relates to a kind of slot wave forward probe method and system, belong to technical field of geophysical exploration, and in particular to one kind is based on the united underground dead face slot wave forward probe method and system in hole lane.The present invention, which utilizes, beats the hole lane combined detection scheme of multi-component and multilevel geophone in deep hole and placement hole in two lateral wall vertical working direction of tunnel, the detection angle of reflection slot wave is effectively expanded, so as to front anomalous body, the especially reflection slot wave image quality of the reflecting surface anomalous body vertical with tunnel improves dead face reflection slot wave forward probe precision.
Description
Technical Field
The invention relates to a trough wave advanced detection method and a trough wave advanced detection system, belongs to the technical field of geophysical exploration, and particularly relates to an underground single-head roadway trough wave advanced detection method and an underground single-head roadway trough wave advanced detection system based on hole-roadway combination.
Background
The advanced detection technology aiming at the geological structure in front of the excavation roadway is a geological guarantee technology which has the advantages of severe detection environment, high technical difficulty, high detection precision requirement and real-time requirement. However, the technology can not only prevent accidents such as gas outburst and water inrush, but also provide geological information for gas drainage, advanced water drainage, optimized tunneling scheme and the like, so that the mining speed is accelerated under the condition of improving safety guarantee.
In the prior art, the real-time advanced detection technology taking blasting excavation as a seismic source does not influence the excavation progress, and can complete the task of real-time advanced detection while tunneling.
However, due to the fact that the space of a tunneling working face is narrow, the line layout in the prior art is limited to linearity, the wave number range of the received wave field space is too narrow, the azimuth accuracy of reflected wave imaging is zero, the imaging quality of the groove wave is poor, and the advanced detection accuracy of the reflected groove wave is affected.
Disclosure of Invention
The invention mainly solves the technical problems of poor channel wave imaging quality and low reflected channel wave advanced detection precision in the prior art, and provides an underground single-headed tunnel channel wave advanced detection method and system based on hole-lane combination.
The technical problem of the invention is mainly solved by the following technical scheme:
a method for advanced detection of groove waves of an underground single-head roadway based on hole-roadway combination comprises the following steps:
a seismic source excitation step, namely, utilizing a seismic source excitation signal at the head of a roadway;
a wave field receiving step, namely receiving wave fields generated by vibration signals by using a plurality of hole mid-detector devices arranged in horizontal holes of two side walls at the head of the roadway and a roadway detector device arranged at two side walls behind the head of the roadway respectively;
a wave field processing step, which is used for processing the received wave field and carrying out offset imaging on the wave field record by adopting a scattering imaging method to obtain a trough wave advanced detection imaging result;
and a geological interpretation step, in which suspicious geological abnormal bodies existing in front of and around the single-headed roadway are interpreted on the offset imaging section, and the position, the scale and the type of the suspicious geological abnormal bodies are determined.
Preferably, the above method for detecting the groove wave advance in the underground single-headed roadway based on the hole-roadway combination includes a signal preprocessing sub-step, where the signal preprocessing sub-step is configured to attenuate random noise in the data record by using polarization filtering, and improve the signal-to-noise ratio of the effective signal, especially the reflected groove wave signal, and specifically includes:
(1) the covariance matrix of the three-component data is calculated within a given time window:
(2) according to the formula | Q- λ I | ═ 0, the characteristic value λ is obtained1、λ2And λ3And corresponding feature vector V1、V2And V3；
(3) Calculating polarization coefficientAnd a polarization filter is constructed by utilizing the polarization coefficient
(4) And respectively acting the polarization filters on the three components to obtain a filtered record, wherein the filtered record filters out a wave field with low polarization degree and reserves a wave field with high polarization degree.
(5) And moving the time window, and repeating the steps until the tail of the record.
Preferably, in the method for advanced detection of the groove wave in the underground single-head roadway based on the hole-roadway combination, the wave field processing step specifically includes a groove wave compression sub-step, specifically, a multi-filtering technology based on S transform is used to calculate the frequency dispersion spectrum of the groove wave data with high precision, a frequency dispersion parameter is picked up on the frequency dispersion spectrum, an inverse frequency dispersion filter is designed by using the frequency dispersion parameter, and then the inverse frequency dispersion filter is applied to the groove wave record to realize compression of the groove wave array.
