CN202886202U - Ultrasonic and acoustic emission test system for true triaxial test - Google Patents
Ultrasonic and acoustic emission test system for true triaxial test Download PDFInfo
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- CN202886202U CN202886202U CN 201220571961 CN201220571961U CN202886202U CN 202886202 U CN202886202 U CN 202886202U CN 201220571961 CN201220571961 CN 201220571961 CN 201220571961 U CN201220571961 U CN 201220571961U CN 202886202 U CN202886202 U CN 202886202U
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Abstract
The utility model discloses an ultrasonic and acoustic emission test system for a true triaxial test. A true triaxial test device is provided with pressurizing units on six sides, ultrasonic and acoustic emission coupling test transducers are arranged between corresponding faces of the pressurizing units of all sides and a rock block, a communication terminal of at least one ultrasonic and acoustic emission coupling test transducer is connected with a signal output terminal of a multichannel ultrasonic flaw detector, communication terminals of the other ultrasonic and acoustic emission coupling test transducers are respectively connected to a signal input terminal of the multichannel ultrasonic flaw detector and a signal receiving terminal of an acoustic emission instrument through a signal shunt, and both the acoustic emission instrument and the multichannel ultrasonic flaw detector are both connected to a computer. According to the ultrasonic and acoustic emission test system for the true triaxial test, the ultrasonic and acoustic emission test on the same rock block can be carried out, more comprehensive data information can be provided for the understanding of the deformation, law breaking and mechanical mechanism of rocks, and the adverse effect on test results caused by the differences of different rocks is avoided.
Description
Technical field
The utility model relates to rock failure mechanism of rock experimental technique field, is specifically related to a kind of true triaxial test ultrasound wave and Acoustic Emission Testing System.
Technical background
Acoustic emission is the instantaneous elasticity ripple that is produced by rapid release of energy in stress raisers source in the material, acoustic emission is a kind of common physical phenomenon, the frequency range of various material acoustic emission signals is very wide, the superaudio from the audio frequency of the infra-acoustic frequency of several Hz, 20Hz～20K Hz to several MHz; The variation range of acoustic emission signal amplitude is also very large, the seismic event from the microcosmic dislocation motion of 10m to the 1m magnitude.If the strain energy that acoustic emission discharges is enough large, just can produce the audible sound of people's ear.Have acoustic emission to occur when most of material deformations and fracture, but the acoustic emission signal intensity of many materials is very weak, people's ear can not directly be heard, need to just can detect by the electronic device of sensitivity.Earlier 1970s, it is on-the-spot that the research of acoustic emission has been moved towards gradually from the laboratory.The early 1980s, U.S. PAC company introduces acoustic emission detection system with little process computer technology of modern times, designed less location, the second generation source acoustic emission detection instrument of volume and weight, and developed a series of multi-function high grades and detected and data analysis software.Enter the nineties, the third generation digital multi-channel acoustic emission detection analytic system that the computerize degree is higher, volume and weight is less that Development and Production has successively been distinguished by the roc Xiang Science and Technology Ltd. of U.S. PAC company, U.S. DW company, German Vallen Systeme company and China, these system's decapacitation are carried out acoustic emission parameters and are measured in real time outside the harmony emissive source location, also can directly carry out observation, demonstration, record and the spectrum analysis of acoustic emission waveform.People have been widely used in acoustic emission petrochemical industry, power industry, material test, civil engineering, space flight and aviation industry, metal processing, transportation and some other industry at present.
Ultrasound wave is the sound wave that frequency is higher than 20KHz, because ultrasonic frequency is very high, wavelength is very short, thereby does not have diffraction phenomena to disturb in communication process, so the rectilinear propagation that ripple is propagated when test is better, directivity is stronger, has increased feasibility and the accuracy of test.The second, because different media are different to hyperacoustic receptivity, gas is very strong to hyperacoustic receptivity, and ultrasound wave almost can not be propagated in gas, and the receptivity of solid is then very weak.Utilize the difference of ultrasound wave travel-time and speed in the rock sample of micro-crack is arranged according to this principle, study expansion and the volume change situation of various rock samples crackle in compression process.Ultrasound wave is used for the diagnosis of medical science aspect at first, afterwards through developing into a kind of important means of underground works detection, geological hazards prediction, engineering Non-Destructive Testing etc.The nonmetal ultrasonic defectoscope is widely used in the detection of the aspects such as concrete and rock-soil material intensity, thickness, homogeneity, damage, but the control system of ultrasonic investigation mostly is manual control, also namely reach manually opened transmitting and receiving behind a certain state, this is difficult to meet the demands for adding the higher test of rate of debarkation in the process of the test, and mostly is one one receipts or two a receipts.The maturation of computer technology and the development of robotization be so that the development of multiple path ultrasonic flaw detector has been tending towards ripe, and use in a plurality of fields, and this just provides strong technical support for the utility model.
