2003 Fiscal Year Final Research Report Summary
Development of flaw evaluation system for large civil structures by using low frequency ultrasonic wave and scattered waveforms
Project/Area Number |
13555124
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 展開研究 |
Research Field |
構造工学・地震工学
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Research Institution | Tohoku University |
Principal Investigator |
YAMADA Masaki Tohoku University, Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (30323083)
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Co-Investigator(Kenkyū-buntansha) |
KIMURA Tomonori Mitsubishi Electric Co., Optical and Ultrasonic Technology, Team Researcher, 情報技術総合研究所・光超音波チーム, 主事(研究職)
TERADA Kenjiro Tohoku University, Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (40282678)
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Project Period (FY) |
2001 – 2003
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Keywords | NDE / civil structures / ultrasonic wave / low frequency / imaging / scattering amplitude / concrete / linearized inverse scattering method |
Research Abstract |
The research about the technique of ultrasonic flaw reconstruction in elastic materials based on inverse scattering methods are carried out to develop a non-destructive evaluation system for large civil structures made by concrete materials. In this project, two and three dimensional elastodynamic inverse scattering methods are developed. The scattered wave measurement and the attenuation and phase velocity measurement were carried out for utilization of measured wave data. And, the comparison of reconstructed shapes by Born and Kirchhoff inverse scattering methods brought flaw characterization system. The shape reconstruction of flaws in the concrete materials by Born and Kirchhoff inverse scattering method is investigated. In this method, the angular and frequency diversities of the scattered waves are superposed in the form of the Fourier transform in the polar coordinate. An efficient method to accelerate the inversion process is proposed by rearranging the scattered wave data from the polar coordinate to the rectangular coordinate. The concrete specimens, that contain flaw models and has flat surface, are prepared and the scattered waveforms are acquired from the pulse-echo measurement. The performance of the shape reconstructions is shown for flaw models is the prepared specimens. As the result, the possibility of this method to reconstruct the shape of flow in concrete materials is shown.
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Research Products
(12 results)