Preferably, in the above method for advanced detection of slot waves in an underground single-headed tunnel based on hole-tunnel combination, the wave field processing step specifically includes a modulation function determining sub-step, which is configured to calculate a reflected wave travel time t based on a ray tracing technique according to spatial positions and propagation velocity parameters from an excitation point, a reception point to a reflection point, determine a time window with a signal period as a unit according to the reflected wave travel time, and calculate a particle polarization direction based on a mathematical statistical means through amplitude information of the received three-component time windowAnd the direction of the reflected wave rayAccording to the angle, the polarization direction coefficient of the channel wave type used for imaging is calculatedDetermining modulation function for polarization offset imagingWherein α is a given tuning parameter when the wavefield is a LOVE trough wave wavefieldIf it is RayLeigh channel wave, it is
Preferably, the wave field processing substep includes a shift imaging substep, specifically, a modulation function is used for acting on the record to obtain a polarization filtering signal X '(t) ═ X (t) × f (t), and then a scattering imaging method is used to perform shift imaging on the record X' (t) to obtain a final slot wave advance detection imaging result.
The utility model provides an underground single-headed tunnel trough wave advanced detection system based on hole lane is united, includes:
a blasting driving seismic source which is positioned at the head of the roadway and used for exciting a vibration signal;
the in-hole wave detectors are arranged in horizontal holes on two side walls at the head of the roadway, and more than two in-hole wave detectors are arranged in each horizontal hole and used for receiving wave fields generated by vibration signals;
the tunnel detectors are arranged along two side walls behind the head of the tunnel to form two mutually parallel lines and are used for receiving wave fields generated by the vibration signals;
and the signal processing device is used for processing the received wave field, carrying out offset imaging on the wave field record by adopting a scattering imaging method, interpreting suspicious geological abnormal bodies in front of and around the single-headed roadway on an offset imaging section, and determining the position, scale and type of the suspicious geological abnormal bodies.
Preferably, in the above downhole single-head roadway slot wave advanced detection system based on hole-roadway combination, the in-hole detectors are arranged at an interval of 10 meters in a horizontal hole, and more than 6 levels of three-component detectors are arranged in each hole.
Preferably, in the above downhole single-headed roadway slot wave advanced detection system based on hole-roadway combination, the roadway detectors are arranged at intervals of 10 meters, and each measuring line is provided with more than 24 three-component detectors.
Therefore, compared with the prior art, the method effectively expands the detection angle of the reflected channel wave by utilizing the hole-lane combined detection scheme of drilling deep holes on two sides of the lane in the direction vertical to the lane and arranging the multistage detectors in the holes, thereby being capable of improving the advanced detection precision of the reflected channel wave of the single-head lane on the front abnormal body, particularly the reflected channel wave of the abnormal body with the reflecting surface vertical to the lane.
Drawings
FIG. 1 is a schematic view of the observation system of the present invention;
FIG. 2 is a schematic diagram of the signal processing of the roadway detector of the present invention.
Fig. 3 is a schematic diagram of the signal processing of the pore detector of the present invention.
FIG. 4 is a comparison graph of the detection effect of the roadway detectors and the borehole detectors of the present invention on faults perpendicular to the roadway.
Detailed Description
The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.
Example (b):
the observation system for the groove wave advanced detection of the underground coal mine single-headed roadway based on the well-ground combination is designed according to the mode of figure 1.
Firstly, a seismic source point adopts a signal excited by an explosive seismic source in a blasting excavation process as an excitation source, so that the excitation point is usually positioned at the head of a roadway; the receiving points of the roadway are distributed at the rear of the head of the roadway by 5 meters, two measuring lines are respectively arranged on two lateral sides, and each receiving point is distributed with a plurality of three-component receiving points (at least 24 are suggested so as to better identify wave fields) at the interval of 10 meters; respectively drilling horizontal holes with the depth of more than 60 meters at two sides of a position 5 meters away from the head of the roadway, wherein the distance between the detectors in the holes is 10 meters, and each hole is provided with a 6-stage three-component detector;
then, connecting the three-component wave detector with a self-recording type groove wave seismograph by using a data transmission line, and receiving direct waves, refracted waves, reflected waves and other wave fields generated by a vibration signal excited during blasting and digging, and when encountering surrounding abnormal geologic bodies;
the random noise in the data record is attenuated by utilizing polarization filtering, the signal-to-noise ratio of effective signals, particularly reflected channel wave signals, is improved, and the specific algorithm is as follows:
① the covariance matrix of the three-component data is calculated within a given time window:
wherein Q is a covariance matrix formed within the time window: (X)i,Yi,Zi) For the samples of the three components X, Y and Z within the time window,is the average amplitude value of the sampling points in the time window.
