【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、コンクリート構造物の品質管理および劣化
試験、あるいは材木、強化プラスチックFRP等の非破壊
検査に使用される超音波測定に係り、特に、横波の音速
を正確に測定できるようにした超音波試験における横波
音速測定方法および装置に関するものである。The present invention relates to an ultrasonic measurement used for quality control and deterioration tests of concrete structures or nondestructive inspection of timber, reinforced plastic FRP, etc., and in particular, The present invention relates to a method and an apparatus for measuring a sound speed of a shear wave in an ultrasonic test, which can accurately measure the sound speed of a shear wave.
［従来の技術］ 建築、土木の分野において、コンクリートの圧縮強度
の測定、均一性の判定および内部欠陥の検出は通常超音
波試験により行われており、その構成は第５図に示すよ
うである。第５図a,bにおいて、１は超音波パルスの発
振を行う送信用探触子、２は透過波、反射波を検出する
受信用探触子、３は試験の対象となっているコンクリー
トを示す。第５図ａはコンクリートの圧縮強度を求める
ための構成であり、この場合、送信用探触子１はコンク
リート３の一面、例えば表面に、受信用探触子２はコン
クリート３の他面、例えば裏面にそれぞれ配置される。
送信用探触子１から発信された超音波パルスはコンクリ
ート３をそのまま透過したり、コンクリート３の中で反
射したりするが、透過波は受信用探触子２で検出され、
図示しないオシロスコープ上に受信波形として表示され
る。オペレータは当該受信波形から読み取った超音波パ
ルスの音速と、予め作成されているキャリブレーション
カーブとから圧縮強度を求めることができる。また、第
５図ｂに示すように、送信用探触子１および受信用探触
子２を共にコンクリート３の表面に配置した場合には、
受信用探触子２で検出した反射波をオシロスコープ上に
表示し、当該反射波形から読み取った伝播時間と、予め
知られている音速とから反射源の位置、即ち内部欠陥の
位置を推定することができる。[Prior Art] In the fields of construction and civil engineering, measurement of compressive strength of concrete, determination of uniformity and detection of internal defects are usually performed by ultrasonic testing, and the configuration is as shown in FIG. . 5a and 5b, 1 is a transmitting probe for oscillating an ultrasonic pulse, 2 is a receiving probe for detecting a transmitted wave and a reflected wave, and 3 is a concrete object to be tested. Show. FIG. 5a shows a configuration for determining the compressive strength of concrete. In this case, the transmitting probe 1 is on one surface, for example, the surface of the concrete 3, and the receiving probe 2 is on the other surface, for example, of the concrete 3. Each is arranged on the back surface.
The ultrasonic pulse transmitted from the transmitting probe 1 passes through the concrete 3 as it is or reflects in the concrete 3, but the transmitted wave is detected by the receiving probe 2,
The received waveform is displayed on an oscilloscope (not shown). The operator can obtain the compression strength from the sound speed of the ultrasonic pulse read from the received waveform and a calibration curve created in advance. Further, as shown in FIG. 5b, when both the transmitting probe 1 and the receiving probe 2 are arranged on the surface of the concrete 3,
Displaying the reflected wave detected by the receiving probe 2 on an oscilloscope, and estimating the position of the reflection source, that is, the position of the internal defect from the propagation time read from the reflected waveform and the sound velocity known in advance. Can be.
