CN107064301A - A kind of non-contact non-destructive testing method based on vibration measurement with laser - Google Patents
A kind of non-contact non-destructive testing method based on vibration measurement with laser Download PDFInfo
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- 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
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Abstract
The invention discloses a kind of non-contact non-destructive testing method based on vibration measurement with laser, belong to building, building, bridge, Quality of Water Conservancy Projects safety detection technology field, comprise the following steps：Determinand is determined, vibration measurement with laser device is fixed on mobile test instrument, and makes it apart from the 3m of test surfaces 0.01 of determinand；Vibration measurement with laser device is opened, makes laser vertical in test surfaces；Acted on using percussion mechanism on the measuring point that determinand is irradiated with a laser, determinand is produced vibration, while making vibration measurement with laser device with speed VHAt the uniform velocity move, and moving direction is vertical with measuring point direction of vibration；The vibration velocity V of measuring point is calculated by vibration measurement with laser deviceMove；Utilize vibration velocity V of the software to measuring pointMoveAnalyzed, obtain the inner case of determinand.This method uses non-contact testing, the error that can not only avoid sensor from contacting and produce with measured object surface, additionally it is possible to using the detection of continuous-moving type, so as to greatly improve measuring accuracy and efficiency.
Description
Technical field
The invention belongs to building, building, bridge, Quality of Water Conservancy Projects safety detection technology field, and in particular to Yi Zhongji
In the non-contact non-destructive testing method of vibration measurement with laser.
Background technology
Non-destructive testing technology is the emerging engineering science developed rapidly after World War II, and it is defined
Exactly under the premise of the original state of test substance, chemical property etc. is not destroyed, using in material because of defective or institutional framework
On difference exist and phenomenon that the physical quantity of its some physical property can be made to change, not make checked property performance
Premised on being sustained damage with form, these changes are tested, show and assessed by certain detection means, so as to understand and comment
The inspection method that property, state or internal structure of the measured objects such as valency material, product, element of installation etc. are used.
In all kinds of civil engineerings, the application of non-destructive testing technology is quite varied, the either roadbed of highway, railway
Fill, paving, or bridge, tunnel and other important feature things construction and maintenance, everywhere it can be seen that lossless inspection
The figure of survey technology.Table 1 below lists non-destructive testing technology common at present.
The field of the various lossless detection methods of table 1 and feature
Wherein, it is one of important lossless detection method using impact elasticity ripple, ultrasonic wave.However, existing impact bullet
Property the contact type measurement that uses of ripple, ultrasound examination, it is necessary to install acceleration transducer (such as Fig. 1) on testee, profit
The measurement of correlation of vibration signal is realized with the charge signal output of acceleration transducer.If measuring quality shaking compared with wisp
Dynamic, the quality of additional acceleration transducer often influences the vibration of testee, so as to produce measurement error.Meanwhile, by
In the resonance characteristics of sensing system in itself, and contact condition is bad, is likely to cause the error of test signal.It is another
Aspect, because the fixation of sensor, it is necessary to implement, therefore can not apply in follow-on test in a stationary situation, and then seriously
Ground influences testing efficiency.
The content of the invention
In order to solve the above-mentioned technical problem, the present invention discloses a kind of contactless Non-Destructive Testing side based on vibration measurement with laser
Method, this method uses non-contact testing, the error that can not only avoid sensor from contacting and produce with measured object surface, moreover it is possible to
The detection of continuous-moving type is enough used, so as to greatly improve measuring accuracy and efficiency.