② obtaining the characteristic value lambda according to the formula | Q-lambda I | ═ 01、λ2And λ3And corresponding feature vector V1、V2And V3；
③ calculating polarization coefficientsAnd a polarization filter is constructed by utilizing the polarization coefficient
④ applying polarization filters to the three components, respectively, to obtain filtered records which filter out the low polarization wavefields and retain the high polarization wavefields.
⑤ move the time window and repeat the above steps until the end of the record.
Then, a multi-filtering technology based on S transformation is used for calculating a frequency dispersion spectrum of the slot wave data with high precision, frequency dispersion parameters are picked up on the frequency dispersion spectrum, an inverse frequency dispersion filter is designed by using the frequency dispersion parameters, and then the inverse frequency dispersion filter acts on the slot wave record to realize the compression of the slot wave array;
calculating the travel time t of the reflected wave according to the spatial position and the propagation velocity parameters from the excitation point, the receiving point to the reflection point based on the ray tracing technology, determining a time window with the signal period as a unit according to the travel time of the reflected wave, calculating the polarization direction of the particle through the amplitude information of the received three-component time window based on a mathematical statistic means(eigenvector corresponding to maximum eigenvalue) and reflected wave ray directionAccording to the angle theta (as shown in fig. 2 and 3), and calculating the polarization direction coefficient of the channel wave type used for imaging according to the angleDetermining a modulation function for polarization offset imaging as follows:
where α is the given tuning parameter, when the wavefield is a LOVE tank wave wavefieldIf it is RayLeigh channel wave, it is
Using a modulation function to act on the record to obtain a polarization filtering signal X '(t) ═ X (t) × F (t), and then performing offset imaging on the record X' (t) by adopting a scattering imaging method to obtain a final trough wave advanced detection imaging result;
through geological interpretation, suspicious geological anomalies existing in front of and around the single-headed roadway are interpreted on the offset imaging section, and the position, scale and type of the suspicious geological anomalies are determined.
Compared with the prior art, the method effectively expands the detection angle of the reflected channel wave by utilizing the hole-lane combined detection scheme of drilling deep holes on two side walls of the tunnel in the direction vertical to the tunnel and arranging the multistage detectors in the holes, thereby improving the advanced detection precision of the reflected channel wave of the single-head tunnel on the front abnormal body, particularly the reflected channel wave imaging quality and the imaging range (as shown in figure 4) of the abnormal body with the reflecting surface vertical to the tunnel.
Claims (7)
1. A method for advanced detection of groove waves of an underground single-head roadway based on hole-roadway combination is characterized by comprising the following steps:
a seismic source excitation step, namely, utilizing a seismic source excitation signal at the head of a roadway;
a wave field receiving step, namely receiving wave fields generated by vibration signals by using a plurality of hole mid-detector devices arranged in horizontal holes of two side walls at the head of the roadway and a roadway detector device arranged at two side walls behind the head of the roadway respectively;
a wave field processing step, which is used for processing the received wave field and carrying out offset imaging on the wave field record by adopting a scattering imaging method to obtain a trough wave advanced detection imaging result;
a geological interpretation step, in which suspicious geological abnormal bodies existing in front of and around the single-headed roadway are interpreted on the offset imaging section, and the position, scale and type of the suspicious geological abnormal bodies are determined;
wherein,
the wave field processing step specifically comprises a modulation function determining sub-step, which is used for calculating the travel time t of the reflected wave according to the spatial position and the propagation speed parameter from the excitation point, the receiving point to the reflection point based on the ray tracing technology, determining a time window with the signal period as a unit according to the travel time of the reflected wave, and calculating the polarization direction of the particle through the amplitude information of the received three-component time window based on a mathematical statistic meansAnd the direction of the reflected wave rayAccording to the angle, the polarization direction coefficient of the channel wave type used for imaging is calculatedDetermining modulation function for polarization offset imagingWherein α is a given tuning parameter when the wavefield is a LOVE trough wave wavefieldIf it is RayLeigh channel wave, it is
2. The method according to claim 1, wherein the wave field processing step includes a signal preprocessing sub-step for attenuating random noise in the data record by polarization filtering to improve the signal-to-noise ratio of the effective signal, especially the reflected channel wave signal, and specifically includes:
(1) the covariance matrix of the three-component data is calculated within a given time window:
(2) according to the formula | Q- λ I | ═ 0, the characteristic value λ is obtained1、λ2And λ3And corresponding feature vector V1、V2And V3；
(3) Calculating polarization coefficientAnd a polarization filter is constructed by utilizing the polarization coefficient
(4) Respectively acting the polarization filters on the three components to obtain filtered records, wherein the filtered records filter out wave fields with low polarization degrees and reserve wave fields with high polarization degrees;
(5) and moving the time window, and repeating the steps until the tail of the record.
