CN111879855A - Surrounding rock loosening ring ultrasonic testing acoustic coupling system and application method thereof - Google Patents
Surrounding rock loosening ring ultrasonic testing acoustic coupling system and application method thereof Download PDFInfo
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- CN111879855A CN111879855A CN202010891539.6A CN202010891539A CN111879855A CN 111879855 A CN111879855 A CN 111879855A CN 202010891539 A CN202010891539 A CN 202010891539A CN 111879855 A CN111879855 A CN 111879855A
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- 238000012360 testing method Methods 0.000 title claims abstract description 84
- 239000011435 rock Substances 0.000 title claims abstract description 34
- 230000008878 coupling Effects 0.000 title claims abstract description 32
- 238000010168 coupling process Methods 0.000 title claims abstract description 32
- 238000005859 coupling reaction Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000000523 sample Substances 0.000 claims abstract description 19
- 239000004519 grease Substances 0.000 claims abstract description 17
- 235000014121 butter Nutrition 0.000 claims description 9
- 238000005553 drilling Methods 0.000 claims description 3
- 235000013267 Pinus ponderosa Nutrition 0.000 claims description 2
- 241000555277 Pinus ponderosa Species 0.000 claims description 2
- 229910052755 nonmetal Inorganic materials 0.000 claims description 2
- 239000000463 material Substances 0.000 claims 1
- 206010057175 Mass conditions Diseases 0.000 abstract description 2
- 238000005259 measurement Methods 0.000 abstract 2
- 238000013461 design Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005266 casting Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/07—Analysing solids by measuring propagation velocity or propagation time of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/223—Supports, positioning or alignment in fixed situation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/28—Details, e.g. general constructional or apparatus details providing acoustic coupling, e.g. water
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/011—Velocity or travel time
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0232—Glass, ceramics, concrete or stone
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Acoustics & Sound (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention relates to an acoustic coupling system for ultrasonic testing of a loose circle of surrounding rock and an application method thereof. During testing, sound waves emitted by the sound wave testing probe firstly enter water in the supporting tube, then enter the tube wall of the supporting tube, then enter grease filled between the supporting tube and the sound testing hole, and finally enter surrounding rock of the hole wall. According to the invention, grease is used as an acoustic coupling medium to fill the supporting tube and the acoustic measurement hole gap, so that the acoustic coupling device can well adapt to the broken rock mass condition, and a good acoustic coupling environment between the measurement supporting tube and the hole wall is ensured; and the supporting tube can provide a supporting function and prevent the hole wall of the sounding hole from collapsing.
Description
The technical field is as follows:
the invention relates to an acoustic coupling system for ultrasonic testing of a surrounding rock loosening ring and an application method thereof.
Background art:
the size of the loose ring of the tunnel surrounding rock is an important basis for designing anchor bolt support parameters. Common surrounding rock loosening ring testing methods comprise a geological radar detection method, a multi-point displacement measurement method, a sound wave method and the like. Compared with other methods, the acoustic wave method has the advantages of high precision, low cost and simple and convenient operation, so that the acoustic wave method is more widely applied.
The premise of obtaining ideal results in the sonic testing is that the inside of the testing hole has a good acoustic coupling environment. In the traditional method, the coupling between the acoustic wave test probe and the hole wall is realized by injecting water or filling a water band into the test hole. However, in high stress soft rock tunnels, there is a higher risk of collapse of the manholes. In order to research the evolution law of the tunnel surrounding rock loosening ring along with the advance of the tunnel face or the extension of time, a plurality of tests are needed for a long time, but the traditional method is easy to collapse in the process, so that the test cannot be carried out. The accuracy of the acoustic wave test can be greatly influenced by the collapse and deformation of the hole wall, and the acoustic wave method test is difficult to develop in the high-stress soft rock tunnel.
The invention content is as follows:
the invention aims to solve the problems in the prior art, namely the invention aims to provide an acoustic coupling system for ultrasonic testing of a surrounding rock loosening ring and an application method thereof, the design is reasonable, the stability of an acoustic testing hole can be maintained, and the good coupling between a probe and the surrounding rock can be ensured.
In order to achieve the purpose, the invention adopts the technical scheme that: the utility model provides a country rock pine circle ultrasonic testing acoustic coupling system, is including laying at least one sound survey hole at the test position, the downthehole stay tube that is equipped with of sound survey, the interior end of stay tube is sealed, outer end is uncovered, and it has the butter to fill between stay tube and the sound survey hole, and the stay tube is inside to have installed water, and the inside aquatic of stay tube is provided with sound wave test probe.
Furthermore, the sound measuring hole is in an inclined shape with a low inner end and a high outer end.
Furthermore, the supporting tube is a hollow round tube made of a non-metal material.
Furthermore, the supporting pipe is a hard PVC pipe.
Furthermore, the sound wave test probe is connected with a test instrument positioned outside the supporting tube through a test lead.
The other technical scheme adopted by the invention is as follows: an application method of an acoustic coupling system for ultrasonic testing of a surrounding rock loosening ring comprises the following steps:
(1) arranging at least one acoustic testing hole with the depth meeting the testing requirement at the position to be tested, wherein the acoustic testing hole is in an inclined shape with a low inner end and a high outer end, and then injecting a proper amount of butter into the acoustic testing hole;
(2) inserting a supporting tube into the acoustic hole, wherein the supporting tube extrudes grease to cause that the gap between the supporting tube and surrounding rock of the hole wall is filled with grease due to the fact that a certain amount of grease is contained in the acoustic hole; adding water into the supporting tube, wherein the water, the supporting tube and the butter form an acoustic coupling system;
(3) debugging an acoustic wave test instrument, and connecting an acoustic wave test probe; the sound wave test probe extends into the water in the supporting pipe to acquire a sound wave speed value;
(4) and (5) continuously repeating the step (3) along with the advancing of the tunnel face or the prolonging of the time, so as to measure the evolution law of the tunnel surrounding rock loosening ring.
Further, in the step (1), a drilling machine is adopted to open the sound testing hole at the position to be tested.
Further, in the step (1), grease is injected into the acoustic testing hole through a pneumatic high-pressure oiling machine.
Compared with the prior art, the invention has the following effects: (1) the acoustic coupling device is reasonable in design, grease is used as an acoustic coupling medium to fill the supporting tube and the acoustic measuring hole gap, so that the acoustic coupling device can be well adapted to the broken rock mass condition, leakage cannot occur, and a good acoustic coupling environment between the measuring supporting tube and the hole wall is ensured; (2) the supporting tube can provide a supporting function in the sounding hole to prevent the hole wall of the sounding hole from collapsing; (3) the water in the supporting tube can ensure a good acoustic coupling environment between the acoustic wave test probe and the supporting tube.
Description of the drawings:
FIG. 1 is a schematic construction of an embodiment of the present invention;
fig. 2 is a schematic diagram of a butter injection process in an embodiment of the invention.
In the figure:
1-hole wall surrounding rock; 2-sounding the hole; 3-butter oil; 4-a hose; 5-a pneumatic high-pressure oiling machine; 6-supporting the tube; 7-testing the probe; 8-sonic testing instrument; 9-test wires; 10-water.
The specific implementation mode is as follows:
the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, are merely for convenience of description of the present invention, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
As shown in fig. 1-2, the acoustic coupling system for ultrasonic testing of the loose circle of surrounding rock is used for solving the problem that the development of the acoustic testing is difficult due to the high risk of collapse of the testing holes in the high-stress soft rock tunnel, and comprises at least one acoustic testing hole 2 arranged at a testing position, wherein a supporting tube 6 is inserted into the acoustic testing hole 2, the inner end of the supporting tube 6 is closed, the outer end of the supporting tube 6 is open, grease 3 is filled between the supporting tube 6 and the acoustic testing hole 2, water 10 is arranged inside the supporting tube 6, an acoustic testing probe 7 is arranged in the water inside the supporting tube 6, and the acoustic testing probe 7 is connected with a testing instrument 8 located outside the supporting tube 3 through a testing wire 6. During testing, sound waves emitted by the sound wave testing probe 7 firstly enter water in the supporting pipe 6, then enter the pipe wall of the supporting pipe 6, then enter grease 3 filled between the supporting pipe 6 and the sound testing hole 2, and then enter the hole wall surrounding rock 1.
In this embodiment, in order to prevent the grease 3 in the sounding hole 2 and the water 10 in the support tube 6 from flowing out, the sounding hole 2 is inclined such that the inner end is low and the outer end is high.
In this embodiment, the support tube 6 is a hollow round tube made of a non-metallic material, and preferably a rigid PVC tube. The outer diameter of the supporting tube 6 is slightly smaller than the diameter of the sound measuring hole 2, and the inner diameter of the supporting tube 6 is larger than the outer diameter of the sound wave testing probe 7.
It should be noted that the inner end of the support tube 6 is the end extending into the sounding hole 2, and the outer end of the support tube 6 is the end extending out of the sounding hole 2. The inner and outer ends of the sounding hole have the same position as the inner and outer ends of the supporting tube.
In this embodiment, the application method of the surrounding rock loosening coil ultrasonic testing acoustic coupling system includes the following steps:
(1) arranging at least one acoustic hole 2 with the depth meeting the test requirement at a position to be tested by adopting a drilling machine, wherein the acoustic hole 2 is in an inclined shape with a low inner end and a high outer end, and then injecting a proper amount of butter 3 into the acoustic hole 2 through a pneumatic high-pressure oiling machine 5;
(2) inserting a supporting tube 6 into the sounding hole 2, wherein a certain amount of grease 3 is contained in the sounding hole 2, and grease can be filled in gaps between the supporting tube 6 and the wall surrounding rock 1 of the sounding hole 2 due to the fact that the supporting tube 6 extrudes the grease 3; adding water 10 into the support tube 6, wherein the water 10, the support tube 6 and the butter 3 jointly form an acoustic coupling system;
(3) debugging an acoustic wave test instrument 8, and connecting an acoustic wave test probe 7; the sound wave test probe extends into the water in the supporting pipe to acquire a sound wave speed value;
(4) and (5) continuously repeating the step (3) along with the advancing of the tunnel face or the prolonging of the time, so as to measure the evolution law of the tunnel surrounding rock loosening ring.
If the invention discloses or relates to parts or structures which are fixedly connected to each other, the fixedly connected parts can be understood as follows, unless otherwise stated: a detachable fixed connection (for example using bolts or screws) is also understood as: non-detachable fixed connections (e.g. riveting, welding), but of course, fixed connections to each other may also be replaced by one-piece structures (e.g. manufactured integrally using a casting process) (unless it is obviously impossible to use an integral forming process).
In addition, terms used in any technical solutions disclosed in the present invention to indicate positional relationships or shapes include approximate, similar or approximate states or shapes unless otherwise stated.
Any part provided by the invention can be assembled by a plurality of independent components or can be manufactured by an integral forming process.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.
Claims (8)
1. The utility model provides a surrounding rock pine circle ultrasonic testing acoustic coupling system and application method thereof, includes at least one sound survey hole of laying in the test position, its characterized in that: the acoustic testing device is characterized in that a supporting tube is inserted into the acoustic testing hole, the inner end of the supporting tube is closed, the outer end of the supporting tube is open, butter is filled between the supporting tube and the acoustic testing hole, water is filled in the supporting tube, and an acoustic testing probe is arranged in the water in the supporting tube.
2. The surrounding rock loosening coil ultrasonic testing acoustic coupling system of claim 1, wherein: the sound measuring hole is in an inclined shape with a low inner end and a high outer end.
3. The surrounding rock loosening coil ultrasonic testing acoustic coupling system of claim 1, wherein: the supporting tube is a hollow round tube made of nonmetal materials.
4. The surrounding rock loosening coil ultrasonic testing acoustic coupling system of claim 3, wherein: the supporting pipe is a hard PVC pipe.
5. The surrounding rock loosening coil ultrasonic testing acoustic coupling system of claim 1, wherein: the sound wave test probe is connected with a test instrument positioned outside the supporting tube through a test lead.
6. An application method of an acoustic coupling system for ultrasonic testing of a surrounding rock loosening ring is characterized by comprising the following steps: the surrounding rock loosening ring ultrasonic testing acoustic coupling system comprises the following steps:
(1) arranging at least one acoustic testing hole with the depth meeting the testing requirement at the position to be tested, wherein the acoustic testing hole is in an inclined shape with a low inner end and a high outer end, and then injecting a proper amount of butter into the acoustic testing hole;
(2) inserting a supporting tube into the acoustic hole, wherein the supporting tube extrudes grease to cause that the gap between the supporting tube and surrounding rock of the hole wall is filled with grease due to the fact that a certain amount of grease is contained in the acoustic hole; adding water into the supporting tube, wherein the water, the supporting tube and the butter form an acoustic coupling system;
(3) debugging an acoustic wave test instrument, and connecting an acoustic wave test probe; the sound wave test probe extends into the water in the supporting pipe to acquire a sound wave speed value;
(4) and (5) continuously repeating the step (3) along with the advancing of the tunnel face or the prolonging of the time, so as to measure the evolution law of the tunnel surrounding rock loosening ring.
7. The application method of the surrounding rock loosening coil ultrasonic testing acoustic coupling system according to claim 6, characterized in that: in the step (1), a drilling machine is adopted to open a sound testing hole at the position to be tested.
8. The application method of the surrounding rock loosening coil ultrasonic testing acoustic coupling system according to claim 6, characterized in that: in the step (1), grease is injected into the acoustic testing hole through a pneumatic high-pressure oiling machine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010891539.6A CN111879855B (en) | 2020-08-31 | 2020-08-31 | Surrounding rock loose coil ultrasonic test acoustic coupling system and application method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010891539.6A CN111879855B (en) | 2020-08-31 | 2020-08-31 | Surrounding rock loose coil ultrasonic test acoustic coupling system and application method thereof |
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| CN111879855A true CN111879855A (en) | 2020-11-03 |
| CN111879855B CN111879855B (en) | 2024-06-14 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112345647A (en) * | 2021-01-05 | 2021-02-09 | 中南大学 | Surrounding rock loosening ring test method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104792965A (en) * | 2015-02-01 | 2015-07-22 | 山东科技大学 | Drilling energy-based surrounding rock loosing circle test method |
| CN105467014A (en) * | 2015-12-31 | 2016-04-06 | 中国科学院武汉岩土力学研究所 | Device and method for automatically testing loose circle of surrounding rock in dry hole |
| CN108802193A (en) * | 2018-03-30 | 2018-11-13 | 中国平煤神马能源化工集团有限责任公司 | A kind of detecting devices and detection method of Exploring Loose Rock Country in Tunnels |
| CN109184747A (en) * | 2018-10-24 | 2019-01-11 | 中南大学 | A kind of method for protecting support of Deep Soft Rock Tunnel |
| CN212646583U (en) * | 2020-08-31 | 2021-03-02 | 福州大学 | Surrounding rock loosening ring ultrasonic testing acoustic coupling system |
-
2020
- 2020-08-31 CN CN202010891539.6A patent/CN111879855B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104792965A (en) * | 2015-02-01 | 2015-07-22 | 山东科技大学 | Drilling energy-based surrounding rock loosing circle test method |
| CN105467014A (en) * | 2015-12-31 | 2016-04-06 | 中国科学院武汉岩土力学研究所 | Device and method for automatically testing loose circle of surrounding rock in dry hole |
| CN108802193A (en) * | 2018-03-30 | 2018-11-13 | 中国平煤神马能源化工集团有限责任公司 | A kind of detecting devices and detection method of Exploring Loose Rock Country in Tunnels |
| CN109184747A (en) * | 2018-10-24 | 2019-01-11 | 中南大学 | A kind of method for protecting support of Deep Soft Rock Tunnel |
| CN212646583U (en) * | 2020-08-31 | 2021-03-02 | 福州大学 | Surrounding rock loosening ring ultrasonic testing acoustic coupling system |
Non-Patent Citations (2)
| Title |
|---|
| 吴涛;戴俊;杜美利;武宇;高玉柱;杨凡;邹清祺;: "基于声波法测试技术的巷道围岩松动圈测定", 煤矿安全, no. 01, 20 January 2015 (2015-01-20) * |
| 戴俊;杨凡;武宇;邹清祺;: "RSMSY5(N)声波仪在巷道围岩松动圈测试中的应用", 煤炭技术, no. 12, 10 December 2014 (2014-12-10) * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112345647A (en) * | 2021-01-05 | 2021-02-09 | 中南大学 | Surrounding rock loosening ring test method |
| CN112345647B (en) * | 2021-01-05 | 2021-04-23 | 中南大学 | Surrounding rock loosening ring test method |
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| CN111879855B (en) | 2024-06-14 |
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