The present invention is achieved through the following technical solutions：
A kind of non-contact non-destructive testing method based on vibration measurement with laser, as shown in fig. 6, comprising the following steps：
(1) determinand is determined, one section of measurement circuit is selected on the test object；
(2) vibration measurement with laser device is fixed on mobile test instrument, and makes vibration measurement with laser device apart from the survey of determinand
Examination face 0.01-3m；
(3) vibration measurement with laser device is opened, makes laser vertical in test surfaces；
(4) acted on using percussion mechanism on the measuring point that determinand is irradiated with a laser, determinand is produced vibration, make simultaneously
Vibration measurement with laser device is with speed VHAt the uniform velocity move, moving direction is vertical with measuring point direction of vibration, and moved with vibration measurement with laser device
During illuminated laser spot moved along measurement circuit；
(5) the vibration velocity V of measuring point is calculated by vibration measurement with laser deviceMove；
(6) vibration velocity V of the software to measuring point is utilizedMoveAnalyzed, obtain the thickness of determinand, defect, material and treat
Survey the evaluation of thing total quality.
Wherein, in step (5), VMoveIt is that the foundation correction of the vibration velocity V when measuring point is static is obtained, its angle correction isLaser-Doppler vibration measuring speed formula is substituted into againObtain：
In step (5), vibration measurement with laser device calculates the vibration velocity V of measuring pointMoveSpecific method it is as follows：
1) test model is built：As illustrated in fig. 2, it is assumed that point S is light source, the frequency of light is f, and the light velocity is c, and point O is
Lightwave receiver, point P is the single measuring point that speed is V, and S and O are in P both sides, and laser is sent to motion measuring point P, warp through light source S
Received after motion measuring point reflection by Lightwave receiver O, θ1And θ2Respectively SP, OP and speed V angle, when light source and light wave connect
When receiving device holding geo-stationary, it is assumed that n is along the light wave periodicity in the light path from light source to Lightwave receiver, infinitesimal
In time interval δ t, it is assumed that the distance that P is moved to P ' is V δ t.The increase number δ n of periodicity are in the light path,
Wherein, PN and PN ' is the vertical line to SP and PO works respectively, and PP ' is infinitely small, and λ and λ ' are the wavelength before and after scattering.
Above formula can be expressed as again：
Consider：
In general, it is not necessary to distinguish λ and λ ', the Doppler frequency shift of first approximation is thus obtained：
2) frequency of light wave that Lightwave receiver is received is f+ Δs fD, as shown in figure 3, for light wave along during backscattering,
When i.e. light source and Lightwave receiver part are integrated, S=O, θ1=θ2=θ, therefore have：
For the vibration velocity of single measuring point, have：
3) as shown in figure 4, on the basis of single measuring point vibration velocity V is tested out using laser-Doppler vibration measuring principle, profit
Continuous-moving type detection is carried out to determinand with vibration measurement with laser device, specifically, when vibration measurement with laser device moving direction perpendicular to
The direction of vibration of the measuring point of determinand, and its translational speed is VHWhen, test angle is：
θ is substituted into can obtain in formula -6
VMoveThe vibration velocity of obtained determinand measuring point is as tested in vibration measurement with laser device moving process.Pass through parsing again
The speed V that software is obtained to testMoveAnalyzed, you can obtain determinand inner case such as thickness, defect, material and determinand
The evaluating data of total quality.
For VMoveAnalysis method have a lot, wherein, Impact echo is one of very effective method.
As shown in figure 5, exciting impact elasticity ripple in determinand body structure surface using percussion mechanism, replaced using vibration measurement with laser
Touch sensor carry out pick-up, when vibration measurement with laser device receiving position and Position of Vibrating it is nearer when, receive ripple it is main into
It is divided into P ripples, when the P ripples excited are in inside configuration communication process, runs into the place that different interfaces or material change, P
Ripple can then launch the phenomenons such as reflection, transmission, diffraction, then the P ripples reflected are received by laser vibration measurer, when being carried out to it
Domain or the analysis of frequency domain, you can know the defect size and depth inside test structure.
In step (4), percussion mechanism is air cannon or jump bit.
In the present invention, measurement circuit is the circuit that the surfacing of determinand the preceding paragraph and laser can be irradiated to, the shifting of use
Dynamic testing tool can be the vehicles such as automobile, loading machine or homemade dolly.
The present invention compared with prior art, has the following advantages and advantages：
A kind of non-contact non-destructive testing method based on vibration measurement with laser of the present invention, measuring point position of this method to determinand
Using percussion mechanism exciting and induced vibration, the vibration for picking up measuring point part interior by non-contact laser vibration detecting device is believed
Number, it is computed and analyzes and draw the thickness or defect of determinand or the situation of material, sensor and measured object can be prevented effectively from
The error that surface contacts and produced, and using the detection of continuous-moving type, for the detection of existing single-point, test effect
Rate is greatly improved, therefore the present invention can greatly improve measuring accuracy and efficiency.
Brief description of the drawings
Accompanying drawing described herein is used for providing further understanding the embodiment of the present invention, constitutes one of the application
Point, do not constitute the restriction to the embodiment of the present invention.In the accompanying drawings：
Fig. 1 is contact Non-Destructive Testing schematic diagram in background technology；
Fig. 2 is present invention scattering Doppler frequency shift schematic diagram；
Fig. 3 is laser doppler schematic diagram of the present invention；
Fig. 4 is vibration measurement with laser follow-on test schematic diagram of the present invention；
Fig. 5 is Impact echo schematic diagram of the present invention；
Fig. 6 is engineering actual test schematic diagram of the present invention；
Fig. 7 is the anchor pole test schematic diagram of the embodiment of the present invention 1；
Fig. 8 is the Laser Measuring anchor pole oscillogram of the embodiment of the present invention 1；
Fig. 9 is the Laser Measuring anchor pole result figure of the embodiment of the present invention 1；
Figure 10 is the thickness of the liner degree schematic diagram of 2 laser follow-on test of the embodiment of the present invention two；
Figure 11 is the thickness of the liner degree result figure of 2 laser follow-on test of the embodiment of the present invention two.
Mark and corresponding parts title in accompanying drawing：
1- acceleration transducers, 2- percussion mechanisms, 3- vibration measurement with laser devices, 4- determinands, 5- anchor poles, 6- bis- is served as a contrast, at the beginning of 7-
Branch.
Embodiment
For the object, technical solutions and advantages of the present invention are more clearly understood, with reference to embodiment and accompanying drawing, to this
Invention is described in further detail, and exemplary embodiment and its explanation of the invention is only used for explaining the present invention, does not make
For limitation of the invention.
Embodiment 1
A kind of non-contact non-destructive testing method based on vibration measurement with laser of the present invention, applied to rock-bolt length noncontact without
Test is damaged, anchor pole physical length 1.3m, the concrete operations of single point laser test are as follows：
1) such as Fig. 7, vibration measurement with laser device is positioned in the range of the tested anchor pole 0.01-3m of distance；
2) laser vertical is made to be irradiated to anchor pole end face；
3) its direction of vibration is made parallel to rock-bolt length direction in anchor pole end face exciting using air cannon or jump bit；
4) gathered using the reception device of vibration measurement with laser device, preserve corresponding data；
5) by step 4) in test result import analysis software as shown in Figure 8, by analysis software in test waveform
Reflected signal recognizes that velocity of wave takes the velocity of wave 5.18Km/s of steel, calculates the rock-bolt length 1.316m being buried in the earth, error 0.016m,
As a result it is as shown in Figure 9.
Testing precision is high, and tests quick and convenient, efficiency high.
Embodiment 2
A kind of non-contact non-destructive testing method based on vibration measurement with laser of the present invention, the noncontact applied to two thickness of the liner degree connects
Continuous test, two thickness of the liner degree are designed as 0.5m, and two lining lower floors are first branch, and the concrete operations of laser follow-on test are as follows：
1) such as Figure 10, vibration measurement with laser device is positioned in the range of the tested two facings 0.01-3m of distance；
2) laser vertical is made to be irradiated to two facingss；
3) surface exciting is served as a contrast two using air cannon or jump bit, makes its direction of vibration perpendicular to device moving direction；
4) gathered using the reception device of vibration measurement with laser device, preserve corresponding data；
5) test result is imported into analysis software, the continuous signal of test is analyzed by analysis software, tested
The defective locations arrived are apart from starting point 35-40m, and as shown in figure 11, defective locations test gained thickness is significantly less than design thickness
0.5m, thus can determine whether thickness low LCL at this, there is possibility of coming to nothing.