3. The method as claimed in claim 1, wherein the wave field processing step includes a slot wave compression sub-step, specifically, a frequency dispersion spectrum of the slot wave data is calculated with high precision by using a multi-filtering technique based on S transform, frequency dispersion parameters are picked up on the frequency dispersion spectrum, an inverse frequency dispersion filter is designed by using the frequency dispersion parameters, and then the inverse frequency dispersion filter is applied to the slot wave record to compress the slot wave array.
4. The method according to claim 1, wherein the wave field processing substep includes a shift imaging substep, specifically, a modulation function is used for the recording to obtain a polarization filtered signal X '(t) ═ X (t) × f (t), and then a scatter imaging method is used to perform shift imaging on the recording X' (t) to obtain a final slot wave advance detection imaging result.
5. The utility model provides an underground single-headed tunnel trough wave advanced detection system based on hole lane is united which characterized in that includes:
a blasting driving seismic source which is positioned at the head of the roadway and used for exciting a vibration signal;
the in-hole wave detectors are arranged in horizontal holes on two side walls at the head of the roadway, and more than two in-hole wave detectors are arranged in each horizontal hole and used for receiving wave fields generated by vibration signals;
the tunnel detectors are arranged along two side walls behind the head of the tunnel to form two mutually parallel lines and are used for receiving wave fields generated by the vibration signals;
the signal processing device is used for processing the received wave field, carrying out offset imaging on the wave field record by adopting a scattering imaging method, interpreting suspicious geological abnormal bodies in front of and around the single-headed roadway on an offset imaging section, and determining the position, scale and type of the suspicious geological abnormal bodies; calculating the travel time t of the reflected wave according to the spatial positions and propagation speed parameters from the excitation point, the receiving point to the reflection point and based on ray tracing technology, determining a time window with the signal period as a unit according to the travel time of the reflected wave, calculating the polarization direction of the particle through the amplitude information of the received three-component time window and based on mathematical statistics meansAnd the direction of the reflected wave rayThe angle theta, according to which the channel wave class used for imaging is calculatedPolarization direction coefficient of typeDetermining modulation function for polarization offset imagingWherein α is a given tuning parameter when the wavefield is a LOVE trough wave wavefieldIf it is RayLeigh channel wave, it is
6. The system of claim 5, wherein the borehole-roadway based trough wave advanced detection system is characterized in that the borehole-roadway based trough wave advanced detection system is arranged at a distance of 10 meters in a horizontal hole.
7. The system of claim 5, wherein the roadway detectors are arranged at intervals of 10 meters, and more than 24 three-component detectors are arranged in each measuring line.
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| CN108693561B (en) * | 2018-06-14 | 2019-11-08 | 中煤科工集团西安研究院有限公司 | Coal mining seismic acquisition system and method based on wave detector subdivision array |
| CN111399030A (en) * | 2020-02-29 | 2020-07-10 | 山西晋煤集团技术研究院有限责任公司 | Mine roadway slot wave distributed advanced detection system and method |
| CN113075730B (en) * | 2021-03-23 | 2024-05-28 | 西安中地博睿探测科技有限公司 | Automatic extraction method of travel time information in transmission channel wave speed CT imaging |
| CN115980831A (en) * | 2023-01-05 | 2023-04-18 | 山东大学 | Earth-hole combined fine detection method and system |
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| CN104111479A (en) * | 2014-07-17 | 2014-10-22 | 河北煤炭科学研究院 | Underground coal mine in-excavating channel wave seism fore-detection method |
| CN104199110A (en) * | 2014-09-05 | 2014-12-10 | 河北煤炭科学研究院 | Method for channel wave earthquake stereoscopic advanced detection during underground coal mine support |
| CN106610503A (en) * | 2016-11-29 | 2017-05-03 | 北京中矿大地地球探测工程技术有限公司 | Omnidirectional slot wave seismic detection method in coal mine excavation process |
| CN107015273B (en) * | 2017-04-10 | 2018-10-19 | 中煤科工集团西安研究院有限公司 | A kind of coal seam Love type groove wave pressure contracting method and devices based on frequency domain |
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