［発明が解決しようとする課題］ しかしながら、従来のものにおいては、次のような問
題が生じていた。つまり、超音波試験に使用される超音
波には縦波と横波があり、特に、圧縮強度の重要なファ
クターである弾性係数等を求める場合には横波の音速の
情報が不可欠である。従って、圧縮強度を求める場合に
は横波探触子を用いるのであるが、第６図に示すよう
に、横波探触子５は振動子の径方向のすべり振動成分と
共に、振動子の厚み方向の振動成分が発生するので、す
べり変形により横波成分が、厚み変形により縦波成分が
同時に発生することになる。このためオシロスコープ上
に表示される受信波形は例えば第７図に示すように横波
反射波成分６と縦波反射波成分７が干渉した波形とな
り、横波だけの伝播時間を読み取ることが困難となって
いる。なお、第７図において横軸は時間を示す。従っ
て、音速を高精度に判定することが難しいばかりか、横
波だけの波形解析を行うにも障害となっているものであ
る。[Problem to be Solved by the Invention] However, the following problem has occurred in the conventional device. That is, there are longitudinal waves and transverse waves in the ultrasonic waves used for the ultrasonic test. In particular, when determining an elastic coefficient or the like which is an important factor of the compressive strength, information on the sound speed of the transverse waves is indispensable. Therefore, in order to determine the compressive strength, a shear wave probe is used. As shown in FIG. 6, the shear wave probe 5 includes the shear vibration component in the radial direction of the oscillator and the shear wave component in the thickness direction of the oscillator. Since a vibration component is generated, a shear wave component and a longitudinal wave component are simultaneously generated by slip deformation and thickness deformation. For this reason, the received waveform displayed on the oscilloscope becomes a waveform in which the transverse reflected wave component 6 and the longitudinal reflected wave component 7 interfere as shown in FIG. 7, for example, and it becomes difficult to read the propagation time of only the transverse wave. I have. In FIG. 7, the horizontal axis represents time. Therefore, it is not only difficult to determine the sound speed with high accuracy, but also an obstacle to performing a waveform analysis of only the transverse wave.
本発明は、上記の課題を解決するものであって、横波
の伝播時間を高精度で測定することができる超音波試験
における横波音速測定方法および装置を提供することを
目的とするものである。An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a method and an apparatus for measuring the acoustic velocity of a shear wave in an ultrasonic test capable of measuring the propagation time of a shear wave with high accuracy.
［課題を解決するための手段］ 上記の目的を達成するために、本発明の超音波試験に
おける横波音速測定方法は、受信用探触子の出力を周波
数領域に変換し、該変換出力の中の所望の周波数成分を
抽出し、該抽出した信号を再び時系列信号に変換して波
形表示することを特徴とし、また、本発明の超音波試験
における横波音速測定装置は、受信用探触子と、前記受
信用探触子の出力を周波数領域に変換する第１の信号変
換手段と、前記信号変換手段の出力の中、所望の周波数
成分を抽出する信号処理手段と、前記信号処理手段の出
力を時系列信号に変換する第２の信号変換手段と、前記
第２の信号変換手段の出力を波形表示する表示手段とを
具備することを特徴とする。Means for Solving the Problems In order to achieve the above object, a method for measuring a shear wave velocity in an ultrasonic test according to the present invention converts the output of a receiving probe into a frequency domain, and Extracting a desired frequency component, converting the extracted signal into a time-series signal again and displaying a waveform, and a shear wave velocity measuring apparatus in an ultrasonic test according to the present invention is characterized in that a receiving probe A first signal converting means for converting an output of the receiving probe into a frequency domain; a signal processing means for extracting a desired frequency component from an output of the signal converting means; A second signal conversion means for converting an output into a time-series signal, and a display means for displaying a waveform of the output of the second signal conversion means are provided.
［作用］ 本発明においては、受信用探触子で得られた字形列信
号を周波数領域に変換することにより縦波成分と横波成
分とを明確に分離できるので、容易に横波成分のみを抽
出することができ、以て横波の音速、伝播時間を正確に
知ることができるものである。[Operation] In the present invention, since the longitudinal wave component and the transverse wave component can be clearly separated by converting the character string signal obtained by the receiving probe into the frequency domain, only the transverse wave component can be easily extracted. Thus, the sound speed and propagation time of the shear wave can be accurately known.
［実施例］ 上述したように、横波探触子はどうしても縦波成分を
も生じてしまうので、本発明では探触子はそのままにし
て受信用探触子の出力を信号処理することにより縦波成
分と横波成分とを分離しようとするものである。つま
り、縦波と横波とでは周波数成分が異なるので、受信用
探触子の出力である時系列の信号を周波数領域に変換
し、横波成分、または縦波成分のみを得ようとするもの
である。[Example] As described above, since the shear wave probe inevitably generates a longitudinal wave component, in the present invention, the longitudinal wave component is obtained by performing signal processing on the output of the receiving probe without changing the probe. The component and the shear wave component are to be separated. In other words, since the longitudinal wave and the transverse wave have different frequency components, the time-series signal output from the receiving probe is converted into the frequency domain to obtain only the transverse wave component or the longitudinal wave component. .
以下、図面を参照しつつ実施例を説明する。 Hereinafter, embodiments will be described with reference to the drawings.