Above-described embodiment, has been carried out further to the purpose of the present invention, technical scheme and beneficial effect
Describe in detail, should be understood that the embodiment that the foregoing is only the present invention, be not intended to limit the present invention
Protection domain, within the spirit and principles of the invention, any modification, equivalent substitution and improvements done etc. all should be included
Within protection scope of the present invention.
Claims (4)
1. a kind of non-contact non-destructive testing method based on vibration measurement with laser, it is characterised in that comprise the following steps：
(1) determinand is determined, one section of measurement circuit is selected on the test object；
(2) vibration measurement with laser device is fixed on mobile test instrument, and makes vibration measurement with laser device apart from the test surfaces of determinand
0.01-3m；
(3) vibration measurement with laser device is opened, makes laser vertical in test surfaces；
(4) acted on using percussion mechanism on the measuring point that determinand is irradiated with a laser, determinand is produced vibration, while making laser
Vibration detecting device is with speed VHAt the uniform velocity move, moving direction is vertical with measuring point direction of vibration, and with vibration measurement with laser device moving process
Middle illuminated laser spot is moved along measurement circuit；
(5) the vibration velocity V of measuring point is calculated by vibration measurement with laser deviceMove；
(6) vibration velocity V of the analysis software to measuring point is utilizedMoveAnalyzed, obtain the thickness of determinand, defect, material and treat
Survey the evaluation of thing total quality.
2. a kind of non-contact non-destructive testing method based on vibration measurement with laser according to claim 1, it is characterised in that step
Suddenly in (5), VMoveIt is that the foundation correction of the vibration velocity V when measuring point is static is obtained, its angle correction isGeneration again
Enter laser-Doppler vibration measuring speed formulaObtain：
3. a kind of non-contact non-destructive testing method based on vibration measurement with laser according to claim 1, it is characterised in that step
Suddenly in (5), vibration measurement with laser device calculates the vibration velocity V of measuring pointMoveSpecific method it is as follows：
1) test model is built：Postulated point S is light source, and the frequency of light is f, and the light velocity is c, and point O is Lightwave receiver, point P
The single measuring point for being V for speed, S and O are in P both sides, and laser is sent to motion measuring point P through light source S, after moving measuring point reflection
Received by Lightwave receiver O, θ1And θ2Respectively SP, OP and speed V angle, when light source and Lightwave receiver keep relatively quiet
When only, it is assumed that n is light wave periodicity of the edge in the light path from light source to Lightwave receiver, in infinitesimal time interval δ t,
It is assumed that the distance that P is moved to P ' is V δ t.The increase number δ n of periodicity are in the light path,
Wherein, PN and PN ' is the vertical line to SP and PO works respectively, and PP ' is infinitely small, and λ and λ ' are the wavelength before and after scattering.Above formula
It can be expressed as again：
Consider：
In general, it is not necessary to distinguish λ and λ ', the Doppler frequency shift of first approximation is thus obtained：
2) frequency of light wave that Lightwave receiver is received is f+ Δs fD, for light wave along during backscattering, i.e., light source and light wave are received
When device is integrated, S=O, θ1=θ2=θ, therefore have：
For the vibration velocity of single measuring point, have：
3) on the basis of single measuring point vibration velocity V is tested out using laser-Doppler vibration measuring principle, vibration measurement with laser device is utilized
Continuous-moving type detection is carried out to determinand, specifically, when vibration measurement with laser device moving direction is perpendicular to the measuring point of determinand
Direction of vibration, and its translational speed is VHWhen, test angle is：
θ is substituted into can obtain in formula -6
VMoveAs vibration measurement with laser device tests the vibration velocity of obtained determinand measuring point along along measurement circuit moving process.