Ultrasound wave or acoustic emission test technology are applied in the relevant test of rock material both at home and abroad, and have done a large amount of analytical works.But up to the present, most is to use separately, even if the associating use also only is separately to adopt separately two systems to test, namely a sillar carries out ultrasonic investigation, another sillar carries out acoustic emission test, do not accomplish real coupling measurement, and only be used for conventional uniaxial test, and in three axles and true triaxial test, it is not yet seen relevant report.In addition, acoustic emission detection is mainly used in rock material, defective changes with exogenousd variables such as load, times in process of the test time reality or continuous information, simultaneously, it can only provide position, activity and the intensity of acoustic emission source at present, can not provide character and the size of defective in the acoustic emission source, still need depend on other lossless detection method and review.
The utility model content
The purpose of this utility model is for above-mentioned technical matters, a kind of true triaxial test ultrasound wave and Acoustic Emission Testing System are provided, this system can carry out ultrasound wave and acoustic emission test to same sillar, can provide more comprehensively data message for distortion, Regularity and the mechanical mechanism of understanding rock, avoid the difference of different sillars self to the test result adverse effect.
For realizing this purpose, true triaxial test ultrasound wave and Acoustic Emission Testing System that the utility model is designed, comprise actual triaxial testing apparatus, computer and Acoustic radiating instrument, it is characterized in that: it also comprises ultrasound wave and acoustic emission coupling measurement transducer, multiple path ultrasonic flaw detector and signal shunt, wherein, described actual triaxial testing apparatus has six presser unit, ultrasound wave and acoustic emission coupling measurement transducer are set between the corresponding surface of every one side presser unit and sillar, the signal output part of the communication ends connecting multi-channel ultra-sonic defect detector of at least one ultrasound wave and acoustic emission coupling measurement transducer, the communication ends of remaining ultrasound wave and acoustic emission coupling measurement transducer is by signal the shunt respectively signal input part of connecting multi-channel ultra-sonic defect detector and the signal receiving end of Acoustic radiating instrument, and described Acoustic radiating instrument is connected with multiple path ultrasonic flaw detector and is connected computer.
Be equipped with the loading steel plate between the corresponding surface of described every one side presser unit and sillar, offer the transducer mounting hole on the described loading steel plate, described ultrasound wave and acoustic emission coupling measurement transducer are arranged in the transducer mounting hole, described ultrasound wave is connected spring and is connected with the bottom of transducer mounting hole with acoustic emission coupling measurement transducer, described ultrasound wave and acoustic emission coupling measurement transducer are arranged vertically with the loading steel plate.
Adopt butter or vaseline coupling between described ultrasound wave and acoustic emission coupling measurement transducer and the sillar.
The bottom of described transducer mounting hole is fixed with rigid gasket, the bottom of ultrasound wave and acoustic emission coupling measurement transducer is fixed with flexible gasket, described spring is arranged between rigid gasket and the flexible gasket, also is provided with the transducer routing hole that is communicated with the transducer mounting hole on the described loading steel plate.
In the technique scheme, it also comprises signal amplifier, and described signal shunt is by the signal receiving end of signal amplifier connecting acoustic emission instrument.
Described a plurality of ultrasound wave becomes space distribution with acoustic emission coupling measurement transducer.
The utility model adopts the scheme of arranging the transducer putting hole loading steel plate; guaranteed that ultrasound wave contacts with sillar in process of the test all the time with acoustic emission coupling measurement transducer; prevent simultaneously the violent infringement that destroys transducer of sillar, play the effect of protection transducer.The design of this transducer charger can ensure again the transducer normal operation when not affecting the test specimen uniform stressed.When the layout of transducer, transducer arrangement can not be positioned at same plane at sample different surfaces and its line, to guarantee the space orientation of acoustic emission.Adopt ultrasound wave and acoustic emission coupling measurement transducer, improved the utilization factor of transducer.Signal wire adopts double-deck line, avoids the interference of outside electromagnetic signal, especially alternating current.The signal wire that links to each other with transducer is derived from the wire hole of transducer charger, and links to each other with the multi channel signals shunt, has guaranteed normal transmission and the reception of ultrasound wave and acoustic emission signal.The utility model has solved in the true triaxial test transducer safely placement and reasonable Arrangement and the problems such as acoustic emission and ultrasonic wave-coupled test, same sillar is tested, can provide more comprehensively data message for distortion, Regularity and the mechanical mechanism of understanding rock, avoid the difference of different sillars self to the test result adverse effect.
The utility model is by arranging acoustic emission coupling measurement transducer, multiple path ultrasonic flaw detector and Acoustic radiating instrument, so that native system utilizes said method can obtain the closure in sillar crack in the process of the test, cracking, the bump number of the acoustic emission that friction shows after connecting and connecting, the position, frequency, amplitude, energy etc. are velocity of wave between feature and a plurality of measuring points of sillar over time, wave amplitude, wavelength etc. are feature over time, in conjunction with ess-strain curve over time, can accurately identify rock crackle forming and play resistance to spalling, the rule of instable growth of crack intensity and rock Damage-fracture Evolution.For distortion, Regularity and the mechanical mechanism of being familiar with sillar provides more comprehensively data message.
In addition, technical solutions of the utility model are succinct, and means of testing is reliable, can from the more information of same test monitoring, obtain more fully understanding to rock burst mechanism.Measuring point to the different size rock is optimized, this equipment and system all can use in indoor and outdoors true triaxial test, can be widely used in the research of the Engineering Rock Mechanics problems such as Hydraulic and Hydro-Power Engineering, traffic engineering, Mineral Engineering, energy underground storage, also can be used for the correlative studys such as earthquake mechanism and prediction.
Description of drawings
Fig. 1 is one-piece construction block diagram of the present utility model;
Fig. 2 is the structural representation of presser unit in the utility model, loading steel plate and sillar part;
Wherein, 1-actual triaxial testing apparatus, 1.1-presser unit, 2-computer, 3-Acoustic radiating instrument, 4-loading steel plate, 5-ultrasound wave and acoustic emission coupling measurement transducer, 6-multiple path ultrasonic flaw detector, 7-signal shunt, 8-sillar, 9-transducer mounting hole, 10-spring, 11-rigid gasket, 12-flexible gasket, 13-signal amplifier, 14-transducer routing hole.
Embodiment
The utility model is described in further detail below in conjunction with drawings and Examples:
As illustrated in fig. 1 and 2 true triaxial test ultrasound wave and Acoustic Emission Testing System, comprise actual triaxial testing apparatus 1, computer 2, Acoustic radiating instrument 3, ultrasound wave and acoustic emission coupling measurement transducer 5, multiple path ultrasonic flaw detector 6 and signal shunt 7, wherein, described actual triaxial testing apparatus 1 has six presser unit 1.1, ultrasound wave and acoustic emission coupling measurement transducer 5 are set between the corresponding surface of every one side presser unit 1.1 and sillar 8, the signal output part of the communication ends connecting multi-channel ultra-sonic defect detector 6 of at least one ultrasound wave and acoustic emission coupling measurement transducer 5, the communication ends of remaining ultrasound wave and acoustic emission coupling measurement transducer 5 is by signal the shunt 7 respectively signal input part of connecting multi-channel ultra-sonic defect detectors 6 and the signal receiving end of Acoustic radiating instrument 3, and Acoustic radiating instrument 3 is connected with multiple path ultrasonic flaw detector and is all connected computer 2.Above-mentioned ultrasound wave and acoustic emission coupling measurement transducer 5 are bought for market, and its sensor technology parameter is chosen as: bandwidth 100 ~ 500kHz, and resonance frequency 400kHz, sensitivity is greater than 65dB.
In the technique scheme, be equipped with between the corresponding surface of every one side presser unit 1.1 and sillar 8 and load steel plate 4, load on the steel plate 4 and offer transducer mounting hole 9, be provided with ultrasound wave and acoustic emission coupling measurement transducer 5 in the transducer mounting hole 9, ultrasound wave is connected with acoustic emission coupling measurement transducer and is connected with the bottom of transducer mounting hole 9 by spring 10, and ultrasound wave and acoustic emission coupling measurement transducer 5 and loading steel plate 4 are arranged vertically.Consider that ultrasound wave and acoustic emission coupling measurement transducer 5 can only bear limited pressure, can not directly under the pressing machine load, work, when the transducer charger designs, adopt the scheme of arranging that loading steel plate 4 transducer mounting hole 9 is placed transducer.
In the technique scheme, adopt butter or vaseline coupling between ultrasound wave and acoustic emission coupling measurement transducer 5 and the sillar 8.Described butter or vaseline are as the couplant between transducer and the rock.
In the technique scheme, the bottom of transducer mounting hole 9 is fixed with rigid gasket 11, the bottom of ultrasound wave and acoustic emission coupling measurement transducer 5 is fixed with flexible gasket 12, between rigid gasket 11 and the flexible gasket 12 spring 10 is set, loads on the steel plate 4 and also be provided with the transducer routing hole 14 that is communicated with transducer mounting hole 9.Above-mentioned transducer mounting hole 9 is arranged vertically with loading steel plate 4, transducer routing hole 14 is arranged vertically with transducer mounting hole 9, the circuit line of ultrasound wave and acoustic emission coupling measurement transducer 5 is walked out from transducer routing hole 14, spring 10 is separately to ultrasound wave and acoustic emission coupling measurement transducer 5 applied thrusts, one end of spring 10 links to each other with rigid gasket 11 and is placed on transducer mounting hole 9 bottoms, and the other end of spring 10 applies less thrust by 12 pairs of ultrasound waves of flexible gasket and acoustic emission coupling measurement transducer 5.
In the technique scheme, it also comprises signal amplifier 13, and signal shunt 7 is by the signal receiving end of signal amplifier 13 connecting acoustic emission instrument 3.
In the technique scheme, 5 one-tenth space distributions of described a plurality of ultrasound waves and acoustic emission coupling measurement transducer.Ultrasound wave and acoustic emission coupling measurement transducer 5, the not ipsilateral and its line that are arranged in sillar can not be positioned at same plane, acoustic emission end and receiving end link to rare two through main fracture faces.
In the technique scheme, the angle between each ultrasound wave and the acoustic emission coupling measurement transducer 5 is preferably in more than the 30o.
The content that this instructions is not described in detail belongs to the known prior art of this area professional and technical personnel.
Claims (6)
1. a true triaxial test ultrasound wave and Acoustic Emission Testing System, comprise actual triaxial testing apparatus (1), computer (2) and Acoustic radiating instrument (3), it is characterized in that: it also comprises ultrasound wave and acoustic emission coupling measurement transducer (5), multiple path ultrasonic flaw detector (6) and signal shunt (7), wherein, described actual triaxial testing apparatus (1) has six presser unit (1.1), ultrasound wave and acoustic emission coupling measurement transducer (5) are set between the corresponding surface of every one side presser unit (1.1) and sillar (8), the signal output part of the communication ends connecting multi-channel ultra-sonic defect detector (6) of at least one ultrasound wave and acoustic emission coupling measurement transducer (5), the communication ends of remaining ultrasound wave and acoustic emission coupling measurement transducer (5) is by signal shunt (7) the respectively signal input part of connecting multi-channel ultra-sonic defect detector (6) and the signal receiving end of Acoustic radiating instrument (3), and described Acoustic radiating instrument (3) is connected 6 with multiple path ultrasonic flaw detector) all connect computer (2).
2. true triaxial test ultrasound wave according to claim 1 and Acoustic Emission Testing System, it is characterized in that: be equipped with between the corresponding surface of described every one side presser unit (1.1) and sillar (8) and load steel plate (4), offer transducer mounting hole (9) on the described loading steel plate (4), described ultrasound wave and acoustic emission coupling measurement transducer (5) are arranged in the transducer mounting hole (9), described ultrasound wave is connected 5 with acoustic emission coupling measurement transducer) be connected with the bottom of transducer mounting hole (9) by spring (10), described ultrasound wave and acoustic emission coupling measurement transducer (5) are arranged vertically with loading steel plate (4).
3. true triaxial test ultrasound wave according to claim 2 and Acoustic Emission Testing System is characterized in that: adopt butter or vaseline coupling between described ultrasound wave and acoustic emission coupling measurement transducer (5) and the sillar (8).