第１図は本発明に係る超音波試験における横波音速測
定方法の１実施例の構成を示す図であり、図中、11は受
信用探触子、12はFFT（高速フーリエ変換器）等のフー
リエ変換手段、13は信号処理手段、14はIFFT（逆高速フ
ーリエ変換器）等の逆フーリエ変換手段、15はオシロス
コープ等の表示手段を示す。FIG. 1 is a diagram showing a configuration of one embodiment of a method for measuring a shear wave velocity in an ultrasonic test according to the present invention, in which 11 is a receiving probe, and 12 is an FFT (fast Fourier transformer) or the like. Fourier transform means, 13 denotes signal processing means, 14 denotes an inverse Fourier transform means such as an IFFT (inverse fast Fourier transformer), and 15 denotes a display means such as an oscilloscope.
第１図の構成において、受信用探触子11で検出される
信号中には、縦波成分と横波成分が含まれていることは
上述したところから明かである。従って、受信用探触子
11で検出した信号をそのままオシロスコープに表示する
と例えば第７図に示すように横波成分６と縦波成分７と
が干渉した波形となる。そこで、本発明においては、時
系列で得られる受信用探触子１の出力をフーリエ変換手
段12によりフーリエ変換して周波数領域に変換する。第
７図に示す時系列の信号をフーリエ変換手段12により周
波数領域に変換すると、その出力は第２図に示すよう
に、低周波側に横波成分16が得られ、高周波側に縦波成
分７が得られる。従って、低域濾波器等の適当なフィル
タからなる信号処理手段13により第３図に示すように、
低周波側の横波成分16のみを取り出し、更に、逆フーリ
エ変換手段１で周波数領域の信号を時系列の信号に戻し
て表示手段15に入力すれば、第４図に示すように横波成
分６のみの信号波形を得ることができる。なお、第２図
および第３図の横軸は周波数である。It is apparent from the above description that the signal detected by the receiving probe 11 in the configuration of FIG. 1 includes a longitudinal wave component and a transverse wave component. Therefore, the receiving probe
When the signal detected at 11 is displayed on an oscilloscope as it is, for example, as shown in FIG. 7, a waveform is obtained in which the transverse wave component 6 and the longitudinal wave component 7 interfere. Therefore, in the present invention, the output of the receiving probe 1 obtained in a time series is Fourier-transformed by the Fourier transform means 12 and is transformed into the frequency domain. When the time-series signal shown in FIG. 7 is transformed into the frequency domain by the Fourier transform means 12, the output is a transverse wave component 16 on the low frequency side and a longitudinal wave component 7 on the high frequency side as shown in FIG. Is obtained. Therefore, as shown in FIG. 3, the signal processing means 13 comprising an appropriate filter such as a low-pass filter
If only the transverse wave component 16 on the low frequency side is taken out, and the signal in the frequency domain is converted back to a time-series signal by the inverse Fourier transform means 1 and input to the display means 15, only the transverse wave component 6 as shown in FIG. Can be obtained. The horizontal axis in FIGS. 2 and 3 is the frequency.
以上、本発明の１実施例を説明したが、本発明は上記
の実施例に限定されるものではなく、種々の変形が可能
である。例えば、時系列信号を周波数領域に変換する手
段、およびその逆変換手段はフーリエ変換に限らず同様
の機能を有し、高速に動作するものであれば使用するこ
とができる。また、上記実施例では横波成分を抽出する
例を説明したが、縦波を抽出んする必要があるのであれ
ば信号処理手段13として高域濾波器を使用すればよいも
のである。更に、上記実施例ではコンクリートの試験を
例にとったが、材木、FRP等の非破壊検査にも適用でき
るものであることは明かであろう。As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, A various deformation | transformation is possible. For example, the means for converting a time-series signal into the frequency domain and the inverse transform means are not limited to the Fourier transform, and may be used as long as they have the same function and operate at high speed. Further, in the above-described embodiment, an example in which a transverse wave component is extracted has been described. However, if it is necessary to extract a longitudinal wave, a high-pass filter may be used as the signal processing means 13. Further, in the above embodiment, a concrete test was taken as an example, but it is apparent that the present invention can be applied to nondestructive inspection of timber, FRP, and the like.