4. a kind of non-contact non-destructive testing method based on vibration measurement with laser according to claim 1, it is characterised in that step
Suddenly in (4), percussion mechanism is air cannon or jump bit.
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Cited By (8)
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| CN107764897A (en) * | 2017-10-17 | 2018-03-06 | 四川升拓检测技术股份有限公司 | Contactless continuous-moving type lossless detection method based on air acceleration |
| CN107782786A (en) * | 2017-09-27 | 2018-03-09 | 重庆交通大学 | A kind of steel construction rust detection device and method based on pulse microwave pyrogenicity vibration measuring |
| CN109163869A (en) * | 2018-08-15 | 2019-01-08 | 中国十七冶集团有限公司 | A kind of Antiseismic building characteristic test system and test method |
| CN110658057A (en) * | 2019-11-13 | 2020-01-07 | 合肥工业大学 | Method and device for measuring section deformation of circular pipe in drop hammer impact test |
| CN112393797A (en) * | 2020-11-26 | 2021-02-23 | 国网山西省电力公司电力科学研究院 | Reactor vibration speed detection method and device, control equipment and storage medium |
| CN113639846A (en) * | 2021-07-29 | 2021-11-12 | 江苏建科鉴定咨询有限公司 | Laser vibration test inspection method for detecting pasting quality of thin-plastering heat-preservation and heat-insulation system |
| CN113654647A (en) * | 2021-06-29 | 2021-11-16 | 国网江苏省电力有限公司电力科学研究院 | Non-contact GIL vibration detection method and device |
| CN114295731A (en) * | 2021-12-28 | 2022-04-08 | 杭州电子科技大学 | Method for measuring depth of subsurface defect based on laser excitation longitudinal wave |
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Cited By (10)
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| CN107782786A (en) * | 2017-09-27 | 2018-03-09 | 重庆交通大学 | A kind of steel construction rust detection device and method based on pulse microwave pyrogenicity vibration measuring |
| CN107782786B (en) * | 2017-09-27 | 2024-05-28 | 重庆交通大学 | Steel structure corrosion detection device and method based on pulse microwave heating vibration measurement |
| CN107764897A (en) * | 2017-10-17 | 2018-03-06 | 四川升拓检测技术股份有限公司 | Contactless continuous-moving type lossless detection method based on air acceleration |
| CN109163869A (en) * | 2018-08-15 | 2019-01-08 | 中国十七冶集团有限公司 | A kind of Antiseismic building characteristic test system and test method |
| CN110658057A (en) * | 2019-11-13 | 2020-01-07 | 合肥工业大学 | Method and device for measuring section deformation of circular pipe in drop hammer impact test |
| CN112393797A (en) * | 2020-11-26 | 2021-02-23 | 国网山西省电力公司电力科学研究院 | Reactor vibration speed detection method and device, control equipment and storage medium |
| CN113654647A (en) * | 2021-06-29 | 2021-11-16 | 国网江苏省电力有限公司电力科学研究院 | Non-contact GIL vibration detection method and device |
| CN113639846A (en) * | 2021-07-29 | 2021-11-12 | 江苏建科鉴定咨询有限公司 | Laser vibration test inspection method for detecting pasting quality of thin-plastering heat-preservation and heat-insulation system |
| CN114295731A (en) * | 2021-12-28 | 2022-04-08 | 杭州电子科技大学 | Method for measuring depth of subsurface defect based on laser excitation longitudinal wave |
| CN114295731B (en) * | 2021-12-28 | 2023-02-21 | 杭州电子科技大学 | Method for measuring subsurface defect depth based on laser excitation longitudinal wave |
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