4. true triaxial test ultrasound wave according to claim 2 and Acoustic Emission Testing System, it is characterized in that: the bottom of described transducer mounting hole (9) is fixed with rigid gasket (11), the bottom of ultrasound wave and acoustic emission coupling measurement transducer (5) is fixed with flexible gasket (12), described spring (10) is arranged between rigid gasket (11) and the flexible gasket (12), also is provided with the transducer routing hole (14) that is communicated with transducer mounting hole (9) on the described loading steel plate (4).
5. true triaxial test ultrasound wave according to claim 1 and Acoustic Emission Testing System, it is characterized in that: it also comprises signal amplifier (13), and described signal shunt (7) is by the signal receiving end of signal amplifier (13) connecting acoustic emission instrument (3).
6. true triaxial test ultrasound wave according to claim 1 and Acoustic Emission Testing System, it is characterized in that: described a plurality of ultrasound waves become space distribution with acoustic emission coupling measurement transducer (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220571961 CN202886202U (en) | 2012-10-31 | 2012-10-31 | Ultrasonic and acoustic emission test system for true triaxial test |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201220571961 CN202886202U (en) | 2012-10-31 | 2012-10-31 | Ultrasonic and acoustic emission test system for true triaxial test |
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| CN202886202U true CN202886202U (en) | 2013-04-17 |
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| CN 201220571961 Expired - Lifetime CN202886202U (en) | 2012-10-31 | 2012-10-31 | Ultrasonic and acoustic emission test system for true triaxial test |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102954914A (en) * | 2012-10-31 | 2013-03-06 | 长江水利委员会长江科学院 | True triaxial test ultrasonic wave and acoustic emission testing system and testing method thereof |
| CN106556646A (en) * | 2016-11-18 | 2017-04-05 | 金陵科技学院 | Acoustic emission tomography determines the detecting system at damages of concrete structures position |
| CN107340229A (en) * | 2017-06-22 | 2017-11-10 | 中国矿业大学 | A kind of experimental provision and method for testing coal and rock dynamics |
| CN108225905A (en) * | 2017-12-26 | 2018-06-29 | 中国矿业大学 | A kind of true triaxial adopts the acoustic emission monitor that coal and rock power shows experiment |
| CN108956761A (en) * | 2017-05-23 | 2018-12-07 | 浙江工商职业技术学院 | Steel plate all standing ultrasonic detection device and method |
| CN109443944A (en) * | 2018-12-19 | 2019-03-08 | 北京科技大学 | The three axis flexible compression devices obtained for the real-time sound pressure information of soil-rock mixture |
| CN110618031A (en) * | 2019-09-17 | 2019-12-27 | 东北大学 | Built-in acoustic emission sensor mounting structure suitable for rock compression test |
| CN112326408A (en) * | 2020-10-09 | 2021-02-05 | 南京理工大学 | System and method for measuring wave velocity of solid medium under confining pressure state |
-
2012
- 2012-10-31 CN CN 201220571961 patent/CN202886202U/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102954914A (en) * | 2012-10-31 | 2013-03-06 | 长江水利委员会长江科学院 | True triaxial test ultrasonic wave and acoustic emission testing system and testing method thereof |
| CN106556646A (en) * | 2016-11-18 | 2017-04-05 | 金陵科技学院 | Acoustic emission tomography determines the detecting system at damages of concrete structures position |
| CN108956761A (en) * | 2017-05-23 | 2018-12-07 | 浙江工商职业技术学院 | Steel plate all standing ultrasonic detection device and method |
| CN108956761B (en) * | 2017-05-23 | 2020-12-25 | 浙江工商职业技术学院 | Steel plate full-coverage ultrasonic detection device and method |
| CN107340229A (en) * | 2017-06-22 | 2017-11-10 | 中国矿业大学 | A kind of experimental provision and method for testing coal and rock dynamics |
| CN108225905A (en) * | 2017-12-26 | 2018-06-29 | 中国矿业大学 | A kind of true triaxial adopts the acoustic emission monitor that coal and rock power shows experiment |
| CN109443944A (en) * | 2018-12-19 | 2019-03-08 | 北京科技大学 | The three axis flexible compression devices obtained for the real-time sound pressure information of soil-rock mixture |
| CN110618031A (en) * | 2019-09-17 | 2019-12-27 | 东北大学 | Built-in acoustic emission sensor mounting structure suitable for rock compression test |
| CN112326408A (en) * | 2020-10-09 | 2021-02-05 | 南京理工大学 | System and method for measuring wave velocity of solid medium under confining pressure state |
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Granted publication date: 20130417 |