［発明の効果］ 以上の説明から明らかなように、本発明によれば、超
音波試験において、受信用探触子で検出された信号を縦
波成分と横波成分とに分離できるので横波の伝播時間を
高い精度で読み取ることができるものである。[Effects of the Invention] As is clear from the above description, according to the present invention, in an ultrasonic test, a signal detected by a receiving probe can be separated into a longitudinal wave component and a transverse wave component, so that propagation of a transverse wave can be achieved. Time can be read with high accuracy.
第１図は本発明に係る超音波試験における横波音速測定
方法および装置の１実施例の構成を示す図、第２図は受
信用探触子の出力をフーリエ変換して得られる信号を示
す図、第３図は信号処理手段の出力を示す図、第４図は
逆フーリエ変換手段の出力を示す図、第５図は超音波試
験の一般的な構成を示す図、第６図は横波探触子の振動
を説明する図、第７図は従来の測定で得られる信号波形
の例を示す図である。 11……受信用探触子、12……フーリエ変換手段、13……
信号処理手段、14……逆フーリエ変換手段、15……オシ
ロスコープ。FIG. 1 is a diagram showing a configuration of an embodiment of a method and an apparatus for measuring a shear wave velocity in an ultrasonic test according to the present invention, and FIG. 2 is a diagram showing a signal obtained by Fourier transforming an output of a receiving probe. 3 is a view showing the output of the signal processing means, FIG. 4 is a view showing the output of the inverse Fourier transform means, FIG. 5 is a view showing a general configuration of the ultrasonic test, and FIG. FIG. 7 is a view for explaining the vibration of a touch element, and FIG. 7 is a view showing an example of a signal waveform obtained by a conventional measurement. 11 ... receiving probe, 12 ... Fourier transform means, 13 ...
Signal processing means, 14 ... Inverse Fourier transform means, 15 ... Oscilloscope.
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1147475AJP2740871B2 (en) | 1989-06-09 | 1989-06-09 | Method and apparatus for measuring shear wave velocity in ultrasonic test |
| GB9004008AGB2232487B (en) | 1989-06-09 | 1990-02-22 | Ultrasonic measuring apparatus including a high-damping probe |
| US07/483,843US5078013A (en) | 1989-06-09 | 1990-02-23 | Ultrasonic measuring apparatus using a high-damping probe |
| DE4006454ADE4006454A1 (en) | 1989-06-09 | 1990-03-01 | STRONG DAMPING MEASURING PART AND ULTRASONIC MEASURING DEVICE |
| KR1019900003647AKR910001359A (en) | 1989-06-09 | 1990-03-19 | High damping transducer and ultrasonic measuring device using it |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1147475AJP2740871B2 (en) | 1989-06-09 | 1989-06-09 | Method and apparatus for measuring shear wave velocity in ultrasonic test |
| Publication Number | Publication Date |
|---|---|
| JPH0312552A JPH0312552A (en) | 1991-01-21 |
| JP2740871B2true JP2740871B2 (en) | 1998-04-15 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1147475AExpired - Fee RelatedJP2740871B2 (en) | 1989-06-09 | 1989-06-09 | Method and apparatus for measuring shear wave velocity in ultrasonic test |
| Country | Link |
|---|---|
| JP (1) | JP2740871B2 (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2682552B2 (en)* | 1991-10-23 | 1997-11-26 | 鹿島建設株式会社 | Concrete wall defect detection method |
| JP4796092B2 (en)* | 2008-05-21 | 2011-10-19 | アイリスオーヤマ株式会社 | chest |
| Publication number | Publication date |
|---|---|
| JPH0312552A (en) | 1991-01-21 |
| Publication | Publication Date | Title |
|---|---|---|
| Alleyne et al. | A two-dimensional Fourier transform method for the measurement of propagating multimode signals | |
| Jeong et al. | Fracture source location in thin plates using the wavelet transform of dispersive waves | |
| Krause et al. | Elastic wave modes for the assessment of structural timber: ultrasonic echo for building elements and guided waves for pole and pile structures | |
| US5078013A (en) | Ultrasonic measuring apparatus using a high-damping probe | |
| Goujon et al. | Behaviour of acoustic emission sensors using broadband calibration techniques | |
| Smagin et al. | Fast time-domain laser Doppler vibrometry characterization of surface acoustic waves devices | |
| KR101251204B1 (en) | Ultrasonic nondestructive inspection device and ultrasonic nondestructive inspection method | |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |